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https://en.wikipedia.org/wiki/Megakaryoblast
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A megakaryoblast is a precursor cell to a promegakaryocyte, which in turn becomes a megakaryocyte during haematopoiesis. It is the beginning of the thrombocytic series.
Development
The megakaryoblast derives from a CFU-Meg colony unit of pluripotential hemopoietic stem cells. (Some sources use the term "CFU-Meg" to identify the CFU.) The CFU-Meg derives from the CFU-GEMM (common myeloid progenitor).
Structure
These cells tend to range from 8μm to 30μm, owing to the variation in size between different megakaryoblasts. The nucleus is three to five times the size of the cytoplasm, and is generally round or oval in shape. Several nucleoli are visible, while the chromatin varies from cell to cell, ranging from fine to heavy and dense. The cytoplasm is generally basophilic and stains blue. In smaller cells, it contains no granules, but larger megakaryoblasts may contain fine granules.
References
External links
Photo
Photo
Photo
Life cycle
Leukocytes
de:Thrombopoese#Megakaryoblast
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https://en.wikipedia.org/wiki/Myeloid%20tissue
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Myeloid tissue, in the bone marrow sense of the word myeloid (myelo- + -oid), is tissue of bone marrow, of bone marrow cell lineage, or resembling bone marrow, and myelogenous tissue (myelo- + -genous) is any tissue of, or arising from, bone marrow; in these senses the terms are usually used synonymously, as for example with chronic myeloid/myelogenous leukemia.
In hematopoiesis, myeloid cells, or myelogenous cells are blood cells that arise from a progenitor cell for granulocytes, monocytes, erythrocytes, or platelets (the common myeloid progenitor, that is, CMP or CFU-GEMM), or in a narrower sense also often used, specifically from the lineage of the myeloblast (the myelocytes, monocytes, and their daughter types). Thus, although all blood cells, even lymphocytes, are normally born in the bone marrow in adults, myeloid cells in the narrowest sense of the term can be distinguished from lymphoid cells, that is, lymphocytes, which come from common lymphoid progenitor cells that give rise to B cells and T cells. Those cells' differentiation (that is, lymphopoiesis) is not complete until they migrate to lymphatic organs such as the spleen and thymus for programming by antigen challenge. Thus, among leukocytes, the term myeloid is associated with the innate immune system, in contrast to lymphoid, which is associated with the adaptive immune system. Similarly, myelogenous usually refers to nonlymphocytic white blood cells, and erythroid can often be used to distinguish "erythroc
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https://en.wikipedia.org/wiki/Co-Co%20locomotive
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Co-Co is the wheel arrangement for diesel and electric locomotives with two six-wheeled bogies with all axles powered, with a separate traction motor per axle. The equivalent UIC classification (Europe) for this arrangement is Co′Co′, or C-C for AAR (North America).
Use
Co-Cos are most suited to freight work as the extra wheels give them good traction. They are also popular because the greater number of axles results in a lower axle load to the track.
History
The first mainline diesel-electric locomotives were of Bo-Bo arrangement. As they grew in power and weight, from 1937 the EMD E-units used an A1A-A1A layout with six axles to reduce axle load, but only four of them were powered. After WWII, the British LMS ordered two prototype locomotives with some of the first Co-Co arrangements.
The first C-C design recorded was a narrow-gauge Hornsby opposed-piston Hornsby-Akroyd-engined locomotive of 1903 for the Chattenden and Upnor Railway. There was a two-speed mechanical transmission with drive shafts to the bogies and the axles on each bogie were linked by coupling rods.
Variants
Electric locomotives
There were initially few electric locomotives with this wheel arrangement, as they are usually lighter than diesel-electrics of similar power and so could manage a similar axle loading with a simpler Bo-Bo arrangement. Some of the few early examples were the French CC 7100 of 1949 and the British Railways EM2 of 1953.
As high-speed electric locomotives in the 1980s began
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https://en.wikipedia.org/wiki/Silencer%20%28genetics%29
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In genetics, a silencer is a DNA sequence capable of binding transcription regulation factors, called repressors. DNA contains genes and provides the template to produce messenger RNA (mRNA). That mRNA is then translated into proteins. When a repressor protein binds to the silencer region of DNA, RNA polymerase is prevented from transcribing the DNA sequence into RNA. With transcription blocked, the translation of RNA into proteins is impossible. Thus, silencers prevent genes from being expressed as proteins.
RNA polymerase, a DNA-dependent enzyme, transcribes the DNA sequences, called nucleotides, in the 3' to 5' direction while the complementary RNA is synthesized in the 5' to 3' direction. RNA is similar to DNA, except that RNA contains uracil, instead of thymine, which forms a base pair with adenine. An important region for the activity of gene repression and expression found in RNA is the 3' untranslated region. This is a region on the 3' terminus of RNA that will not be translated to protein but includes many regulatory regions.
Not much is yet known about silencers but scientists continue to study in hopes to classify more types, locations in the genome, and diseases associated with silencers.
Functionality
Locations within the genome
A silencer is a sequence-specific element that induces a negative effect on the transcription of its particular gene. There are many positions in which a silencer element can be located in DNA. The most common position is found ups
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https://en.wikipedia.org/wiki/Bo-Bo
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B-B and Bo-Bo are the Association of American Railroads (AAR) and British classifications of wheel arrangement for railway locomotives with four axles in two individual bogies. They are equivalent to the B′B′ and Bo′Bo′ classifications in the UIC system. The arrangement of two, two-axled, bogies is a common wheel arrangement for modern electric and diesel locomotives.
Bo-Bo
Bo-Bo is the UIC indication of a wheel arrangement for railway vehicles with four axles in two individual bogies, all driven by their own traction motors. It is a common wheel arrangement for modern electric and diesel-electric locomotives, as well as power cars in electric multiple units.
Most early electric locomotives shared commonalities with the steam engines of their time. These features included side rods and frame mounted driving axles with leading and trailing axles. The long rigid wheelbase and the leading and trailing axles reduced cornering stability and increased weight.
The Bo-Bo configuration allowed for higher cornering speeds due to the smaller rigid wheelbase. Furthermore, it allowed better adhesion because all the wheels were now powered. Due to the absence of frame mounted wheels no leading or trailing axles were necessary to aid cornering, reducing weight and maintenance requirements.
Due to the advent of modern motors and electronics more power can be brought to the rail with only a few axles. Modern electric locomotives can deliver up to 6400 kW on only four axles. For very heav
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https://en.wikipedia.org/wiki/Tip%20growth
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Tip growth is an extreme form of polarised growth of living cells that results in an elongated cylindrical cell morphology with a rounded tip at which the growth activity takes place. Tip growth occurs in algae (e.g., Acetabularia acetabulum), fungi (hyphae) and plants (e.g. root hairs and pollen tubes).
Tip growth is a process that has many similarities in diverse walled cells such as pollen tubes, root hairs, and hyphae.
Fungal tip growth and hyphal tropisms
Fungal hyphae extend continuously at their extreme tips, where enzymes are released into the environment and where new wall materials are synthesised. The rate of tip extension can be extremely rapid - up to 40 micrometres per minute. It is supported by the continuous movement of materials into the tip from older regions of the hyphae. So, in effect, a fungal hypha is a continuously moving mass of protoplasm in a continuously extending tube. This unique mode of growth - apical growth - is the hallmark of fungi, and it accounts for much of their environmental and economic significance.
References
Developmental biology
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https://en.wikipedia.org/wiki/Production%20fluid
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Production fluid is the fluid mixture of oil, gas and water in formation fluid that flows to the surface of an oil well from a reservoir. Its consistency and composition varies.
Fluids may be described by a multitude of characteristics including:
Water cut - the proportion of the fluid, which is water rather than hydrocarbons.
API gravity - the oilfield measurement of the weight of the hydrocarbons.
GOR - Gas to oil ratio describing how many standard cubic feet of gas can be obtained for every stock tank barrel of oil.
H2S - the concentration of this gas. Fluids with a high concentration of H2S are described as "sour".
External links
Schlumberger Oilfield Glossary: produced fluid
Petroleum production
Natural gas
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https://en.wikipedia.org/wiki/Production%20string
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The production string is a part of an oil well that is composed of the production tubing and other completion components and serves as the conduit through which the production fluid flows from the oil reservoir to the surface through the wellhead. Its purpose is to both contain the fluids from contaminating the environment or eroding the other well structures, such as the casing.
External links
Schlumberger Oilfield Glossary: production string
Petroleum production
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https://en.wikipedia.org/wiki/Sudan%20II
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Sudan II (Solvent Orange 7, C.I. 12140, C18H16N2O) is a lysochrome (fat-soluble dye) azo dye used for staining of triglycerides in frozen sections, and some protein bound lipids and lipoproteins on paraffin sections. It has the appearance of red powder with melting point 156–158 °C and maximum absorption at 493(420) nm.
Uses
In industry, it is used to color nonpolar substances like oils, fats, waxes, greases, various hydrocarbon products, and acrylic emulsions.
It was used as food dye under the designation FD&C Red 32 in the US until the FDA banned its use in food in 1956 due to toxicity.
References
Azo dyes
Sudan dyes
2-Naphthols
Alkyl-substituted benzenes
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https://en.wikipedia.org/wiki/ACM%20Computing%20Classification%20System
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The ACM Computing Classification System (CCS) is a subject classification system for computing devised by the Association for Computing Machinery (ACM). The system is comparable to the Mathematics Subject Classification (MSC) in scope, aims, and structure, being used by the various ACM journals to organize subjects by area.
History
The system has gone through seven revisions, the first version being published in 1964, and revised versions appearing in 1982, 1983, 1987, 1991, 1998, and the now current version in 2012.
Structure
It is hierarchically structured in four levels. For example, one branch of the hierarchy contains:
Computing methodologies
Artificial intelligence
Knowledge representation and reasoning
Ontology engineering
See also
Computer Science Ontology
Physics and Astronomy Classification Scheme
arXiv, a preprint server allowing submitted papers to be classified using the ACM CCS
Physics Subject Headings
References
.
.
.
External links
dl.acm.org/ccs is the homepage of the system, including links to four complete versions of the system:
the 1964 version
the 1991 version
the 1998 version
the current 2012 version.
The ACM Computing Research Repository uses a classification scheme that is much coarser than the ACM subject classification, and does not cover all areas of CS, but is intended to better cover active areas of research. In addition, papers in this repository are classified according to the ACM subject classification.
Computing Classific
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https://en.wikipedia.org/wiki/Dennis%20Hof%27s%20Love%20Ranch
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Dennis Hof's Love Ranch, known as the Cherry Patch Ranch prior to 2010, is one of two brothels in Crystal, Nevada. It is also referred to as the Love Ranch South or Love Ranch Las Vegas due to its proximity to Las Vegas.
Both brothels in Crystal were owned by Maynard "Joe" Richards. In 2010, Richards sold both to Dennis Hof, who said Heidi Fleiss would be a consultant.
The license for the brothel was suspended in February 2018 for alleged unauthorized structural changes and fire and safety violations and then closed down by the county again on August 8, 2018, for late payment of fees.
On August 27, 2018, Judge Richard Boulware ruled that Dennis Hof may re-open Love Ranch Vegas as of August 28, 2018, stating that other brothels did not have their licenses revoked when they were late renewing.
Death of owner
On October 16, 2018, Dennis Hof, the owner of the Love Ranch property was found dead in his bedroom at the Love Ranch. He is believed to have died in his sleep due to natural causes. Hof died at his Love Ranch in Pahrump, Nevada, following a party for his 72nd birthday that had been attended by Flavor Flav, Joe Arpaio, Grover Norquist and Ron Jeremy, the last of whom found Hof unresponsive. Police did not suspect foul play at the time of his death.
Other incidents
On October 13, 2015, professional basketball player Lamar Odom was hospitalized after being discovered unconscious at the Love Ranch. Odom visited the ranch seeking the company of Cherry Ryder and Madison
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https://en.wikipedia.org/wiki/Multiple%20line%20segment%20intersection
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In computational geometry, the multiple line segment intersection problem supplies a list of line segments in the Euclidean plane and asks whether any two of them intersect (cross).
Simple algorithms examine each pair of segments. However, if a large number of possibly intersecting segments are to be checked, this becomes increasingly inefficient since most pairs of segments are not close to one another in a typical input sequence. The most common, and more efficient, way to solve this problem for a high number of segments is to use a sweep line algorithm, where we imagine a line sliding across the line segments and we track which line segments it intersects at each point in time using a dynamic data structure based on binary search trees. The Shamos–Hoey algorithm applies this principle to solve the line segment intersection detection problem, as stated above, of determining whether or not a set of line segments has an intersection; the Bentley–Ottmann algorithm works by the same principle to list all intersections in logarithmic time per intersection.
See also
Bentley–Ottmann algorithm
References
Further reading
Chapter 2: Line Segment Intersection, pp. 19–44.
Thomas H. Cormen, Charles E. Leiserson, Ronald L. Rivest, and Clifford Stein. Introduction to Algorithms, Second Edition. MIT Press and McGraw-Hill, 1990. . Section 33.2: Determining whether any pair of segments intersects, pp. 934–947.
J. L. Bentley and T. Ottmann., Algorithms for reporting and counting g
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https://en.wikipedia.org/wiki/Charcot%E2%80%93Leyden%20crystals
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Charcot–Leyden crystals are microscopic crystals composed of eosinophil protein galectin-10 found in people who have allergic diseases such as asthma or parasitic infections such as parasitic pneumonia or ascariasis.
Appearance
Charcot–Leyden crystals are composed of an eosinophilic lysophospholipase binding protein called Galectin -10. They vary in size and may be as large as 50 µm in length. Charcot–Leyden crystals are slender and pointed at both ends, consisting of a pair of hexagonal pyramids joined at their bases. Normally colorless, they are stained purplish-red by trichrome.
Clinical significance
They are indicative of a disease involving eosinophilic inflammation or proliferation, such as is found in allergic reactions (asthma, bronchitis, allergic rhinitis and rhinosinusitis) and parasitic infections such as Entamoeba histolytica, Necator americanus, and Ancylostoma duodenale.
Charcot–Leyden crystals are often seen pathologically in patients with bronchial asthma.
History
Friedrich Albert von Zenker was the first to notice these crystals, doing so in 1851, after which they were described jointly by Jean-Martin Charcot and Charles-Philippe Robin in 1853, then in 1872 by Ernst Viktor von Leyden.
See also
Curschmann's Spirals
References
External links
Tulane Lung pathology
Charcot Leyden crystals at UDEL
Scientists solve a century-old mystery to treat asthma and airway inflammation
Pathology
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https://en.wikipedia.org/wiki/Colan
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Colan may refer to:
Places
Colan, Cornwall, a village and civil parish in Cornwall, United Kingdom
A beach in the Piura Region of Peru
People
Gene Colan
Joanne Colan
Ioana Petcu-Colan
Nicolae Colan
Colan, a character in G.K. Chesterton's poem The Ballad of the White Horse
See also
Collan
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https://en.wikipedia.org/wiki/Callendar%E2%80%93Van%20Dusen%20equation
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The Callendar–Van Dusen equation is an equation that describes the relationship between resistance (R) and temperature (T) of platinum resistance thermometers (RTD).
As commonly used for commercial applications of RTD thermometers, the relationship between resistance and temperature is given by the following equations. The relationship above 0 °C (up to the melting point of aluminum ~ 660 °C) is a simplification of the equation that holds over a broader range down to -200 °C. The longer form was published in 1925 (see below) by M.S. Van Dusen and is given as:
While the simpler form was published earlier by Callendar, it is generally valid only over the range between 0 °C to 661 °C and is given as:
Where constants A, B, and C are derived from experimentally determined parameters α, β, and δ using resistance measurements made at 0 °C, 100 °C and 260 °C.
Together,
It is important to note that these equations are listed as the basis for the temperature/resistance tables for idealized platinum resistance thermometers and are not intended to be used for the calibration of an individual thermometer, which would require the experimentally determined parameters to be found.
These equations are cited in International Standards for platinum RTD's resistance versus temperature functions DIN/IEC 60751 (also called IEC 751), also adopted as BS-1904, and with some modification, JIS C1604.
The equation was found by British physicist Hugh Longbourne Callendar, and refined for measure
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https://en.wikipedia.org/wiki/Fatou%E2%80%93Lebesgue%20theorem
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In mathematics, the Fatou–Lebesgue theorem establishes a chain of inequalities relating the integrals (in the sense of Lebesgue) of the limit inferior and the limit superior of a sequence of functions to the limit inferior and the limit superior of integrals of these functions. The theorem is named after Pierre Fatou and Henri Léon Lebesgue.
If the sequence of functions converges pointwise, the inequalities turn into equalities and the theorem reduces to Lebesgue's dominated convergence theorem.
Statement of the theorem
Let f1, f2, ... denote a sequence of real-valued measurable functions defined on a measure space (S,Σ,μ). If there exists a Lebesgue-integrable function g on S which dominates the sequence in absolute value, meaning that |fn| ≤ g for all natural numbers n, then all fn as well as the limit inferior and the limit superior of the fn are integrable and
Here the limit inferior and the limit superior of the fn are taken pointwise. The integral of the absolute value of these limiting functions is bounded above by the integral of g.
Since the middle inequality (for sequences of real numbers) is always true, the directions of the other inequalities are easy to remember.
Proof
All fn as well as the limit inferior and the limit superior of the fn are measurable and dominated in absolute value by g, hence integrable.
The first inequality follows by applying Fatou's lemma to the non-negative functions fn + g and using the linearity of the Lebesgue integral. The last
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https://en.wikipedia.org/wiki/Fundamental%20constant
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In physics, the term fundamental constant may refer to:
Any physical constant which is part of an equation that expresses a fundamental physical law
One of the fundamental dimensionless physical constants
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https://en.wikipedia.org/wiki/Start%20codon
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The start codon is the first codon of a messenger RNA (mRNA) transcript translated by a ribosome. The start codon always codes for methionine in eukaryotes and archaea and a N-formylmethionine (fMet) in bacteria, mitochondria and plastids.
The start codon is often preceded by a 5' untranslated region (5' UTR). In prokaryotes this includes the ribosome binding site.
Alternative start codons
Alternative start codons are different from the standard AUG codon and are found in both prokaryotes (bacteria and archaea) and eukaryotes. Alternate start codons are still translated as Met when they are at the start of a protein (even if the codon encodes a different amino acid otherwise). This is because a separate transfer RNA (tRNA) is used for initiation.
Eukaryotes
Alternate start codons (non-AUG) are very rare in eukaryotic genomes. However, naturally occurring non-AUG start codons have been reported for some cellular mRNAs. Seven out of the nine possible single-nucleotide substitutions at the AUG start codon of dihydrofolate reductase are functional as translation start sites in mammalian cells. In addition to the canonical Met-tRNA Met and AUG codon pathway, mammalian cells can initiate translation with leucine using a specific leucyl-tRNA that decodes the codon CUG.
Candida albicans uses a CAG start codon.
Prokaryotes
Prokaryotes use alternate start codons significantly, mainly GUG and UUG.
E. coli uses 83% AUG (3542/4284), 14% (612) GUG, 3% (103) UUG and one or two oth
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https://en.wikipedia.org/wiki/Hydrophilicity%20plot
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A hydrophilicity plot is a quantitative analysis of the degree of hydrophobicity or hydrophilicity of amino acids of a protein. It is used to characterize or identify possible structure or domains of a protein.
The plot has amino acid sequence of a protein on its x-axis, and degree of hydrophobicity and hydrophilicity on its y-axis. There are a number of methods to measure the degree of interaction of polar solvents such as water with specific amino acids. For instance, the Kyte-Doolittle scale indicates hydrophobic amino acids, whereas the Hopp-Woods scale measures hydrophilic residues.
Analyzing the shape of the plot gives information about partial structure of the protein. For instance, if a stretch of about 20 amino acids shows positive for hydrophobicity, these amino acids may be part of alpha-helix spanning across a lipid bilayer, which is composed of hydrophobic fatty acids. On the converse, amino acids with high hydrophilicity indicate that these residues are in contact with solvent, or water, and that they are therefore likely to reside on the outer surface of the protein.
The data in the above table was generated using a computer program that evaluates the average hydrophobicity of segments within a protein and uses data collected from literature.
References
External links
ExPASy ProtScale
Protein Hydrophobicity Plots from Colorado State
Hydropathicity Plots from The World of Bioinformatics
Plots (graphics)
Protein structure
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https://en.wikipedia.org/wiki/Herman%20Branson
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Herman Russell Branson (August 14, 1914 – June 7, 1995) was an American physicist, chemist, best known for his research on the alpha helix protein structure, and was also the president of two colleges. He received a fellowship from the Rosenwald Foundation.
Early life
Branson received his B.S. from Virginia State College in 1936, and his Ph.D. in physics from the University of Cincinnati, under the direction of Boris Podolsky, in 1939. His thesis was in three parts, the first involved the interaction of x-rays with Tubifex tubifex (or sludge worm), the second involving the design and construction of an X-ray intensity measuring device, and the third section on the quantization of mass using the Dirac Equation. After a stint at Dillard University, he joined Howard University in 1941 as an assistant professor of physics and chemistry. As a scientist, Branson made significant contributions to how proteins work, and how they contribute to diseases such as sickle cell anemia. He remained at Howard for 27 years, achieving increasingly important positions, eventually becoming head of the physics department, director of a program in experimental science and mathematics, and working on the Office of Naval Research and Atomic Energy Commission Projects in Physics at Howard University. One of his students would include Marie Maynard Daly who was the first woman of color in the United States to earn her doctorate in chemistry.
Work on protein structure
In 1948, Branson took a le
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https://en.wikipedia.org/wiki/Neuron%20doctrine
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The neuron doctrine is the concept that the nervous system is made up of discrete individual cells, a discovery due to decisive neuro-anatomical work of Santiago Ramón y Cajal and later presented by, among others, H. Waldeyer-Hartz. The term neuron (spelled neurone in British English) was itself coined by Waldeyer as a way of identifying the cells in question. The neuron doctrine, as it became known, served to position neurons as special cases under the broader cell theory evolved some decades earlier. He appropriated the concept not from his own research but from the disparate observation of the histological work of Albert von Kölliker, Camillo Golgi, Franz Nissl, Santiago Ramón y Cajal, Auguste Forel and others.
Historical context
Theodor Schwann proposed in 1839 that the tissues of all organisms are composed of cells. Schwann was expanding on the proposal of his good friend Matthias Jakob Schleiden the previous year that all plant tissues were composed of cells. The nervous system stood as an exception. Although nerve cells had been described in tissue by numerous investigators including Jan Purkinje, Gabriel Valentin, and Robert Remak, the relationship between the nerve cells and other features such as dendrites and axons was not clear. The connections between the large cell bodies and smaller features could not be observed, and it was possible that neurofibrils would stand as an exception to cell theory as non-cellular components of living tissue. Technical limita
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https://en.wikipedia.org/wiki/Runge%27s%20theorem
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In complex analysis, Runge's theorem (also known as Runge's approximation theorem) is named after the German mathematician Carl Runge who first proved it in the year 1885. It states the following:
Denoting by C the set of complex numbers, let K be a compact subset of C and let f be a function which is holomorphic on an open set containing K. If A is a set containing at least one complex number from every bounded connected component of C\K then there exists a sequence of rational functions which converges uniformly to f on K and such that all the poles of the functions are in A.
Note that not every complex number in A needs to be a pole of every rational function of the sequence . We merely know that for all members of that do have poles, those poles lie in A.
One aspect that makes this theorem so powerful is that one can choose the set A arbitrarily. In other words, one can choose any complex numbers from the bounded connected components of C\K and the theorem guarantees the existence of a sequence of rational functions with poles only amongst those chosen numbers.
For the special case in which C\K is a connected set (in particular when K is simply-connected), the set A in the theorem will clearly be empty. Since rational functions with no poles are simply polynomials, we get the following corollary: If K is a compact subset of C such that C\K is a connected set, and f is a holomorphic function on an open set containing K, then there exists a sequence of polynomials
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https://en.wikipedia.org/wiki/Aurelio%20Gonz%C3%A1lez%20Puente
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Aurelio González Puente (born 26 July 1940) is a Spanish former road bicycle racer who won the Mountains classification in the 1968 Tour de France and the Mountains classification in the 1967 Giro d'Italia. He also won stages in the Tour de France, Giro d'Italia, Tour de Suisse and Dauphiné Libéré.
Major results
1967
Giro d'Italia
1st Mountains classification
1st Stage 22a
3rd Overall Vuelta a España
1968
Tour de France
1st Mountains classification
1st Stage 6
External links
1940 births
Living people
Spanish male cyclists
Spanish Tour de France stage winners
Spanish Giro d'Italia stage winners
People from Asón-Agüera
Tour de Suisse stage winners
Cyclists from Cantabria
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https://en.wikipedia.org/wiki/Co-receptor
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A co-receptor is a cell surface receptor that binds a signalling molecule in addition to a primary receptor in order to facilitate ligand recognition and initiate biological processes, such as entry of a pathogen into a host cell.
Properties
The term co-receptor is prominent in literature regarding signal transduction, the process by which external stimuli regulate internal cellular functioning. The key to optimal cellular functioning is maintained by possessing specific machinery that can carry out tasks efficiently and effectively. Specifically, the process through which intermolecular reactions forward and amplify extracellular signals across the cell surface has developed to occur by two mechanisms.
First, cell surface receptors can directly transduce signals by possessing both serine and threonine or simply serine in the cytoplasmic domain. They can also transmit signals through adaptor molecules through their cytoplasmic domain which bind to signalling motifs. Secondly, certain surface receptors lacking a cytoplasmic domain can transduce signals through ligand binding. Once the surface receptor binds the ligand it forms a complex with a corresponding surface receptor to regulate signalling. These categories of cell surface receptors are prominently referred to as co-receptors. Co-receptors are also referred to as accessory receptors, especially in the fields of biomedical research and immunology.
Co-receptors are proteins that maintain a three-dimensional structure. T
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https://en.wikipedia.org/wiki/Karloff%E2%80%93Zwick%20algorithm
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The Karloff–Zwick algorithm, in computational complexity theory, is a randomised approximation algorithm taking an instance of MAX-3SAT Boolean satisfiability problem as input. If the instance is satisfiable, then the expected weight of the assignment found is at least 7/8 of optimal. There is strong evidence (but not a mathematical proof) that the algorithm achieves 7/8 of optimal even on unsatisfiable MAX-3SAT instances. Howard Karloff and Uri Zwick presented the algorithm in 1997.
The algorithm is based on semidefinite programming. It can be derandomized using, e.g., the techniques from to yield a deterministic polynomial-time algorithm with the same approximation guarantees.
Comparison to random assignment
For the related MAX-E3SAT problem, in which all clauses in the input 3SAT formula are guaranteed to have exactly three literals, the simple randomized approximation algorithm which assigns a truth value to each variable independently and uniformly at random satisfies 7/8 of all clauses in expectation, irrespective of whether the original formula is satisfiable. Further, this simple algorithm can also be easily derandomized using the method of conditional expectations. The Karloff–Zwick algorithm, however, does not require the restriction that the input formula should have three literals in every clause.
Optimality
Building upon previous work on the PCP theorem, Johan Håstad showed that, assuming P ≠ NP, no polynomial-time algorithm for MAX 3SAT can achieve a p
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https://en.wikipedia.org/wiki/Glyoxal
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Glyoxal is an organic compound with the chemical formula OCHCHO. It is the smallest dialdehyde (a compound with two aldehyde groups). It is a crystalline solid, white at low temperatures and yellow near the melting point (15 °C). The liquid is yellow, and the vapor is green.
Pure glyoxal is not commonly encountered because glyoxal is usually handled as a 40% aqueous solution (density near 1.24 g/mL). It forms a series of hydrates, including oligomers. For many purposes, these hydrated oligomers behave equivalently to glyoxal. Glyoxal is produced industrially as a precursor to many products.
Production
Glyoxal was first prepared and named by the German-British chemist Heinrich Debus (1824–1915) by reacting ethanol with nitric acid.
Commercial glyoxal is prepared either by the gas-phase oxidation of ethylene glycol in the presence of a silver or copper catalyst (the Laporte process) or by the liquid-phase oxidation of acetaldehyde with nitric acid.
The first commercial glyoxal source was in Lamotte, France, started in 1960. The single largest commercial source is BASF in Ludwigshafen, Germany, at around 60,000 tons per year. Other production sites exist also in the US and China. Commercial bulk glyoxal is made and reported as a 40% solution in water by weight (approx. 1:5 molar ratio of glyoxal to water).
Laboratory methods
Glyoxal may be synthesized in the laboratory by oxidation of acetaldehyde with selenious acid or by ozonolysis of benzene.
Anhydrous glyoxal is prep
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https://en.wikipedia.org/wiki/DNA-binding%20domain
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A DNA-binding domain (DBD) is an independently folded protein domain that contains at least one structural motif that recognizes double- or single-stranded DNA. A DBD can recognize a specific DNA sequence (a recognition sequence) or have a general affinity to DNA. Some DNA-binding domains may also include nucleic acids in their folded structure.
Function
One or more DNA-binding domains are often part of a larger protein consisting of further protein domains with differing function. The extra domains often regulate the activity of the DNA-binding domain. The function of DNA binding is either structural or involves transcription regulation, with the two roles sometimes overlapping.
DNA-binding domains with functions involving DNA structure have biological roles in DNA replication, repair, storage, and modification, such as methylation.
Many proteins involved in the regulation of gene expression contain DNA-binding domains. For example, proteins that regulate transcription by binding DNA are called transcription factors. The final output of most cellular signaling cascades is gene regulation.
The DBD interacts with the nucleotides of DNA in a DNA sequence-specific or non-sequence-specific manner, but even non-sequence-specific recognition involves some sort of molecular complementarity between protein and DNA. DNA recognition by the DBD can occur at the major or minor groove of DNA, or at the sugar-phosphate DNA backbone (see the structure of DNA). Each specific type of
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https://en.wikipedia.org/wiki/Fresnel%20%28unit%29
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A fresnel is a unit of frequency equal to 1012 s−1. It was occasionally used in the field of spectroscopy, but its use has been superseded by terahertz (with the identical value 1012 hertz). It is named for Augustin-Jean Fresnel the physicist whose expertise in optics led to the creation of Fresnel lenses.
References
Units of frequency
Obsolete units of measurement
Non-SI metric units
Spectroscopy
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https://en.wikipedia.org/wiki/Attack%20model
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In cryptanalysis, attack models or attack types are a classification of cryptographic attacks specifying the kind of access a cryptanalyst has to a system under attack when attempting to "break" an encrypted message (also known as ciphertext) generated by the system. The greater the access the cryptanalyst has to the system, the more useful information they can get to utilize for breaking the cypher.
In cryptography, a sending party uses a cipher to encrypt (transform) a secret plaintext into a ciphertext, which is sent over an insecure communication channel to the receiving party. The receiving party uses an inverse cipher to decrypt the ciphertext to obtain the plaintext. A secret knowledge is required to apply the inverse cipher to the ciphertext. This secret knowledge is usually a short number or string called a key. In a cryptographic attack a third party cryptanalyst analyzes the ciphertext to try to "break" the cipher, to read the plaintext and obtain the key so that future enciphered messages can be read. It is usually assumed that the encryption and decryption algorithms themselves are public knowledge and available to the cryptographer, as this is the case for modern ciphers which are published openly. This assumption is called Kerckhoffs's principle.
Models
Some common attack models are:
Ciphertext-only attack (COA) - in this type of attack it is assumed that the cryptanalyst has access only to the ciphertext, and has no access to the plaintext. This type of
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https://en.wikipedia.org/wiki/Statistics%20Commission
|
The Statistics Commission was a non-departmental public body established in June 2000 by the UK Government to oversee the work of the Office for National Statistics.
Its chairman was Professor David Rhind who succeeded the first chairman, Sir John Kingman, in May 2003. Although it was non-departmental, the commission was funded by grant-in-aid from the Treasury. Following the implementation of the Statistics & Registration Services Act 2007, the commission was abolished. Its functions were to be taken over and considerably enhanced by the UK Statistics Authority (UKSA), whose powers began on 1 April 2008 under the chairmanship of Sir Michael Scholar. Professor Rhind is among the non-executive members of the new authority, to which the ONS is accountable. This contrasts with the duties of the previous Commission which were limited to reporting, observing and criticizing ONS while it, until 2008, has been publicly accountable via a Treasury minister.
History
The Commission arose from an election manifesto commitment by the Labour Government whilst in Opposition to provide independent national statistics. The commitment was implemented by the Government first publishing a Green Paper in 1998 inviting consultation which offered four options for overseeing the production of statistics for ministers. The subsequent white paper revealed that, of those four options, the one which received significantly more support than the others was the establishment of a Commission Consequently,
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https://en.wikipedia.org/wiki/MINTO
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MINTO (Mixed Integer Optimizer) is an integer programming solver which uses branch and bound algorithm.
MINTO is a software system that solves mixed integer programming problem by a branch and bound algorithm with linear programming relaxations. It also provides automatic constraint classification, preprocessing, primal heuristics and constraint generation. It also has inbuilt cut generation and can create knapsack cuts, GUB cuts, clique cuts, implication cuts, flow cuts, mixed integer rounding and Gomory cuts. Moreover, the user can enrich the basic algorithm by providing a variety of specialized application routines that can customize MINTO to achieve higher efficiency for a problem class.
MINTO does not have a linear programming (LP) solver of its own. It can use most of the LP solvers, like CLP, CPLEX, XPRESS through the OSI interface of COIN-OR. MINTO can read files in MPS and can also be called as a solver from AMPL. It can run on both Linux and Windows operating system. MINTO is a non-commercial solver and the executables are available for free download from its home page at COR@L.
See also
COIN-OR (Computational Infrastructure for Operations Research)
References
J.T. Linderoth and T.K. Ralphs, Noncommercial Software for Mixed-Integer Linear Programming, Integer Programming: Theory and Practice, John Karlof (ed.), CRC Press Operations Research Series, 2005, 253–303. (Working Paper Version PDF)
External links
MINTO Homepage
Mathematical optimization software
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https://en.wikipedia.org/wiki/Masp
|
MASP is an abbreviation for:
São Paulo Museum of Art (in Portuguese, Museu de Arte de São Paulo)
Mid Atlantic Star Party
MASP (protein)
MASP1 (protein)
MASP2 (protein)
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https://en.wikipedia.org/wiki/Cementoblast
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A cementoblast is a biological cell that forms from the follicular cells around the root of a tooth, and whose biological function is cementogenesis, which is the formation of cementum (hard tissue that covers the tooth root). The mechanism of differentiation of the cementoblasts is controversial but circumstantial evidence suggests that an epithelium or epithelial component may cause dental sac cells to differentiate into cementoblasts, characterised by an increase in length. Other theories involve Hertwig epithelial root sheath (HERS) being involved.
Structure
Thus cementoblasts resemble bone-forming osteoblasts but differ functionally and histologically. The cells of cementum are the entrapped cementoblasts, the cementocytes. Each cementocyte lies in its lacuna (plural, lacunae), similar to the pattern noted in bone. These lacunae also have canaliculi or canals. Unlike those in bone, however, these canals in cementum do not contain nerves, nor do they radiate outward. Instead, the canals are oriented toward the periodontal ligament (PDL) and contain cementocytic processes that exist to diffuse nutrients from the ligament because it is vascularized. The progenitor cells also found in the PDL region contribute to the mineralization of the tissue.
Once in this situation, cementoblasts lose their secretory activity and become cementocytes. However, a layer of cementoblasts is always present along the outer covering of the PDL; these cells can then produce cementum if the t
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https://en.wikipedia.org/wiki/Bragg%20plane
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In physics, a Bragg plane is a plane in reciprocal space which bisects a reciprocal lattice vector, , at right angles. The Bragg plane is defined as part of the Von Laue condition for diffraction peaks in x-ray diffraction crystallography.
Considering the adjacent diagram, the arriving x-ray plane wave is defined by:
Where is the incident wave vector given by:
where is the wavelength of the incident photon. While the Bragg formulation assumes a unique choice of direct lattice planes and specular reflection of the incident X-rays, the Von Laue formula only assumes monochromatic light and that each scattering center acts as a source of secondary wavelets as described by the Huygens principle. Each scattered wave contributes to a new plane wave given by:
The condition for constructive interference in the direction is that the path difference between the photons is an integer multiple (m) of their wavelength. We know then that for constructive interference we have:
where . Multiplying the above by we formulate the condition in terms of the wave vectors, and :
Now consider that a crystal is an array of scattering centres, each at a point in the Bravais lattice. We can set one of the scattering centres as the origin of an array. Since the lattice points are displaced by the Bravais lattice vectors, , scattered waves interfere constructively when the above condition holds simultaneously for all values of which are Bravais lattice vectors, the condition then becomes:
An
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https://en.wikipedia.org/wiki/Herman%20M%C3%BCntz
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(Chaim) Herman Müntz (28 August 1884, in Łódź – 17 April 1956, in Sweden) was a German mathematician, now remembered for the Müntz approximation theorem.
Biography
He was born in Łódź (then in the Piotrków Governorate of the Russian Empire, now in Poland) in a secular Jewish family, who had adopted a German spelling of the surname Minc. He was educated there and at the Friedrich-Wilhelms-Universität in Berlin, graduating in 1906. He wrote a doctoral dissertation there on partial differential equations and the Plateau problem, in 1910, supervised by H. A. Schwarz.
In 1911 he moved to Munich. In the following years he published on projective geometry, iterative methods, and approximation theory.
In 1914 he took a teaching position in a school near Heppenheim, and a year later another in Hochwaldhausen. He became a German citizen in 1919. At around that time he suffered a breakdown, and moved back to Poland with his wife. He shortly began publishing mathematics again. The couple moved to Göttingen in 1921, and Müntz became involved in editorial, reviewing and translation work, as well as research. At this period, and from 1924 in Berlin, he was unsuccessfully trying to get an academic position, hampered because he had not habilitated. In 1927 he worked closely with Albert Einstein.
In 1929 he took a professorial position at the Leningrad State University, where he was active in teaching, research, administration and as an editor of Lyapunov. Though he left Germany before th
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https://en.wikipedia.org/wiki/M%C3%BCntz%E2%80%93Sz%C3%A1sz%20theorem
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The Müntz–Szász theorem is a basic result of approximation theory, proved by Herman Müntz in 1914 and Otto Szász (1884–1952) in 1916. Roughly speaking, the theorem shows to what extent the Weierstrass theorem on polynomial approximation can have holes dug into it, by restricting certain coefficients in the polynomials to be zero. The form of the result had been conjectured by Sergei Bernstein before it was proved.
The theorem, in a special case, states that a necessary and sufficient condition for the monomials
to span a dense subset of the Banach space C[a,b] of all continuous functions with complex number values on the closed interval [a,b] with a > 0, with the uniform norm, is that the sum
of the reciprocals, taken over S, should diverge, i.e. S is a large set. For an interval [0, b], the constant functions are necessary: assuming therefore that 0 is in S, the condition on the other exponents is as before.
More generally, one can take exponents from any strictly increasing sequence of positive real numbers, and the same result holds. Szász showed that for complex number exponents, the same condition applied to the sequence of real parts.
There are also versions for the Lp spaces.
See also
Erdős conjecture on arithmetic progressions
References
Scanned at University of Michigan
Scanned at digizeitschriften.de
Functional analysis
Theorems in approximation theory
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https://en.wikipedia.org/wiki/F.%20and%20M.%20Riesz%20theorem
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In mathematics, the F. and M. Riesz theorem is a result of the brothers Frigyes Riesz and Marcel Riesz, on analytic measures. It states that for a measure μ on the circle, any part of μ that is not absolutely continuous with respect to the Lebesgue measure dθ can be detected by means of Fourier coefficients.
More precisely, it states that if the Fourier–Stieltjes coefficients of
satisfy
for all ,
then μ is absolutely continuous with respect to dθ.
The original statements are rather different (see Zygmund, Trigonometric Series, VII.8). The formulation here is as in Walter Rudin, Real and Complex Analysis, p.335. The proof given uses the Poisson kernel and the existence of boundary values for the Hardy space H1.
Expansions to this theorem were made by James E. Weatherbee in his 1968 dissertation: Some Extensions Of The F. And M. Riesz Theorem On Absolutely Continuous Measures.
References
F. and M. Riesz, Über die Randwerte einer analytischen Funktion, Quatrième Congrès des Mathématiciens Scandinaves, Stockholm, (1916), pp. 27-44.
Theorems in measure theory
Fourier series
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https://en.wikipedia.org/wiki/Lymphocytopenia
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Lymphocytopenia is the condition of having an abnormally low level of lymphocytes in the blood. Lymphocytes are a white blood cell with important functions in the immune system. It is also called lymphopenia. The opposite is lymphocytosis, which refers to an excessive level of lymphocytes.
Lymphocytopenia may be present as part of a pancytopenia, when the total numbers of all types of blood cells are reduced.
Classification
In some cases, lymphocytopenia can be further classified according to which kind of lymphocytes are reduced. If all three kinds of lymphocytes are suppressed, then the term is used without further qualification.
In T lymphocytopenia, there are too few T lymphocytes, but normal numbers of other lymphocytes. It causes, and manifests as, a T cell deficiency. This is usually caused by HIV infection (resulting in AIDS), but may be Idiopathic CD4+ lymphocytopenia (ICL), which is a very rare heterogeneous disorder defined by CD4+ T-cell counts below 300 cells/μL in the absence of any known immune deficiency condition, such as human immunodeficiency virus (HIV) infection or chemotherapy.
In B lymphocytopenia, there are too few B lymphocytes, but possibly normal numbers of other lymphocytes. It causes, and manifests as, a humoral immune deficiency. This is usually caused by medications that suppress the immune system.
In NK lymphocytopenia, there are too few natural killer cells, but normal numbers of other lymphocytes. This is very rare.
Causes
The most co
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https://en.wikipedia.org/wiki/ASTOS
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ASTOS is a tool dedicated to mission analysis, Trajectory optimization, vehicle design and simulation for space scenarios, i.e. launch, re-entry missions, orbit transfers, Earth observation, navigation, coverage and re-entry safety assessments. It solves Aerospace problems with a data driven interface and automatic initial guesses. Since 1989, with the support of the European Space Agency, it has developed, and improved this trajectory optimization environment to compute optimal trajectories for a variety of complex multi-phase Optimal control problems. ASTOS is being extensively used at ESA and aerospace industry community to calculate mission analysis, optimal launch and entry trajectories and was one of the tools used by ESA to assess the risk due to the ATV 'Jules Verne' re-entry. ASTOS is compatible with Windows and Linux platforms and is maintained and commercialized by Astos Solutions GmbH.
History
The development of ASTOS (formerly named ALTOS) started in 1989 at the DLR in Oberpfaffenhofen and MBB (now Astrium).
In 1991 the Institute of Flight Mechanics and Control (IFR) at the University of Stuttgart under the head of Prof. Klaus Well took the responsibility for the development of ASTOS. In 1999 the commercialization of ASTOS began. In the period 2001-2006 ASTOS was sold by Technology Transfer Initiative of the University of Stuttgart (TTI). Since September 2006, the newly founded company Astos Solutions GmbH is responsible for development and sales of ASTOS.
Proj
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https://en.wikipedia.org/wiki/Family%20Resources%20Survey
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The Family Resources Survey (FRS) is one of the United Kingdom's largest household surveys. It is carried out by the Office for National Statistics (ONS) with the National Centre for Social Research (NatCen), and Northern Ireland Statistics and Research Agency (NISRA) on an annual basis, by collecting information on the incomes and characteristics of private households in the United Kingdom. It is sponsored by the Department for Work and Pensions (DWP).
History
The survey was launched in 1992 to supply DWP with the information it required for policy analysis and it has been conducted annually since then. Before 1992, the department had to rely on other government surveys, for example the Family Expenditure Survey (now established as Living Cost and Food Survey) and the General Household Survey. However their sample sizes proved insufficient for the needs of DWP.
Beginning with a sample size of about 26,000 households, the number was reduced in 1997 to 24,000 households. After Northern Ireland was included in the sample and a 100% boost was introduced for Scotland, the sample size rose to 29,000 households in 2002 across the UK. In the most recent survey, the sample size was nearly 20,000 households.
Further changes occurred in 1998 when certain parts of the questionnaire were dropped in order to reduce the length, and in 1999 a system of rotating blocks of questions was introduced to reduce respondent fatigue. As a result, in recent years, the mean time of an interview is
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https://en.wikipedia.org/wiki/COMP128
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The COMP128 algorithms are implementations of the A3 and A8 functions defined in the GSM standard. A3 is used to authenticate the mobile station to the network. A8 is used to generate the session key used by A5 to encrypt the data transmitted between the mobile station and the BTS.
There are three versions of COMP128. They were originally confidential. A partial description of the first version was leaked in 1997 and completed via reverse engineering. This led to a full publication in 1998. The second and third versions were obtained via reverse engineering of software which verifies SIM cards compliance.
Introduction
For details on the way A3 and A8 are used see Authentication Center.
A3 and A8 both take a 128-bit key (Ki) and a 128-bit challenge (RAND) as inputs. A3 produces a 32-bit response (SRES) and A8 produces a 64-bit session key (Kc). A3/A8 is the combined function with Ki and RAND as inputs and SRES and Kc as outputs.
As A3 and A8 are not further specified, operators can freely choose the concrete algorithms used for A3 and A8.
COMP128 algorithms
The COMP128 algorithms implement the A3/A8 function. There are three of them:
COMP128-1 – original algorithm with known weaknesses
COMP128-2 – stronger algorithm which still clears the 10 rightmost bits of Kc
COMP128-3 – same algorithm as COMP128-2 with all 64 bits of Kc generated
All of them are built around a compression function with two 128 bits inputs and one 128 bits output, hence their names. Ki and RAND ar
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https://en.wikipedia.org/wiki/Robotic%20paradigm
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In robotics, a robotic paradigm is a mental model of how a robot operates. A robotic paradigm can be described by the relationship between the three basic elements of robotics: Sensing, Planning, and Acting. It can also be described by how sensory data is processed and distributed through the system, and where decisions are made.
Hierarchical/deliberative paradigm
The robot operates in a top-down fashion, heavy on planning.
The robot senses the world, plans the next action, acts; at each step the robot explicitly plans the next move.
All the sensing data tends to be gathered into one global world model.
The reactive paradigm
Sense-act type of organization.
The robot has multiple instances of Sense-Act couplings.
These couplings are concurrent processes, called behaviours, which take the local sensing data and compute the best action to take independently of what the other processes are doing.
The robot will do a combination of behaviours.
Hybrid deliberate/reactive paradigm
The robot first plans (deliberates) how to best decompose a task into subtasks (also called “mission planning”) and then what are the suitable behaviours to accomplish each subtask.
Then the behaviours starts executing as per the Reactive Paradigm.
Sensing organization is also a mixture of Hierarchical and Reactive styles; sensor data gets routed to each behaviour that needs that sensor, but is also available to the planner for construction of a task-oriented global world model.
See also
B
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https://en.wikipedia.org/wiki/Centropyge
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Centropyge is a genus of ray-finned fish, marine angelfish belonging to the family Pomacanthidae found in the Atlantic, Indian and Pacific Ocean. These species do not exceed 15 cm in length and live in haremic structures with one dominant male and multiple females. Although it is hard to identify their gender; females are often shorter and more round finned. Like many other reef fish and all marine angelfish, the species in this genus are protogynous hermaphrodite, meaning that they start their adult lives as females and the dominant individual in a group can change to a male within days. A reversal of this sex change is possible if the social status of the individual changes, it is however a process that requires much more time.
In aquaria
This genus prefer matured reef tanks due to the usually high water quality and the often used "live rock". In nature most species feed on algae, sponges and small benthic invertebrates. Having an abundance of well cured live rock will help to supplement their diet. This is also in the interest of the aquarist, as underfed Centropyge angels may nip at corals and sessile invertebrates. The difficulty of keeping varies from species to species, as does their rarity and correspondingly their price. These species are social that live in loose groups in the wild. So if multiple this genus is kept to a tank, they will establish a pecking order. To reduce the stresses of establishing the dominance in the group it is wise to choose semi-adult speci
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https://en.wikipedia.org/wiki/Wedderburn%27s%20theorem
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Wedderburn's theorem may refer to:
Artin–Wedderburn theorem, classifying semisimple rings and semisimple algebras
Wedderburn's theorem on simple rings with a unit and a minimal left ideal
Wedderburn's little theorem, that a finite domain is a commutative field
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https://en.wikipedia.org/wiki/Cherubfish
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The cherubfish (Centropyge argi), also known as the pygmy angelfish, is a species of marine ray-finned fish, a marine angelfish belonging to the family Pomacanthidae. It is found in the western Atlantic Ocean.
Description
The cherubfish has an oval, deep and laterally compressed body with a short, blunt snout and a small mouth. There is a long, robust spine at the angle of the preoperculum, which has its vertical edge being serrated. The body is deep blue in colour with the head and chest being orange-yellow with a thin blue eye ring and a small dark blue botch to the rear of the mouth. The pectoral fins are pale yellowish while the other fins are dark blue with light blue margins. The dorsal fin contains 14-15 spines and 15-16 soft rays while the anal fin has 3 spines and 17 soft rays. This species attains a maximum total length of .
Distribution
The cherubfish is found in the western Atlantic Ocean. It occurs off Bermuda, and from North Carolina through the Caribbean Sea and Gulf of Mexico to the Caribbean coast of South America, as far east as French Guiana.
Habitat and biology
The cherubfish occurs at depths between , typically below . Its usual habitat is coral rubble where it feeds on algae and small benthic invertebrates. It retreats into cavities when alarmed. It lives in small groups of around 10 fish, usually a single male and a few females and juveniles.
Systematics
The cherubfish was first formally described in 1951 by Loren Paul Woods and Robert H. Kanaza
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https://en.wikipedia.org/wiki/Krein%E2%80%93Milman%20theorem
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In the mathematical theory of functional analysis, the Krein–Milman theorem is a proposition about compact convex sets in locally convex topological vector spaces (TVSs).
This theorem generalizes to infinite-dimensional spaces and to arbitrary compact convex sets the following basic observation: a convex (i.e. "filled") triangle, including its perimeter and the area "inside of it", is equal to the convex hull of its three vertices, where these vertices are exactly the extreme points of this shape.
This observation also holds for any other convex polygon in the plane
Statement and definitions
Preliminaries and definitions
Throughout, will be a real or complex vector space.
For any elements and in a vector space, the set is called the or closed interval between and The or open interval between and is when while it is when it satisfies and The points and are called the endpoints of these interval. An interval is said to be or proper if its endpoints are distinct.
The intervals and always contain their endpoints while and never contain either of their endpoints.
If and are points in the real line then the above definition of is the same as its usual definition as a closed interval.
For any the point is said to (strictly) and if belongs to the open line segment
If is a subset of and then is called an extreme point of if it does not lie between any two points of That is, if there does exist and such that and In this articl
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https://en.wikipedia.org/wiki/Pericardial%20effusion
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A pericardial effusion is an abnormal accumulation of fluid in the pericardial cavity. The pericardium is a two-part membrane surrounding the heart: the outer fibrous connective membrane and an inner two-layered serous membrane. The two layers of the serous membrane enclose the pericardial cavity (the potential space) between them. This pericardial space contains a small amount of pericardial fluid, normally 15-50 mL in volume. The pericardium, specifically the pericardial fluid provides lubrication, maintains the anatomic position of the heart in the chest, and also serves as a barrier to protect the heart from infection and inflammation in adjacent tissues and organs.
By definition, a pericardial effusion occurs when the volume of fluid in the cavity exceeds the normal limit. If large enough, it can compress the heart, causing cardiac tamponade and obstructive shock. Some of the presenting symptoms are shortness of breath, chest pressure/pain, and malaise. Important etiologies of pericardial effusions are inflammatory and infectious (pericarditis), neoplastic, traumatic, and metabolic causes. Echocardiogram, CT and MRI are the most common methods of diagnosis, although chest X-ray and EKG are also often performed. Pericardiocentesis may be diagnostic as well as therapeutic (form of treatment).
Signs and symptoms
Pericardial effusion presentation varies from person to person depending on the size, acuity and underlying cause of the effusion. Some people may be asymptomati
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https://en.wikipedia.org/wiki/Powerex
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Powerex may refer to:
Powerex (electricity), a Vancouver-based wholesale energy marketing company and a wholly owned subsidiary of BC Hydro
Powerex Inc (semiconductors), a Pennsylvania-based semiconductor company
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https://en.wikipedia.org/wiki/MAX-3LIN-EQN
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MAX-3LIN-EQN is a problem in Computational complexity theory where the input is a system of linear equations (modulo 2). Each equation contains at most 3 variables. The problem is to find an assignment to the variables that satisfies the maximum number of equations.
This problem is closely related to the MAX-3SAT problem. It is NP-hard to approximate MAX-3LIN-EQN with ratio (1/2 - δ) for any δ > 0.
See also
PCP (complexity)
References
Rudich et al., "Computational Complexity Theory,"
IAS/Park City Mathematics Series, 2004 page 108
J. Hastad. "Some optimal inapproximability results."
In proceedings of the 29th ACM STOC, 1-10, 1997
NP-hard problems
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https://en.wikipedia.org/wiki/Ewart%27s%20sign
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Ewart's sign is a set of findings on physical examination in people with large collections of fluid around their heart (pericardial effusions).
Dullness to percussion (described historically as "woody" in quality), egophony, and bronchial breath sounds may be appreciated at the inferior angle of the left scapula when the effusion is large enough to compress the left lower lobe of the lung, causing consolidation or atelectasis.
Eponym
It was first described by William Ewart in 1896.
References
Symptoms and signs: Cardiac
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https://en.wikipedia.org/wiki/HAT%20medium
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HAT Medium (hypoxanthine-aminopterin-thymidine medium) is a selection medium for mammalian cell culture, which relies on the combination of aminopterin, a drug that acts as a powerful folate metabolism inhibitor by inhibiting dihydrofolate reductase, with hypoxanthine (a purine derivative) and thymidine (a deoxynucleoside) which are intermediates in DNA synthesis. The trick is that aminopterin blocks DNA de novo synthesis, which is absolutely required for cell division to proceed, but hypoxanthine and thymidine provide cells with the raw material to evade the blockage (the "salvage pathway"), provided that they have the right enzymes, which means having functioning copies of the genes that encode them.
The enzyme dihydrofolate reductase, which produces tetrahydrofolate (THF) by the reduction of dihydrofolate, is specifically blocked by aminopterin. THF, acting in association with specific proteins, can receive single carbon units that are then transferred to specific targets.
One of the important targets for cellular reproduction is thymidylate synthase, which creates thymidine monophosphate (TMP) from deoxyuridine monophosphate (dUMP). By additional phosphorylation reactions, TMP can be used to make thymidine triphosphate (TTP), one of the four nucleotide precursors that are used by DNA polymerases to create DNA. Without the THF required to convert dUMP, there can be no TTP, and DNA synthesis cannot proceed, unless TMP can be produced from another source. The alternative
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https://en.wikipedia.org/wiki/Beam%20stack%20search
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Beam stack search is a search algorithm that combines chronological backtracking (that is, depth-first search) with beam search and is similar to depth-first beam search. Both search algorithms are anytime algorithms that find good but likely sub-optimal solutions quickly, like beam search, then backtrack and continue to find improved solutions until convergence to an optimal solution.
Implementation
Beam stack search uses the beam stack as a data structure to integrate chronological backtracking with beam search and can be combined with the divide and conquer algorithm technique, resulting in divide-and-conquer beam-stack search.
Alternatives
Beam search using limited discrepancy backtracking (BULB) is a search algorithm that combines limited discrepancy search with beam search and thus performs non-chronological backtracking, which often outperforms the chronological backtracking done by beam stack search and depth-first beam search.
References
Search algorithms
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https://en.wikipedia.org/wiki/VIFF
|
VIFF may refer to:
Vancouver International Film Festival
Vienna Independent Film Festival
Vietnamese International Film Festival
Vilnius International Film Festival
Vectoring in forward flight, a term used in relation to the Hawker Siddeley Harrier and its derivatives
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https://en.wikipedia.org/wiki/Triple%20M%20Brisbane
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Triple M Brisbane is a commercial FM rock radio station in Brisbane, Australia. It broadcasts on the Triple M network on 104.5 MHz frequency.
Station history
Triple M Brisbane started on the FM band at 104.1 MHz on 22 August 1980. Brisbane businessman Leo Williams was the driving force behind the venture while the station manager was Rob McKay, who left the station soon after allowing program manager Ted Seymour to take the reins. Their first format was contemporary rock. It was rebranded as FM104 in December 1982 with the new slogan "Rock in Stereo", and focused on the typical Queensland lifestyle of beaches and barbecues.
Their playlists then included AC/DC, The Angels, Van Halen, ZZ Top and the Talking Heads as well as supporting Australian pub rock bands such as INXS, Hunters & Collectors and the Choirboys.
On 10 January 1982, pioneering program 'incontact,' was launched, one of the first Christian music programs to feature in ratings time (5 am-12 midnight) in Australia. The Sunday night show held the stations rating audience through to midnight and played weekly through to April 1990. Over 21 Australian premieres and the World Premiere of US rock band Whiteheart's 'Emergency Broadcast' album featured in the music as well as co-promotion of the 1987 Stryper concert at Brisbane's Festival Hall.
During 1983, they started using the popular slogans, "FM104 Rocks the Weekend", "FM104 Rocks Brisbane", and "FM104 Rock in Stereo". The first number one ratings success was in
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https://en.wikipedia.org/wiki/Div%20and%20span
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In HTML, div and span tags are elements used to define parts of a document, so that they are identifiable when a unique classification is necessary. Where other HTML elements such as p (paragraph), em (emphasis), and so on, accurately represent the semantics of the content, the additional use of span and div tags leads to better accessibility for readers and easier maintainability for authors. Where no existing HTML element is applicable, span and div can valuably represent parts of a document so that HTML attributes such as class, id, lang, or dir can be applied.
span represents an inline portion of a document, for example words within a sentence. div represents a block-level portion of a document such as a few paragraphs, or an image with its caption. div stands for division. The elements allow semantic attributes (e.g. lang="en-US"), CSS styling (e.g., color and typography), or client-side scripting (e.g., animation, hiding, and augmentation) to be applied.
div defines a 'division' of the document, a block-level item that is more distinct from elements above and below it than a span of inline material.
Examples
For example, to make a certain part of text inside a paragraph red, span can be used as follows:
History
The span element was introduced to HTML in the internationalization working group's second draft html-i18n in 1995. However, it was not until HTML 4.01 that it became part of the HTML language, appearing in the HTML 4 W3C Working Draft in 1997.
In 1995, s
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https://en.wikipedia.org/wiki/Momel
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Momel (Modelling melody) is an algorithm developed by Daniel Hirst and Robert Espesser at the CNRS Laboratoire Parole et Langage, Aix-en-Provence:
for the analysis and synthesis of intonation patterns.
Purpose
The analysis of raw fundamental frequency curves for the study of intonation needs to take into account the fact that speakers are simultaneously producing an intonation pattern and a sequence of syllables made up of segmental phones. The actual raw fundamental frequency curves which can be analysed acoustically are the result of an interaction between these two components and this makes it difficult to compare intonation patterns when they are produced with different segmental material. Compare for example the intonation patterns on the utterances It's for papa and It's for mama.
Algorithm
The Momel algorithm attempts to solve this problem by factoring the raw curves into two components:
a macromelodic component - modelled as a quadratic spline function . This is assumed to correspond to the global pitch contour of the utterance, and which is independent of the nature of the constituent phonemes. The underlying hypothesis is that this macromelodic component is, unlike raw fundamental frequency curves, both continuous and smooth. It corresponds approximately to what we produce if we hum an utterance instead of speaking it.
a micromelodic component consisting of deviations from the macromelodic curve - called a micromelodic profile. This residual curve is assumed t
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https://en.wikipedia.org/wiki/Sleeper%20Cell%20%28TV%20series%29
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Sleeper Cell is an American one-hour drama on the Showtime network that began airing on December 4, 2005. The tagline for the first season was "Friends. Neighbors. Husbands. Terrorists." and the tagline for the second season was "Cities. Suburbs. Airports. Targets." The series was nominated for an Emmy award for Outstanding Miniseries. The eight-episode second season of the series, titled Sleeper Cell: American Terror, premiered on December 10, 2006. Both seasons of Sleeper Cell were originally aired in an unusual fashion, by filming the entire season ahead of time and then airing the episodes on consecutive nights, such that each brand new season was aired for the first time over a period of less than two weeks. In Australia, both seasons originally aired on the Showtime Australia channel in 2006/2007. Re-runs as of 2008 have screened on the showcase channel (part of the Showtime Australia group of channels).
As extra material on the first season DVDs reveal, the show was originally named The Cell.
Synopsis
Darwyn Al-Sayeed, a 30-year-old American undercover FBI agent who is a Muslim and embracing Islam as his religion, is assigned to infiltrate a terrorist sleeper cell that is planning an attack in Los Angeles. The cell is run by an Arab extremist named Faris al-Farik who disguises himself as a Jew. The members of the cell come from a variety of racial backgrounds and conflicting personalities. The series also portrays the hypocrisy and dichotomy of the cell members w
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https://en.wikipedia.org/wiki/Mean%20value%20theorem%20%28divided%20differences%29
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In mathematical analysis, the mean value theorem for divided differences generalizes the mean value theorem to higher derivatives.
Statement of the theorem
For any n + 1 pairwise distinct points x0, ..., xn in the domain of an n-times differentiable function f there exists an interior point
where the nth derivative of f equals n ! times the nth divided difference at these points:
For n = 1, that is two function points, one obtains the simple mean value theorem.
Proof
Let be the Lagrange interpolation polynomial for f at x0, ..., xn.
Then it follows from the Newton form of that the highest term of is .
Let be the remainder of the interpolation, defined by . Then has zeros: x0, ..., xn.
By applying Rolle's theorem first to , then to , and so on until , we find that has a zero . This means that
,
Applications
The theorem can be used to generalise the Stolarsky mean to more than two variables.
References
Finite differences
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https://en.wikipedia.org/wiki/Cacteae
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Cacteae is a tribe of plants of the family Cactaceae found mainly in North America especially Mexico. , the internal classification of the family Cactaceae remained uncertain and subject to change. A classification incorporating many of the insights from the molecular studies was produced by Nyffeler and Eggli in 2010.
Description
The spherical to short columnar plants grow individually or in cushions. Their size varies from dwarf (Turbinicarpus) to huge (Ferocactus). The non-segmented shoot axis is ribbed (Echinocactus), warty (Coryphantha) or ribbed-warty. The size and shape of the warts ranges from long and leafy (Leuchtenbergia) to broad with flat axillae (Turbinicarpus). The areoles are usually oval, ribbon-like, grooved, or dimorphic. The small to medium-sized, regular to rarely bilaterally symmetrical flowers appear below the crown and open during the day. The fruits are fleshy to juicy berry-like, with a scaly to glabrous pericarp. They are bursting to non-bursting or simply crumbling. The small to large seeds vary in shape and surface structure of the seed coat.
Genera
The classification of cacti is in flux; the following list of genera is that from Nyffeler and Eggli (2010).
Acharagma
Ariocarpus
Astrophytum
Aztekium
Cochemiea has been split off since Nyffeler and Eggli (2010)
Coryphantha
Digitostigma
Echinocactus
Echinomastus
Epithelantha
Escobaria
Ferocactus
Geohintonia
Kroenleinia
Leuchtenbergia
Lophophora
Mammillaria –
Mammilloydia
Obrego
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https://en.wikipedia.org/wiki/B%C3%B4cher%27s%20theorem
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In mathematics, Bôcher's theorem is either of two theorems named after the American mathematician Maxime Bôcher.
Bôcher's theorem in complex analysis
In complex analysis, the theorem states that the finite zeros of the derivative of a non-constant rational function that are not multiple zeros are also the positions of equilibrium in the field of force due to particles of positive mass at the zeros of and particles of negative mass at the poles of , with masses numerically equal to the respective multiplicities, where each particle repels with a force equal to the mass times the inverse distance.
Furthermore, if C1 and C2 are two disjoint circular
regions which contain respectively all the zeros and all the poles of , then C1 and C2 also contain all the critical
points of .
Bôcher's theorem for harmonic functions
In the theory of harmonic functions, Bôcher's theorem states that a positive harmonic function in a punctured domain (an open domain minus one point in the interior) is a linear combination of a harmonic function in the unpunctured domain with a scaled fundamental solution for the Laplacian in that domain.
See also
Marden's theorem
External links
(Review of Joseph L. Walsh's book.)
Theorems in complex analysis
Harmonic functions
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https://en.wikipedia.org/wiki/Hydraulic%20power
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Hydraulic power may refer to:
Hydropower, power derived from the energy of falling or fast running water
Fluid power, use of fluids under pressure to generate, control, and transmit power
Power supplied via a Hydraulic power network, using pressurised water.
Erosive work done by hydraulic action of the sea or other water source.
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https://en.wikipedia.org/wiki/Interleukin%201-alpha
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Interleukin-1 alpha (IL-1 alpha) also known as hematopoietin 1 is a cytokine of the interleukin 1 family that in humans is encoded by the IL1A gene. In general, Interleukin 1 is responsible for the production of inflammation, as well as the promotion of fever and sepsis. IL-1α inhibitors are being developed to interrupt those processes and treat diseases.
IL-1α is produced mainly by activated macrophages, as well as neutrophils, epithelial cells, and endothelial cells. It possesses metabolic, physiological, haematopoietic activities, and plays one of the central roles in the regulation of the immune responses. It binds to the interleukin-1 receptor. It is on the pathway that activates tumor necrosis factor-alpha.
Discovery
Interleukin 1 was discovered by Gery in 1972. He named it lymphocyte-activating factor (LAF) because it was a lymphocyte mitogen. It was not until 1985 that interleukin 1 was discovered to consist of two distinct proteins, now called interleukin-1 alpha and interleukin-1 beta.
Alternative names
IL-1α is also known as fibroblast-activating factor (FAF), lymphocyte-activating factor (LAF), B-cell-activating factor (BAF), leukocyte endogenous mediator (LEM), epidermal cell-derived thymocyte-activating factor (ETAF), serum amyloid A inducer or hepatocyte-stimulating factor (HSP), catabolin, hemopoetin-1 (H-1), endogenous pyrogen (EP), and proteolysis-inducing factor (PIF).
Synthesis and structure
IL-1α is a unique member in the cytokine family in the
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https://en.wikipedia.org/wiki/Goldblade
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Goldblade are an English punk rock band from Manchester, England. The band formed in early 1995 when ex Membranes frontman, John Robb, put the band together with Wayne Simmons and former Membranes and A Witness vocalist Keith Curtis on bass, Rob Haynes (ex Houndgod and Killing for Pleasure/K.F.P.) on drums and Jay Taylor on guitar.
The band signed to Ultimate Records and released their first single, "Soul Power", before releasing several more singles and two albums - Home Turf (1996/97), and Goldblade Drop the Bomb (1998) before Simmons departed. In 2000, Goldblade then recruited a new percussionist, Martin Gray, into the line up and recorded two further singles "AC/DC" and "Who Was The Killa?" together with a third album Do You Believe In The Power Of Rock 'n' Roll all released in 2002 on a new label, Twenty Stone Blatt.
In 2001, Jay Taylor left the band to concentrate on his Bonebox project, and two new members Johny Skullknuckles and Pete 'Gorgeous' Byrchmore (ex-Nightingales, and U.K Subs) were recruited to begin work on the next album, Rebel Songs (2004). Second percussionist Gray left shortly after the recording sessions, and the album was released in 2005 on the Captain Oi! label. The band continued gigging and recording as a five-piece, with the next album Mutiny (also on Captain Oi! Records) released in 2008. Both "Rebel Songs" and "Mutiny" were also issued internationally.
Goldblade continue to tour extensively. They regularly appear at major UK music festival
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https://en.wikipedia.org/wiki/Luteolysis
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Luteolysis (also known as luteal regression) is the structural and functional degradation of the corpus luteum, which occurs at the end of the luteal phase of both the estrous and menstrual cycles in the absence of pregnancy.
Prostaglandin F2 alpha (PGF2α)
Prostaglandin F2 alpha (PGF2α) has been identified as the key luteolytic hormone in many species. PGF2α is released from uterine endometrial cells in a pulsatile pattern when stimulated by oxytocin to stimulate both luteolytic activity and further release of oxytocin from the corpus luteum.
Domestic animals
In domestic animals, luteolysis is initiated by the hormones prostaglandin F2alpha and oxytocin and is dependent on the presence of the uterus. In sheep, communication between the pars nervosa (posterior lobe of the pituitary gland), corpus luteum, and the uterus endometrium via the circulatory system is required for luteolysis. Studies with sheep have found that, if the uterine horn is ipsilateral to the ovary possessing the CL is surgically removed, the lifespan of the corpus luteum will increase drastically.
Humans/Primates
Removal of the uterus in primates (including humans) does not prolong the life of the corpus luteum. Therefore, PGF2α uterine role in regulating luteal regression has been confined to mammalian species and a different mechanism appears to control luteolysis in primates. It has been proposed that PGF2α is made locally within the ovary and the corpus luteum may be the source of luteolytic PGF2α
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https://en.wikipedia.org/wiki/Bisexual%20community
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The bisexual community, also known as the bi+, m-spec, bisexual/pansexual, or bi/pan/fluid community, includes members of the LGBT community who identify as bisexual, pansexual, omnisexual, polysexual and sexually fluid. As opposed to hetero- or homosexual people, people in the bisexual community experience attraction to more than one gender.
Defining the community
The bisexual community includes those who identify as bisexual, pansexual, omnisexual, biromantic, polysexual, or sexually fluid. Bisexual people are less likely than their lesbian and gay counterparts to be out of the closet. As a result, there is a lot of variation among the bisexual community in how important bisexual people find bisexuality or LGBT identity to their sense of self. Bisexual people may have social networks that are heavily concentrated inside the wider LGBT community; whether or not they participate in broader LGBT culture, bisexual people may also participate in bisexual-specific communities.
The bisexual community has bi-specific events and conferences; publications, such as Bi Women Quarterly; websites and organizations, like BiNet USA and the Bisexual Resource Center; magazines, such as Bi Community News; writer's groups; media, including the books Bi Any Other Name and Getting Bi; leaders and politicians, such as Robyn Ochs and Katie Hill; and mental health associations. Bisexual groups began forming in the 1980s in several cities.
These communities come together with the lesbian, gay,
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https://en.wikipedia.org/wiki/Allambie%20Reception%20Centre
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Allambie Reception Centre was a former reception, treatment, classification and transit centre for children admitted to the care of the Victorian Government in Australia. The centre operated between 1961 and 1990 and was initially managed by the Family Welfare Division of the Social Welfare Department, later the Department of Community Welfare Services and Community Services Victoria. Located at 70 Elgar Road, Burwood, Victoria, the centre was designed to accommodate up to 100 children following a breakdown in home release, foster care or a children's home placement.
History and facilities
Initially called Kildonan and managed by the Presbyterian Church, the Victorian Government purchased the institution in 1960 and managed it under the agency of the Family Welfare Division of the Social Welfare Department. The Department had responsibility for young people under two separate divisions; the Youth Welfare Division (children aged 14 to 18 years and juvenile offenders) and the Family Welfare Division (children aged 0–14 years). Opened with 90 beds for children of both sexes, Allambie was expanded to accommodate babies and toddlers when the nursery was opened in 1964. Prior to its opening, children had been housed at Turana Youth Training Centre in Parkville. The move to Allambie meant that young children of both sexes could be accommodated together.
The Education Department operated a school in the grounds of Allambie, although some children attended schools in the community.
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https://en.wikipedia.org/wiki/Phoenicochroite
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Phoenicochroite, also known as melanochroite, is a lead chromate mineral with formula Pb2OCrO4. It forms striking orange red crystals. It was first discovered in 1839 in Beryozovskoye deposit, Urals, Russia. It is named from the Greek word φοίυικος for "deep red" and χρόα for "color," in allusion to its color.
References
Lead minerals
Chromate minerals
Monoclinic minerals
Minerals in space group 12
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https://en.wikipedia.org/wiki/Statistics%20Online%20Computational%20Resource
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The Statistics Online Computational Resource (SOCR) is an online multi-institutional research and education organization. SOCR designs, validates and broadly shares a suite of online tools for statistical computing, and interactive materials for hands-on learning and teaching concepts in data science, statistical analysis and probability theory. The SOCR resources are platform agnostic based on HTML, XML and Java, and all materials, tools and services are freely available over the Internet.
The core SOCR components include interactive distribution calculators, statistical analysis modules, tools for data modeling, graphics visualization, instructional resources, learning activities and other resources.
All SOCR resources are licensed under either the Lesser GNU Public License or CC BY; peer-reviewed, integrated internally and interoperate with independent digital libraries developed by other professional societies and scientific organizations like NSDL, Open Educational Resources, Mathematical Association of America, California Digital Library, LONI Pipeline, etc.
See also
List of statistical packages
Comparison of statistical packages
External links
SOCR University of Michigan site
SOCR UCLA site
References
Educational math software
Research institutes in the United States
Statistical software
University of Michigan
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https://en.wikipedia.org/wiki/N-Methyltryptamine
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N-Methyltryptamine (NMT) is a member of the substituted tryptamine chemical class and a natural product which is biosynthesized in the human body from tryptamine by certain N-methyltransferase enzymes, such as indolethylamine N-methyltransferase. It is a common component in human urine. NMT is an alkaloid derived from L-tryptophan that has been found in the bark, shoots and leaves of several plant genera, including Virola, Acacia, Mimosa, and Desmanthus—often together with the related compounds N,N-dimethyltryptamine (DMT) and 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT).
Orally administered NMT appears to produce no psychoactive effects, likely as a result of extensive first-pass metabolism. However, it may become active upon combination with a MAOA inhibitor (MAOI).
By vaporization NMT shows activity at 50–100 mg, with a duration of 45–70 minutes; duration of visual effects 15–30 seconds. Effects are primarily non-visual.
Legality
In the United States N-Methyltryptamine is considered a schedule 1 controlled substance as an positional isomer of Alpha-methyltryptamine (AMT)
See also
N-Ethyltryptamine (NET)
N,N,-Dimethyltryptamine (DMT)
Acacia confusa (a natural source of NMT, with other tryptamines, 1.63%. Buchanan et al. 2007)
Acacia obtusifolia (NMT up to 2/3 alkaloid content)
Acacia simplicifolia (synon. A. simplex) (1.44% NMT in bark, 0.29% twigs, Pouet et al. 1976)
Desmanthus illinoensis (NMT major component seasonally)
References
External links
NMT Entry
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https://en.wikipedia.org/wiki/CRAM-MD5
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In cryptography, CRAM-MD5 is a challenge–response authentication mechanism (CRAM) based on the HMAC-MD5 algorithm. As one of the mechanisms supported by the Simple Authentication and Security Layer (SASL), it is often used in email software as part of SMTP Authentication and for the authentication of POP and IMAP users, as well as in applications implementing LDAP, XMPP, BEEP, and other protocols.
When such software requires authentication over unencrypted connections, CRAM-MD5 is preferred over mechanisms that transmit passwords "in the clear," such as LOGIN and PLAIN. However, it can't prevent derivation of a password through a brute-force attack, so it is less effective than alternative mechanisms that avoid passwords or that use connections encrypted with Transport Layer Security (TLS).
Protocol
The CRAM-MD5 protocol involves a single challenge and response cycle, and is initiated by the server:
Challenge: The server sends a base64-encoded string to the client. Before encoding, it could be any random string, but the standard that currently defines CRAM-MD5 says that it is in the format of a Message-ID email header value (including angle brackets) and includes an arbitrary string of random digits, a timestamp, and the server's fully qualified domain name.
Response: The client responds with a string created as follows.
The challenge is base64-decoded.
The decoded challenge is hashed using HMAC-MD5, with a shared secret (typically, the user's password, or a hash there
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https://en.wikipedia.org/wiki/Dinitrophenol
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Dinitrophenols are chemical compounds which are nitro derivatives of phenol.
There are six isomers of dinitrophenol:
2,3-Dinitrophenol
2,4-Dinitrophenol
2,5-Dinitrophenol
2,6-Dinitrophenol
3,4-Dinitrophenol
3,5-Dinitrophenol
Dinitrophenols also form the core structure of some herbicides, which are collectively referred to as dinitrophenol herbicides, including:
Dinofenate
Dinoprop
Dinosam
Dinoseb
Dinoterb
DNOC
Etinofen
Medinoterb
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https://en.wikipedia.org/wiki/Profilin
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Profilin is an actin-binding protein involved in the dynamic turnover and reconstruction of the actin cytoskeleton. It is found in most eukaryotic organisms. Profilin is important for spatially and temporally controlled growth of actin microfilaments, which is an essential process in cellular locomotion and cell shape changes. This restructuring of the actin cytoskeleton is essential for processes such as organ development, wound healing, and the hunting down of infectious intruders by cells of the immune system.
Profilin also binds sequences rich in the amino acid proline in diverse proteins. While most profilin in the cell is bound to actin, profilins have over 50 different binding partners. Many of those are related to actin regulation, but profilin also seems to be involved in activities in the nucleus such as mRNA splicing.
Profilin is the major allergen (via IgE) present in birch, grass, and other pollen.
Sources and distribution
Profilins are proteins of molecular weights of roughly 14–19 kDa. They are present as single genes in yeast, insects, and worms, and as multiple genes in many other organisms including plants. In mammalian cells, four profilin isoforms have been discovered; profilin-I is expressed in most tissues while profilin-II is predominant in brain and kidney.
Asgard archaea use profilins. Multiple eukaryotic diatom species lack profilins.
Profilin is essential to host cell invasion by Toxoplasma gondii. Toxoplasma profilin is the specific pathogen-
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https://en.wikipedia.org/wiki/Natural%20heritage
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Natural heritage refers to the sum total of the elements of biodiversity, including flora and fauna, ecosystems and geological structures. It forms part of our natural resources.
Definition
Heritage is that which is inherited from past generations, maintained in the present, and bestowed to future generations. The term "natural heritage", derived from "natural inheritance", pre-dates the term "biodiversity". It is a less scientific term and more easily comprehended in some ways by the wider audience interested in conservation.
The term was used in this context in the United States when Jimmy Carter set up the Georgia Heritage Trust while he was governor of Georgia; Carter's trust dealt with both natural and cultural heritage. It would appear that Carter picked the term up from Lyndon Johnson, who used it in a 1966 Message to Congress. (He may have gotten the term from his wife Lady Bird Johnson who was personally interested in conservation.) President Johnson signed the Wilderness Act of 1964.
The term "Natural Heritage" was picked up by the Science Division of The Nature Conservancy (TNC) when, under Robert E. Jenkins, Jr., it launched in 1974 what ultimately became the network of state natural heritage programs—one in each state, all using the same methodology and all supported permanently by state governments because they scientifically document conservation priorities and facilitate science-based environmental reviews. When this network was extended outside the U
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https://en.wikipedia.org/wiki/Free%20will%20theorem
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The free will theorem of John H. Conway and Simon B. Kochen states that if we have a free will in the sense that our choices are not a function of the past, then, subject to certain assumptions, so must some elementary particles. Conway and Kochen's paper was published in Foundations of Physics in 2006. In 2009, the authors published a stronger version of the theorem in the Notices of the American Mathematical Society. Later, in 2017, Kochen elaborated some details.
Axioms
The proof of the theorem as originally formulated relies on three axioms, which Conway and Kochen call "fin", "spin", and "twin". The spin and twin axioms can be verified experimentally.
Fin: There is a maximal speed for propagation of information (not necessarily the speed of light). This assumption rests upon causality.
Spin: The squared spin component of certain elementary particles of spin one, taken in three orthogonal directions, will be a permutation of (1,1,0).
Twin: It is possible to "entangle" two elementary particles and separate them by a significant distance, so that they have the same squared spin results if measured in parallel directions. This is a consequence of quantum entanglement, but full entanglement is not necessary for the twin axiom to hold (entanglement is sufficient but not necessary).
In their later 2009 paper, "The Strong Free Will Theorem", Conway and Kochen replace the Fin axiom by a weaker one called Min, thereby strengthening the theorem. The Min axiom asserts only tha
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https://en.wikipedia.org/wiki/Transgranular%20fracture
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Definition
Transgranular fracture is a type of fracture that occurs through the grains or crystals of a material. In contrast to intergranular fractures, which occur when a fracture passes across grain borders, this type of fracture traverses the material's microstructure directly through individual grains. This type of fracture typically results from a combination of high stresses and material defects, such as voids or inclusions, that create a path for crack propagation through the grains. A broad range of ductile or brittle materials, including metals, ceramics, and polymers, can experience transgranular fracture. When examined under scanning electron microscopy, this type of fracture reveals cleavage steps, river patterns, feather markings, dimples and tongues. It follows the edges of lattices in a granular material, ignoring the grains in the individual lattices. This results in a fairly smooth looking fracture with fewer sharp edges than one that follows the changing grains. This can be visualized as several wooden jigsaw puzzle pieces with the grains showing, but with each piece having grains running in a different direction. A transgranular fracture follows the grains in the wood, not the edges of the puzzle pieces. This is opposed to an intergranular fracture.
Mechanism of Transgranular Fracture
The mechanism of transgranular fracture may vary depending on the material and surrounding conditions under which the fracture occurs. However, some general steps are t
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https://en.wikipedia.org/wiki/Barium%20titanate
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Barium titanate (BTO) is an inorganic compound with chemical formula BaTiO3. Barium titanate appears white as a powder and is transparent when prepared as large crystals. It is a ferroelectric, pyroelectric, and piezoelectric ceramic material that exhibits the photorefractive effect. It is used in capacitors, electromechanical transducers and nonlinear optics.
Structure
The solid exists in one of four polymorphs depending on temperature. From high to low temperature, these crystal symmetries of the four polymorphs are cubic, tetragonal, orthorhombic and rhombohedral crystal structure. All of these phases exhibit the ferroelectric effect apart from the cubic phase. The high temperature cubic phase is easiest to describe, as it consists of regular corner-sharing octahedral TiO6 units that define a cube with O vertices and Ti-O-Ti edges. In the cubic phase, Ba2+ is located at the center of the cube, with a nominal coordination number of 12. Lower symmetry phases are stabilized at lower temperatures and involve movement of the Ti4+ to off-center positions. The remarkable properties of this material arise from the cooperative behavior of the Ti4+ distortions.
Above the melting point, the liquid has a remarkably different local structure to the solid forms, with the majority of Ti4+ coordinated to four oxygen, in tetrahedral TiO4 units, which coexist with more highly coordinated units.
Production and handling properties
Barium titanate can be synthesized by the relativel
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https://en.wikipedia.org/wiki/Symmetric%20derivative
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In mathematics, the symmetric derivative is an operation generalizing the ordinary derivative. It is defined as
The expression under the limit is sometimes called the symmetric difference quotient. A function is said to be symmetrically differentiable at a point x if its symmetric derivative exists at that point.
If a function is differentiable (in the usual sense) at a point, then it is also symmetrically differentiable, but the converse is not true. A well-known counterexample is the absolute value function , which is not differentiable at , but is symmetrically differentiable here with symmetric derivative 0. For differentiable functions, the symmetric difference quotient does provide a better numerical approximation of the derivative than the usual difference quotient.
The symmetric derivative at a given point equals the arithmetic mean of the left and right derivatives at that point, if the latter two both exist.
Neither Rolle's theorem nor the mean-value theorem hold for the symmetric derivative; some similar but weaker statements have been proved.
Examples
The absolute value function
For the absolute value function , using the notation for the symmetric derivative, we have at that
Hence the symmetric derivative of the absolute value function exists at and is equal to zero, even though its ordinary derivative does not exist at that point (due to a "sharp" turn in the curve at ).
Note that in this example both the left and right derivatives at 0 exist, but t
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https://en.wikipedia.org/wiki/Metabolic%20rift
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Metabolic rift is Karl Marx's key conception of ecological crisis tendencies under capitalism, or in Marx's own words, it is the "irreparable rift in the interdependent process of social metabolism". Marx theorized a rupture in the metabolic interaction between humanity and the rest of nature emanating from capitalist agricultural production and the growing division between town and country.
According to John Bellamy Foster, who coined the term, metabolic rift is the development of Marx's earlier work in the Economic and Philosophical Manuscripts on species-being and the relationship between humans and nature. Metabolism is Marx's "mature analysis of the alienation of nature" and presents "a more solid—and scientific—way in which to depict the complex, dynamic interchange between human beings and nature, resulting from human labor."
As opposed to those who have attributed to Marx a disregard for nature and responsibility for the environmental problems of the Soviet Union and other purportedly communist states, Foster sees in the theory of metabolic rift evidence of Marx's ecological perspective. The theory of metabolic rift "enable[ed] [Marx] to develop a critique of environmental degradation that anticipated much of present-day ecological thought", including questions of sustainability as well as the limits of agricultural production using concentrated animal feeding operations. Researchers building on the original Marxist concept have developed other similar terms like c
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https://en.wikipedia.org/wiki/Polyfuse%20%28PROM%29
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A polyfuse is a one-time-programmable memory component used in semiconductor circuits for storing unique data like chip identification numbers or memory repair data, but more usually small to medium volume production of read only memory devices or microcontroller chips. They were also used as to permit programming of Programmable Array Logic. The use of fuses allowed the device to be programmed electrically some time after it was manufactured and sealed into its packaging. Earlier fuses had to be blown using a laser at the time memory was manufactured. Polyfuses were developed to replace the earlier nickel-chromium (ni-chrome) fuses. Because ni-chrome contains nickel, the ni-chrome fuse, once blown had a tendency to grow back and render the memory unusable.
History
The first polyfuses consisted of a polysilicon line, which was programmed by applying a high (10V-15V) voltage across the device. The resultant current physically alters the device and increases its electrical resistance. This change in resistance can be detected and registered as a logical zero. An unprogrammed polyfuse would be registered as a logical one. These early devices had severe drawbacks like a high programming voltage and unreliability of the programmed devices.
Modern polyfuses
Modern polyfuses consist of a silicided polysilicon line, which is also programmed by applying a voltage across the device. Again, the resultant current permanently alters the resistance. The silicide layer covering the
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https://en.wikipedia.org/wiki/Relaxin
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Relaxin is a protein hormone of about 6000 Da, first described in 1926 by Frederick Hisaw.
The relaxin family peptide hormones belong to the insulin superfamily and consists of seven peptides of high structural but low sequence similarity; relaxin-1 (RLN1), 2 (RLN2) and 3 (RLN3), and the insulin-like (INSL) peptides, INSL3, INSL4, INSL5 and INSL6. The functions of relaxin-3, INSL4, INSL5, and INSL6 remain uncharacterised.
Synthesis
In the female, relaxin is produced by the corpus luteum of the ovary, the breast and, during pregnancy, also by the placenta, chorion, and decidua. In the male, it is produced in the prostate and is present in human semen.
Structure
Structurally, relaxin is a heterodimer of two peptide chains of 24 and 29 amino acids linked by three disulfide bridges, and it appears related to insulin.
Relaxin is produced from its prohormone, "prorelaxin", by post-translational proteolytic cleavage of its signal peptide and C domain peptide.
Function in humans
Reproduction
In females, relaxin is produced mainly by the corpus luteum, in both pregnant and nonpregnant females. Relaxin levels rise to a peak within approximately 14 days of ovulation, and then decline in the absence of pregnancy, resulting in menstruation. Relaxin may be involved in the vital process of decidualisation, working alongside steroid hormones to allow the endometrium to prepare for implantation. During the first trimester of pregnancy, levels rise and additional relaxin is produced b
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https://en.wikipedia.org/wiki/Napier-Hastings%20Urban%20Area
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The Napier-Hastings Urban Area was defined by Statistics New Zealand (Stats NZ) as a main urban area of New Zealand that was based around the twin cities of Napier and Hastings in the Hawke's Bay Region. It was defined under the New Zealand Standard Areas Classification 1992 (NZSAC92), which has since been superseded by the Statistical Standard for Geographic Areas 2018 (SSGA18).
The urban area lay mostly on the Heretaunga Plains, with part on surrounding hills. It was a city cluster consisting of the cities of Napier and Hastings, the town of Havelock North and some smaller settlements. It was the sixth-most-populous urban area in the country under the NZSAC92, with residents, fewer than Tauranga () and more than Dunedin ().
While the two cities are separated by of rural land from city edge to edge (20 km from one city centre to the next), there is sufficient economic and social integration between the cities that Stats NZ treated them as a single urban area. Stats NZ also subdivided the urban area into urban zones, as they did for the urban areas of Auckland, Hamilton and Wellington. The Napier-Hastings Urban Area contains about three-quarters of the population of the entire Hawke's Bay.
Under SSGA18, Stats NZ split up the Napier-Hastings Urban Area for statistical purposes. It was split into two "large urban areas" (30,000 to 99,999 population) of Napier and Hastings, the "medium urban area" (10,000 to 29,999) of Havelock North, the "small urban area" (1,000 to 9,999)
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https://en.wikipedia.org/wiki/Radiofrequency%20ablation
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Radiofrequency ablation (RFA), also called fulguration, is a medical procedure in which part of the electrical conduction system of the heart, tumor or other dysfunctional tissue is ablated using the heat generated from medium frequency alternating current (in the range of 350–500 kHz). RFA is generally conducted in the outpatient setting, using either local anesthetics or twilight anesthesia. When it is delivered via catheter, it is called radiofrequency catheter ablation.
Two important advantages of radio frequency current (over previously used low frequency AC or pulses of DC) are that it does not directly stimulate nerves or heart muscle and therefore can often be used without the need for general anesthesia, and that it is very specific for treating the desired tissue without significant collateral damage; due to this, it is gaining in popularity as an alternative for eligible patients who do not want to undergo surgery.
Documented benefits have led to RFA becoming widely used during the 21st century. RFA procedures are performed under image guidance (such as X-ray screening, CT scan or ultrasound) by an interventional pain specialist (such as an anesthesiologist), interventional radiologist, otolaryngologists, a gastrointestinal or surgical endoscopist, or a cardiac electrophysiologist, a subspecialty of cardiologists.
Tumors
RFA may be performed to treat tumors in the lung, liver, kidney, and bone, as well as other body organs less commonly. Once the diagnosis of t
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https://en.wikipedia.org/wiki/Pauling%27s%20rules
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Pauling's rules are five rules published by Linus Pauling in 1929 for predicting and rationalizing the crystal structures of ionic compounds.
First rule: the radius ratio rule
For typical ionic solids, the cations are smaller than the anions, and each cation is surrounded by coordinated anions which form a polyhedron. The sum of the ionic radii determines the cation-anion distance, while the cation-anion radius ratio (or ) determines the coordination number (C.N.) of the cation, as well as the shape of the coordinated polyhedron of anions.
For the coordination numbers and corresponding polyhedra in the table below, Pauling mathematically derived the minimum radius ratio for which the cation is in contact with the given number of anions (considering the ions as rigid spheres). If the cation is smaller, it will not be in contact with the anions which results in instability leading to a lower coordination number.
The three diagrams at right correspond to octahedral coordination with a coordination number of six: four anions in the plane of the diagrams, and two (not shown) above and below this plane. The central diagram shows the minimal radius ratio. The cation and any two anions form a right triangle, with , or . Then . Similar geometrical proofs yield the minimum radius ratios for the highly symmetrical cases C.N. = 3, 4 and 8.
For C.N. = 6 and a radius ratio greater than the minimum, the crystal is more stable since the cation is still in contact with six anions, but t
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https://en.wikipedia.org/wiki/Hydristor
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Hydristor is a joining of the words 'hydraulic' and 'transistor'. The
device invented by Tom Kasmer in 1996 and is based on the dual pressure balanced hydraulic vane pump invented by Harry F. Vickers in 1925.
Vane pump details
The Vickers design included an elliptic chamber which confined the radial motion of the vanes nested in the rotor slots. As the rotor and vanes turn, each vane is first pushed radially inward followed by a maximum radial extension and that happens twice per revolution. The displacement of the fixed
device is calculated by determining the difference in vane extension between minimum and maximum, times the axial length of the vanes and rotor. This multiplies to an area subject to the hydraulic pressure in the device whether used as a motor or a pump. Then an average of the minimum and maximum extensions establishes a 'radius of motion' for the pressurized equivalent pressure/force area. of each vane which passes one of the 4 axial sealing areas. What happens is that this equivalent area patch travels through the circumference or the equivalent linear distance resulting from rotating the 'radius of motion' through one complete revolution of 360 degrees.
The elliptic chamber is called a 'cam ring' by the industry. As a vane moves into, say, a maximum extension, and then rotates into a minimum extension region of the cam ring, it passes through a gradual transition from maximum to minimum followed by a gradual transition
back to maximum and this happens tw
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https://en.wikipedia.org/wiki/Statistical%20literacy
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Statistical literacy is the ability to understand and reason with statistics and data. The abilities to understand and reason with data, or arguments that use data, are necessary for citizens to understand material presented in publications such as newspapers, television, and the Internet. However, scientists also need to develop statistical literacy so that they can both produce rigorous and reproducible research and consume it. Numeracy is an element of being statistically literate and in some models of statistical literacy, or for some populations (e.g., students in kindergarten through 12th grade/end of secondary school), it is a prerequisite skill. Being statistically literate is sometimes taken to include having the abilities to both critically evaluate statistical material and appreciate the relevance of statistically-based approaches to all aspects of life in general or to the evaluating, design, and/or production of scientific work.
Promoting statistical literacy
Each day people are inundated with statistical information from advertisements ("4 out of 5 dentists recommend"), news reports ("opinion poll show the incumbent leading by four points"), and even general conversation ("half the time I don't know what you're talking about"). Experts and advocates often use numerical claims to bolster their arguments, and statistical literacy is a necessary skill to help one decide what experts mean and which advocates to believe. This is important because statistics can be
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https://en.wikipedia.org/wiki/Crystal%20Cave%2C%20Bermuda
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Crystal Cave is a cave in the British overseas territory of Bermuda. It is located in Hamilton Parish, close to Castle Harbour. The cave is approximately 500 m long, and 62 m deep. The lower 19–20 m of the cave are below water level. The cave formed at a time when the sea level was lower; as the sea level rose, many cave formations which formed above water became submerged. the crystals are igneous
A tourist attraction since 1907, it was discovered in 1905 by Carl Gibbons and Edgar Hollis, two 12-year-old boys searching for a lost cricket ball. Soon after, the Wilkinson family (the owners of the property since 1884) learned of the discovery. Mr. Percy Wilkinson lowered his 14-year-old son Bernard into it with a bicycle lamp on 140 feet of strong rope tied to a tree to explore the cave.
The area surrounding Harrington Sound (which lies to the south of Crystal Cave) is of limestone formation and is noted for its many subterranean waterways, through which the waters of the sound empty into the Atlantic Ocean. Crystal Cave is one of these, and, as its name suggests, is known for its beauty, with many stalactites, stalagmites and deep, clear pools. However, some crystal formations have been damaged by earthquakes in the distant past.
An excursion to Crystal Cave also includes the neighbouring Fantasy Cave, with Fantasy being deeper (88 steps down). Fantasy Cave was reopened in the summer of 2001 with all the pathways rebuilt and re-illuminated by artificial lighting. It was dis
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https://en.wikipedia.org/wiki/Second%20derivative
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In calculus, the second derivative, or the second-order derivative, of a function is the derivative of the derivative of . Informally, the second derivative can be phrased as "the rate of change of the rate of change"; for example, the second derivative of the position of an object with respect to time is the instantaneous acceleration of the object, or the rate at which the velocity of the object is changing with respect to time. In Leibniz notation:
where is acceleration, is velocity, is time, is position, and d is the instantaneous "delta" or change. The last expression is the second derivative of position () with respect to time.
On the graph of a function, the second derivative corresponds to the curvature or concavity of the graph. The graph of a function with a positive second derivative is upwardly concave, while the graph of a function with a negative second derivative curves in the opposite way.
Second derivative power rule
The power rule for the first derivative, if applied twice, will produce the second derivative power rule as follows:
Notation
The second derivative of a function is usually denoted . That is:
When using Leibniz's notation for derivatives, the second derivative of a dependent variable with respect to an independent variable is written
This notation is derived from the following formula:
Example
Given the function
the derivative of is the function
The second derivative of is the derivative of , namely
Relation to the graph
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https://en.wikipedia.org/wiki/Reflection%20theorem
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In algebraic number theory, a reflection theorem or Spiegelungssatz (German for reflection theorem – see Spiegel and Satz) is one of a collection of theorems linking the sizes of different ideal class groups (or ray class groups), or the sizes of different isotypic components of a class group. The original example is due to Ernst Eduard Kummer, who showed that the class number of the cyclotomic field , with p a prime number, will be divisible by p if the class number of the maximal real subfield is. Another example is due to Scholz. A simplified version of his theorem states that if 3 divides the class number of a real quadratic field , then 3 also divides the class number of the imaginary quadratic field .
Leopoldt's Spiegelungssatz
Both of the above results are generalized by Leopoldt's "Spiegelungssatz", which relates the p-ranks of different isotypic components of the class group of a number field considered as a module over the Galois group of a Galois extension.
Let L/K be a finite Galois extension of number fields, with group G, degree prime to p and L containing the p-th roots of unity. Let A be the p-Sylow subgroup of the class group of L. Let φ run over the irreducible characters of the group ring Qp[G] and let Aφ denote the corresponding direct summands of A. For any φ let q = pφ(1) and let the G-rank eφ be the exponent in the index
Let ω be the character of G
The reflection (Spiegelung) φ* is defined by
Let E be the unit group of K. We say that ε is "
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https://en.wikipedia.org/wiki/Double%20crossover
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Double crossover may refer to:
Two pairs of railway switches forming two connections that cross over between two parallel tracks
An artificial nucleic acid structural motif used in DNA nanotechnology
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https://en.wikipedia.org/wiki/Paucimorphism
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A paucimorphism is a genetic sequence variant with a rare allele frequency of 0.0005<q<0.05.
References
DNA
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https://en.wikipedia.org/wiki/Proth%27s%20theorem
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In number theory, Proth's theorem is a primality test for Proth numbers.
It states that if p is a Proth number, of the form k2n + 1 with k odd and k < 2n, and if there exists an integer a for which
then p is prime. In this case p is called a Proth prime. This is a practical test because if p is prime, any chosen a has about a 50 percent chance of working, furthermore, since the calculation is mod p, only values of a smaller than p have to be taken into consideration.
In practice, however, a quadratic nonresidue of p is found via a modified Euclid's algorithm and taken as the value of a, since if a is a quadratic nonresidue modulo p then the converse is also true, and the test is conclusive. For such an a the Legendre symbol is
Thus, in contrast to many Monte Carlo primality tests (randomized algorithms that can return a false positive), the primality testing algorithm based on Proth's theorem is a Las Vegas algorithm, always returning the correct answer but with a running time that varies randomly. Note that if a is chosen to be a quadratic nonresidue as described above, the runtime is constant, safe for the time spent on finding such a quadratic nonresidue. Finding such a value is very fast compared to the actual test.
Numerical examples
Examples of the theorem include:
for p = 3 = 1(21) + 1, we have that 2(3-1)/2 + 1 = 3 is divisible by 3, so 3 is prime.
for p = 5 = 1(22) + 1, we have that 3(5-1)/2 + 1 = 10 is divisible by 5, so 5 is prime.
for p = 13 = 3(22) +
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https://en.wikipedia.org/wiki/Acutance
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In photography, acutance describes a subjective perception of sharpness that is related to the edge contrast of an image. Acutance is related to the amplitude of the derivative of brightness with respect to space. Due to the nature of the human visual system, an image with higher acutance appears sharper even though an increase in acutance does not increase real resolution.
Historically, acutance was enhanced chemically during development of a negative (high acutance developers), or by optical means in printing (unsharp masking). In digital photography, onboard camera software and image postprocessing tools such as Photoshop or GIMP offer various sharpening facilities, the most widely used of which is known as "unsharp mask" because the algorithm is derived from the eponymous analog processing method.
In the example image, two light gray lines were drawn on a gray background. As the transition is instantaneous, the line is as sharp as can be represented at this resolution. Acutance in the left line was artificially increased by adding a one-pixel-wide darker border on the outside of the line and a one-pixel-wide brighter border on the inside of the line. The actual sharpness of the image is unchanged, but the apparent sharpness is increased because of the greater acutance.
Artificially increased acutance has drawbacks. In this somewhat overdone example most viewers will also be able to see the borders separately from the line, which create two halos around the line, one d
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https://en.wikipedia.org/wiki/Sum%20of%20normally%20distributed%20random%20variables
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In probability theory, calculation of the sum of normally distributed random variables is an instance of the arithmetic of random variables.
This is not to be confused with the sum of normal distributions which forms a mixture distribution.
Independent random variables
Let X and Y be independent random variables that are normally distributed (and therefore also jointly so), then their sum is also normally distributed. i.e., if
then
This means that the sum of two independent normally distributed random variables is normal, with its mean being the sum of the two means, and its variance being the sum of the two variances (i.e., the square of the standard deviation is the sum of the squares of the standard deviations).
In order for this result to hold, the assumption that X and Y are independent cannot be dropped, although it can be weakened to the assumption that X and Y are jointly, rather than separately, normally distributed. (See here for an example.)
The result about the mean holds in all cases, while the result for the variance requires uncorrelatedness, but not independence.
Proofs
Proof using characteristic functions
The characteristic function
of the sum of two independent random variables X and Y is just the product of the two separate characteristic functions:
of X and Y.
The characteristic function of the normal distribution with expected value μ and variance σ2 is
So
This is the characteristic function of the normal distribution with expected value an
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https://en.wikipedia.org/wiki/Pascal/MT%2B
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Pascal/MT+ was an ISO 7185 compatible Pascal compiler written in 1980 by Michael Lehman, founder of MT MicroSYSTEMS of Solana Beach, California. The company was acquired by Digital Research in 1981 which subsequently distributed versions that ran on the 8080/Z80 processor under the CP/M operating system. Later versions ran on the 68000 CPU under CP/M-68K, and the 8086 CPU under CP/M-86 and MS-DOS.
Pascal/MT+, for the 8086, was available for CP/M-86, PC DOS/MS-DOS as well as RMX-86 (a proprietary OS from Intel). Pascal/MT+86 still runs today on even the latest version of Microsoft Windows and DR-DOS.
External links
Pascal/MT+ Language Manuals
Pascal/MT+ Binaries for CP/M
CP/M software
Pascal (programming language) compilers
Pascal programming language family
1980 software
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https://en.wikipedia.org/wiki/GNU%20Pascal
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GNU Pascal (GPC) is a Pascal compiler composed of a frontend to GNU Compiler Collection (GCC), similar to the way Fortran and other languages were added to GCC. GNU Pascal is ISO 7185 compatible, and it implements most of the ISO 10206 Extended Pascal standard.
The major advantage of piggybacking GNU Pascal on the GCC compiler is that it is instantly portable to any platform the GCC compiler supports. However since GPC is a frontend, it does have to adapt if major changes are done to GCC (like a major new version). Typically, new major versions are adopted only slowly (still mostly at 3.x, with 4.x experimental builds). This is probably one of the reasons why developers are looking at a C targeting backend.
In July 2010 a developer publicly asked opinion (it vanished from the web between July 2014 and June 2015) on the future of GNU Pascal, due to developer shortage and maintenance issues as a GCC port. There was a lively discussion on the maillist where the developers seemed to lean towards reimplementing in C++ with a C code generating backend. The maillist went to sleep again, and no further releases or announcements about the future course of the project have been made.
Dev-Pascal is a graphical IDE that supports GNU Pascal.
See also
Free Pascal
External links
Git repo of one of the GPC developers.
The GNU Pascal (GPC) website
Standard Pascal – Resources and history of original, standard Pascal
Pascal User's Group Newsletters – An early Pascal history resou
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https://en.wikipedia.org/wiki/Apelin
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Apelin (also known as APLN) is a peptide that in humans is encoded by the APLN gene. Apelin is one of two endogenous ligands for the G-protein-coupled APJ receptor that is expressed at the surface of some cell types. It is widely expressed in various organs such as the heart, lung, kidney, liver, adipose tissue, gastrointestinal tract, brain, adrenal glands, endothelium, and human plasma.
Discovery
Apelin is a peptide hormone that was identified in 1998 by Masahiko Fujino and his colleagues at Gunma University and Takeda Pharmaceutical Company. In 2013, a second peptide hormone named Elabela was found by Bruno Reversade to also act as an endogenous ligand to the APLNR.
Biosynthesis
The apelin gene encodes a pre-proprotein of 77 amino acids, with a signal peptide in the N-terminal region. After translocation into the endoplasmic reticulum and cleavage of the signal peptide, the proprotein of 55 amino acids may generate several active fragments: a 36 amino acid peptide corresponding to the sequence 42-77 (apelin 36), a 17 amino acid peptide corresponding to the sequence 61-77 (apelin 17) and a 13 amino acid peptide corresponding to the sequence 65-77 (apelin 13). This latter fragment may also undergo a pyroglutamylation at the level of its N-terminal glutamine residue. However the presence and/or the concentrations of those peptides in human plasma has been questioned. Recently, 46 different apelin peptides ranging from apelin 55 () to apelin 12 have been identified in bo
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https://en.wikipedia.org/wiki/Erythroblastopenia
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Erythroblastopenia (a decrease of red blood cells in a complete blood count) may refer to:
Acquired pure red cell aplasia
Transient erythroblastopenia of childhood
See also
Polycythemia
Anemia
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https://en.wikipedia.org/wiki/Guaiazulene
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Guaiazulene, also azulon or 1,4-dimethyl-7-isopropylazulene, is a dark blue crystalline hydrocarbon. A derivative of azulene, guaiazulene is a bicyclic sesquiterpene that is a constituent of some essential oils, mainly oil of guaiac and chamomile oil, which also serve as its commercial sources. Various soft corals also contain guaiazulene as a principal pigment. Its low melting point makes guaiazulene difficult to handle, in contrast to the crystalline nature of the parent azulene. The electronic structure (and colors) of guaiazulene and azulene are very similar.
Applications
Guaiazulene is an U.S. FDA-approved cosmetic color additive. It – or its 3-sulfonate – is a component of some skin care products together with other skin soothing compounds such as allantoin.
Guaiazulene has applications as a volatile dye with a known evaporation rate to indicate end of use of various products (such as insecticide strips).
References
Cosmetics chemicals
Sesquiterpenes
Azulenes
Ophthalmology drugs
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https://en.wikipedia.org/wiki/Landau%20prime%20ideal%20theorem
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In algebraic number theory, the prime ideal theorem is the number field generalization of the prime number theorem. It provides an asymptotic formula for counting the number of prime ideals of a number field K, with norm at most X.
Example
What to expect can be seen already for the Gaussian integers. There for any prime number p of the form 4n + 1, p factors as a product of two Gaussian primes of norm p. Primes of the form 4n + 3 remain prime, giving a Gaussian prime of norm p2. Therefore, we should estimate
where r counts primes in the arithmetic progression 4n + 1, and r′ in the arithmetic progression 4n + 3. By the quantitative form of Dirichlet's theorem on primes, each of r(Y) and r′(Y) is asymptotically
Therefore, the 2r(X) term dominates, and is asymptotically
General number fields
This general pattern holds for number fields in general, so that the prime ideal theorem is dominated by the ideals of norm a prime number. As Edmund Landau proved in , for norm at most X the same asymptotic formula
always holds. Heuristically this is because the logarithmic derivative of the Dedekind zeta-function of K always has a simple pole with residue −1 at s = 1.
As with the Prime Number Theorem, a more precise estimate may be given in terms of the logarithmic integral function. The number of prime ideals of norm ≤ X is
where cK is a constant depending on K.
See also
Abstract analytic number theory
References
Theorems in analytic number theory
Theorems in algebraic
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https://en.wikipedia.org/wiki/Pixel%20%28webcomic%29
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Pixel is a webcomic written by Chris Dlugosz, first published on June 14, 2002. It is set in the aptly named "pixel universe", inhabited by pixels, voxels, vectors, plasmas (a satire on the plasma screens used by Apple computers), and polygons. The comic is known for its very literal sense of humor, and its constant breaks of the fourth wall. The text of the comic is written entirely in upper case with very little punctuation other than the occasional hyphen or exclamation point. Each comic comes with a short note, usually split into three lines at seemingly arbitrary points. These are also written in capitals with no punctuation, and usually explain or expand upon the strip.
Material from Pixel is included in Attitude 3: The New Subversive Online Cartoonists.
Development
Chris Dlugosz initially started Pixel in 2002 as a response to sprite comics, which were proliferating at the time. In an interview in 2006, Dlugosz stated that he began posting Pixel as a "casual gag" to make fun of the sprite comic genre, and that the logistics of his Pixel universe expanded over time. Dlugosz was primarily inspired by Calvin and Hobbes, which he described as "the sole reason [he] was not afraid to occasionally get rhetorical or philosophical in some of [his] own strips." Dlugosz was introduced to the webcomic format by Penny Arcade, which he also listed as an influence. His visual style, however, is entirely different, as the world of Pixel is populated with anthropomorphic geometric sh
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