source stringlengths 31 227 | text stringlengths 9 2k |
|---|---|
https://en.wikipedia.org/wiki/Mittag-Leffler%20polynomials | In mathematics, the Mittag-Leffler polynomials are the polynomials gn(x) or Mn(x) studied by .
Mn(x) is a special case of the Meixner polynomial Mn(x;b,c) at b = 0, c = -1.
Definition and examples
Generating functions
The Mittag-Leffler polynomials are defined respectively by the generating functions
and
They also have the bivariate generating function
Examples
The first few polynomials are given in the following table. The coefficients of the numerators of the can be found in the OEIS, though without any references, and the coefficients of the are in the OEIS as well.
{| class="wikitable"
!n !! gn(x) !! Mn(x)
|-
| 0 || ||
|-
| 1 || ||
|-
| 2 || ||
|-
| 3 || ||
|-
| 4 || ||
|-
| 5 || ||
|-
| 6 || ||
|-
| 7 || ||
|-
| 8 || ||
|-
| 9 || ||
|-
| 10 || ||
|}
Properties
The polynomials are related by and we have for . Also .
Explicit formulas
Explicit formulas are
(the last one immediately shows , a kind of reflection formula), and
, which can be also written as
, where denotes the falling factorial.
In terms of the Gaussian hypergeometric function, we have
Reflection formula
As stated above, for , we have the reflection formula .
Recursion formulas
The polynomials can be defined recursively by
, starting with and .
Another recursion formula, which produces an odd one from the preceding even ones and vice versa, is
, again starting with .
As for the , we have several different recursion formulas:
Concerning recursion formula (3), the polynomial is the unique polynomial solution of the difference equation , normalized so that . Further note that (2) and (3) are dual to each other in the sense that for , we can apply the reflection formula to one of the identities and then swap and to obtain the other one. (As the are polynomials, the validity extends from natural to all real values of .)
Initial values
The table of the initial values of (these values are also called the "figurate numbers for the n-dimens |
https://en.wikipedia.org/wiki/Fair%20Trade%20Certified%20Mark | The Fair Trade Certified Mark is a fair trade certification mark used primarily in the United States and Canada. It appears on products as an independent guarantee that disadvantaged producers in the developing world are getting a better deal. The Fair Trade Certified Mark is the North American equivalent of the International Fairtrade Certification Mark used in Europe, Africa, Asia, Australia and New Zealand.
For a product to carry either Certification Marks, it must come from Fair Trade USA inspected and certified producer organizations. The crops must be grown and harvested in accordance with the fair trade standards set by Fair Trade USA. Some of the supply chains are also monitored by FLO-CERT to ensure the integrity of labelled products. Only Fair Trade USA (formerly "TransFair USA") licensees can use the Fair Trade Certified Mark on their products.
The Fair Trade Certified Mark in the United States was introduced by TransFair USA on the American market in 1998.
In 2012 a variation of the US Fair Trade certification mark was adopted with the benefit of being registered globally as a trade mark. The mark is designed to pop better on the shelf through a far simpler design and the use of color. The one basket with outstretched hands indicates sharing and a "give and take" between producers and purchases. The green signals the environmental strength of Fair Trade. |
https://en.wikipedia.org/wiki/AND%20gate | The AND gate is a basic digital logic gate that implements logical conjunction (∧) from mathematical logic AND gate behaves according to the truth table. A HIGH output (1) results only if all the inputs to the AND gate are HIGH (1). If not all inputs to the AND gate are HIGH, LOW output results. The function can be extended to any number of inputs.
Symbols
There are three symbols for AND gates: the American (ANSI or 'military') symbol and the IEC ('European' or 'rectangular') symbol, as well as the deprecated DIN symbol. Additional inputs can be added as needed. For more information see Logic gate symbols article. It can also be denoted as symbol "^" or "&".
The AND gate with inputs A and B and output C implements the logical expression . This expression also may be denoted as or .
Implementations
An AND gate can be designed using only N-channel (pictured) or P-channel MOSFETs, but is usually implemented with both (CMOS). The digital inputs a and b cause the output F to have the same result as the AND function. AND gates may be made from discrete components and are readily available as integrated circuits in several different logic families.
Analytical representation
is the analytical representation of AND gate:
Alternatives
If no specific AND gates are available, one can be made from NAND or NOR gates, because NAND and NOR gates are "universal gates" meaning that they can be used to make all the others.
See also
OR gate
NOT gate
NAND gate
NOR gate
XOR gate
XNOR gate
IMPLY gate
Boolean algebra
Logic gate |
https://en.wikipedia.org/wiki/Lactarius%20indigo | Lactarius indigo, commonly known as the indigo milk cap, indigo milky, the indigo (or blue) lactarius, or the blue milk mushroom, is a species of agaric fungus in the family Russulaceae. It is a widely distributed species, growing naturally in eastern North America, East Asia, and Central America; it has also been reported in southern France. L. indigo grows on the ground in both deciduous and coniferous forests, where it forms mycorrhizal associations with a broad range of trees. The fruit body color ranges from dark blue in fresh specimens to pale blue-gray in older ones. The milk, or latex, that oozes when the mushroom tissue is cut or broken — a feature common to all members of the genus Lactarius — is also indigo blue, but slowly turns green upon exposure to air. The cap has a diameter of , and the stem is tall and thick. It is an edible mushroom, and is sold in rural markets in China, Guatemala, and Mexico. In Honduras, the mushroom is called a chora, and is generally eaten with egg; generally as a side dish for a bigger meal.
Taxonomy and nomenclature
Originally described in 1822 as Agaricus indigo by American mycologist Lewis David de Schweinitz, the species was later transferred to the genus Lactarius in 1838 by the Swede Elias Magnus Fries. German botanist Otto Kuntze called it Lactifluus indigo in his 1891 treatise Revisio Generum Plantarum, but the suggested name change was not adopted by others. Hesler and Smith, in their 1960 study of North American species of Lactarius, defined L. indigo as the type species of subsection Caerulei, a group characterized by blue latex and a sticky, blue cap. In 1979, they revised their opinions on the organization of subdivisions in the genus Lactarius, and instead placed L. indigo in subgenus Lactarius based on the color of latex and the subsequent color changes observed after exposure to air. As they explained:The gradual development of blue to violet pigmentation as one progresses from species to species is an int |
https://en.wikipedia.org/wiki/Clinical%20formulation | A clinical formulation, also known as case formulation and problem formulation, is a theoretically-based explanation or conceptualisation of the information obtained from a clinical assessment. It offers a hypothesis about the cause and nature of the presenting problems and is considered an adjunct or alternative approach to the more categorical approach of psychiatric diagnosis. In clinical practice, formulations are used to communicate a hypothesis and provide framework for developing the most suitable treatment approach. It is most commonly used by clinical psychologists and is deemed to be a core component of that profession. Mental health nurses, social workers, and some psychiatrists may also use formulations.
Types of formulation
Different psychological schools or models utilize clinical formulations, including cognitive behavioral therapy (CBT) and related therapies: systemic therapy, systemic hypothesising, psychodynamic therapy, and applied behavior analysis. The structure and content of a clinical formulation is determined by the psychological model. Most systems of formulation contain the following broad categories of information: symptoms and problems; precipitating stressors or events; predisposing life events or stressors; and an explanatory mechanism that links the preceding categories together and offers a description of the precipitants and maintaining influences of the person's problems.
Behavioral case formulations used in applied behavior analysis and behavior therapy are built on a rank list of problem behaviors, from which a functional analysis is conducted, sometimes based on relational frame theory. Such functional analysis is also used in third-generation behavior therapy or clinical behavior analysis such as acceptance and commitment therapy and functional analytic psychotherapy. Functional analysis looks at setting events (ecological variables, history effects, and motivating operations), antecedents, behavior chains, the problem behavi |
https://en.wikipedia.org/wiki/Accurate%20Miniatures | Accurate Miniatures is an American manufacturer of scale plastic model kits. It is owned by Collins-Habovick, LLC and is located in Concord, North Carolina, United States. Their products primarily consist plastic model airplane kits from World War II, though they also make model kits of planes and automobiles from other eras.
History
The original Accurate Miniatures was a Charlotte, North Carolina based plastic model company that began business in the mid-1990s. They filed for bankruptcy in June 2001. Later that year, Accurate Miniatures was purchased from the original owners by Hobby Investors LLC, now called Collins-Habovick, LLC. The transfer included the sale of the company name, logo, inventory, and intellectual property. Paul Bedford, former general manager of the original Accurate Miniatures, claims the deal was part cash and part debt assumption.
In July 2001, Accurate Miniatures, in an attempt to get out of debt, prepared to sell as much as 70% of their tooling (model molds) to the Bologna, Italy based Italeri. Some of the molds included molds for the Avenger, Dauntless, Grumman F3F, Mustang, Stormovik, and Yak kits. However, the sale to Hobby Investors LLC nullified this deal.
Unseen to Collins-Habovick was the financial disaster left by the previous management. When the previous management ceased operation, substantial debt remained behind. Mold sets like the B-25 and F-3F were not paid off completely, and mold commitments for the NASCAR stock car, SB2U, and an R-4 were not funded at all even though a fair amount of tooling had been complete. All of this (not including unpaid artists, printers, and many others) had to be overcome before anything else could be achieved.
Only through the diligent work and patience of the small staff was Accurate Miniatures able to be resurrected to become a successful company that is praised by model builders for their high-quality kits and attention to detail.
Product lines
Aircraft
Accurate Miniatures produces model |
https://en.wikipedia.org/wiki/Senckenberg%20Nature%20Research%20Society | The Senckenberg Nature Research Society (, until 2008 Senckenbergische Naturforschende Gesellschaft) is a German scholarly society with headquarters in Frankfurt am Main.
Overview
Its purpose is to conduct research in the natural sciences and make the results of nature research available to the public. The society was founded by Frankfurt citizens on 22 November 1817 on the initiative of Johann Wolfgang von Goethe, and is named for the physician, naturalist, botanist and philanthropist Johann Christian Senckenberg (1707–1772).
It shares the Senckenberg name with the , founded by Senckenberg in 1763, but is a separate organisation. The Senckenberg Nature Research Society owns several research institutes and museums, such as the Naturmuseum Senckenberg and the Naturkundemuseum Görlitz.
See also
Archiv für Molluskenkunde, one of its academic journals |
https://en.wikipedia.org/wiki/Hydrological%20transport%20model | An hydrological transport model is a mathematical model used to simulate the flow of rivers, streams, groundwater movement or drainage front displacement, and calculate water quality parameters. These models generally came into use in the 1960s and 1970s when demand for numerical forecasting of water quality and drainage was driven by environmental legislation, and at a similar time widespread access to significant computer power became available. Much of the original model development took place in the United States and United Kingdom, but today these models are refined and used worldwide.
There are dozens of different transport models that can be generally grouped by pollutants addressed, complexity of pollutant sources, whether the model is steady state or dynamic, and time period modeled. Another important designation is whether the model is distributed (i.e. capable of predicting multiple points within a river) or lumped. In a basic model, for example, only one pollutant might be addressed from a simple point discharge into the receiving waters. In the most complex of models, various line source inputs from surface runoff might be added to multiple point sources, treating a variety of chemicals plus sediment in a dynamic environment including vertical river stratification and interactions of pollutants with in-stream biota. In addition watershed groundwater may also be included. The model is termed "physically based" if its parameters can be measured in the field.
Often models have separate modules to address individual steps in the simulation process. The most common module is a subroutine for calculation of surface runoff, allowing variation in land use type, topography, soil type, vegetative cover, precipitation and land management practice (such as the application rate of a fertilizer). The concept of hydrological modeling can be extended to other environments such as the oceans, but most commonly (and in this article) the subject of a river watershed is |
https://en.wikipedia.org/wiki/A%20B%20Wood%20Medal | The A B Wood Medal is a prize awarded annually by the Institute of Acoustics for "distinguished contributions to the application of underwater acoustics". The prize, named after Albert Beaumont Wood, is presented in alternate years to European and North American scientists.
Recipients
Source: Institute of Acoustics
See also
List of physics awards |
https://en.wikipedia.org/wiki/Curtis%E2%80%93Hedlund%E2%80%93Lyndon%20theorem | The Curtis–Hedlund–Lyndon theorem is a mathematical characterization of cellular automata in terms of their symbolic dynamics. It is named after Morton L. Curtis, Gustav A. Hedlund, and Roger Lyndon; in his 1969 paper stating the theorem, Hedlund credited Curtis and Lyndon as co-discoverers. It has been called "one of the fundamental results in symbolic dynamics".
The theorem states that a function from a shift space to itself represents the transition function of a one-dimensional cellular automaton if and only if it is continuous (with respect to the Cantor topology) and equivariant (with respect to the shift map). More generally, it asserts that the morphisms between any two shift spaces (that is, continuous mappings that commute with the shift) are exactly those mappings which can be defined uniformly by a local rule.
The version of the theorem in Hedlund's paper applied only to one-dimensional finite automata, but a generalization to higher dimensional integer lattices was soon afterwards published by , and it can be even further generalized from lattices to discrete groups. One important consequence of the theorem is that, for reversible cellular automata, the reverse dynamics of the automaton can also be described by a cellular automaton.
Definitions
An alphabet is any finite set of symbols, which may be thought of as the states of the cells in a cellular automaton. A configuration is a bi-infinite sequence of symbols from the alphabet:
.
A position in a configuration is an integer, the index of one of the symbols in the sequence; the positions may be thought of as the cells of a cellular automaton. A pattern is a finite set of positions and an assignment of symbols to each of these positions.
The shift space is the set of all possible configurations over a given alphabet. It may be given the structure of a topological space according to the Cantor topology, in which the fundamental open sets are the sets of configurations that match any single pattern an |
https://en.wikipedia.org/wiki/Summation%20check | In telecommunication, the term summation check (sum check) has the following meanings:
A checksum based on the formation of the sum of the digits of a numeral.
Note: The sum of the individual digits is usually compared with a previously computed value.
A comparison of checksums on the same data on different occasions or on different representations of the data in order to verify data integrity. |
https://en.wikipedia.org/wiki/Distance%20transform | A distance transform, also known as distance map or distance field, is a derived representation of a digital image. The choice of the term depends on the point of view on the object in question: whether the initial image is transformed into another representation, or it is simply endowed with an additional map or field.
Distance fields can also be signed, in the case where it is important to distinguish whether the point is inside or outside of the shape.
The map labels each pixel of the image with the distance to the nearest obstacle pixel. A most common type of obstacle pixel is a boundary pixel in a binary image. See the image for an example of a Chebyshev distance transform on a binary image.
Usually the transform/map is qualified with the chosen metric. For example, one may speak of Manhattan distance transform, if the underlying metric is Manhattan distance. Common metrics are:
Euclidean distance
Taxicab geometry, also known as City block distance or Manhattan distance.
Chebyshev distance
There are several algorithms to compute the distance transform for these different distance metrics, however the computation of the exact Euclidean distance transform (EEDT) needs special treatment if it is computed on the image grid. Recently, distance transform computation has also been proposed using a static Schrodinger's equation. This particular approach has the benefit of obtaining an analytical closed-form solution to distance transforms, and of computing the average distance transform over a set of distance transforms, owing to the linearity of the Schrödinger equation. Further, this approach has also been leveraged to extend distance transforms to line-segments and curves.
Applications are digital image processing (e.g., blurring effects, skeletonizing), motion planning in robotics, medical-image analysis for prenatal genetic testing, and even pathfinding.
Uniformly-sampled signed distance fields have been used for GPU-accelerated font smoothing, for exam |
https://en.wikipedia.org/wiki/Luteuthis%20shuishi | Luteuthis shuishi is a species of octopus that lives in the South China Sea, which is known only from one female specimen collected at a depth of 767 meters. It has short arms and is quite gelatinous. The octopus's total length is about 300 millimeters. |
https://en.wikipedia.org/wiki/Light%20Scattering%20Spectroscopy | Light scattering spectroscopy (LSS) is a spectroscopic technique typically used to evaluate morphological changes in epithelial cells in order to study mucosal tissue and detect early cancer and precancer.
Light scattering spectroscopy relies upon elastic scattering of photons reflected from the epithelium. Most of the signal is generated by light scattering from small intracellular structures, but larger intracellular structures, such as nuclei, also scatter light, with their relative contribution increasing in the backscatter direction. As changes in the morphology of epithelial cells are hallmarks of pre-cancer and early cancer, LSS can be used for early cancer diagnosis.
In addition to photons backscattering from epithelial cells, a major portion of photons penetrates the epithelium, reaching optically turbid connective tissue where they are scattered multiple times and partially absorbed by hemoglobin. As a result, it is not possible to measure single backscattering events directly in human tissue, with polarization gating and spatial gating well-suited for endoscopy applications.
History
Lev T. Perelman, principal scientist at MIT, and Vadim Backman, graduate student in Harvard- MIT Health Sciences and Technology program introduced LSS in 1998.
Applications
Light scattering spectroscopy has been applied for detection of precancer in many organs including esophagus, colon, urinary bladder, oral cavity, cervix, pancreatic cyst, stomach, skin, and bile duct. |
https://en.wikipedia.org/wiki/X86%20calling%20conventions | This article describes the calling conventions used when programming x86 architecture microprocessors.
Calling conventions describe the interface of called code:
The order in which atomic (scalar) parameters, or individual parts of a complex parameter, are allocated
How parameters are passed (pushed on the stack, placed in registers, or a mix of both)
Which registers the called function must preserve for the caller (also known as: callee-saved registers or non-volatile registers)
How the task of preparing the stack for, and restoring after, a function call is divided between the caller and the callee
This is intimately related with the assignment of sizes and formats to programming-language types.
Another closely related topic is name mangling, which determines how symbol names in the code are mapped to symbol names used by the linker. Calling conventions, type representations, and name mangling are all part of what is known as an application binary interface (ABI).
There are subtle differences in how various compilers implement these conventions, so it is often difficult to interface code which is compiled by different compilers. On the other hand, conventions which are used as an API standard (such as stdcall) are very uniformly implemented.
Historical background
Prior to microcomputers, the machine manufacturer generally provided an operating system and compilers for several programming languages. The calling convention(s) for each platform were those defined by the manufacturer's programming tools.
Early microcomputers before the Commodore Pet and Apple II generally came without an OS or compilers. The IBM PC came with Microsoft's fore-runner to Windows, the Disk Operating System (DOS), but it did not come with a compiler. The only hardware standard for IBM PC-compatible machines was defined by the Intel processors (8086, 80386) and the literal hardware IBM shipped. Hardware extensions and all software standards (save for a BIOS calling convention) were th |
https://en.wikipedia.org/wiki/ESTREAM | eSTREAM is a project to "identify new stream ciphers suitable for widespread adoption", organised by the EU ECRYPT network. It was set up as a result of the failure of all six stream ciphers submitted to the NESSIE project. The call for primitives was first issued in November 2004. The project was completed in April 2008. The project was divided into separate phases and the project goal was to find algorithms suitable for different application profiles.
Profiles
The submissions to eSTREAM fall into either or both of two profiles:
Profile 1: "Stream ciphers for software applications with high throughput requirements"
Profile 2: "Stream ciphers for hardware applications with restricted resources such as limited storage, gate count, or power consumption."
Both profiles contain an "A" subcategory (1A and 2A) with ciphers that also provide authentication in addition to encryption. In Phase 3 none of the ciphers providing authentication are being considered (The NLS cipher had authentication removed from it to improve its performance).
eSTREAM portfolio
the following ciphers make up the eSTREAM portfolio:
These are all free for any use. Rabbit was the only one that had a patent pending during the eStream competition, but it was released into the public domain in October 2008.
The original portfolio, published at the end of Phase 3, consisted of the above ciphers plus F-FCSR which was in Profile 2. However, cryptanalysis of F-FCSR led to a revision of the portfolio in September 2008 which removed that cipher.
Phases
Phase 1
Phase 1 included a general analysis of all submissions with the purpose of selecting a subset of the submitted designs for further scrutiny. The designs were scrutinized based on criteria of security, performance (with respect to the block cipher AES—a US Government approved standard, as well as the other candidates), simplicity and flexibility, justification and supporting analysis, and clarity and completeness of the documentation. Submi |
https://en.wikipedia.org/wiki/Melanoblast | A melanoblast is a precursor cell of a melanocyte. These cells migrate from the trunk neural crest cells (in terms of axial level from neck to posterior end) dorsolaterally between the ectoderm and dorsal surface of the somites.
See also
Biological pigment
List of human cell types derived from the germ layers |
https://en.wikipedia.org/wiki/G.%20H.%20Hardy | Godfrey Harold Hardy (7 February 1877 – 1 December 1947) was an English mathematician, known for his achievements in number theory and mathematical analysis. In biology, he is known for the Hardy–Weinberg principle, a basic principle of population genetics.
G. H. Hardy is usually known by those outside the field of mathematics for his 1940 essay A Mathematician's Apology, often considered one of the best insights into the mind of a working mathematician written for the layperson.
Starting in 1914, Hardy was the mentor of the Indian mathematician Srinivasa Ramanujan, a relationship that has become celebrated. Hardy almost immediately recognised Ramanujan's extraordinary albeit untutored brilliance, and Hardy and Ramanujan became close collaborators. In an interview by Paul Erdős, when Hardy was asked what his greatest contribution to mathematics was, Hardy unhesitatingly replied that it was the discovery of Ramanujan. In a lecture on Ramanujan, Hardy said that "my association with him
is the one romantic incident in my life".
Early life and career
G. H. Hardy was born on 7 February 1877, in Cranleigh, Surrey, England, into a teaching family. His father was Bursar and Art Master at Cranleigh School; his mother had been a senior mistress at Lincoln Training College for teachers. Both of his parents were mathematically inclined, though neither had a university education.
Hardy's own natural affinity for mathematics was perceptible at an early age. When just two years old, he wrote numbers up to millions, and when taken to church he amused himself by factorising the numbers of the hymns.
After schooling at Cranleigh, Hardy was awarded a scholarship to Winchester College for his mathematical work. In 1896, he entered Trinity College, Cambridge. After only two years of preparation under his coach, Robert Alfred Herman, Hardy was fourth in the Mathematics Tripos examination. Years later, he sought to abolish the Tripos system, as he felt that it was becoming more an e |
https://en.wikipedia.org/wiki/Anonymous%20blog | An anonymous blog is a blog without any acknowledged author or contributor. Anonymous bloggers may achieve anonymity through the simple use of a pseudonym, or through more sophisticated techniques such as layered encryption routing, manipulation of post dates, or posting only from publicly accessible computers. Motivations for posting anonymously include a desire for privacy or fear of retribution by an employer (e.g., in whistleblower cases), a government (in countries that monitor or censor online communication), or another group.
Deanonymizing techniques
Fundamentally, deanonymization can be divided into two categories:
Social correlation compares known details about a person's life with the contents of an anonymous blog to look for similarities. If the author does not attempt to conceal their identity, social correlation is a very straightforward procedure: a simple correlation between the "anonymous" blogger's name, profession, lifestyle, etc., and the known person. Even if an author generally attempts to conceal their identity (by not providing their name, location, etc.), the blog can be deanonymized by correlating seemingly innocuous, general details.
Technical identification determines the author's identity through the blog's technical details. In extreme cases, technical identification entails looking at the server logs, the Internet provider logs, and payment information associated with the domain name.
These techniques may be used together. The order of techniques employed typically escalates from the social correlation techniques, which do not require the compliance of any outside authorities (e.g., Internet providers, server providers, etc.), to more technical identification.
Types
Just as a blog can be on any subject, so can an anonymous blog. Most fall into the following major categories:
Political: A commentary on the political situation within a country, where being open may risk prosecution. Anonymous blogging can also add power to a political |
https://en.wikipedia.org/wiki/Urban%20thermal%20plume | An urban thermal plume describes rising air in the lower altitudes of the Earth's atmosphere caused by urban areas being warmer than surrounding areas. Over the past thirty years there has been increasing interest in what have been called urban heat islands (UHI), but it is only since 2007 that thought has been given to the rising columns of warm air, or ‘thermal plumes’ that they produce. Common on-shore breezes at the seaside on a warm day, and off-shore breezes at night are caused by the land heating up faster on a sunny day and cooling faster after sunset, respectively. Thermals, or warm airs, that rise from the land and sea affect the local microscale meteorology; and perhaps at times the mesometeorology. Urban thermal plumes have as powerful although less localized an effect.
London is generally 3 to 9 Celsius hotter than the Home Counties. London’s meteorological aberrations were first studied by Luke Howard, FRS in the 1810s, but the notion that this large warm area would produce a significant urban thermal plume was not seriously proposed until very recently.
Microscale thermal plumes, whose diameters may be measured in tens of metres, such as those produced by industrial chimney stacks, have been extensively investigated, but largely from the point of view of the plumes dispersal by local micrometeorology. Though their velocity is generally less, their very much greater magnitude (diameter) means that urban thermal plumes will have a more significant effect upon the mesometeorology and even continental macrometeorology.
Climate change
Decreasing Arctic sea ice cover is one of the most visible manifestations of climate change, often linked to rising global temperatures. However, there are several reports that shrinking polar ice is due more to changes in ambient wind direction than to increasing environmental temperatures per se.
In 2006-07, a team led by Son Nghiem of NASA Jet Propulsion Laboratory, Pasadena, California, studied trends in Arctic perenn |
https://en.wikipedia.org/wiki/Calgary%20Internet%20Exchange | The YYCIX Internet Exchange Community Ltd (YYCIX) in Calgary, Canada is the first Internet exchange point (IXP) in Alberta. It allows the local exchange of Internet traffic between members, staying within Canadian jurisdiction, optimizing the performance and economy of traffic flows, and limiting the potential for extra-legal surveillance.
The YYCIX follows IXP best-practices, in that it is neutral and independent, has no mandatory fees, and is supported entirely through voluntary donations. The YYCIX is incorporated as a Canadian tax-exempt non-profit corporation.
Technology
The YYCIX is currently running on a variety of Cisco equipment, supporting speeds of 1Gbit/s on copper, or 1Gbit/s to 100Gbit/s on fiber. The YYCIX provides NTP and an optional BGP route reflectors for multilateral peering.
Both IPv4 and IPv6 peering is possible and encouraged at the YYCIX.
Availability
YYCIX is currently available in the following locations in Calgary:
DataHive - Data Centre
Suite 300, 840 – 7th Avenue SW, Calgary, Alberta
Signed a Memorandum of Understanding which provides no-cost cross-connects to members inside its data centre
Colocation, many carriers, Hurricane Electric
YYCIX switch ports: 1G/10/25/40/100G SM/MM
Q9 Calgary Three - Data Centre
5300 86 Ave SE, Calgary, Alberta
Colocation, many carriers
YYCIX switch ports: 1G/10G/25G/40G/100G SM/MM
Shaw (ViaWest Calgary) - Data Centre
7007 69 Ave SE, Calgary, Alberta
Colocation, many carriers
YYCIX switch ports: 1G/10G/25G/40G/100G SM/MM
Arrow Calgary - Data Centre
330 - 840 7th Ave SW
Colocation, interconnects to Telecom
YYCIX switch ports: 1G/10/25/40/100 SM/MM
City of Calgary - City Hall
City of Calgary, 800 Macleod Trail SE, Calgary, Alberta
No colocation permitted, only provides circuit connects to YYCIX
YYCIX switch ports: 1G/10G/25G/40G/100G SM/MM
Rogers DC2
1313 10th Ave SW
Colocation, interconnects to Telecom
YYCIX switch ports: 1G/10/25/40/100 SM
See also
List of Internet exchange |
https://en.wikipedia.org/wiki/CIDNP | CIDNP (chemically induced dynamic nuclear polarization), often pronounced like "kidnip", is a nuclear magnetic resonance (NMR) technique that is used to study chemical reactions that involve radicals. It detects the non-Boltzmann (non-thermal) nuclear spin state distribution produced in these reactions as enhanced absorption or emission signals.
CIDNP was discovered in 1967 by Bargon and Fischer, and, independently, by Ward and Lawler. Early theories were based on dynamic nuclear polarisation (hence the name) using the Overhauser Effect. The subsequent experiments, however, have found that in many cases DNP fails to explain CIDNP polarization phase. In 1969 an alternative explanation which relies on the nuclear spins affecting the probability of a radical pair recombining or separating.
It is related to chemically induced dynamic electron polarization (CIDEP) insofar as the radical-pair mechanism explains both phenomena.
Concept and experimental set-up
The effect is detected by NMR spectroscopy, usually using 1H NMR spectrum, as enhanced absorption or emission signals ("negative peaks"). The effect arises when unpaired electrons (radicals) are generated during a chemical reaction involving heat or light within the NMR tube. The magnetic field in the spectrometer interacts with the magnetic fields that are caused by the spins of the protons. The two spins of protons produce two slightly different energy levels. In normal conditions, slightly more nuclei, about 10 parts in a million are found in the lower energy level. In contrast, CIDNP produces greatly imbalanced populations, with far greater numbers of spins in upper energy level in some products of the reaction and greater numbers in the lower energy level in other products. The spectrometer uses radio frequencies to detect these differences.
Radical pair mechanism
The radical pair mechanism is currently accepted as the most common cause of CIDNP. This theory was proposed by Closs, and, independently, by Kapte |
https://en.wikipedia.org/wiki/Constant%20false%20alarm%20rate | Constant false alarm rate (CFAR) detection refers to a common form of adaptive algorithm used in radar systems to detect target returns against a background of noise, clutter and interference.
Principle
In the radar receiver, the returning echoes are typically received by the antenna, amplified, down-converted to an intermediate frequency, and then passed through detector circuitry that extracts the envelope of the signal, known as the video signal. This video signal is proportional to the power of the received echo. It comprises the desired echo signal as well as the unwanted signals from internal receiver noise and external clutter and interference. The term video refers to the resulting signal being appropriate for display on a cathode ray tube, or "video screen".
The role of the constant false alarm rate circuitry is to determine the power threshold above which any return can be considered to probably originate from a target as opposed to one of the spurious sources. If this threshold is too low, more real targets will be detected, but at the expense of increased numbers of false alarms. Conversely, fewer targets will be detected if the threshold is too high, but the number of false alarms will also be low. In most radar detectors, the threshold is set to achieve a required probability of false alarm (equivalently, false alarm rate or time between false alarms).
Suppose the background against which targets are to be detected is constant with time and space. In that case, a fixed threshold level can be chosen that provides a specified probability of false alarm, governed by the probability density function of the noise, which is usually assumed to be Gaussian. The probability of detection is then a function of the signal-to-noise ratio of the target return. However, in most fielded systems, unwanted clutter and interference sources mean that the noise level changes both spatially and temporally. In this case, a changing threshold can be used, where the thresho |
https://en.wikipedia.org/wiki/Zadik%E2%80%93Barak%E2%80%93Levin%20syndrome | Zadik–Barak–Levin syndrome (ZBLS) is a congenital disorder in humans. Presenting conditions include primary hypothyroidism, cleft palate, hypodontia, and ectodermal dysplasia. It is the result of an embryonic defect in the mesodermal-ectodermal midline development.
Signs and symptoms
Diagnosis
Management |
https://en.wikipedia.org/wiki/Subclass%20%28set%20theory%29 | In set theory and its applications throughout mathematics, a subclass is a class contained in some other class in the same way that a subset is a set contained in some other set.
That is, given classes A and B, A is a subclass of B if and only if every member of A is also a member of B.
If A and B are sets, then of course A is also a subset of B.
In fact, when using a definition of classes that requires them to be first-order definable, it is enough that B be a set; the axiom of specification essentially says that A must then also be a set.
As with subsets, the empty set is a subclass of every class, and any class is a subclass of itself. But additionally, every class is a subclass of the class of all sets. Accordingly, the subclass relation makes the collection of all classes into a Boolean lattice, which the subset relation does not do for the collection of all sets. Instead, the collection of all sets is an ideal in the collection of all classes. (Of course, the collection of all classes is something larger than even a class!) |
https://en.wikipedia.org/wiki/Scombroid%20food%20poisoning | Scombroid food poisoning, also known as simply scombroid, is a foodborne illness that typically results from eating spoiled fish. Symptoms may include flushed skin, sweating, headache, itchiness, blurred vision, abdominal cramps, and diarrhea. Onset of symptoms is typically 10 to 60 minutes after eating and can last for up to two days. Rarely, breathing problems, difficulty swallowing, redness of the mouth, or an irregular heartbeat may occur.
Scombroid occurs from eating fish high in histamine due to inappropriate storage or processing. Fish commonly implicated include tuna, mackerel, mahi mahi, walu walu, sardine, anchovy, bonito, herring, bluefish, amberjack, and marlin. These fish naturally have high levels of histidine, which is converted to histamine when bacterial growth occurs during improper storage. Subsequent cooking, smoking, or freezing does not eliminate the histamine. Diagnosis is typically based on the symptoms and may be supported by a normal blood tryptase. If a number of people who eat the same fish develop symptoms, the diagnosis is more likely.
Prevention is by refrigerating or freezing fish right after it is caught. Treatment is generally with antihistamines such as diphenhydramine and ranitidine. Epinephrine may be used for severe symptoms. Along with ciguatera fish poisoning, it is one of the most common type of seafood poisoning. It occurs globally in both temperate and tropical waters. Only one death has been reported. The condition was first described in 1799.
Signs and symptoms
Symptoms typically occur within 10–30 minutes of ingesting the fish and generally are self-limited. People with asthma are more vulnerable to respiratory problems such as wheezing or bronchospasms. However, symptoms may show over two hours after eating a spoiled dish. They usually last for about 10 to 14 hours, and rarely exceed one to two days.
Initial
The first signs of poisoning suggest an allergic reaction with these symptoms:
facial flushing/sweating
b |
https://en.wikipedia.org/wiki/Nuclear%20explosive | A nuclear explosive is an explosive device that derives its energy from nuclear reactions. Almost all nuclear explosive devices that have been designed and produced are nuclear weapons intended for warfare.
Other, non-warfare, applications for nuclear explosives have occasionally been proposed. For example, nuclear pulse propulsion is a form of spacecraft propulsion that would use nuclear explosives to provide impulse to a spacecraft. A similar application is the proposal to use nuclear explosives for asteroid deflection. From 1958 to 1965 the United States government ran a project to design a nuclear explosive powered nuclear pulse rocket called Project Orion. Never built, this vessel would use repeated nuclear explosions to propel itself and was considered surprisingly practical. It is thought to be a feasible design for interstellar travel.
Nuclear explosives were once considered for use in large-scale excavation. A nuclear explosion could be used to create a harbor, or a mountain pass, or possibly large underground cavities for use as storage space. It was thought that detonating a nuclear explosive in oil-rich rock could make it possible to extract more from the deposit, e.g. note the Canadian Project Oilsand. From 1958 to 1973 the U.S. government exploded 28 nuclear test-shots in a project called Operation Plowshare. The purpose of the operation was to use peaceful nuclear explosions for moving and lifting enormous amounts of earth and rock during construction projects such as building reservoirs. The Soviet Union conducted a much more vigorous program of 122 nuclear tests, some with multiple devices, between 1965 and 1989 under the auspices of Program No. 7 – Nuclear Explosions for the National Economy.
As controlled nuclear fusion has proven difficult to use as an energy source, an alternate proposal for producing fusion power has been to detonate nuclear fusion explosives inside very large underground chambers and then using the heat produced, which woul |
https://en.wikipedia.org/wiki/Theory%20of%20Colours | Theory of Colours () is a book by Johann Wolfgang von Goethe about the poet's views on the nature of colours and how they are perceived by humans. It was published in German in 1810 and in English in 1840. The book contains detailed descriptions of phenomena such as coloured shadows, refraction, and chromatic aberration. The book is a successor to two short essays titled "Contributions to Optics" ().
The work originated in Goethe's occupation with painting and primarily had its influence in the arts, with painters such as (Philipp Otto Runge, J. M. W. Turner, the Pre-Raphaelites, Hilma af Klint, and Wassily Kandinsky).
Although Goethe's work was rejected by some physicists, a number of philosophers and physicists have concerned themselves with it, including Thomas Johann Seebeck, Arthur Schopenhauer (see: On Vision and Colors), Hermann von Helmholtz, Ludwig Wittgenstein, Werner Heisenberg, Kurt Gödel, and Mitchell Feigenbaum.
Goethe's book provides a catalogue of how colour is perceived in a wide variety of circumstances, and considers Isaac Newton's observations to be special cases. Unlike Newton, Goethe's concern was not so much with the analytic treatment of colour, as with the qualities of how phenomena are perceived. Philosophers have come to understand the distinction between the optical spectrum, as observed by Newton, and the phenomenon of human colour perception as presented by Goethe—a subject analyzed at length by Wittgenstein in his comments on Goethe's theory in Remarks on Colour.
Historical background
At Goethe's time, it was generally acknowledged that, as Isaac Newton had shown in his Opticks in 1704, colourless (white) light is split up into its component colours when directed through a prism.
Goethe's starting point was the supposed discovery of how Newton erred in the prismatic experiment, and by 1793 Goethe had formulated his arguments against Newton in the essay "Über Newtons Hypothese der diversen Refrangibilität" ("On Newton's hypoth |
https://en.wikipedia.org/wiki/ISO%202033 | The ISO 2033:1983 standard ("Coding of machine readable characters (MICR and OCR)") defines character sets for use with Optical Character Recognition or Magnetic Ink Character Recognition systems. The Japanese standard JIS X 9010:1984 ("Coding of machine readable characters (OCR and MICR)", originally designated JIS C 6229-1984) is closely related.
Character set for OCR-A
The version of the encoding for the OCR-A font registered with the ISO-IR registry as ISO-IR-91 is the Japanese (JIS X 9010 / JIS C 6229) version, which differs from the encoding defined by ISO 2033 only in the addition of a Yen sign at 5C.
Character set for OCR-B
The version of the G0 set for the OCR-B font registered with the ISO-IR registry as ISO-IR-92 is the Japanese (JIS X 9010 / JIS C 6229) version, which differs from the encoding defined by ISO 2033 only in being based on JIS-Roman (with a dollar sign at 0x24 and a Yen sign at 0x5C) rather than on the ISO 646 IRV (with a backslash at 0x5C and, at the time, a universal currency sign (¤) at 0x24). Besides those code points, it differs from ASCII only in omitting the backtick (`) and tilde (~). An additional supplementary set registered as ISO-IR-93 assigns the pound sign (£), universal currency sign (¤) and section sign (§) to their ISO-8859-1 codepoints, and the backslash to the ISO-8859-1 codepoint for the Yen sign.
Character set for JIS X 9008 (JIS C 6257)
JIS X 9010 (JIS C 6229) also defines character sets for the JIS X 9008:1981 (formerly JIS C 6257-1981) "hand-printed" OCR font. These include subsets of the JIS X 0201 Roman set (registered as ISO-IR-94 and omitting the backtick (`), lowercase letters, curly braces ({, }) and overline (‾)), and kana set (registered as ISO-IR-96 and omitting the East Asian style comma (､) and full stop (｡), the interpunct (･) and the small kana), in addition to a set (registered as ISO-IR-95) containing only the backslash, which is assigned to the same code point as in ISO-IR-93.
The JIS C 6527 fon |
https://en.wikipedia.org/wiki/List%20of%20Eritrean%20flags | This is a list of flags used in Eritrea. For more information about the national flag, visit the article Flag of Eritrea.
National flag
Governmental flag
Ethnic groups flags
Historical flags
See also
Emblem of Eritrea
Flag of Eritrea |
https://en.wikipedia.org/wiki/Computer%20%28occupation%29 | The term "computer", in use from the early 17th century (the first known written reference dates from 1613), meant "one who computes": a person performing mathematical calculations, before electronic computers became commercially available. Alan Turing described the "human computer" as someone who is "supposed to be following fixed rules; he has no authority to deviate from them in any detail." Teams of people, often women from the late nineteenth century onwards, were used to undertake long and often tedious calculations; the work was divided so that this could be done in parallel. The same calculations were frequently performed independently by separate teams to check the correctness of the results.
Since the end of the 20th century, the term "human computer" has also been applied to individuals with prodigious powers of mental arithmetic, also known as mental calculators.
Origins in sciences
Astronomers in Renaissance times used that term about as often as they called themselves "mathematicians" for their principal work of calculating the positions of planets. They often hired a "computer" to assist them. For some men, such as Johannes Kepler, assisting a scientist in computation was a temporary position until they moved on to greater advancements. Before he died in 1617, John Napier suggested ways by which "the learned, who perchance may have plenty of pupils and computers" might construct an improved logarithm table.
Computing became more organized when the Frenchman Alexis Claude Clairaut (1713–1765) divided the computation to determine the time of the return of Halley's Comet with two colleagues, Joseph Lalande and Nicole-Reine Lepaute. Human computers continued plotting the future movements of astronomical objects to create celestial tables for almanacs in the late 1760s.
The computers working on the Nautical Almanac for the British Admiralty included William Wales, Israel Lyons and Richard Dunthorne. The project was overseen by Nevil Maskelyne. Maskely |
https://en.wikipedia.org/wiki/Azure%20DevOps%20Server | Azure DevOps Server (formerly Team Foundation Server (TFS) and Visual Studio Team System (VSTS)) is a Microsoft product that provides version control (either with Team Foundation Version Control (TFVC) or Git), reporting, requirements management, project management (for both agile software development and waterfall teams), automated builds, testing and release management capabilities. It covers the entire application lifecycle and enables DevOps capabilities. Azure DevOps can be used as a back-end to numerous integrated development environments (IDEs) but is tailored for Microsoft Visual Studio and Eclipse on all platforms.
On-premises vs. online
Azure DevOps is available in two different forms: on-premises ("Server") and online ("Services"). The latter form is called Azure DevOps Services (formerly Visual Studio Online before it was renamed to Visual Studio Team Services in 2015). The cloud service is backed by the Microsoft Azure cloud platform. It uses the same code as the on-premises version of Azure DevOps, with minor modifications, and implements the most recent features. A user signs in using a Microsoft account to set up an environment, creating projects and adding team members. New features developed in short development cycles are added to the cloud version first. These features migrate to the on-premises version as updates, at approximately three-month intervals.
Architecture
Server architecture
Azure DevOps is built on multi-tier, scalable architecture. The primary structure consists of an application tier responsible for processing logic and maintaining the web application portal (referred to as Team Web Access or TWA). Azure DevOps is built using Windows Communication Foundation web services. These may be consumed by any client, although the client object model is recommended. The data tier and application tier can exist on the same machine.
To support scalability, the application tier can be load balanced and the data tier can be clustered. If us |
https://en.wikipedia.org/wiki/Seesaw%20molecular%20geometry | Disphenoidal or seesaw (also known as sawhorse) is a type of molecular geometry where there are four bonds to a central atom with overall C2v molecular symmetry. The name "seesaw" comes from the observation that it looks like a playground seesaw. Most commonly, four bonds to a central atom result in tetrahedral or, less commonly, square planar geometry.
The seesaw geometry occurs when a molecule has a steric number of 5, with the central atom being bonded to 4 other atoms and 1 lone pair (AX4E1 in AXE notation). An atom bonded to 5 other atoms (and no lone pairs) forms a trigonal bipyramid with two axial and three equatorial positions, but in the seesaw geometry one of the atoms is replaced by a lone pair of electrons, which is always in an equatorial position. This is true because the lone pair occupies more space near the central atom (A) than does a bonding pair of electrons. An equatorial lone pair is repelled by only two bonding pairs at 90°, whereas a hypothetical axial lone pair would be repelled by three bonding pairs at 90° which would make it stable. Repulsion by bonding pairs at 120° is much smaller and less important.
Structure
Compounds with disphenoidal (see-saw) geometry have two types of ligands: axial and equatorial. The axial pair lie along a common bond axis so that are related by a bond angle of 180°. The equatorial pair of ligands is situated in a plane orthogonal to the axis of the axial pair. Typically the bond distance to the axial ligands is longer than to the equatorial ligands. The ideal angle between the axial ligands and the equatorial ligands is 90°; whereas the ideal angle between the two equatorial ligands themselves is 120°.
Disphenoidal molecules, like trigonal bipyramidal ones, are subject to Berry pseudorotation in which the axial ligands move to equatorial positions and vice versa. This exchange of positions results in similar time-averaged environments for the two types of ligands. Thus, the 19F NMR spectrum of SF4 (like that |
https://en.wikipedia.org/wiki/Weyl%20expansion | In physics, the Weyl expansion, also known as the Weyl identity or angular spectrum expansion, expresses an outgoing spherical wave as a linear combination of plane waves. In a Cartesian coordinate system, it can be denoted as
,
where , and are the wavenumbers in their respective coordinate axes:
.
The expansion is named after Hermann Weyl, who published it in 1919. The Weyl identity is largely used to characterize the reflection and transmission of spherical waves at planar interfaces; it is often used to derive the Green's functions for Helmholtz equation in layered media. The expansion also covers evanescent wave components. It is often preferred to the Sommerfeld identity when the field representation is needed to be in Cartesian coordinates.
The resulting Weyl integral is commonly encountered in microwave integrated circuit analysis and electromagnetic radiation over a stratified medium; as in the case for Sommerfeld integral, it is numerically evaluated. As a result, it is used in calculation of Green's functions for method of moments for such geometries. Other uses include the descriptions of dipolar emissions near surfaces in nanophotonics, holographic inverse scattering problems, Green's functions in quantum electrodynamics and acoustic or seismic waves.
See also
Angular spectrum method
Fourier optics
Green's function
Plane wave expansion
Sommerfeld identity |
https://en.wikipedia.org/wiki/Keyboard%20buffer | A keyboard buffer is a section of computer memory used to hold keystrokes before they are processed.
Keyboard buffers have long been used in command-line processing. As a user enters a command, they see it echoed on their terminal and can edit it before it is processed by the computer.
In time-sharing systems, the location of the buffer depends on whether communications is full-duplex or half-duplex. In full-duplex systems, keystrokes are transmitted one by one. As the main computer receives each keystroke, it ordinarily appends the character which it represents to the end of the keyboard buffer. The exception is control characters, such as "delete" or "backspace" which correct typing mistakes by deleting the character at the end of the buffer.
In half-duplex systems, keystrokes are echoed locally on a computer terminal. The user can see the command line on his terminal and edit it before it is transmitted to the main computer. Thus the buffer is local.
On some early home computers, to minimize the necessary hardware, a CPU interrupt checked the keyboard's switches for key presses multiple times each second, and recorded the key presses in a keyboard buffer for the operating system or application software to read.
On some systems, if the user presses too many keys at once, the keyboard buffer overflows and will emit a beep from the computer's internal speaker.
Other uses
The use of keyboard buffers is sometimes known from the user experience side as typeahead. |
https://en.wikipedia.org/wiki/Media%20Go | Media Go is a media player and media library application that runs on Microsoft Windows and was developed by Sony Entertainment Network. The software organizes and plays a wide variety of multimedia content including video, music, podcasts and photos, and can share them in a network as a DLNA server. Media Go also manages content on various Sony mobile devices including the PlayStation Portable, PlayStation Vita, Walkman, Sony Tablet, and Xperia. Gracenote tagging is integrated, and in the past it also had a storefront from PlayStation Network and mora for purchasing media content.
Sony announced the discontinuation of the software by December 2017; it was replaced by Music Center for PC which only works with audio products like Walkman.
History
Media Go was introduced in 2009 by Sony Creative Software, alongside the Sony Ericsson W995, initially made for transferring media to Sony Ericsson handsets excluding in the Japanese market. It was expanded to the PSP following the release of PSP Go, replacing the PSP Media Manager. From 2013 it replaced the X-App in Japan as the media manager for Sony devices.
Features
Media Go has many features that can be used to manage and synchronise content. Advanced functionality allows music to be tagged with SensMe metadata, and support for track ratings and purchases that can be made from the PlayStation Store, Sony Xperia's PlayNow Arena or select partner stores (such as BigPond Music, for Telstra customers). Where applicable, Media Go will also automatically download and/or convert certain content (e.g. a podcast) into a suitable format. Media Go can also purchase, backup, and restore PlayStation Portable (PSP) and PlayStation Vita (PS Vita) games and other content, including digital comics; the ability to shop for and purchase PSP or PS Vita content from the PlayStation Store without a PSP or PS Vita connected to the host computer is now supported in current versions of Media Go. As of 2014, the PlayStation Store (except the |
https://en.wikipedia.org/wiki/Belisha%20beacon | A Belisha beacon () is an amber-coloured globe lamp atop a tall black and white striped pole, marking pedestrian crossings of roads in the United Kingdom, Ireland, and other countries historically influenced by Britain, such as Hong Kong, Malta, and Singapore. The beacons were named after Leslie Hore-Belisha (1893–1957), the Minister of Transport who, in 1934, added beacons to pedestrian crossings, marked by large metal studs in the road surface. These crossings were later painted in black and white stripes, and thus are known as zebra crossings. Legally, pedestrians have priority (over vehicles in the carriageway) on such crossings.
History
The first Belisha beacons were erected in the London authorities areas and, following the Road Traffic Act 1934, were rolled out nationally in 1935. In December 1941, a study was made into the cost effectiveness of melting down the 64,000 Belisha beacon posts to make munitions, a plan which threatened to "deprive the right hon. Member for Devonport (Mr. Hore-Belisha) of his last hope of immortality."
In 1948, the Central Office of Information produced a short film which showed the correct way to use a pedestrian crossing (without the stripes at this time).
Belisha beacons provide additional visibility to zebra crossings for motorists, primarily at night. The UK flash rate is 750 ms on, 750 ms off. Some crossings are set so that each beacon flashes alternately to the other side, but they often fall out of synchronization over time. Beacons with an outer ring of flashing amber LED lights, preferred for their brightness and low electricity consumption, are replacing traditional incandescent bulbs in many areas.
Some of the crossings have plastic poles that are translucent, and lit internally. This is immediately apparent in dull weather and at night. The clearly illuminated white sections announce the presence of the poles carrying the amber beacons, increasing the visibility of the crossings to all road users. These illuminat |
https://en.wikipedia.org/wiki/Kirigami | is a variation of origami, the Japanese art of folding paper. In , the paper is cut as well as being folded, resulting in a three-dimensional design that stands away from the page. typically does not use glue.
Overview
In the United States, the term was coined by Florence Temko from Japanese , , and , , in the title of her 1962 book, , the Creative Art of Paper cutting. The book achieved enough success that the word was accepted as the Western name for the art of paper cutting.
Typically, starts with a folded base, which is then unfolded; cuts are then opened and flattened to make the finished design. Simple are usually symmetrical, such as snowflakes, pentagrams, or orchid blossoms. A difference between and the art of "full base", or 180-degree opening structures, is that is made out of a single piece of paper that has then been cut.
Notable artists
(born 1924–), a renowned () artist known for his colourful , which have also been published as a book.
Nahoko Kojima (born 1981–), a professional contemporary Japanese artist, who pioneered sculptural, three-dimensional .
See also
History of origami
Origamic architecture
Paper cutting
Paper model |
https://en.wikipedia.org/wiki/Digestible%20Indispensable%20Amino%20Acid%20Score | Digestible Indispensable Amino Acid Score (DIAAS) is a protein quality method proposed in March 2013 by the Food and Agriculture Organization to replace the current protein ranking standard, the Protein Digestibility Corrected Amino Acid Score (PDCAAS).
The DIAAS accounts for amino acid digestibility at the end of the small intestine, providing a more accurate measure of the amounts of amino acids absorbed by the body and the protein's contribution to human amino acid and nitrogen requirements. This is in contrast to the PDCAAS, which is based on an estimate of digestibility over the total digestive tract. Values stated using this method generally overestimate the amount of amino acids absorbed.
Reference pattern
Amino acid requirements were determined in two parts. The amino acid distribution of breast milk was used for the 0 to 6 month age range, and existing amino acid data was used for older ages after adjustment for digestibility. The reference amino acid requirements are presented below.
Example values
The table shows the ratings of selected foods comparing PDCAAS to DIAAS. The quality of various sources of protein depends on how it is processed, refined, stored, or cooked. (preparation is unspecified for some values in the table, but does not necessarily differ in preparation from the foods where preparation is specified). A major difference between DIAAS and PDCAAS, is that PDCAAS is truncated at 100%, while DIAAS is not. Multiple protein sources can also be combined to increase DIAAS, which can be effective at raising the max DIAAS of plant-based diets.
See also
Amino acid score
Protein Digestibility Corrected Amino Acid Score
Protein quality
Net protein utilization
Nitrogen balance |
https://en.wikipedia.org/wiki/Sodium%20stibogluconate | Sodium stibogluconate, sold under the brand name Pentostam among others, is a medication used to treat leishmaniasis. This includes leishmaniasis of the cutaneous, visceral, and mucosal types. Some combination of miltefosine, paramycin and liposomal amphotericin B, however, may be recommended due to issues with resistance. It is given by injection.
Side effects are common and include loss of appetite, nausea, muscle pains, headache, and feeling tired. Serious side effect may include an irregular heartbeat or pancreatitis. Sodium stibogluconate is less safe than some other options during pregnancy. It is not believed to result in any problems if used during breastfeeding. Sodium stibogluconate is in the pentavalent antimonials class of medication.
Sodium stibogluconate has been studied as early as 1937 and has been in medical use since the 1940s. It is on the World Health Organization's List of Essential Medicines. In the United States, it is available from the Centers for Disease Control.
Side effects
Sodium stibogluconate is exceedingly toxic to veins. One of the practical problems is that after a few doses it can become exceedingly difficult to find a vein in which to inject the drug. The insertion of a peripherally inserted central catheter (PICC) does not prevent the problem and can instead exacerbate it: the entire vein along the course of the PICC line can become inflamed and thrombose. Large doses of sodium stibogluconate are often administered as dilute solutions.
Pancreatitis is a common deleterious effect of the drug, and the serum amylase or lipase should be monitored twice weekly; there is no need to stop treatment if the amylase remains less than four times the upper limit of normal; if the amylase rises above the cut-off, then treatment should be interrupted until the amylase falls to less than twice the upper limit of normal, whereupon treatment can be resumed. Cardiac conduction disturbances are less common, but electrocardiograph (ECG) monito |
https://en.wikipedia.org/wiki/EPS%20Europhysics%20Prize | The EPS CMD Europhysics Prize is awarded (currently every 2nd year) since 1975 by the Condensed Matter Division of the European Physical Society, in recognition of recent work (completed in the 5 years preceding the attribution of the award) by one or more individuals, for scientific excellence in the area of condensed matter physics. It is one of Europe’s most prestigious prizes in the field of condensed matter physics. Several laureates of the EPS CMD Europhysics Prize also received a Nobel Prize in Physics or Chemistry (Geim, Novoselov, Fert, Grünberg, Kroto, Smalley, Ertl, Bednorz, Müller, Binnig, Rohrer, von Klitzing, Alferov).
Laureates
Source: European Physical Society
2022: Prof. Agnès Barthélémy, Manuel Bibes, Ramamoorthy Ramesh and Nicola Spaldin for seminal contributions to the physics and applications of multiferroic and magnetoelectric materials.
2020: Jörg Wrachtrup - Pioneering studies on quantum coherence in solid-state systems and their applications for sensing, and, in particular, for major breakthroughs in the study of the optical and spin properties of nitrogen vacancy centers in diamond.
2018: Lucio Braicovich and Giacomo Claudio Ghiringhelli - The development and scientific exploration of high-resolution Resonant Inelastic X-ray Scattering (RIXS).
2016: , Alexei N. Bogdanov, Christian Pfleiderer, , Ashvin Vishwanath - Theoretical prediction, experimental discovery and theoretical analysis of a magnetic skyrmion phase in MnSi, a new state of matter.
2014: Harold Y. Hwang, Jochen Mannhart and - for the discovery and investigation of electron liquids at oxide interfaces
2012: Steven T. Bramwell, Claudio Castelnovo, Santiago Grigera, Roderich Moessner, Shivaji Sondhi and Alan Tennant - Prediction and experimental observation of magnetic monopoles in spin ice
2010: Hartmut Buhmann, Charles Kane, Eugene J. Mele, Laurens W. Molenkamp and Shoucheng Zhang - Theoretical prediction and the experimental observation of the quantum spin Hall ef |
https://en.wikipedia.org/wiki/Pohlsepia | Pohlsepia mazonensis is a species of fossil organism with unknown affinity. Although it was originally identified as an extinct cephalopod, later studies denied that interpretation. The species is known from a single exceptionally preserved fossil discovered in the late Carboniferous (Pennsylvanian) Francis Creek Shale (Mazon Creek fossil beds) of the Carbondale Formation, north-east Illinois, United States.
Pohlsepia mazonensis is named after its discoverer, James Pohl, and the type locality, Mazon Creek. Its habitat was the shallows seawards of a major river delta in what at that time was an inland ocean between the Midwest and the Appalachians. In its initial description, it was considered to be the oldest known octopus, but later studies have considered this classification dubious. In 2022, it was even shown that it may not be a mollusk.
The type specimen is reposited at the Field Museum of Natural History in Chicago, Illinois.
Fossil
The Pohlsepia mazonensis fossil found by James Pohl is the only known example of the species. Most notably, the fossil has ten arms. The extra two arms are shorter, while the other eight are similar in length.
The wide fossil is “sack-shaped” with indistinct features including a poorly defined head. While it is unclear, one of these features could be an ink sac. The fossil lacks arm hooks and suckers and all of these factors combine to make the assigning of the order Cirroctopoda controversial.
Etymology
Genus name Pohlsepia is came from its discoverer James Pohl. He is the son of Joe Pohl and together they have collected fossils in the Mazon Creek area. Originally from Wisconsin and Minnesota, Pohl is a native Midwesterner. He and his father have donated their fossils to museums in the area, including Pohlsepia mazonensis to the Field Museum.
Classification
In 2000, Joanne Kluessendorf assigned Pohlsepia mazonensis to the order Cirroctopoda. Many other researchers disagreed, citing the lack of internal structure. The poss |
https://en.wikipedia.org/wiki/First%20International%20Topological%20Conference | The First International Topological Conference was held in Moscow, 4–10 September, 1935. With presentations by topologists from 10 different countries it constituted the first genuinely international meeting devoted to topology in the world history of the mathematical community. Although a previous mathematical conference had been held in Kharkiv, and attended by Jacques Hadamard, this turned out to be the only truly international conference organised under the Stalin regime. Pavel Aleksandrov played a key role in organising the conference. The foreign delegates were accommodated in major hotels across Moscow, although according to André Weil, the principal form of sustenance was Caviar Canapes served in the conference hall, as no food was available in the hotel restaurants.
Presentations
Documentation of the conference varies, but this summary was drawn from various sources.
Homology Theory
Karol Borsuk: ‘‘On spheroidal spaces’’
Eduard Čech: "Accessibility and Homology'"
Israel Isaakovich Gordon: ‘‘On the intersection invariants of a complex and its residual space.’
Solomon Lefschetz: ‘‘On locally connected sets.’’
Attendees
The following topologists made presentations:
Czechoslovakia:
Eduard Čech
France:
André Weil
Netherlands
Hans Freudenthal
Egbert van Kampen
Poland:
Karol Borsuk
Kazimierz Kuratowski
Juliusz Schauder
Kazimierz Zarankiewicz
USA:
James Waddell Alexander II
Garrett Birkhoff
Solomon Lefschetz
John von Neumann
Albert W. Tucker
Hassler Whitney
USSR:
Pavel Aleksandrov
Felix Frankl
Israel Isaakovich Gordon
Maria A. Nikolaenko
Julia Rozanska
Lev Pontryagin
Vyacheslav Stepanov
Lev Tumarkin |
https://en.wikipedia.org/wiki/Richard%20Goldschmidt | Richard Benedict Goldschmidt (April 12, 1878 – April 24, 1958) was a German geneticist. He is considered the first to attempt to integrate genetics, development, and evolution. He pioneered understanding of reaction norms, genetic assimilation, dynamical genetics, sex determination, and heterochrony. Controversially, Goldschmidt advanced a model of macroevolution through macromutations popularly known as the "Hopeful Monster" hypothesis.
Goldschmidt also described the nervous system of the nematode, a piece of work that influenced Sydney Brenner to study the "wiring diagram" of Caenorhabditis elegans, winning Brenner and his colleagues the Nobel Prize in 2002.
Childhood and education
Goldschmidt was born in Frankfurt-am-Main, Germany to upper-middle class parents of Ashkenazi Jewish heritage. He had a classical education and entered the University of Heidelberg in 1896, where he became interested in natural history. From 1899 Goldschmidt studied anatomy and zoology at the University of Heidelberg with Otto Bütschli and Carl Gegenbaur. He received his Ph.D. under Bütschli in 1902, studying development of the trematode Polystomum.
Career
In 1903 Goldschmidt began working as an assistant to Richard Hertwig at the University of Munich, where he continued his work on nematodes and their histology, including studies of the nervous system development of Ascaris and the anatomy of Amphioxus. He founded the histology journal Archiv für Zellforschung while working in Hertwig's laboratory. Under Hertwig's influence, he also began to take an interest in chromosome behavior and the new field of genetics.
In 1909 Goldschmidt became professor at the University of Munich and, inspired by Wilhelm Johannsen's genetics treatise Elemente der exakten Erblichkeitslehre, began to study sex determination and other aspects of the genetics of Lymantria dispar, the gypsy moth, of which he was crossbreeding different races. He observed various stages of their sexual development, and |
https://en.wikipedia.org/wiki/Zeta%20function%20%28operator%29 | The zeta function of a mathematical operator is a function defined as
for those values of s where this expression exists, and as an analytic continuation of this function for other values of s. Here "tr" denotes a functional trace.
The zeta function may also be expressible as a spectral zeta function in terms of the eigenvalues of the operator by
.
It is used in giving a rigorous definition to the functional determinant of an operator, which is given by
The Minakshisundaram–Pleijel zeta function is an example, when the operator is the Laplacian of a compact Riemannian manifold.
One of the most important motivations for Arakelov theory is the zeta functions for operators with the method of heat kernels generalized algebro-geometrically.
See also
Quillen metric |
https://en.wikipedia.org/wiki/Laser%20line%20level | A laser line level is a tool combining a spirit level and/or plumb bob with a laser to display an accurately horizontal or vertical illuminated line on a surface the laser line level is laid against.
Laser line levels are used wherever accurate verticals and horizontals are required, typically in the construction and cabinetry industries. Some models are inexpensive enough for do-it-yourself applications.
The laser beam is fanned to produce a thin plane beam accurately horizontal or vertical, rather than a pinpoint beam. The axis of the laser is offset from the wall, so that a pinpoint beam would be parallel to and offset from the wall, and would not illuminate it; the fanned beam will intersect the wall, creating an accurately horizontal (or vertical) illuminated line along it.
The machine is set up using the built-in spirit level or plumb bob, and the line along the surface is then guaranteed to be accurately horizontal or vertical to within a certain tolerance, specified either in millimetres per metre or fractions of an inch over a specified distance in feet. A more advanced device may be accurate to within 0.3 mm/m; while lower-end models may be closer to 1.5 mm/m.
The illuminated line is necessarily absolutely straight, so that the line level can be used as a straightedge; for example, to see if a shelf is warped, even if not horizontal.
See also
Dumpy level
Theodolite
List of laser articles
Laser Machine Control |
https://en.wikipedia.org/wiki/Cramer%E2%80%93Castillon%20problem | In geometry, the Cramer–Castillon problem is a problem stated by the Swiss mathematician Gabriel Cramer solved by the Italian mathematician, resident in Berlin, Jean de Castillon in 1776.
The problem consists of (see the image):
Given a circle and three points in the same plane and not on , to construct every possible triangle inscribed in whose sides (or their elongations) pass through respectively.
Centuries before, Pappus of Alexandria had solved a special case: when the three points are collinear. But the general case had the reputation of being very difficult.
After the geometrical construction of Castillon, Lagrange found an analytic solution, easier than Castillon's. In the beginning of the 19th century, Lazare Carnot generalized it to points. |
https://en.wikipedia.org/wiki/Hypergiant | A hypergiant (luminosity class 0 or Ia+) is a very rare type of star that has an extremely high luminosity, mass, size and mass loss because of its extreme stellar winds. The term hypergiant is defined as luminosity class 0 (zero) in the MKK system. However, this is rarely seen in literature or in published spectral classifications, except for specific well-defined groups such as the yellow hypergiants, RSG (red supergiants), or blue B(e) supergiants with emission spectra. More commonly, hypergiants are classed as Ia-0 or Ia+, but red supergiants are rarely assigned these spectral classifications. Astronomers are interested in these stars because they relate to understanding stellar evolution, especially star formation, stability, and their expected demise as supernovae.
Origin and definition
In 1956, the astronomers Feast and Thackeray used the term super-supergiant (later changed into hypergiant) for stars with an absolute magnitude brighter than MV = −7 (MBol will be larger for very cool and very hot stars, for example at least −9.7 for a B0 hypergiant). In 1971, Keenan suggested that the term would be used only for supergiants showing at least one broad emission component in Hα, indicating an extended stellar atmosphere or a relatively large mass loss rate. The Keenan criterion is the one most commonly used by scientists today.
To be classified as a hypergiant, a star must be highly luminous and have spectral signatures showing atmospheric instability and high mass loss. Hence it is possible for a non-hypergiant, supergiant star to have the same or higher luminosity as a hypergiant of the same spectral class. Hypergiants are expected to have a characteristic broadening and red-shifting of their spectral lines, producing a distinctive spectral shape known as a P Cygni profile. The use of hydrogen emission lines is not helpful for defining the coolest hypergiants, and these are largely classified by luminosity since mass loss is almost inevitable for the class.
|
https://en.wikipedia.org/wiki/Group-contribution%20method | A group-contribution method in chemistry is a technique to estimate and predict thermodynamic and other properties from molecular structures.
Introduction
In today's chemical processes hundreds of thousands of components are used. The Chemical Abstracts Service registry lists 56 million substances, but many of these are only of scientific interest.
Process designers need to know some basic chemical properties of the components and their mixtures. Experimental measurement is often too expensive.
Predictive methods can replace measurements if they provide sufficiently good estimations. The estimated properties cannot be as precise as well-made measurements, but for many purposes the quality of estimated properties is sufficient. Predictive methods can also be used to check the results of experimental work.
Principles
A group-contribution method uses the principle that some simple aspects of the structures of chemical components are always the same in many different molecules. The smallest common constituents are the atoms and the bonds. The vast majority of organic components, for example, are built of carbon, hydrogen, oxygen, nitrogen, halogens, and maybe sulfur or phosphorus. Together with a single, a double, and a triple bond there are only ten atom types (not including astatine) and three bond types to build thousands of components. The next slightly more complex building blocks of components are functional groups, which are themselves built from few atoms and bonds.
A group-contribution method is used to predict properties of pure components and mixtures by using group or atom properties. This reduces the number of needed data dramatically. Instead of needing to know the properties of thousands or millions of compounds, only data for a few dozens or hundreds of groups have to be known.
Additive group-contribution method
The simplest form of a group-contribution method is the determination of a component property by summing up the group contribution:
|
https://en.wikipedia.org/wiki/1%2C1%2C6-Trimethyl-1%2C2-dihydronaphthalene | 1,1,6-Trimethyl-1,2-dihydronaphthalene (TDN) is an aroma compound present in wine, particularly aged Rieslings. Chemically, it is classified as a 13C-norisoprenoid, as it has thirteen carbon atoms, and is derived from an isoprenoid by the loss of methylene groups.
In wines, TDN is generally considered to contribute to a desirable aroma in low concentrations, but an undesirable aroma in higher concentrations. The aroma is commonly described as a petrol note or by the French term goût de pétrole.
TDN is believed to be a degradation product of β-carotene and lutein. TDN can also by synthesized in the laboratory from either of the ionones, α-ionone or β-ionone. |
https://en.wikipedia.org/wiki/Green%20strength | Green strength, or handling strength, can be defined as the strength of a material as it is processed to form its final ultimate tensile strength. This strength is usually considerably lower than the final ultimate strength of a material. The term green strength is usually referenced when discussing non-metallic materials such as adhesives and elastomers (such as rubber). Recently, it has also been referenced in metallurgy applications such as powdered metallurgy.
Adhesives
A joint made through the use of an adhesive can be referred to as an adhesive joint or bond.
The green strength of adhesives is the early development of bond strength of an adhesive. It indicated "that the adhesive bond is strong enough to be handled a short time after the adherents are mated but much before full cure is obtained." Usually, this strength is significantly lower than the final curing strength. Most adhesives typically have an initial green strength and a final ultimate tensile strength listed for their application. For household adhesives, this data is usually reflected on the packaging.
The best example of this is seen in typical epoxies from a local hardware stores. During curing, the epoxy will travel into an initial curing phase, also called "green phase", when it begins to gel. At that point, the epoxy is no longer workable and will move from being tacky to a firm rubber-like texture. While the epoxy is only partially cured at this point, it has formed a lower green strength. Normally, this process occurs within 30 minutes to 1 hour. At this time, the part in question can be handled, but cannot handle large loads or stress. It typically takes up to 24 hours for a standard epoxy to cure to its final and complete strength.
Temperature is an important factor in the time it takes for an adhesive to form the green strength. While this can vary from adhesive to adhesive, general speaking, heat can speed up the process to form the green strength and the overall curing time. Time |
https://en.wikipedia.org/wiki/Bionic%20Leaf | The Bionic Leaf is a biomimetic system that gathers solar energy via photovoltaic cells that can be stored or used in a number of different functions. Bionic leaves can be composed of both synthetic (metals, ceramics, polymers, etc.) and organic materials (bacteria), or solely made of synthetic materials. The Bionic Leaf has the potential to be implemented in communities, such as urbanized areas to provide clean air as well as providing needed clean energy.
History
In 2009 at MIT, Daniel Nocera's lab first developed the "artificial leaf", a device made from silicon and an anode electrocatalyst for the oxidation of water, capable of splitting water into hydrogen and oxygen gases. In 2012, Nocera came to Harvard and The Silver Lab of Harvard Medical School joined Nocera’s team. Together the teams expanded the existing technology to create the Bionic Leaf. It merged the concept of the artificial leaf with genetically engineered bacteria that feed on the hydrogen and convert CO2 in the air into alcohol fuels or chemicals.
The first version of the teams Bionic Leaf was created in 2015 but the catalyst used was harmful to the bacteria. In 2016, a new catalyst was designed to solve this issue, named the "Bionic Leaf 2.0". Other versions of artificial leaves have been developed by the California Institute of Technology and the Joint Center for Artificial Photosynthesis, the University of Waterloo, and the University of Cambridge.
Mechanics
Photosynthesis
In natural photosynthesis, photosynthetic organisms produce energy-rich organic molecules from water and carbon dioxide by using solar radiation. Therefore, the process of photosynthesis removes carbon dioxide, a greenhouse gas, from the air. Artificial photosynthesis, as performed by the Bionic Leaf, is approximately 10 times more efficient than natural photosynthesis. Using a catalyst, the Bionic Leaf can remove excess carbon dioxide in the air and convert that to useful alcohol fuels, like isopropanol and isobutan |
https://en.wikipedia.org/wiki/Vasoconstriction | Vasoconstriction is the narrowing of the blood vessels resulting from contraction of the muscular wall of the vessels, in particular the large arteries and small arterioles. The process is the opposite of vasodilation, the widening of blood vessels. The process is particularly important in controlling hemorrhage and reducing acute blood loss. When blood vessels constrict, the flow of blood is restricted or decreased, thus retaining body heat or increasing vascular resistance. This makes the skin turn paler because less blood reaches the surface, reducing the radiation of heat. On a larger level, vasoconstriction is one mechanism by which the body regulates and maintains mean arterial pressure.
Medications causing vasoconstriction, also known as vasoconstrictors, are one type of medicine used to raise blood pressure. Generalized vasoconstriction usually results in an increase in systemic blood pressure, but it may also occur in specific tissues, causing a localized reduction in blood flow. The extent of vasoconstriction may be slight or severe depending on the substance or circumstance. Many vasoconstrictors also cause pupil dilation. Medications that cause vasoconstriction include: antihistamines, decongestants, and stimulants. Severe vasoconstriction may result in symptoms of intermittent claudication.
General mechanism
The mechanism that leads to vasoconstriction results from the increased concentration of calcium (Ca2+ ions) within vascular smooth muscle cells. However, the specific mechanisms for generating an increased intracellular concentration of calcium depends on the vasoconstrictor. Smooth muscle cells are capable of generating action potentials, but this mechanism is rarely utilized for contraction in the vasculature. Hormonal or pharmacokinetic components are more physiologically relevant. Two common stimuli for eliciting smooth muscle contraction are circulating epinephrine and activation of the sympathetic nervous system (through release of norepin |
https://en.wikipedia.org/wiki/George%20Leitmann | George Leitmann (born May 24, 1925) is an Austrian-born American engineering scientist and educator.
Early life and education
Leitmann was born on May 24, 1925, to a fully assimilated Jewish family in Vienna, Austria. His paternal grandfather was a career officer with the rank of lieutenant colonel in the Imperial Army. His father had been a volunteer in the Austrian Army in World War I and was wounded twice on the Serbian front.
Nonetheless, by the spring of 1940 the situation in Austria had become so dangerous that George's father fled to neighboring Yugoslavia, still an independent kingdom, and the rest of the family, George, his mother and two grandmothers, were able to emigrate to the US in April 1940. Tragically, Yugoslavia was occupied by Germany a year later and George's father was murdered in a concentration camp in Nis, Serbia.
George attended a Technical High School in New York from which he graduated in December 1943, whereupon he immediately volunteered for the Army and was inducted in February 1944 into a Combat Engineer Battalion, which began its combat duties in France and Germany in late 1944. During the battle of the Colmar Pocket, George's unit was attached to the French First Army which liberated Colmar. For George's performance in this action as a member of the reconnaissance unit, he was awarded the Croix de Guerre avec Palme.
After the end of the war in Europe, George was transferred to the Army Counter Intelligence Corps as its youngest Special Agent and, among other assignments, served as an interrogator at the Nuremberg War Crimes Trial. In 1955, he married Nancy Lloyd. They have two children, son Josef, and daughter Elaine, as well as three grandchildren and two great-grandchildren.
Academic career
After the discharge from the army in May 1946, George studied physics at Columbia University and received the BA and MS degrees in 1949 and 1950, respectively. From 1950 to 1957 he was employed at the US Naval Ordnance Station (USNOTS), Chi |
https://en.wikipedia.org/wiki/Phineas%20Gage | Phineas P. Gage (18231860) was an American railroad construction foreman remembered for his improbable survival of an accident in which a large iron rod was driven completely through his head, destroying much of his brain's left frontal lobe, and for that injury's reported effects on his personality and behavior over the remaining 12 years of his lifeeffects sufficiently profound that friends saw him (for a time at least) as "no longer Gage".
Long known as the "American Crowbar Case"once termed "the case which more than all others is to excite our wonder, impair the value of prognosis, and even to subvert our doctrines"Phineas Gage influenced 19th-century discussion about the mind and brain, debate on cerebral , and was perhaps the first case to suggest the brain's role in , and that damage to specific parts of the brain might induce specific mental changes.
Gage is a fixture in the curricula of neurology, psychology, and neuroscience, one of "the great medical curiosities of all time" and "a living part of the medical folklore" frequently mentioned in books and scientific papers; he even has a minor place in popular culture. Despite this celebrity, the body of established fact about Gage and what he was like (whether before or after his injury) is small, which has allowed "the fitting of almost any theory [desired] to the small number of facts we have"Gage acting as a "Rorschach inkblot" in which proponents of various conflicting theories of the brain all saw support for their views. Historically, published accounts of Gage (including scientific ones) have almost always severely exaggerated and distorted his behavioral changes, frequently contradicting the known facts.
A report of Gage's physical and mental condition shortly before his death implies that his most serious mental changes were temporary, so that in later life he was far more functional, and socially far better adapted, than in the years immediately following his accident. A social recovery hypot |
https://en.wikipedia.org/wiki/Wagner%27s%20theorem | In graph theory, Wagner's theorem is a mathematical forbidden graph characterization of planar graphs, named after Klaus Wagner, stating that a finite graph is planar if and only if its minors include neither K5 (the complete graph on five vertices) nor K3,3 (the utility graph, a complete bipartite graph on six vertices). This was one of the earliest results in the theory of graph minors and can be seen as a forerunner of the Robertson–Seymour theorem.
Definitions and statement
A planar embedding of a given graph is a drawing of the graph in the Euclidean plane, with points for its vertices and curves for its edges, in such a way that the only intersections between pairs of edges are at a common endpoint of the two edges. A minor of a given graph is another graph formed by deleting vertices, deleting edges, and contracting edges. When an edge is contracted, its two endpoints are merged to form a single vertex. In some versions of graph minor theory the graph resulting from a contraction is simplified by removing self-loops and multiple adjacencies, while in other version multigraphs are allowed, but this variation makes no difference to Wagner's theorem.
Wagner's theorem states that every graph has either a planar embedding, or a minor of one of two types, the complete graph K5 or the complete bipartite graph K3,3. (It is also possible for a single graph to have both types of minor.)
If a given graph is planar, so are all its minors: vertex and edge deletion obviously preserve planarity, and edge contraction can also be done in a planarity-preserving way, by leaving one of the two endpoints of the contracted edge in place and routing all of the edges that were incident to the other endpoint along the path of the contracted edge.
A minor-minimal non-planar graph is a graph that is not planar, but in which all proper minors (minors formed by at least one deletion or contraction) are planar. Another way of stating Wagner's theorem is that there are only two minor-mi |
https://en.wikipedia.org/wiki/Egyptian%20fraction | An Egyptian fraction is a finite sum of distinct unit fractions, such as
That is, each fraction in the expression has a numerator equal to 1 and a denominator that is a positive integer, and all the denominators differ from each other. The value of an expression of this type is a positive rational number ; for instance the Egyptian fraction above sums to . Every positive rational number can be represented by an Egyptian fraction. Sums of this type, and similar sums also including and as summands, were used as a serious notation for rational numbers by the ancient Egyptians, and continued to be used by other civilizations into medieval times. In modern mathematical notation, Egyptian fractions have been superseded by vulgar fractions and decimal notation. However, Egyptian fractions continue to be an object of study in modern number theory and recreational mathematics, as well as in modern historical studies of ancient mathematics.
Applications
Beyond their historical use, Egyptian fractions have some practical advantages over other representations of fractional numbers.
For instance, Egyptian fractions can help in dividing food or other objects into equal shares. For example, if one wants to divide 5 pizzas equally among 8 diners, the Egyptian fraction
means that each diner gets half a pizza plus another eighth of a pizza, for example by splitting 4 pizzas into 8 halves, and the remaining pizza into 8 eighths. Exercises in performing this sort of fair division of food are a standard classroom example in teaching students to work with unit fractions.
Egyptian fractions can provide a solution to rope-burning puzzles, in which a given duration is to be measured by igniting non-uniform ropes which burn out after a unit time. Any rational fraction of a unit of time can be measured by expanding the fraction into a sum of unit fractions and then, for each unit fraction , burning a rope so that it always has simultaneously lit points where it is burning. For this ap |
https://en.wikipedia.org/wiki/Particle%20aggregation | Particle agglomeration refers to the formation of assemblages in a suspension and represents a mechanism leading to the functional destabilization of colloidal systems. During this process, particles dispersed in the liquid phase stick to each other, and spontaneously form irregular particle assemblages, flocs, or agglomerates. This phenomenon is also referred to as coagulation or flocculation and such a suspension is also called unstable. Particle agglomeration can be induced by adding salts or other chemicals referred to as coagulant or flocculant.
Particle agglomeration can be a reversible or irreversible process. Particle agglomerates defined as "hard agglomerates" are more difficult to redisperse to the initial single particles. In the course of agglomeration, the agglomerates will grow in size, and as a consequence they may settle to the bottom of the container, which is referred to as sedimentation. Alternatively, a colloidal gel may form in concentrated suspensions which changes its rheological properties. The reverse process whereby particle agglomerates are re-dispersed as individual particles, referred to as peptization, hardly occurs spontaneously, but may occur under stirring or shear.
Colloidal particles may also remain dispersed in liquids for long periods of time (days to years). This phenomenon is referred to as colloidal stability and such a suspension is said to be functionally stable. Stable suspensions are often obtained at low salt concentrations or by addition of chemicals referred to as stabilizers or stabilizing agents. The stability of particles, colloidal or otherwise, is most commonly evaluated in terms of zeta potential. This parameter provides a readily quantifiable measure of interparticle repulsion, which is the key inhibitor of particle aggregation.
Similar agglomeration processes occur in other dispersed systems too. In emulsions, they may also be coupled to droplet coalescence, and not only lead to sedimentation but also to crea |
https://en.wikipedia.org/wiki/Lindbladian | In quantum mechanics, the Gorini–Kossakowski–Sudarshan–Lindblad equation (GKSL equation, named after Vittorio Gorini, Andrzej Kossakowski, George Sudarshan and Göran Lindblad), master equation in Lindblad form, quantum Liouvillian, or Lindbladian is one of the general forms of Markovian master equations describing open quantum systems. It generalizes the Schrödinger equation to open quantum systems; that is, systems in contacts with their surroundings. The resulting dynamics is no longer unitary, but still satisfies the property of being trace-preserving and completely positive for any initial condition.
The Schrödinger equation or, actually, the von Neumann equation, is a special case of the GKSL equation, which has led to some speculation that quantum mechanics may be productively extended and expanded through further application and analysis of the Lindblad equation. The Schrödinger equation deals with state vectors, which can only describe pure quantum states and are thus less general than density matrices, which can describe mixed states as well.
Motivation
In the canonical formulation of quantum mechanics, a system's time evolution is governed by unitary dynamics. This implies that there is no decay and phase coherence is maintained throughout the process, and is a consequence of the fact that all participating degrees of freedom are considered. However, any real physical system is not absolutely isolated, and will interact with its environment. This interaction with degrees of freedom external to the system results in dissipation of energy into the surroundings, causing decay and randomization of phase. More so, understanding the interaction of a quantum system with its environment is necessary for understanding many commonly observed phenomena like the spontaneous emission of light from excited atoms, or the performance of many quantum technological devices, like the laser.
Certain mathematical techniques have been introduced to treat the interaction |
https://en.wikipedia.org/wiki/Costodiaphragmatic%20recess | The costodiaphragmatic recess, also called the costophrenic recess or phrenicocostal sinus, is the posterolateral fringe of the pleural space, a potential space around the lung inside the pleural cavity. It is located at the acutely angled junction ("reflection") between the costal and diaphragmatic parietal pleurae, and is interpreted two-dimensionally on plain X-rays as the costophrenic angle. It measures approximately vertically and extends from the eighth to the tenth rib along the mid-axillary line.
Function
The lungs expand into this recess during forced inspiration; however, the recess never gets filled completely. During expiration, it contains nothing apart from gravitated serous fluid.
Clinical significance
Pleural effusions collect in the costodiaphragmatic recess when in standing position, and present on plain X-rays as "blunting" of the costophrenic angle.
A thoracocentesis (pleural tap) is often performed here while a patient is in full expiration because of less risk of puncturing the lungs and thereby causing pneumothorax.
Imaging
In anatomy, the costophrenic angles are the places where the diaphragm (-phrenic) meets the ribs (costo-).
Each costophrenic angle can normally be seen as on chest x-ray as a sharply-pointed, downward indentation (dark) between each hemi-diaphragm (white) and the adjacent chest wall (white). A small portion of each lung normally reaches into the costophrenic angle. The normal angle usually measures thirty degrees.
Pleural effusion
With pleural effusion, fluid often builds up in the costophrenic angle (due to gravity). This can push the lung upwards, resulting in "blunting" of the costophrenic angle.
The posterior angle is the deepest.
Obtuse angulation is sign of disease.
Chest x-ray is the first test done to confirm the presence of pleural fluid. The lateral upright chest x-ray should be examined when a pleural effusion is suspected. In an upright x-ray, 75 mL of fluid blunts the posterior costophrenic angle. B |
https://en.wikipedia.org/wiki/Debreu%27s%20representation%20theorems | In economics, the Debreu's theorems are preference representation theorems -- statements about the representation of a preference ordering by a real-valued utility function. The theorems were proved by Gerard Debreu during the 1950s.
Background
Suppose a person is asked questions of the form "Do you prefer A or B?" (when A and B can be options, actions to take, states of the world, consumption bundles, etc.). All the responses are recorded and form the person's preference relation. Instead of recording the person's preferences between every pair of options, it would be much more convenient to have a single utility function - a function that maps a real number to each option, such that the utility of option A is larger than that of option B if and only if the agent prefers A to B.
Debreu's theorems address the following question: what conditions on the preference relation guarantee the existence of a representing utility function?
Existence of ordinal utility function
The 1954 Theorems say, roughly, that every preference relation which is complete, transitive and continuous, can be represented by a continuous ordinal utility function.
Statement
The theorems are usually applied to spaces of finite commodities. However, they are applicable in a much more general setting. These are the general assumptions:
X is a topological space.
is a relation on X which is total (all items are comparable) and transitive.
is continuous. This means that the following equivalent conditions are satisfied:
For every , the sets and are topologically closed in .
For every sequence such that , if for all i then , and if for all i then
Each one of the following conditions guarantees the existence of a real-valued continuous function that represents the preference relation . The conditions are increasingly general, so for example, condition 1 implies 2, which implies 3, which implies 4.
1. The set of equivalence classes of the relation (defined by: iff and ) are a cou |
https://en.wikipedia.org/wiki/Synchronization%20%28computer%20science%29 | In computer science, synchronization is the task of coordinating multiple of processes to join up or handshake at a certain point, in order to reach an agreement or commit to a certain sequence of action.
Motivation
The need for synchronization does not arise merely in multi-processor systems but for any kind of concurrent processes; even in single processor systems. Mentioned below are some of the main needs for synchronization:
Forks and Joins: When a job arrives at a fork point, it is split into N sub-jobs which are then serviced by n tasks. After being serviced, each sub-job waits until all other sub-jobs are done processing. Then, they are joined again and leave the system. Thus, parallel programming requires synchronization as all the parallel processes wait for several other processes to occur.
Producer-Consumer: In a producer-consumer relationship, the consumer process is dependent on the producer process until the necessary data has been produced.
Exclusive use resources: When multiple processes are dependent on a resource and they need to access it at the same time, the operating system needs to ensure that only one processor accesses it at a given point in time. This reduces concurrency.
Requirements
Thread synchronization is defined as a mechanism which ensures that two or more concurrent processes or threads do not simultaneously execute some particular program segment known as critical section. Processes' access to critical section is controlled by using synchronization techniques. When one thread starts executing the critical section (serialized segment of the program) the other thread should wait until the first thread finishes. If proper synchronization techniques are not applied, it may cause a race condition where the values of variables may be unpredictable and vary depending on the timings of context switches of the processes or threads.
For example, suppose that there are three processes, namely 1, 2, and 3. All three of them are concu |
https://en.wikipedia.org/wiki/Glycerol%202-phosphate | Glycerol 2-phosphate is the conjugate base of phosphoric ester of glycerol. It is commonly known as β-glycerophosphate or BGP. Unlike glycerol 1-phosphate and glycerol 3-phosphate, this isomer is not chiral. It is also less common.
Applications
β-Glycerophosphate is an inhibitor of the enzyme serine-threonine phosphatase. It is often used in combination with other phosphatase/protease inhibitors for broad spectrum inhibition.
β-Glycerophosphate is also used to drive osteogenic differentiation of bone marrow stem cells in vitro.
β-Glycerophosphate is used to buffer M17 media for Lactococcus culture in recombinant protein expression.
Notes
Organophosphates |
https://en.wikipedia.org/wiki/National%20Air%20Pollution%20Monitoring%20Network | The National Air Pollution Monitoring Network (NABEL) is a joint project of the Swiss Federal Office for the Environment (BAFU) and the Swiss Federal Laboratories for Materials Science and Technology (EMPA), based in Dübendorf, in the canton of Zurich.
Establishment of the National Monitoring Network
As part of an international collaboration of 11 countries, EMPA has been continuously measuring air pollutants since 1968, initially with four stations. From 1972 to 1977, the measurements were continued in the OECD Base Program, and the project was expanded to eight stations in 1978. The international measurements of the European Monitoring and Evaluation Programme (EMEP) were integrated following the signing of the United Nations Economic Commission for Europe (UN/ECE) Convention on Long Range Transboundary Air Pollution the following year. Within the framework of the research program "Forest Damage and Air Pollution in Switzerland" (NFP14), measurements were taken at three forest sites. The measurement network was expanded to its current level of 16 stations in 1990/91.
Activities and Monitoring Stations
NABEL monitors the current air pollutant levels and tracks the long-term development of air quality in Switzerland. The monitoring network consists of 16 stations distributed throughout Switzerland: Basel Sternwarte St. Margarethen, Bern, Beromünster (replacing the former Lägern station since summer 2016), Chaumont, Davos, Dübendorf (replaced in 2020), Härkingen, Jungfraujoch, Lausanne, Lugano, Magadino, Payerne, Rigi, Sion, Tänikon, and Zurich. These locations reflect the most common air pollution situations in Switzerland, ranging from low to high levels of pollution. Despite the relatively small number of measurement points, a detailed picture of air quality in Switzerland can be obtained.
Some of the stations are part of international measurement programs, namely the European Monitoring and Evaluation Programme (EMEP) and the Global Atmosphere Watch (GAW).
|
https://en.wikipedia.org/wiki/Eye%20movement%20in%20music%20reading | Eye movement in music reading is the scanning of a musical score by a musician's eyes. This usually occurs as the music is read during performance, although musicians sometimes scan music silently to study it. The phenomenon has been studied by researchers from a range of backgrounds, including cognitive psychology and music education. These studies have typically reflected a curiosity among performing musicians about a central process in their craft, and a hope that investigating eye movement might help in the development of more effective methods of training musicians' sight reading skills.
A central aspect of music reading is the sequence of alternating saccades and fixations, as it is for most oculomotor tasks. Saccades are the rapid ‘flicks’ that move the eyes from location to location over a music score. Saccades are separated from each other by fixations, during which the eyes are relatively stationary on the page. It is well established that the perception of visual information occurs almost entirely during fixations and that little if any information is picked up during saccades. Fixations comprise about 90% of music reading time, typically averaging 250–400 ms in duration.
Eye movement in music reading is an extremely complex phenomenon that involves a number of unresolved issues in psychology, and which requires intricate experimental conditions to produce meaningful data. Despite some 30 studies in this area over the past 70 years, little is known about the underlying patterns of eye movement in music reading.
Relationship with eye movement in language reading
Eye movement in music reading may at first appear to be similar to that in language reading, since in both activities the eyes move over the page in fixations and saccades, picking up and processing coded meanings. However, it is here that the obvious similarities end. Not only is the coding system of music nonlinguistic; it involves what is apparently a unique combination of features among hu |
https://en.wikipedia.org/wiki/Fano%20resonance | In physics, a Fano resonance is a type of resonant scattering phenomenon that gives rise to an asymmetric line-shape. Interference between a background and a resonant scattering process produces the asymmetric line-shape. It is named after Italian-American physicist Ugo Fano, who in 1961 gave a theoretical explanation for the scattering line-shape of inelastic scattering of electrons from helium; however, Ettore Majorana was the first to discover this phenomenon. Fano resonance is a weak coupling effect meaning that the decay rate is so high, that no hybridization occurs. The coupling modifies the resonance properties such as spectral position and width and its line-shape takes on the distinctive asymmetric Fano profile. Because it is a general wave phenomenon, examples can be found across many areas of physics and engineering.
History
The explanation of the Fano line-shape first appeared in the context of inelastic electron scattering by helium and autoionization. The incident electron doubly excites the atom to the state, a sort of shape resonance. The doubly excited atom spontaneously decays by ejecting one of the excited electrons. Fano showed that interference between the amplitude to simply scatter the incident electron and the amplitude to scatter via autoionization creates an asymmetric scattering line-shape around the autoionization energy with a line-width very close to the inverse of the autoionization lifetime.
Explanation
The Fano resonance line-shape is due to interference between two scattering amplitudes, one due to scattering within a continuum of states (the background process) and the second due to an excitation of a discrete state (the resonant process). The energy of the resonant state must lie in the energy range of the continuum (background) states for the effect to occur. Near the resonant energy, the background scattering amplitude typically varies slowly with energy while the resonant scattering amplitude changes both in magnitude and |
https://en.wikipedia.org/wiki/Biophilic%20design | Biophilic design is a concept used within the building industry to increase occupant connectivity to the natural environment through the use of direct nature, indirect nature, and space and place conditions. Used at both the building and city-scale, it is argued that this idea has health, environmental, and economic benefits for building occupants and urban environments, with few drawbacks. Although its name was coined in recent history, indicators of biophilic design have been seen in architecture from as far back as the Hanging Gardens of Babylon.
Biophilia hypothesis
The word “Biophilia” was first introduced by a psychoanalyst named Erich Fromm who stated that biophilia is the “passionate love of life and of all that is alive…whether in a person, a plant, an idea, or a social group” in his book The Anatomy of Human Destructiveness in 1973. Fromm's approach was that of a psychoanalyst (a person who studies the unconscious mind) and presented a broad spectrum as he called biophilia a biologically normal instinct.
The term has been used since by many scientists, and philosophers overall being adapted to several different areas of study. Some notable mentions of biophilia include Edward O. Wilson's book Biophilia (1984) where he took a biologist's approach and first coined the “Biophilia hypothesis” and popularized the notion. Wilson defined biophilia as “the innate tendency to focus on life and lifelike processes”, claiming a link with nature is not only physiological (as Fromm suggested) but has a genetic basis. The biophilia hypothesis is the idea that humans have an inherited need to connect to nature and other biotic forms due to our evolutionary dependence on it for survival and personal fulfillment. This idea is relevant in daily life – humans travel and spend money to sightsee in national parks and nature preserves, relax on beaches, hike mountains, and explore jungles. Further, many sports revolve around nature such as skiing, mountain biking, and surfin |
https://en.wikipedia.org/wiki/Steve%20Evets | Steve Evets (born Steven Murphy; 26 July 1959) is an English actor and musician, who found fame for his leading role in the 2009 film Looking for Eric.
Personal life
Born in Salford, Lancashire, Evets joined the Merchant Navy after leaving school, but was kicked out after three years, after jumping ship twice in Japan and spending his eighteenth birthday in a Bombay brothel.
In 1987 Evets was injured in a pub brawl and spent time on a life support machine. He was stabbed through the liver, lung and diaphragm, was glassed in the face and had his throat cut.
Evets briefly worked delivering pipes alongside his acting career, and as an electrician. As there was already a Steve Murphy on the books of Equity, he decided on the palindromic stage name Steve Evets, "The first thing that popped into my head was 'Steve' backwards ... so I put that on the form."
Career
Evets's early acting work included a street theatre company formed with two friends. He moved into theatre work, and had small roles in several television series such as See No Evil: The Moors Murders, Casualty, Life on Mars, The Cops, Shameless, and Emmerdale.
In between acting roles, he worked under the name Adolph Chip-pan, performing political comedy poetry in Manchester. He also worked as a musician, and was introduced to Mark E. Smith of the Fall in the mid-1990s, leading to Evets performing his poetry at some Fall gigs. When Smith found that Evets could play bass guitar, he was drafted into the band in Turkey after previous bassist Jim Watts had been sacked. Evets played in The Fall between 2000 and 2002, before leaving to front his own band, Dr Freak's Padded Cell, which he described as "electronic dance music with sort of very political overtones", even getting Smith to provide guest vocals on one track; Evets made a video for the track and posted it on YouTube, much to the dislike of Smith, ending their friendship.
His first major film role came in 2008, playing a terminally-ill alcoholic who uses |
https://en.wikipedia.org/wiki/Reserpine | Reserpine is a drug that is used for the treatment of high blood pressure, usually in combination with a thiazide diuretic or vasodilator. Large clinical trials have shown that combined treatment with reserpine plus a thiazide diuretic reduces mortality of people with hypertension. Although the use of reserpine as a solo drug has declined since it was first approved by the FDA in 1955, the combined use of reserpine and a thiazide diuretic or vasodilator is still recommended in patients who do not achieve adequate lowering of blood pressure with first-line drug treatment alone. The reserpine-hydrochlorothiazide combo pill was the 17th most commonly prescribed of the 43 combination antihypertensive pills available In 2012.
The antihypertensive actions of reserpine are largely due to its antinoradrenergic effects, which are a result of its ability to deplete catecholamines (among other monoamine neurotransmitters) from peripheral sympathetic nerve endings. These substances are normally involved in controlling heart rate, force of cardiac contraction and peripheral vascular resistance.
At doses of 0.05 to 0.2 mg per day, reserpine is well tolerated; the most common adverse effect being nasal stuffiness.
Reserpine has also been used for relief of psychotic symptoms. A review found that in persons with schizophrenia, reserpine and chlorpromazine had similar rates of adverse effects, but that reserpine was less effective than chlorpromazine for improving a person's global state.
Uses
Medical usage
Reserpine is recommended as an alternative drug for treating hypertension by the JNC 8. A 2016 Cochrane review found reserpine to be as effective as other first-line antihypertensive drugs for lowering of blood pressure. The reserpine–thiazide diuretic combination is one of the few drug treatments shown to reduce mortality in randomized controlled trials: The Hypertension Detection and Follow-up Program, the Veterans Administration Cooperative Study Group in Anti-hypertensiv |
https://en.wikipedia.org/wiki/Verastem%20Oncology | Verastem Oncology (Verastem Inc) is an American pharmaceutical company that develops medicines to treat certain cancers. Headquartered and founded in Boston, Massachusetts, the firm is a member of NASDAQ Biotechnology Index.
History
Verastem Oncology (Verastem Inc) was co-founded in 2010 by entrepreneur Christoph H. Westphal and venture capitalist Michelle Dipp, who provided seed funding and initial office space in Cambridge, MA. The company was formed to commercialize the work of the three other co-founders, MIT biologists Robert F. Weinberg, Eric S. Lander and Piyush Gupta, by discovering and developing drugs to treat cancer by targeting cancer stem cells.
The company raised $16 million in the initial Series A financing.
Westphal served as CEO and chairman of the board from 2010 to 2013. Under his leadership, the company raised $55 million through an IPO in 2012. Mr. Robert Forrester succeeded Christoph Westphal as Verastem's president and CEO in 2013. In July 2019, Brian Stuglik was appointed to chief executive officer (CEO) of Verastem Oncology.
Pipeline
Their leading investigational drug is defactinib (VS-6063), is a small-molecule focal adhesion kinase (FAK) inhibitor designed to kill cancer stem cells, intended for the treatment of malignant pleural mesothelioma. In October 2015, they announced the premature termination of the company's late-stage clinical trial for defactinib after data analysis of the Phase II COMMAND trial found no significant differences in efficacy versus placebo. . Following the failure of the study, the company had to cut 50% of its workforce.
In November 2016, Verastem Oncology licensed global rights from Infinity Pharmaceuticals to duvelisib (IPI-145), a novel inhibitor of PI3K delta and gamma. In April 2018, Verastem filed a New Drug Application (NDA) for duvelisib for the treatment of relapsed or refractory chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) and accelerated approval for relapsed or refract |
https://en.wikipedia.org/wiki/Spectral%20density%20estimation | In statistical signal processing, the goal of spectral density estimation (SDE) or simply spectral estimation is to estimate the spectral density (also known as the power spectral density) of a signal from a sequence of time samples of the signal. Intuitively speaking, the spectral density characterizes the frequency content of the signal. One purpose of estimating the spectral density is to detect any periodicities in the data, by observing peaks at the frequencies corresponding to these periodicities.
Some SDE techniques assume that a signal is composed of a limited (usually small) number of generating frequencies plus noise and seek to find the location and intensity of the generated frequencies. Others make no assumption on the number of components and seek to estimate the whole generating spectrum.
Overview
Spectrum analysis, also referred to as frequency domain analysis or spectral density estimation, is the technical process of decomposing a complex signal into simpler parts. As described above, many physical processes are best described as a sum of many individual frequency components. Any process that quantifies the various amounts (e.g. amplitudes, powers, intensities) versus frequency (or phase) can be called spectrum analysis.
Spectrum analysis can be performed on the entire signal. Alternatively, a signal can be broken into short segments (sometimes called frames), and spectrum analysis may be applied to these individual segments. Periodic functions (such as ) are particularly well-suited for this sub-division. General mathematical techniques for analyzing non-periodic functions fall into the category of Fourier analysis.
The Fourier transform of a function produces a frequency spectrum which contains all of the information about the original signal, but in a different form. This means that the original function can be completely reconstructed (synthesized) by an inverse Fourier transform. For perfect reconstruction, the spectrum analyzer m |
https://en.wikipedia.org/wiki/CD137 | CD137, a member of the tumor necrosis factor (TNF) receptor family, is a type 1 transmembrane protein, expressed on surfaces of leukocytes and non-immune cells. Its alternative names are tumor necrosis factor receptor superfamily member 9 (TNFRSF9), 4-1BB, and induced by lymphocyte activation (ILA). It is of interest to immunologists as a co-stimulatory immune checkpoint molecule, and as a potential target in cancer immunotherapy.
Expression
CD137 is only expressed on the cell surface after T cell activation. When T cells are activated by Antigen Presenting Cells (APCs), CD137 becomes embedded in CD4+ and CD8+ T cells.
CD137 is a costimulatory molecule functioning to stimulate T cell proliferation, dendritic cell maturation, and promotion of B cell antibody secretion. As a T cell co-stimulator, T cell receptor (TCR) and CD28 signaling causes expression of CD137 on T cell membranes. When CD137 then reacts with the CD137 ligand, it leads to CD137 upregulation. This is a form of self regulation or positive feedback cycle. When CD137 interacts with its ligand, it leads to T cell cytokine production and T cell proliferation, among other signaling pathway responses.
Other cells that express CD137 include both immune cells (i.e. monocytes, natural killer cells, dendritic cells, follicular dendritic cells (FDCs), and regulatory T cells) and non-immune cells (i.e. chondrocytes, neurons, astrocytes, microglia and endothelial cells).
Regulation of the immune system
CD137 and its ligand both induce signaling cascades upon interaction, a phenomenon known as bidirectional signal transduction. The CD137/ligand complex is also involved in regulation of the immune system. The CD137 ligand is a type-II transmembrane glycoprotein expressed on APCs. The CD137 ligand is normally expressed at low levels, but can have increased expression in presence of pathogen associated molecular patterns (PAMPs) or proinflammatory immune responses like IL-1 secretion.
Cross-linking CD137 and a |
https://en.wikipedia.org/wiki/Skin%20fold | Skin folds or skinfolds are areas of skin that are naturally folded. Many skin folds are distinct, heritable anatomical features, and may be used for identification of animal species, while others are non-specific and may be produced either by individual development of an organism or by arbitrary application of force to skin, either by the actions of the muscles of the body or by external force, e.g., gravity. Anatomical folds can also be found in other structures and tissues besides the skin, such as the ileocecal fold beneath the terminal ileum of the cecum.
Skin folds are of interest for cosmetology, as some kinds may be considered aesthetically undesirable, and for medicine, because some of them are susceptible to inflammation and infection.
Skin creases, skin folds and lines
The skin creases of the human body are features of great anatomical, morphological, and surgical interest and important for the maintenance of the contour of each anatomic area.
In the literature, when referring to a skin crease, there is variation of terms used other than "crease", such as "fold" and "sulcus", but these terms do not accurately reflect their histology structure nor their function. In the review of literature, a record of the creases of the human body for each anatomic area, including the synonyms that are used for each crease in the literature, has been attempted.
The skin crease as a fixed and permanent line, according to their histology, is related to connective tissue attachments with the underlying structures or extensions of the underlying muscle fibers in the dermis of the crease site.
The skin fold is characterized by skin redundancy that is responsible partly, often in combination with connective tissue attachments, for the skin crease. It is essential to use appropriate terms that accurately reflect the anatomic structure and histology when referring to the skin lines.
Human skin folds
The following distinct skin fold types are among the roughly 100 ide |
https://en.wikipedia.org/wiki/Wendelin%20Werner | Wendelin Werner (born 23 September 1968) is a German-born French mathematician working on random processes such as self-avoiding random walks, Brownian motion, Schramm–Loewner evolution, and related theories in probability theory and mathematical physics. In 2006, at the 25th International Congress of Mathematicians in Madrid, Spain he received the Fields Medal "for his contributions to the development of stochastic Loewner evolution, the geometry of two-dimensional Brownian motion, and conformal field theory". He is currently Rouse Ball professor of Mathematics at the University of Cambridge.
Biography
Werner was born on 23 September 1968 in Cologne, West Germany. His parents moved to France when he was nine months old and he became a French citizen in 1977. After a classe préparatoire at Lycée Hoche in Versailles, he studied at École Normale Supérieure from 1987 to 1991. His 1993 doctorate was written at the Université Pierre-et-Marie-Curie and supervised by Jean-François Le Gall. Werner was a researcher at the CNRS (National Center of Scientific Research, Centre national de la recherche scientifique) from 1991 to 1997, during which he also held a two-year Leibniz Fellowship, at the University of Cambridge. He was Professor at
the University of Paris-Sud from 1997 to 2013 and also taught at the École Normale Supérieure from 2005 to 2013. He was then Professor at the ETH Zürich from 2013 to 2023.
Awards and honors
Werner has received several awards besides the Fields Medal, including the Rollo Davidson Prize in 1998, the Prix Paul Doistau–Émile Blutet in 1999, the Fermat Prize in 2001, the Grand Prix Jacques Herbrand of the French Academy of Sciences in 2003, the Loève Prize in 2005, the 2006 SIAM George Pólya Prize with his collaborators Gregory Lawler and Oded Schramm, and the Heinz Gumin Prize (de) in 2016.
He became a member of the French Academy of Sciences in 2008. He is also a member of other academies of sciences, including the Academy of Sciences L |
https://en.wikipedia.org/wiki/Vegetation | Vegetation is an assemblage of plant species and the ground cover they provide. It is a general term, without specific reference to particular taxa, life forms, structure, spatial extent, or any other specific botanical or geographic characteristics. It is broader than the term flora which refers to species composition. Perhaps the closest synonym is plant community, but vegetation can, and often does, refer to a wider range of spatial scales than that term does, including scales as large as the global. Primeval redwood forests, coastal mangrove stands, sphagnum bogs, desert soil crusts, roadside weed patches, wheat fields, cultivated gardens and lawns; all are encompassed by the term vegetation.
The vegetation type is defined by characteristic dominant species, or a common aspect of the assemblage, such as an elevation range or environmental commonality. The contemporary use of vegetation approximates that of ecologist Frederic Clements' term earth cover, an expression still used by the Bureau of Land Management.
History of definition
The distinction between vegetation (the general appearance of a community) and flora (the taxonomic composition of a community) was first made by Jules Thurmann (1849). Prior to this, the two terms (vegetation and flora) were used indiscriminately, and still are in some contexts. Augustin de Candolle (1820) also made a similar distinction but he used the terms "station" (habitat type) and "habitation" (botanical region). Later, the concept of vegetation would influence the usage of the term biome with the inclusion of the animal element.
Other concepts similar to vegetation are "physiognomy of vegetation" (Humboldt, 1805, 1807) and "formation" (Grisebach, 1838, derived from "Vegetationsform", Martius, 1824).
Departing from Linnean taxonomy, Humboldt established a new science, dividing plant geography between taxonomists who studied plants as taxa and geographers who studied plants as vegetation. The physiognomic approach in the s |
https://en.wikipedia.org/wiki/Indian%20Physical%20Society | The Indian Physical Society is a professional society of physicists in India. It was formally established in 1934 by pioneering Indian physicist Meghnad Saha. The society's stated objectives are to promote the progress and uphold the cause of both pure and applied physics in India, to encourage publications in physics and related areas, to publish books, journals, proceedings etc., to organize conferences, advise government bodies, and to secure and administer funds, grants and endowments for the furtherance of scientific research.
Its headquarters are at the Indian Association for the Cultivation of Science in Kolkata, India. |
https://en.wikipedia.org/wiki/Form%20factor%20%28design%29 | Form factor is a hardware design aspect that defines and prescribes the size, shape, and other physical specifications of components, particularly in electronics. A form factor may represent a broad class of similarly sized components, or it may prescribe a specific standard. It may also define an entire system, as in a computer form factor.
Evolution and standardization
As electronic hardware has become smaller following Moore's law and related patterns, ever-smaller form factors have become feasible. Specific technological advances, such as PCI Express, have had a significant design impact, though form factors have historically evolved slower than individual components. Standardization of form factors is vital for hardware compatibility between different manufacturers.
Trade-offs
Smaller form factors may offer more efficient use of limited space, greater flexibility in the placement of components within a larger assembly, reduced use of material, and greater ease of transportation and use. However, smaller form factors typically incur greater costs in the design, manufacturing, and maintenance phases of the engineering lifecycle, and do not allow the same expansion options as larger form factors. In particular, the design of smaller form-factor computers and network equipment must entail careful consideration of cooling. End-user maintenance and repair of small form-factor electronic devices such as mobile phones is often not possible, and may be discouraged by warranty voiding clauses; such devices require professional servicing—or simply replacement—when they fail.
Examples
Computer form factors comprise a number of specific industry standards for motherboards, specifying dimensions, power supplies, placement of mounting holes and ports, and other parameters. Other types of form factors for computers include:
Small form factor (SFF), a more loosely defined set of standards that may refer to both motherboards and computer cases. SFF devices include mini-towe |
https://en.wikipedia.org/wiki/Enterovirus%20C | Enterovirus C is a species of enterovirus. Its best known subtype is poliovirus, the cause of poliomyelitis. There are three serotypes of poliovirus, PV1, PV2, and PV3. Other subtypes of Enterovirus C include EV-C95, EV-C96, EV-C99, EV-C102, EV-C104, EV-C105, EV-C109, EV-C116, EV-C117, and EV-C118. Some non-polio types of Enterovirus C have been associated with the polio-like condition AFP (acute flaccid paralysis), including 2 isolates of EV-C95 from Chad. |
https://en.wikipedia.org/wiki/Tonelli%E2%80%93Shanks%20algorithm | The Tonelli–Shanks algorithm (referred to by Shanks as the RESSOL algorithm) is used in modular arithmetic to solve for r in a congruence of the form r2 ≡ n (mod p), where p is a prime: that is, to find a square root of n modulo p.
Tonelli–Shanks cannot be used for composite moduli: finding square roots modulo composite numbers is a computational problem equivalent to integer factorization.
An equivalent, but slightly more redundant version of this algorithm was developed by
Alberto Tonelli
in 1891. The version discussed here was developed independently by Daniel Shanks in 1973, who explained:
My tardiness in learning of these historical references was because I had lent Volume 1 of Dickson's History to a friend and it was never returned.
According to Dickson, Tonelli's algorithm can take square roots of x modulo prime powers pλ apart from primes.
Core ideas
Given a non-zero and a prime (which will always be odd), Euler's criterion tells us that has a square root (i.e., is a quadratic residue) if and only if:
.
In contrast, if a number has no square root (is a non-residue), Euler's criterion tells us that:
.
It is not hard to find such , because half of the integers between 1 and have this property. So we assume that we have access to such a non-residue.
By (normally) dividing by 2 repeatedly, we can write as , where is odd. Note that if we try
,
then . If , then is a square root of . Otherwise, for , we have and satisfying:
; and
is a -th root of 1 (because ).
If, given a choice of and for a particular satisfying the above (where is not a square root of ), we can easily calculate another and for such that the above relations hold, then we can repeat this until becomes a -th root of 1, i.e., . At that point is a square root of .
We can check whether is a -th root of 1 by squaring it times and check whether it is 1. If it is, then we do not need to do anything, as the same choice of and works. But if it is not, must |
https://en.wikipedia.org/wiki/Colin%20Pask | Colin Pask (born 1943) is a British mathematical physicist and science writer.
Life
He was born in Great Gonerby, on the outskirts of Grantham in Lincolnshire, where his father was a dairy farmer. He was educated at King's School, Grantham from age 11, and went to Queen Mary College, London for a degree course in theoretical physics and mathematics. He graduated B.Sc. there in 1964.
Career
Pask studied for a Ph.D. in nuclear physics under John M. Blatt at the University of New South Wales from 1964, graduating in 1967 with a dissertation entitled Studies in the Nuclear Three-Body Problem. He spent a period at Duke University, then returned to the University of New South Wales as lecturer in the Department of Applied Mathematics.
In 1971 Pask moved to the Australian National University, with an Australian Research Council fellowship to work in the Department of Applied Mathematics there. He was made a Fellow in 1973, and Senior Fellow in 1978. He moved in 1986 to become head of University College at UNSW Canberra at ADFA, retiring from that post after 12 years.
Pask is now Emeritus Professor of Mathematical Sciences and History at University of New South Wales.
Research interests
As a post-doctoral researcher, Pask turned to optical physics and biological vision, among other topics. In 1973 he published with Allan Snyder an optical waveguide explanation of the Stiles–Crawford effect. Pask and McIntyre reviewed the theory and experimental results in the area, in a survey from 2013. Work of Pask and Kevin Barrell from 1980 contributed to the theory of the apposition eye.
During the 1970s, Pask also published on attenuation effects in optical fibres. He collaborated in this area with Adrian Ankiewicz.
Works
Pask has written some works of popularisation:
Math for the Frightened: Facing Scary Symbols and Everything Else That Freaks You Out About Mathematics (2011)
Magnificent Principia: Exploring Isaac Newton's Masterpiece (2013)
Great Calculations: A Surp |
https://en.wikipedia.org/wiki/Maths%20Week%20Ireland | Maths Week Ireland (MWI) is an all-island (Republic of Ireland and Northern Ireland) mathematics outreach initiative founded in 2006 by Eoin Gill and Sheila Donegan, based on an idea by Eoin Gill. It is a project of the Centre for the Advancement of Learning of Maths, Science and Technology (CALMAST) the STEM outreach centre at Waterford Institute of Technology. It is run by Gill and Donegan who are the directors of CALMAST. In 2019 MWI engaged over 400,000 people on an island with a population of under 7 million and is arguably the world's largest mathematics festival.
Purpose
MWI is a partnership of over 50 organizations dedicated to promoting and celebrating mathematics across the island of Ireland, including universities, institutes of technology, colleges, museums, libraries, visitor centres, and other professional bodies. Maths Week Ireland is supported by the Departments of Education in both parts of the island of Ireland, Science Foundation Ireland (SFI), the ESB Group, and various technology companies such as Google and Xilinx.
MWI targets school and universities, as well as hosting weekend "street fairs" in cities such as Dublin, Belfast and Cork. Events are run by the participants with materials delivered online by Maths Week Ireland. Most schools run their own special activities. Maths Week is a nine-day event (a Saturday to the Sunday of the following weekend, inclusive) which always includes the 16th of October, the day in 1843 when William R. Hamilton discovered quaternions.
The idea has been so successful that it has now been replicated in England and Scotland.
MWI hosts the Maths Ireland website which is home to the monthly blogs of the Annals of Irish Mathematics & Mathematicians (AIMM), authored by Colm Mulcahy.
Starting in 2016, MWI has also produced the annual Irish Maths Calendars which are also archived at the Maths Ireland site.
Presenters
Mathematicians and mathematics popularizers who have been MWI presenters include:
Rob Eastaway
|
https://en.wikipedia.org/wiki/Gamestar%20Mechanic | Gamestar Mechanic is an online game and community designed to teach the guiding principles of game design and systems thinking. The game is published by E-Line Media and supported by a partnership between E-Line Media and the Institute of Play.
Project history
Initial development of Gamestar was supported by a grant from the John D. and Catherine T. MacArthur Foundation based on a grant proposal authored by James Paul Gee and Eric Zimmerman. Initial design and development of the game was by Gamelab in partnership with Katie Salen, The Institute of Play and the Academic Advanced Distributed Learning Co-Lab (AADLC) at the University of Wisconsin–Madison. The game was released commercially in the Fall of 2010 and is currently supported by a partnership between educational game publisher E-Line Media and the Institute of Play.
On September 29, 2020, it was announced that the current website would be shut down on December 31, 2020, due to the planned deprecation of Adobe Flash. However, on November 20, 2020, it was instead announced that the game would remain available as a downloadable desktop application. The desktop application was released on December 15, 2020 and can be downloaded from the original website.
Audience and game play
The game is optimized for youth ages 8–14. Players learn the principles of game design by playing a narrative-based Quest where they play, repair and build games using the in-game design tools. As they advance in the Quest, players also earn "sprites" (characters, avatars, enemies, etc...) for use in their own games. At any time, players can switch to their Workshops and make an original game using the assets they have earned. Players can publish their games to an online community within the platform called Game Alley where other users can play and leave feedback on their games.
Playing on the website, now app, is free of charge, but there were once premium, now free, options available for both consumer and educational use.
An online |
https://en.wikipedia.org/wiki/Spectral%20radius | In mathematics, the spectral radius of a square matrix is the maximum of the absolute values of its eigenvalues. More generally, the spectral radius of a bounded linear operator is the supremum of the absolute values of the elements of its spectrum. The spectral radius is often denoted by .
Definition
Matrices
Let be the eigenvalues of a matrix . The spectral radius of is defined as
The spectral radius can be thought of as an infimum of all norms of a matrix. Indeed, on the one hand, for every natural matrix norm ; and on the other hand, Gelfand's formula states that . Both of these results are shown below.
However, the spectral radius does not necessarily satisfy for arbitrary vectors . To see why, let be arbitrary and consider the matrix
.
The characteristic polynomial of is , so its eigenvalues are and thus . However, . As a result,
As an illustration of Gelfand's formula, note that as , since if is even and if is odd.
A special case in which for all is when is a Hermitian matrix and is the Euclidean norm. This is because any Hermitian Matrix is diagonalizable by a unitary matrix, and unitary matrices preserve vector length. As a result,
Bounded linear operators
In the context of a bounded linear operator on a Banach space, the eigenvalues need to be replaced with the elements of the spectrum of the operator, i.e. the values for which is not bijective. We denote the spectrum by
The spectral radius is then defined as the supremum of the magnitudes of the elements of the spectrum:
Gelfand's formula, also known as the spectral radius formula, also holds for bounded linear operators: letting denote the operator norm, we have
A bounded operator (on a complex Hilbert space) is called a spectraloid operator if its spectral radius coincides with its numerical radius. An example of such an operator is a normal operator.
Graphs
The spectral radius of a finite graph is defined to be the spectral radius of its adjacency matrix.
This definit |
https://en.wikipedia.org/wiki/List%20of%20accelerators%20in%20particle%20physics | A list of particle accelerators used for particle physics experiments. Some early particle accelerators that more properly did nuclear physics, but existed prior to the separation of particle physics from that field, are also included. Although a modern accelerator complex usually has several stages of accelerators, only accelerators whose output has been used directly for experiments are listed.
Early accelerators
These all used single beams with fixed targets. They tended to have very briefly run, inexpensive, and unnamed experiments.
Cyclotrons
[1] The magnetic pole pieces and return yoke from the 60-inch cyclotron were later moved to UC Davis and incorporated into a 76-inch isochronous cyclotron which is still in use today
Other early accelerator types
Synchrotrons
Fixed-target accelerators
More modern accelerators that were also run in fixed target mode; often, they will also have been run as colliders, or accelerated particles for use in subsequently built colliders.
High intensity hadron accelerators (Meson and neutron sources)
Electron and low intensity hadron accelerators
Colliders
Electron–positron colliders
Hadron colliders
Electron-proton colliders
Light sources
Hypothetical accelerators
Besides the real accelerators listed above, there are hypothetical accelerators often used
as hypothetical examples or optimistic projects by particle physicists.
Eloisatron (Eurasiatic Long Intersecting Storage Accelerator) was a project of INFN headed by Antonio Zichichi at the Ettore Majorana Foundation and Centre for Scientific Culture in Erice, Sicily. The center-of-mass energy was planned to be 200 TeV, and the size was planned to span parts of Europe and Asia.
Fermitron was an accelerator sketched by Enrico Fermi on a notepad in the 1940s proposing an accelerator in stable orbit around the Earth.
The undulator radiation collider is a design for an accelerator with a center-of-mass energy around the GUT scale. It would be light-weeks across a |
https://en.wikipedia.org/wiki/Maximum%20satisfiability%20problem | In computational complexity theory, the maximum satisfiability problem (MAX-SAT) is the problem of determining the maximum number of clauses, of a given Boolean formula in conjunctive normal form, that can be made true by an assignment of truth values to the variables of the formula. It is a generalization of the Boolean satisfiability problem, which asks whether there exists a truth assignment that makes all clauses true.
Example
The conjunctive normal form formula
is not satisfiable: no matter which truth values are assigned to its two variables, at least one of its four clauses will be false.
However, it is possible to assign truth values in such a way as to make three out of four clauses true; indeed, every truth assignment will do this.
Therefore, if this formula is given as an instance of the MAX-SAT problem, the solution to the problem is the number three.
Hardness
The MAX-SAT problem is OptP-complete, and thus NP-hard, since its solution easily leads to the solution of the boolean satisfiability problem, which is NP-complete.
It is also difficult to find an approximate solution of the problem, that satisfies a number of clauses within a guaranteed approximation ratio of the optimal solution. More precisely, the problem is APX-complete, and thus does not admit a polynomial-time approximation scheme unless P = NP.
Weighted MAX-SAT
More generally, one can define a weighted version of MAX-SAT as follows: given a conjunctive normal form formula with non-negative weights assigned to each clause, find truth values for its variables that maximize the combined weight of the satisfied clauses. The MAX-SAT problem is an instance of weighted MAX-SAT where all weights are 1.
Approximation algorithms
1/2-approximation
Randomly assigning each variable to be true with probability 1/2 gives an expected 2-approximation. More precisely, if each clause has at least variables, then this yields a (1 − 2−)-approximation. This algorithm can be derandomized using the meth |
https://en.wikipedia.org/wiki/Lev%20Berg | Lev Semyonovich Berg, also known as Leo S. Berg (; 14 March 1876 – 24 December 1950) was a leading Russian geographer, biologist and ichthyologist who served as President of the Soviet Geographical Society between 1940 and 1950.
He is known for his own evolutionary theory, nomogenesis (a form of orthogenesis incorporating mutationism) as opposed to the theories of Darwin and Lamarck.
Life
Lev Berg was born in Bessarabia in a Jewish family, the son of Simon Gregoryevich Berg, a notary, and Klara Lvovna Bernstein-Kogan. He graduated from the Second Kishinev Gymnasium in 1894. Like some of his relatives, Berg converted to Christianity in order to pursue his studies at Moscow State University.
At Moscow University, Berg studied hydrobiology and geography. He later studied ichthyology and in 1928 was awarded he was also a member of the Russian Academy of Sciences.
Lev Berg graduated from the Moscow State University in 1898. Between 1903 and 1914, he worked in the Museum of Zoology in Saint Petersburg. He was one of the founders of the Geographical Institute, now a Faculty of Geography of the Saint Petersburg State University.
Berg studied and determined the depth of the lakes of Central Asia, including Balkhash and Issyk-Kul. He developed Dokuchaev's doctrine of natural zones, which became one of the foundations of the Soviet biology. Among his pioneering monographs on climatology were "Climate and Life" (1922) and "Foundations of Climatology" (1927).
During his lifetime, Berg was a towering presence in the science of ichthyology. In 1916, he published four volumes of the study of Fishes of Russia. The fourth edition was issued in 1949 as Freshwater Fishes of the Soviet Union and Adjacent Countries and won him the Stalin Prize. He was said to have discovered the symbiotic relationship between lampreys and salmon. Berg's name is featured in the Latin appellations of more than 60 species of plants and animals.
In 2001, the Central Bank of Transnistria minted a silv |
https://en.wikipedia.org/wiki/Ostiole | An ostiole is a small hole or opening through which algae or fungi release their mature spores.
The word is a diminutive of "ostium", "opening".
The term is also used in higher plants, for example to denote the opening of the involuted syconium (fig inflorescence) through which fig wasps enter to pollinate and breed.
Sometimes a stomatal aperture is called an "ostiole".
See also
Ostium (disambiguation) |
https://en.wikipedia.org/wiki/Quadratus%20lumborum%20muscle | The quadratus lumborum muscle, informally called the QL, is a paired muscle of the left and right posterior abdominal wall. It is the deepest abdominal muscle, and commonly referred to as a back muscle. Each is irregular and quadrilateral in shape.
The quadratus lumborum muscles originate from the wings of the ilium; their insertions are on the transverse processes of the upper four lumbar vertebrae plus the lower posterior border of the twelfth rib. Contraction of one of the pair of muscles causes lateral flexion of the lumbar spine, elevation of the pelvis, or both. Contraction of both causes extension of the lumbar spine.
A disorder of the quadratus lumborum muscles is pain due to muscle fatigue from constant contraction due to prolonged sitting, such as at a computer or in a car. Kyphosis and weak gluteal muscles can also contribute to the likelihood of quadratus lumborum pain.
Structure
The quadratus lumborum muscle originates by aponeurotic fibers into the iliolumbar ligament and the internal lip of the iliac crest for about . It inserts from the lower border of the last rib for about half its length and by four small tendons from the apices of the transverse processes of the upper four lumbar vertebrae.
The number of attachments to the vertebræ, and the extent of its attachment to the last rib, may vary. Also, occasionally, a second portion of this muscle is found in front of the preceding. It arises from the upper borders of the transverse processes of the lower three or four lumbar vertebræ, and is inserted into the lower margin of the last rib.
Relationships
Anterior to the quadratus lumborum are the colon, the kidney, the psoas major muscle, (if present) the psoas minor muscle, and the diaphragm; between the fascia and the muscle are the twelfth thoracic, ilioinguinal, and iliohypogastric nerves. The quadratus lumborum muscle is a continuation of transverse abdominal muscle.
Nerve supply
Anterior branches of the ventral rami of T12 to L4.
Funct |
https://en.wikipedia.org/wiki/Gene-activated%20matrix | In gene-activated matrix technology (GAM), cytokines and growth factors could be delivered not as recombinant proteins but as plasmid genes. GAM is one of the tissue engineering approaches to wound healing. Following gene delivery, the recombinant cytokine could be expressed in situ by endogenous would healing cells – in small amounts but for a prolonged period of time – leading to reproducible tissue regeneration. |
https://en.wikipedia.org/wiki/Genetic%20Discrimination%20Observatory | The Genetic Discrimination Observatory (GDO) is a Montreal-based international network of researchers and other stakeholders who support the research and prevention of genetic discrimination (GD)—discrimination based on genetics or other predictive health information. Their headquarters are currently located at the Centre of Genomics and Policy at McGill University in Montreal.
Staff and funding
The GDO staff comes from various fields such as genetics, ethics, law, sociology, and public policy. The GDO received initial funding from Genome Canada (Génome Québec in French), the Fonds de recherche du Québec – Santé, and the Network of Applied Medical Genetics (RMGA).
Projects
Forum québécois sur la discrimination génétique
In 2018, the GDO initiated its first project, the "Forum québécois sur la discrimination génétique" (Quebec forum on genetic discrimination) in Quebec.
World views
The GDO provides information about different countries and areas using interactive world views that show studies related to genetic discrimination and other categories in a live map format on the GDO's website. It is planned to cover nineteen different jurisdictions.
Case reporting
The GDO provides individuals from Canada, Mexico, the United Kingdom and the United States the opportunity to report specific cases of genetic discrimination or health-based discrimination confidentially.
See also
Genetic discrimination |
https://en.wikipedia.org/wiki/Elixir%20sulfanilamide | Elixir sulfanilamide was an improperly prepared sulfonamide antibiotic that caused mass poisoning in the United States in 1937. It is believed to have killed more than 100 people. The public outcry caused by this incident and other similar disasters led to the passing of the 1938 Federal Food, Drug, and Cosmetic Act, which significantly increased the Food and Drug Administration's powers to regulate drugs.
History
Aside from the Pure Food and Drug Act of 1906 and the Harrison Act of 1914 banning the sale of some narcotic drugs, there was no federal regulatory control in the United States of America for drugs until Congress enacted the 1938 Food, Drug, and Cosmetic Act in response to the elixir sulfanilamide poisonings.
In 1937, S. E. Massengill Company, a pharmaceutical manufacturer, created an oral preparation of sulfanilamide using diethylene glycol (DEG) as the solvent or excipient, and called the preparation "Elixir Sulfanilamide". DEG is poisonous to humans and other mammals, but Harold Watkins, the company's chief pharmacist and chemist, was not aware of this. (Although the first case of a fatality from the related ethylene glycol occurred in 1930 and studies had been published in medical journals stating DEG could cause kidney damage or failure, its toxicity was not widely known prior to the incident.) Watkins simply mixed raspberry flavoring into the powdered drug and then dissolved the mixture in DEG. Animal testing was not required by law, and Massengill performed none; there were no regulations at the time requiring premarket safety testing of drugs.
The company started selling and distributing the medication in September 1937. By October 11, the American Medical Association received a report of several deaths caused by the medication. The Food and Drug Administration was notified, and an extensive search was conducted to recover the distributed medicine. Frances Oldham Kelsey assisted on a research project that verified that the DEG solvent was respo |
https://en.wikipedia.org/wiki/Body%20force | In physics, a body force is a force that acts throughout the volume of a body. Forces due to gravity, electric fields and magnetic fields are examples of body forces. Body forces contrast with contact forces or surface forces which are exerted to the surface of an object.
Fictitious forces such as the centrifugal force, Euler force, and the Coriolis effect are other examples of body forces.
Definition
Qualitative
A body force is simply a type of force, and so it has the same dimensions as force, [M][L][T]−2. However, it is often convenient to talk about a body force in terms of either the force per unit volume or the force per unit mass. If the force per unit volume is of interest, it is referred to as the force density throughout the system.
A body force is distinct from a contact force in that the force does not require contact for transmission. Thus, common forces associated with pressure gradients and conductive and convective heat transmission are not body forces as they require contact between systems to exist. Radiation heat transfer, on the other hand, is a perfect example of a body force.
More examples of common body forces include;
Gravity,
Electric forces acting on an object charged throughout its volume,
Magnetic forces acting on currents within an object, such as the braking force that results from eddy currents,
Fictitious forces (or inertial forces) can be viewed as body forces. Common inertial forces are,
Centrifugal force,
Coriolis force,
Euler force (or transverse force), which occurs in a rotating reference frame when the rate of rotation of the frame is changing
However, fictitious forces are not actually forces. Rather they are corrections to Newton's second law when it is formulated in an accelerating reference frame. (Gravity can also be considered a fictitious force in the context of General Relativity.)
Quantitative
The body force density is defined so that the volume integral (throughout a volume of interest) of it gives the total |
https://en.wikipedia.org/wiki/Chatbot | A chatbot (originally chatterbot) is a software application or web interface that aims to mimic human conversation through text or voice interactions. Modern chatbots are typically online and use artificial intelligence (AI) systems that are capable of maintaining a conversation with a user in natural language and simulating the way a human would behave as a conversational partner. Such technologies often utilize aspects of deep learning and natural language processing, but more simplistic chatbots have been around for decades prior.
Recently, this field has gained widespread attention due to the popularity of OpenAI's ChatGPT (using GPT-3 or GPT-4), released in 2022, followed by alternatives such as Microsoft's Bing Chat (which uses OpenAI's GPT-4) and Google's Bard. Such examples reflect the recent practice of such products being built based upon broad foundational large language models that get fine-tuned so as to target specific tasks or applications (i.e. simulating human conversation, in the case of chatbots). Chatbots can also be designed or customized to further target even more specific situations and/or particular subject-matter domains.
A major area where chatbots have long been used is in customer service and support, such as with various sorts of virtual assistants. Companies spanning various industries have begun using the latest generative artificial intelligence technologies to power more advanced developments in such areas.
Background
In 1950, Alan Turing's famous article "Computing Machinery and Intelligence" was published, which proposed what is now called the Turing test as a criterion of intelligence. This criterion depends on the ability of a computer program to impersonate a human in a real-time written conversation with a human judge to the extent that the judge is unable to distinguish reliably—on the basis of the conversational content alone—between the program and a real human. The notoriety of Turing's proposed test stimulated great i |
https://en.wikipedia.org/wiki/Phases%20of%20clinical%20research | The phases of clinical research are the stages in which scientists conduct experiments with a health intervention to obtain sufficient evidence for a process considered effective as a medical treatment. For drug development, the clinical phases start with testing for drug safety in a few human subjects, then expand to many study participants (potentially tens of thousands) to determine if the treatment is effective. Clinical research is conducted on drug candidates, vaccine candidates, new medical devices, and new diagnostic assays.
Description
Clinical trials testing potential medical products are commonly classified into four phases. The drug development process will normally proceed through all four phases over many years. When expressed specifically, a clinical trial phase is capitalized both in name and Roman numeral, such as "Phase I" clinical trial.
If the drug successfully passes through Phases I, II, and III, it will usually be approved by the national regulatory authority for use in the general population. Phase IV trials are 'post-marketing' or 'surveillance' studies conducted to monitor safety over several years.
Preclinical studies
Before clinical trials are undertaken for a candidate drug, vaccine, medical device, or diagnostic assay, the product candidate is tested extensively in preclinical studies. Such studies involve in vitro (test tube or cell culture) and in vivo (animal model) experiments using wide-ranging doses of the study agent to obtain preliminary efficacy, toxicity and pharmacokinetic information. Such tests assist the developer to decide whether a drug candidate has scientific merit for further development as an investigational new drug.
Phase 0
Phase 0 is a recent designation for optional exploratory trials conducted in accordance with the United States Food and Drug Administration's (FDA) 2006 Guidance on Exploratory Investigational New Drug (IND) Studies. Phase 0 trials are also known as human microdosing studies and are designe |
https://en.wikipedia.org/wiki/Streamium | Streamium was a line of IP-enabled entertainment products by Dutch electronics multi-national Philips Consumer Electronics. Streamium products use Wi-Fi to stream multimedia content from desktop computers or Internet-based services to home entertainment devices. A Streamium device plugged into the local home network will be able to see multimedia files that are in different UPnP-enabled computers, PDAs and other networking devices that run UPnP AV MediaServer software.
Streamium products may also support internet radio, internet photo sharing and movie trailers services directly. Subscriptions to web-based services requiring subscriptions would be managed through the 'Club Philips' portal.
In all cases, using a computer with RSS receiver together with a UPnP AV MediaServer, it is possible to play back audio/video podcast. Some of the popular feeds include BBC live, Geekbrief, Reuters, Metacafe, YouTube. Although in most cases this video podcaster uses codec formats not supported by Streamium, it's still possible by using software codec transcoders on the PC to convert them to MPEG format.
Philips Media Manager, is—since SimpleCenter version 4— a free open source UPnP AV MediaServer for Windows and Macintosh that is bundled with Streamium. Version 3 of SimpleCenter, was initially developed for inclusion with the Streamium line of products. Since Streamium devices also support photos and videos, SimpleCenter ships with video and image support, under the name 'Philips Media Manager' (PMM).
History
In 2000 Philips' consumer electronics division (business unit Audio) invented the Streamium brand for a "Connected Home". A number of products were released between January 2000 and June 2003. In 2003 the "Connected Home" would be broadened to the "Connected Planet" accompanied by an attempt to steer product development and industrialization from Eindhoven and to include other business units. The "Connected Planet" was less successful, leaving a limited number of product |
https://en.wikipedia.org/wiki/List%20of%20culinary%20fruits | This list contains the names of fruits that are considered edible either raw or cooked in various cuisines. The word "fruit" is used in several different ways. The definition of fruit for this list is a culinary fruit, that is, "Any edible and palatable part of a plant that resembles fruit, even if it does not develop from a floral ovary; also used in a technically imprecise sense for some sweet or semi-sweet vegetables, some of which may resemble a true fruit or are used in cookery as if they were a fruit, for example rhubarb." Many edible plant parts that are true fruits botanically speaking, are not considered culinary fruits. They are classified as vegetables in the culinary sense (for example: the tomato, zucchini, and so on), and hence they do not appear in this list. Similarly, some botanical fruits are classified as nuts (e.g. brazil nut), and do not appear here either. Even so, this list is otherwise organized botanically.
Pomes
Pomes include any crunchy accessory fruit that surrounds the fruit's inedible "core" (composed of the plant's endocarp) and typically has its seeds arranged in a star-like pattern.
Drupes
Drupes represent any fruit that has only one seed (or "stone") or one hard capsule containing seeds.
Botanical berries
Botanical berries represent any fruit that has a relatively thin exterior, with mostly flesh and more than one seed inside.
Pepos
Pepos represent any fruit that is covered by a hard, thick rind with soft flesh inside, and seeds filling each locule. Melons are good examples of this.
Hesperidiums
Also known as citruses, Hesperidiums possess thick and leathery rinds. These fruits are generally sour and acidic to some extent and have a wagon wheel-like cross section.
Aggregate fruits
Aggregate fruits are a cluster of many fruits produced from a single flower.
Multiple fruits
Multiple fruits are a cluster of many fruits produced from multiple flowers.
Capsules
Capsules represent a pod fruit with multiple carpels. |
https://en.wikipedia.org/wiki/Skewes%27s%20number | In number theory, Skewes's number is any of several large numbers used by the South African mathematician Stanley Skewes as upper bounds for the smallest natural number for which
where is the prime-counting function and is the logarithmic integral function. Skewes's number is much larger, but it is now known that there is a crossing between and near It is not known whether it is the smallest crossing.
Skewes's numbers
J.E. Littlewood, who was Skewes's research supervisor, had proved in that there is such a number (and so, a first such number); and indeed found that the sign of the difference changes infinitely many times. All numerical evidence then available seemed to suggest that was always less than Littlewood's proof did not, however, exhibit a concrete such number .
proved that, assuming that the Riemann hypothesis is true, there exists a number violating below
In , without assuming the Riemann hypothesis, Skewes proved that there must exist a value of below
Skewes's task was to make Littlewood's existence proof effective: exhibiting some concrete upper bound for the first sign change. According to Georg Kreisel, this was at the time not considered obvious even in principle.
More recent estimates
These upper bounds have since been reduced considerably by using large-scale computer calculations of zeros of the Riemann zeta function. The first estimate for the actual value of a crossover point was given by , who showed that somewhere between and there are more than consecutive integers with .
Without assuming the Riemann hypothesis, proved an upper bound of . A better estimate was discovered by , who showed there are at least consecutive integers somewhere near this value where . Bays and Hudson found a few much smaller values of where gets close to ; the possibility that there are crossover points near these values does not seem to have been definitely ruled out yet, though computer calculations suggest they are unlikely to exist. |
https://en.wikipedia.org/wiki/Tyrosine%20kinase%202 | Non-receptor tyrosine-protein kinase TYK2 is an enzyme that in humans is encoded by the TYK2 gene.
TYK2 was the first member of the JAK family that was described (the other members are JAK1, JAK2, and JAK3). It has been implicated in IFN-α, IL-6, IL-10 and IL-12 signaling.
Function
This gene encodes a member of the tyrosine kinase and, to be more specific, the Janus kinases (JAKs) protein families. This protein associates with the cytoplasmic domain of type I and type II cytokine receptors and promulgate cytokine signals by phosphorylating receptor subunits. It is also component of both the type I and type III interferon signaling pathways. As such, it may play a role in anti-viral immunity.
Cytokines play pivotal roles in immunity and inflammation by regulating the survival, proliferation, differentiation, and function of immune cells, as well as cells from other organ systems. Hence, targeting cytokines and their receptors is an effective means of treating such disorders. Type I and II cytokine receptors associate with Janus family kinases (JAKs) to affect intracellular signaling. Cytokines including interleukins, interferons and hemopoietins activate the Janus kinases, which associate with their cognate receptors.
The mammalian JAK family has four members: JAK1, JAK2, JAK3 and tyrosine kinase 2 (TYK2). The connection between Jaks and cytokine signaling was first revealed when a screen for genes involved in interferon type I (IFN-1) signaling identified TYK2 as an essential element, which is activated by an array of cytokine receptors. TYK2 has broader and profound functions in humans than previously appreciated on the basis of analysis of murine models, which indicate that TYK2 functions primarily in IL-12 and type I-IFN signaling. TYK2 deficiency has more dramatic effects in human cells than in mouse cells. However, in addition to IFN-α and -β and IL-12 signaling, TYK2 has major effects on the transduction of IL-23, IL-10, and IL-6 signals. Since, IL-6 si |
https://en.wikipedia.org/wiki/ALOHAnet | ALOHAnet, also known as the ALOHA System, or simply ALOHA, was a pioneering computer networking system developed at the University of Hawaii.
The ALOHAnet used a new method of medium access, called ALOHA random access, and experimental ultra high frequency (UHF) for its operation. In its simplest form, later known as Pure ALOHA, remote units communicated with a base station (Menehune) over two separate radio frequencies (for inbound and outbound respectively). Nodes did not wait for the channel to be clear before sending, but instead waited for acknowledgement of successful receipt of a message, and re-sent it if this was not received. Nodes would also stop and re-transmit data if they detected any other messages while transmitting. While simple to implement, this results in an efficiency of only 18.4%. A later advancement, Slotted ALOHA, improved the efficiency of the protocol by reducing the chance of collision, improving throughput to 36.8%.
ALOHAnet became operational in June 1971, providing the first public demonstration of a wireless packet data network.
ALOHA was subsequently employed in the Ethernet cable based network in the 1970s, and following regulatory developments in the early 1980s it became possible to use the ALOHA random-access techniques in both Wi-Fi and in mobile telephone networks. ALOHA channels were used in a limited way in the 1980s in 1G mobile phones for signaling and control purposes. In the late 1980s, the European standardization group GSM who worked on the Pan-European Digital mobile communication system GSM greatly expanded the use of ALOHA channels for access to radio channels in mobile telephony. In the early 2000s additional ALOHA channels were added to 2.5G and 3G mobile phones with the widespread introduction of General Packet Radio Service (GPRS), using a slotted-ALOHA random-access channel combined with a version of the Reservation ALOHA scheme first analyzed by a group at BBN Technologies.
History
One of the early compu |
https://en.wikipedia.org/wiki/List%20of%20statistical%20areas%20in%20Colorado | The U.S. State of Colorado has twenty-one statistical areas that have been delineated by the Office of Management and Budget (OMB). Statistical areas are important geographic delineations of population clusters used by the OMB, the United States Census Bureau, planning organizations, and federal, state, and local government entities.
On March 6, 2020, the OMB delineated four combined statistical areas, seven metropolitan statistical areas, and ten micropolitan statistical areas in Colorado. The most populous of these statistical areas is the Denver–Aurora, CO Combined Statistical Area, with a population of 3,623,560 at the 2020 census.
Statistical areas
The Office of Management and Budget (OMB) has designated more than 1,000 statistical areas across the United States and Puerto Rico.
The OMB defines a core-based statistical area (commonly referred to as a CBSA) as "a statistical geographic entity consisting of the county or counties (or county-equivalents) associated with at least one core of at least 10,000 population, plus adjacent counties having a high degree of social and economic integration with the core as measured through commuting ties with the counties containing the core." The OMB further divides core-based statistical areas into metropolitan statistical areas (MSAs), which have a population of at least 50,000, and micropolitan statistical areas (μSAs), which have a population of at least 10,000, but fewer than 50,000.
The OMB defines a combined statistical area (CSA) as "a geographic entity consisting of two or more adjacent core-based statistical areas with employment interchange measures of at least 15%".
Counties by statistical areas
Primary statistical areas
Primary statistical areas (PSAs) include all combined statistical areas and any core-based statistical area that is not a constituent of a combined statistical area. Of the 21 statistical areas of Colorado, 12 are PSAs comprising four combined statistical areas, three metropolitan statisti |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.