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https://en.wikipedia.org/wiki/Fritz%20Ullmann
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Fritz Ullmann (July 2, 1875 in Fürth – March 17, 1939 in Berlin) was a German chemist.
Ullmann was born in Fürth and started studying chemistry in Nuremberg, but received his PhD of the University of Geneva for work with Carl Gräbe in 1895. After some time in Geneva he went to Berlin in 1905.
Ullmann taught technical chemistry during 1905-1913 and 1922-1925 at the Technischen Hochschule Berlin now Technische Universität Berlin, first as part of the ordinary teaching staff, later on as a professor.
In 1900 he introduced dimethyl sulfate as an alkylating agent. Between 1914 and 1922, when he was back in Geneva, he published the first edition of the "Enzyklopädie der Technischen Chemie" in 12 volumes () in English the Ullmann's Encyclopedia of Industrial Chemistry, a publication that exists to this day. He was married to Irma Goldberg who was his assistant from 1905 to 1910 at his laboratory.
They named after themselves the following reactions: the Ullmann reaction, the Ullmann condensation, the Graebe-Ullmann synthesis, the Goldberg reaction and the illustrious Jordan-Ullmann-Goldberg synthesis.
References
20th-century German chemists
Academic staff of the Technical University of Berlin
University of Geneva alumni
People from Fürth
1875 births
1939 deaths
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https://en.wikipedia.org/wiki/Genome%20Research
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Genome Research is a peer-reviewed scientific journal published by Cold Spring Harbor Laboratory Press. Disregarding review journals, Genome Research ranks 2nd in the category 'Genetics and Genomics' after Nature Genetics. The focus of the journal is on research that provides novel insights into the genome biology of all organisms, including advances in genomic medicine. This scope includes genome structure and function, comparative genomics, molecular evolution, genome-scale quantitative and population genetics, proteomics, epigenomics, and systems biology. The journal also features interesting gene discoveries and reports of cutting-edge computational biology and high-throughput biology methodologies. New data in these areas are published as research papers, or methods and resource reports that provide novel information on technologies or tools that will be of interest to a broad readership. The journal was established in 1991 as PCR Methods and Applications and obtained its current title in 1995. According to the Journal Citation Reports, the journal has a 2020 impact factor of 9.043, which peaked in 2014 at 14.630.
References
External links
Genetic engineering journals
Delayed open access journals
Academic journals established in 1991
Cold Spring Harbor Laboratory Press academic journals
Monthly journals
English-language journals
1991 establishments in New York (state)
Genomics journals
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https://en.wikipedia.org/wiki/The%20Sex%20Files
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The Sex Files is a television program broadcasting on Discovery Channel Canada and was broadcast on CTV network stations after the watershed, due to its highly explicit discussion of the nature of sexuality issues and behavior, from genetics, reproduction, sexual orientation, puberty, etc. As one would expect of a show of its nature, it frequently featured nudity, but portrayed in a scientific manner for visually aid in learning, highly beneficial information on sexuality and the biology behind it. In Europe the show was called Sex Sense and featured a male narrator. The number of episodes and their titles were the same, but the episodes themselves were slightly different as the more explicit scenes were replaced. It aired on Discovery Channel Europe.
Starting with episode 41 (season 4), it is broadcast in high-definition.
The Sex Files episode list
Season 1
The Erection
Breasts
Orgasm
The Birds and the Bees
Aphrodisiacs
Fantasy
The Affair
Fetish
Gender
Hair
What is Sexy?
Girl Power
Birth Control
Season 2
Sex Drive
The Act
The Vagina
Sexual Signals
Sexual Senses
Sex for One
Puberty
Homosexuality
The Rear End
Sexual Cycle
Love Juices
Circumcision
Intersexed People
Myths
Season 3
Testicles
Celibacy
Behavioral addiction
Better Sex
Sexual Reconstruction
Menopause
Future Sex
Sex & Culture
Sex & Disabilities
Sex vs. Love
Healing Sex
Pregnancy
Sexpertise
Season 4
Sex Toys
Kinky Sex
Rated X
Beyond Monogamy
Pleasure and Pain
The Kiss
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https://en.wikipedia.org/wiki/Stagnation%20point
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In fluid dynamics, a stagnation point is a point in a flow field where the local velocity of the fluid is zero. A plentiful, albeit surprising, example of such points seem to appear in all but the most extreme cases of fluid dynamics in the form of the "no-slip condition"; the assumption that any portion of a flow field lying along some boundary consists of nothing but stagnation points (the question as to whether this assumption reflects reality or is simply a mathematical convenience has been a continuous subject of debate since the principle was first established). The Bernoulli equation shows that the static pressure is highest when the velocity is zero and hence static pressure is at its maximum value at stagnation points: in this case static pressure equals stagnation pressure.
The Bernoulli equation applicable to incompressible flow shows that the stagnation pressure is equal to the dynamic pressure plus static pressure. Total pressure is also equal to dynamic pressure plus static pressure so, in incompressible flows, stagnation pressure is equal to total pressure. (In compressible flows, stagnation pressure is also equal to total pressure providing the fluid entering the stagnation point is brought to rest isentropically.)
Pressure coefficient
This information can be used to show that the pressure coefficient at a stagnation point is unity (positive one):
where:
is pressure coefficient
is static pressure at the point at which pressure coefficient is being eva
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https://en.wikipedia.org/wiki/Nuclear%20reaction%20analysis
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Nuclear reaction analysis (NRA) is a nuclear method of nuclear spectroscopy in materials science to obtain concentration vs. depth distributions for certain target chemical elements in a solid thin film.
Mechanism of NRA
If irradiated with select projectile nuclei at kinetic energies Ekin, target solid thin-film chemical elements can undergo a nuclear reaction under resonance conditions for a sharply defined resonance energy. The reaction product is usually a nucleus in an excited state which immediately decays, emitting ionizing radiation.
To obtain depth information the initial kinetic energy of the projectile nucleus (which has to exceed the resonance energy) and its stopping power (energy loss per distance traveled) in the sample has to be known. To contribute to the nuclear reaction the projectile nuclei have to slow down in the sample to reach the resonance energy. Thus each initial kinetic energy corresponds to a depth in the sample where the reaction occurs (the higher the energy, the deeper the reaction).
NRA profiling of hydrogen
For example, a commonly used reaction to profile hydrogen with an energetic 15N ion beam is
15N + 1H → 12C + α + γ (4.43 MeV)
with a sharp resonance in the reaction cross section at 6.385 MeV of only 1.8 keV. Since the incident 15N ion loses energy along its trajectory in the material it must have an energy higher than the resonance energy to induce the nuclear reaction with hydrogen nuclei deeper in the target.
This reaction is u
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https://en.wikipedia.org/wiki/Dirichlet%20beta%20function
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In mathematics, the Dirichlet beta function (also known as the Catalan beta function) is a special function, closely related to the Riemann zeta function. It is a particular Dirichlet L-function, the L-function for the alternating character of period four.
Definition
The Dirichlet beta function is defined as
or, equivalently,
In each case, it is assumed that Re(s) > 0.
Alternatively, the following definition, in terms of the Hurwitz zeta function, is valid in the whole complex s-plane:
Another equivalent definition, in terms of the Lerch transcendent, is:
which is once again valid for all complex values of s.
The Dirichlet beta function can also be written in terms of the polylogarithm function:
Also the series representation of Dirichlet beta function can be formed in terms of the polygamma function
but this formula is only valid at positive integer values of .
Euler product formula
It is also the simplest example of a series non-directly related to which can also be factorized as an Euler product, thus leading to the idea of Dirichlet character defining the exact set of Dirichlet series having a factorization over the prime numbers.
At least for Re(s) ≥ 1:
where are the primes of the form (5,13,17,...) and are the primes of the form (3,7,11,...). This can be written compactly as
Functional equation
The functional equation extends the beta function to the left side of the complex plane Re(s) ≤ 0. It is given by
where Γ(s) is the gamma function. It was co
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https://en.wikipedia.org/wiki/Joachim%20Sauer
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Joachim Sauer (; born 19 April 1949) is a German quantum chemist and professor emeritus of physical and theoretical chemistry at the Humboldt University of Berlin. He is the husband of the former chancellor of Germany, Angela Merkel. He is one of the seven members of the board of trustees of the Friede Springer Foundation, together with former German president Horst Köhler and others.
Education and early life
Joachim Sauer was born in Hosena, a small town in the marshy Lusatian countryside between Dresden and Cottbus. He grew up with his twin sister and an elder brother. His father, Richard Sauer, had trained as a confectioner, but worked as an insurance representative. Sauer excelled at school.
Career and research
Sauer studied chemistry from 1967 to 1972 at the Humboldt University of Berlin and was awarded a doctorate in chemistry in 1974. He continued to do research there until 1977, when he joined the Academy of Sciences, Central Institute of Physical Chemistry in Berlin, one of the leading scientific institutes of the former GDR (East Germany)
For a brief time during and after the German reunification (1990–1991) he was the deputy technical director (catalysis and sorption) for BIOSYM Technologies in San Diego, California (now BIOVIA). He remained an advisor for BIOSYM until 2002.
In 1992, he joined the Max Planck Society as head of the Quantum Chemistry Group in Berlin. In 1993, he became full professor of physical and theoretical chemistry at the Humboldt Univer
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https://en.wikipedia.org/wiki/Ap%C3%A9ry%27s%20constant
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In mathematics, Apéry's constant is the sum of the reciprocals of the positive cubes. That is, it is defined as the number
where is the Riemann zeta function. It has an approximate value of
.
The constant is named after Roger Apéry. It arises naturally in a number of physical problems, including in the second- and third-order terms of the electron's gyromagnetic ratio using quantum electrodynamics. It also arises in the analysis of random minimum spanning trees and in conjunction with the gamma function when solving certain integrals involving exponential functions in a quotient, which appear occasionally in physics, for instance, when evaluating the two-dimensional case of the Debye model and the Stefan–Boltzmann law.
Irrational number
was named Apéry's constant after the French mathematician Roger Apéry, who proved in 1978 that it is an irrational number. This result is known as Apéry's theorem. The original proof is complex and hard to grasp, and simpler proofs were found later.
Beukers's simplified irrationality proof involves approximating the integrand of the known triple integral for ,
by the Legendre polynomials.
In particular, van der Poorten's article chronicles this approach by noting that
where , are the Legendre polynomials, and the subsequences are integers or almost integers.
It is still not known whether Apéry's constant is transcendental.
Series representations
Classical
In addition to the fundamental series:
Leonhard Euler gave the s
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https://en.wikipedia.org/wiki/Solenoid%20%28mathematics%29
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This page discusses a class of topological groups. For the wrapped loop of wire, see Solenoid.
In mathematics, a solenoid is a compact connected topological space (i.e. a continuum) that may be obtained as the inverse limit of an inverse system of topological groups and continuous homomorphisms
where each is a circle and fi is the map that uniformly wraps the circle for times () around the circle . This construction can be carried out geometrically in the three-dimensional Euclidean space R3. A solenoid is a one-dimensional homogeneous indecomposable continuum that has the structure of a compact topological group.
Solenoids were first introduced by Vietoris for the case, and by van Dantzig the case, where is fixed. Such a solenoid arises as a one-dimensional expanding attractor, or Smale–Williams attractor, and forms an important example in the theory of hyperbolic dynamical systems.
Construction
Geometric construction and the Smale–Williams attractor
Each solenoid may be constructed as the intersection of a nested system of embedded solid tori in R3.
Fix a sequence of natural numbers {ni}, ni ≥ 2. Let T0 = S1 × D be a solid torus. For each i ≥ 0, choose a solid torus Ti+1 that is wrapped longitudinally ni times inside the solid torus Ti. Then their intersection
is homeomorphic to the solenoid constructed as the inverse limit of the system of circles with the maps determined by the sequence {ni}.
Here is a variant of this construction isolated by Stephen Sm
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https://en.wikipedia.org/wiki/Blum%20integer
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In mathematics, a natural number n is a Blum integer if is a semiprime for which p and q are distinct prime numbers congruent to 3 mod 4. That is, p and q must be of the form , for some integer t. Integers of this form are referred to as Blum primes. This means that the factors of a Blum integer are Gaussian primes with no imaginary part. The first few Blum integers are
21, 33, 57, 69, 77, 93, 129, 133, 141, 161, 177, 201, 209, 213, 217, 237, 249, 253, 301, 309, 321, 329, 341, 381, 393, 413, 417, 437, 453, 469, 473, 489, 497, ...
The integers were named for computer scientist Manuel Blum.
Properties
Given a Blum integer, Qn the set of all quadratic residues modulo n and coprime to n and . Then:
a has four square roots modulo n, exactly one of which is also in Qn
The unique square root of a in Qn is called the principal square root of a modulo n
The function f : Qn → Qn defined by f(x) = x2 mod n is a permutation. The inverse function of f is: f(x) = .
For every Blum integer n, −1 has a Jacobi symbol mod n of +1, although −1 is not a quadratic residue of n:
History
Before modern factoring algorithms, such as MPQS and NFS, were developed, it was thought to be useful to select Blum integers as RSA moduli. This is no longer regarded as a useful precaution, since MPQS and NFS are able to factor Blum integers with the same ease as RSA moduli constructed from randomly selected primes.
References
Integer sequences
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https://en.wikipedia.org/wiki/Bishop%20Stopford%27s%20School
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Bishop Stopford's School, commonly known as Bishop Stopford's, or (simply) just Bishop's, is a voluntary aided co-educational secondary school specialising in mathematics, computing and engineering, with a sixth form. It is a London Diocesan Church of England school with worship in a relatively High Church Anglo-Catholic tradition. It is in Brick Lane, Enfield, near Enfield Highway, Greater London, England.
Overview
Bishop Stopford's has about 920 pupils aged 11 to 19. In 2004 the school received an award for mathematics and computing and in 2008 engineering specialist status.
Key Stage 3
At Key Stage 3 pupils follow the same subjects for years 7–9. All pupils start to take French in Year 7.
GCSE
In Year 9 pupils can choose what subjects they wish to take for their GCSEs. All pupils take maths, science, English language, English literature, religious education, and physical education.
Sixth form
Entry to the Sixth Form is subject to a satisfactory report from the Year 11 Head of House and an interview with the Head of the Sixth Form or other relevant teacher. In the sixth form, pupils again choose what they wish to study. There are two routes which they may take. Pupils may take a 1-year BTEC course in either OCR business studies or BTEC art and design, or AS/A2 levels. The conditions for taking AS/A2 Levels are:
a minimum of 5 A* to C grades at GCSE level in a suitable combination of subjects, and C grades or better in English Language, Literature, and Maths.
a rec
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https://en.wikipedia.org/wiki/Adatom
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An adatom is an atom that lies on a crystal surface, and can be thought of as the opposite of a surface vacancy. This term is used in surface chemistry and epitaxy, when describing single atoms lying on surfaces and surface roughness. The word is a portmanteau of "adsorbed atom". A single atom, a cluster of atoms, or a molecule or cluster of molecules may all be referred to by the general term "adparticle". This is often a thermodynamically unfavorable state. However, cases such as graphene may provide counter-examples.
Adatom growth
″Adatom″ is a portmanteau word, short for adsorbed atom. When the atom arrives at a crystal surface, it is adsorbed by the periodic potential of the crystal, thus becoming an adatom. The minima of this potential form a network of adsorption sites on the surface. There are different types of adsorption sites. Each of these sites corresponds to a different structure of the surface. There are five different types of adsorption sites, which are: on a terrace, where the adsorption site is on top of the surface layer that is growing; at the step edge, which is next to the growing layer; in the kink of a growing layer; in the step edge of a growing layer, and in the surface layer, where the adsorption site is inside the lower layer.
Out of these adsorption site types, kink sites play the most important role in crystal growth. Kink density is a major factor of growth kinetics. Attachment of an atom to the kink site, or removal of the atom from the
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https://en.wikipedia.org/wiki/Thrust%20%28disambiguation%29
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Thrust is a reaction force described by Newton's Second and Third Laws.
Thrust may also refer to:
Thrust fault, in geology
Thrust block, a specialised form of thrust bearing used in ships
Thrust (particle physics), a quantity that characterizes the collision of high energy particles in a collider
Thrust bearing, particular type of rotary bearing
ThrustSSC, and Thrust2, the land-speed record breaking cars
Thrust (video game), a computer game
Thrust (rapper), a Canadian hip hop artist
Thrust (science fiction magazine), a 1973–1991 American fanzine
Thrust (album), a Herbie Hancock fusion album
Thrust stage, in a theatre, a portion of the stage that extends out from the proscenium into the audience
Tongue thrust
Pelvic thrust
See also
Thruster (disambiguation)
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https://en.wikipedia.org/wiki/Catherine%20wheel%20%28firework%29
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The Catherine wheel or pinwheel is a type of firework consisting either of a powder-filled spiral tube, or an angled rocket mounted with a pin through its center. When ignited, the energy of the fireworks not only create sparks and flame, but cause the wheel to quickly rotate, making the display much more spectacular. The physics of the process are those of an aeolipile.
The firework is named after Saint Catherine of Alexandria who, according to Christian tradition, was condemned to death by “breaking on the wheel”. When she touched the wheel it miraculously fell to pieces.
The largest Catherine wheel ever made was designed by the Lily Fireworks Factory of Mqabba, Malta. The Catherine wheel had a diameter of , and was lit on 18 June 2011, the eve of the annual feast of Our Lady of the Lilies.In Malta, Catherine wheels are a traditional fixture during every village 'festa'. Some villages even hold competitions on the eve of the parish feast, while others display the vast work of one firework. Entrants display a variety of moving shapes and include various colours year after year as the technology progresses. These displays are only a small part of the firework catalogue planned throughout the week preceding the feast and on the feast day itself. The Catherine wheel displays typically end with the burning of what is called 'the carpet': the largest Catherine wheel in the display on the night.
In the Philippines, Catherine wheel is also known as trompillo and according to Re
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https://en.wikipedia.org/wiki/Callus%20%28disambiguation%29
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Callus is an area of toughened skin.
Callus may also refer to:
Fibrocartilage callus, the temporary new bony tissue that forms at the ends of a fractured bone
Callus (botany), a fleshy lump of tissue on the labellum (or lip) of orchid flowers
Callus (cell biology), a mass of unorganized cells
Callus (mollusc), a thickened layer of shell material
Callus (album), a 2016 album by Gonjasufi
See also
Calus (disambiguation)
Thick skin (disambiguation)
Callous, a trait where a person lacks empathy, or at least ignores it; hardhearted
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https://en.wikipedia.org/wiki/Ice%20%28disambiguation%29
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Ice is the solid form of water.
Ice or ICE may also refer to:
Computing and technology
ICE (scanning) (Image Correction and Enhancement), for removing surface defects from a scanned photo/image
In Case of Emergency, emergency numbers stored on a mobile or cellular phone
ICE (cipher), a block cipher in cryptography
iCE (FPGA), a programmable logic device family by Lattice Semiconductor
ICE validation, internal consistency evaluators, a set of tools for validating Windows Installer packages
IceWM, The Ice Window Manager
In-circuit emulation, a computer debugging hardware device
Information and Content Exchange, an XML protocol for content syndication
Integrated collaboration environment, a platform for virtual teams
Inter-Client Exchange, an X Window System protocol framework
Interactive Connectivity Establishment, a mechanism for NAT traversal
Interactive Creative Environment, a visual programming platform for Autodesk Softimage
Interactive customer evaluation, form technologies for collecting software user feedback
Interference cancellation equipment, in radio equipment such as cellular repeaters
Internal compiler error, a type of compilation error
International Cometary Explorer, a spacecraft for studying interaction between the Earth's magnetic field and solar wind
Internet Communications Engine, a computer software middleware platform developed by ZeroC
Microsoft Research Image Composite Editor, a panorama stitching program
Information, Communication,
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https://en.wikipedia.org/wiki/Rudder%20ratio
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Rudder ratio refers to a value that is monitored by the computerized flight control systems in modern aircraft. The ratio relates the aircraft airspeed to the rudder deflection setting that is in effect at the time. As an aircraft accelerates, the deflection of the rudder needs to be reduced proportionately within the range of the rudder pedal depression by the pilot. This automatic reduction process is needed because if the rudder is fully deflected when the aircraft is in high-speed flight, it will cause the plane to sharply and violently yaw, or swing from side to side, leading to loss of control and rudder, tail and other damages, even causing the aircraft to crash.
See also
American Airlines Flight 587
Aerospace engineering
Engineering ratios
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https://en.wikipedia.org/wiki/Max%20Planck%20Institute%20for%20Gravitational%20Physics
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The Max Planck Institute for Gravitational Physics (Albert Einstein Institute) is a Max Planck Institute whose research is aimed at investigating Einstein's theory of relativity and beyond: Mathematics, quantum gravity, astrophysical relativity, and gravitational-wave astronomy. The institute was founded in 1995 and is located in the Potsdam Science Park in Golm, Potsdam and in Hannover where it closely collaborates with the Leibniz University Hannover. Both the Potsdam and the Hannover parts of the institute are organized in three research departments and host a number of independent research groups.
The institute conducts fundamental research in mathematics, data analysis, astrophysics and theoretical physics as well as research in laser physics, vacuum technology, vibration isolation and classical and quantum optics.
When the LIGO Scientific Collaboration announced the first detection of gravitational waves, researchers of the institute were involved in modeling, detecting, analysing and characterising the signals. The institute is part of a number of collaborations and projects: it is a main partner in the gravitational-wave detector GEO600; institute scientists are developing waveform-models that are applied in the gravitational-wave detectors for detecting and characterising gravitational waves. They are developing detector technology and are also analyzing data from the detectors of the LIGO Scientific Collaboration, the Virgo Collaboration and the KAGRA Collaboratio
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https://en.wikipedia.org/wiki/Jean-Jacques%20Quisquater
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Jean-Jacques Quisquater (born 13 January 1945) is a Belgian cryptographer and a professor at University of Louvain (UCLouvain). He received, with Claus P. Schnorr, the RSA Award for Excellence in Mathematics in 2013, and the ESORICS Outstanding Research Award 2013.
On Saturday, 1 February 2014, Flemish public news agency VRT reported that about 6 months earlier, Quisquater's personal computer had been hacked. Since the same hacking technique was used at Belgium's public/private telecom provider Belgacom, VRT makes links to the NSA hacking scandal. Still according to VRT, a week before the article went out Edward Snowden warned about the NSA also targeting companies and private persons, in an interview with German television channel ARD. Belgian newspaper De Standaard mentions GCHQ and says the authorities are investigating the case. Reporters write Quisquater's computer was infected with malware after clicking a bogus invitation to join a social network—"that allowed the intruders to follow all of the professor's digital movements, including his work for international conferences on security".
References
External links
Quisquater's page, UCLouvain
1945 births
Living people
Belgian cryptographers
International Association for Cryptologic Research fellows
Modern cryptographers
Place of birth missing (living people)
Academic staff of the Université catholique de Louvain
Paris-Sud University alumni
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https://en.wikipedia.org/wiki/Cycles%20and%20fixed%20points
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In mathematics, the cycles of a permutation of a finite set S correspond bijectively to the orbits of the subgroup generated by acting on S. These orbits are subsets of S that can be written as , such that
for , and .
The corresponding cycle of is written as ( c1 c2 ... cn ); this expression is not unique since c1 can be chosen to be any element of the orbit.
The size of the orbit is called the length of the corresponding cycle; when , the single element in the orbit is called a fixed point of the permutation.
A permutation is determined by giving an expression for each of its cycles, and one notation for permutations consist of writing such expressions one after another in some order. For example, let
be a permutation that maps 1 to 2, 6 to 8, etc. Then one may write
= ( 1 2 4 3 ) ( 5 ) ( 6 8 ) (7) = (7) ( 1 2 4 3 ) ( 6 8 ) ( 5 ) = ( 4 3 1 2 ) ( 8 6 ) ( 5 ) (7) = ...
Here 5 and 7 are fixed points of , since (5) = 5 and (7)=7. It is typical, but not necessary, to not write the cycles of length one in such an expression. Thus, = (1 2 4 3)(6 8), would be an appropriate way to express this permutation.
There are different ways to write a permutation as a list of its cycles, but the number of cycles and their contents are given by the partition of S into orbits, and these are therefore the same for all such expressions.
Counting permutations by number of cycles
The unsigned Stirling number of the first kind, s(k, j) counts the number of permutations of k elemen
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https://en.wikipedia.org/wiki/Solid%20solution
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A solid solution, a term popularly used for metals, is a homogeneous mixture of two different kinds of atoms in solid state and having a single crystal structure. Many examples can be found in metallurgy, geology, and solid-state chemistry. The word "solution" is used to describe the intimate mixing of components at the atomic level and distinguishes these homogeneous materials from physical mixtures of components. Two terms are mainly associated with solid solutions – solvents and solutes, depending on the relative abundance of the atomic species.
In general if two compounds are isostructural then a solid solution will exist between the end members (also known as parents). For example sodium chloride and potassium chloride have the same cubic crystal structure so it is possible to make a pure compound with any ratio of sodium to potassium (Na1-xKx)Cl by dissolving that ratio of NaCl and KCl in water and then evaporating the solution. A member of this family is sold under the brand name Lo Salt which is (Na0.33K0.66)Cl, hence it contains 66% less sodium than normal table salt (NaCl). The pure minerals are called halite and sylvite; a physical mixture of the two is referred to as sylvinite.
Because minerals are natural materials they are prone to large variations in composition. In many cases specimens are members for a solid solution family and geologists find it more helpful to discuss the composition of the family than an individual specimen. Olivine is described by the f
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https://en.wikipedia.org/wiki/Irma%20Goldberg
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Irma Goldberg (born 1871) was one of the first female organic chemists to have and sustain a successful career, her work even being quoted in her own name in standard textbooks.
Life
Education
Born in Moscow to a Russian-Jewish family, she later traveled to Geneva in the 1890s to study chemistry at Geneva University.
Early research, Ullmann reaction
Her early research included the development of a process to remove sulfur and phosphorus from acetylene.
Her first article on the derivatives of benzophenone, coauthored by German chemist Fritz Ullmann, was published in 1897. She also researched and wrote a paper (published in 1904) on using copper as a catalyst for the preparation of a phenyl derivative of thiosalicylic acid, a process known as the Ullmann reaction; Goldberg is the only woman scientist unambiguously recognized for her own named reaction: the amidation (Goldberg) reaction. This modification to previous forms of the method was a great improvement, and was extremely helpful for laboratory-scale preparations. She coordinated on other forms of chemistry research with her husband, Fritz Ullmann, in what they called the Ullmann-Goldberg collaborative.
Move to Berlin, synthetic dye research
In 1905, both Goldberg and Ullman moved to Technische Hochschule in Berlin. Goldberg's research, along with that of the Ullmann-Goldberg collaborative, was also a part of Germany's synthetic dye industry. Their research helped with the creation of the synthetic alizarin industry,
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https://en.wikipedia.org/wiki/Promega
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Promega Corporation is a Madison, Wisconsinbased manufacturer of enzymes and other products for biotechnology and molecular biology with a portfolio covering the fields of genomics, protein analysis and expression, cellular analysis, drug discovery, and genetic identity.
History
Promega Corporation was founded by Bill Linton in 1978 to provide restriction enzymes for biotechnology. The company now offers more than 4,000 life science products used by scientists, researchers and life science and pharmaceutical companies. Promega has 1,601 employees. Revenue is approaching $450 million (USD) in 2019.
The privately held company has branch offices in 16 countries and more than 50 global distributors serving 100 countries. Promega Corporation also established the first biotechnology joint venture in China (Sino-American Biotechnology Co. in 1985).
The company has developed an on-site stocking system, which uses radio frequency identification (RFID) linked to the Internet to track and manage remote inventory. This resulted in the spin-off company Terso Solutions that specializes in the design and manufacturing of small RFID storage units.
In February 2020, Foreign Policy reported that Promega had sold equipment to the Xinjiang Production and Construction Corps. In 2021, The New York Times reported that, despite bans, Promega equipment continued to be sold to police in Xinjiang.
Product areas and technologies
Genomics
The company's portfolio began with products for genomic
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https://en.wikipedia.org/wiki/Society%20for%20Cryobiology
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The Society for Cryobiology is an international scientific society that was founded in 1964. Its objectives are to promote research in low temperature biology, to improve scientific understanding in this field, and to disseminate and aid in the application of this knowledge. The Society also publishes a journal called Cryobiology.
References
External links
Society for Cryobiology official site
Cryobiology
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https://en.wikipedia.org/wiki/Robert%20J.%20Weber
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Robert J. Weber (born April, 1947) is the Frederic E. Nemmers Distinguished Professor of Decision Sciences at the J.L. Kellogg Graduate School of Management, Northwestern University.
Biography
Education
Weber received his bachelor's degree in mathematics in 1969 from Princeton University, and both his MS in 1972 and Ph.D. in 1974 in operations research from Cornell University.
Career
Weber became a faculty member at Yale University, where he belonged to the Cowles Foundation for Research in Economics and the Yale School of Management. In 1979 he moved to Northwestern.
Weber's general area of research is game theory, with a primary focus on the effects of private information in competitive settings. Much of his research has been centered on the theory and practice of competitive bidding and auction design. His 1982 paper, "A Theory of Auctions and Competitive Bidding", co-authored with Paul Milgrom, is considered a seminal work in the field. In that paper the authors analyzed auctions with interdependent values, and introduced the linkage principle. He served as an external consultant on a 1985 project leading to revisions in the procedures used to auction petroleum extraction leases on the U.S. outer continental shelf, and he co-organized (with representatives of the Federal Reserve Board and the U.S. Treasury) the 1992 public forum which led to changes in the way the Treasury auctions its debt issues. Since 1993, he has represented private clients during both the rule-ma
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https://en.wikipedia.org/wiki/Baryon%20asymmetry
|
In physical cosmology, the baryon asymmetry problem, also known as the matter asymmetry problem or the matter–antimatter asymmetry problem, is the observed imbalance in baryonic matter (the type of matter experienced in everyday life) and antibaryonic matter in the observable universe. Neither the standard model of particle physics nor the theory of general relativity provides a known explanation for why this should be so, and it is a natural assumption that the universe is neutral with all conserved charges. The Big Bang should have produced equal amounts of matter and antimatter. Since this does not seem to have been the case, it is likely some physical laws must have acted differently or did not exist for matter and antimatter. Several competing hypotheses exist to explain the imbalance of matter and antimatter that resulted in baryogenesis. However, there is as of yet no consensus theory to explain the phenomenon, which has been described as "one of the great mysteries in physics".
Sakharov conditions
In 1967, Andrei Sakharov proposed a set of three necessary conditions that a baryon-generating interaction must satisfy to produce matter and antimatter at different rates. These conditions were inspired by the recent discoveries of the cosmic background radiation and CP violation in the neutral kaon system. The three necessary "Sakharov conditions" are:
Baryon number violation.
C-symmetry and CP-symmetry violation.
Interactions out of thermal equilibrium.
Baryon numb
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https://en.wikipedia.org/wiki/LSF
|
LSF may refer to:
Science and technology
IBM Spectrum LSF, a software job scheduler formerly called Platform LSF
Laser-stimulated fluorescence, a spectroscopic method
Late SV40 factor, a protein
Lightweight steel framing, a building material
Line spectral frequencies, in signal processing
Line spread function, in optics
Organisations
Financial Security Law of France ()
Ledøje-Smørum Fodbold, an association football club in Denmark
Other uses
French Sign Language ()
Latino sine flexione, a constructed language
"L.S.F." (song) or "L.S.F. (Lost Souls Forever)", by Kasabian
Law Society's Final Examination, replaced by the Legal Practice Course, UK
Liberty Security Force, a faction in the video game Freelancer
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https://en.wikipedia.org/wiki/Zorica%20Panti%C4%87
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Zorica Pantić, also known as Zorica Pantić-Tanner, born 1951 in Yugoslavia, is a professor of electrical engineering and past president of Wentworth Institute of Technology in Boston.
Pantić was previously the founding dean of the College of Engineering at the University of Texas at San Antonio, and director of the School of Engineering at San Francisco State University. She served as president of Wentworth Institute of Technology from 2005 to 2019.
Early life and education
Zorica Pantić received her B.S., M.S., and Ph.D. degrees in electrical engineering from the University of Niš, Yugoslavia (Serbia), in 1975, 1978, and 1982, respectively. She has 30 years of academic and teaching experience. She served on the engineering faculty of the University of Nis (1975–1984), San Francisco State University (1989–2001), and the University of Texas at San Antonio (2001–2004). She was a Fulbright Fellow and a visiting scientist at the University of Illinois at Urbana-Champaign from 1984-1989.
Career
Affiliations
She is a senior member of IEEE and served on various committees of the IEEE Electromagnetic Compatibility Society (EMC-S) until 2004. She served on the EMC-S Board of Directors and as chair, vice-chair, treasurer, and secretary of the Santa Clara Valley EMC-S Chapter. She is also a member of the American Society for Engineering Education and serves on the ASEE Projects Board, President's Award Committee, and Contact Committee.
She is a member of the IEEE Women in Enginee
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https://en.wikipedia.org/wiki/Mass%20flow%20rate
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In physics and engineering, mass flow rate is the mass of a substance which passes per unit of time. Its unit is kilogram per second in SI units, and slug per second or pound per second in US customary units. The common symbol is (ṁ, pronounced "m-dot"), although sometimes μ (Greek lowercase mu) is used.
Sometimes, mass flow rate is termed mass flux or mass current, see for example Schaum's Outline of Fluid Mechanics. In this article, the (more intuitive) definition is used.
Mass flow rate is defined by the limit:
i.e., the flow of mass through a surface per unit time .
The overdot on the is Newton's notation for a time derivative. Since mass is a scalar quantity, the mass flow rate (the time derivative of mass) is also a scalar quantity. The change in mass is the amount that flows after crossing the boundary for some time duration, not the initial amount of mass at the boundary minus the final amount at the boundary, since the change in mass flowing through the area would be zero for steady flow.
Alternative equations
Mass flow rate can also be calculated by
where
The above equation is only true for a flat, plane area. In general, including cases where the area is curved, the equation becomes a surface integral:
The area required to calculate the mass flow rate is real or imaginary, flat or curved, either as a cross-sectional area or a surface, e.g. for substances passing through a filter or a membrane, the real surface is the (generally curved) surface area of
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https://en.wikipedia.org/wiki/Somos%27%20quadratic%20recurrence%20constant
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In mathematics, Somos' quadratic recurrence constant, named after Michael Somos, is the number
This can be easily re-written into the far more quickly converging product representation
which can then be compactly represented in infinite product form by:
The constant σ arises when studying the asymptotic behaviour of the sequence
with first few terms 1, 1, 2, 12, 576, 1658880, ... . This sequence can be shown to have asymptotic behaviour as follows:
Guillera and Sondow give a representation in terms of the derivative of the Lerch transcendent:
where ln is the natural logarithm and (z, s, q) is the Lerch transcendent.
Finally,
.
Notes
References
Steven R. Finch, Mathematical Constants (2003), Cambridge University Press, p. 446. .
Jesus Guillera and Jonathan Sondow, "Double integrals and infinite products for some classical constants via analytic continuations of Lerch's transcendent", Ramanujan Journal 16 (2008), 247–270 (Provides an integral and a series representation).
Mathematical constants
Infinite products
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https://en.wikipedia.org/wiki/William%20Gemmell%20Cochran
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William Gemmell Cochran (15 July 1909 – 29 March 1980) was a prominent statistician. He was born in Scotland but spent most of his life in the United States.
Cochran studied mathematics at the University of Glasgow and the University of Cambridge. He worked at Rothamsted Experimental Station from 1934 to 1939, when he moved to the United States. There he helped establish several departments of statistics. His longest spell in any one university was at Harvard, which he joined in 1957 and from which he retired in 1976.
Writings
Cochran wrote many articles and books. His books became standard texts:
Experimental Designs (with Gertrude Mary Cox) 1950
Statistical Methods Applied to Experiments in Agriculture and Biology by George W. Snedecor (Cochran contributed from the fifth (1956) edition)
Planning and Analysis of Observational Studies (edited by Lincoln E. Moses and Frederick Mosteller) 1983.
References
External links
Brief biography
ASA biography
Morris Hansen and Frederick Mosteller (1987) William Gemmell Cochran NAS Biographical Memoirs V.56
Morris Hansen and Frederick Mosteller, "William Gemmell Cochran", Biographical Memoirs of the National Academy of Sciences (1987)
"Designing Clinical Trials" (1961; Evaluation of Drug Therapy)
1909 births
1980 deaths
American statisticians
British statisticians
Harvard University faculty
20th-century Scottish mathematicians
Presidents of the American Statistical Association
Presidents of the Institute of Mathemat
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https://en.wikipedia.org/wiki/Strong%20cryptography
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Strong cryptography or cryptographically strong are general terms used to designate the cryptographic algorithms that, when used correctly, provide a very high (usually unsurmountable) level of protection against any eavesdropper, including the government agencies. There is no precise definition of the boundary line between the strong cryptography and (breakable) weak cryptography, as this border constantly shifts due to improvements in hardware and cryptanalysis techniques. These improvements eventually place the capabilities once available only to the NSA within the reach of a skilled individual, so in practice there are only two levels of cryptographic security, "cryptography that will stop your kid sister from reading your files, and cryptography that will stop major governments from reading your files" (Bruce Schneier).
The strong cryptography algorithms have high security strength, for practical purposes usually defined as a number of bits in the key. For example, the United States government, when dealing with export control of encryption, considers any implementation of the symmetric encryption algorithm with the key length above 56 bits or its public key equivalent to be strong and thus potentially a subject to the export licensing. To be strong, an algorithm needs to have a sufficiently long key and be free of known mathematical weaknesses, as exploitation of these effectively reduces the key size. At the beginning of the 21st century, the typical security strengt
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https://en.wikipedia.org/wiki/Australian%20Science%20and%20Mathematics%20School
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The Australian Science and Mathematics School (ASMS) is a coeducational public senior high school for Years 10–12 located on the Sturt campus of Flinders University in Bedford Park, a southern suburb of Adelaide, the capital of South Australia. As the school is unzoned, it attracts students from all across the Adelaide metropolitan area as well as some regional and interstate locations, in addition to international students. The goal of the school is to prepare its students for university, particularly in the fields of mathematics and science. The ASMS is unconventional in its approach to education, emphasising a love of learning in both students and teaching staff; students are given the freedom to take control of their own education. ASMS aims to make students aware of their own learning and for them to become self-directed in the way they complete academic tasks.
Overview
The Australian Science and Mathematics School was opened in 2003 and has a total of around 380 students. As the school is designed to provide an adult environment for senior school students, there is no school uniform policy, which promotes a variety of culture and social styles and structures. A key feature of the ASMS is the productive relationship between the school and the Flinders University, on which the campus is located; the ASMS shares many resources with the university, including the library, cafeteria, student services, transport, recreational areas and car parks, in addition to booked access
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https://en.wikipedia.org/wiki/AMOLF
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AMOLF is a research institute and part of the institutes organization of the Dutch Research Council (NWO). AMOLF carries out fundamental research on the physics and design principles of natural and man-made complex matter. AMOLF uses these insights to create novel functional materials and find new solutions to societal challenges in renewable energy, green ICT and healthcare. AMOLF is located at the Amsterdam Science Park.
AMOLF used to be part of the Dutch Foundation for Fundamental Research on Matter (FOM). On 31 December 2016 FOM integrated in NWO.
History
The institute was established in 1949 by the government as the FOM Laboratory for Mass Spectrography. In 1960, it was renamed to Laboratory for Mass Separation, and in 1966 it was reorganized into a research institute and renamed FOM Institute for Atomic and Molecular Physics (AMOLF).
The original research goal was to demonstrate the separation of uranium isotopes by electromagnetic separation methods, a topic of great strategic importance after World War II. To reach this goal, a number of novel analytical instruments were developed, starting with the development of mass-spectrometric tools. In 1953 AMOLF was the first European institute to successfully enrich Uranium. Soon after, research on thermal diffusion in gases followed, as did ultracentrifuge concepts, cathode dispersion, excitation of gases by using energetic ions and research on molecular beams. The gas-ultracentrifuge developed at AMOLF (under ) provided
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https://en.wikipedia.org/wiki/Nature%20Reviews%20Microbiology
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Nature Reviews Microbiology is a monthly peer-reviewed review journal published by Nature Portfolio. It was established in 2003. The journal publishes reviews and perspectives on microbiology, bridging fundamental research and its clinical, industrial, and environmental applications. The editor-in-chief is Ashley York.
Abstracting and indexing
This journal is indexed and abstracted by the following databases:
BIOSIS Previews
Current Contents/Life Sciences
Science Citation Index
Medline
PubMed
Index Medicus
Other services that index this journal are:
Scopus , Academic Search Premier , Biotechnology Research Abstracts , CAB Abstracts , Chemical Abstracts Service, and EMBASE.
According to the Journal Citation Reports, the journal has a 2022 impact factor of 88.1, ranking it 1st out of 135 journals in the "Microbiology" category.
References
External links
Nature Research academic journals
Academic journals established in 2003
Microbiology journals
English-language journals
Monthly journals
Review journals
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https://en.wikipedia.org/wiki/Nature%20Reviews%20Genetics
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Nature Reviews Genetics is a monthly review journal published by Nature Portfolio. It was established in 2000 and covers the full breadth of modern genetics. The editor-in-chief is Linda Koch. The journal publishes review and perspective articles written by experts in the field subject to peer review and copy editing to provide authoritative coverage of topics. Each issue also contains Research Highlight articles – short summaries written by the editors that describe recent research papers.
According to the Journal Citation Reports, the journal has a 2021 impact factor of 59.943, ranking it 1st out of 175 journals in the category "Genetics & Heredity".
References
External links
Genetics journals
Nature Research academic journals
Academic journals established in 2000
Review journals
English-language journals
Monthly journals
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https://en.wikipedia.org/wiki/Michael%20E.%20Soul%C3%A9
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Michael Ellman Soulé (May 28, 1936 – June 17, 2020) was an American biologist, known for his work in promoting the idea of conservation biology.
Soulé was born in San Diego, California, the son of Berenice (Ellman) and Herman Herzoff. His father died when he was two, and he was adopted by his stepfather Alan Soulé. He earned a Ph.D. in 1964 at Stanford University in Biology under Paul R. Ehrlich, and later became Research Professor (Emeritus) in Environmental Studies, University of California, Santa Cruz. His Ph.D. thesis of 167 pages was entitled: Evolution and population phenetics of the side-blotched lizards (Uta stansburiana and its relatives) on the islands in the Gulf of California, Mexico.
Soulé was a cofounder and first president of the Society for Conservation Biology, founded in 1985. He served on the board of Round River Conservation Studies and the Wildlands Network.
Soulé co-edited with Gary Lease a book of essays titled Reinventing nature?: responses to postmodern deconstruction (1995), which was a response to the arguments presented by environmental historian William Cronon and others in Uncommon ground: toward reinventing nature (1995). He has most recently spoken out against approaches to environmental conservation that discount the value of species diversity.
References
External links
Obituary from UCSC
1936 births
2020 deaths
Writers from San Diego
20th-century American biologists
21st-century American biologists
Conservation biologists
University
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https://en.wikipedia.org/wiki/J%C3%BAlio%20C%C3%A9sar%20de%20Mello%20e%20Souza
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Júlio César de Mello e Souza (Rio de Janeiro, May 6, 1895 – Recife, June 18, 1974), was a Brazilian writer and mathematics teacher. He was well known in Brazil and abroad for his books on recreational mathematics, most of them published under the pen names of Malba Tahan and Breno de Alencar Bianco.
He wrote 69 novels and 51 books of mathematics and other subjects, with over than two million books sold by 1995. His most famous work, The Man Who Counted, saw its 54th printing in 2001.
Júlio César's most popular books, including The Man Who Counted, are collections of mathematical problems, puzzles, curiosities, and embedded in tales inspired by the Arabian Nights. He thoroughly researched his subject matters — not only the mathematics, but also the history, geography, and culture of the Islamic Empire which was the backdrop and connecting thread of his books. Yet Júlio César's travels outside Brazil were limited to short visits to Buenos Aires, Montevideo, and Lisbon: he never set foot in the deserts and cities which he so vividly described in his books.
Júlio César was very critical of the educational methods used in Brazilian classrooms, especially for mathematics. "The mathematics teacher is a sadist," he claimed, "who loves to make everything as complicated as possible." In education, he was decades ahead of his time, and his proposals are still more praised than implemented today.
For his books, Júlio César received a prize by the prestigious Brazilian Literary Acad
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https://en.wikipedia.org/wiki/Recursive%20data%20type
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In computer programming languages, a recursive data type (also known as a recursively-defined, inductively-defined or inductive data type) is a data type for values that may contain other values of the same type. Data of recursive types are usually viewed as directed graphs.
An important application of recursion in computer science is in defining dynamic data structures such as Lists and Trees. Recursive data structures can dynamically grow to an arbitrarily large size in response to runtime requirements; in contrast, a static array's size requirements must be set at compile time.
Sometimes the term "inductive data type" is used for algebraic data types which are not necessarily recursive.
Example
An example is the list type, in Haskell:
data List a = Nil | Cons a (List a)
This indicates that a list of a's is either an empty list or a cons cell containing an 'a' (the "head" of the list) and another list (the "tail").
Another example is a similar singly linked type in Java:
class List<E> {
E value;
List<E> next;
}
This indicates that non-empty list of type E contains a data member of type E, and a reference to another List object for the rest of the list (or a null reference to indicate that this is the end of the list).
Mutually recursive data types
Data types can also be defined by mutual recursion. The most important basic example of this is a tree, which can be defined mutually recursively in terms of a forest (a list of trees). Symbolically:
f: [t[1],
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https://en.wikipedia.org/wiki/Bartha%20Knoppers
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Bartha Maria Knoppers, OC OQ (born May 26, 1951) is a Canadian law Professor and an expert on the ethical aspects of genetics, genomics and biotechnology.
Born in Hilversum, Netherlands, she received a Bachelor of Arts (French and English Literature) from McMaster University (1972), a Master of Arts degree in comparative literature from the University of Alberta (1974), Bachelor of Common Law (1978) and Civil Law (1981) degrees from McGill University, where she was selected as an Executive Editor for the McGill Law Journal, a Diploma of Legal Studies from University of Cambridge (1981), and a Doctorate of Laws from the University of Paris 1 Pantheon-Sorbonne (1985). In addition, she became a member of the Quebec Bar (1985).
She was a professor at the Faculty of Law, Université de Montréal (1985-2009). Currently, she is Full Professor at the Department of Human Genetics, Faculty of Medicine, McGill University (2009-), and is an Associate Member of the Faculty of Law (2011) and the Biomedical Ethics Unit (2013). She is also the Director of the Centre of Genomics and Policy, McGill University (2009-), and the Founder and Chair of Public Population Project in Genomics (P3G) Consortium and CARTaGENE, Quebec (2003-2019).
Prof. Knoppers has held the Canada Research Chair in Law and Medicine since 2001. This involves analyzing and developing of national and international policies, laws and guidelines in the field of genomics. She is Co-Founder of the Global Alliance for Genomics
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https://en.wikipedia.org/wiki/Scientific%20classification%20%28disambiguation%29
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Scientific classification is a practice and science of categorization.
Scientific classification may also refer to:
Chemical classification
Mathematical classification, construction of subsets into a set
Statistical classification, the mathematical problem of assigning a label to an object based on a set of its attributes or features
Biology
Taxonomy (biology)
Alpha taxonomy, the science of finding, describing and naming organisms
Cladistics, a newer way of classifying organisms, based solely on phylogeny
Linnaean taxonomy, the classic scientific classification system
Virus classification, naming and sorting viruses
Astronomy
Galaxy morphological classification
Stellar classification
See also
Categorization, general
Classification of the sciences (Peirce)
Linguistic typology
Systematic name
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https://en.wikipedia.org/wiki/Krasnow%20Institute%20for%20Advanced%20Study
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The Krasnow Institute for Advanced Study brings together researchers from many disciplines to study the phenomenon known as the mind. A unit of George Mason University, the Krasnow Institute also serves as a center for doctoral education in neuroscience. Research at the institute is funded by agencies such as the National Institutes of Health, the National Science Foundation and the Department of Defense.
History
The Krasnow Institute was chartered in 1990 as a result of a bequest from Shelley Krasnow, a long-time resident of the National Capital Area. The work of the institute began in 1993 with a scientific conference, co-sponsored with The Santa Fe Institute (SFI) and hosted at George Mason University. This conference on "The Mind, the Brain, and Complex Adaptive Systems" brought together an unusual group of scientists including two Nobel laureates (Murray Gell-Mann and Herbert A. Simon) and produced new approaches to this frontier in addition to a book published by SFI.
These efforts set the institute on the path of human cognition within the context of the intersection of neuroscience, cognitive psychology and computer sciences.
Current Institute
The Krasnow Institute is home to a scientific community of 100 (many of them PhDs) most of whom are also either faculty or trainees at George Mason University. The range of their research on cognition spans from molecules to mind. The institute is housed in a dedicated facility on the Fairfax Campus of George Mason which in
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https://en.wikipedia.org/wiki/Quadrupole%20ion%20trap
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In experimental physics, a quadrupole ion trap or paul trap is a type of ion trap that uses dynamic electric fields to trap charged particles. They are also called radio frequency (RF) traps or Paul traps in honor of Wolfgang Paul, who invented the device and shared the Nobel Prize in Physics in 1989 for this work. It is used as a component of a mass spectrometer or a trapped ion quantum computer.
Overview
A charged particle, such as an atomic or molecular ion, feels a force from an electric field. It is not possible to create a static configuration of electric fields that traps the charged particle in all three directions (this restriction is known as Earnshaw's theorem). It is possible, however, to create an average confining force in all three directions by use of electric fields that change in time. To do so, the confining and anti-confining directions are switched at a rate faster than it takes the particle to escape the trap. The traps are also called "radio frequency" traps because the switching rate is often at a radio frequency.
The quadrupole is the simplest electric field geometry used in such traps, though more complicated geometries are possible for specialized devices. The electric fields are generated from electric potentials on metal electrodes. A pure quadrupole is created from hyperbolic electrodes, though cylindrical electrodes are often used for ease of fabrication. Microfabricated ion traps exist where the electrodes lie in a plane with the trapping r
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https://en.wikipedia.org/wiki/William%20A.%20Welch
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Major William Addams Welch (August 20, 1868 – May 4, 1941) was an American engineer and environmentalist who would have a major impact on the state and national park systems of the United States. Born in Cynthiana, Kentucky, he obtained a civil engineering degree from Colorado College in 1882 and a master's degree from the University of Virginia in 1886.
Background
In the 1890s, working for the U.S. government in Alaska, he assembled the first iron steamship to be built in that territory. He also designed railroads in southwest Mexico, Ecuador, Colombia and Venezuela, and worked on the legendary Madeira-Mamoré Railway in Bolivia. In 1907, yellow fever forced him to return to the U.S. where he worked for John C. and Frederick Law Olmsted.
In 1912, he was hired as assistant engineer by George W. Perkins, chairman of the newly formed Palisades Interstate Park Commission (PIP), and in 1914, he was made chief engineer and general manager. Under his leadership, Bear Mountain State Park and Harriman State Park grew from an initial to . By 1919, it was estimated that a million people a year were coming to the park. In the early 1920s, Welch's engineering work gained nationwide attention when he built Storm King Highway into the sheer cliffs above the Hudson River north of Bear Mountain.
When Welch started work on Bear Mountain State Park and Harriman State Park, there were no existing models or precedents to guide him. Welch organized a massive reforestation program, built 23 ne
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https://en.wikipedia.org/wiki/Franz%20Xaver%20Kugler
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Franz Xaver Kugler (27 November 1862 – 25 January 1929) was a German chemist, mathematician, Assyriologist, and Jesuit priest.
Kugler was born in Königsbach, Palatinate, then part of the Kingdom of Bavaria. He earned a Ph.D. in chemistry in 1885, and the following year he entered the Jesuits. By 1893 he had been ordained as a priest. Four years later at the age of 35, he became a professor of mathematics at Ignatius-College in Valkenburg in the Netherlands.
He is most noted for his studies of cuneiform tablets and Babylonian astronomy. He worked out the Babylonian theories on the Moon and planets, which were published in 1907. However his full work on Babylonian astronomy was never completed, with only three volumes out of a planned five published.
He died in Lucerne, Switzerland.
Bibliography
Die Babylonische Mondrechnung, Freiburg im Breisgau: Herder, (1900).
Die Sternenfahrt des Gilgamesch: Kosmologische Würdigung des babylonischen Nationalepos. (1904).
Sternkunde und Sterndienst in Babel. Münster in Westfalien: Aschendorffsche Verlagsbuchandlung, (1907). 2 Vols.
Volume 1
Volume 2 part 1
Volume 2, part 2.1
Volume 2, part 2.2
Supplement 1
Supplement 2 pt. 1-8
Supplement 2 pt. 9-14
Darlegungen und Thesen über altbabylonische Chronologie, Zeitschrift für Assyriologie und verwandte Gebiete, 22 (1909), pp. 63–78 (*).
GUR, masihu sa sattuk, KA, Zeitschrift für Assyriologie und verwandte Gebiete, 23 (1909), pp. 267–273
Im Bannkreis Babels: panbabylonistische K
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https://en.wikipedia.org/wiki/N400%20%28neuroscience%29
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The N400 is a component of time-locked EEG signals known as event-related potentials (ERP). It is a negative-going deflection that peaks around 400 milliseconds post-stimulus onset, although it can extend from 250-500 ms, and is typically maximal over centro-parietal electrode sites. The N400 is part of the normal brain response to words and other meaningful (or potentially meaningful) stimuli, including visual and auditory words, sign language signs, pictures, faces, environmental sounds, and smells.
History
The N400 was first discovered by Marta Kutas and Steven Hillyard in 1980. They conducted the first experiment looking at the response to unexpected words in read sentences, expecting to elicit a P300 component. The P300 had previously been shown to be elicited by unexpected stimuli. Kutas and Hillyard therefore used sentences with anomalous endings (i.e.I take coffee with cream and dog), expecting to see a P300 to the unexpected sentence-final words. However, instead of eliciting a large positivity, these anomalous endings elicited a large negativity, relative to the sentences with expected endings (i.e. He returned the book to the library) In the same paper, they confirmed that the negativity was not just caused by any unexpected event at the end of a sentence, since a semantically expected but physically unexpected word (i.e. She put on her high-heeled SHOES) elicited a P300 instead of negativity in the N400 window. This finding showed that the N400 is related to sema
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https://en.wikipedia.org/wiki/Stirling%20numbers%20of%20the%20second%20kind
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In mathematics, particularly in combinatorics, a Stirling number of the second kind (or Stirling partition number) is the number of ways to partition a set of n objects into k non-empty subsets and is denoted by or . Stirling numbers of the second kind occur in the field of mathematics called combinatorics and the study of partitions. They are named after James Stirling.
The Stirling numbers of the first and second kind can be understood as inverses of one another when viewed as triangular matrices. This article is devoted to specifics of Stirling numbers of the second kind. Identities linking the two kinds appear in the article on Stirling numbers.
Definition
The Stirling numbers of the second kind, written or or with other notations, count the number of ways to partition a set of labelled objects into nonempty unlabelled subsets. Equivalently, they count the number of different equivalence relations with precisely equivalence classes that can be defined on an element set. In fact, there is a bijection between the set of partitions and the set of equivalence relations on a given set. Obviously,
for n ≥ 0, and for n ≥ 1,
as the only way to partition an n-element set into n parts is to put each element of the set into its own part, and the only way to partition a nonempty set into one part is to put all of the elements in the same part. Unlike Stirling numbers of the first kind, they can be calculated using a one-sum formula:
The Stirling numbers of the secon
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https://en.wikipedia.org/wiki/Stirling%20numbers%20of%20the%20first%20kind
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In mathematics, especially in combinatorics, Stirling numbers of the first kind arise in the study of permutations. In particular, the Stirling numbers of the first kind count permutations according to their number of cycles (counting fixed points as cycles of length one).
The Stirling numbers of the first and second kind can be understood as inverses of one another when viewed as triangular matrices. This article is devoted to specifics of Stirling numbers of the first kind. Identities linking the two kinds appear in the article on Stirling numbers.
Definitions
Stirling numbers of the first kind are the coefficients in the expansion of the falling factorial
into powers of the variable :
For example, , leading to the values , , and .
Subsequently, it was discovered that the absolute values of these numbers are equal to the number of permutations of certain kinds. These absolute values, which are known as unsigned Stirling numbers of the first kind, are often denoted or . They may be defined directly to be the number of permutations of elements with disjoint cycles. For example, of the permutations of three elements, there is one permutation with three cycles (the identity permutation, given in one-line notation by or in cycle notation by ), three permutations with two cycles (, , and ) and two permutations with one cycle ( and ). Thus, , and . These can be seen to agree with the previous calculation of for .
It was observed by Alfréd Rényi that the unsigne
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https://en.wikipedia.org/wiki/Fr%C3%B6licher%20space
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In mathematics, Frölicher spaces extend the notions of calculus and smooth manifolds. They were introduced in 1982 by the mathematician Alfred Frölicher.
Definition
A Frölicher space consists of a non-empty set X together with a subset C of Hom(R, X) called the set of smooth curves, and a subset F of Hom(X, R) called the set of smooth real functions, such that for each real function
f : X → R
in F and each curve
c : R → X
in C, the following axioms are satisfied:
f in F if and only if for each γ in C, f . γ in C∞(R, R)
c in C if and only if for each φ in F, φ . c in C∞(R, R)
Let A and B be two Frölicher spaces. A map
m : A → B
is called smooth if for each smooth curve c in CA, m.c is in CB. Furthermore, the space of all such smooth maps has itself the structure of a Frölicher space. The smooth functions on
C∞(A, B)
are the images of
References
, section 23
Smooth functions
Structures on manifolds
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https://en.wikipedia.org/wiki/Aluminate
|
In chemistry, an aluminate is a compound containing an oxyanion of aluminium, such as sodium aluminate. In the naming of inorganic compounds, it is a suffix that indicates a polyatomic anion with a central aluminium atom.
Aluminate oxyanions
Aluminium oxide (alumina) is amphoteric: it dissolves in both bases and acids. When dissolved in bases it forms hydroxyaluminate ions in the same way as aluminium hydroxide or aluminium salts. The hydroxyaluminate or hydrated aluminate can be precipitated and then calcined to produce anhydrous aluminates. Aluminates are often formulated as a combination of basic oxide and aluminium oxide, for example the formula of anhydrous sodium aluminate NaAlO2 would be shown as Na2O·Al2O3.
A number of aluminate oxyanions are known:
The simplest is the approximately tetrahedral found in the compound Na5AlO4,
framework ions in anhydrous sodium aluminate NaAlO2 and monocalcium aluminate, CaAl2O4 made up of corner-sharing {AlO4} tetrahedra.
A ring anion, the cyclic anion, found in tricalcium aluminate, Ca3Al2O6, which can be considered to consist of 6 corner sharing {AlO4} tetrahedra.
A number of infinite chain anions in the compounds Na7Al3O8 which contains rings linked to form chains, Na7Al13O10 and Na17Al5O16 which contain discrete chain anions.
Mixed oxides containing aluminium
There are many mixed oxides containing aluminium where there are no discrete or polymeric aluminate ions. The spinels with a generic formula that contain alumini
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https://en.wikipedia.org/wiki/Michael%20Gazzaniga
|
Michael S. Gazzaniga (born December 12, 1939) is a professor of psychology at the University of California, Santa Barbara in the USA, where he heads the new SAGE Center for the Study of the Mind. He is one of the leading researchers in cognitive neuroscience, the study of the neural basis of mind. He is a member of the American Academy of Arts & Sciences, the Institute of Medicine, and the National Academy of Sciences.
Biography
In 1961, Gazzaniga graduated from Dartmouth College in the USA. In 1964, he received a Ph.D. in psychobiology from the California Institute of Technology, where he worked under the guidance of Roger Sperry (who had primary responsibilities for initiating human split-brain research). In his subsequent work he has made important advances in our understanding of functional lateralization in the brain and how the cerebral hemispheres communicate with one another.
Gazzaniga's publication career includes books for a general audience such as The Social Brain, Mind Matters, Nature's Mind, The Ethical Brain and Who's in Charge?. He is also the editor of The Cognitive Neurosciences book series published by the MIT Press, which features the work of nearly 200 scientists and is a sourcebook for the field. His latest monograph is entitled Who's in Charge?: Free Will and the Science of the Brain. It was published by HarperCollins in 2011.
Gazzaniga founded the Centers for Cognitive Neuroscience at the University of California, Davis and at Dartmouth College, th
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https://en.wikipedia.org/wiki/Charles%20Elachi
|
Charles Elachi (born April 18, 1947) is a Lebanese-American professor (emeritus) of electrical engineering and planetary science at the California Institute of Technology (Caltech). From 2001 to 2016 he was the 8th director of the Jet Propulsion Laboratory and vice president of Caltech.
Early life and education
Elachi was born in Lebanon. He studied at Collège des Apôtres, Jounieh from 1958 to 1962, and then at the École Orientale, Zahlé, where he graduated in 1964 first in Lebanon in the Lebanese Baccalaureate (Mathématiques Élémentaires).
Elachi received a bachelor's degree (1968) in physics from Joseph Fourier University, Grenoble, France; a first master's degree (Diplôme d'Ingénieur - 1968) in engineering from Grenoble Institute of Technology; and a second master's degree (1969) and doctorate (1971) in electrical sciences from the California Institute of Technology, Pasadena. He also has a master's degree (1983) in geology from the University of California, Los Angeles, and an MBA (1979) from the University of Southern California. He joined JPL in 1970.
Career
During his 16-year tenure as JPL's director, 24 missions managed by the laboratory were launched: Genesis, Jason 1 and Mars Odyssey (2001); GRACE (2002); Galaxy Evolution Explorer, Mars Exploration Rovers Spirit and Opportunity, Spitzer Space Telescope (2003); Deep Impact and Mars Reconnaissance Orbiter (2005); Cloudsat (2006); Dawn and Mars Phoenix lander (2007); Jason 2 (2008); Kepler and Wide-field Infrared S
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https://en.wikipedia.org/wiki/Characteristic%20energy%20length%20scale
|
The characteristic energy length scale describes the size of the region from which energy flows to a rapidly moving crack. If material properties change within the characteristic energy length scale, local wave speeds can dominate crack dynamics. This can lead to supersonic fracture.
Materials science
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https://en.wikipedia.org/wiki/Universally%20measurable%20set
|
In mathematics, a subset of a Polish space is universally measurable if it is measurable with respect to every complete probability measure on that measures all Borel subsets of . In particular, a universally measurable set of reals is necessarily Lebesgue measurable (see below).
Every analytic set is universally measurable. It follows from projective determinacy, which in turn follows from sufficient large cardinals, that every projective set is universally measurable.
Finiteness condition
The condition that the measure be a probability measure; that is, that the measure of itself be 1, is less restrictive than it may appear. For example, Lebesgue measure on the reals is not a probability measure, yet every universally measurable set is Lebesgue measurable. To see this, divide the real line into countably many intervals of length 1; say, N0=[0,1), N1=[1,2), N2=[-1,0), N3=[2,3), N4=[-2,-1), and so on. Now letting μ be Lebesgue measure, define a new measure ν by
Then easily ν is a probability measure on the reals, and a set is ν-measurable if and only if it is Lebesgue measurable. More generally a universally measurable set must be measurable with respect to every sigma-finite measure that measures all Borel sets.
Example contrasting with Lebesgue measurability
Suppose is a subset of Cantor space ; that is, is a set of infinite sequences of zeroes and ones. By putting a binary point before such a sequence, the sequence can be viewed as a real number between 0
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https://en.wikipedia.org/wiki/Distribution%20ensemble
|
In cryptography, a distribution ensemble or probability ensemble is a family of distributions or random variables where is a (countable) index set, and each is a random variable, or probability distribution. Often and it is required that each have a certain property for n sufficiently large.
For example, a uniform ensemble is a distribution ensemble where each is uniformly distributed over strings of length n. In fact, many applications of probability ensembles implicitly assume that the probability spaces for the random variables all coincide in this way, so every probability ensemble is also a stochastic process.
See also
Provable security
Statistically close
Pseudorandom ensemble
Computational indistinguishability
References
Goldreich, Oded (2001). Foundations of Cryptography: Volume 1, Basic Tools. Cambridge University Press. . Fragments available at the author's web site.
Theory of cryptography
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https://en.wikipedia.org/wiki/Pseudorandom%20ensemble
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In cryptography, a pseudorandom ensemble is a family of variables meeting the following criteria:
Let be a uniform ensemble
and be an ensemble. The ensemble is called pseudorandom if and
are indistinguishable in polynomial time.
References
Goldreich, Oded (2001). Foundations of Cryptography: Volume 1, Basic Tools. Cambridge University Press. . Fragments available at the author's web site.
Algorithmic information theory
Pseudorandomness
Cryptography
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https://en.wikipedia.org/wiki/Spawn
|
Spawn or spawning may refer to:
Spawn (biology), the eggs and sperm of aquatic animals
Arts, entertainment, and media
Spawn (character), a fictional character in the comic series of the same name and in the associated franchise
Spawn: Armageddon, a 2003 video game based on the comic series for sixth generation consoles
Spawn: In the Demon's Hand, a 1999 arcade game based on the comic series
Spawn (1997 film), a cinema adaptation of the comic series
Spawn (1999 video game), a video game for the Game Boy Color
Spawn (upcoming film), an upcoming American superhero film
Spawn: Godslayer, a spin-off comic series
Todd McFarlane's Spawn (also known as Spawn: The Animated Series), an American adult animation television series which aired on HBO from 1997 through 1999
Spawn (novel), a 1983 horror novel by Shaun Hutson
Spawn, a 1993 album by Rise Robots Rise
"Spawn Again", a song on the 1999 album Neon Ballroom by Silverchair
Spawn (Again): A Tribute to Silverchair, a 2017 compilation album by various UNFD artists
Spawning (video games), the in-game creation or re-creation of an entity
Other uses
Spawn (computing), a function that executes a child process
SPAWN (Salmon Protection and Watershed Network), a project of the Turtle Island Restoration Network (TIRN), a United States 501(c)(3) nonprofit environmental organization
Spawning bed, an installation used in fishery management to increase fish reproduction
Spawning networks, a type of computer network
See also
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https://en.wikipedia.org/wiki/Carl%20Hagen
|
Carl Hagen may refer to:
Carl I. Hagen (born 1944), Norwegian politician
Carl Fredrik Hagen (born 1991), Norwegian cyclist
Carl Heinrich Hagen (1785–1856), jurist, socio-economist and government official
C. R. Hagen (born 1937), professor of particle physics
See also
Karl Gottfried Hagen (1749–1829), German chemist
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https://en.wikipedia.org/wiki/Basic%20hypergeometric%20series
|
In mathematics, basic hypergeometric series, or q-hypergeometric series, are q-analogue generalizations of generalized hypergeometric series, and are in turn generalized by elliptic hypergeometric series.
A series xn is called hypergeometric if the ratio of successive terms xn+1/xn is a rational function of n. If the ratio of successive terms is a rational function of qn, then the series is called a basic hypergeometric series. The number q is called the base.
The basic hypergeometric series was first considered by . It becomes the hypergeometric series in the limit when base .
Definition
There are two forms of basic hypergeometric series, the unilateral basic hypergeometric series φ, and the more general bilateral basic hypergeometric series ψ.
The unilateral basic hypergeometric series is defined as
where
and
is the q-shifted factorial.
The most important special case is when j = k + 1, when it becomes
This series is called balanced if a1 ... ak + 1 = b1 ...bkq.
This series is called well poised if a1q = a2b1 = ... = ak + 1bk, and very well poised if in addition a2 = −a3 = qa11/2.
The unilateral basic hypergeometric series is a q-analog of the hypergeometric series since
holds ().
The bilateral basic hypergeometric series, corresponding to the bilateral hypergeometric series, is defined as
The most important special case is when j = k, when it becomes
The unilateral series can be obtained as a special case of the bilateral one by setting one of the b var
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https://en.wikipedia.org/wiki/MOPAC
|
MOPAC is a popular computer program used in computational chemistry. It is designed to implement semi-empirical quantum chemistry algorithms, and it runs on Windows, Mac, and Linux.
MOPAC2016 is the current version. MOPAC2016 is able to perform calculations on small molecules and enzymes using PM7, PM6, PM3, AM1, MNDO, and RM1. The Sparkle model (for lanthanide chemistry) is also available. Academic users can use this program for free, whereas government and commercial users must purchase the software.
MOPAC was largely written by Michael Dewar's research group at the University of Texas at Austin. Its name is derived from Molecular Orbital PACkage, and it is also a pun on the Mopac Expressway that runs around Austin.
MOPAC2007 included the new Sparkle/AM1, Sparkle/PM3, RM1 and PM6 models, with an increased emphasis on solid state capabilities. However, it does not have yet MINDO/3, PM5, analytical derivatives, the Tomasi solvation model and intersystem crossing. MOPAC2007 was followed by the release of MOPAC2009 in 2008 which presents many improved features
The latest versions are no longer public domain software as were the earlier versions such as MOPAC6 and MOPAC7. However, there are recent efforts to keep MOPAC7 working as open source software. An open source version of MOPAC7 for Linux is also available. The author of MOPAC, James Stewart, released in 2006 a public domain version of MOPAC7 entirely written in Fortran 90 called MOPAC7.1.
See also
Semi-empirical qua
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https://en.wikipedia.org/wiki/Richard%20Rusczyk
|
Richard Rusczyk (; ; born September 21, 1971) is the founder and chief executive officer of Art of Problem Solving Inc. (as well as the website, which serves as a mathematics forum and place to hold online classes) and a co-author of the Art of Problem Solving textbooks. Rusczyk was a national Mathcounts participant in 1985, and he won the USA Math Olympiad (USAMO) in 1989. He is one of the co-creators of the Mandelbrot Competition, and the director of the USA Mathematical Talent Search (USAMTS). He also founded the San Diego Math Circle.
Early life
Richard Rusczyk was born in Idaho Falls, Idaho in 1971. He signed up for the MathCounts program when he was in middle school. As a high schooler, Rusczyk was a part of his high school math team and took part in the American Mathematics Competitions. Rusczyk would later go on to attend Princeton University, which he graduated from in 1993.
Art of Problem Solving
In 1994, Rusczyk and Sandor Lehoczky wrote the Art of Problem Solving books, designed to prepare students for mathematical competitions by teaching them concepts and problem-solving methods rarely taught in school. These books lent their name to the company he founded in 2003.
After working for four years as a bond trader for D. E. Shaw & Co., Rusczyk created the Art of Problem Solving website, which provides resources for middle and high school students to develop their mathematics and problem-solving abilities. These include real-time competitions to solve math prob
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https://en.wikipedia.org/wiki/Vatican%20Advanced%20Technology%20Telescope
|
The Alice P. Lennon Telescope and its Thomas J. Bannan Astrophysics Facility, known together as the Vatican Advanced Technology Telescope (VATT), is a Gregorian telescope observing in the optical and infrared situated on Mount Graham in southeast Arizona, United States. Measuring wide, the telescope achieved its first light in 1993.
VATT is part of the Mount Graham International Observatory and is operated by the Vatican Observatory, one of the oldest astronomical research institutions in the world, in partnership with The University of Arizona.
Design
The heart of the telescope is an f/1.0 honeycombed construction, borosilicate primary mirror. The VATT's mirror is unusually 'fast' at f/1, which means that its focal distance is equal to its diameter. Because it has such a short focal length, a Gregorian design could be employed which uses a concave secondary mirror at a point beyond the primary focus; this allows unusually sharp focusing across the field of view.
The unusual optical design and novel mirror fabrication techniques mean that both the primary and secondary mirrors are among the most exact surfaces ever made for a ground-based telescope. In addition, the skies above Mount Graham are among the most clear, steady, and dark in the continental North America. Seeing of better than one arc-second even without adaptive optics can be achieved on a regular basis.
Construction
The primary mirror was manufactured at The University of Arizona's Steward Observatory Mi
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https://en.wikipedia.org/wiki/Execute%20in%20place
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In computer science, execute in place (XIP) is a method of executing programs directly from long-term storage rather than copying it into RAM. It is an extension of using shared memory to reduce the total amount of memory required.
Its general effect is that the program text consumes no writable memory, saving it for dynamic data, and that all instances of the program are run from a single copy.
For this to work, several criteria have to be met:
The storage must provide a similar interface to the CPU as regular memory (or an adaptive layer must be present).
This interface must provide sufficiently fast read operations with a random access pattern.
The file system, if one is used, needs to expose appropriate mapping functions.
The program must either be linked to be aware of the address the storage appears at in the system or be position-independent.
The program must not modify data within the loaded image.
The storage requirements are usually met by using NOR flash memory or EEPROM, which can be addressed as individual words for read operations, although it is a bit slower than normal system RAM in most setups.
XIP during boot load
Typically, the First Stage Boot Loader is an XIP program that is linked to run at the address at which the flash chip(s) are mapped at power-up and contains a minimal program to set up the system RAM (which depends on the components used on the individual boards and cannot be generalized enough so that the proper sequence could be embedded
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https://en.wikipedia.org/wiki/Data%20%28computer%20science%29
|
In computer science, data (treated as singular, plural, or as a mass noun) is any sequence of one or more symbols; datum is a single symbol of data. Data requires interpretation to become information. Digital data is data that is represented using the binary number system of ones (1) and zeros (0), instead of analog representation. In modern (post-1960) computer systems, all data is digital.
Data exists in three states: data at rest, data in transit and data in use. Data within a computer, in most cases, moves as parallel data. Data moving to or from a computer, in most cases, moves as serial data. Data sourced from an analog device, such as a temperature sensor, may be converted to digital using an analog-to-digital converter. Data representing quantities, characters, or symbols on which operations are performed by a computer are stored and recorded on magnetic, optical, electronic, or mechanical recording media, and transmitted in the form of digital electrical or optical signals. Data pass in and out of computers via peripheral devices.
Physical computer memory elements consist of an address and a byte/word of data storage. Digital data are often stored in relational databases, like tables or SQL databases, and can generally be represented as abstract key/value pairs. Data can be organized in many different types of data structures, including arrays, graphs, and objects. Data structures can store data of many different types, including 01677877777, strings and even othe
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https://en.wikipedia.org/wiki/Monkey%20and%20hunter
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In physics, The Monkey and the Hunter is a hypothetical scenario often used to illustrate the effect of gravity on projectile motion. It can be presented as exercise problem or as a demonstration. No live monkeys are used in the demonstrations.
The essentials of the problem are stated in many introductory guides to physics. In essence, the problem is as follows: A hunter with a blowgun goes out in the woods to hunt for monkeys and sees one hanging in a tree. The monkey releases its grip the instant the hunter fires his blowgun. Where should the hunter aim in order to hit the monkey?
Discussion
To answer this question, recall that according to Galileo's law, all objects fall with the same constant acceleration of gravity (about 9.8 metres per second per second near the Earth's surface), regardless of the object's weight. Furthermore, horizontal motions and vertical motions are independent: gravity acts only upon an object's vertical velocity, not upon its velocity in the horizontal direction. The hunter's dart, therefore, falls with the same acceleration as the monkey.
Assume for the moment that gravity was not at work. In that case, the dart would proceed in a straight-line trajectory at a constant speed (Newton's first law). Gravity causes the dart to fall away from this straight-line path, making a trajectory that is in fact a parabola. Now, consider what happens if the hunter aims directly at the monkey, and the monkey releases his grip the instant the hunter
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https://en.wikipedia.org/wiki/MNDO
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MNDO, or Modified Neglect of Diatomic Overlap is a semi-empirical method for the quantum calculation of molecular electronic structure in computational chemistry. It is based on the Neglect of Diatomic Differential Overlap integral approximation. Similarly, this method replaced the earlier MINDO method. It is part of the MOPAC program and was developed in the group of Michael Dewar. It is also part of the AMPAC, GAMESS (US), PC GAMESS, GAMESS (UK), Gaussian, ORCA and CP2K programs.
Later, it was essentially replaced by two new methods, PM3 and AM1, which are similar but have different parameterisation methods.
The extension by W. Thiel's group, called MNDO/d, which adds d functions, is widely used for organometallic compounds. It is included in GAMESS (UK).
MNDOC, also from W. Thiel's group, explicitly adds correlation effects though second order perturbation theory with the parameters fitted to experiment from the correlated calculation. In this way, the method should give better results for systems where correlation is particularly important and different from that in the ground state molecules from the MNDO training set. This include excited states and transition states. However Cramer (see reference below) argues that "the model has not been compared to other NDDO models to the degree necessary to evaluate whether the formalism lives up to that potential.
References
MNDO
MNDO/d
MNDOC
Semiempirical quantum chemistry methods
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https://en.wikipedia.org/wiki/Austin%20Model%201
|
Austin Model 1, or AM1, is a semi-empirical method for the quantum calculation of molecular electronic structure in computational chemistry. It is based on the Neglect of Differential Diatomic Overlap integral approximation. Specifically, it is a generalization of the modified neglect of differential diatomic overlap approximation. Related methods are PM3 and the older MINDO.
AM1 was developed by Michael Dewar and co-workers and published in 1985. AM1 is an attempt to improve the MNDO model by reducing the repulsion of atoms at close separation distances. The atomic core-atomic core terms in the MNDO equations were modified through the addition of off-center attractive and repulsive Gaussian functions.
The complexity of the parameterization problem increased in AM1 as the number of parameters per atom increased from 7 in MNDO to 13-16 per atom in AM1.
The results of AM1 calculations are sometimes used as the starting points for parameterizations of forcefields in molecular modelling.
AM1 is implemented in the MOPAC, AMPAC, Gaussian, CP2K, GAMESS (US), PC GAMESS, GAMESS (UK), and SPARTAN programs.
An extension of AM1 is SemiChem Austin Model 1 (SAM1), which is implemented in the AMPAC program and which explicitly treats d-orbitals.
An extension of AM1 is AM1* that is available in VAMP software.
See also
Semi-empirical quantum chemistry methods
Notes
References
Semiempirical quantum chemistry methods
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https://en.wikipedia.org/wiki/PM3%20%28chemistry%29
|
PM3, or Parametric Method 3, is a semi-empirical method for the quantum calculation of molecular electronic structure in computational chemistry. It is based on the Neglect of Differential Diatomic Overlap integral approximation.
The PM3 method uses the same formalism and equations as the AM1 method. The only differences are:
1) PM3 uses two Gaussian functions for the core repulsion function, instead of the variable number used by AM1 (which uses between one and four Gaussians per element);
2) the numerical values of the parameters are different. The other differences lie in the philosophy and methodology used during the parameterization: whereas AM1 takes some of the parameter values from spectroscopical measurements, PM3 treats them as optimizable values.
The method was developed by J. J. P. Stewart and first published in 1989. It is implemented in the MOPAC program (of which the older versions are public domain), along with the related RM1, AM1, MNDO and MINDO methods, and in several other programs such as Gaussian, CP2K, GAMESS (US), GAMESS (UK), PC GAMESS, Chem3D, AMPAC, ArgusLab, BOSS, and SPARTAN.
The original PM3 publication included parameters for the following elements: H, C, N, O, F, Al, Si, P, S, Cl, Br, and I.
The PM3 implementation in the SPARTAN program includes PM3tm with additional extensions for transition metals supporting calculations on Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, Tc, Ru, Rh, Pd, Hf, Ta, W, Re, Os, Ir, Pt, and Gd. Many other e
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https://en.wikipedia.org/wiki/First%20Law
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"First Law" is a science fiction short story by American writer Isaac Asimov, first published in the October 1956 issue of Fantastic Universe magazine and later collected in The Rest of the Robots (1964) and The Complete Robot (1982). The title of the story is a reference to the first of the Three Laws of Robotics.
Background
In 1941 John W. Campbell of Astounding Science Fiction began a new department, "Probability Zero", for very short stories. He hoped to publish new writers, but wanted experienced authors early on, including Isaac Asimov. To Asimov's surprise, Campbell rejected "Big Game" and "First Law" in November and December 1941. Having learned that a rejected story might sell elsewhere, he saved "First Law" until it was published by Fantastic Universe in October 1956.
Plot summary
The story is very short, only three pages in length, and takes the form of Mike Donovan's account of an incident that occurred on Titan, one of Saturn's moons. He tells of a malfunctioning robot named Emma that escaped from the base and was later encountered by Donovan while he was lost during a storm. While Donovan's life was in danger, Emma chose to protect its offspring, a small robot that it had built, instead of assisting him. This was a direct violation of the First Law of Robotics, which states that "a robot may not injure a human being, or through inaction allow a human being to come to harm". Apparently, maternal instincts in the robot took precedence over its programming.
Wh
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https://en.wikipedia.org/wiki/Octahedral%20molecular%20geometry
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In chemistry, octahedral molecular geometry, also called square bipyramidal, describes the shape of compounds with six atoms or groups of atoms or ligands symmetrically arranged around a central atom, defining the vertices of an octahedron. The octahedron has eight faces, hence the prefix octa. The octahedron is one of the Platonic solids, although octahedral molecules typically have an atom in their centre and no bonds between the ligand atoms. A perfect octahedron belongs to the point group Oh. Examples of octahedral compounds are sulfur hexafluoride SF6 and molybdenum hexacarbonyl Mo(CO)6. The term "octahedral" is used somewhat loosely by chemists, focusing on the geometry of the bonds to the central atom and not considering differences among the ligands themselves. For example, , which is not octahedral in the mathematical sense due to the orientation of the bonds, is referred to as octahedral.
The concept of octahedral coordination geometry was developed by Alfred Werner to explain the stoichiometries and isomerism in coordination compounds. His insight allowed chemists to rationalize the number of isomers of coordination compounds. Octahedral transition-metal complexes containing amines and simple anions are often referred to as Werner-type complexes.
Isomerism in octahedral complexes
When two or more types of ligands (La, Lb, ...) are coordinated to an octahedral metal centre (M), the complex can exist as isomers. The naming system for these isomers depends upon t
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https://en.wikipedia.org/wiki/Neuron%20%28journal%29
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Neuron is a biweekly peer-reviewed scientific journal published by Cell Press, an imprint of Elsevier. Established in 1988, it covers neuroscience and related biological processes.
The current editor in chief is Mariela Zirlinger. The founding editors were Lily Jan, A. James Hudspeth, Louis Reichardt, Roger Nicoll, and Zach Hall. A past Editor in Chief was Katja Brose.
References
External links
Neuroscience journals
Cell Press academic journals
Academic journals established in 1988
English-language journals
Biweekly journals
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https://en.wikipedia.org/wiki/Cohesion%20%28chemistry%29
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In chemistry and physics, cohesion (), also called cohesive attraction or cohesive force, is the action or property of like molecules sticking together, being mutually attractive. It is an intrinsic property of a substance that is caused by the shape and structure of its molecules, which makes the distribution of surrounding electrons irregular when molecules get close to one another, creating electrical attraction that can maintain a microscopic structure such as a water drop. Cohesion allows for surface tension, creating a "solid-like" state upon which light-weight or low-density materials can be placed.
Water, for example, is strongly cohesive as each molecule may make four hydrogen bonds to other water molecules in a tetrahedral configuration. This results in a relatively strong Coulomb force between molecules. In simple terms, the polarity (a state in which a molecule is oppositely charged on its poles) of water molecules allows them to be attracted to each other. The polarity is due to the electronegativity of the atom of oxygen: oxygen is more electronegative than the atoms of hydrogen, so the electrons they share through the covalent bonds are more often close to oxygen rather than hydrogen. These are called polar covalent bonds, covalent bonds between atoms that thus become oppositely charged. In the case of a water molecule, the hydrogen atoms carry positive charges while the oxygen atom has a negative charge. This charge polarization within the molecule allows it
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https://en.wikipedia.org/wiki/Exponential%20object
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In mathematics, specifically in category theory, an exponential object or map object is the categorical generalization of a function space in set theory. Categories with all finite products and exponential objects are called cartesian closed categories. Categories (such as subcategories of Top) without adjoined products may still have an exponential law.
Definition
Let be a category, let and be objects of , and let have all binary products with . An object together with a morphism is an exponential object if for any object and morphism there is a unique morphism (called the transpose of ) such that the following diagram commutes:
This assignment of a unique to each establishes an isomorphism (bijection) of hom-sets,
If exists for all objects in , then the functor defined on objects by and on arrows by , is a right adjoint to the product functor . For this reason, the morphisms and are sometimes called exponential adjoints of one another.
Equational definition
Alternatively, the exponential object may be defined through equations:
Existence of is guaranteed by existence of the operation .
Commutativity of the diagrams above is guaranteed by the equality .
Uniqueness of is guaranteed by the equality .
Universal property
The exponential is given by a universal morphism from the product functor to the object . This universal morphism consists of an object and a morphism .
Examples
In the category of sets, an exponential object is the set of a
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https://en.wikipedia.org/wiki/Trimethyl%20borate
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Trimethyl borate is the organoboron compound with the formula B(OCH3)3. It is a colourless liquid that burns with a green flame. It is an intermediate in the preparation of sodium borohydride and is a popular reagent in organic chemistry. It is a weak Lewis acid (AN = 23, Gutmann-Beckett method).
Borate esters are prepared by heating boric acid or related boron oxides with alcohols under conditions where water is removed.
Applications
Trimethyl borate is the main precursor to sodium borohydride by its reaction with sodium hydride:
4 NaH + B(OCH3)3 → NaBH4 + 3 NaOCH3
It is a gaseous anti-oxidant in brazing and solder flux. Otherwise, trimethyl borate has no announced commercial applications. It has been explored as a fire retardant, as well as being examined as an additive to some polymers.
Organic synthesis
It is a useful reagent in organic synthesis, as a precursor to boronic acids, which are used in Suzuki couplings. These boronic acids are prepared via reaction of the trimethyl borate with Grignard reagents followed by hydrolysis:.
ArMgBr + B(OCH3)3 → MgBrOCH3 + ArB(OCH3)2
ArB(OCH3)2 + 2 H2O → ArB(OH)2 + 2 HOCH3
References
External links
National Pollutant Inventory - Boron and compounds
MSDS for Trimethyl Borate
WebBook page for BC3H9O3
Methyl esters
Borate esters
Solvents
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https://en.wikipedia.org/wiki/Erik%20Trinkaus
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Erik Trinkaus (born December 24, 1948) is a paleoanthropologist specializing in Neandertal and early modern human biology and human evolution. Trinkaus researches the evolution of the species Homo sapiens and recent human diversity, focusing on the paleoanthropology and emergence of late archaic and early modern humans, and the subsequent evolution of anatomically modern humanity. Trinkaus is a member of the National Academy of Sciences, and the Mary Tileston Hemenway Professor Emeritus of Arts and Sciences at Washington University in St. Louis. He is a frequent contributor to publications such as Science, Proceedings of the National Academy of Sciences, PLOS One, American Journal of Physical Anthropology, and the Journal of Human Evolution and has written/co-written or edited/co-edited fifteen books in paleoanthropology. He is frequently quoted in the popular media.
Education
Trinkaus received his Bachelor of Arts degree in Art History from the University of Wisconsin–Madison (1970), and his master's and PhD degrees in Anthropology from the University of Pennsylvania, the latter in 1975.
Scientific views
Trinkaus has been concerned primarily with the biology and behavior of Neandertals and early modern humans through the Middle and Late Pleistocene, in order to shed light on these past humans and to understand the emergence and establishment of modern humans. His work therefore has been primarily concerned with the comparative and functional anatomy, paleopathology, and
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https://en.wikipedia.org/wiki/Association%20scheme
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The theory of association schemes arose in statistics, in the theory of experimental design for the analysis of variance. In mathematics, association schemes belong to both algebra and combinatorics. In algebraic combinatorics, association schemes provide a unified approach to many topics, for example combinatorial designs and the theory of error-correcting codes. In algebra, association schemes generalize groups, and the theory of association schemes generalizes the character theory of linear representations of groups.
Definition
An n-class association scheme consists of a set X together with a partition S of X × X into n + 1 binary relations, R0, R1, ..., Rn which satisfy:
; it is called the identity relation.
Defining , if R in S, then R* in S.
If , the number of such that and is a constant depending on , , but not on the particular choice of and .
An association scheme is commutative if for all , and . Most authors assume this property.
A symmetric association scheme is one in which each is a symmetric relation. That is:
if (x, y) ∈ Ri, then (y, x) ∈ Ri. (Or equivalently, R* = R.)
Every symmetric association scheme is commutative.
Note, however, that while the notion of an association scheme generalizes the notion of a group, the notion of a commutative association scheme only generalizes the notion of a commutative group.
Two points x and y are called i th associates if . The definition states that if x and y are i th associates then so are y and x.
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https://en.wikipedia.org/wiki/Gang%20scheduling
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In computer science, gang scheduling is a scheduling algorithm for parallel systems that schedules related threads or processes to run simultaneously on different processors. Usually these will be threads all belonging to the same process, but they may also be from different processes, where the processes could have a producer-consumer relationship or come from the same MPI program.
Gang scheduling is used to ensure that if two or more threads or processes communicate with each other, they will all be ready to communicate at the same time. If they were not gang-scheduled, then one could wait to send or receive a message to another while it is sleeping, and vice versa. When processors are over-subscribed and gang scheduling is not used within a group of processes or threads which communicate with each other, each communication event could suffer the overhead of a context switch.
Gang scheduling is based on a data structure called the Ousterhout matrix. In this matrix each row represents a time slice, and each column a processor. The threads or processes of each job are packed into a single row of the matrix. During execution, coordinated context switching is performed across all nodes to switch from the processes in one row to those in the next row.
Gang scheduling is stricter than coscheduling. It requires all threads of the same process to run concurrently, while coscheduling allows for fragments, which are sets of threads that do not run concurrently with the rest of the
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https://en.wikipedia.org/wiki/Mathematical%20Tripos
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The Mathematical Tripos is the mathematics course that is taught in the Faculty of Mathematics at the University of Cambridge. It is the oldest Tripos examined at the university.
Origin
In its classical nineteenth-century form, the tripos was a distinctive written examination of undergraduate students of the University of Cambridge. Prior to 1824, the Mathematical Tripos was formally known as the "Senate House Examination". From about 1780 to 1909, the "Old Tripos" was distinguished by a number of features, including the publication of an order of merit of successful candidates, and the difficulty of the mathematical problems set for solution. By way of example, in 1854, the Tripos consisted of 16 papers spread over eight days, totaling 44.5 hours. The total number of questions was 211. It was divided into two parts, with Part I (the first three days) covering more elementary topics.
The actual marks for the exams were never published, but there is reference to an exam in the 1860s where, out of a total possible mark of 17,000, the senior wrangler achieved 7634, the second wrangler 4123, the lowest wrangler around 1500 and the lowest scoring candidate obtaining honours (the wooden spoon) 237; about 100 candidates were awarded honours. The 300-odd candidates below that level did not earn honours and were known as poll men. The questions for the 1841 examination may be found within Cambridge University Magazine (pages 191–208).
Influence
According to the study Masters of The
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https://en.wikipedia.org/wiki/Deep%20inelastic%20scattering
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In particle physics, deep inelastic scattering is the name given to a process used to probe the insides of hadrons (particularly the baryons, such as protons and neutrons), using electrons, muons and neutrinos. It was first attempted in the 1960s and 1970s and provided the first convincing evidence of the reality of quarks, which up until that point had been considered by many to be a purely mathematical phenomenon. It is an extension of Rutherford scattering to much higher energies of the scattering particle and thus to much finer resolution of the components of the nuclei.
Henry Way Kendall, Jerome Isaac Friedman and Richard E. Taylor were joint recipients of the Nobel Prize of 1990 "for their pioneering investigations concerning deep inelastic scattering of electrons on protons and bound neutrons, which have been of essential importance for the development of the quark model in particle physics."
Description
To explain each part of the terminology, "scattering" refers to the lepton's (electron, muon, etc.) deflection. Measuring the angles of deflection gives information about the nature of the process. "Inelastic" means that the target absorbs some kinetic energy. In fact, at the very high energies of leptons used, the target is "shattered" and emits many new particles. These particles are hadrons and, to oversimplify greatly, the process is interpreted as a constituent quark of the target being "knocked out" of the target hadron, and due to quark confinement, the quar
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https://en.wikipedia.org/wiki/Generalized%20arithmetic%20progression
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In mathematics, a generalized arithmetic progression (or multiple arithmetic progression) is a generalization of an arithmetic progression equipped with multiple common differences – whereas an arithmetic progression is generated by a single common difference, a generalized arithmetic progression can be generated by multiple common differences. For example, the sequence is not an arithmetic progression, but is instead generated by starting with 17 and adding either 3 or 5, thus allowing multiple common differences to generate it.
A semilinear set generalizes this idea to multiple dimensions -- it is a set of vectors of integers, rather than a set of integers.
Finite generalized arithmetic progression
A finite generalized arithmetic progression, or sometimes just generalized arithmetic progression (GAP), of dimension d is defined to be a set of the form
where . The product is called the size of the generalized arithmetic progression; the cardinality of the set can differ from the size if some elements of the set have multiple representations. If the cardinality equals the size, the progression is called proper. Generalized arithmetic progressions can be thought of as a projection of a higher dimensional grid into . This projection is injective if and only if the generalized arithmetic progression is proper.
Semilinear sets
Formally, an arithmetic progression of is an infinite sequence of the form , where and are fixed vectors in , called the initial vector and common
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https://en.wikipedia.org/wiki/Mordechai%20Nessyahu
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Mordechai Nessyahu (September 25, 1929 – April 23, 1997) was an Israeli political theorist and philosopher of science, as well as the originator of a worldview he called cosmotheism.
Biography
While studying physics and philosophy at the Hebrew University, Nessyahu began to formulate the worldview he eventually called cosmotheism. He exchanged several letters on the subject with Albert Einstein. In 1953 he published a book in Hebrew entitled מדע הקוסמוס וחברת המדע (Cosmic Science and the Scientific Society) which became the foundation of his eventual cosmotheistic formulation. Moshe Sharett, soon to be Israel's second prime minister, was so impressed by the book that he shared it with Prime Minister David Ben-Gurion. As a result, Nessyahu was appointed Director of the Research Department of the Israeli Labor Party. Nessyahu remained in this position until his death.
In 1968 he met Tsvi Bisk, a new immigrant from the United States, who became his assistant at the Research Department. This meeting triggered a renewed interest in cosmotheism with Bisk as his collaborator and translator. Numerous English-language drafts of the idea were produced over the years and sent to hundreds of thinkers around the world to solicit their opinions. The year he died Nessyahu finally published his work in book form in Hebrew.
The cosmotheistic hypothesis
The cosmotheistic hypothesis stipulates that the Big Bang that created our cosmos was a local event in an infinite universe — a universe t
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https://en.wikipedia.org/wiki/Aris%20Poulianos
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Aris Poulianos (born 24 July 1924) is a Greek anthropologist and archaeologist.
Early life and career
Before becoming an anthropologist, Poulianos fought during World War II as a member of ELAS in 1942 and 1943. During the Greek Civil War, he fought on the side of the DSE in 1948 and 1949. After the war, Poulianos studied biology at Queens College, New York and then anthropology in Moscow.
He earned his Ph.D in Moscow under the supervision of anthropologist F. G. Debets in 1961 with a dissertation on The Origin of the Greeks, a work based on anthropometric studies of a sample of present-day Greek people. In 1965, he returned to Greece as a researcher. In 1971, Poulianos founded the Anthropological Association of Greece, which is now run by his son, Nikos. This organization has had a long-standing dispute with the Greek Ministry of Culture, after the latter's attempts to evict the association from the excavation site in the Petralona Cave, which was conceded to them after a 1981 contract. In 1976, Poulianos founded the Department of Paleoanthropology-Spelaeology, which functions within the Greek Ministry of Culture.
Petralona skull
Since the 1970s, Poulianos has investigated early hominid remains found in a cave near Petralona, Greece, and has become known for controversial claims over their age. According to Poulianos, the Petralona Cave was accidentally discovered in 1959 by local villagers searching for a spring in the mountainside. The Petralona skull, specifically, wa
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https://en.wikipedia.org/wiki/Second-generation%20wavelet%20transform
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In signal processing, the second-generation wavelet transform (SGWT) is a wavelet transform where the filters (or even the represented wavelets) are not designed explicitly, but the transform consists of the application of the Lifting scheme.
Actually, the sequence of lifting steps could be converted to a regular discrete wavelet transform, but this is unnecessary because both design and application is made via the lifting scheme.
This means that they are not designed in the frequency domain, as they are usually in the classical (so to speak first generation) transforms such as the DWT and CWT).
The idea of moving away from the Fourier domain was introduced independently by David Donoho and Harten in the early 1990s.
Calculating transform
The input signal is split into odd and even samples using shifting and downsampling. The detail coefficients are then interpolated using the values of and the prediction operator on the even values:
The next stage (known as the updating operator) alters the approximation coefficients using the detailed ones:
The functions prediction operator and updating operator
effectively define the wavelet used for decomposition.
For certain wavelets the lifting steps (interpolating and updating) are repeated several times before the result is produced.
The idea can be expanded (as used in the DWT) to create a filter bank with a number of levels.
The variable tree used in wavelet packet decomposition can also be used.
Advantages
The SGWT
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https://en.wikipedia.org/wiki/Bruce%20Forbes
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Bruce David Forbes (born March 30, 1948) is an ordained minister in the United Methodist Church. Born in Michigan, he grew up in Mitchell, South Dakota. His parents, Ernest Linwood Forbes and Marie Louise Forbes, met in Rochester. Ernie eventually became a hospital administrator at Methodist Hospital in Mitchell. Marie was a mathematics teacher as well as a librarian. Forbes resides in Sioux City, Iowa and has one son, Matthew Forbes.
Bruce Forbes holds a BA in religious studies from Morningside College, an MTh from Perkins School of Theology at Southern Methodist University, and a PhD from Princeton Theological Seminary. His formal academic training is in the history of Christianity, but he has also developed a special interest in the analysis of popular culture. Forbes is a former department chair and professor of religious studies at Morningside College in Sioux City, Iowa.
He is the co-editor of two books: Religion and Popular Culture in America (2000, second edition in 2005, third edition in 2017), co-edited with Jeffrey H. Mahan, and Rapture, Revelation and the End Times: An Exploration of the Left Behind Series (2004), co-edited with Djeanne Halgren Kilde. He is also the author of two non-fiction books: Christmas: A Candid History (2007) and America's Favorite Holidays: Candid Histories (2015).
References
1948 births
Living people
Morningside University alumni
Southern Methodist University alumni
Princeton Theological Seminary alumni
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https://en.wikipedia.org/wiki/Alexander%20Klibanov
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Alexander Klibanov may refer to:
Alexander Klibanov (biologist), professor of biology at the University of Virginia
Alexander Klibanov (chemist), professor of chemistry and bioengineering at the Massachusetts Institute of Technology
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https://en.wikipedia.org/wiki/Bohumil%20Sekla
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Bohumil Sekla (16 May 1901 in Bohuslavice – 7 August 1987 in Prague) was a Czechoslovak biologist. He specialised in genetics and was known as an expert in determining parenthood by the biological-hereditary method.
Sekla studied at Charles University in Prague, first history, then psychology and finally biology. After his studies he worked at the university and became one of the founders of modern genetics in Czechoslovakia. During 1933-45 Sekla was the leader of Czechoslovakian eugenic society (Československá eugenická společnost). During the 1950s he needed to defend genetics against Lysenkoism. When this theory got discredited he got the chance to establish and lead modern research institutes (Department of Human and Medical Genetics of the Biological Institute in 1969 and Department of Medical Genetics of the Teaching Hospital in 1970). Due to political activity during Prague Spring Sekla was forced into retirement but he continued to work as physician-specialist until 1985.
External links
Detailed biography (in Czech)
Short biography (in Czech)
1901 births
1987 deaths
Czechoslovak biologists
Charles University alumni
Recipients of the Order of Tomáš Garrigue Masaryk
People from Kyjov
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https://en.wikipedia.org/wiki/Ivan%20Honl
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Ivan Honl (23 April 1866 in Zbýšov, Moravia – 7 June 1936 in , Náchod, Czechoslovakia) was a Czech bacteriologist, serologist and activist in the struggle against tuberculosis. Honl became one of founders of Czech microbiology.
Under the guidance of Jaroslav Hlava Honl gained his habilitation in bacteriology at Charles University in Prague in 1898. In 1919 he was named head to the new Czech Bacteriological Institute (Ústav pro bakteriologii a sérologii Lékařské fakulty Univerzity Karlovy). .
Honl was one of the early researchers of antibiotics. At the end of the 1890s he isolated a product of Bacterium pyocyaneum (today called Pseudomonas aeruginosa), which was used as medicine (Anginol) from the start of WWI until it was replaced by penicillin after WWII.
In 1899 he co-founded an institute to treat tuberculosis in Czechoslovakia and was active in this struggle for decades.
External links
Short biography (in Czech)
1866 births
1936 deaths
People from Zbýšov
Czech biologists
Czech microbiologists
Charles University alumni
Scientists from Austria-Hungary
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https://en.wikipedia.org/wiki/Single%20crystal
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In materials science, a single crystal (or single-crystal solid or monocrystalline solid) is a material in which the crystal lattice of the entire sample is continuous and unbroken to the edges of the sample, with no grain boundaries. The absence of the defects associated with grain boundaries can give monocrystals unique properties, particularly mechanical, optical and electrical, which can also be anisotropic, depending on the type of crystallographic structure. These properties, in addition to making some gems precious, are industrially used in technological applications, especially in optics and electronics.
Because entropic effects favor the presence of some imperfections in the microstructure of solids, such as impurities, inhomogeneous strain and crystallographic defects such as dislocations, perfect single crystals of meaningful size are exceedingly rare in nature. The necessary laboratory conditions often add to the cost of production. On the other hand, imperfect single crystals can reach enormous sizes in nature: several mineral species such as beryl, gypsum and feldspars are known to have produced crystals several meters across.
The opposite of a single crystal is an amorphous structure where the atomic position is limited to short-range order only. In between the two extremes exist polycrystalline, which is made up of a number of smaller crystals known as crystallites, and paracrystalline phases. Single crystals will usually have distinctive plane faces and som
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https://en.wikipedia.org/wiki/Thermal%20Hall%20effect
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In solid-state physics, the thermal Hall effect, also known as the Righi–Leduc effect, named after independent co-discoverers Augusto Righi and Sylvestre Anatole Leduc, is the thermal analog of the Hall effect. Given a thermal gradient across a solid, this effect describes the appearance of an orthogonal temperature gradient when a magnetic field is applied.
For conductors, a significant portion of the thermal current is carried by the electrons. In particular, the Righi–Leduc effect describes the heat flow resulting from a perpendicular temperature gradient and vice versa. The Maggi–Righi–Leduc effect describes changes in thermal conductivity when placing a conductor in a magnetic field.
A thermal Hall effect has also been measured in a paramagnetic insulators, called the "phonon Hall effect". In this case, there are no charged currents in the solid, so the magnetic field cannot exert a Lorentz force. An analogous thermal Hall effect for neutral particles exists in polyatomic gases, known as the Senftleben–Beenakker effect.
Measurements of the thermal Hall conductivity are used to distinguish between the electronic and lattice contributions to thermal conductivity. These measurements are especially useful when studying superconductors.
Description
Given a conductor or semiconductor with a temperature difference in the x-direction and a magnetic field B perpendicular to it in the z-direction, then a temperature difference can occur in the transverse y-direction,
The Righ
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https://en.wikipedia.org/wiki/Mathematics%20%28producer%29
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Ronald Maurice Bean, better known professionally as Mathematics (also known as Allah Mathematics) (born October 21, 1971), is a hip hop producer and DJ for the Wu-Tang Clan and its solo and affiliate projects. He designed the Wu-Tang Clan logo.
Biography
Born and raised in Jamaica, Queens, New York, Mathematics was introduced to hip hop by his brother who used to bring home recordings of the genre's pioneers like Grandmaster Flash & The Furious Five, Treacherous Three and Cold Crush Brothers. He began his career in 1987 DJing block parties and park jams in Baisley Projects, going by the name Supreme Cut Master. In 1988, he became the full-time DJ for experienced rapper Victor C, doing countless shows in clubs and colleges in New York City.
In 1990, Mathematics linked up with GZA/Genius, who would soon become one of the Wu-Tang Clan's founding members, but at the time was struggling to build a career on the Cold Chillin' label. This partnership earned Mathematics a spot on his first official tour, The Cold Chillin Blizzard Tour (with popular acts such as Biz Markie, Big Daddy Kane, Kool G. Rap & DJ Polo and Marley Marl).
GZA left Cold Chillin after his first album, Words from the Genius, did not achieve the sales target that was anticipated. He and Mathematics took to the road again, but this time with the help of GZA's cousins, RZA and Ol' Dirty Bastard. These three soon became the founding members of Wu-Tang Clan, then known as All In Together Now. The group soon dissolve
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https://en.wikipedia.org/wiki/Continuity
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Continuity or continuous may refer to:
Mathematics
Continuity (mathematics), the opposing concept to discreteness; common examples include
Continuous probability distribution or random variable in probability and statistics
Continuous game, a generalization of games used in game theory
Law of continuity, a heuristic principle of Gottfried Leibniz
Continuous function, in particular:
Continuity (topology), a generalization to functions between topological spaces
Scott continuity, for functions between posets
Continuity (set theory), for functions between ordinals
Continuity (category theory), for functors
Graph continuity, for payoff functions in game theory
Continuity theorem may refer to one of two results:
Lévy's continuity theorem, on random variables
Kolmogorov continuity theorem, on stochastic processes
In geometry:
Parametric continuity, for parametrised curves
Geometric continuity, a concept primarily applied to the conic sections and related shapes
In probability theory
Continuous stochastic process
Science
Continuity equations applicable to conservation of mass, energy, momentum, electric charge and other conserved quantities
Continuity test for an unbroken electrical path in an electronic circuit or connector
In materials science:
a colloidal system, consists of a dispersed phase evenly intermixed with a continuous phase
a continuous wave, an electromagnetic wave of constant amplitude and frequency
Entertainment
Continuity (broadcasting),
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https://en.wikipedia.org/wiki/William%20F.%20Harrah
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William Fisk Harrah (September 2, 1911 – June 30, 1978) was an American businessman and the founder of Harrah's Hotel and Casinos, now part of Caesars Entertainment.
Early years and education
Harrah was born in South Pasadena, California, the son of attorney and politician John Harrah.
Harrah studied mechanical engineering at UCLA where he was a member of the Phi Delta Theta fraternity. Harrah was forced to drop out because of the Great Depression. He worked at various family businesses including a pool hall, a hot dog stand, a shooting gallery, and a bingo-style operation called the "Circle" or "Reno Game."
Gaming beginnings
Bingo was illegal in California, but games of skill based on bingo were legal. The Reno Game (later called the Circle Game) involved rolling a ball down a board where it would register a card suit and number. If one of the 33 players seated in a circle around the board matched a four-card sequence, he or she won, unless they were a shill and, working for the house. (The use of shills to fill the games upset players, but John Harrah felt they were necessary.)
The Reno Game was shut down several times by local authorities, but each time, lawyer John Harrah would get his permit reinstated. Still, the cost of doing business was high. When twenty-year-old Bill told his father he should get rid of the shills and put more money into the business, John challenged him to run the operation by himself. Bill said, "Dad, that would suit me just fine," and paid
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https://en.wikipedia.org/wiki/Robert%20Wilson%20%28astronomer%29
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Sir Robert Wilson (16 April 1927 – 2 September 2002) was a British astronomer and physicist. He studied physics at King's College, Durham and obtained his PhD at the University of Edinburgh, where he worked at the Royal Observatory on stellar spectra. His works laid the groundwork for the development of the Great Space Observatories, such as the Hubble Space Telescope.
In 1959 Wilson joined the Plasma Spectroscopy Group at Harwell Laboratory where he was responsible for measuring the temperature in the Zeta experiment, confirming that it had not been hot enough to have produced thermonuclear fusion. As head of the Plasma Spectroscopy Group at Culham, he led a programme of rocket observations of ultraviolet spectra of the Sun and stars. By placing telescopes on rockets and satellites it was possible to avoid the absorption of the ultraviolet light by the Earth's atmosphere and gain a great deal of information about the hot plasmas especially in the Sun's chromosphere and corona.
Wilson then became involved in the European Space Research Organization's first astronomy satellite, the TD-1A mission, and led the British collaboration with Belgium in the S2/68 experiment which in 1972 conducted the first all sky survey in the ultraviolet.
Wilson was best known for his role as "father" of the International Ultraviolet Explorer (IUE) satellite. This had started life in 1964 as a proposal to ESRO for a Large Astronomical Satellite, which proved too expensive and studies were aband
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https://en.wikipedia.org/wiki/James%20Napier%20%28chemist%29
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James Napier (1810 – 1 December 1884) was a Scottish industrial chemist and antiquarian. He was a Fellow of the Royal Society of Edinburgh.
Life
James was born in June 1810 in Partick, Glasgow the son of James Napier, a gardener, and Margaret Buchanan, a seamstress. He was apprenticed as a dyer and attended extramural classes in chemistry at Glasgow University under Prof Thomas Graham.
Napier made several important advances within industrial chemistry and lodged several patents.
He joined the Philosophical Society of Glasgow in 1849, and many of his 32 known scientific papers were presented to the Society. He was elected a Fellow of the Royal Society of Edinburgh in 1876. His proposers were James Young, George Forbes, Lord Kelvin, and John Hutton Balfour.
After his wife died in March 1881, he never fully recovered from the event, and he died at his home, Maryfield, Bothwell, Lanarkshire on 1 December 1884.
Family
In October 1831 he married Christina McIndoe. They had eight children.
Publications
Amongst his publications are:
Manufacturing Art in Ancient Times
Notes and Reminiscences of Partick
Folk Lore or Superstitious Beliefs in the West of Scotland within This Century (1879)
References
External links
1810 births
1884 deaths
19th-century Scottish scientists
Scientists from Glasgow
Fellows of the Royal Society of Edinburgh
James
Scottish chemists
Scottish antiquarians
Scottish folklorists
19th-century Scottish historians
Victorian writers
19th-century an
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https://en.wikipedia.org/wiki/Sulfone
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In organic chemistry, a sulfone is a organosulfur compound containing a sulfonyl () functional group attached to two carbon atoms. The central hexavalent sulfur atom is double-bonded to each of two oxygen atoms and has a single bond to each of two carbon atoms, usually in two separate hydrocarbon substituents.
Synthesis and reactions
By oxidation of thioethers and sulfoxides
Sulfones are typically prepared by organic oxidation of thioethers, often referred to as sulfides. Sulfoxides are intermediates in this route. For example, dimethyl sulfide oxidizes to dimethyl sulfoxide and then to dimethyl sulfone.
From SO2
Sulfur dioxide is a convenient and widely used source of the sulfonyl functional group. Specifically, Sulfur dioxide participates in cycloaddition reactions with dienes.
The industrially useful solvent sulfolane is prepared by addition of sulfur dioxide to buta-1,3-diene followed by hydrogenation of the resulting sulfolene.
From sulfonyl and sulfuryl halides
Sulfones are prepared under conditions used for Friedel–Crafts reactions using sources of derived from sulfonyl halides and sulfonic acid anhydrides. Lewis acid catalysts such as and are required.
Sulfones have been prepared by nucleophilic displacement of halides by sulfinates:
ArSO2Na + Ar'Cl -> Ar(Ar')SO2 + NaCl
Reactions
Sulfone is a relatively inert functional group, being weakly basic (compared to sulfoxides). They are non-oxidizing. In the Ramberg–Bäcklund reaction and the Julia olefinat
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https://en.wikipedia.org/wiki/Range%20state
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Range state is a term generally used in zoogeography and conservation biology to refer to any nation that exercises jurisdiction over any part of a range which a particular species, taxon or biotope inhabits, or crosses or overflies at any time on its normal migration route. The term is often expanded to also include, particularly in international waters, any nation with vessels flying their flag that engage in exploitation (e.g. hunting, fishing, capturing) of that species. Countries in which a species occurs only as a vagrant or ‘accidental’ visitor outside of its normal range or migration route are not usually considered range states.
Because governmental conservation policy is often formulated on a national scale, and because in most countries, both governmental and private conservation organisations are also organised at the national level, the range state concept is often used by international conservation organizations in formulating their conservation and campaigning policy.
An example of one such organization is the Convention on the Conservation of Migratory Species of Wild Animals (CMS, or the “Bonn Convention”). It is a multilateral treaty focusing on the conservation of critically endangered and threatened migratory species, their habitats and their migration routes. Because such habitats and/or migration routes may span national boundaries, conservation efforts are less likely to succeed without the cooperation, participation, and coordination of each of
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https://en.wikipedia.org/wiki/Sulfoxide
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In organic chemistry, a sulfoxide, also called a sulfoxide, is an organosulfur compound containing a sulfinyl () functional group attached to two carbon atoms. It is a polar functional group. Sulfoxides are oxidized derivatives of sulfides. Examples of important sulfoxides are alliin, a precursor to the compound that gives freshly crushed garlic its aroma, and dimethyl sulfoxide (DMSO), a common solvent.
Structure and bonding
Sulfoxides feature relatively short S–O distances. In DMSO, the S–O distance is 1.531 Å. The sulfur center is pyramidal; the sum of the angles at sulfur is about 306°.
Sulfoxides are generally represented with the structural formula R−S(=O)−R', where R and R' are organic groups. The bond between the sulfur and oxygen atoms is intermediate of a dative bond and a polarized double bond. The double-bond resonance form implies 10 electrons around sulfur (10-S-3 in N-X-L notation). The double-bond character of the S−O bond may be accounted for by donation of electron density into C−S antibonding orbitals ("no-bond" resonance forms in valence-bond language). Nevertheless, due to its simplicity and lack of ambiguity, the IUPAC recommends use of the expanded octet double-bond structure to depict sulfoxides, rather than the dipolar structure or structures that invoke "no-bond" resonance contributors. The S–O interaction has an electrostatic aspect, resulting in significant dipolar character, with negative charge centered on oxygen.
Chirality
A lone pair
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https://en.wikipedia.org/wiki/FSSP
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FSSP may refer to:
Families of structurally similar proteins, a protein structures database
Federal Bailiffs Service (Russia), abbreviated FSSP in Russian
Firing squad synchronization problem, a problem in computer science and cellular automata
Frances Slocum State Park, a state park in Luzerne County, Pennsylvania
Priestly Fraternity of Saint Peter, a society of traditionalist Catholic priests and seminarians
Fresh Start Schools Programme, a programme for schools in South Africa
Forward Scattering Spectrometer Probe, a class of optical instruments designed to measure size and concentration of particles suspended in the air (such as cloud droplets)
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https://en.wikipedia.org/wiki/Aether%20theories
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In physics, aether theories (also known as ether theories) propose the existence of a medium, a space-filling substance or field as a transmission medium for the propagation of electromagnetic or gravitational forces. "Since the development of special relativity, theories using a substantial aether fell out of use in modern physics, and are now replaced by more abstract models."
This early modern aether has little in common with the aether of classical elements from which the name was borrowed. The assorted theories embody the various conceptions of this medium and substance.
Historical models
Luminiferous aether
Isaac Newton suggests the existence of an aether in the Third Book of Opticks (1st ed. 1704; 2nd ed. 1718): "Doth not this aethereal medium in passing out of water, glass, crystal, and other compact and dense bodies in empty spaces, grow denser and denser by degrees, and by that means refract the rays of light not in a point, but by bending them gradually in curve lines? ...Is not this medium much rarer within the dense bodies of the Sun, stars, planets and comets, than in the empty celestial space between them? And in passing from them to great distances, doth it not grow denser and denser perpetually, and thereby cause the gravity of those great bodies towards one another, and of their parts towards the bodies; every body endeavouring to go from the denser parts of the medium towards the rarer?"
In the 19th century, luminiferous aether (or ether), meaning ligh
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https://en.wikipedia.org/wiki/SNS
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SNS may refer to:
Science and technology
Biology and medicine
Somatic nervous system or voluntary nervous system
Supplemental nursing system, to provide additional milk to a nursing infant
Sympathetic nervous system, part of the autonomic nervous system
Computing
Social networking service, social website
Amazon Simple Notification Service, for mobile devices
Other uses in science and technology
Spallation Neutron Source, Oak Ridge, Tennessee, US
US Strategic National Stockpile of medical supplies
Tin(II) sulfide, SnS
Organizations
Businesses
SNS Bank, Netherlands
Street News Service, for street newspapers
Political parties
Serbian Progressive Party (Srpska napredna stranka)
Serb People's Party (Srpska narodna stranka)
Slovak National Party (Slovenská národná strana) (1990–present)
Slovak National Party (historical) (1871–1938)
Slovenian National Party (Slovenska nacionalna stranka)
Other organizations
Scuola Normale Superiore, an Italian higher education institution
Serviço Nacional de Saúde, the Portuguese national health service
Sistema Nacional de Salud, the national health system of Spain
Société de natation de Strasbourg, French water polo team
Special Night Squads, a former Jewish-British military unit
Stoke Newington School, London, UK
Other uses
Salinas Municipal Airport, Monterey County, California, US, IATA code
SNS, the product code used by Nintendo for Super NES hardware (e.g. SNS-001)
SNS, abbreviation for "Salomon Nordic System",
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