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https://en.wikipedia.org/wiki/Photon-induced%20electric%20field%20poling
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In physics, photon-induced electric field poling is a phenomenon whereby a pattern of local electric field orientations can be encoded in a suitable ferroelectric material, such as perovskite. The resulting encoded material is conceptually similar to the pattern of magnetic field orientations within the magnetic domains of a ferromagnet, and thus may be considered as a possible technology for computer storage media. The encoded regions are optically active (have a varying index of refraction) and thus may be "read out" optically.
Encoding process
The encoding process proceeds by application of ultraviolet light tuned to the absorption band associated with the transition of electrons from the valence band to the conduction band. During UV application, an external electric field is used to modify the electric dipole moment of regions of the ferroelectric material that are exposed to UV light. By this process, a pattern of local electric field orientations can be encoded.
Technically, the encoding effect proceeds by the creation of a population inversion between the valence and conduction bands, with the resulting creation of plasmons. During this time, ferroelectric perovskite materials can be forced to change geometry by the application of an electric field. The encoded regions become optically active due to the Pockels effect.
Decoding process
The pattern of ferroelectric domain orientations can be read out optically. The refractive index of the ferroelectric material at wavelengths from near-infrared through to near-ultraviolet is affected by the electric field within the material. A changing pattern of electric field domains within a ferroelectric substrate results in different regions of the substrate having different refractive indices. Under these conditions, the substrate behaves as a diffraction grating, allowing the pattern of domains to be inferred from the interference pattern present in the transmitted readout beam.
See also
Electro-optic effect
Bir
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https://en.wikipedia.org/wiki/Linear%20connection
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In the mathematical field of differential geometry, the term linear connection can refer to either of the following overlapping concepts:
a connection on a vector bundle, often viewed as a differential operator (a Koszul connection or covariant derivative);
a principal connection on the frame bundle of a manifold or the induced connection on any associated bundle — such a connection is equivalently given by a Cartan connection for the affine group of affine space, and is often called an affine connection.
The two meanings overlap, for example, in the notion of a linear connection on the tangent bundle of a manifold.
In older literature, the term linear connection is occasionally used for an Ehresmann connection or Cartan connection on an arbitrary fiber bundle, to emphasise that these connections are "linear in the horizontal direction" (i.e., the horizontal bundle is a vector subbundle of the tangent bundle of the fiber bundle), even if they are not "linear in the vertical (fiber) direction". However, connections which are not linear in this sense have received little attention outside the study of spray structures and Finsler geometry.
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https://en.wikipedia.org/wiki/Passive%20electronically%20scanned%20array
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A passive electronically scanned array (PESA), also known as passive phased array, is an antenna in which the beam of radio waves can be electronically steered to point in different directions (that is, a phased array antenna), in which all the antenna elements are connected to a single transmitter (such as a magnetron, a klystron or a travelling wave tube) and/or receiver.
The largest use of phased arrays is in radars. Most phased array radars in the world are PESA. The civilian microwave landing system uses PESA transmit-only arrays.
A PESA contrasts with an active electronically scanned array (AESA) antenna, which has a separate transmitter and/or receiver unit for each antenna element, all controlled by a computer; AESA is a more advanced, sophisticated versatile second-generation version of the original PESA phased array technology. Hybrids of the two can also be found, consisting of subarrays that individually resemble PESAs, where each subarray has its own RF front end. Using a hybrid approach, the benefits of AESAs (e.g., multiple independent beams) can be realized at a lower cost compared to true AESAs.
Pulsed radar systems work by connecting an antenna to a powerful radio transmitter to emit a short pulse of signal. The transmitter is then disconnected and the antenna is connected to a sensitive receiver which amplifies any echos from target objects. By measuring the time it takes for the signal to return, the radar receiver can determine the distance to the object. The receiver then sends the resulting output to a display of some sort. The transmitter elements were typically klystron tubes or magnetrons, which are suitable for amplifying or generating a narrow range of frequencies to high power levels. To scan a portion of the sky, a non-PESA radar antenna must be physically moved to point in different directions. In contrast, the beam of a PESA radar can rapidly be changed to point in a different direction, simply by electrically adjusting the phase
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https://en.wikipedia.org/wiki/Gerald%20Wingrove
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Gerald Amery Wingrove (1934 - 2019) was a model engineer and author from the United Kingdom. He is best known as a modeller of cars.
Career
Wingrove left his job as a lathe operator to create models full-time in November 1967, and launched himself as a freelance model engineer, since which time he has hand crafted in metal almost 280 automobile miniatures in the scales of 1/20 & 1/15th, primarily in 1/15th scale. Most of these were commissioned by the vehicles' owners.
The first sale of his work by a major London Auction House was by Christie's on 2 August 1967 with the sale of 2 models of sailing ships in 96th scale and a SE5A aircraft model (1/20th scale) in brass and silk.
Further sales of his work were with Brooks (later amalgamated with Bonhams) of London, 21 Lots, in (Sale 112) on 4 December 1999 – and Bonhams (Sale 1793) with 74 Lots on 1 December 2003, in London.
In July 2000, Wingrove was made a Member of the Order of the British Empire for craftsmanship, and "services to Model Engineering"
In March 2005 Wingrove was awarded ‘Metalworking Craftsman of the Year’, by The Joe Martin Foundation for Exceptional Craftsmanship in the USA.
As well as cars, Wingrove has also created ship models and dioramas, the largest being the 25 square feet model of the village and ship yard of Bucklers Hard, commissioned for the Bucklers Hard Maritime Museum.
Publications
The Techniques of Ship Modeling (1974)
The Complete Car Modeller (1978)
The Model Cars of Gerald Wingrove (1979)
Unimat Lathe Projects: A Beginners Guide to the Lathe and How to Make Ten Useful Tools (1979)
The Complete Car Modeller 1 (1993)
Anatomy of a Bugatti Royale (1993)
Art of the Automobile in Miniature(2004)
The Complete Car Modeller 2 (2005)
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https://en.wikipedia.org/wiki/National%20Numeracy%20Strategy
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The National Numeracy Strategy arose out of the National Numeracy Project in 1996, led by a Numeracy Task Force in England. The strategy included an outline of expected teaching in mathematics for all pupils from Reception to Year 6.
In 2003, the strategy, including the framework for teaching, was absorbed into the broader Primary National Strategy. The framework for teaching was updated in 2006.
See also
National Curriculum (England, Wales and Northern Ireland)
Key Stage
Chunking (division)
Grid method multiplication
Number bond
Further reading
Department for Education and Employment (1998), The implementation of the National Numeracy Strategy: The final report of the Numeracy Task Force, London: DfEE
Department for Education and Employment (1999), The National Numeracy Strategy: framework for teaching mathematics from reception to Year 6, London: DfEE.
QCA (1999), Standards in mathematics: exemplification of key learning objectives from reception to year 6
Rob Eastaway, Why parents can't do maths today, BBC News, 10 September 2010
Ian Thompson (2000), Is the National Numeracy Strategy evidence based?, Mathematics Teaching, 171, 23–27
Dylan V. Jones (2002), National numeracy initiatives in England and Wales: a comparative study of policy, The Curriculum Journal, 13 (1), 5–23.
Chris Kyriacou and Maria Goulding (2004), A systematic review of the impact of the Daily Mathematics Lesson in enhancing pupil confidence and competence in early mathematics, Evidence for Policy and Practice Information and Co-ordinating Centre (EPPI), Institute of Education, London.
External links
Government Primary Frameworks website (Archived, via the National Archives)
Education in England
Mathematics education in the United Kingdom
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https://en.wikipedia.org/wiki/French%20ship%20Pourquoi%20Pas%3F%20%282005%29
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Pourquoi Pas ? () is a research vessel built in Saint-Nazaire, France by Alstom Marine for IFREMER and the French Navy. She is currently primarily used by SHOM (Service hydrographique et océanographique de la Marine). She was ordered in December 2002 and completed in July 2005. The 66 million euro cost was financed by IFREMER (55%) and the French Navy (45%). She is named after explorer Jean-Baptiste Charcot's famous ship. A space is required immediately before a question mark in French orthography, and accordingly, in French Pourquoi Pas ? is the correct way to write the name.
Pourquoi Pas ? is used 150 days per year by the French Navy and 180 days per year by IFREMER. She was designed for hydrography, geoscience, and physical, chemical, and biological oceanography, as well as to launch small submarines such as the crewed submersible Nautile and the ROV .
Notably, Pourquoi Pas ? has been used for the 2007 deployment and connection operations for the ANTARES neutrino telescope.
In 2008, Pourquoi Pas ? was used for the initial testing and operations of the PERISCOP, a pressurized deep sea fish recovery device.
In June 2009 she assisted in the recovery of Air France Flight 447.
External links
Pourquoi-Pas ? site at IFREMER
Netmarine
BBC article about the PERISCOP
This article was translated from the original article from the French Wikipedia, in 2006.
IFREMER
Research vessels of France
Pourquoi Pas?
2004 ships
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https://en.wikipedia.org/wiki/Luteinizing%20hormone/choriogonadotropin%20receptor
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The luteinizing hormone/choriogonadotropin receptor (LHCGR), also lutropin/choriogonadotropin receptor (LCGR) or luteinizing hormone receptor (LHR) is a transmembrane receptor found predominantly in the ovary and testis, but also many extragonadal organs such as the uterus and breasts. The receptor interacts with both luteinizing hormone (LH) and chorionic gonadotropins (such as hCG in humans) and represents a G protein-coupled receptor (GPCR). Its activation is necessary for the hormonal functioning during reproduction.
LHCGR gene
The gene for the LHCGR is found on chromosome 2 p21 in humans, close to the FSH receptor gene. It consists of 70 kbp (versus 54 kpb for the FSHR). The gene is similar to the gene for the FSH receptor and the TSH receptor.
Receptor structure
The LHCGR consists of 674 amino acids and has a molecular mass of about 85–95 kDA based on the extent of glycosylation.
Like other GPCRs, the LHCG receptor possess seven membrane-spanning domains or transmembrane helices. The extracellular domain of the receptor is heavily glycosylated. These transmembrane domains contain two highly conserved cysteine residues, which build disulfide bonds to stabilize the receptor structure. The transmembrane part is highly homologous with other members of the rhodopsin family of GPCRs. The C-terminal domain is intracellular and brief, rich in serine and threonine residues for possible phosphorylation.
Ligand binding and signal transduction
Upon binding of LH to the external part of the membrane spanning receptor, a transduction of the signal takes place. This process results in the activation of a heterotrimeric G protein. Binding of LH to the receptor shifts its conformation. The activated receptor promotes the binding of GTP to the G protein and its subsequent activation. After binding GTP, the G protein heterotrimer detaches from the receptor and disassembles. The alpha-subunit Gs binds adenylate cyclase and activates the cAMP system.
It is believed tha
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https://en.wikipedia.org/wiki/Cue%20reactivity
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Cue reactivity is a type of learned response which is observed in individuals with an addiction and involves significant physiological and subjective reactions to presentations of drug-related stimuli (i.e., drug cues).
In investigations of these reactions in people with substance use disorders, changes in self-reported drug craving, physiological responses, and drug use are monitored as they are exposed to drug-related cues (e.g., cigarettes, bottles of alcohol, drug paraphernalia) or drug-neutral cues (e.g., pencils, glasses of water, a set of car keys).
Scientific theory
Cue reactivity is considered a risk factor for recovering addicts to relapse. There are two general types of cues: discrete which includes the substance itself and contextual which includes environments in which the substance is found. For example, for an alcoholic an alcoholic beverage would be a discrete cue and a bar would be a contextual cue. There are many different reactions to cues including withdrawal-like responses, opponent process responses, and substance-like responses.
A meta-analysis of 41 cue reactivity studies with people that have an alcohol, heroin, or cocaine addiction strongly supports the finding that people who have addictions have significant cue-specific reactions to drug-related stimuli. In general, these individuals, regardless of drug of abuse, report robust increases in craving and exhibit modest changes in autonomic responses, such as increases in heart rate and skin conductance and decreases in skin temperature, when exposed to drug-related versus neutral stimuli. Surprisingly, despite their obvious clinical relevance, drug use or drug-seeking behaviors are seldom measured in cue reactivity studies. However, when drug-use measures are used in cue reactivity studies the typical finding is a modest increase in drug-seeking or drug-use behavior.
Development
Clinical implications
Since people with substance use disorders are highly reactive to environmental cues pre
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https://en.wikipedia.org/wiki/Ryukyu%20kingfisher
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The Ryukyu kingfisher (Todiramphus cinnamominus miyakoensis) is an enigmatic taxon of tree kingfisher. It is extinct and is only known from a single specimen. Its taxonomic status is doubtful; it is most likely a subspecies of the Guam kingfisher, which would make its scientific name Todiramphus cinnamominus miyakoensis. As the specimen is at the Yamashina Institute for Ornithology, the question could be resolved using DNA sequence analysis; at any rate, the Guam kingfisher is almost certainly the closest relative of the Ryukyu bird. The IUCN considers this bird a subspecies and has hence struck it from its redlist.
The one known bird, probably a male, was according to its label collected on Miyako-jima, the main island of the Miyako group, Ryūkyū Shotō, on February 5, 1887. While it is often and correctly stated that specimen labels may be incorrect or misleading, the locality, to the northwest of the extant populations of Todiramphus cinnamominus, seems sound in a biogeographical sense. At least the specimen labels of Ryukyu collections by later Japanese collectors are usually very reliable; whether this is true for earlier collection too is not known.
The only differences between the Miyako-jima bird and males of the Guam kingfisher (the nominate subspecies of the Micronesian kingfisher; presently only surviving in captivity) are the former's lack of a black nape band and the red feet (black in Guam birds). The bill color is unknown due to damage to the specimen, and supposed differences in the proportion of the remiges are almost certainly an artifact of specimen preparation. Indeed, the specimen was not recognized as distinct until some 30 years after its collection.
If the bird was indeed a resident of the Miyako group (and as there was better habitat on neighboring Irabu-jima, it is probable that it would have been found there too), it became extinct in the late 19th century. While this seems early, the population must have always been small as there never
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https://en.wikipedia.org/wiki/Universal%20powerline%20bus
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Universal Powerline Bus (UPB) is a proprietary software protocol developed by Powerline Control Systems for power-line communication between devices used for home automation. Household electrical wiring is used to send digital data between UPB devices via pulse-position modulation.
Communication is peer to peer, with no central controller necessary.
UPB addressing allows 250 devices per house and 250 houses per transformer, allowing over 62,500 total device addresses and can co-exist with other powerline carrier systems within the same home.
, UPB enjoys one of the broadest range of device types when compared to most protocols and has support from some major manufacturers in the home automation space. Most notably, Leviton and their Omni series of home automation products, as well as the UPB devices they market. UPB is also supported by many major home automation software manufacturers. A few of which are listed below.
Reliability
UPB is a highly reliable protocol for home automation. It is not susceptible to RF interference, signal blockage by walls or short distance broadcast issues like some wireless protocols. UPB transmits on the building's existing wiring and has extensive noise reduction circuitry. This allows it to traverse long distances without issues, even across multiple electrical panels, making it ideal for very large homes. Appliances that have traditionally plagued X10 devices, usually do not affect UPB. In fact, UPB signals can reliably be received by the target device even with significant amounts of electrical noise on the power lines. However, in the event that an appliance in your home causes extreme interference when operating, an inexpensive wire-in noise filter can be applied at the circuit breaker panel to solve the issue.
Interoperability
, control of UPB devices is supported by the Home Assistant open source software (in version 0.110 and later).
, control of UPB devices is supported by the OpenHAB open source software.
HomeSeer
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https://en.wikipedia.org/wiki/AlphaStation
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AlphaStation is the name given to a series of computer workstations, produced from 1994 onwards by Digital Equipment Corporation, and later by Compaq and HP. As the name suggests, the AlphaStations were based on the DEC Alpha 64-bit microprocessor. Supported operating systems for AlphaStations comprise Tru64 UNIX (formerly Digital UNIX), OpenVMS and Windows NT (with AlphaBIOS ARC firmware). Most of these workstations can also run various versions of Linux and BSD operating systems.
Other Alpha workstations produced by DEC include the DEC 2000 AXP (DECpc AXP 150), the DEC 3000 AXP, the Digital Personal Workstation a-series and au-series (codename Miata), the Multia VX40/41/42 and the Alpha XL/Alpha XLT line (a member of the Alcor family, which had swappable daughterboard with Pentium processor, to transform to a DEC Celebris XL line).
Models
From the XP900 onwards, all AlphaStation models were simply workstation configurations of the corresponding AlphaServer model.
Avanti family
Alcor Family
Noritake and Rawhide Family
Tsunami Family
Titan and Marvel Family
A variant of the AlphaStation 1200 was also sold as the Digital Ultimate Workstation 533au².
Some systems had one of the microprocessors deactivated, which may be reactivated with a license upgrade.
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https://en.wikipedia.org/wiki/Attachment%20in%20children
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Attachment in children is "a biological instinct in which proximity to an attachment figure is sought when the child senses or perceives threat or discomfort. Attachment behaviour anticipates a response by the attachment figure which will remove threat or discomfort". Attachment also describes the function of availability, which is the degree to which the authoritative figure is responsive to the child's needs and shares communication with them. Childhood attachment can define characteristics that will shape the child's sense of self, their forms of emotion-regulation, and how they carry out relationships with others. Attachment is found in all mammals to some degree, especially primates.
Attachment theory has led to a new understanding of child development. Children develop different patterns of attachment based on experiences and interactions with their caregivers at a young age. Four different attachment classifications have been identified in children: secure attachment, anxious-ambivalent attachment, anxious-avoidant attachment, and disorganized attachment. Attachment theory has become the dominant theory used today in the study of infant and toddler behavior and in the fields of infant mental health, treatment of children, and related fields.
Attachment theory and children
Attachment theory (developed by the psychoanalyst Bowlby 1969, 1973, 1980) is rooted in the ethological notion that a newborn child is biologically programmed to seek proximity with caregivers, and this proximity-seeking behavior is naturally selected. Through repeated attempts to seek physical and emotional closeness with a caregiver and the responses the child gets, the child develops an internal working model (IWM) that reflects the response of the caregiver to the child. According to Bowlby, attachment provides a secure base from which the child can explore the environment, a haven of safety to which the child can return when he or she is afraid or fearful. Bowlby's colleague Mary Ai
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https://en.wikipedia.org/wiki/AlphaServer
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AlphaServer is a series of server computers, produced from 1994 onwards by Digital Equipment Corporation, and later by Compaq and HP. AlphaServers were based on the DEC Alpha 64-bit microprocessor. Supported operating systems for AlphaServers are Tru64 UNIX (formerly Digital UNIX), OpenVMS, MEDITECH MAGIC and Windows NT (on earlier systems, with AlphaBIOS ARC firmware), while enthusiasts have provided alternative operating systems such as Linux, NetBSD, OpenBSD and FreeBSD.
The Alpha processor was also used in a line of workstations, AlphaStation.
Some AlphaServer models were rebadged in white enclosures as Digital Servers for the Windows NT server market. These so-called "white box" models comprised the following:
Digital Server 3300/3305: rebadged AlphaServer 800
Digital Server 5300/5305: rebadged AlphaServer 1200
Digital Server 7300/7305/7310: rebadged AlphaServer 4100
As part of the roadmap to phase out Alpha-, MIPS- and PA-RISC-based systems in favor of Itanium-based systems at HP, the most recent AlphaServer systems reached their end of general availability on 27 April 2007. The availability of upgrades and options was discontinued on 25 April 2008, approximately one year after the systems were discontinued. Support for the most recent AlphaServer systems, the DS15A, DS25, ES45, ES47, ES80 and GS1280 is being provided by HP Services as of 2008. These systems are no longer supported by HP.
Models
In approximate chronological order, the following AlphaServer models were produced:
Avanti Family
Sable Family
The AlphaServer 2100 was briefly sold as the Digital 2100 before the AlphaServer brand was introduced.
Mikasa Family
Noritake Family
Rawhide Family
Turbolaser Family
Lynx Family
Tsunami Family
Titan Family
Wildfire Family
AlphaServer SC
The AlphaServer SC was a supercomputer constructed from a set of individual DS20L, ES40 or ES45 servers (called "nodes") mounted in racks. Every node was connected to every other node using a Quadrics el
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https://en.wikipedia.org/wiki/Attachment%20in%20adults
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In psychology, the theory of attachment can be applied to adult relationships including friendships, emotional affairs, adult romantic and carnal relationships, and, in some cases, relationships with inanimate objects ("transitional objects"). Attachment theory, initially studied in the 1960s and 1970s primarily in the context of children and parents, was extended to adult relationships in the late 1980s. The working models of children found in Bowlby's attachment theory form a pattern of interaction that is likely to continue influencing adult relationships.
Investigators have explored the organization and the stability of mental working models that underlie these attachment styles. They have also explored how attachment styles impact relationship outcomes, and how attachment styles function in relationship dynamics.
Continuing the attachment theory
Mary Ainsworth and John Bowlby founded modern attachment theory on studies of children and their caregivers. Children and caregivers remained the primary focus of attachment theory for many years. In the 1980s, Sue Johnson began using attachment theory in adult therapy. Cindy Hazan and Phillip Shaver continued to conduct research on attachment theory in adult relationships. Hazan and Shaver noticed that interactions between adults were similar to interactions between children and caregivers. For example, romantic or platonic partners desire to be close to one another, similar to how children desire to be close to their caregivers. Adults feel comforted when their attachment figures are present, and feel anxious and/or lonely when their attachment figures are absent. Romantic relationships, for example, serve as a secure base that helps people face the surprises, opportunities, and challenges life presents. Similarities such as these led Hazan and Shaver to extend attachment theory to adult relationships.
Relationships between adults also differ in some ways from relationships between children and caregivers. The clai
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https://en.wikipedia.org/wiki/Meuni%C3%A8re%20sauce
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Meunière (, , ; ) is both a French sauce and a method of preparation, primarily for fish, consisting of brown butter, chopped parsley, and lemon. The name suggests a simple rustic nature, i.e. that to cook something was originally to cook it by first dredging it in flour.
Preparation
Meunière sauce is a variation on a brown butter sauce. While there is general agreement on the addition of parsley and lemon, some include ingredients such as Worcestershire sauce, red wine vinegar, or beef stock. Another common variation is to use pecans rather than almonds in an amandine.
Fish meunière
There are two primary ways to prepare the fish (most popularly, sole or trout). One is by sautéing—first dredging the fish in seasoned flour (white flour or corn flour) and then cooking in a hot sauté pan with a small amount of clarified butter. The alternative method is to pan-fry or deep fry the floured fish. In pan frying, oil or a combination of oil and butter is used—up to perhaps 2 cm deep. Deep frying is done in either a large fry pot or in a stand-alone deep fryer. The floured fish is completely submerged in the hot oil. The frying techniques result in a crisper texture, but the sauce will need to be made separately. The sautéed fish will have a softer skin by comparison, but allows for the possibility of creating the sauce à la minute after the fish has been removed by adding fresh butter, parsley, and lemon.
Creole cuisine
Trout meunière and its variation Trout amandine (speckled seatrout crusted in almonds, traditionally served with a meunière sauce) are bedrock dishes of New Orleans Creole cuisine. The abundance of seafood from the nearby Gulf of Mexico makes the simplicity of the meunière style appropriate. Galatoire's claims to sell more Trout meunière amandine than any other dish. Soft-shell crab and redfish are also often available à la meunière. Oysters en brochette is typically served with a meuniere sauce.
See also
Piccata
Sole meunière
Notes
Sauces
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https://en.wikipedia.org/wiki/DEC%203000%20AXP
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DEC 3000 AXP was the name given to a series of computer workstations and servers, produced from 1992 to around 1995 by Digital Equipment Corporation. The DEC 3000 AXP series formed part of the first generation of computer systems based on the 64-bit Alpha AXP architecture. Supported operating systems for the DEC 3000 AXP series were DEC OSF/1 AXP (later renamed Digital UNIX) and OpenVMS AXP (later renamed OpenVMS).
All DEC 3000 AXP models used the DECchip 21064 (EV4) or DECchip 21064A (EV45) processor and inherited various features from the earlier MIPS architecture-based DECstation models, such as the TURBOchannel bus and the I/O subsystem.
The DEC 3000 AXP series was superseded in late 1994, with workstation models replaced by the AlphaStation line and server models replaced by the AlphaServer line.
Models
There were three DEC 3000 model families, codenamed Pelican, Sandpiper, and Flamingo. Within Digital, this led to the DEC 3000 series being affectionately referred to as "the seabirds".
Note: Server configurations of the Model 400/500/600/700/800/900 systems were suffixed with "S".
Description
The logic in Flamingo- and Sandpiper-based systems are contained on two modules (printed circuit boards), the CPU module and the I/O module, with the CPU module being the largest board. The two modules are connected via a 210-pin connector. The logic in Pelican-based systems are contained the CPU module and system module. The CPU module is a daughterboard that plugs into the system module and contains the CPU and the B-cache (L2 cache).
The architecture of the Flamingo- and Sandpiper-based systems is based around a crossbar switch implemented by an ADDR (Address) ASIC, four SLICE (data slice) ASICs and a TC (TURBOchannel) ASIC. These ASICs connect the various different width buses used in the system, allowing data to be transferred to the different subsystems. PALs were used to implement the control logic. The cache, memory and TURBOchannel controllers, as well
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https://en.wikipedia.org/wiki/Microbial%20genetics
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Microbial genetics is a subject area within microbiology and genetic engineering. Microbial genetics studies microorganisms for different purposes. The microorganisms that are observed are bacteria, and archaea. Some fungi and protozoa are also subjects used to study in this field. The studies of microorganisms involve studies of genotype and expression system. Genotypes are the inherited compositions of an organism. (Austin, "Genotype," n.d.) Genetic Engineering is a field of work and study within microbial genetics. The usage of recombinant DNA technology is a process of this work. The process involves creating recombinant DNA molecules through manipulating a DNA sequence. That DNA created is then in contact with a host organism. Cloning is also an example of genetic engineering.
Since the discovery of microorganisms by Robert Hooke and Antoni van Leeuwenhoek during the period 1665-1885 they have been used to study many processes and have had applications in various areas of study in genetics.
For example: Microorganisms' rapid growth rates and short generation times are used by scientists to study evolution. Robert Hooke and Antoni van Leeuwenhoek discoveries involved depictions, observations, and descriptions of microorganisms. Mucor is the microfungus that Hooke presented and gave a depiction of. His contribution being, Mucor as the first microorganism to be illustrated. Antoni van Leeuwenhoek’s contribution to the microscopic protozoa and microscopic bacteria yielded to scientific observations and descriptions. These contributions were accomplished by a simple microscope, which led to the understanding of microbes today and continues to progress scientists understanding.
Microbial genetics also has applications in being able to study processes and pathways that are similar to those found in humans such as drug metabolism.
Role in understanding evolution
Microbial genetics can focus on Charles Darwin's work and scientists have continued to study his work a
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https://en.wikipedia.org/wiki/1%3A50%20scale
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1:50 scale is a popular size for diecast models from European manufacturers such as Conrad, Tekno, NZG, WSI and LionToys. Typically they produce scale models of construction vehicles, tower cranes, trucks and buses. These are often the official models distributed by the manufacturers of the real vehicles as a promotional items for prospective customers. These models are also very popular in Europe despite their small size compared to stamped metal construction toys which are usually found in the US.
This scale is similar to O scale used in model trains and 1:50 scale will appear compatible with 1:48 scale models as produced by US manufacturers of O scale model trains and some makers of military vehicles (especially aircraft).
See also
Scale model
Diecast toy
Model car
Model commercial vehicle
Model construction vehicle
Rail transport modelling scales
Model railway scales
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https://en.wikipedia.org/wiki/Food%20and%20Agriculture%20Organization%20Corporate%20Statistical%20Database
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The Food and Agriculture Organization Corporate Statistical Database (FAOSTAT) website disseminates statistical data collected and maintained by the Food and Agriculture Organization (FAO). FAOSTAT data are provided as a time-series from 1961 in most domains for 245 countries in English, Spanish and French.
About FAOSTAT
FAOSTAT is maintained by the Statistics Division of the Food and Agriculture Organization of the United Nations. In working directly with the countries, the Statistics Division supports the development of national statistical strategies, the strengthening of Institution and technical capacities, and the improvement of statistical systems.
The FAOSTAT system is one of FAO’s most important corporate systems. It is a major component of FAO’s information systems, contributing to the organization’s strategic objective of collecting, analyzing, interpreting, and disseminating information relating to nutrition, food and agriculture for development and the fight against global hunger and malnutrition. It is at the core of the World Agricultural Information Centre (WAICENT). WAICENT gives access to FAO’s vast store of information on agricultural and food topics – statistical data, documents, books, images, and maps.
FAOSTAT Domains
Production The Agricultural Production domain covers: Produced quantities, producer prices, value at farmgate, harvested area, yield per hectare.
Trade The Agriculture Trade domain provides comprehensive, comparable, and up-to-date annual trade statistics by country, region and economic country groups for about 600 individual food and agriculture commodities since 1961. The detailed food and agriculture trade data collected, processed and disseminated by FAO according to the standard International Merchandise Trade Statistics Methodology (IMTS) are directly submitted by the national authorities to FAO or received via international or regional partner organizations. Data for missing reporters are estimated manly through the use
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https://en.wikipedia.org/wiki/History%20of%20origami
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The history of origami followed after the invention of paper and was a result of paper's use in society. In the detailed Japanese classification, origami is divided into stylized ceremonial origami (儀礼折り紙, girei origami) and recreational origami (遊戯折り紙, yūgi origami), and only recreational origami is generally recognized as origami. However, this page describes the history of both ceremonial and recreational origami.
The modern growth of interest in origami dates to the design in 1954 by Akira Yoshizawa of a notation to indicate how to fold origami models. The Yoshizawa-Randlett system is now used internationally. Today the popularity of origami has given rise to origami societies such as the British Origami Society and OrigamiUSA. The first known origami social group was founded in Zaragoza, Spain during the 1940s.
Traditional designs
Ceremonial origami (origata)
By the 7th century, paper had been introduced to Japan from China via the Korean Peninsula, and the Japanese developed washi by improving the method of making paper in the Heian period. The paper making technique developed in Japan around 805 to 809 was called nagashi-suki (流し漉き), a method of adding mucilage to the process of the conventional tame-suki (溜め漉き) technique to form a stronger layer of paper fibers. With the development of Japanese paper making technology and the widespread use of paper, folded paper began to be used for decorations and tools for religious ceremonies such as gohei, ōnusa (:ja:大麻 (神道)) and shide at Shinto shrines. Religious decorations made of paper and the way gifts were wrapped in folded paper gradually became stylized and established as ceremonial origami. During the Heian period, the Imperial court established a code of etiquette for wrapping money and goods used in ceremonies with folded paper, and a code of etiquette for wrapping gifts.
In the Muromachi period from the 1300s to the 1400s, various forms of decorum were developed by the Ogasawara clan and Ise clans (:ja:伊
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https://en.wikipedia.org/wiki/Gimme%20Shelter
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"Gimme Shelter" is a song by English rock band the Rolling Stones. It is the opening track on their 1969 album Let It Bleed. The song covers the brutal realities of war, including murder, rape and fear. It features prominent guest vocals by American singer Merry Clayton.
American author, music journalist and cultural critic Greil Marcus, writing for Rolling Stone magazine at the time of its release, praised the song, stating that the band has "never done anything better". "Gimme Shelter" has placed in various positions on many "best of/greatest" lists including that of Rolling Stone magazine. In 2021 "Gimme Shelter" was ranked at number 13 on Rolling Stones list of the "500 Greatest Songs of All Time".
Inspiration and recording
"Gimme Shelter" was written by the Rolling Stones' lead vocalist Mick Jagger and guitarist Keith Richards, the band's primary songwriting team. Richards began working on the song's signature opening riff in London while Jagger was away filming Performance with Richards' then-girlfriend, Anita Pallenberg. In his autobiography Life, Richards revealed that the tension of the song was inspired by his jealousy at seeing the relationship between Pallenberg and Jagger, and his suspicions of an affair between them.
As released, the song begins with Richards performing a guitar intro, soon joined by Jagger's lead vocal. Of Let It Bleeds bleak world view, Jagger said in a 1995 interview with Rolling Stone magazine:
Similarly, on NPR in 2012:
The song's inspiration was not initially Vietnam or social unrest, however, but Richards seeing people scurrying for shelter from a sudden rain storm. According to him:
The recording features guest vocals by Merry Clayton, recorded at a last-minute late-night recording session in Los Angeles during the mixing phase, arranged by her friend and record producer Jack Nitzsche. After the first verse is sung by Jagger, Clayton enters and they share the next three verses. A harmonica solo by Jagger and guitar sol
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https://en.wikipedia.org/wiki/Flag%20of%20Christmas%20Island
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The flag of Christmas Island was unofficially adopted in 1986 after being chosen the winner in a competition for a flag for the territory. It was designed by Tony Couch of Sydney, Australia. The flag was made official in 2002 on Australia Day, when the administrator of the territory, Bill Taylor, presented the flag to the Christmas Island Shire.
Design
The flag of Christmas Island consists of a green and blue background, split from the top left corner to the bottom right. These colours are intended to represent the land and sea respectively. The Southern Cross constellation appears in the bottom left of the flag similar to the flag of Australia. In the top right, the golden bosun bird (Phaethon lepturus fulvus, one of six subspecies of the white-tailed tropicbird) appears. It is considered to be a symbol of the Island. The last motif appears in the centre of the flag on a golden disc is the map of the island in green. The disc itself was originally only included to offset the green colour of the map, but has become linked to the mining industry.
History
Creation
In 1986, the Christmas Island Assembly announced a competition to design both a flag and a coat of arms for the territory. There was a prize fund of $100, and some 69 entries were submitted. The winning submission was created by Tony Couch, a resident of Sydney who had previously worked on Christmas Island. The new flag was announced on 14 April 1986, by the Christmas Island Assembly.
Implementation
The first attempt to make the flag official occurred in 1995 when the Minister of the Islands at the time took the view that implementation could take place on Australia Day 1996 via a formal announcement by the Administrator rather than an amendment to the Christmas Island Act 1958. Although this was agreed, the declaration never took place.
Subsequently, Christmas Island official Gary Dunt revived the issue in 2001 and the flag was formally declared the official flag of Christmas Island on Australia Day 2
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https://en.wikipedia.org/wiki/NuFW
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NuFW is a software package that extends Netfilter, the Linux kernel-internal packet filtering firewall module. NuFW adds authentication to filtering rules. NuFW is also provided as a hardware firewall, in the EdenWall firewalling appliance. NuFW has been restarted by the FFI and renamed into UFWI.
Introduction
NuFW / UFWI is an extension of Netfilter which brings the notion of user to IP filtering.
NuFW / UFWI can :
Authenticate any connection that goes through your gateway or only from/to a chosen subset or a specific protocol (iptables is used to select the connections to authenticate).
Perform accounting, routing and Quality of service (QOS) based on users and not simply on IPs.
Filter packets with criteria such as application and OS used by distant users.
Be the key of a secure and simple Single Sign On system.
Principles
NuFW / UFWI refuses the idea of IP == user as an IP address can easily be spoofed. It thus uses
its own algorithm to perform authentication. It depends on two subsystems: Nufw which is connected to Netfilter and Nuauth
which is connected to clients and Nufw.
The algorithm is the following:
A standard application sends a packet.
The Nufw client sees that a connection is being initiated and sends a user request packet.
The Nufw server queues the packet and sends an auth request packet to the Nuauth server.
The Nuauth server sums the auth request and the user request packet and checks this against an authentication authority.
The Nuauth server sends answer back to the Nufw server
The Nufw server transmits the packet following the answer given to its request.
This algorithm realizes an A Posteriori authentication of the connection. As there is no time-based association, this ensures the identity of the user who sent the packet.
NuFW is the only real Authentication firewall, as it never associates a user with his machine.
Awards
2007 : Lutèce d'Or (Paris, France), Best Innovation
2005 : Les Trophées du Libre (Soissons, Franc
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https://en.wikipedia.org/wiki/Radiation%20trapping
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Radiation trapping, imprisonment of resonance radiation, radiative transfer of spectral lines, line transfer or radiation diffusion is a phenomenon in physics whereby radiation may be "trapped" in a system as it is emitted by one atom and absorbed by another.
Classical description
Classically, one can think of radiation trapping as a multiple-scattering phenomena, where a photon is scattered by multiple atoms in a cloud. This motivates treatment as a diffusion problem. As such, one can primarily consider the mean free path of light, defined as the reciprocal of the density of scatterers and the scattering cross section:
One can assume for simplicity that the scattering diagram is isotropic, which ends up being a good approximation for atoms with equally populated sublevels of total angular momentum. In the classical limit, we can think of the electromagnetic energy density as what is being diffused. So, we consider the diffusion constant in three dimensions,
where is the transport time. The transport time accounts for both the group delay between scattering events and Wigner's delay time, which is associated with an elastic scattering process. It is written as
where is the group velocity. When the photons are near resonance, the lifetime of an excited state in the atomic vapor is equal to the transport time, , independent of the detuning. This comes in handy, since the average number of scattering events is the ratio of the time spent in the system to the lifetime of the excited state (or equivalently, the scattering time). Since in a 3D diffusion process the electromagnetic energy density spreads as , we can find the average number of scattering events for a photon before it escapes:
Finally, the number of scattering events can be related to the optical depth as follows. Since , the number of scattering events scales with the square of the optical depth.
Derivation of the Holstein equation
In 1947, Theodore Holstein attacked the problem of impr
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https://en.wikipedia.org/wiki/Citrus%20australasica
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Citrus australasica, the Australian finger lime or caviar lime, is a thorny understorey shrub or small tree of lowland subtropical rainforest and rainforest in the coastal border region of Queensland and New South Wales, Australia.
It has edible fruits which are under development as a commercially sold crop.
Description
The plant is in height. The leaves are small, long and wide, glabrous, with a notched tip and crenate towards the apex. Flowers are white with petals long. The fruit is cylindrical, long, sometimes slightly curved, coming in different colours, including pink and green.
Cultivation and uses
History
Early settlers consumed the fruit and retained the trees when clearing for agriculture. Colonial botanists suggested that they should be cultivated, due to the lack of citrus alternatives.
Rising demand
The finger lime has been recently popularised as a gourmet bushfood. The globular juice vesicles (also known as pearls) have been likened to a "lime caviar", which can be used as a garnish or added to various recipes. The fresh vesicles have the effect of a burst of effervescent tangy flavour as they are chewed. The fruit juice is acidic and similar to that of a lime. Marmalade and pickles are also made from finger lime. Finger lime peel can be dried and used as a flavouring spice.
Commercial use of finger lime fruit started in the mid-1990s with boutique marmalades made from wild harvested fruit. By 2000 the finger lime was being sold in restaurants, and exported fresh.
The finger lime has been recently grown on a commercial basis in Australia in response to high demand for the fruit. There is an increasing range of genetic selections which are budded onto citrus rootstock. With the sudden high market demand for the fruit the primary source of genetic material for propagation has been selections from wild stock.
Diseases
In cultivation, the finger lime plant is grown in much the same way as other citrus species. It may be subject to some
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https://en.wikipedia.org/wiki/Advanced%20silicon%20etching
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Advanced silicon etching (ASE) is a deep reactive-ion etching (DRIE) technique to etch deep and high aspect ratio structures in silicon. ASE was created by Surface Technology Systems Plc (STS) in 1994 in the UK. STS has continued to develop this process with faster etch rates. STS developed and first implemented the switched process, originally invented by Dr. Larmer in Bosch, Stuttgart. ASE consists in combining the faster etch rates achieved in an isotropic Si etch (usually making use of an SF6 plasma) with a deposition or passivation process (usually utilising a C4F8 plasma condensation process) by alternating the two process steps. This approach achieves the fastest etch rates while maintaining the ability to etch anisotropically, typically vertically in Microelectromechanical Systems (microelectromechanical systems (MEMS)) applications.
The ASE HRM is an improvement of the previous generations of ICP design, now incorporating a decoupled plasma source (patent pending). The decoupled source generates high-density plasma which is allowed to diffuse into a separate process chamber. Using a specialized chamber design, the excess ions (which negatively affect process control) are reduced, leaving a uniform distribution of fluorine free-radicals at a higher density than that available from the conventional ICP sources. The higher fluorine free-radical density facilitates increased etch rates, typically over three times the etch rates achieved with the original process.
Notes
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https://en.wikipedia.org/wiki/Red%20Hand%20of%20Ulster
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The Red Hand of Ulster () is a symbol used in heraldry to denote the Irish province of Ulster and the Northern Uí Néill in particular. It has also been used however by other Irish clans across the island, including the ruling families of western Connacht (i.e. the O'Flahertys and McHughs) and the chiefs of the Midlands (e.g. O'Daly, Kearney, etc.).
It is an open hand coloured red, with the fingers pointing upwards, the thumb held parallel to the fingers, and the palm facing forward. It is usually shown as a right hand, but is sometimes a left hand, such as in the coats of arms of baronets.
Historical background
The Red Hand is rooted in Gaelic culture as the sign of a great warrior. It is believed to date back to pagan times.
The Red Hand is first documented in surviving records in the 13th century, where it was used by the Hiberno-Norman de Burgh earls of Ulster. It was Walter de Burgh who became first Earl of Ulster in 1243 who combined the de Burgh cross with the Red Hand to create a flag that represented the Earldom of Ulster and later became the modern Flag of Ulster.
It was afterwards adopted by the O'Neills when they assumed the ancient kingship of Ulster, inventing the title Rex Ultonie (king of Ulster) for themselves in 1317 and then claiming it unopposed from 1345 onwards. An early Irish heraldic use in Ireland of the open right hand can be seen in the seal of Aodh Reamhar Ó Néill, king of the Irish of Ulster, 1344–1364.
An early-15th-century poem by Mael Ó hÚigínn is named , the first line of which is a variation of the title: "", translated as "The Úí Eachach are the 'red hand' of Ireland". The Uí Eachach were one of the Cruthin tribes (known as the Dál nAraidi after 773) that made up the ancient kingdom of Ulaid.
The Red Hand symbol is believed to have been used by the O'Neills during its Nine Years' War (1594–1603) against English rule in Ireland, and the war cry ! ("the Red Hand of Ireland to victory") was also associated with them. An English
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https://en.wikipedia.org/wiki/1%3A48%20scale
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1:48 scale is a scale commonly used in diecast models, plastic models made from kits, and construction toys. It is especially popular with manufacturers of model aircraft and model trains, where it is known as "O scale". 1:48 is also a popular scale among Lego enthusiasts, since it is approximately the scale of the Lego minifigure.
At this scale, inch represents 1 foot. It is similar in size to 1:50 scale and 1:43 scale, which are popular for diecast vehicles.
In 2003, Tamiya began to manufacture a line of military ground vehicle models in 1:48 in addition to their more traditional 1:35 scale line. This has been seen as an attempt to break into a new market due to the stiff competition in the larger scale.
Bandai also produces giant robots in this size, called Mega Size.
See also
Die-cast toy
Rail transport modelling scales
Scale model
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https://en.wikipedia.org/wiki/Lebesgue%20differentiation%20theorem
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In mathematics, the Lebesgue differentiation theorem is a theorem of real analysis, which states that for almost every point, the value of an integrable function is the limit of infinitesimal averages taken about the point. The theorem is named for Henri Lebesgue.
Statement
For a Lebesgue integrable real or complex-valued function f on Rn, the indefinite integral is a set function which maps a measurable set A to the Lebesgue integral of , where denotes the characteristic function of the set A. It is usually written
with λ the n–dimensional Lebesgue measure.
The derivative of this integral at x is defined to be
where |B| denotes the volume (i.e., the Lebesgue measure) of a ball B centered at x, and B → x means that the diameter of B tends to 0.
The Lebesgue differentiation theorem states that this derivative exists and is equal to f(x) at almost every point x ∈ Rn. In fact a slightly stronger statement is true. Note that:
The stronger assertion is that the right hand side tends to zero for almost every point x. The points x for which this is true are called the Lebesgue points of f.
A more general version also holds. One may replace the balls B by a family of sets U of bounded eccentricity. This means that there exists some fixed c > 0 such that each set U from the family is contained in a ball B with . It is also assumed that every point x ∈ Rn is contained in arbitrarily small sets from . When these sets shrink to x, the same result holds: for almost every point x,
The family of cubes is an example of such a family , as is the family (m) of rectangles in R2 such that the ratio of sides stays between m−1 and m, for some fixed m ≥ 1. If an arbitrary norm is given on Rn, the family of balls for the metric associated to the norm is another example.
The one-dimensional case was proved earlier by . If f is integrable on the real line, the function
is almost everywhere differentiable, with Were defined by a Riemann integral this would be essenti
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https://en.wikipedia.org/wiki/1%3A64%20scale
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1:64 scale is a traditional scale for models and miniatures, in which one unit (such as an inch or a centimeter) on the model represents 64 units on the actual object. It is also known as "three-sixteenths scale", since 3/16 of an inch represents one foot. A human is approximately tall in 1:64 scale. The scale originated by halving the very common 1:32 scale, which was known as "standard size" in some hobbies.
This scale became successful because of its relative size in comparison to other toys, the fact that it is a derivative of 1/16 scale, and because they are easily held by small hands. The 1/64 scale models will generally have less detail than a 1/16 scale models. Moreover, "1/64 coincides with the S scale of model railroading, part of the consideration of why 1/64 became an established size."
Currently, 1:64 scale is most commonly used for automobile and other vehicle models, but it is also a popular scale for model railroads and toy trains, and has been used for ship models also. In addition, 28mm military and fantasy figures are a popular size for tabletop gaming, and they are sometimes scaled out to 1:64, although opinion on the actual scale of 28mm range from 1:48 to 1:64 with 1:56 being the most common.
Die-cast vehicles
Many diecast automobiles and commercial vehicle models for collectors have been made to a strict scale of 1:64. However, for much of the die-cast toy market, 1:64 is only a nominal scale. Though collectors and manufacturers loosely describe popular lines of die-casts as 1:64, toy vehicles are usually made to "box scale." This means that the size of the model is determined by the size of the standard packaging (formerly a cardstock box, now usually a clear blister-card). Models of a 1959 Cadillac and an Austin Mini-Cooper designed to fill up the same packaging space will have very different actual scales, but for the passenger automobiles in many die-cast lines, 1:64 is a reasonable approximation. Brands of die-cast toys in and around
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https://en.wikipedia.org/wiki/Zsigmondy%27s%20theorem
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In number theory, Zsigmondy's theorem, named after Karl Zsigmondy, states that if are coprime integers, then for any integer , there is a prime number p (called a primitive prime divisor) that divides and does not divide for any positive integer , with the following exceptions:
, ; then which has no prime divisors
, a power of two; then any odd prime factors of must be contained in , which is also even
, , ; then
This generalizes Bang's theorem, which states that if and is not equal to 6, then has a prime divisor not dividing any with .
Similarly, has at least one primitive prime divisor with the exception .
Zsigmondy's theorem is often useful, especially in group theory, where it is used to prove that various groups have distinct orders except when they are known to be the same.
History
The theorem was discovered by Zsigmondy working in Vienna from 1894 until 1925.
Generalizations
Let be a sequence of nonzero integers.
The Zsigmondy set associated to the sequence is the set
i.e., the set of indices such that every prime dividing also divides some for some . Thus Zsigmondy's theorem implies that , and Carmichael's theorem says that the Zsigmondy set of the Fibonacci sequence is , and that of the Pell sequence is . In 2001 Bilu, Hanrot, and Voutier
proved that in general, if is a Lucas sequence or a Lehmer sequence, then (see , there are only 13 such s, namely 1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 13, 18, 30).
Lucas and Lehmer sequences are examples of divisibility sequences.
It is also known that if is an elliptic divisibility sequence, then its Zsigmondy
set is finite. However, the result is ineffective in the sense that the proof does not give an explicit upper bound for the largest element in ,
although it is possible to give an effective upper bound for the number of elements in .
See also
Carmichael's theorem
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https://en.wikipedia.org/wiki/Pepper%20Pad
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The Pepper Pad was a family of Linux-based mobile computers with Internet capability and which doubled as a handheld game console. They also served as a portable multimedia device. The devices used Bluetooth and Wi-Fi technologies for Internet connection. Pepper Pads are now obsolete, unsupported and the parent company has ceased operations.
The original prototype Pepper Pad was built in 2003 with an ARM-based PXA255 processor running at 400Mhz, an 8-inch touchscreen in portrait mode, a split QWERTY keyboard, and Wi-Fi. Only 6 were made, and it was never offered for sale. The Pepper Pad was a 2004 Consumer Electronics Show (CES) Innovations Awards Honoree in the Computer Hardware category.
The Pepper Pad 2 was introduced in 2004 with a faster 624Mhz PXA270 processor and the screen was rotated to a landscape format. The Pepper Pad 2 was the first Pepper Pad offered for commercial sale. The Pepper Pad and Pepper Pad 2 both ran Pepper's proprietary Pepper Keeper application on top of a heavily customized version of the Montavista Linux operating system.
The Pepper Pad 3 was announced in 2006 with as upgrade to a faster AMD Geode processor. The Pepper Pad 3 also used a smaller 7" screen for cost savings. Like previous versions, the Pepper Pad 3 had a split QWERTY button keyboard, built-in microphone, video camera, composite video output, and stereo speakers, Infra-Red receiver and transmitter, 800x480 7 inch LCD touchscreen (with stylus), SD/MMC Flash memory slot, 20 or 30 GB hard disk, 256MB RAM, 256KB ROM, and both Wi-Fi (b/g) and Bluetooth 2.0. The Pepper Pad 3 used a heavily customized version of the Fedora Linux operating system called Pepper Linux. Unlike the Pepper Pad 2 which was built and sold directly by Pepper, the Pepper Pad 3 was built and sold under license by Hanbit Electronics.
Support
Pepper Computer, Inc. has ceased operations and is no longer providing support or sales for Pepper Pad web computers or Pepper Linux.
Software
Pepper Pads ran Pepp
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https://en.wikipedia.org/wiki/Frequency%20divider
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A frequency divider, also called a clock divider or scaler or prescaler, is a circuit that takes an input signal of a frequency, , and generates an output signal of a frequency:
where is an integer. Phase-locked loop frequency synthesizers make use of frequency dividers to generate a frequency that is a multiple of a reference frequency. Frequency dividers can be implemented for both analog and digital applications.
Analog
Analog frequency dividers are less common and used only at very high frequencies. Digital dividers implemented in modern IC technologies can work up to tens of GHz.
Regenerative
A regenerative frequency divider, also known as a Miller frequency divider, mixes the input signal with the feedback signal from the mixer.
The feedback signal is . This produces sum and difference frequencies , at the output of the mixer. A low pass filter removes the higher frequency, and the frequency is amplified and fed back into the mixer.
Injection-locked
A free-running oscillator which has a small amount of a higher-frequency signal fed to it, will tend to oscillate in step with the input signal. Such frequency dividers were essential in the development of television.
It operates similarly to an injection locked oscillator. In an injection-locked frequency divider, the frequency of the input signal is a multiple (or fraction) of the free-running frequency of the oscillator. While these frequency dividers tend to be lower power than broadband static (or flip-flop-based) frequency dividers, the drawback is their low locking range. The ILFD locking range is inversely proportional to the quality factor (Q) of the oscillator tank. In integrated circuit designs, this makes an ILFD sensitive to process variations. Care must be taken to ensure the tuning range of the driving circuit (for example, a voltage-controlled oscillator) must fall within the input locking range of the ILFD.
Digital
For power-of-2 integer division, a simple binary counter can be u
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https://en.wikipedia.org/wiki/1%3A43%20scale
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1:43 scale is a popular size of die-cast model cars in Europe, Asia and the US. It has its origins in the British / European O scale for model trains and the rise of certain accessories made for that scale which since have become popular in their own right. Models in this scale are 10–13 cm length (3.93–5.11 inches).
Variations in the scale
There are many manufacturers in 1:43 scale producing everything from customized and accurate race cars to emergency vehicles, family sedans and SUVs. Trucks and tractor trailers can also be found in this scale, but they are comparatively larger and 1:50 or 1:64 scales are more common for these types of vehicles.
Related train scales are 1:42, 1:48 (American O scale), and also 1:45 scale (NEM European 0 scale), which is only slightly larger than 1:50 scale. Items in all these scales are similar enough in size that they are commonly used together in O layouts.
European history
The first model car made exactly to 1:43 scale seems to be French Dinky Toys No. 24R Peugeot 203, released in 1951, but many diecast iron or plaster toys in the 1920s and 1930s were also made about the same size, though not as precision 'blueprint' reproductions. As a representative example, a Volkswagen Beetle in 1:43 scale measures about 3.5 inches (90 millimeters) in length. Larger cars might measure 4 to 4.5 inches (100 to 115 millimeters) if reproduced to 1:43 scale.
Countries to first produce this scale were mainly France and the United Kingdom, but Germany and Italy were also homes for the common producers. From the 1950s through the 1980s, 1:43 was primarily used in European toy offerings such as Corgi Toys, Dinky Toys, Schuco, Tekno, Solido, Mercury, Polistil, and Mebetoys.
Metosul of Portugal in the mid-1960s was one of the first diecast toy companies to use tooling (or at least precisely similar designs) from a larger, more well-known company – Dinky in this case. This was the beginning of a trend that would spread across southern Europe to
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https://en.wikipedia.org/wiki/Cross-entropy%20method
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The cross-entropy (CE) method is a Monte Carlo method for importance sampling and optimization. It is applicable to both combinatorial and continuous problems, with either a static or noisy objective.
The method approximates the optimal importance sampling estimator by repeating two phases:
Draw a sample from a probability distribution.
Minimize the cross-entropy between this distribution and a target distribution to produce a better sample in the next iteration.
Reuven Rubinstein developed the method in the context of rare event simulation, where tiny probabilities must be estimated, for example in network reliability analysis, queueing models, or performance analysis of telecommunication systems. The method has also been applied to the traveling salesman, quadratic assignment, DNA sequence alignment, max-cut and buffer allocation problems.
Estimation via importance sampling
Consider the general problem of estimating the quantity
,
where is some performance function and is a member of some parametric family of distributions. Using importance sampling this quantity can be estimated as
,
where is a random sample from . For positive , the theoretically optimal importance sampling density (PDF) is given by
.
This, however, depends on the unknown . The CE method aims to approximate the optimal PDF by adaptively selecting members of the parametric family that are closest (in the Kullback–Leibler sense) to the optimal PDF .
Generic CE algorithm
Choose initial parameter vector ; set t = 1.
Generate a random sample from
Solve for , where
If convergence is reached then stop; otherwise, increase t by 1 and reiterate from step 2.
In several cases, the solution to step 3 can be found analytically. Situations in which this occurs are
When belongs to the natural exponential family
When is discrete with finite support
When and , then corresponds to the maximum likelihood estimator based on those .
Continuous optimization—example
The same CE algorithm
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https://en.wikipedia.org/wiki/Hitsuzend%C5%8D
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is believed by Zen Buddhists to be a method of achieving samādhi (Japanese: 三昧 sanmai), which is a unification with the highest reality. Hitsuzendo refers specifically to a school of Japanese Zen calligraphy to which the rating system of modern calligraphy (well-proportioned and pleasing to the eye) is foreign. Instead, the calligraphy of Hitsuzendo must breathe with the vitality of eternal experience.
Origins
Yokoyama Tenkei (1885–1966), inspired by the teachings of Yamaoka Tesshu (1836–1888), founded the Hitsuzendo line of thought as a "practice to uncover one's original self through the brush." This was then further developed by Omori Sogen Roshi as a way of Zen practice. Hitsuzendo is practised standing, using a large brush and ink, usually on newspaper roll. In this way, the whole body is used to guide the brush, in contrast to writing at a table.
History
Calligraphy was brought to Japan from China and Chinese masters such as Wang Xizhi 王羲之 (Jp: Ou Gishi; 303-361) have had a profound influence, especially on the karayō style which is still practiced today. The indigenous Japanese wayō tradition (和様書道, wayō-shodō) only appeared towards the end of the Heian era. However, the calligraphy of Zen scholars was often more concerned with spiritual qualities and individual expression and shunned technicalities which led to unique and distinctly personal styles. Japanese calligraphy has three basic styles: Kaisho 楷書, Gyōsho 行書, and Sōsho 草書, adopted from China.
Philosophical background
True creativity is not the product of consciousness but rather the "phenomenon of life itself." True creation must arise from mu-shin 無心, the state of "no-mind," in which thought, emotions, and expectations do not matter. Truly skillful Zen calligraphy is not the product of intense "practice;" rather, it is best achieved as the product of the "no-mind" state, a high level of spirituality, and a heart free of disturbances.
To write Zen calligraphic characters that convey truly deep me
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https://en.wikipedia.org/wiki/Semi-deciduous
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Semi-deciduous or semi-evergreen is a botanical term which refers to plants that lose their foliage for a very short period, when old leaves fall off and new foliage growth is starting. This phenomenon occurs in tropical and sub-tropical woody species, for example in Dipteryx odorata. Semi-deciduous or semi-evergreen may also describe some trees, bushes or plants that normally only lose part of their foliage in autumn/winter or during the dry season, but might lose all their leaves in a manner similar to deciduous trees in an especially cold autumn/winter or severe dry season (drought).
See also
Brevideciduous
Evergreen
Marcescence
Hedera
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https://en.wikipedia.org/wiki/Carrier%20recovery
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A carrier recovery system is a circuit used to estimate and compensate for frequency and phase differences between a received signal's carrier wave and the receiver's local oscillator for the purpose of coherent demodulation.
In the transmitter of a communications carrier system, a carrier wave is modulated by a baseband signal. At the receiver, the baseband information is extracted from the incoming modulated waveform.
In an ideal communications system, the carrier signal oscillators of the transmitter and receiver would be perfectly matched in frequency and phase, thereby permitting perfect coherent demodulation of the modulated baseband signal.
However, transmitters and receivers rarely share the same carrier oscillator. Communications receiver systems are usually independent of transmitting systems and contain their oscillators with frequency and phase offsets and instabilities. Doppler shift may also contribute to frequency differences in mobile radio frequency communications systems.
All these frequencies and phase variations must be estimated using the information in the received signal to reproduce or recover the carrier signal at the receiver and permit coherent demodulation.
Methods
For a quiet carrier or a signal containing a dominant carrier spectral line, carrier recovery can be accomplished with a simple band-pass filter at the carrier frequency or with a phase-locked loop, or both.
However, many modulation schemes make this simple approach impractical because most signal power is devoted to modulation—where the information is present—and not to the carrier frequency. Reducing the carrier power results in greater transmitter efficiency. Different methods must be employed to recover the carrier in these conditions.
Non-data-aided
Non-data-aided/“blind” carrier recovery methods do not rely on knowledge of the modulation symbols. They are typically used for simple carrier recovery schemes or as the initial coarse carrier frequency recovery meth
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https://en.wikipedia.org/wiki/Handheld%20television
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A handheld television is a portable device for watching television that usually uses a TFT LCD or OLED and CRT color display. Many of these devices resemble handheld transistor radios.
History
In 1970, Panasonic released the first TV which was small enough to fit in a large pocket; called the Panasonic IC TV MODEL TR-001 and Sinclair Research released the second pocket television, the MTV-1. Since LCD technology was not yet mature at the time, the TV used a minuscule CRT which set the record for being the smallest CRT on a commercially marketed product.
Later in 1982, Sony released their first model - the FD-200, which was introduced as “Flat TV” later renamed after the nickname Watchman, a play on the word Walkman. It had grayscale video at first. Several years later, a color model with an active-matrix LCD was released. Some smartphones integrate a television receiver, although Internet broadband video is far more common.
Since the switch-over to digital broadcasting, handheld TVs have reduced in size and improved in quality. Portable TV was eventually brought to digital TV with DVB-H, although it didn't see much success. The major current manufacturers of DVB-T standard (common throughout Europe) handheld TVs are August International, ODYS and Xoro.
Hardware
These devices often have stereo 1⁄8 inch (3.5 mm) phono plugs for composite video-analog mono audio relay to serve them as composite monitors; also, some models have mono 3.5 mm jacks for the broadcast signal that is usually relayed via F connector or Belling-Lee connector on standard television models.
Some include HDMI, USB and SD ports.
Screen sizes vary from . Some handheld televisions also double as portable DVD players and USB personal video recorders.
Size
Portable televisions cannot fit in a pocket, but often run on batteries and include a cigarette lighter receptacle plug.
Pocket televisions fit in a pocket.
Wearable televisions sometimes are made in the form of a wristwatch.
Notab
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https://en.wikipedia.org/wiki/OpenGrok
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OpenGrok is a source code search and cross-reference engine. It helps programmers to search, cross-reference, and navigate source code trees to aid code comprehension.
It can understand various program file formats and version control histories such as Monotone, SCCS, RCS, CVS, Subversion, Mercurial, Git, Clearcase, Perforce, and Bazaar.
The name comes from the term grok, a computing jargon term meaning 'intuitive understanding.'
OpenGrok is being developed mainly by the community with the help of a few engineers from Oracle Corporation (which absorbed Sun Microsystems). OpenGrok is released under the terms of the Common Development and Distribution License (CDDL).
It is mainly written in Java, with some tooling done in Python. It relies on the analysis done by Ctags. There is an official Docker image available.
Features
OpenGrok supports:
Full text Search
Definition Search
Identifier Search
Path search
History Search
Shows matching lines
Hierarchical Search
query syntax like AND, OR, field:
Incremental update
Syntax highlighting cross references (Xref)
Quick navigation inside the file
Interface for SCM
Usable URLs
Individual file download
Changes at directory level
Multi language support
Suggester
RESTful API
See also
LXR Cross Referencer
ViewVC
FishEye (software)
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https://en.wikipedia.org/wiki/Sony%20NEWS
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The Sony NEWS ("Network Engineering Workstation", later "NetWorkStation") is a series of Unix workstations sold during the late 1980s and 1990s. The first NEWS machine was the NWS-800, which originally appeared in Japan in January 1987 and was conceived as a desktop replacement for the VAX series of minicomputers.
History
1980s
Sony's NEWS project leader, Toshitada Doi, originally wanted to develop a computer for business applications, but his engineers wanted to develop a replacement for minicomputers running Unix that they preferred to use:
Initial development of the NEWS was completed in 1986 after only one year of development. It launched at a lower price than competitors (–16,300), and it outperformed conventional minicomputers. After a successful launch, the line expanded and the new focus for the NEWS became desktop publishing and CAD/CAM.
1990s
In 1991, Sony broadened the NEWS range with the 3250 portable workstation, reportedly described in product literature as a laptop but weighing 18 pounds and having more in common with portable computers, being "designed to be set up on a desk and plugged in". Featuring an 11-inch monochrome liquid crystal display with a resolution of and keyboard with "75 full travel keys", the machine was fitted with an internal hard drive and a 3.5-inch floppy drive. A SCSI port permitted the addition of other storage devices, and Ethernet, parallel and serial ports were provided, along with a mouse port and audio in/out ports for audio processing. In terms of its fundamental computing facilities, the system employed a 20 MHz MIPS R3000 CPU with R3010 floating-point coprocessor, offered 8 MB of RAM expandable to 36 MB, running an implementation of Unix System V Release 4 and providing an Open Software Foundation Motif graphical environment. In the United States, a configuration with 240 MB hard drive cost $9,900, with the 406 MB configuration costing $11,900.
Early PlayStation development kits were based on Sony NEWS hardware,
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https://en.wikipedia.org/wiki/Gluster
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Gluster Inc. (formerly known as Z RESEARCH) was a software company that provided an open source platform for scale-out public and private cloud storage. The company was privately funded and headquartered in Sunnyvale, California, with an engineering center in Bangalore, India. Gluster was funded by Nexus Venture Partners and Index Ventures. Gluster was acquired by Red Hat on October 7, 2011.
History
The name Gluster comes from the combination of the terms GNU and cluster. Despite the similarity in names, Gluster is not related to the Lustre file system and does not incorporate any Lustre code.
Gluster based its product on GlusterFS, an open-source software-based network-attached filesystem that deploys on commodity hardware. The initial version of GlusterFS was written by Anand Babu Periasamy, Gluster's founder and CTO.
In May 2010 Ben Golub became the president and chief executive officer.
Red Hat became the primary author and maintainer of the GlusterFS open-source project after acquiring the Gluster company in October 2011.
The product was first marketed as Red Hat Storage Server, but in early 2015 renamed to be Red Hat Gluster Storage since Red Hat has also acquired the Ceph file system technology.
Red Hat Gluster Storage is in the retirement phase of its lifecycle with a end of support life date of December 31, 2024.
Architecture
The GlusterFS architecture aggregates compute, storage, and I/O resources into a global namespace. Each server plus attached commodity storage (configured as direct-attached storage, JBOD, or using a storage area network) is considered to be a node. Capacity is scaled by adding additional nodes or adding additional storage to each node. Performance is increased by deploying storage among more nodes. High availability is achieved by replicating data n-way between nodes.
Public cloud deployment
For public cloud deployments, GlusterFS offers an Amazon Web Services (AWS) Amazon Machine Image (AMI), which is deployed on Elastic Comput
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https://en.wikipedia.org/wiki/ILiad
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The iLiad was an electronic handheld device, or e-Reader, which could be used for document reading and editing. Like the Barnes and Noble nook, Sony Reader or Amazon Kindle, the iLiad made use of an electronic paper display. In 2010, sales of the iLiad ended when its parent company, iRex Technologies, filed for bankruptcy.
Description
Main specifications:
electronic paper display, area for displaying content is 124x165mm
resolution of 768x1024 pixels, 160 dpi
16 levels of grayscale
USB connector for external storage
CompactFlash Type II slot for memory extension or other applications
MultiMediaCard slot for MMC memory cards
3.5 mm stereo audio jack for a headset
WiFi 802.11g wireless LAN
10/100 Mbit/s wired LAN
weight
400 MHz Intel XScale processor
64 MB RAM
256 MB internal flash memory, 128 for user, 128 for system
Linux-based operating system, 2.4 kernel
SDK provided, so functionality is easily extended
It measures 155 × 216 × 16 mm (width × height × depth), the size of an A5 document, or roughly a 6"×9" steno notebook. The display used is an active matrix electrophoretic display, which uses E Ink Vizplex Imaging Film manufactured by E Ink Corporation. Underneath the E Ink screen is a digitizing tablet by WACOM which requires a stylus for input. When it was introduced, the Iliad had largest screen size of existing e-paper products, but the newer iRex Digital Reader 1000's display is the largest sold as of early 2011.
The iLiad can display document files in several formats, including PDF, Mobipocket, XHTML and plain text. It can also display JPEG, BMP and PNG images, but not in color. As of May 3, 2007 Mobipocket is supported, making the mobipocket digital rights management (DRM) content available on this platform. iRex's product page for the iLiad states that "Support for additional E-book formats will become available over the coming months."
Through its wireless service, iDS, the iLiad can also directly download content. Les Echos, a F
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https://en.wikipedia.org/wiki/Display%20%28zoology%29
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Display behaviour is a set of ritualized behaviours that enable an animal to communicate to other animals (typically of the same species) about specific stimuli. Such ritualized behaviours can be visual, but many animals depend on a mixture of visual, audio, tactical and chemical signals. Evolution has tailored these stereotyped behaviours to allow animals to communicate both conspecifically and interspecifically which allows for a broader connection in different niches in an ecosystem. It is connected to sexual selection and survival of the species in various ways. Typically, display behaviour is used for courtship between two animals and to signal to the female that a viable male is ready to mate. In other instances, species may make territorial displays, in order to preserve a foraging or hunting territory for its family or group. A third form is exhibited by tournament species in which males will fight in order to gain the 'right' to breed. Animals from a broad range of evolutionary hierarchies avail of display behaviours - from invertebrates such as the simple jumping spider to the more complex vertebrates like the harbour seal.
In animals
Invertebrates
Insects
Communication is important for animals throughout the animal kingdom. For example, since female praying mantids are sexually cannibalistic, the male typically uses a cryptic form of display. This is a series of creeping movements executed by the male as it approaches the female, with freezing whenever the female looks towards the male. However, according to laboratory studies conducted by Loxton in 1979, one type of mantis, Ephestiasula arnoena, shows both male and female counterparts performing overt and ritualized behaviour before mating. Both displayed a semaphore behaviour, meaning waving their front legs in a boxing fashion before the slow approach of the male from behind. This semaphore display communicates that both are ready for copulation.
Flies belonging to the genus Megaselia also show s
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https://en.wikipedia.org/wiki/Matthieu%20Brouard
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Matthieu Brouard was a French theologian, mathematician, philosopher and historian, who was born in Saint-Denis near Paris in 1520, and died in Geneva on July 15, 1576. He is also known as Matthieu Brouart or Béroalde and (in Latin) as Mattheus Beroaldus. He taught Greek to the young Thomas Bodley and was the father of François Béroalde de Verville.
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https://en.wikipedia.org/wiki/Tetrasodium%20EDTA
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Tetrasodium EDTA is the salt resulting from the neutralization of ethylenediaminetetraacetic acid with four equivalents of sodium hydroxide (or an equivalent sodium base). It is a white solid that is highly soluble in water. Commercial samples are often hydrated, e.g. Na4EDTA.4H2O. The properties of solutions produced from the anhydrous and hydrated forms are the same, provided they are at the same pH.
It is used as a source of the chelating agent EDTA4-. A 1% aqueous solution has a pH of approximately 11.3. When dissolved in neutral water, it converts partially to H2EDTA2-. Ethylenediaminetetraacetic acid is produced commercially via the intermediacy of tetrasodium EDTA.
Products
The substance is also known as Dissolvine E-39. It is a salt of edetic acid. It has been known at least since 1954. It is sometimes used as a chelating agent.
The assignee on 5% of patents at the USPTO containing the substance is the firm Procter and Gamble. It is used most notably in cosmetics and hair and skin care products.
The substance has been used to aid in formulation of a removal product for rust, corrosion, and scale from ferrous metal, copper, brass, and other surfaces.
At a concentration of 6%, it is the main active ingredient in some types of engine coolant system flushes.
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https://en.wikipedia.org/wiki/Importin
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Importin is a type of karyopherin that transports protein molecules from the cell's cytoplasm to the nucleus. It does so by binding to specific recognition sequences, called nuclear localization sequences (NLS).
Importin has two subunits, importin α and importin β. Members of the importin-β family can bind and transport cargo by themselves, or can form heterodimers with importin-α. As part of a heterodimer, importin-β mediates interactions with the pore complex, while importin-α acts as an adaptor protein to bind the nuclear localization signal (NLS) on the cargo. The NLS-Importin α-Importin β trimer dissociates after binding to Ran GTP inside the nucleus, with the two importin proteins being recycled to the cytoplasm for further use.
Discovery
Importin can exist as either a heterodimer of importin-α/β or as a monomer of Importin-β. Importin-α was first isolated in 1994 by a group including Enno Hartmann, based at the Max Delbrück Center for Molecular Medicine. The process of nuclear protein import had already been characterised in previous reviews, but the key proteins involved had not been elucidated up until that point. A 60 kDa cytosolic protein, essential for protein import into the nucleus, and with a 44% sequence identity to SRP1p, was purified from Xenopus eggs. It was cloned, sequenced and expressed in E.coli and in order to completely reconstitute signal dependent transport, had to be combined with Ran(TC4). Other key stimulatory factors were also found in the study.
Importin-β, unlike importin-α, has no direct homologues in yeast, but was purified as a 90-95 kDa protein and found to form a heterodimer with importin-α in a number of different cases. These included a study led by Michael Rexach
and further studies by Dirk Görlich. These groups found that importin-α requires another protein, importin-β to function, and that together they form a receptor for nuclear localization signals (NLS), thus allowing transport into the nucleus. Since these initial d
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https://en.wikipedia.org/wiki/Lakes%20of%20Wada
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In mathematics, the are three disjoint connected open sets of the plane or open unit square with the counterintuitive property that they all have the same boundary. In other words, for any point selected on the boundary of one of the lakes, the other two lakes' boundaries also contain that point.
More than two sets with the same boundary are said to have the Wada property; examples include Wada basins in dynamical systems. This property is rare in real-world systems.
The lakes of Wada were introduced by , who credited the discovery to Takeo Wada. His construction is similar to the construction by of an indecomposable continuum, and in fact it is possible for the common boundary of the three sets to be an indecomposable continuum.
Construction of the lakes of Wada
The Lakes of Wada are formed by starting with a closed unit square of dry land, and then digging 3 lakes according to the following rule:
On day n = 1, 2, 3,... extend lake n mod 3 (= 0, 1, 2) so that it is open and connected and passes within a distance 1/n of all remaining dry land. This should be done so that the remaining dry land remains homeomorphic to a closed unit square.
After an infinite number of days, the three lakes are still disjoint connected open sets, and the remaining dry land is the boundary of each of the 3 lakes.
For example, the first five days might be (see the image on the right):
Dig a blue lake of width 1/3 passing within /3 of all dry land.
Dig a red lake of width 1/32 passing within /32 of all dry land.
Dig a green lake of width 1/33 passing within /33 of all dry land.
Extend the blue lake by a channel of width 1/34 passing within /34 of all dry land. (The small channel connects the thin blue lake to the thick one, near the middle of the image.)
Extend the red lake by a channel of width 1/35 passing within /35 of all dry land. (The tiny channel connects the thin red lake to the thick one, near the top left of the image.)
A variation of this construction can produce
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https://en.wikipedia.org/wiki/Zinc%20finger%20FYVE%20domain-containing%20protein%209
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Zinc finger FYVE domain-containing protein 9 or SARA (SMAD anchor for receptor activation) is a protein that in humans is encoded by the ZFYVE9 gene. SARA contains a double zinc finger (FYVE domain).
SARA is an anchoring protein involved in TGF beta signaling. It binds to the MH2 domain of the R-SMADs SMAD2 and SMAD3 as well as the type I TGF beta receptors. It facilitates the phosphorylation of the R-SMAD, which subsequently dissociates from SARA and the receptor and binds a coSMAD where they enter the nucleus as transcription factors.
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https://en.wikipedia.org/wiki/Google%20Pay%20Send
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Google Pay Send, previously known as Google Wallet, was a peer-to-peer payments service developed by Google before its merger into Google Pay. It allowed people to send and receive money from a mobile device or desktop computer.
In 2018, Android Pay and Google Wallet were unified into a single pay system called Google Pay. The old Wallet app was rebranded Google Pay Send, before it was discontinued as well in 2020.
Service
Google Pay is structured to allow its patrons to send money to each other. To send money, a Google Pay user enters the email address or phone number of the recipient. The recipient must then link that phone number or email address to a bank account in order to access those funds. If the recipient also has a Google Pay account, the funds will post to that account directly.
Users can link up to two bank accounts when the Wallet account is created. Received money goes to the Google Pay Balance and stays there until the user decides to cash out to a linked account.
The Google Pay app is available for free from either Google Play or the App Store. After downloading the app, the user creates a four-digit personal identification number (PIN) for managing everything within their Google Pay account. The PIN verifies access to the Wallet app on the user's mobile device.
Before it was discontinued on June 30, 2016, the Google Wallet Card was recognized by the Cirrus network operated by MasterCard (rather than the Plus network operated by Visa).
In September 2017, Google launched its first major payments service outside the United States, in Tez, India.
History
Early history
Google demonstrated the original version of the service at a press conference on May 26, 2011. The first app was released in the US only on September 19, 2011. Initially, the app only supported Mastercard cards issued by Citibank.
On May 15, 2013, Google announced the integration of Google Wallet and Gmail, allowing users to send money through Gmail attachments. While Google Wa
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https://en.wikipedia.org/wiki/Hypromellose
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Hypromellose (INN), short for hydroxypropyl methylcellulose (HPMC), is a semisynthetic, inert, viscoelastic polymer used in eye drops, as well as an excipient and controlled-delivery component in oral medicaments, found in a variety of commercial products.
As a food additive, hypromellose is an emulsifier, thickening and suspending agent, and an alternative to animal gelatin. Its Codex Alimentarius code (E number) is E464.
Chemistry
Hypromellose is a solid, and is a slightly off-white to beige powder in appearance and may be formed into granules. The compound forms colloids when dissolved in water. This non-toxic ingredient is combustible and can react vigorously with oxidizing agents.
Hypromellose in an aqueous solution, like methylcellulose, exhibits a thermal gelation property. That is, when the solution heats up to a critical temperature, the solution congeals into a non-flowable but semi-flexible mass. Typically, this critical (congealing) temperature is inversely related to both the solution concentration of HPMC and the concentration of the methoxy group within the HPMC molecule (which in turn depends on both the degree of substitution of the methoxy group and the molar substitution). That is, the higher the concentration of the methoxy group, the lower the critical temperature. The inflexibility/viscosity of the resulting mass, however, is directly related to the concentration of the methoxy group (the higher the concentration is, the more viscous or less flexible the resulting mass is).
Uses
There are many fields of application for hypromellose, including:
Tile adhesives
Cement renders
Gypsum products
Pharmaceutical
Paints and coatings
Food
Cosmetics
Detergents and cleaners
Eye drops
Contact lenses
Polyvinyl Chloride (PVC)
Use in whole grain breads
Agricultural Research Service scientists are investigating using the plant-derived HPMC as a substitute for gluten in making all-oat and other grain breads. Gluten, which is present in wheat,
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https://en.wikipedia.org/wiki/Projective%20connection
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In differential geometry, a projective connection is a type of Cartan connection on a differentiable manifold.
The structure of a projective connection is modeled on the geometry of projective space, rather than the affine space corresponding to an affine connection. Much like affine connections, projective connections also define geodesics. However, these geodesics are not affinely parametrized. Rather they are projectively parametrized, meaning that their preferred class of parameterizations is acted upon by the group of fractional linear transformations.
Like an affine connection, projective connections have associated torsion and curvature.
Projective space as the model geometry
The first step in defining any Cartan connection is to consider the flat case: in which the connection corresponds to the Maurer-Cartan form on a homogeneous space.
In the projective setting, the underlying manifold of the homogeneous space is the projective space RPn which we shall represent by homogeneous coordinates . The symmetry group of is G = PSL(n+1,R). Let H be the isotropy group of the point . Thus, M = G/H presents as a homogeneous space.
Let be the Lie algebra of G, and that of H. Note that . As matrices relative to the homogeneous basis, consists of trace-free matrices:
.
And consists of all these matrices with . Relative to the matrix representation above, the Maurer-Cartan form of G is a system of 1-forms satisfying the structural equations (written using the Einstein summation convention):
Projective structures on manifolds
A projective structure is a linear geometry on a manifold in which two nearby points are connected by a line (i.e., an unparametrized geodesic) in a unique manner. Furthermore, an infinitesimal neighborhood of each point is equipped with a class of projective frames. According to Cartan (1924),
Une variété (ou espace) à connexion projective est une variété numérique qui, au voisinage immédiat de chaque point, présente tous les car
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https://en.wikipedia.org/wiki/Bond%20albedo
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The Bond albedo (also called spheric albedo, planetary albedo, and bolometric albedo), named after the American astronomer George Phillips Bond (1825–1865), who originally proposed it, is the fraction of power in the total electromagnetic radiation incident on an astronomical body that is scattered back out into space.
Because the Bond albedo accounts for all of the light scattered from a body at all wavelengths and all phase angles, it is a necessary quantity for determining how much energy a body absorbs. This, in turn, is crucial for determining the equilibrium temperature of a body.
Because bodies in the outer Solar System are always observed at very low phase angles from the Earth, the only reliable data for measuring their Bond albedo comes from spacecraft.
Phase integral
The Bond albedo (A) is related to the geometric albedo (p) by the expression
where q is termed the phase integral and is given in terms of the directional scattered flux I(α) into phase angle α (averaged over all wavelengths and azimuthal angles) as
The phase angle α is the angle between the source of the radiation (usually the Sun) and the observing direction, and varies from zero for light scattered back towards the source, to 180° for observations looking towards the source. For example, during opposition or looking at the full moon, α is very small, while backlit objects or the new moon have α close to 180°.
Examples
The Bond albedo is a value strictly between 0 and 1, as it includes all possible scattered light (but not radiation from the body itself). This is in contrast to other definitions of albedo such as the geometric albedo, which can be above 1. In general, though, the Bond albedo may be greater or smaller than the geometric albedo, depending on the surface and atmospheric properties of the body in question.
Some examples:
See also
Albedo
Geometric albedo
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https://en.wikipedia.org/wiki/Large%20Volume%20Detector
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The Large Volume Detector (LVD) is a particle physics experiment situated in the Gran Sasso laboratory in Italy and is operated by the Italian Institute of Nuclear Physics (INFN). It has been in operation since June 1992, and is a member of the Supernova Early Warning System. Among other work, the detector should be able to detect neutrinos from our galaxy and possibly nearby galaxies. The LVD uses 840 scintillator counters around a large tank of hydrocarbons. The detector can detect both charged current and neutral current interactions.
In 2012, they published the results of measurements of the speed of CERN Neutrinos to Gran Sasso. The results were consistent with the speed of light. See measurements of neutrino speed.
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https://en.wikipedia.org/wiki/Rabi%20frequency
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The Rabi frequency is the frequency at which the probability amplitudes of two atomic energy levels fluctuate in an oscillating electromagnetic field. It is proportional to the Transition Dipole Moment of the two levels and to the amplitude (not intensity) of the Electromagnetic field. Population transfer between the levels of such a 2-level system illuminated with light exactly resonant with the difference in energy between the two levels will occur at the Rabi frequency; when the incident light is detuned from this energy difference (detuned from resonance) then the population transfer occurs at the generalized Rabi frequency. The Rabi frequency is a semiclassical concept since it treats the atom as an object with quantized energy levels and the electromagnetic field as a continuous wave.
In the context of a nuclear magnetic resonance experiment, the Rabi frequency is the nutation frequency of a sample's net nuclear magnetization vector about a radio-frequency field. (Note that this is distinct from the Larmor frequency, which characterizes the precession of a transverse nuclear magnetization about a static magnetic field.)
Derivation
Consider two energy eigenstates of a quantum system with Hamiltonian (for example, this could be the Hamiltonian of a particle in a potential, like the Hydrogen atom or the Alkali atoms):
We want to consider the time dependent Hamiltonian
where is the potential of the electromagnetic field. Treating the potential as a perturbation, we can expect the eigenstates of the perturbed Hamiltonian to be some mixture of the eigenstates of the original Hamiltonian with time dependent coefficients:
Plugging this into the time dependent Schrödinger equation
taking the inner product with each of and , and using the orthogonality condition of eigenstates , we arrive at two equations in the coefficients and :
where . The two terms in parentheses are dipole matrix elements dotted into the polarization vector of the electromagnetic fi
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https://en.wikipedia.org/wiki/Trace%20amine-associated%20receptor
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Trace amine-associated receptors (TAARs), sometimes referred to as trace amine receptors (TAs or TARs), are a class of G protein-coupled receptors that were discovered in 2001. TAAR1, the first of six functional human TAARs, has gained considerable interest in academic and proprietary pharmaceutical research due to its role as the endogenous receptor for the trace amines phenylethylamine, tyramine, and tryptamine – metabolic derivatives of the amino acids phenylalanine, tyrosine and tryptophan, respectively – ephedrine, as well as the synthetic psychostimulants, amphetamine, methamphetamine and methylenedioxymethamphetamine (MDMA, ecstasy). In 2004, it was shown that mammalian TAAR1 is also a receptor for thyronamines, decarboxylated and deiodinated relatives of thyroid hormones. TAAR2–TAAR9 function as olfactory receptors for volatile amine odorants in vertebrates.
Animal TAAR complement
The following is a list of the TAARs contained in selected animal genomes:
Human – 6 genes (TAAR1, TAAR2, TAAR5, TAAR6, TAAR8, TAAR9) and 3 pseudogenes (TAAR3, , )
Chimpanzee – 3 genes and 6 pseudogenes
Mouse – 15 genes and 1 pseudogene
Rat – 17 genes and 2 pseudogenes
Zebrafish – 112 genes and 4 pseudogenes
Frog – 3 genes and 0 pseudogenes
Medaka – 25 genes and 1 pseudogenes
Stickleback – 25 genes and 1 pseudogenes
Human trace amine-associated receptors
Six human trace amine-associated receptors (hTAARs) – hTAAR1, hTAAR2, hTAAR5, hTAAR6, hTAAR8, and hTAAR9 – have been identified and partially characterized. The table below contains summary information from literature reviews, pharmacology databases, and supplementary primary research articles on the expression profiles, signal transduction mechanisms, ligands, and physiological functions of these receptors.
Disease links and clinical significance
Ulotaront / SEP 363856 is a TAAR1 agonist in phase 3 clinical trials for schizophrenia and earlier trials for Parkinson's Disease psychosis. The medicine has obtained Brea
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https://en.wikipedia.org/wiki/Projected%20dynamical%20system
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Projected dynamical systems is a mathematical theory investigating the behaviour of dynamical systems where solutions are restricted to a constraint set. The discipline shares connections to and applications with both the static world of optimization and equilibrium problems and the dynamical world of ordinary differential equations. A projected dynamical system is given by the flow to the projected differential equation
where K is our constraint set. Differential equations of this form are notable for having a discontinuous vector field.
History of projected dynamical systems
Projected dynamical systems have evolved out of the desire to dynamically model the behaviour of nonstatic solutions in equilibrium problems over some parameter, typically take to be time. This dynamics differs from that of ordinary differential equations in that solutions are still restricted to whatever constraint set the underlying equilibrium problem was working on, e.g. nonnegativity of investments in financial modeling, convex polyhedral sets in operations research, etc. One particularly important class of equilibrium problems which has aided in the rise of projected dynamical systems has been that of variational inequalities.
The formalization of projected dynamical systems began in the 1990s. However, similar concepts can be found in the mathematical literature which predate this, especially in connection with variational inequalities and differential inclusions.
Projections and Cones
Any solution to our projected differential equation must remain inside of our constraint set K for all time. This desired result is achieved through the use of projection operators and two particular important classes of convex cones. Here we take K to be a closed, convex subset of some Hilbert space X.
The normal cone to the set K at the point x in K is given by
The tangent cone (or contingent cone) to the set K at the point x is given by
The projection operator (or closest element mapping) of
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https://en.wikipedia.org/wiki/Download%20Cache
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The Download Cache, or downloaded files cache, is a component of Microsoft's .NET Framework that is similar to the Global Assembly Cache except that it caches assemblies that have been downloaded from the Internet.
Q.
Assemblies are downloaded from the Internet when a specific managed object is requested using the <object> tag in a web page. For example, the following HTML will cause Internet Explorer to download MyAssembly.dll to the Download Cache and will subsequently instantiate MyControl on the page that contains it.
<object id="myControlId" classid="http://MyServer/MyVirtualFolder/MyAssembly.dll#MyNamespace.MyControl">
<param name="MyProperty" value="SomeStringValue" />
</object>
Usage
Like the GAC, the Download Cache can be accessed with gacutil.exe.
One can list the contents of the Download Cache using the command:
gacutil.exe /ldl
One can delete the contents of the Download Cache using the command:
gacutil.exe /cdl
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https://en.wikipedia.org/wiki/Harmonic%20mixer
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The harmonic mixer and subharmonic mixer are a type of frequency mixer, which is a circuit that changes one signal frequency to another. The ordinary mixer has two input signals and one output signal. If the two input signals are sinewaves at frequencies f1 and f2, then the output signal consists of frequency components at the sum f1+f2 and difference f1−f2 frequencies. In contrast, the harmonic and subharmonic mixers form sum and difference frequencies at a harmonic multiple of one of the inputs. The output signal then contains frequencies such as f1+kf2 and f1−kf2 where k is an integer.
Background
The classic frequency mixer is a multiplier. Multiplying two sinewaves produces just the sum and difference frequencies; the input frequencies are suppressed, and, in theory, there are no other heterodyne products. In practice, the multiplier is not perfect, and the input frequencies and other heterodyne products will be present.
An actual multiplier is not needed. The significant requirement is a nonlinearity, and at microwave frequencies it is easier to use a nonlinearity rather than an ideal multiplier. A Taylor series expansion of a nonlinearity will show multiplications that give rise to the desired higher order products.
Design goals for mixers seek to select the desired heterodyne products and suppress the undesired ones.
Diode mixers.
Overdriven diode bridge mixers. Drive signal looks like odd harmonic waveform (essentially a square wave).
Harmonic mixer
One classic design for a harmonic mixer uses a step recovery diode (SRD). The mixer's subharmonic input is first amplified to a power level that might be around 1 watt. That signal then drives a step recovery diode impulse generator circuit that turns the sine wave into something approximating an impulse train. The resulting impulse train has the harmonics of the input sine wave present to a high frequency (such as 18 GHz). The impulse train can then be used with a diode mixer (also called a sampler).
The
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https://en.wikipedia.org/wiki/Copyright%20alternatives
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Various copyright alternatives in an alternative compensation systems (ACS) have been proposed as ways to allow the widespread reproduction of digital copyrighted works while still paying the authors and copyright owners of those works. This article only discusses those proposals which involve some form of government intervention. Other models, such as the street performer protocol or voluntary collective licenses, could arguably be called "alternative compensation systems" although they are very different and generally less effective at solving the free rider problem.
The impetus for these proposals has come from the widespread use of peer-to-peer file sharing networks. A few authors argue that an ACS is simply the only practical response to the situation. But most ACS advocates go further, holding that P2P file sharing is in fact greatly beneficial, and that tax or levy funded systems are actually more desirable tools for paying artists
than sales coupled with DRM copy prevention technologies.
Artistic freedom voucher
The artistic freedom voucher (AFV) proposal argues that the current copyright system providing a state enforced monopoly leads to "enormous inefficiencies and creates substantial enforcement problems". Under the AFV proposed system, individuals would be allowed to contribute a refundable tax credit of approximately $100 to a "creative worker", this contribution would act as a voucher that can only be used to support artistic or creative work.
Recipients of the AFV contribution would in turn be required to register with the government in similar fashion to that of religious or charitable institutions do so for tax-exempt status. The sole purpose of the registration would be to prevent fraud and would have no evaluation of the quality or work being produced. Alongside registration, artists would also now be ineligible for copyright protection for a set period of time (5 years for example) as the work is contributed to the public domain and allowed
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https://en.wikipedia.org/wiki/Biological%20system
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A biological system is a complex network which connects several biologically relevant entities. Biological organization spans several scales and are determined based different structures depending on what the system is. Examples of biological systems at the macro scale are populations of organisms. On the organ and tissue scale in mammals and other animals, examples include the circulatory system, the respiratory system, and the nervous system. On the micro to the nanoscopic scale, examples of biological systems are cells, organelles, macromolecular complexes and regulatory pathways. A biological system is not to be confused with a living system, such as a living organism.
Organ and tissue systems
These specific systems are widely studied in human anatomy and are also present in many other animals.
Respiratory system: the organs used for breathing, the pharynx, larynx, bronchi, lungs and diaphragm.
Digestive system: digestion and processing food with salivary glands, oesophagus, stomach, liver, gallbladder, pancreas, intestines, rectum and anus.
Cardiovascular system (heart and circulatory system): pumping and channeling blood to and from the body and lungs with heart, blood and blood vessels.
Urinary system: kidneys, ureters, bladder and urethra involved in fluid balance, electrolyte balance and excretion of urine.
Integumentary system: skin, hair, fat, and nails.
Skeletal system: structural support and protection with bones, cartilage, ligaments and tendons.
Endocrine system: communication within the body using hormones made by endocrine glands such as the hypothalamus, pituitary gland, pineal body or pineal gland, thyroid, parathyroid and adrenals, i.e., adrenal glands.
Lymphatic system: structures involved in the transfer of lymph between tissues and the blood stream; includes the lymph and the nodes and vessels. The lymphatic system includes functions including immune responses and development of antibodies.
Immune system: protects the organism from
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https://en.wikipedia.org/wiki/Mitointeractome
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Mitointeractome is a mitochondrial protein interactome database.
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https://en.wikipedia.org/wiki/Quasiconvex%20function
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In mathematics, a quasiconvex function is a real-valued function defined on an interval or on a convex subset of a real vector space such that the inverse image of any set of the form is a convex set. For a function of a single variable, along any stretch of the curve the highest point is one of the endpoints. The negative of a quasiconvex function is said to be quasiconcave.
All convex functions are also quasiconvex, but not all quasiconvex functions are convex, so quasiconvexity is a generalization of convexity. Univariate unimodal functions are quasiconvex or quasiconcave, however this is not necessarily the case for functions with multiple arguments. For example, the 2-dimensional Rosenbrock function is unimodal but not quasiconvex and functions with star-convex sublevel sets can be unimodal without being quasiconvex.
Definition and properties
A function defined on a convex subset of a real vector space is quasiconvex if for all and we have
In words, if is such that it is always true that a point directly between two other points does not give a higher value of the function than both of the other points do, then is quasiconvex. Note that the points and , and the point directly between them, can be points on a line or more generally points in n-dimensional space.
An alternative way (see introduction) of defining a quasi-convex function is to require that each sublevel set
is a convex set.
If furthermore
for all and , then is strictly quasiconvex. That is, strict quasiconvexity requires that a point directly between two other points must give a lower value of the function than one of the other points does.
A quasiconcave function is a function whose negative is quasiconvex, and a strictly quasiconcave function is a function whose negative is strictly quasiconvex. Equivalently a function is quasiconcave if
and strictly quasiconcave if
A (strictly) quasiconvex function has (strictly) convex lower contour sets, while a (strictly) qu
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https://en.wikipedia.org/wiki/Sociality
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Sociality is the degree to which individuals in an animal population tend to associate in social groups (gregariousness) and form cooperative societies.
Sociality is a survival response to evolutionary pressures. For example, when a mother wasp stays near her larvae in the nest, parasites are less likely to eat the larvae. Biologists suspect that pressures from parasites and other predators selected this behavior in wasps of the family Vespidae.
This wasp behaviour evidences the most fundamental characteristic of animal sociality: parental investment. Parental investment is any expenditure of resources (time, energy, social capital) to benefit one's offspring. Parental investment detracts from a parent's capacity to invest in future reproduction and aid to kin (including other offspring). An animal that cares for its young but shows no other sociality traits is said to be subsocial.
An animal that exhibits a high degree of sociality is called a social animal. The highest degree of sociality recognized by sociobiologists is eusociality. A eusocial taxon is one that exhibits overlapping adult generations, reproductive division of labor, cooperative care of young, and—in the most refined cases—a biological caste system.
Presociality
Solitary animals such as the jaguar do not associate except for courtship and mating. If an animal taxon shows a degree of sociality beyond courtship and mating, but lacks any of the characteristics of eusociality, it is said to be presocial. Although presocial species are much more common than eusocial species, eusocial species have disproportionately large populations.
The entomologist Charles D. Michener published a classification system for presociality in 1969, building on the earlier work of Suzanne Batra (who coined the words eusocial and quasisocial in 1966). Michener used these terms in his study of bees, but also saw a need for additional classifications: subsocial, communal, and semisocial. In his use of these words, he did
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https://en.wikipedia.org/wiki/API-Calculus
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API Calculus is a program that solves calculus problems using operating systems within a device that solves calculus problems. In 1989, the PI- Calculus was created by Robin Milner and was very successful throughout the years. The PI Calculus is an extension of the process algebra CCS, a tool that has algebraic languages that are specific to processing and formulating statements. The PI Calculus provides a formal theory for modeling systems and reasoning about their behaviors. In the PI Calculus there are two specific variables such as name and processes. But it was not until 2002 when Shahram Rahimi decided to create an upgraded version of the PI- Calculus and call it the API Calculus. Milner claimed the detailed characteristics of the API Calculus to be its "Communication Ability, Capacity for Cooperation, Capacity for Reasoning and Learning, Adaptive Behavior and Trustworthiness." The main purpose of creating this mobile advancement is to better network and communicate with other operators while completing a task. Unfortunately, the API Calculus is not perfect and has faced a problem with its security system. The language has seven features that was created within the device that the PI Calculus does not have. Since this program is so advanced by the way the software was created and the different abilities that are offered in the program, it is required to be converted to other programming languages so it can be used on various devices and other computing languages. Although the API Calculus is currently being used by various other programming languages, modifications are still being done since the security on the API Calculus is causing problems to users.
What Does It Do?
The API Calculus is the main demonstration for modeling migration, intelligence, natural grouping and security in agent-based systems. This calculus programming language is usually used in various other program languages such as Java. In Java, a famous programming language used by variou
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https://en.wikipedia.org/wiki/1%3A24%20scale
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1:24 scale is a size for automobile models such as injection-molded plastic model kits or metal die-cast toys, which are built and collected by both children and adults. 1:24 means that a unit of measurement, such as one inch or one centimeter, on the model represents 24 units on the actual object. An example would be one inch of length on a model automobile would represent 24 inches on an actual vehicle. Primarily automobile models are made on this scale, with a few examples of tractor-trailers and other larger equipment. In the United States, there is a minor variation of the 1:24 scale, where many automobile plastic model kits are scaled at 1:25.
1:24 is the largest of the traditional slot car sizes - and the earliest. Lionel's (USA) 1:24 electric autos of 1912-1916 became the first known commercial slot cars. In 1955, the Model Automobile Racing Association of Kalamazoo, Michigan, built the first track for electric rail-racing (the short-lived immediate predecessor to slot racing) in the US. Unlike the seminal Southport (UK) track that inspired it, the MARA table was designed for 1:24 as well as 1:32 competition. With that beginning, the US adopted 1:24 as the primary scale for serious competition during the heyday of slot car racing in the 1960s, while Britain and Europe favored 1:32 and have continued to do so.
1:24 scale is very close to the scale (1:22.5) used for European G scale narrow-gauge model trains, so 1:24 models are often used on model train layouts. Doll houses and furniture are also found on a 1:24 scale. An average adult male human figure stands just under tall.
The British plastic model kit company Airfix has produced several 1:24 scale aircraft in its 'Super Kit' range, including the Supermarine Spitfire, Messerschmitt Bf 109 - both initially with the option of motorised propellers, Junkers Ju 87 Stuka, Hawker Siddeley Harrier, and Focke-Wulf Fw 190. The last to be released were the de Havilland Mosquito and the Hawker Typhoon. An earlier
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https://en.wikipedia.org/wiki/Self-averaging
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A self-averaging physical property of a disordered system is one that can be described by averaging over a sufficiently large sample. The concept was introduced by Ilya Mikhailovich Lifshitz.
Definition
Frequently in physics one comes across situations where quenched randomness plays an important role. Any physical property X of such a system, would require an averaging over all disorder realisations. The system can be completely described by the average [X] where [...] denotes averaging over realisations (“averaging over samples”) provided the relative variance RX = VX / [X]2 → 0 as N→∞, where VX = [X2] − [X]2 and N denotes the size of the realisation. In such a scenario a single large system is sufficient to represent the whole ensemble. Such quantities are called self-averaging. Away from criticality, when the larger lattice is built from smaller blocks, then due to the additivity property of an extensive quantity, the central limit theorem guarantees that RX ~ N−1 thereby ensuring self-averaging. On the other hand, at the critical point, the question whether is self-averaging or not becomes nontrivial, due to long range correlations.
Non self-averaging systems
At the pure critical point randomness is classified as relevant if, by the standard definition of relevance, it leads to a change in the critical behaviour (i.e., the critical exponents) of the pure system. It has been shown by recent renormalization group and numerical studies that self-averaging property is lost if randomness or disorder is relevant. Most importantly as N → ∞, RX at the critical point approaches a constant. Such systems are called non self-averaging. Thus unlike the self-averaging scenario, numerical simulations cannot lead to an improved picture in larger lattices (large N), even if the critical point is exactly known. In summary, various types of self-averaging can be indexed with the help of the asymptotic size dependence of a quantity like RX. If RX falls off to zero wi
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https://en.wikipedia.org/wiki/Fractional%20crystallization%20%28chemistry%29
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In chemistry, fractional crystallization is a method of refining substances based on differences in their solubility. It fractionates via differences in crystallization (forming of crystals). If a mixture of two or more substances in solution are allowed to crystallize, for example by allowing the temperature of the solution to decrease or increase, the precipitate will contain more of the least soluble substance. The proportion of components in the precipitate will depend on their solubility products. If the solubility products are very similar, a cascade process will be needed to effectuate a complete separation.
This technique is often used in chemical engineering to obtain pure substances, or to recover saleable products from waste solutions.
Fractional crystallization can be used to separate solid-solid mixtures. An example of this is separating KNO3 and KClO3.
See also
Cold Water Extraction
Fractional crystallization (geology)
Fractional freezing
Laser-heated pedestal growth
Pumpable ice technology
Recrystallization (chemistry)
Seed crystal
Single crystal
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https://en.wikipedia.org/wiki/List%20of%20formulas%20in%20Riemannian%20geometry
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This is a list of formulas encountered in Riemannian geometry. Einstein notation is used throughout this article. This article uses the "analyst's" sign convention for Laplacians, except when noted otherwise.
Christoffel symbols, covariant derivative
In a smooth coordinate chart, the Christoffel symbols of the first kind are given by
and the Christoffel symbols of the second kind by
Here is the inverse matrix to the metric tensor . In other words,
and thus
is the dimension of the manifold.
Christoffel symbols satisfy the symmetry relations
or, respectively, ,
the second of which is equivalent to the torsion-freeness of the Levi-Civita connection.
The contracting relations on the Christoffel symbols are given by
and
where |g| is the absolute value of the determinant of the metric tensor . These are useful when dealing with divergences and Laplacians (see below).
The covariant derivative of a vector field with components is given by:
and similarly the covariant derivative of a -tensor field with components is given by:
For a -tensor field with components this becomes
and likewise for tensors with more indices.
The covariant derivative of a function (scalar) is just its usual differential:
Because the Levi-Civita connection is metric-compatible, the covariant derivatives of metrics vanish,
as well as the covariant derivatives of the metric's determinant (and volume element)
The geodesic starting at the origin with initial speed has Taylor expansion in the chart:
Curvature tensors
Definitions
(3,1) Riemann curvature tensor
(3,1) Riemann curvature tensor
Ricci curvature
Scalar curvature
Traceless Ricci tensor
(4,0) Riemann curvature tensor
(4,0) Weyl tensor
Einstein tensor
Identities
Basic symmetries
The Weyl tensor has the same basic symmetries as the Riemann tensor, but its 'analogue' of the Ricci tensor is zero:
The Ricci tensor, the Einstein tensor, and the traceless Ricci tensor are symmetric 2-tensors:
First Bianch
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https://en.wikipedia.org/wiki/Ambient%20construction
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In conformal geometry, the ambient construction refers to a construction of Charles Fefferman and Robin Graham for which a conformal manifold of dimension n is realized (ambiently) as the boundary of a certain Poincaré manifold, or alternatively as the celestial sphere of a certain pseudo-Riemannian manifold.
The ambient construction is canonical in the sense that it is performed only using the conformal class of the metric: it is conformally invariant. However, the construction only works asymptotically, up to a certain order of approximation. There is, in general, an obstruction to continuing this extension past the critical order. The obstruction itself is of tensorial character, and is known as the (conformal) obstruction tensor. It is, along with the Weyl tensor, one of the two primitive invariants in conformal differential geometry.
Aside from the obstruction tensor, the ambient construction can be used to define a class of conformally invariant differential operators known as the GJMS operators.
A related construction is the tractor bundle.
Overview
The model flat geometry for the ambient construction is the future null cone in Minkowski space, with the origin deleted. The celestial sphere at infinity is the conformal manifold M, and the null rays in the cone determine a line bundle over M. Moreover, the null cone carries a metric which degenerates in the direction of the generators of the cone.
The ambient construction in this flat model space then asks: if one is provided with such a line bundle, along with its degenerate metric, to what extent is it possible to extend the metric off the null cone in a canonical way, thus recovering the ambient Minkowski space? In formal terms, the degenerate metric supplies a Dirichlet boundary condition for the extension problem and, as it happens, the natural condition is for the extended metric to be Ricci flat (because of the normalization of the normal conformal connection.)
The ambient construction gener
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https://en.wikipedia.org/wiki/Bach%20tensor
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In differential geometry and general relativity, the Bach tensor is a trace-free tensor of rank 2 which is conformally invariant in dimension . Before 1968, it was the only known conformally invariant tensor that is algebraically independent of the Weyl tensor. In abstract indices the Bach tensor is given by
where is the Weyl tensor, and the Schouten tensor given in terms of the Ricci tensor and scalar curvature by
See also
Cotton tensor
Obstruction tensor
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https://en.wikipedia.org/wiki/Casein%20kinase%201
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The Casein kinase 1 family () of protein kinases are serine/threonine-selective enzymes that function as regulators of signal transduction pathways in most eukaryotic cell types. CK1 isoforms are involved in Wnt signaling, circadian rhythms, nucleo-cytoplasmic shuttling of transcription factors, DNA repair, and DNA transcription.
Discovery
By the early 1950s it was known from metabolic labeling studies using radioactive phosphate that phosphate groups attached to phosphoproteins inside cells can sometimes undergo rapid exchange of new phosphate for old. In order to perform experiments that would allow isolation and characterization of the enzymes involved in attaching and removing phosphate from proteins, there was a need for convenient substrates for protein kinases and protein phosphatases. Casein has been used as a substrate since the earliest days of research on protein phosphorylation. By the late 1960s, cyclic AMP-dependent protein kinase had been purified, and most attention was centered on kinases and phosphatases that could regulate the activity of important enzymes. Casein kinase activity associated with the endoplasmic reticulum of mammary glands was first characterized in 1974, and its activity was shown to not depend on cyclic AMP.
CK1 family
The CK1 family of monomeric serine–threonine protein kinases is found in eukaryotic organisms from yeast to humans. Mammals have seven family members (sometimes referred to as isoforms, but encoded by distinct genes): alpha, beta 1, gamma 1, gamma 2, gamma 3, delta, and epsilon. Isoforms range from 22 to 55 kDa and have been identified in the membranes, nucleus, and cytoplasm of eukaryotes and additionally in the mitotic spindle in mammalian cells. The family members have the highest homology in their kinase domains (53%–98% identical) and differ from most other protein kinases by the presence of the sequence S-I-N instead of A-P-E in kinase domain VIII. The family members appear to have similar substrate specif
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https://en.wikipedia.org/wiki/Landau%27s%20problems
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At the 1912 International Congress of Mathematicians, Edmund Landau listed four basic problems about prime numbers. These problems were characterised in his speech as "unattackable at the present state of mathematics" and are now known as Landau's problems. They are as follows:
Goldbach's conjecture: Can every even integer greater than 2 be written as the sum of two primes?
Twin prime conjecture: Are there infinitely many primes p such that p + 2 is prime?
Legendre's conjecture: Does there always exist at least one prime between consecutive perfect squares?
Are there infinitely many primes p such that p − 1 is a perfect square? In other words: Are there infinitely many primes of the form n2 + 1?
, all four problems are unresolved.
Progress toward solutions
Goldbach's conjecture
Goldbach's weak conjecture, every odd number greater than 5 can be expressed as the sum of three primes, is a consequence of Goldbach's conjecture. Ivan Vinogradov proved it for large enough n (Vinogradov's theorem) in 1937, and Harald Helfgott extended this to a full proof of Goldbach's weak conjecture in 2013.
Chen's theorem, another weakening of Goldbach's conjecture, proves that for all sufficiently large n, where p is prime and q is either prime or semiprime. Bordignon, Johnston, and Starichkova, correcting and improving on Yamada, proved an explicit version of Chen's theorem: every even number greater than is the sum of a prime and a product of at most two primes. Bordignon & Starichkova reduce this to assuming the Generalized Riemann hypothesis for Dirichlet L-functions. Johnson and Starichkova give a version working for all n >= 4 at the cost of using a number which is the product of at most 369 primes rather than a prime or semiprime; under GRH they improve 369 to 33.
Montgomery and Vaughan showed that the exceptional set of even numbers not expressible as the sum of two primes was of density zero, although the set is not proven to be finite. The best current bounds on th
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https://en.wikipedia.org/wiki/Acoustic%20wave
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Acoustic waves are a type of energy propagation through a medium by means of adiabatic loading and unloading. Important quantities for describing acoustic waves are acoustic pressure, particle velocity, particle displacement and acoustic intensity. Acoustic waves travel with a characteristic acoustic velocity that depends on the medium they're passing through. Some examples of acoustic waves are audible sound from a speaker (waves traveling through air at the speed of sound), seismic waves (ground vibrations traveling through the earth), or ultrasound used for medical imaging (waves traveling through the body).
Wave properties
Acoustic wave is a mechanical wave that transmits energy through the movements of atoms and molecules. Acoustic wave transmits through liquids in longitudinal manner (movement of particles are parallel to the direction of propagation of the wave); in contrast to electromagnetic wave that transmits in transverse manner (movement of particles at a right angle to the direction of propagation of the wave). However, in solids, acoustic wave transmits in both longitudinal and transverse manners due to presence of shear moduli in such a state of matter.
Acoustic wave equation
The acoustic wave equation describes the propagation of sound waves. The acoustic wave equation for sound pressure in one dimension is given by
where
is sound pressure in Pa
is position in the direction of propagation of the wave, in m
is speed of sound in m/s
is time in s
The wave equation for particle velocity has the same shape and is given by
where
is particle velocity in m/s
For lossy media, more intricate models need to be applied in order to take into account frequency-dependent attenuation and phase speed. Such models include acoustic wave equations that incorporate fractional derivative terms, see also the acoustic attenuation article.
D'Alembert gave the general solution for the lossless wave equation. For sound pressure, a solution would be
where
is angu
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https://en.wikipedia.org/wiki/List%20of%20Plan%209%20applications
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This is a list of Plan 9 programs. Many of these programs are very similar to the UNIX programs with the same name, others are to be found only on Plan 9. Others again share only the name, but have a different behaviour.
System software
General user
dd – convert and copy a file
date – date and time
echo – print arguments
file – determine file type
ns – display namespace
plumb – send message to plumber
plumber – interprocess messaging
rc – rc is the Plan 9 shell
rio – the new Plan 9 windowing system
8½ – the old Plan 9 windowing system
uptime – show how long the system has been running
System management
Processes and tasks management
time – time a command
kill, slay, broke – print commands to kill processes
sleep – suspend execution for an interval
ps – process status
psu – process status information about processes started by a specific user
User management and support
passwd, netkey, iam – change user password
who – who is using the machine
man, lookman – print or find pages of this manual
File system and server
/boot/boot – connect to the root file server
fossil/fossil, fossil/flchk, fossil/flfmt, fossil/conf, fossil/last – archival file server
history – print file names from the dump
users – file server user list format
vac – create a vac archive on Venti
venti/buildindex, venti/checkarenas, venti/checkindex, venti/conf, venti/copy, venti/fmtarenas, venti/fmtindex, venti/fmtisect, venti/rdarena, venti/rdarenablocks, venti/read, venti/wrarenablocks, venti/write – Venti maintenance and debugging commands
venti/venti, venti/sync – an archival block storage server
yesterday, diffy – print file names from the dump
Hardware devices
setrtc – set real time clock (RTC) on PC hardware
Files and text
Filesystem utilities
chgrp – change file group
chmod – change mode
cp, fcp, mv – copy, move files
du – disk usage
ls, lc – list contents of directory
mkdir – make a directory
bind, mount, umount – change name space
pwd, pbd –
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https://en.wikipedia.org/wiki/Larvicide
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A larvicide (alternatively larvacide) is an insecticide that is specifically targeted against the larval life stage of an insect. Their most common use is against mosquitoes. Larvicides may be contact poisons, stomach poisons, growth regulators, or (increasingly) biological control agents.
Biological agents
The biological control agent Bacillus thuringiensis, also known as Bt, is a bacterial disease specific to Lepidopteran caterpillars. Bacillus thuringiensis israelensis, also known as Bti, and Bacillus sphaericus, which affect larval mosquitoes and some midges, have come into increasing use in recent times.
Bti and B. sphaericus are both naturally occurring soil bacterium registered as larvicides under the names Bactivec, Bacticide, Aquabac, Teknar, Vectobac, LarvX, and VectoLex CG. Typically in granular form, pellets are distributed on the surface of stagnant water locations. When the mosquito larvae ingest the bacteria, crystallized toxins are produced that destroy the digestive tract, resulting in death. These larvicides will last only a few weeks in water and pose no danger to humans, non-targeted animal species, or the environment when used according to directions.
Chemical Agents
Methoprene is an insect growth regulator agent that interrupts the growth cycle of insect larvae, preventing them from development beyond the pupa stage. MetaLarv and Altosid are products containing S-methoprene as the active ingredient. They are usually applied to larger bodies of water in the form of time-release formulations that can last from one to five months. Use of this larvicide does not pose an unreasonable health risks to humans or other wildlife and it will not leach into the ground water supply. Methoprene is moderately toxic to some fish, shrimp, lobster, and crayfish, and highly toxic to some fish and freshwater invertebrates; it bioaccumulates in fish tissues.
Temephos, marketed as Abate and ProVect, is an organophosphate which prevents mosquito larvae from d
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https://en.wikipedia.org/wiki/Rothe%E2%80%93Hagen%20identity
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In mathematics, the Rothe–Hagen identity is a mathematical identity valid for all complex numbers () except where its denominators vanish:
It is a generalization of Vandermonde's identity, and is named after Heinrich August Rothe and Johann Georg Hagen.
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https://en.wikipedia.org/wiki/Lerche%E2%80%93Newberger%20sum%20rule
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The Lerche–Newberger, or Newberger, sum rule, discovered by B. S. Newberger in 1982, finds the sum of certain infinite series involving Bessel functions Jα of the first kind.
It states that if μ is any non-integer complex number, , and Re(α + β) > −1, then
Newberger's formula generalizes a formula of this type proven by Lerche in 1966; Newberger discovered it independently. Lerche's formula has γ =1; both extend a standard rule for the summation of Bessel functions, and are useful in plasma physics.
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https://en.wikipedia.org/wiki/Time%20geography
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Time geography or time-space geography is an evolving transdisciplinary perspective on spatial and temporal processes and events such as social interaction, ecological interaction, social and environmental change, and biographies of individuals. Time geography "is not a subject area per se", but rather an integrative ontological framework and visual language in which space and time are basic dimensions of analysis of dynamic processes. Time geography was originally developed by human geographers, but today it is applied in multiple fields related to transportation, regional planning, geography, anthropology, time-use research, ecology, environmental science, and public health. According to Swedish geographer Bo Lenntorp: "It is a basic approach, and every researcher can connect it to theoretical considerations in her or his own way."
Origins
The Swedish geographer Torsten Hägerstrand created time geography in the mid-1960s based on ideas he had developed during his earlier empirical research on human migration patterns in Sweden. He sought "some way of finding out the workings of large socio-environmental mechanisms" using "a physical approach involving the study of how events occur in a time-space framework". Hägerstrand was inspired in part by conceptual advances in spacetime physics and by the philosophy of physicalism.
Hägerstrand's earliest formulation of time geography informally described its key ontological features: "In time-space the individual describes a path" within a situational context; "life paths become captured within a net of constraints, some of which are imposed by physiological and physical necessities and some imposed by private and common decisions". "It would be impossible to offer a comprehensive taxonomy of constraints seen as time-space phenomena", Hägerstrand said, but he "tentatively described" three important classes of constraints:
capability constraints — limitations on the activity of individuals because of their biological struc
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https://en.wikipedia.org/wiki/Casein%20kinase%202
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Casein kinase 2 ()(CK2/CSNK2) is a serine/threonine-selective protein kinase that has been implicated in cell cycle control, DNA repair, regulation of the circadian rhythm, and other cellular processes. De-regulation of CK2 has been linked to tumorigenesis as a potential protection mechanism for mutated cells. Proper CK2 function is necessary for survival of cells as no knockout models have been successfully generated.
Structure
CK2 typically appears as a tetramer of two α subunits; α being 42 kDa and α’ being 38 kDa, and two β subunits, each weighing in at 28 kDa. The β regulatory domain only has one isoform and therefore within the tetramer will have two β subunits. The catalytic α domains appear as an α or α’ variant and can either be formed in a homodimer (α & α, or α’ & α’) formation or heterodimer formation (α & α’). It is worth noting that other β isoforms have been found in other organisms but not in humans.
The α subunits do not require the β regulatory subunits to function, this allows dimers to form of the catalytic domains independent of β subunit transcription. The presence of these α subunits does have an effect on the phosphorylation targets of CK2. A functional difference between α and α’ has been found but the exact nature of differences isn't fully understood yet. An example is that Caspase 3 is preferentially phosphorylated by α’ based tetramers over α based tetramers.
Function
CK2 is a protein kinase responsible for phosphorylation of substrates in various pathways within a cell; ATP or GTP can be used as phosphate source. CK2 has a dual functionality with involvement in cell growth/proliferation and suppression of apoptosis. CK2s anti-apoptotic function is in the continuation of the cell cycle; from G1 to S phase and G2 to M phase checkpoints. This function is achieved by protecting proteins from caspase-mediated apoptosis via phosphorylation of sites adjacent to the caspase cleavage site, blocking the activity of caspase proteins. CK2 also
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https://en.wikipedia.org/wiki/Potato%20cyst%20nematode
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Potato root nematodes or potato cyst nematodes (PCN) are 1-mm long roundworms belonging to the genus Globodera, which comprises around 12 species. They live on the roots of plants of the family Solanaceae, such as potatoes and tomatoes. PCN cause growth retardation and, at very high population densities, damage to the roots and early senescence of plants. The nematode is not indigenous to Europe but originates from the Andes. Fields are free from PCN until an introduction occurs, after which the typical patches, or hotspots, occur on the farmland. These patches can become full field infestations when unchecked. Yield reductions can average up to 60% at high population densities.
Biology and life cycle
The eggs hatch in the presence of Solanoeclepine A, a substance secreted by the roots of host plants otherwise known as root exudates. The nematodes hatch when they grow into a second-stage juvenile (J2). At this stage, the J2 nematodes find host cells to feed off of. The potato cyst nematodes are endoparasites meaning they go completely into the root to feed. Access to the root cells is gained through piercing through the cell wall using the nematode’s stylet. After a feeding tube has been established, a syncytium begins to form through the breakdown of multiple cell walls adjacent to each other. J2 nematodes continue to feed until they grow into third-stage juveniles (J3), then fourth-stage juveniles (J4), and finally reach the adult stage. The shape of the J3 females begins to appear more like a sac as the female grows into a J4 nematode. At the J4 stage, the body of the female nematode lies outside of the root while the head remains inside the cell. During this stage, the male nematodes become motile again and are then able to fertilize the female nematodes leading to embryos developing inside the female body. Once the female is fertilized, the female dies and leaves a protective cyst containing 200-500 eggs. Once the cysts detach from the original hosts, they rem
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https://en.wikipedia.org/wiki/Mechanical%20singularity
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In engineering, a mechanical singularity is a position or configuration of a mechanism or a machine where the subsequent behaviour cannot be predicted, or the forces or other physical quantities involved become infinite or nondeterministic.
When the underlying engineering equations of a mechanism or machine are evaluated at the singular configuration (if any exists), then those equations exhibit mathematical singularity.
Examples of mechanical singularities are gimbal lock and in static mechanical analysis, an under-constrained system.
Types of singularities
There are three types of singularities that can be found in mechanisms: direct-kinematics singularities, inverse-kinematics singularities, and combined singularities. These singularities occur when one or both Jacobian matrices of the mechanisms becomes singular of rank-deficient. The relationship between the input and output velocities of the mechanism are defined by the following general equation:
where is the output velocities, is the input velocities, is the direct-kinematics Jacobians, and is the inverse-kinematics Jacobian.
Type-I: Inverse-kinematics singularities
This first kind of singularities occurs when:
Type-II: Direct-kinematics singularities
This second kind of singularities occurs when:
Type-III: Combined singularities
This kind of singularities occurs when for a particular configuration, both and become singular simultaneously.
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https://en.wikipedia.org/wiki/AP%20Physics%20C%3A%20Electricity%20and%20Magnetism
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Advanced Placement (AP) Physics C: Electricity and Magnetism (also known as AP Physics C: E&M or AP E&M) is an introductory physics course administered by the College Board as part of its Advanced Placement program. It is intended to proxy a second-semester calculus-based university course in electricity and magnetism. The content of Physics C: E&M overlaps with that of AP Physics 2, but Physics 2 is algebra-based and covers other topics outside of electromagnetism, while Physics C is calculus-based and only covers electromagnetism. Physics C: E&M may be combined with its mechanics counterpart to form a year-long course that prepares for both exams.
Course content
E&M is equivalent to an introductory college course in electricity and magnetism for physics or engineering majors. The course modules are:
Electrostatics
Conductors, capacitors, and dielectrics
Electric circuits
Magnetic fields
Electromagnetism.
Methods of calculus are used wherever appropriate in formulating physical principles and in applying them to physical problems. Therefore, students should have completed or be concurrently enrolled in a calculus class.
AP test
The course culminates in an optional exam for which high-performing students may receive some credit towards their college coursework, depending on the institution.
Registration
The AP examination for AP Physics C: Electricity and Magnetism is separate from the AP examination for AP Physics C: Mechanics. Before 2006, test-takers paid only once and were given the choice of taking either one or two parts of the Physics C test.
Format
The exam is typically administered on a Monday afternoon in May. The exam is configured in two categories: a 35-question multiple choice section and a 3-question free response section. Test takers are allowed to use an approved calculator during the entire exam. The test is weighted such that each section is worth half of the final score. This and AP Physics C: Mechanics are the shortest AP exams, with
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https://en.wikipedia.org/wiki/Chebyshev%20function
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In mathematics, the Chebyshev function is either a scalarising function (Tchebycheff function) or one of two related functions. The first Chebyshev function or is given by
where denotes the natural logarithm, with the sum extending over all prime numbers that are less than or equal to .
The second Chebyshev function is defined similarly, with the sum extending over all prime powers not exceeding
where is the von Mangoldt function. The Chebyshev functions, especially the second one , are often used in proofs related to prime numbers, because it is typically simpler to work with them than with the prime-counting function, (see the exact formula below.) Both Chebyshev functions are asymptotic to , a statement equivalent to the prime number theorem.
Tchebycheff function, Chebyshev utility function, or weighted Tchebycheff scalarizing function is used when one has several functions to be minimized and one wants to "scalarize" them to a single function:
By minimizing this function for different values of , one obtains every point on a Pareto front, even in the nonconvex parts. Often the functions to be minimized are not but for some scalars . Then
All three functions are named in honour of Pafnuty Chebyshev.
Relationships
The second Chebyshev function can be seen to be related to the first by writing it as
where is the unique integer such that and . The values of are given in . A more direct relationship is given by
Note that this last sum has only a finite number of non-vanishing terms, as
The second Chebyshev function is the logarithm of the least common multiple of the integers from 1 to .
Values of for the integer variable are given at .
Relationships between and
Source:
The following theorem relates the two quotients and .
Theorem: For , we have
Note: This inequality implies that
In other words, if one of the or tends to a limit then so does the other, and the two limits are equal.
Proof: Since , we find that
But from the def
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https://en.wikipedia.org/wiki/Implicational%20propositional%20calculus
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In mathematical logic, the implicational propositional calculus is a version of classical propositional calculus which uses only one connective, called implication or conditional. In formulas, this binary operation is indicated by "implies", "if ..., then ...", "→", "", etc..
Functional (in)completeness
Implication alone is not functionally complete as a logical operator because one cannot form all other two-valued truth functions from it.
For example, the two-place truth function that always returns false is not definable from → and arbitrary sentence variables: any formula constructed from → and propositional variables must receive the value true when all of its variables are evaluated to true.
It follows that {→} is not functionally complete.
However, if one adds a nullary connective ⊥ for falsity, then one can define all other truth functions. Formulas over the resulting set of connectives {→, ⊥} are called f-implicational. If P and Q are propositions, then:
¬P is equivalent to P → ⊥
P ∧ Q is equivalent to (P → (Q → ⊥)) → ⊥
P ∨ Q is equivalent to (P → Q) → Q
P ↔ Q is equivalent to ((P → Q) → ((Q → P) → ⊥)) → ⊥
Since the above operators are known to be functionally complete, it follows that any truth function can be expressed in terms of → and ⊥.
Axiom system
The following statements are considered tautologies (irreducible and intuitively true, by definition).
Axiom schema 1 is P → (Q → P).
Axiom schema 2 is (P → (Q → R)) → ((P → Q) → (P → R)).
Axiom schema 3 (Peirce's law) is ((P → Q) → P) → P.
The one non-nullary rule of inference (modus ponens) is: from P and P → Q infer Q.
Where in each case, P, Q, and R may be replaced by any formulas which contain only "→" as a connective. If Γ is a set of formulas and A a formula, then means that A is derivable using the axioms and rules above and formulas from Γ as additional hypotheses.
Łukasiewicz (1948) found an axiom system for the implicational calculus, which replaces the schemas 1–3 above with a single schem
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https://en.wikipedia.org/wiki/Molecular%20mimicry
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Molecular mimicry is the theoretical possibility that sequence similarities between foreign and self-peptides are enough to result in the cross-activation of autoreactive T or B cells by pathogen-derived peptides. Despite the prevalence of several peptide sequences which can be both foreign and self in nature, just a few crucial residues can activate a single antibody or TCR (T cell receptor). This highlights the importance of structural homology in the theory of molecular mimicry. Upon activation, these "peptide mimic" specific T or B cells can cross-react with self-epitopes, thus leading to tissue pathology (autoimmunity). Molecular mimicry is one of several ways in which autoimmunity can be evoked. A molecular mimicking event is more than an epiphenomenon despite its low probability, and these events have serious implications in the onset of many human autoimmune disorders.
One possible cause of autoimmunity, the failure to recognize self antigens as "self", is a loss of immunological tolerance, the ability for the immune system to discriminate between self and non-self. Other possible causes include mutations governing programmed cell death or environmental products that injure target tissues, thus causing a release of immunostimulatory alarm signals. Growth in the field of autoimmunity has resulted in more frequent diagnosis of autoimmune diseases. The resulting data show that autoimmune diseases affect approximately 1 in 31 people within the general population. Growth has also led to a greater characterization of what autoimmunity is and how it can be studied and treated. With more research comes growth in the study of the several different ways in which autoimmunity can occur, one of which is molecular mimicry. The mechanism by which pathogens have similar amino acid sequences or the homologous three-dimensional crystal structure of immunodominant epitopes remains a mystery.
Immunological tolerance
Tolerance is a fundamental property of the immune system.
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https://en.wikipedia.org/wiki/Jacobi%20rotation
|
In numerical linear algebra, a Jacobi rotation is a rotation, Qkℓ, of a 2-dimensional linear subspace of an n-dimensional inner product space, chosen to zero a symmetric pair of off-diagonal entries of an n×n real symmetric matrix, A, when applied as a similarity transformation:
It is the core operation in the Jacobi eigenvalue algorithm, which is numerically stable and well-suited to implementation on parallel processors .
Only rows k and ℓ and columns k and ℓ of A will be affected, and that A will remain symmetric. Also, an explicit matrix for Qkℓ is rarely computed; instead, auxiliary values are computed and A is updated in an efficient and numerically stable way. However, for reference, we may write the matrix as
That is, Qkℓ is an identity matrix except for four entries, two on the diagonal (qkk and qℓℓ, both equal to c) and two symmetrically placed off the diagonal (qkℓ and qℓk, equal to s and −s, respectively). Here c = cos θ and s = sin θ for some angle θ; but to apply the rotation, the angle itself is not required. Using Kronecker delta notation, the matrix entries can be written:
Suppose h is an index other than k or ℓ (which must themselves be distinct). Then the similarity update produces, algebraically:
Numerically stable computation
To determine the quantities needed for the update, we must solve the off-diagonal equation for zero . This implies that:
Set β to half of this quantity:
If akℓ is zero we can stop without performing an update, thus we never divide by zero. Let t be tan θ. Then with a few trigonometric identities we reduce the equation to:
For stability we choose the solution:
From this we may obtain c and s as:
Although we now could use the algebraic update equations given previously, it may be preferable to rewrite them. Let:
so that ρ = tan(θ/2). Then the revised update equations are:
As previously remarked, we need never explicitly compute the rotation angle θ. In fact, we can rep
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https://en.wikipedia.org/wiki/International%20Social%20Survey%20Programme
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The International Social Survey Programme (ISSP) is a collaboration between different nations conducting surveys covering topics which are useful for social science research. The ISSP researchers develop questions which are meaningful and relevant to all countries which can be expressed in an equal manner in different languages. The results of the surveys provide a cross-national and cross-cultural perspective to individual national studies. By 2021, 58 countries have already taken part in the ISSP.
History
The ISSP was founded in 1984 by research organizations from four countries:
Zentrum für Umfragen, Methoden, und Analysen (ZUMA), Mannheim, Germany, now GESIS – Leibniz Institute for the Social Sciences
National Opinion Research Center (NORC), University of Chicago, Chicago, Illinois, United States.
Social and Community Planning Research (SCPR), London, United Kingdom, now National Centre for Social Research, NatCen
Research School of Social Sciences (RSSS), Australian National University, now School of Demography Canberra, Australia.
Four different Social Surveys included a common module each year:
The British Social Attitudes Survey (BSA) in the UK
The General Social Survey (GSS) in the USA
The ALLBUS or German General Social Survey (GGSS) in Germany and
The Surveys by the Research School of Social Sciences
Since then social science institutions from 58 different countries included a 15-minute supplement to their national surveys. The membership to the ISSP is institutional and by country. One or more than one institute in a country can co-operate on ISSP research (cf. France and Spain). The common module surveyed by the member institutions also contains an extensive common core of background variables. The modules focus on one specific topic each year and were planned to be repeated more or less every five to ten years. When it comes to the researchers choice of topics, the relevance of the area of social sciences in the year of the survey is taken
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https://en.wikipedia.org/wiki/Centre%20for%20DNA%20Fingerprinting%20and%20Diagnostics
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Centre for DNA Fingerprinting and Diagnostics (CDFD) is an Indian biotechnology research centre, located in Hyderabad, India, operated by the Department of Biotechnology, Ministry of Science and Technology, Government of India. CDFD is a Sun Microsystems centre of excellence in medical bio-informatics, supported with a strong bioinformatics facility, and is the India node of the EMBnet. In addition, DNA fingerprinting and diagnostics services provided by the centre support some of the activities. The centre utilises the Combined DNA Index System for DNA profile matching. The CDFD and the U.S. Federal Bureau of Investigation signed a memorandum of understanding in 2014 for the acquisition of CODIS.
CDFD receives funding from other agencies like the Wellcome Trust on specific collaborative projects. The centre is recognised by the University of Hyderabad and Manipal University for pursuing a doctor of philosophy in life sciences. Research at CDFD has focused largely on molecular epidemiology of bacterial pathogens, structural genetics, molecular genetics, bioinformatics and computational biology.
History
CDFD was conceptualised by then CCMB director Lalji Singh. It evolved into its current form of a modern institution encompassing both basic and applied research in diverse areas of modern biology under its founder director, Seyed E. Hasnain (former vice-chancellor of the University of Hyderabad), who pursued this aim aggressively during his tenure from 1999 to 2005. The centre is equipped with instrumentation and computing infrastructure to facilitate working in frontier areas of research in life sciences. There are twenty-two groups working on diverse research areas and the centre continues to attract leaders in related disciplines.
Campus
CDFD started its operations at the Centre for Cellular and Molecular Biology, a Council of Scientific and Industrial Research organisation, and was housed in an interim building in Nacharam from early 1999 to December 2008.
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https://en.wikipedia.org/wiki/Structural%20mechanics
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Structural mechanics or mechanics of structures is the computation of deformations, deflections, and internal forces or stresses (stress equivalents) within structures, either for design or for performance evaluation of existing structures. It is one subset of structural analysis. Structural mechanics analysis needs input data such as structural loads, the structure's geometric representation and support conditions, and the materials' properties. Output quantities may include support reactions, stresses and displacements. Advanced structural mechanics may include the effects of stability and non-linear behaviors.
Mechanics of structures is a field of study within applied mechanics that investigates the behavior of structures under mechanical loads, such as bending of a beam, buckling of a column, torsion of a shaft, deflection of a thin shell, and vibration of a bridge.
There are three approaches to the analysis: the energy methods, flexibility method or direct stiffness method which later developed into finite element method and the plastic analysis approach.
Energy method
Energy principles in structural mechanics
Flexibility method
Flexibility method
Stiffness methods
Direct stiffness method
Finite element method in structural mechanics
Plastic analysis approach
Plastic Analysis
Major topics
Beam theory
Buckling
Earthquake engineering
Finite element method in structural mechanics
Plates and shells
Torsion
Trusses
Stiffening
Structural dynamics
Structural instability
Building engineering
Structural engineering
Solid mechanics
Mechanics
Earthquake engineering
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https://en.wikipedia.org/wiki/Initialization-on-demand%20holder%20idiom
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In software engineering, the initialization-on-demand holder (design pattern) idiom is a lazy-loaded singleton. In all versions of Java, the idiom enables a safe, highly concurrent lazy initialization of static fields with good performance.
public class Something {
private Something() {}
private static class LazyHolder {
static final Something INSTANCE = new Something();
}
public static Something getInstance() {
return LazyHolder.INSTANCE;
}
}
The implementation of the idiom relies on the initialization phase of execution within the Java Virtual Machine (JVM) as specified by the Java Language Specification (JLS). When the class Something is loaded by the JVM, the class goes through initialization. Since the class does not have any static variables to initialize, the initialization completes trivially. The static class definition LazyHolder within it is not initialized until the JVM determines that LazyHolder must be executed. The static class LazyHolder is only executed when the static method getInstance is invoked on the class Something, and the first time this happens the JVM will load and initialize the LazyHolder class. The initialization of the LazyHolder class results in static variable INSTANCE being initialized by executing the (private) constructor for the outer class Something. Since the class initialization phase is guaranteed by the JLS to be sequential, i.e., non-concurrent, no further synchronization is required in the static getInstance method during loading and initialization. And since the initialization phase writes the static variable INSTANCE in a sequential operation, all subsequent concurrent invocations of the getInstance will return the same correctly initialized INSTANCE without incurring any additional synchronization overhead.
Caveats
While the implementation is an efficient thread-safe "singleton" cache without synchronization overhead, and better performing than uncontended synchronization, the i
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https://en.wikipedia.org/wiki/Accessible%20surface%20area
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The accessible surface area (ASA) or solvent-accessible surface area (SASA) is the surface area of a biomolecule that is accessible to a solvent. Measurement of ASA is usually described in units of square angstroms (a standard unit of measurement in molecular biology). ASA was first described by Lee & Richards in 1971 and is sometimes called the Lee-Richards molecular surface. ASA is typically calculated using the 'rolling ball' algorithm developed by Shrake & Rupley in 1973. This algorithm uses a sphere (of solvent) of a particular radius to 'probe' the surface of the molecule.
Methods of calculating ASA
Shrake–Rupley algorithm
The Shrake–Rupley algorithm is a numerical method that draws a mesh of points equidistant from each atom of the molecule and uses the number of these points that are solvent accessible to determine the surface area. The points are drawn at a water molecule's estimated radius beyond the van der Waals radius, which is effectively similar to ‘rolling a ball’ along the surface. All points are checked against the surface of neighboring atoms to determine whether they are buried or accessible. The number of points accessible is multiplied by the portion of surface area each point represents to calculate the ASA. The choice of the 'probe radius' does have an effect on the observed surface area, as using a smaller probe radius detects more surface details and therefore reports a larger surface. A typical value is 1.4Å, which approximates the radius of a water molecule. Another factor that affects the results is the definition of the VDW radii of the atoms in the molecule under study. For example, the molecule may often lack hydrogen atoms, which are implicit in the structure. The hydrogen atoms may be implicitly included in the atomic radii of the 'heavy' atoms, with a measure called the 'group radii'. In addition, the number of points created on the van der Waals surface of each atom determines another aspect of discretization, where more points
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https://en.wikipedia.org/wiki/Follistatin
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Follistatin also known as activin-binding protein is a protein that in humans is encoded by the FST gene. Follistatin is an autocrine glycoprotein that is expressed in nearly all tissues of higher animals.
Its primary function is the binding and bioneutralization of members of the TGF-β superfamily, with a particular focus on activin, a paracrine hormone.
An earlier name for the same protein was FSH-suppressing protein (FSP). At the time of its initial isolation from follicular fluid, it was found to inhibit the anterior pituitary's secretion of follicle-stimulating hormone (FSH).
Biochemistry
Follistatin is part of the inhibin-activin-follistatin axis.
Currently there are three reported isoforms, FS-288, FS-300, and FS-315.
Two, FS-288 and FS-315, are known to be created by alternative splicing of the primary mRNA transcript. FS-300 (porcine follistatin) is thought to be the product of posttranslational modification via truncation of the C-terminal domain from the primary amino-acid chain.
Although FS is ubiquitous its highest concentration has been found to be in the female ovary, followed by the skin.
The activin-binding protein follistatin is produced by folliculostellate (FS) cells of the anterior pituitary. FS cells make numerous contacts with the classical endocrine cells of the anterior pituitary including gonadotrophs.
In the tissues activin has a strong role in cellular proliferation, thereby making follistatin the safeguard against uncontrolled cellular proliferation and also allowing it to function as an instrument of cellular differentiation. Both of these roles are vital in tissue rebuilding and repair, and may account for follistatin's high presence in the skin.
In the blood, activin and follistatin are both known to be involved in the inflammatory response following tissue injury or pathogenic incursion. The source of follistatin in circulating blood plasma has yet to be determined, but due to its autocrine nature speculation suggests t
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https://en.wikipedia.org/wiki/Prickle%20%28protein%29
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Prickle is also known as REST/NRSF-interacting LIM domain protein, which is a putative nuclear translocation receptor. Prickle is part of the non-canonical Wnt signaling pathway that establishes planar cell polarity. A gain or loss of function of Prickle1 causes defects in the convergent extension movements of gastrulation. In epithelial cells, Prickle2 establishes and maintains cell apical/basal polarity. Prickle1 plays an important role in the development of the nervous system by regulating the movement of nerve cells.
The first prickle protein was identified in Drosophila as a planar cell polarity protein. Vertebrate prickle-1 was first found as a rat protein that binds to a transcription factor, neuron-restrictive silencer factor (NRSF). It was then recognized that other vertebrates including mice and humans have two genes that are related to Drosophila prickle. Mouse prickle-2 was found to be expressed in mature neurons of the brain along with mouse homologs of Drosophila planar polarity genes flamingo and dischevelled. Prickle interacts with flamingo to regulate sensory axon advance at the transition between the peripheral nervous system and the central nervous system. Also, Prickle1 interacts with RE1-silencing transcription factor (REST) by transporting REST out of the nucleus. REST turns off several critical genes in neurons by binding to particular regions of DNA in the nucleus.
Prickle is recruited to the cell surface membrane by strabismus, another planar cell polarity protein. In the developing Drosophila wing, prickle becomes concentrated at the proximal side of cells. Prickle can compete with the ankyrin-repeat protein Diego for a binding site on Dishevelled.
In Drosophila, prickle is present inside cells in multiple forms due to alternative splicing of the prickle mRNA. The relative levels of the alternate forms may be regulated and involved in the normal control of planar cell polarity.
Mutations in Prickle genes can cause epilepsy in humans by
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https://en.wikipedia.org/wiki/Laboratori%20Nazionali%20del%20Gran%20Sasso
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Laboratori Nazionali del Gran Sasso (LNGS) is the largest underground research center in the world. Situated below Gran Sasso mountain in Italy, it is well known for particle physics research by the INFN. In addition to a surface portion of the laboratory, there are extensive underground facilities beneath the mountain. The nearest towns are L'Aquila and Teramo. The facility is located about 120 km from Rome.
The primary mission of the laboratory is to host experiments that require a low background environment in the fields of astroparticle physics and nuclear astrophysics and other disciplines that can profit of its characteristics and of its infrastructures.
The LNGS is, like the three other European underground astroparticle laboratories (Laboratoire Souterrain de Modane, Laboratorio subterráneo de Canfranc, and Boulby Underground Laboratory), a member of the coordinating group ILIAS.
Facilities
The laboratory consists of a surface facility, located within the Gran Sasso and Monti della Laga National Park, and extensive underground facilities located next to the 10 km long Traforo del Gran Sasso freeway tunnel.
The first large experiments at LNGS ran in 1989; the facilities were later expanded, and it is now the largest underground laboratory in the world.
There are three main barrel vaulted experimental halls, each approximately 20 m wide, 18 m tall, and 100 m long. These provide roughly 3×20×100= of floor space and 3×20×(8+10×π/4)×100= of volume. Including smaller spaces and various connecting tunnels, the facility totals and .
The experimental halls are covered by about 1400 m of rock, protecting the experiments from cosmic rays. Providing about 3400 metres of water equivalent (mwe) shielding, it is not the deepest underground laboratory, but the fact that it can be driven to without using mine elevators makes it very popular.
Research projects
Neutrino research
Since late August 2006, CERN has directed a beam of muon neutrinos from the CERN SPS accele
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https://en.wikipedia.org/wiki/Lefty%20%28protein%29
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Lefty (left-right determination factors) are a class of proteins that are closely related members of the TGF-beta superfamily of growth factors. These proteins are secreted and play a role in left-right asymmetry determination of organ systems during development. Mutations of the genes encoding these proteins have been associated with left-right axis malformations, particularly in the heart and lungs.
History
Lefty, a divergent member of the transforming growth factor-β (TGF beta) superfamily of proteins, was originally discovered in the Hamada lab at the Osaka University using deletion screening of cDNA libraries in P19 embryonic carcinoma cells to find clones that did not differentiate when induced to differentiate using retinoic acid. From these screens, researchers found one gene that was a tentative member of the TGF-beta superfamily that was predominantly expressed on the left side the embryo and aptly named it lefty. Like other members of the TGF-beta superfamily, lefty is synthesized as a preproprotein, meaning that the protein is proteolytically cleaved and excreted to produce the active form of the protein. However, lefty has only 20-25% sequence similarity with other members of the TGF-beta superfamily. Lefty is conserved in all vertebrates and many species have more than one homologue. Humans and mice, for instance have two homologues, Lefty 1 and Lefty 2, whose differential expression leads to distinct purposes while the mechanism of action is conserved.
Function
Lefty proteins function as an antagonist of the Nodal Signaling pathway. Nodal is another signaling protein which is responsible for gastrulation, left-right patterning and induction of the primitive node. As NODAL protein diffuse through an embryo, it triggers Nodal Signaling within tissues with the required receptors and coreceptors. Activated nodal signaling leads to the transcription of the lefty gene. The protein is then expressed, proteolytically cleaved, and finally secreted. Secrete
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https://en.wikipedia.org/wiki/Tractor%20bundle
|
In conformal geometry, the tractor bundle is a particular vector bundle constructed on a conformal manifold whose fibres form an effective representation of the conformal group (see associated bundle).
The term tractor is a portmanteau of "Tracy Thomas" and "twistor", the bundle having been introduced first by T. Y. Thomas as an alternative formulation of the Cartan conformal connection, and later rediscovered within the formalism of local twistors and generalized to projective connections by Michael Eastwood et al. in
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https://en.wikipedia.org/wiki/BackTrack
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BackTrack was a Linux distribution that focused on security, based on the Knoppix Linux distribution aimed at digital forensics and penetration testing use. In March 2013, the Offensive Security team rebuilt BackTrack around the Debian distribution and released it under the name Kali Linux.
History
The BackTrack distribution originated from the merger of two formerly competing distributions which focused on penetration testing:
WHAX: a Slax-based Linux distribution developed by Mati Aharoni, a security consultant. Earlier versions of WHAX were called Whoppix and were based on Knoppix.
Auditor Security Collection: a Live CD based on Knoppix developed by Max Moser which included over 300 tools organized in a user-friendly hierarchy.
On January 9, 2010, BackTrack 4 improved hardware support, and added official FluxBox support. The overlap with Auditor and WHAX in purpose and in collection of tools partly led to the merger. The overlap was done based on Ubuntu Lucid LTS starting from BackTrack 5.
Tools
BackTrack provided users with easy access to a comprehensive and large collection of security-related tools ranging from port scanners to Security Audit. Support for Live CD and Live USB functionality allowed users to boot BackTrack directly from portable media without requiring installation, though permanent installation to hard disk and network was also an option.
BackTrack included many well known security tools including:
Metasploit for integration
Wi-Fi drivers supporting monitor mode (rfmon mode) and packet injection
Aircrack-ng
Reaver, a tool used to exploit a vulnerability in WPS
Gerix Wifi Cracker
Kismet
Nmap
Ophcrack
Ettercap
Wireshark (formerly known as Ethereal)
BeEF (Browser Exploitation Framework)
Hydra
OWASP Mantra Security Framework, a collection of hacking tools, add-ons and scripts based on Firefox
Cisco OCS Mass Scanner, a very reliable and fast scanner for Cisco routers to test default telnet and enabling password.
A large collec
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https://en.wikipedia.org/wiki/Conformal%20connection
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In conformal differential geometry, a conformal connection is a Cartan connection on an n-dimensional manifold M arising as a deformation of the Klein geometry given by the celestial n-sphere, viewed as the homogeneous space
O+(n+1,1)/P
where P is the stabilizer of a fixed null line through the origin in Rn+2, in the orthochronous Lorentz group O+(n+1,1) in n+2 dimensions.
Normal Cartan connection
Any manifold equipped with a conformal structure has a canonical conformal connection called the normal Cartan connection.
Formal definition
A conformal connection on an n-manifold M is a Cartan geometry modelled on the conformal sphere, where the latter is viewed as a homogeneous space for O+(n+1,1). In other words, it is an O+(n+1,1)-bundle equipped with
a O+(n+1,1)-connection (the Cartan connection)
a reduction of structure group to the stabilizer of a point in the conformal sphere (a null line in Rn+1,1)
such that the solder form induced by these data is an isomorphism.
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https://en.wikipedia.org/wiki/Avermectin
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The avermectins are a series of drugs and pesticides used to treat parasitic worms and insect pests. They are a group of 16-membered macrocyclic lactone derivatives with potent anthelmintic and insecticidal properties. These naturally occurring compounds are generated as fermentation products by Streptomyces avermitilis, a soil actinomycete. Eight different avermectins were isolated in four pairs of homologue compounds (A1, A2, B1, B2), with a major (a-component) and minor (b-component) component usually in ratios of 80:20 to 90:10. Avermectin B1, a mixture of B1a and B1b, is the drug and pesticide abamectin. Other anthelmintics derived from the avermectins include ivermectin, selamectin, doramectin, eprinomectin.
Half of the 2015 Nobel Prize in Physiology or Medicine was awarded to William C. Campbell and Satoshi Ōmura for discovering avermectin, "the derivatives of which have radically lowered the incidence of river blindness and lymphatic filariasis, as well as showing efficacy against an expanding number of other parasitic diseases."
History
In 1978, an actinomycete was isolated at the Kitasato Institute from a soil sample collected at Kawana, Ito City, Shizuoka Prefecture, Japan. Later that year, the isolated actinomycete was sent to Merck Sharp and Dohme Research Laboratories for testing. Various carefully controlled broths were fermented using the isolated actinomycete. Early tests indicated that some of the whole, fermented broths were active against Nematospiroides dubius in mice over at least an eight-fold range without notable toxicity. Subsequent to this, the anthelmintic activity was isolated and identified as a family of closely related compounds. The compounds were finally characterized and the novel species that produced them were described by a team at Merck in 1978, and named Streptomyces avermitilis (with the adjective probably intended to mean that it kills worms).
In 2002, Yoko Takahashi and others at the Kitasato Institute for Life Scien
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