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https://en.wikipedia.org/wiki/Semantic%20audio | Semantic audio is the extraction of meaning from audio signals. The field of semantic audio is primarily based around the analysis of audio to create some meaningful metadata, which can then be used in a variety of different ways.
Semantic Analysis
Semantic analysis of audio is performed to reveal some deeper understanding of an audio signal. This typically results in high-level metadata descriptors such as musical chords and tempo, or the identification of the individual speaking, to facilitate content-based management of audio recordings. In recent years, the growth of automatic data analysis techniques has grown considerably,
Music Information Retrieval
Sound recognition
Speech segmentation
Automatic music transcription
Blind source separation
Musical similarity
Audio indexing, hashing, searching
Broadcast Monitoring
Musical performance analysis
Applications
With the development of applications that use this semantic information to support the user in identifying, organising, and exploring audio signals, and interacting with them. These applications include music information retrieval, semantic web technologies, audio production, sound reproduction, education, and gaming. Semantic technology involves some kind of understanding of the meaning of the information it deals with and to this end may incorporate machine learning, digital signal processing, speech processing, source separation, perceptual models of hearing, musicological knowledge, metadata, and ontologies.
Aside from audio retrieval and recommendation technologies, the semantics of audio signals are also becoming increasingly important, for instance, in object-based audio coding, as well as intelligent audio editing, and processing. Recent product releases already demonstrate this to a great extent, however, more innovative functionalities relying on semantic audio analysis and management are imminent. These functionalities may utilise, for instance, (informed) audio source separation, s |
https://en.wikipedia.org/wiki/Thrombospondin | Thrombospondins (TSPs) are a family of secreted glycoproteins with antiangiogenic functions. Due to their dynamic role within the extracellular matrix they are considered matricellular proteins. The first member of the family, thrombospondin 1 (THBS1), was discovered in 1971 by Nancy L. Baenziger.
Types
The thrombospondins are a family of multifunctional proteins. The family consists of thrombospondins 1-5 and can be divided into 2 subgroups: A, which contains TSP-1 and TSP-2, and B, which contains TSP-3, TSP-4 and TSP-5 (also designated cartilage oligomeric protein or COMP). TSP-1 and TSP-2 are homotrimers, consisting of three identical subunits, whereas TSP-3, TSP-4 and TSP-5 are homopentamers.
TSP-1 and TSP-2 are produced by immature astrocytes during brain development, which promotes the development of new synapses.
Thrombospondin 1
Thrombospondin 1 (TSP-1) is encoded by THBS1. It was first isolated from platelets that had been stimulated with thrombin, and so was designated 'thrombin-sensitive protein'. Since its first recognition, functions for TSP-1 have been found in multiple biological processes including angiogenesis, apoptosis, activation of TGF-beta and Immune regulation. As such, TSP-1 is designated a multifunctional protein.
TSP-1 has multiple receptors, among which CD36, CD47 and integrins are of particular note.
TSP-1 is antiangiogenic, inhibiting the proliferation and migration of endothelial cells by interactions with CD36 expressed on their surface of these cells. Inhibitory peptides and fragments of TSP1 bind to CD36, leading to the expression of FAS ligand (FasL), which activates its specific, ubiquitous receptor, Fas. This leads to the activation of caspases and apoptosis of the cell. Since tumors overexpressing TSP-1 typically grow slower, exhibit less angiogenesis, and have fewer metastases, TSP1 is an attractive target for cancer treatment. Because TSP1 is extremely large (~120 kDa monomer), not very abundant and exerts multiple actio |
https://en.wikipedia.org/wiki/List%20of%20software%20for%20the%20TRS-80 | The TRS-80 series of computers were sold via Radio Shack & Tandy dealers in North America and Europe in the early 1980s. Much software was developed for these computers, particularly the relatively successful Color Computer I, II & III models, which were designed for both home office and entertainment (gaming) uses.
A list of software for the TRS-80 computer series appears below. This list includes software that was sold labelled as a Radio Shack or Tandy product.#
Note: This List is by no means complete, especially with regards to the earlier non-color computer models.
Model I
Model II
VideoTex
Color Computer
TRS-80 Color Computer
Color Computer 1 & 2
Color Computer 3
Model III
Many of these titles also ran on the Model I, as the Model III was designed to be backward-compatible with the Model I.
Model 16 & 16B
Model 4, 4D & 4P
Model 12
MC-10
Model 100 & 102
TRS-80 software |
https://en.wikipedia.org/wiki/Allium%20paradoxum | Allium paradoxum, the few-flowered garlic or few-flowered leek, is an Asian species of wild onion in the Amaryllis family. It is native to mountainous regions of Iran, Caucasus, and Turkmenistan and invasive in Europe.
Description
Allium paradoxum is a herbaceous perennial growing from a small solitary bulb to about in height. It has much narrower leaves, from wide, than Allium ursinum but a similar 'garlicky' smell. The flower stem is triangular in section. Most of the flowers are replaced by little bulbs or bulbils and the few (usually only one) proper flowers are white and hermaphrodite.
Distribution
Allium paradoxum is native to mountainous regions of Iran, Caucasus, and Turkmenistan.
It was introduced to the British Isles in 1823 and was first recorded in the wild there in 1863, near Edinburgh. It is generally a lowland plant, and the highest record for Britain comes from Carter Bar at . It is considered an invasive, non-native species in Europe. In England and Wales, the species is listed on Schedule 9 of the Wildlife and Countryside Act and as such, it is illegal to plant in the wild. The smell of the plant is particularly noticeable to a person who is approaching an area where it is growing.
Habitat
It grows well in deciduous woodland habitats, forming a green carpet that can smother other native species such as bluebells and snowdrops. It also grows in a variety of habitats including river banks, rough pasture, field edges, roadsides and wasteground.
Cuisine
The few-flowered leek is edible and can be eaten raw as well as made into dishes. It can also be used as a herb to flavour food, much in the same way as other wild garlics. |
https://en.wikipedia.org/wiki/Wadge%20hierarchy | In descriptive set theory, within mathematics, Wadge degrees are levels of complexity for sets of reals. Sets are compared by continuous reductions. The Wadge hierarchy is the structure of Wadge degrees. These concepts are named after William W. Wadge.
Wadge degrees
Suppose and are subsets of Baire space ωω. Then is Wadge reducible to or ≤W if there is a continuous function on ωω with . The Wadge order is the preorder or quasiorder on the subsets of Baire space. Equivalence classes of sets under this preorder are called Wadge degrees, the degree of a set is denoted by []W. The set of Wadge degrees ordered by the Wadge order is called the Wadge hierarchy.
Properties of Wadge degrees include their consistency with measures of complexity stated in terms of definability. For example, if ≤W and is a countable intersection of open sets, then so is . The same works for all levels of the Borel hierarchy and the difference hierarchy. The Wadge hierarchy plays an important role in models of the axiom of determinacy. Further interest in Wadge degrees comes from computer science, where some papers have suggested Wadge degrees are relevant to algorithmic complexity.
Wadge's lemma states that under the axiom of determinacy (AD), for any two subsets of Baire space, ≤W or ≤W ωω\. The assertion that the Wadge lemma holds for sets in Γ is the semilinear ordering principle for Γ or SLO(Γ). Any defines a linear order on the equivalence classes modulo complements. Wadge's lemma can be applied locally to any pointclass Γ, for example the Borel sets, Δ1n sets, Σ1n sets, or Π1n sets. It follows from determinacy of differences of sets in Γ. Since Borel determinacy is proved in ZFC, ZFC implies Wadge's lemma for Borel sets.
Wadge's lemma is similar to the cone lemma from computability theory.
Wadge's lemma via Wadge and Lipschitz games
The Wadge game is a simple infinite game discovered by William Wadge (pronounced "wage"). It is used to investigate the notion of co |
https://en.wikipedia.org/wiki/Posterior%20auricular%20vein | The posterior auricular vein is a vein of the head. It begins from a plexus with the occipital vein and the superficial temporal vein, descends behind the auricle, and drains into the external jugular vein.
Structure
The posterior auricular vein begins upon the side of the head, in a plexus which communicates with the tributaries of the occipital vein and the superficial temporal vein. It descends behind the auricle. It joins the posterior division of the retromandibular vein. It drains into the external jugular vein.
It receive the stylomastoid vein, and some tributaries from the cranial surface of the auricle.
Variation
The posterior auricular vein may drain into the internal jugular vein or a posterior jugular vein if there are variations in the external jugular vein.
Clinical significance
Skin from the auriculomastoid region of the head may be grafted as a flap, keeping the posterior auricular vein with it. |
https://en.wikipedia.org/wiki/PhyCV | PhyCV is the first computer vision library which utilizes algorithms directly derived from the equations of physics governing physical phenomena. The algorithms appearing in the first release emulate the propagation of light through a physical medium with natural and engineered diffractive properties followed by coherent detection. Unlike traditional algorithms that are a sequence of hand-crafted empirical rules, physics-inspired algorithms leverage physical laws of nature as blueprints. In addition, these algorithms can, in principle, be implemented in real physical devices for fast and efficient computation in the form of analog computing. Currently PhyCV has three algorithms, Phase-Stretch Transform (PST) and Phase-Stretch Adaptive Gradient-Field Extractor (PAGE), and Vision Enhancement via Virtual diffraction and coherent Detection (VEViD). All algorithms have CPU and GPU versions. PhyCV is now available on GitHub and can be installed from pip.
History
Algorithms in PhyCV are inspired by the physics of the photonic time stretch (a hardware technique for ultrafast and single-shot data acquisition). PST is an edge detection algorithm that was open-sourced in 2016 and has 800+ stars and 200+ forks on GitHub. PAGE is a directional edge detection algorithm that was open-sourced in February, 2022. PhyCV was originally developed and open-sourced by Jalali-Lab @ UCLA in May 2022. In the initial release of PhyCV, the original open-sourced code of PST and PAGE is significantly refactored and improved to be modular, more efficient, GPU-accelerated and object-oriented. VEViD is a low-light and color enhancement algorithm that was added to PhyCV in November 2022.
Background
Phase-Stretch Transform (PST)
Phase-Stretch Transform (PST) is a computationally efficient edge and texture detection algorithm with exceptional performance in visually impaired images. The algorithm transforms the image by emulating propagation of light through a device with engineered diffractive |
https://en.wikipedia.org/wiki/Neutral%20particle | In physics, a neutral particle is a particle without an electric charge, such as a neutron.
The term neutral particles should not be confused with truly neutral particles, the subclass of neutral particles that are also identical to their own antiparticles.
Stable or long-lived neutral particles
Long-lived neutral particles provide a challenge in the construction of particle detectors, because they do not interact electromagnetically, except possibly through their magnetic moments. This means that they do not leave tracks of ionized particles or curve in magnetic fields. Examples of such particles include photons, neutrons, and neutrinos.
Other neutral particles
Other neutral particles are very short-lived and decay before they could be detected even if they were charged. They have been observed only indirectly. They include:
Z bosons
Dozens of heavy neutral hadrons:
Neutral mesons such as the and
The neutral Delta baryon (), and other neutral baryons, such as the and
See also
Neutral particle oscillation
Truly neutral particle |
https://en.wikipedia.org/wiki/International%20Society%20for%20Applied%20Ethology | The International Society for Applied Ethology is the leading non-profit professional organization for academics and scientists interested in the behaviour and welfare of confined or domesticated animals, including companion, farm, laboratory and zoo animal species.
The Society was created in Edinburgh in 1966, as the Society for Veterinary Ethology (SVE). It rapidly expanded to cover all applied aspects of Ethology and other Behavioural Sciences, which are relevant to many human-animal interactions, such as farming, wildlife management, the keeping of companion and laboratory animals, and the control of pests. The Society also quickly became increasingly international: it now has a federal, international structure as well as regional representatives around the world. In 1991, on the 25th anniversary of the SVE, the society was renamed the International Society for Applied Ethology (ISAE). At the International Congress that year a paper was presented by Carol Petherick and Ian Duncan entitled "The Society for Veterinary Ethology 1966-1991 the 25th Anniversary Review".
Administration of the Society is the responsibility of a Council. The council also provides technical evidence on topics relating to animal behaviour and animal welfare during the committee stages of government legislation, for example, by discussion with groups such as the UK's Farm Animal Welfare Council. The European Parliament and the Council of Europe also consult council on such matters.
The membership is drawn from all areas of the world and is divided into 11 regions based on geography. ISAE encourages academic activity within the regions, including support of regional meetings, and also holds an annual Congress based, in alternate years, in Europe and elsewhere in the world. The 50th Anniversary Congress was held back in Edinburgh in July 2016 and commemorated with the publication of the book "Animals and Us: 50 Years and More of Applied Ethology."
ISAE's official scientific journal is App |
https://en.wikipedia.org/wiki/Lieb%27s%20square%20ice%20constant | Lieb's square ice constant is a mathematical constant used in the field of combinatorics to quantify the number of Eulerian orientations of grid graphs. It was introduced by Elliott H. Lieb in 1967.
Definition
An n × n grid graph (with periodic boundary conditions and n ≥ 2) has n2 vertices and 2n2 edges; it is 4-regular, meaning that each vertex has exactly four neighbors. An orientation of this graph is an assignment of a direction to each edge; it is an Eulerian orientation if it gives each vertex exactly two incoming edges and exactly two outgoing edges.
Denote the number of Eulerian orientations of this graph by f(n). Then
is Lieb's square ice constant. Lieb used a transfer-matrix method to compute this exactly.
The function f(n) also counts the number of 3-colorings of grid graphs, the number of nowhere-zero 3-flows in 4-regular graphs, and the number of local flat foldings of the Miura fold. Some historical and physical background can be found in the article Ice-type model.
See also
Spin ice
Ice-type model |
https://en.wikipedia.org/wiki/Knowledge%20graph%20embedding | In representation learning, knowledge graph embedding (KGE), also referred to as knowledge representation learning (KRL), or multi-relation learning, is a machine learning task of learning a low-dimensional representation of a knowledge graph's entities and relations while preserving their semantic meaning. Leveraging their embedded representation, knowledge graphs (KGs) can be used for various applications such as link prediction, triple classification, entity recognition, clustering, and relation extraction.
Definition
A knowledge graph is a collection of entities , relations , and facts . A fact is a triple that denotes a link between the head and the tail of the triple. Another notation that is often used in the literature to represent a triple (or fact) is . This notation is called resource description framework (RDF). A knowledge graph represents the knowledge related to a specific domain; leveraging this structured representation, it is possible to infer a piece of new knowledge from it after some refinement steps. However, nowadays, people have to deal with the sparsity of data and the computational inefficiency to use them in a real-world application.
The embedding of a knowledge graph translates each entity and relation of a knowledge graph, into a vector of a given dimension , called embedding dimension. In the general case, we can have different embedding dimensions for the entities and the relations . The collection of embedding vectors for all the entities and relations in the knowledge graph can then be used for downstream tasks.
A knowledge graph embedding is characterized by four different aspects:
Representation space: The low-dimensional space in which the entities and relations are represented.
Scoring function: A measure of the goodness of a triple embedded representation.
Encoding models: The modality in which the embedded representation of the entities and relations interact with each other.
Additional information: Any addition |
https://en.wikipedia.org/wiki/Sibling%20rivalry%20%28animals%29 | Animals, including siblings, compete for resources such as food, territory, and potential mating partners. In animal sibling rivalry, individuals compete for parental care or limited resources, which can sometimes result in siblicide, the killing of siblings. Sibling rivalry occurs in many different forms. Siblings may compete for resources in a prenatal and/or post-birth environment. The degree of rivalry varies, ranging from a low level of violence in non-aggressive to the killing of kin in siblicide.
Function of behavior
When there are multiple offspring in a single brood, the potential for sibling rivalry arises due to competition for food and parental attention. Natural selection may favor behaviors that allow an individual offspring to gain more resources, even if the behavior decreases a sibling's fitness. Competition for food and resources can be seen in many bird species. For example, blue-footed booby (Sula nebouxii) siblings often exhibit aggression towards each other, with older chicks pecking at younger chicks. This behavior increases when there are food shortages, indicating more intense competition. In other bird species, siblings compete for food through manipulation of parental behavior rather than direct aggressive acts. Increased parental attention may mean more food for the offspring, favoring the development of begging behavior in nestlings. American robin (Turdus migratorius) chicks compete for food provided by their parents through louder and more prominent cheeps or other vocalizations, with the most food given to chicks exhibiting the most intense begging behavior.
Sibling rivalry may not seem to align with the kin selection theory, which predicts that altruistic behaviors may evolve if inclusive fitness benefits (including those of relatives) from such behaviors outweigh the costs. Theoretically, helping relatives would allow individuals to spread genes related to their own. However, some species may show sibling rivalry when the fitn |
https://en.wikipedia.org/wiki/CorDECT | corDECT is a wireless local loop standard developed in India by IIT Madras and Midas Communications (www.midascomms.com) at Chennai, under leadership of Prof Ashok Jhunjhunwala, based on the DECT digital cordless phone standard.
Overview
The technology is a Fixed Wireless Option, which has extremely low capital costs and is ideal for small start ups to scale, as well as for sparse rural areas. It is very suitable for ICT4D projects and India has one such organization, n-Logue Communications that has aptly done this.
The full form of DECT is Digital Enhanced Cordless Telecommunications, which is useful in designing small capacity WLL (wireless in local loop) systems. These systems are operative only on LOS Conditions and are very much affected by weather conditions.
System is designed for rural and sub urban areas where subscriber density is medium or low. "corDECT" system provides simultaneous voice and Internet access.
Following are the main parts of the system.
DECT Interface Unit (DIU)
This is a 1000 line exchange provides E1 interface to the PSTN. This can cater up to 20 base stations. These base stations are interfaced through ISDN link which carries signals and power feed for the base stations even up to 3 km.
Compact Base Station (CBS)
This is the radio fixed part of the DECT wireless local loop. CBSs are typically mounted on a tower top which can cater up to 50 subscribers with 0.1 erlang traffic.
Base Station Distributor (BSD)
This is a traffic aggregator used to extend the range of the wireless local-loop where 4 CBS can be connected to this.
Relay Base Station (RBS)
This another technique used to extend the range of the corDECT wireless local loop up to 25 km by a radio chain.
Fixed Remote Station (FRS)
This is the subscriber-end equipment used the corDECT wireless local loop which provides standard telephone instrument and Internet access up to 70kbit/s through Ethernet port.
The new generation corDECT technology is called Broadband |
https://en.wikipedia.org/wiki/Obelus | An obelus (plural: obeluses or obeli) is a term in codicology and latterly in typography that refers to a historical annotation mark which has resolved to three modern meanings:
Division sign
Dagger
Commercial minus sign (limited geographical area of use)
The word "obelus" comes from (obelós), the Ancient Greek word for a sharpened stick, spit, or pointed pillar. This is the same root as that of the word 'obelisk'.
In mathematics, the first symbol is mainly used in Anglophone countries to represent the mathematical operation of division and is called an obelus. In editing texts, the second symbol, also called a dagger mark , is used to indicate erroneous or dubious content; or as a reference mark or footnote indicator. It also has other uses in a variety of specialist contexts.
Use in text annotation
The modern dagger symbol originated from a variant of the obelus, originally depicted by a plain line , or a line with one or two dots . It represented an iron roasting spit, a dart, or the sharp end of a javelin, symbolizing the skewering or cutting out of dubious matter.
Originally, one of these marks (or a plain line) was used in ancient manuscripts to mark passages that were suspected of being corrupted or spurious; the practice of adding such marginal notes became known as obelism. The dagger symbol , also called an obelisk, is derived from the obelus, and continues to be used for this purpose.
The obelus is believed to have been invented by the Homeric scholar Zenodotus, as one of a system of editorial symbols. They marked questionable or corrupt words or passages in manuscripts of the Homeric epics. The system was further refined by his student Aristophanes of Byzantium, who first introduced the asterisk and used a symbol resembling a for an obelus; and finally by Aristophanes' student, in turn, Aristarchus, from whom they earned the name of "Aristarchian symbols".
In some commercial and financial documents, especially in Germany and Scandinavi |
https://en.wikipedia.org/wiki/Wildlife%20photo-identification | Photo-identification is a technique used to identify and track individuals of a wild animal study population over time. It relies on capturing photographs of distinctive characteristics such as skin or pelage patterns or scars from the animal. In cetaceans, the dorsal fin area and tail flukes are commonly used.
Photo-identification is generally used as an alternative to other, invasive methods of tagging that require attaching a device to each individual. The technique enables precise counting, rather than rough estimation, of the number of animals in a population. It also allows researchers to perform longitudinal studies of individuals over many years, yielding data about the lifecycle, lifespan, migration patterns, and social relationships of the animals.
Species that are studied using photo-identification techniques include:
Killer whales
Humpback whales
Whale sharks
Manta rays - see Manta Matcher
Octopuses (Wunderpus photogenicus)
Salamanders
Giraffes
See also
Michael Bigg, who pioneered the photo-identification of killer whales |
https://en.wikipedia.org/wiki/Quadratic%20formula | In elementary algebra, the quadratic formula is a formula that provides the two solutions, or roots, to a quadratic equation. There are other ways of solving a quadratic equation instead of using the quadratic formula, such as completing the square.
Given a general quadratic equation of the form
with representing an unknown, with , and representing constants, and with , the quadratic formula is:
where the plus–minus symbol "±" indicates that the quadratic equation has two solutions. Written separately, they become:
Each of these two solutions is also called a root (or zero) of the quadratic equation. Geometrically, these roots represent the -values at which any parabola, explicitly given as , crosses the -axis.
As well as being a formula that yields the zeros of any parabola, the quadratic formula can also be used to identify the axis of symmetry of the parabola, and the number of real zeros the quadratic equation contains.
The expression is known as the discriminant. If , , and are real numbers and then
When , there are two distinct real roots or solutions to the equation .
When , there is one repeated real solution.
When , there are two distinct complex solutions, which are complex conjugates of each other.
Equivalent formulations
The quadratic formula may also be written as
or
Because these formulas allow re-use of intermediately calculated values, these may be easier to use when computing with a calculator or by hand. When the discriminant is negative, complex roots are involved and the quadratic formula can be written as:
Muller's method
A lesser known quadratic formula, also named "citardauq", which is used in Muller's method and which can be found from Vieta's formulas, provides (assuming ) the same roots via the equation:
For positive , the subtraction causes cancellation in the standard formula (respectively negative and addition), resulting in poor accuracy. In this case, switching to Muller's formula with the opposite sign is a good |
https://en.wikipedia.org/wiki/Dragon%20protocol | The Dragon Protocol is an update based cache coherence protocol used in multi-processor systems. Write propagation is performed by directly updating all the cached values across multiple processors. Update based protocols such as the Dragon protocol perform efficiently when a write to a cache block is followed by several reads made by other processors, since the updated cache block is readily available across caches associated with all the processors.
States
Each cache block resides in one of the four states: exclusive-clean, shared-clean, shared-modified and modify.
Exclusive-clean (E): This means that the cache block was first fetched by the current processor and has not been accessed by any other processor since.
Shared clean (Sc): This means that the cache block definitely exists in multiple processor’s caches, and that the current processor is not the last one to write the block. States E and Sc are maintained separately by the protocol to prevent read-write operations on cache blocks that are not shared, from inducing bus transactions, and hence slowing down the execution. This is a common occurrence in single threaded programs.
Shared modified (Sm): This means that the block exists in caches of multiple processors, and the current processor is the last one to modify the block. Consequently, the current processor is called the owner of the block. Unlike the invalidation protocols, the block doesn’t need to be up to date in the main memory, but only in the processor. It is the processor’s responsibility to update the main memory when the cache block is evicted.
Modify (M): This means that only one processor has the memory block, and also that it has modified the value since it has been brought in from the memory.
For any given pair of caches, the permitted states of a given cache block in conjunction with the states of the other cache's states, are as follows (the states abbreviated in the order above):
Transactions
There are 4 processor transactions an |
https://en.wikipedia.org/wiki/Antecedent%20variable | In statistics and social sciences, an antecedent variable is a variable that can help to explain the apparent relationship (or part of the relationship) between other variables that are nominally in a cause and effect relationship. In a regression analysis, an antecedent variable would be one that influences both the independent variable and the dependent variable.
See also
Path analysis (statistics)
Latent variable
Intervening variable
Confounding variable |
https://en.wikipedia.org/wiki/Semiconductor%20Bloch%20equations | The semiconductor Bloch equations (abbreviated as SBEs) describe the optical response of semiconductors excited by coherent classical light sources, such as lasers. They are based on a full quantum theory, and form a closed set of integro-differential equations for the quantum dynamics of microscopic polarization and charge carrier distribution. The SBEs are named after the structural analogy to the optical Bloch equations that describe the excitation dynamics in a two-level atom interacting with a classical electromagnetic field. As the major complication beyond the atomic approach, the SBEs must address the many-body interactions resulting from Coulomb force among charges and the coupling among lattice vibrations and electrons.
Background
The optical response of a semiconductor follows if one can determine its macroscopic polarization as a function of the electric field that excites it. The connection between and the microscopic polarization is given by
where the sum involves crystal-momenta of all relevant electronic states. In semiconductor optics, one typically excites transitions between a valence and a conduction band. In this connection, is the dipole matrix element between the conduction and valence band and defines the corresponding transition amplitude.
The derivation of the SBEs starts from a system Hamiltonian that fully includes the free-particles, Coulomb interaction, dipole interaction between classical light and electronic states, as well as the phonon contributions. Like almost always in many-body physics, it is most convenient to apply the second-quantization formalism after the appropriate system Hamiltonian is identified. One can then derive the quantum dynamics of relevant observables by using the Heisenberg equation of motion
Due to the many-body interactions within , the dynamics of the observable couples to new observables and the equation structure cannot be closed. This is the well-known BBGKY hierarchy problem that can |
https://en.wikipedia.org/wiki/Social%20software%20%28research%20field%29 | In philosophy and the social sciences, social software is an interdisciplinary research program that borrows
mathematical tools and techniques from game theory and computer science in order to analyze and design social procedures. The goals of research in this field are modeling social situations, developing theories of correctness, and designing social procedures.
Work under the term social software has been going on since about 1996, and conferences in Copenhagen, London, Utrecht and New York, have been partly or wholly devoted to it. Much of the work is carried out at the City University of New York under the leadership of Rohit Jivanlal Parikh, who was influential in the development of the field.
Goals and tools
Current research in the area of social software include the analysis of social procedures and examination of them for fairness, appropriateness, correctness and efficiency. For example, an election procedure could be a simple majority vote, Borda count, a Single Transferable vote (STV), or Approval voting. All of these procedures can be examined for various properties like monotonicity. Monotonicity has the property that voting for a candidate should not harm that candidate. This may seem obvious, true
under any system, but it is something which can happen in STV. Another question would be the ability to elect a Condorcet winner in case there is one.
Other principles which are considered by researchers in social software include the concept that a procedure for fair division should be Pareto optimal, equitable and envy free. A procedure for auctions should be one which would encourage bidders to bid their actual valuation – a property which holds with the Vickrey auction.
What is new in social software compared to older fields is the use of tools from computer science like program logic, analysis of algorithms and epistemic logic. Like programs, social procedures dovetail into each other. For instance an airport provides runways for planes to l |
https://en.wikipedia.org/wiki/Facebook%20content%20management%20controversies | Facebook or Meta Platforms has been criticized for its management of various content on posts, photos and entire groups and profiles. This includes but is not limited to allowing violent content, including content related to war crimes, and not limiting the spread of fake news and COVID-19 misinformation on their platform, as well as allowing incitement of violence against multiple groups.
Intellectual property infringement
Facebook has been criticized for having lax enforcement of third-party copyrights for videos uploaded to the service. In 2015, some Facebook pages were accused of plagiarizing videos from YouTube users and re-posting them as their own content using Facebook's video platform, and in some cases, achieving higher levels of engagement and views than the original YouTube posts. Videos hosted by Facebook are given a higher priority and prominence within the platform and its user experience (including direct embedding within the News Feed and pages), giving a disadvantage to posting it as a link to the original external source. In August 2015, Facebook announced a video-matching technology aiming to identify reposted videos, and also stated its intention to improve its procedures to remove infringing content faster. In April 2016, Facebook implemented a feature known as "Rights Manager", which allows rights holders to manage and restrict the upload of their content onto the service by third-parties.
Violent content
In 2013, Facebook was criticized for allowing users to upload and share videos depicting violent content, including clips of people being decapitated. Having previously refused to delete such clips under the guideline that users have the right to depict the "world in which we live", Facebook changed its stance in May, announcing that it would remove reported videos while evaluating its policy. The following October, Facebook stated that it would allow graphic videos on the platform, as long as the intention of the video was to "condemn, n |
https://en.wikipedia.org/wiki/Online%20help | Online help is topic-oriented, procedural or reference information delivered through computer software. It is a form of user assistance. The purpose of most online help is to assist in using a software application, web application or operating system. However, it can also present information on a broad range of subjects. Online help linked to the application's state (what the user is doing) is called Context-sensitive help.
Benefits
Online help has largely replaced live customer support. Before its availability, support could only be given through printed documentation, postal mail, or telephone.
Platforms
Online help is created using help authoring tools or component content management systems. It is delivered in a wide variety of formats, some proprietary and some open-standard, including:
Hypertext Markup Language (HTML), which includes HTML Help, HTML-based Help, JavaHelp, and Oracle Help
Adobe Portable Document Format (PDF)
Online help is also provided via live chat systems, one step removed from telephone calls. This allows the support person to conduct several support sessions simultaneously, thus reducing costs. The transcript is immediately available and can be sent to the customer after the session ends.
The chat feature also reduces the intense negativity that can be directed at customer support personnel, requiring the customer to calm down and articulate their thoughts more clearly.
DITA and DocBook
The Open Source tool DocBook XSL can also generate help files and is a resource for single source publishing. From one source, DocBook can generate PDF, JavaHelp, WebHelp, eBook and many more formats (even .chm files if required). The same with DITA, which is even favored for that purpose.
Microsoft help platforms
Microsoft develops the platforms for delivering help systems in the Microsoft Windows operating system.
Other platforms
See also
Balloon help
Darwin Information Typing Architecture
DocBook
Frequently Asked Questions
List of help authoring |
https://en.wikipedia.org/wiki/Gaussian%20gravitational%20constant | The Gaussian gravitational constant (symbol ) is a parameter used in the orbital mechanics of the Solar System.
It relates the orbital period to the orbit's semi-major axis and the mass of the orbiting body in Solar masses.
The value of historically expresses the mean angular velocity of the system of Earth+Moon and the Sun considered as a two body problem,
with a value of about 0.986 degrees per day, or about 0.0172 radians per day. As a consequence of the law of gravitation and Kepler's third law,
is directly proportional to the square root of the standard gravitational parameter of the Sun, and its value in radians per day follows by setting Earth's semi-major axis (the astronomical unit, au) to unity, :(rad/d) ()0.5·au−1.5.
A value of rad/day was determined by Carl Friedrich Gauss in his 1809 work Theoria Motus Corporum Coelestium in Sectionibus Conicis Solem Ambientum ("Theory of the Motion of the Heavenly Bodies Moving about the Sun in Conic Sections").
Gauss' value was introduced as a fixed, defined value by the IAU (adopted in 1938, formally defined in 1964), which detached it from its immediate representation of the (observable) mean angular velocity of the Sun–Earth system. Instead, the astronomical unit now became a measurable quantity slightly different from unity. This was useful in 20th-century celestial mechanics to prevent the constant adaptation of orbital parameters to updated measured values, but it came at the expense of intuitiveness, as the astronomical unit, ostensibly a unit of length, was now dependent on the measurement of the strength of the gravitational force.
The IAU abandoned the defined value of in 2012 in favour of a defined value of the astronomical unit of exactly, while the strength of the gravitational force is now to be expressed in the separate standard gravitational parameter , measured in SI units of m3⋅s−2.
Discussion
Gauss' constant is derived from the application of Kepler's third law to the
system of Ea |
https://en.wikipedia.org/wiki/Medial%20axis | The medial axis of an object is the set of all points having more than one closest point on the object's boundary. Originally referred to as the topological skeleton, it was introduced in 1967 by Harry Blum as a tool for biological shape recognition. In mathematics the closure of the medial axis is known as the cut locus.
In 2D, the medial axis of a subset S which is bounded by planar curve C is the locus of the centers of circles that are tangent to curve C in two or more points, where all such circles are contained in S. (It follows that the medial axis itself is contained in S.)
The medial axis of a simple polygon is a tree whose leaves are the vertices of the
polygon, and whose edges are either straight segments or arcs of parabolas.
The medial axis together with the associated radius function of the maximally inscribed discs is called the medial axis transform (MAT). The medial axis transform is a complete shape descriptor (see also shape analysis), meaning that it can be used to reconstruct the shape of the original domain.
The medial axis is a subset of the symmetry set, which is defined similarly, except that it also includes circles not contained in S. (Hence, the symmetry set of S generally extends to infinity, similar to the Voronoi diagram of a point set.)
The medial axis generalizes to k-dimensional hypersurfaces by replacing 2D circles with k-dimension hyperspheres. The 2D medial axis is useful for character and object recognition, while the 3D medial axis has applications in surface reconstruction for physical models, and for dimensional reduction of complex models. In any dimension, the medial axis of a bounded open set is homotopy equivalent to the given set.
If S is given by a unit speed parametrisation , and is the unit tangent vector at each point. Then there will be a bitangent circle with center c and radius r if
For most curves, the symmetry set will form a one-dimensional curve and can contain cusps. The symmetry set has end points |
https://en.wikipedia.org/wiki/Erkenntnis | Erkenntnis is a journal of philosophy that publishes papers in analytic philosophy. Its name is derived from the German word "Erkenntnis", meaning "knowledge, recognition". The journal was also linked to organisation of conferences, such as the Second Conference on the Epistemology of the Exact Sciences, of which it published the papers and accounts of the discussions.
First series (1930–1940)
When Hans Reichenbach and Rudolf Carnap took charge of Annalen der Philosophie und philosophischen Kritik in 1930 they renamed it Erkenntnis, under which name it was published 1930–1938. The journal was published by the Gesellschaft für Empirische Philosophie, or the Berlin Circle and the Verein Ernst Mach, Vienna. In the first issue Reichenbach noted that the editors hoped to gain a better understanding of the nature of all human knowledge through consideration of the procedures and results of a variety of scientific disciplines, whilst also hoping that philosophy need not remain a series of "systems" but could reach the state of being objective knowledge. The final issue of the first series, Volume 8, No. 1 was published in 1939 and retitled The Journal of Unified Science (Erkenntnis) (1939–1940) and included as associate editors Philipp Frank, Jørgen Jørgensen (:da:Jørgen Jørgensen_filosof), Charles W. Morris, Otto Neurath, and Louis Rougier. The advent of World War II led to the cessation of publication.
Second series (1975–present)
In 1975 the journal was "refounded" by Wilhelm K. Essler, Carl G. Hempel and Wolfgang Stegmüller, and it has been published continuously ever since. The journal's current editor-in-chief is Hannes Leitgeb (Ludwig Maximilian University of Munich), and the supervisory board is composed of Michael Friedman (Stanford University), Hans Rott (University of Regensburg), and Wolfgang Spohn (Konstanz University).
See also
List of philosophy journals |
https://en.wikipedia.org/wiki/Anchovy%20essence | Anchovy essence is a brown or pink, thick, oily sauce, consisting of pounded anchovies, spices such as black pepper or cayenne pepper, and sometimes wine. It is used as a flavoring for soups, sauces, and other dishes since at least the 19th century. It has been called a British equivalent of Asian fish sauce.
See also |
https://en.wikipedia.org/wiki/TradeCard | TradeCard, Inc. was an American software company. Its main product, also called TradeCard, was a SaaS collaboration product that was designed to allow companies to manage their extended supply chains including tracking movement of goods and payments. TradeCard software helped to improve visibility, cash flow and margins for over 10,000 retailers and brands, factories and suppliers, and service providers (financial institutions, logistics service providers, customs brokers and agents) operating in 78 countries.
On January 7, 2013, TradeCard and GT Nexus announced plans to undergo a merger of equals, creating a global supply-chain management company that would employ about 1,000 people and serve about 20,000 businesses in industries including manufacturing, retail and pharmaceuticals. The combined company rebranded itself as GT Nexus.
History
TradeCard was founded in 1999 by Kurt Cavano as a privately owned firm.
In 2003, Warburg Pincus led three funding rounds, with TradeCard closing $10 million.
In 2010, Deloitte cited TradeCard for its entrepreneurial and disruptive cloud technology enterprise resource planning solution that provides new IT architectures designed to address unmet needs of enterprises.
In 2011, TradeCard's revenue grew by 36% over the previous year, and the company claimed on its website that it handled $25 billion in sourcing volume on its platform, by 10,000 organizations and 45,000 unique users. In 2012, founder and CEO Kurt Cavano transitioned to the Chairman role and Sean Feeney was appointed CEO.
TradeCard was headquartered in New York City, with offices in San Francisco, Amsterdam, Hong Kong, Shenzhen, Shanghai, Taipei, Seoul, Colombo and Ho Chi Minh City.
Clients
TradeCard provided global supply chain and financial supply chain products to retail companies, factories and suppliers, and service providers (financial institutions, logistics service providers, customs brokers and agents).
Clients include retailers and brands such as Coa |
https://en.wikipedia.org/wiki/Frubber | Frubber (from "flesh rubber") is a patented elastic form of rubber used in robotics. The spongy elastomer has been used by Hanson Robotics for the face of its android robots, including Einstein 3 and Sophia. |
https://en.wikipedia.org/wiki/Motorized%20potentiometer | A motorized potentiometer combines a potentiometer with an electric motor.
Uses
Motorized potentiometers can be found in audio/video equipment, specifically mixing consoles. In this application, they are called motorized faders. Mixing consoles with motorized faders typically implement the possibility to save and restore settings on the same console and sometimes to transfer settings to a different console. Save and restore also allows to control more channels then there are sliders by switching which tracks are controlled. While historically, the faders where literal motorized potentiometers, nowadays faders may directly digitize the fader position and apply the value digitally in the digital signal processing.
Motorized potentiometers are used in industrial controls.
Motorized potentiometers may be used for remote control applications.
Motorized potentiometers can be used to build electrical/electronic analog computers. The motorized potentiometer can act as a computing element, but also as a way to convert a physical into an electrical value.
Servo (radio control) are motors that use a potentiometer as feedback for the servo position.
Features
Some motorized potentiometers allow both manual and motorized operation.
Motorized potentiometers can be slide or rotary potentiometers. There also exist multiple turn motorized potentiometers.
The end of travel may be detected using limit switches, a peak in motor current as the mechanism stalls, or a separate resistive element used for position feedback.
History
Given that the history of the motorized potentiometer is linked to electronic analog computers, and electronic analog computers to military use, recording keeping and publication were limited, also meaning that parallel invention was highly likely. The M9 Gun Director had a potentiometer controlled by op amps. The Bomben-Abwurfrechner BT-9 has a motor driven potentiometer to convert a pressure into a potentiometer setting.
In 1968 a patent was fil |
https://en.wikipedia.org/wiki/Naemon | Naemon is an open-source computer system monitoring, network monitoring and infrastructure monitoring software application. Naemon offers monitoring and alerting services for servers, switches, applications, and services. It alerts the users when things go wrong and alerts them a second time when the problem has been resolved. Naemon was created in 2014 as a fork of Nagios.
It is available for Red Hat, CentOS, SUSE, Debian and Ubuntu Linux distribution.
Overview
Naemon is open source software licensed under the GNU GPL V2. It provides:
Monitoring of network services (SMTP, POP3, HTTP, NNTP, PING, etc.).
Monitoring of host resources (processor load, disk usage, etc.).
A simple plugin design that allows users to easily develop their own service checks.
Parallelized service checks.
Thruk Monitoring Webinterface.
The ability to define network host hierarchies using 'parent' hosts, allowing the detection of and distinction between hosts that are down or unreachable.
Contact notifications when service or host problems occur and get resolved (via e-mail, pager, or any user-defined method through plugin system).
The ability to define event handlers to be run during service or host events for proactive problem resolution
Automatic log file rotation
Support for implementing redundant monitoring hosts
See also
Comparison of network monitoring systems
Nagios
Icinga – Another Nagios fork
Shinken (software) – Another Nagios fork |
https://en.wikipedia.org/wiki/Ranorex%20Studio | Ranorex Studio is a GUI test automation framework provided by Ranorex GmbH, a software development company. The framework is used for the testing of desktop, web-based and mobile applications.
Overview
Ranorex Studio supports development of automated test modules using standard programming languages such as C# and VB.NET.
Main features
GUI object recognition, filtering GUI elements using the company's proprietary technology RanoreXPath.
Object-based record and replay, using Ranorex Recorder, which records the user's interaction with a desktop or web-based application and creates user-maintainable scripts that can be edited with the Ranorex Studio action editor. The recorded actions are available as both C# and VB.NET code. Record and replay is supported on mobile devices for actions such as key presses and touch gestures.
Supported technologies
Windows desktop client applications such as .NET, WPF, Win32, VB6, Java, MFC, Embarcadero Delphi.
Web technologies such as HTML, HTML5, JavaScript Frameworks, Ajax, Silverlight, Flash, and Flex.
Cross-browser testing for Chrome, Safari, Microsoft Edge, Internet Explorer, and Firefox
Mobile Apps
native iOS apps
native Android apps
System environment
Ranorex Studio runs on Microsoft Windows and Windows Server. As of version 10.2, Ranorex Studio supports Windows 11
Reception
In a 2018 review by Forrester Research of 15 omnichannel functional test automation tools including Ranorex Studio 8.1.1, Ranorex was ranked as having the weakest current offering and the second-weakest strategy, scoring 1.65 of 5 and 1.5 of 5 respectively.
In 2019, Ranorex was one of 10 vendors evaluated in the Gartner Magic Quadrant for Software Test Automation. Gartner identified Ranorex as a "niche player".
See also
Test automation
GUI software testing
Web testing
List of web testing tools
List of GUI testing tools |
https://en.wikipedia.org/wiki/Silvicide |
As herbicides are pesticides used to kill unwanted plants, silvicides are special pesticides (cacodylic acid or MSMA for instance) used to kill brush and trees, or "entire forest" or unwanted forest species.
See also
Bioherbicide
Deforestation
List of environmental health hazards
Soil contamination
Surface runoff |
https://en.wikipedia.org/wiki/WEMO | WEMO, a subsidiary of Belkin, are a series of products from Belkin that enable users to control home electronics remotely. The product suite includes electrical plugs, motion sensors, light switches, cameras, light bulbs, and a mobile app.
Products
The Wemo Switch can be plugged into any home outlet, which can then be controlled from an iOS or Android smartphone running the Wemo App, via home Wi-Fi or mobile phone network.
The Wemo Motion Sensor can be placed anywhere, as long as it can access the same Wi-Fi network as the Wemo devices it is intended to control. It can then turn on and off any of the Wemo devices connected to the Wi‑Fi network as people pass by.
The Wemo Insight Switch provides information on power usage and cost estimation for devices plugged into the switch.
The Wemo Light Switch is for use where a light is controlled by a single light switch. Multi-way switching is not supported at this time but can be approximated by installing a Wemo Light Switch at each location.
The Wemo App controls the Wemo devices from anywhere in the world as long as the Wemo devices' wireless network is connected to the Internet. Wemo devices can also be controlled using IFTTT technology. Wemo devices can also be controlled by voice through the Amazon Echo, Google Assistant, and Apple's Siri (through the use of the Wemo Bridge).
Remote security vulnerability
Wemo switches are controlled via IP networks; thus, for a switch to be controllable from a remote location, it must be open to receive connections from the Internet. In January 2013, it was revealed that the Wemo had a security flaw in its UPnP implementation that allowed an unauthorized user to take control of a switch. This could allow malicious attacks, such as flipping the switch at a very fast rate, which could damage certain devices and even cause electrical fires.
This vulnerability has been addressed by updated firmware releases. |
https://en.wikipedia.org/wiki/Highsnobiety | Highsnobiety is a global fashion and lifestyle media brand founded in 2005 by David Fischer. It was bought by German e-commerce giant Zalando in 2022.
Highsnobiety is headquartered in Berlin and has offices in Amsterdam, London, Milan, New York, Los Angeles and Sydney.
Highsnobiety has a digital-first publishing approach, with a multichannel presence. The print magazine first launched in 2010, with quarterly issues published globally.
Highsnobiety Shop, a multi-brand online fashion and lifestyle retailer, was launched in 2019. Highsnobiety launched their apparel collection in 2021.
Since 2018, the brand publishes regular research papers in the fields of luxury and young consumer trends in collaboration with Boston Consulting Group.
In 2021, Highsnobiety launched Gate Zero, a travel retail concept with locations in Zurich International Airport. In 2022, travel retail company Gebr. Heinemann announced a joint venture to expand the concept, beginning with a location at Copenhagen International Airport.
Awards and honors
2022 D&AD Wood Pencil Award for Advertising, Design, Craft, Culture and Impact
2022 Webby Award for Advertising, Media & PR Fashion, Beauty & Lifestyle
2022 Webby Award for Video Fashion & Lifestyle (Branded)
2018 Digiday Award for Best In-House Content/Brand Studio
2017 Webby Award for Cultural Blog/Website
2017 BoF 500, Business of Fashion |
https://en.wikipedia.org/wiki/SLFN12 | Schlafen family member 12 is a protein in humans that is encoded by the SLFN12 gene. |
https://en.wikipedia.org/wiki/Potassium%20nitrite | Potassium nitrite (distinct from potassium nitrate) is the inorganic compound with the chemical formula . It is an ionic salt of potassium ions K+ and nitrite ions NO2−, which forms a white or slightly yellow, hygroscopic crystalline powder that is soluble in water.
It is a strong oxidizer and may accelerate the combustion of other materials. Like other nitrite salts such as sodium nitrite, potassium nitrite is toxic if swallowed, and laboratory tests suggest that it may be mutagenic or teratogenic. Gloves and safety glasses are usually used when handling potassium nitrite.
Discovery
Nitrite is present at trace levels in soil, natural waters, plant and animal tissues, and fertilizer. The pure form of nitrite was first made by the Swedish chemist Carl Wilhelm Scheele working in the laboratory of his pharmacy in the market town of Köping. He heated potassium nitrate at red heat for half an hour and obtained what he recognized as a new “salt.” The two compounds (potassium nitrate and nitrite) were characterized by Péligot and the reaction was established as:
2KNO3 ->[\Delta T] 2KNO2 + O2
Production
Potassium nitrite can be obtained by the reduction of potassium nitrate. The production of potassium nitrite by absorption of nitrogen oxides in potassium hydroxide or potassium carbonate is not employed on a large scale because of the high price of these alkalies. Furthermore, the fact that potassium nitrite is highly soluble in water makes the solid difficult to recover.
Reactions
The mixing of cyanamide and KNO2 produces changes from white solids to yellow liquid and then to orange solid, forming cyanogen and ammonia gases. No external energy is used and the reactions are carried out with a small amount of O2.
Potassium nitrite forms potassium nitrate when heated in the presence of oxygen from 550 °C to 790 °C. The rate of reaction increases with temperature, but the extent of reaction decreases. At 550 °C and 600 °C the reaction is continuous and eventually goes to |
https://en.wikipedia.org/wiki/Manifold%20alignment | Manifold alignment is a class of machine learning algorithms that produce projections between sets of data, given that the original data sets lie on a common manifold. The concept was first introduced as such by Ham, Lee, and Saul in 2003, adding a manifold constraint to the general problem of correlating sets of high-dimensional vectors.
Overview
Manifold alignment assumes that disparate data sets produced by similar generating processes will share a similar underlying manifold representation. By learning projections from each original space to the shared manifold, correspondences are recovered and knowledge from one domain can be transferred to another. Most manifold alignment techniques consider only two data sets, but the concept extends to arbitrarily many initial data sets.
Consider the case of aligning two data sets, and , with and .
Manifold alignment algorithms attempt to project both and into a new d-dimensional space such that the projections both minimize distance between corresponding points and preserve the local manifold structure of the original data. The projection functions are denoted:
Let represent the binary correspondence matrix between points in and :
Let and represent pointwise similarities within data sets. This is usually encoded as the heat kernel of the adjacency matrix of a k-nearest neighbor graph.
Finally, introduce a coefficient , which can be tuned to adjust the weight of the 'preserve manifold structure' goal, versus the 'minimize corresponding point distances' goal.
With these definitions in place, the loss function for manifold alignment can be written:
Solving this optimization problem is equivalent to solving a generalized eigenvalue problem using the graph laplacian of the joint matrix, G:
Inter-data correspondences
The algorithm described above requires full pairwise correspondence information between input data sets; a supervised learning paradigm. However, this information is usually difficult or impossible |
https://en.wikipedia.org/wiki/MAP3K1 | Mitogen-activated protein kinase kinase kinase 1 (MAP3K1) is a signal transduction enzyme that in humans is encoded by the autosomal MAP3K1 gene.
Function
MAP3K1 (or MEKK1) is a serine/threonine kinase and ubiquitin ligase that performs a pivotal role in a network of enzymes integrating cellular receptor responses to a number of mitogenic and metabolic stimuli, including: TNF receptor superfamily (TNFRs), T-cell receptor (TCR), Epidermal growth factor receptor (EGFR), and TGF beta receptor (TGFβR). Mitogen-activated protein kinase kinases (MAP2Ks) are substrates for direct phosphorylation by the MAP3K1 protein kinase. The MAP3K1 kinase domain may also be a modest activator of IκB kinase activation. The MAP3K1 E3 ubiquitin ligase recruits a ubiquitin-conjugating enzyme (including UBE2D2, UBE2D3, and UBE2N:UBE2V1) that has been loaded with ubiquitin, interacts with its substrates, and facilitates the transfer of ubiquitin from the ubiquitin-conjugating enzyme onto its substrates. Genetics has revealed that MAP3K1 is important in: embryonic development, tumorigenesis, cell growth, cell migration, cytokine production, and humoral immunity. MAP3K1 mutants were identified in breast cancer by GWAS.
Structure
MAP3K1 contains a protein kinase domain, PHD finger (which has a RING finger domain-like structure) that serves as an E3 ubiquitin ligase, and scaffold protein regions that mediate protein–protein interactions.
Genetic analyses in murine and avian models
MAP3K1 is highly conserved in Euteleostomi. The spontaneous recessive lidgap-Gates mutation (deletion of Map3k1 exons 2–9, initially described in the 1960s) identified on the SELH/Bc mouse strain causes the same open-eyelids-at-birth mutational phenotype as the gene knockout mutations of the mouse (but not human) MAP3K1 homolog (Map3k1) and also co-maps to distal Chromosome 13. MAP3K1 was analysed genetically by targeted mutagenesis using transgenic mice (C57BL/6 and C57BL/6 × 129 backgrounds), embryonic ste |
https://en.wikipedia.org/wiki/Fractal%20landscape | A fractal landscape or fractal surface is generated using a stochastic algorithm designed to produce fractal behavior that mimics the appearance of natural terrain. In other words, the surface resulting from the procedure is not a deterministic, but rather a random surface that exhibits fractal behavior.
Many natural phenomena exhibit some form of statistical self-similarity that can be modeled by fractal surfaces. Moreover, variations in surface texture provide important visual cues to the orientation and slopes of surfaces, and the use of almost self-similar fractal patterns can help create natural looking visual effects.
The modeling of the Earth's rough surfaces via fractional Brownian motion was first proposed by Benoit Mandelbrot.
Because the intended result of the process is to produce a landscape, rather than a mathematical function, processes are frequently applied to such landscapes that may affect the stationarity and even the overall fractal behavior of such a surface, in the interests of producing a more convincing landscape.
According to R. R. Shearer, the generation of natural looking surfaces and landscapes was a major turning point in art history, where the distinction between geometric, computer generated images and natural, man made art became blurred. The first use of a fractal-generated landscape in a film was in 1982 for the movie Star Trek II: The Wrath of Khan. Loren Carpenter refined the techniques of Mandelbrot to create an alien landscape.
Behavior of natural landscapes
Whether or not natural landscapes behave in a generally fractal manner has been the subject of some research. Technically speaking, any surface in three-dimensional space has a topological dimension of 2, and therefore any fractal surface in three-dimensional space has a Hausdorff dimension between 2 and 3. Real landscapes however, have varying behavior at different scales. This means that an attempt to calculate the 'overall' fractal dimension of a real landscape c |
https://en.wikipedia.org/wiki/Protein%20footprinting | Protein footprinting is a term used to refer to a method of biochemical analysis that investigates protein structure, assembly, and interactions within a larger macromolecular assembly. It was originally coined in reference to the use of limited proteolysis to investigate contact sites within a monoclonal antibody - protein antigen complex and a year later to examine the protection from hydroxyl radical cleavage conferred by a protein bound to DNA within a DNA-protein complex. In DNA footprinting the protein is envisioned to make an imprint (or footprint) at a particular point of interaction. This latter method was adapted through the direct treatment of proteins and their complexes with hydroxyl radicals and can be generally denoted RP-MS (for Radical Probe - Mass Spectrometry) akin to the designation used for Hydrogen-deuterium exchange Mass Spectrometry (denoted HD-MS or HX-MS).
Hydroxyl radical protein footprinting
Time-resolved hydroxyl radical protein footprinting (HRPF) employing mass spectrometry analysis was originated and developed in the late 1990s in synchrotron radiolysis studies. The same year, these authors (Maleknia et al.) reported on the use of an electrical discharge source to effect the oxidation of proteins on millisecond timescales as proteins pass from the electrosprayed solution into the mass spectrometer.
Years later in 2005, researchers Hambly and Gross introduced a method for protein oxidation on the microsecond timescale using laser flash photolysis of hydrogen peroxide to generate hydroxyl radicals. This method, fast photochemical oxidation of proteins (FPOP), claimed to footprint proteins faster than they change their fold though this timeframe has been challenged given hydrogen peroxide, not present in the original studies, and secondary radicals, react alone in situ over tens of milliseconds. These approaches have since been used to determine protein structures, protein folding, protein dynamics, and protein–protein interactions.
U |
https://en.wikipedia.org/wiki/Chyron%20Corporation | The Chyron Corporation, formerly ChyronHego Corporation, headquartered in Melville, New York, is a company that specializes in broadcast graphics creation, playout, and real-time data visualization for live television, news, weather, and sports production. Chyron's graphics offerings include hosted services for graphics creation and order management, on-air graphics systems, channel branding, weather graphics, graphics asset management, clip servers, social media and second screen applications, touchscreen graphics, telestration, virtual graphics, and player tracking.
The company was founded in 1966 as Systems Resources Corporation. In its early days it was renamed "Chiron" after the centaur Chiron in Greek mythology. In the 1970s it pioneered the development of broadcast titling and graphics systems. Use of its graphics generators by the major New York City–based US television networks ABC, NBC, and eventually CBS, integrated text and graphics into news and sports coverage on broadcast television and later on cable TV.
By the 1980s, Chyron had captured a 70% market share in its field. In it was the most profitable company on Long Island. In 1983 it achieved a market capitalization of $112 million, high at the time for a small high-tech firm before the age of dot-com and the Internet.
Corporate history
Chyron's graphics generator technology was originated by Systems Resources Corporation, founded in 1966 by Francis Mechner and engineer Eugene Leonard as equal partners and sole directors and shareholders. Mechner had just sold his educational technology company Basic Systems, Inc. to Xerox Corporation; and Leonard had sold Digitronics Corporation, of which he was president. Mechner and Leonard previously worked together in the late 1950s at Schering Corporation, creating a computerized data collection and analysis system for its behavioral psychopharmacology laboratory.
Mechner provided the capital for Systems Resources Corporation's first five years of operatio |
https://en.wikipedia.org/wiki/Model%E2%80%93view%E2%80%93presenter | Model–view–presenter (MVP) is a derivation of the model–view–controller (MVC) architectural pattern, and is used mostly for building user interfaces.
In MVP, the presenter assumes the functionality of the "middle-man". In MVP, all presentation logic is pushed to the presenter.
History
The model–view–presenter software pattern originated in the early 1990s at Taligent, a joint venture of Apple, IBM, and Hewlett-Packard. MVP is the underlying programming model for application development in Taligent's C++-based CommonPoint environment. The pattern was later migrated by Taligent to Java and popularized in a paper by Taligent CTO Mike Potel.
After Taligent's discontinuation in 1998, Andy Bower and Blair McGlashan of Dolphin Smalltalk adapted the MVP pattern to form the basis for their Smalltalk user interface framework. In 2006, Microsoft began incorporating MVP into its documentation and examples for user interface programming in the .NET Framework.
The evolution and multiple variants of the MVP pattern, including the relationship of MVP to other design patterns such as MVC, is discussed in detail in an article by Martin Fowler and another by Derek Greer.
Overview
MVP is a user interface architectural pattern engineered to facilitate automated unit testing and improve the separation of concerns in presentation logic:
The model is an interface defining the data to be displayed or otherwise acted upon in the user interface.
The view is a passive interface that displays data (the model) and routes user commands (events) to the presenter to act upon that data.
The presenter acts upon the model and the view. It retrieves data from repositories (the model), and formats it for display in the view.
Normally, the view implementation instantiates the concrete presenter object, providing a reference to itself. The following C# code demonstrates a simple view constructor:
public class Presenter : IPresenter
{
public Presenter(IView view)
{
// ...
|
https://en.wikipedia.org/wiki/Serpentine%20geometry%20plasma%20actuator | The serpentine plasma actuator represents a broad class of plasma actuator. The actuators vary from the standard type in that their electrode geometry has been modified in to be periodic across its span.
History
This class of plasma actuators was developed at the Applied Physics Research Group (APRG) at the University of Florida in 2008 by Subrata Roy for the purpose of controlling laminar and turbulent boundary layer flows. Since then, APRG has continued to characterize and develop uses for this class of plasma actuators. Several patents resulted from the early work on serpentine geometry plasma actuators.
In 2013, these actuators started to get broader attention in the scientific press, and several articles were written about these actuators, including articles in AIP's EurekAlert, Inside Science and various blogs.
Current Research and Operating Mechanisms
Serpentine plasma actuators (like other Dielectric Barrier Discharge actuators, i.e. plasma actuators) are able to induce an atmospheric plasma and introduce an electrohydrodynamic body force to a fluid. This body force can be used to implement flow control, and there are a range of potential applications, including drag reduction for aircraft and flow stabilization in combustion chambers.
The important distinction between serpentine plasma actuators and more traditional geometries is that the geometry of the electrodes has been modified in order to be periodic across its span. As the electrode has been made periodic, the resulting plasma and body force are also spanwise periodic. With this spanwise periodicity, three-dimensional flow effects can be induced in the flow, which cannot be done with more traditional plasma actuator geometries.
It is thought that the introduction of three-dimensional flow effects allow for the plasma actuators to apply much greater levels of control authority as they allow for the plasma actuators to project onto a greater range of physical mechanisms (such as boundary layer s |
https://en.wikipedia.org/wiki/Extended%20periodic%20table | An extended periodic table theorises about chemical elements beyond those currently known in the periodic table and proven. The element with the highest atomic number known is oganesson (Z = 118), which completes the seventh period (row) in the periodic table. All elements in the eighth period and beyond thus remain purely hypothetical.
Elements beyond 118 will be placed in additional periods when discovered, laid out (as with the existing periods) to illustrate periodically recurring trends in the properties of the elements concerned. Any additional periods are expected to contain a larger number of elements than the seventh period, as they are calculated to have an additional so-called g-block, containing at least 18 elements with partially filled g-orbitals in each period. An eight-period table containing this block was suggested by Glenn T. Seaborg in 1969. The first element of the g-block may have atomic number 121, and thus would have the systematic name unbiunium. Despite many searches, no elements in this region have been synthesized or discovered in nature.
According to the orbital approximation in quantum mechanical descriptions of atomic structure, the g-block would correspond to elements with partially filled g-orbitals, but spin–orbit coupling effects reduce the validity of the orbital approximation substantially for elements of high atomic number. Seaborg's version of the extended period had the heavier elements following the pattern set by lighter elements, as it did not take into account relativistic effects. Models that take relativistic effects into account predict that the pattern will be broken. Pekka Pyykkö and Burkhard Fricke used computer modeling to calculate the positions of elements up to Z = 172, and found that several were displaced from the Madelung rule. As a result of uncertainty and variability in predictions of chemical and physical properties of elements beyond 120, there is currently no consensus on their placement in the extende |
https://en.wikipedia.org/wiki/Resonances%20in%20scattering%20from%20potentials | In quantum mechanics, resonance cross section occurs in the context of quantum scattering theory, which deals with studying the scattering of quantum particles from potentials. The scattering problem deals with the calculation of flux distribution of scattered particles/waves as a function of the potential, and of the state (characterized by conservation of momentum/energy) of the incident particle. For a free quantum particle incident on the potential, the plane wave solution to the time-independent Schrödinger wave equation is:
For one-dimensional problems, the transmission coefficient is of interest. It is defined as:
where is the probability current density. This gives the fraction of incident beam of particles that makes it through the potential. For three-dimensional problems, one would calculate the scattering cross-section , which, roughly speaking, is the total area of the incident beam which is scattered. Another quantity of relevance is the partial cross-section, , which denotes the scattering cross section for a partial wave of a definite angular momentum eigenstate. These quantities naturally depend on , the wave-vector of the incident wave, which is related to its energy by:
The values of these quantities of interest, the transmission coefficient (in case of one dimensional potentials), and the partial cross-section show peaks in their variation with the incident energy . These phenomena are called resonances.
One-dimensional case
Mathematical description
A one-dimensional finite square potential is given by
The sign of determines whether the square potential is a well or a barrier. To study the phenomena of resonance, the time-independent Schrödinger equation for a stationary state of a massive particle with energy is solved:
The wave function solutions for the three regions are
Here, and are the wave numbers in the potential-free region and within the potential respectively:
To calculate , a coefficient in the wave function is set a |
https://en.wikipedia.org/wiki/Erd%C5%91s%E2%80%93P%C3%B3sa%20theorem | In the mathematical discipline of graph theory, the Erdős–Pósa theorem, named after Paul Erdős and Lajos Pósa, relates two parameters of a graph:
The size of the largest collection of vertex-disjoint cycles contained in the graph;
The size of the smallest feedback vertex set in the graph: a set that contains one vertex from every cycle.
Motivation and statement
In many applications, we are interested in finding a minimum feedback vertex set in a graph: a small set that includes one vertex from every cycle, or, equivalently, a small set of vertices whose removal destroys all cycles. This is a hard computational problem; if we are not able to solve it exactly, we can instead try to find lower and upper bounds on the size of the minimum feedback vertex set.
One approach to find lower bounds is to find a collection of vertex-disjoint cycles in a graph. For example, consider the graph in Figure 1. The cycles A-B-C-F-A and G-H-I-J-G share no vertices. As a result, if we want to remove vertices and destroy all cycles in the graph, we must remove at least two vertices: one from the first cycle and one from the second. This line of reasoning generalizes: if we can find vertex-disjoint cycles in a graph, then every feedback vertex set in the graph must have at least vertices.
Unfortunately, in general, this bound is not tight: if the largest collection of vertex-disjoint cycles in a graph contains cycles, then it does not necessarily follow that there is a feedback vertex set of size . The graph in Figure 1 is an example of this: even if we destroy cycle G-H-I-J-G by removing one of the vertices G, H, I, or J, we cannot destroy all four of the cycles A-B-C-F-A, A-B-E-F-A, B-C-D-E-B, and C-D-E-F-C by removing only one more vertex. Any minimum feedback vertex set in the graph in Figure 1 has three vertices: for example, the three vertices A, C, and G.
It is possible to construct examples in which the gap between the two quantities - the size of the largest collecti |
https://en.wikipedia.org/wiki/Astaxanthin | Astaxanthin is a keto-carotenoid within a group of chemical compounds known as terpenes. Astaxanthin is a metabolite of zeaxanthin and canthaxanthin, containing both hydroxyl and ketone functional groups. It is a lipid-soluble pigment with red coloring properties, which result from the extended chain of conjugated (alternating double and single) double bonds at the center of the compound.
Astaxanthin is produced naturally in the freshwater microalgae Haematococcus pluvialis and the yeast fungus Xanthophyllomyces dendrorhous (also known as Phaffia rhodozyma). When the algae are stressed by lack of nutrients, increased salinity, or excessive sunshine, they create astaxanthin. Animals who feed on the algae, such as salmon, red trout, red sea bream, flamingos, and crustaceans (shrimp, krill, crab, lobster, and crayfish), subsequently reflect the red-orange astaxanthin pigmentation.
Astaxanthin is used as a dietary supplement for human, animal, and aquaculture consumption. Astaxanthin from algae, synthetic and bacterial sources is generally recognized as safe in the United States. The US Food and Drug Administration has approved astaxanthin as a food coloring (or color additive) for specific uses in animal and fish foods. The European Commission considers it as a food dye with E number E161j. The European Food Safety Authority has set an Acceptable Daily Intake of 0.2 mg per kg body weight, as of 2019. As a food color additive, astaxanthin and astaxanthin dimethyldisuccinate are restricted for use in Salmonid fish feed only.
Natural sources
Astaxanthin is present in most red-coloured aquatic organisms. The content varies from species to species, but also from individual to individual as it is highly dependent on diet and living conditions. Astaxanthin, and other chemically related asta-carotenoids, has also been found in a number of lichen species of the arctic zone.
The primary natural sources for industrial production of astaxanthin comprise the following:
Eu |
https://en.wikipedia.org/wiki/State%20microbe | A state microbe is a microorganism used as an official state symbol. Several U.S. states have honored microorganisms by nominating them to become official state symbols. The first state to declare an Official State Microbe is Oregon which chose Saccharomyces cerevisiae (brewer's or baker's yeast) as the Official Microbe of the State of Oregon in 2013 for its significance to the craft beer industry in Oregon. One of the first proponents of State Microbes was microbiologist Moselio Schaechter, who, in 2010, commented on Official Microbes for the American Society for Microbiology's blog "Small Things Considered" as well as on National Public Radio's "All Things Considered".
Wisconsin 2009: Lactococcus lactis, proposed, not passed
In November 2009, Assembly Bill 556 that proposed designating Lactococcus lactis as Wisconsin state microbe was introduced by Representatives Hebl, Vruwink, Williams, Pasch, Danou, and Fields; it was cosponsored by Senator Taylor. Although the bill passed the Assembly 56 to 41, It was not acted on by the Senate. The proposed AB 556 simply stated that Lactococcus lactis is the State Microbe and should be included in the Wisconsin Blue Book, an almanac containing information on the state of Wisconsin, published by Wisconsin's Legislative Reference Bureau.Lactococcus lactis was proposed as the State Microbe because of its crucial contribution to the cheese industry in Wisconsin. Wisconsin is the largest cheese producer in the United States, producing 3.1 billion pounds of cheese, 26% of all cheese in the US, in more than 600 varieties (2017 data).
Lactococcus lactis is vital for manufacturing cheeses such as Cheddar, Colby, cottage cheese, cream cheese, Camembert, Roquefort, and Brie, as well as other dairy products like cultured butter, buttermilk, sour cream, and kefir. It may also be used for vegetable fermentations such as cucumber pickles and sauerkraut.
Hawaii 2013-14: Flavobacterium akiainvivens and/or Aliivibrio fischeri
In January 2 |
https://en.wikipedia.org/wiki/Searching%20the%20conformational%20space%20for%20docking | In molecular modelling, docking is a method which predicts the preferred orientation of one molecule to another when bound together in a stable complex. In the case of protein docking, the search space consists of all possible orientations of the protein with respect to the ligand. Flexible docking in addition considers all possible conformations of the protein paired with all possible conformations of the ligand.
With present computing resources, it is impossible to exhaustively explore these search spaces; instead, there are many strategies which attempt to sample the search space with optimal efficiency. Most docking programs in use account for a flexible ligand, and several attempt to model a flexible protein receptor. Each "snapshot" of the pair is referred to as a pose.
Molecular dynamics (MD) simulations
In this approach, proteins are typically held rigid, and the ligand is allowed to freely explore their conformational space. The generated conformations are then docked successively into the protein, and an MD simulation consisting of a simulated annealing protocol is performed. This is usually supplemented with short MD energy minimization steps, and the energies determined from the MD runs are used for ranking the overall scoring. Although this is a computer-expensive method (involving potentially hundreds of MD runs), it has some advantages: for example, no specialized energy/scoring functions are required. MD force-fields can typically be used to find poses that are reasonable and can be compared with experimental structures.
The Distance Constrained Essential Dynamics method (DCED) has been used to generate multiple structures for docking, called eigenstructures. This approach, although avoiding most of the costly MD calculations, can capture the essential motions involved in a flexible receptor, representing a form of coarse-grained dynamics.
Shape-complementarity methods
The most common technique used in many docking programs, shape-complemen |
https://en.wikipedia.org/wiki/Help%20key | A Help key, found in the shape of a dedicated key explicitly labeled , or as another key, typically one of the function keys, on a computer keyboard, is a key which, when pressed, produces information on the screen/display to aid the user in their current task, such as using a specific function in an application program.
In the case of a non-dedicated Help key, the location of the key will sometimes vary between different software packages. Most common in computer history, however, is the development of a de facto Help key location for each brand/family of computer, exemplified by the use of F1 on IBM compatible PCs.
Apple keyboards
On a full-sized Apple keyboard, the help key was labelled simply as , located to the left of the . Where IBM compatible PC keyboards had the , Apple keyboards had the help key instead. As of 2007, new Apple keyboards do not have a help key. In its place, a full-sized Apple keyboard has a instead. Instead of a mechanical help key, the menu bar for most applications contain a Help menu as a matter of convention.
Commodore and Amiga keyboards
The Commodore 128 had a key in the second block of top row keys. Amiga keyboards had a key, labelled as such, above the arrow keys on the keyboard, and next to a key (where the cluster is on a standard PC keyboard).
Atari keyboards
The keyboards of the Atari 16- and 32-bit computers had a key above the arrow keys on the keyboard. Atari 8-bit XL and XE series keyboards had dedicated keys, but in the group of differently-styled system keys separated from the rest of the keyboard.
Sun Microsystems (Oracle)
Most of the Sun Microsystems keyboards have a dedicate "" key in the left top corner (left from the "" key above block of 10 () extra keys. |
https://en.wikipedia.org/wiki/Coriolis%20frequency | The Coriolis frequency ƒ, also called the Coriolis parameter or Coriolis coefficient, is equal to twice the rotation rate Ω of the Earth multiplied by the sine of the latitude .
The rotation rate of the Earth (Ω = 7.2921 × 10−5 rad/s) can be calculated as 2π / T radians per second, where T is the rotation period of the Earth which is one sidereal day (23 h 56 min 4.1 s). In the midlatitudes, the typical value for is about 10−4 rad/s. Inertial oscillations on the surface of the Earth have this frequency. These oscillations are the result of the Coriolis effect.
Explanation
Consider a body (for example a fixed volume of atmosphere) moving along at a given latitude at velocity in the Earth's rotating reference frame. In the local reference frame of the body, the vertical direction is parallel to the radial vector pointing from the center of the Earth to the location of the body and the horizontal direction is perpendicular to this vertical direction and in the meridional direction. The Coriolis force (proportional to ), however, is perpendicular to the plane containing both the earth's angular velocity vector (where ) and the body's own velocity in the rotating reference frame . Thus, the Coriolis force is always at an angle with the local vertical direction. The local horizontal direction of the Coriolis force is thus . This force acts to move the body along longitudes or in the meridional directions.
Equilibrium
Suppose the body is moving with a velocity such that the centripetal and Coriolis (due to ) forces on it are balanced. This gives
where is the radius of curvature of the path of object (defined by ). Replacing , where is the magnitude of the spin rate of the Earth, to obtain
Thus the Coriolis parameter, , is the angular velocity or frequency required to maintain a body at a fixed circle of latitude or zonal region. If the Coriolis parameter is large, the effect of the Earth's rotation on the body is significant since it will need a larger an |
https://en.wikipedia.org/wiki/Muramyl%20ligase | The bacterial cell wall provides strength and rigidity to counteract internal osmotic pressure, and protection against the environment. The peptidoglycan layer gives the cell wall its strength, and helps maintain the overall shape of the cell. The basic peptidoglycan structure of both Gram-positive and Gram-negative bacteria comprises a sheet of glycan chains connected by short cross-linking polypeptides. Biosynthesis of peptidoglycan is a multi-step (11-12 steps) process comprising three main stages:
formation of UDP-N-acetylmuramic acid (UDPMurNAc) from N-acetylglucosamine (GlcNAc).
addition of a short polypeptide chain to the UDPMurNAc.
addition of a second GlcNAc to the disaccharide-pentapeptide building block and transport of this unit through the cytoplasmic membrane and incorporation into the growing peptidoglycan layer.
Stage two involves four key Mur ligase enzymes: MurC, MurD, MurE (EC) and MurF (EC). These four Mur ligases are responsible for the successive additions of L-alanine, D-glutamate, meso-diaminopimelate or L-lysine, and D-alanyl-D-alanine to UDP-N-acetylmuramic acid. All four Mur ligases are topologically similar to one another, even though they display low sequence identity. They are each composed of three domains: an N-terminal Rossmann-fold domain responsible for binding the UDPMurNAc substrate; a central domain (similar to ATP-binding domains of several ATPases and GTPases); and a C-terminal domain (similar to dihydrofolate reductase fold) that appears to be associated with binding the incoming amino acid. The conserved sequence motifs found in the four Mur enzymes also map to other members of the Mur ligase family, including folylpolyglutamate synthetase, cyanophycin synthetase and the capB enzyme from Bacillales.
This family includes UDP-N-acetylmuramate-L-alanine ligase (MurC), UDP-N-acetylmuramoylalanyl-D-glutamate-2,6-diaminopimelate ligase (MurE), and UDP-N-acetylmuramoyl-tripeptide-D-alanyl-D-alanine ligase (MurF). This entry |
https://en.wikipedia.org/wiki/Ice%20Queen%20%28song%29 | "Ice Queen" is a song by Dutch symphonic metal band Within Temptation. It was released in June 2001 as the second single from their second studio album Mother Earth. The song was the band's commercial breakthrough, and it remains one of the band's most successful songs to date in Europe. It has been featured on the annual Dutch Top 2000 since 2011.
Along with the singles "Mother Earth," "Angels," and "Stand My Ground", "Ice Queen" has become one of the band's signature songs and is played as ending song on the setlist on almost every concert, except for some shows of The Unforgiving Tour onwards, where they started to end with the songs "Mother Earth" or "Stairway to the Skies".
Lyrics
Like many of Within Temptation's songs, the lyrics of Ice Queen take their inspiration from nature.
"It's a song about nature", said vocalist Sharon den Adel, in an interview with Dennis Weening on Westpop. "And how things go in nature". Guitarist Robert Westerholt further added that "it's about winter".
Video
There are two official videos for the song "Ice Queen". The first video, released only in the Netherlands even though it is generally known as the "German Version", starts with a girl checking a website for concert videos. Then she finds two links, one saying 'Within Temptation'. She clicks on that link and their concert in Landgraaf in 2001, is shown on her screen. While watching the concert on her computer, she clicks on a couple of links and information on the band appears on her screen.
The second video was made for international release. Sharon, the singer, is dancing on a background of a blue, starry sky. She is wearing a white dress and has white extensions in her hair. The other band members are also shown before various backgrounds made with green-screen effects. Such as Robert, the rhythm guitarist, who is shown on a background of fire, or the drummer, who is shown on a background of a thunderstorm. After a while, all band members are shown together on a red planet |
https://en.wikipedia.org/wiki/Feature%20scaling | Feature scaling is a method used to normalize the range of independent variables or features of data. In data processing, it is also known as data normalization and is generally performed during the data preprocessing step.
Motivation
Since the range of values of raw data varies widely, in some machine learning algorithms, objective functions will not work properly without normalization. For example, many classifiers calculate the distance between two points by the Euclidean distance. If one of the features has a broad range of values, the distance will be governed by this particular feature. Therefore, the range of all features should be normalized so that each feature contributes approximately proportionately to the final distance.
Another reason why feature scaling is applied is that gradient descent converges much faster with feature scaling than without it.
It's also important to apply feature scaling if regularization is used as part of the loss function (so that coefficients are penalized appropriately).
Methods
Rescaling (min-max normalization)
Also known as min-max scaling or min-max normalization, rescaling is the simplest method and consists in rescaling the range of features to scale the range in [0, 1] or [−1, 1]. Selecting the target range depends on the nature of the data. The general formula for a min-max of [0, 1] is given as:
where is an original value, is the normalized value. For example, suppose that we have the students' weight data, and the students' weights span [160 pounds, 200 pounds]. To rescale this data, we first subtract 160 from each student's weight and divide the result by 40 (the difference between the maximum and minimum weights).
To rescale a range between an arbitrary set of values [a, b], the formula becomes:
where are the min-max values.
Mean normalization
where is an original value, is the normalized value, is the mean of that feature vector. There is another form of the means normalization which divid |
https://en.wikipedia.org/wiki/List%20of%20common%20names%20of%20lichen%20genera | This is a list of common names of lichen genera. When a common name for a lichen genus is the same as the scientific name for that genus, it is not included in the following list. This list only includes genera common names that are widely used, as indicated by the common name either appearing in a peer reviewed scientific publication or in a scientifically reliable reference source.
A common name for a lichen genus will often uniquely refer to that genus, but not always. Sometimes the same common name may refer to several different genera, which may not be related by sharing common ancestry. An example is that "wart lichen" refers to at least five different genera in four different families. Sometimes the same genus may have more than one widely used common name. For example, members of the genus Staurothele are commonly called "wart lichens", and also "rock pimples". Lichen genus common names my come from the shape, color, or other feature of some members of a genus. Other members may not share that trait, but are still referred to by the common name for the genus. For example, Caloplaca albovariegata is an orange lichen, but it is not orange in color.
Lichen species common names are often the same as the common name of the genus they are in, or are a modification of that common name by adding an adjective. But sometimes the parts of a lichen species common name are common names of other lichen genera. For example, Psilolechia lucida, in the genus Psilolechia, is commonly called "sulphur dust lichen". But "sulphur lichen" refers to the genus Fulgensia, and "dust lichen" refers either to the genus Chrysothrix or the genus Lepraria.
B
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https://en.wikipedia.org/wiki/Extracellular%20signal-regulated%20kinases | In molecular biology, extracellular signal-regulated kinases (ERKs) or classical MAP kinases are widely expressed protein kinase intracellular signalling molecules that are involved in functions including the regulation of meiosis, mitosis, and postmitotic functions in differentiated cells. Many different stimuli, including growth factors, cytokines, virus infection, ligands for heterotrimeric G protein-coupled receptors, transforming agents, and carcinogens, activate the ERK pathway.
The term, "extracellular signal-regulated kinases", is sometimes used as a synonym for mitogen-activated protein kinase (MAPK), but has more recently been adopted for a specific subset of the mammalian MAPK family.
In the MAPK/ERK pathway, Ras activates c-Raf, followed by mitogen-activated protein kinase kinase (abbreviated as MKK, MEK, or MAP2K) and then MAPK1/2 (below). Ras is typically activated by growth hormones through receptor tyrosine kinases and GRB2/SOS, but may also receive other signals. ERKs are known to activate many transcription factors, such as ELK1, and some downstream protein kinases.
Disruption of the ERK pathway is common in cancers, especially Ras, c-Raf, and receptors such as HER2.
Mitogen-activated protein kinase 1
Mitogen-activated protein kinase 1 (MAPK1) is also known as extracellular signal-regulated kinase 2 (ERK2). Two similar protein kinases with 85% sequence identity were originally called ERK1 and ERK2. They were found during a search for protein kinases that are rapidly phosphorylated after activation of cell surface tyrosine kinases such as the epidermal growth factor receptor. Phosphorylation of ERKs leads to the activation of their kinase activity.
The molecular events linking cell surface receptors to activation of ERKs are complex. It was found that Ras GTP-binding proteins are involved in the activation of ERKs. Another protein kinase, Raf-1, was shown to phosphorylate a "MAP kinase-kinase", thus qualifying as a "MAP kinase kinase kina |
https://en.wikipedia.org/wiki/BATON%20Overlay | The BAlanced Tree Overlay Network (BATON) is a distributed tree structure designed for peer-to-peer (P2P) systems. Unlike other overlays that utilize a distributed hash table (DHT) like the Chord system, BATON organizes peers in a distributed tree to facilitate range search. Furthermore, BATON aims to maintain a balanced tree height, similar to the AVL tree, resulting in a bounded to for search exact and range queries as well as update operations (join/leave).
System model
BATON is a binary tree. In each tree level, the node is named by its position in the tree.
Each node in BATON keeps four kinds of links:
a link to its parent node (unless it is root)
links up to two-children nodes
a link to left and right adjacent node
links to select neighbor nodes maintained in a left routing table (LRT) and right routing table (RRT). Combining these, the routing table is created
The level of any node is one greater than the level of its parent. Root is on level 0. For a node at position , it will fill its left routing table by nodes at position for any valid and fill its right routing table by nodes at position for any valid . The construction of the routing table has slight resemblance to the finger tables in Chord.
So according to the example structure, node 2:1 would keep links to
1:0 (parent)
3:2 (children)
0:0 and 3:2 (adjacent)
2:0, 2:2 and 2:3 (neighbors)
Height-Balanced
BATON is considered balanced if and only if the height of its two sub-trees at any node in the tree differs by at most one. If any node detects that the height-balanced constraint is violated, a restructuring process is initiated to ensure that the tree remains balanced.
Node joining and leaving
When a new node wants to join the network in BATON, its joining request is always forwarded to the leaf node. The leaf node then checks whether its routing table is full. If the table is full, it means that the level is full of nodes, and the leaf node can accept the new node as its child to |
https://en.wikipedia.org/wiki/Topology%20control | Topology control is a technique used in distributed computing to alter the underlying network (modeled as a graph) to reduce the cost of distributed algorithms if run over the resulting graphs. It is a basic technique in distributed algorithms. For instance, a (minimum) spanning tree is used as a backbone to reduce the cost of broadcast from O(m) to O(n), where m and n are the number of edges and vertices in the graph, respectively.
The term "topology control" is used mostly by the wireless ad hoc and sensor networks research community. The main aim of topology control in this domain is to save energy, reduce interference between nodes and extend lifetime of the network. However, recently the term has also been gaining traction with regards to control of the network structure of electric power systems.
Topology construction and maintenance
Lately, topology control algorithms have been divided into two subproblems: topology construction, in charge of the initial reduction, and topology maintenance, in charge of the maintenance of the reduced topology so that characteristics like connectivity and coverage are preserved.
This is the first stage of a topology control protocol. Once the initial topology is deployed, specially when the location of the nodes is random, the administrator has no control over the design of the network; for example, some areas may be very dense, showing a high number of redundant nodes, which will increase the number of message collisions and will provide several copies of the same information from similarly located nodes. However, the administrator has control over some parameters of the network: transmission power of the nodes, state of the nodes (active or sleeping), role of the nodes (Clusterhead, gateway, regular), etc. By modifying these parameters, the topology of the network can change.
Upon the same time a topology is reduced and the network starts serving its purpose, the selected nodes start spending energy: Reduced topology st |
https://en.wikipedia.org/wiki/Independent%20software%20vendor | An independent software vendor (ISV), also known as a software publisher, is an organization specializing in making and selling software, as opposed to computer hardware, designed for mass or niche markets. This is in contrast to in-house software, which is developed by the organization that will use it, or custom software, which is designed or adapted for a single, specific third party. Although ISV-provided software is consumed by end users, it remains the property of the vendor.
Software products developed by ISVs serve a wide variety of purposes. Examples include software for real estate brokers, scheduling for healthcare personnel, barcode scanning, stock maintenance, gambling, retailing, energy exploration, vehicle fleet management, and child care management software.
An ISV makes and sells software products that run on one or more computer hardware or operating system platforms. Companies that make the platforms, such as Microsoft, AWS, Cisco, IBM, Hewlett-Packard, Red Hat, Google, Oracle, VMware, Lenovo, Apple, SAP, Salesforce and ServiceNow encourage and lend support to ISVs, often with special "business partner" programs. These programs enable the platform provider and the ISV to leverage joint strengths and convert them into incremental business opportunities.
Independent software vendors have become one of the primary groups in the IT industry, often serving as relays to disseminate new technologies and solutions.
See also
Commercial off-the-shelf
Software company
Micro ISV |
https://en.wikipedia.org/wiki/Permutoassociahedron | In mathematics, the permutoassociahedron is an -dimensional polytope whose vertices correspond to the bracketings of the permutations of terms and whose edges connect two bracketings that can be obtained from one another either by moving a pair of brackets using associativity or by transposing two consecutive terms that are not separated by a bracket.
The permutoassociahedron was first defined as a CW complex by Mikhail Kapranov who noted that this structure appears implicitly in Mac Lane's coherence theorem for symmetric and braided categories as well as in Vladimir Drinfeld's work on the Knizhnik–Zamolodchikov equations. It was constructed as a convex polytope by Victor Reiner and Günter M. Ziegler.
Examples
When , the vertices of the permutoassociahedron can be represented by bracketing all the permutations of three terms , , and . There are six such permutations, , , , , , and , and each of them admits two bracketings (obtained from one another by associativity). For instance, can be bracketed as or as . Hence, the -dimensional permutoassociahedron is the dodecagon with vertices , , , , , , , , , , , and .
When , the vertex is adjacent to exactly three other vertices of the permutoassociahedron: , , and . The first two vertices are reached from via associativity and the third via a transposition. The vertex is adjacent to four vertices. Two of them, and , are reached via associativity, and the other two, and , via a transposition. This illustrates that, in dimension and above, the permutoassociahedron is not a simple polytope.
Properties
The -dimensional permutoassociahedron has
vertices. This is the product between the number of permutations of terms and the number of all possible bracketings of any such permutation. The former number is equal to the factorial and the later is the th Catalan number.
By its description in terms of bracketed permutations, the 1-skeleton of the permutoassociahedron is a flip graph with two different kinds of |
https://en.wikipedia.org/wiki/%CE%9418O | {{DISPLAYTITLE:δ18O}}
In geochemistry, paleoclimatology and paleoceanography δ18O or delta-O-18 is a measure of the ratio of stable isotopes oxygen-18 (18O) and oxygen-16 (16O).
It is commonly used as a measure of the temperature of precipitation, as a measure of groundwater/mineral interactions, and as an indicator of processes that show isotopic fractionation, like methanogenesis.
In paleosciences, 18O:16O data from corals, foraminifera and ice cores are used as a proxy for temperature.
The definition is, in "per mil" (‰, parts per thousand):
‰
where the standard has a known isotopic composition, such as Vienna Standard Mean Ocean Water (VSMOW). The fractionation can arise from kinetic, equilibrium, or mass-independent fractionation.
Mechanism
Foraminifera shells are composed of calcium carbonate (CaCO3) and are found in many common geological environments. The ratio of 18O to 16O in the shell is used to indirectly determine the temperature of the surrounding water at the time the shell was formed. The ratio varies slightly depending on the temperature of the surrounding water, as well as other factors such as the water's salinity, and the volume of water locked up in ice sheets.
also reflects local evaporation and freshwater input, as rainwater is 16O-enriched—a result of the preferential evaporation of the lighter 16O from seawater. Consequently, the surface ocean contains greater proportions of 18O around the subtropics and tropics where there is more evaporation, and lesser proportions of 18O in the mid-latitudes where it rains more.
Similarly, when water vapor condenses, heavier water molecules holding 18O atoms tend to condense and precipitate first. The water vapor gradient heading from the tropics to the poles gradually becomes more and more depleted of 18O. Snow falling in Canada has much less H218O than rain in Florida; similarly, snow falling in the center of ice sheets has a lighter signature than that at its margins, since heavier 18O p |
https://en.wikipedia.org/wiki/Journal%20of%20Combinatorial%20Theory | The Journal of Combinatorial Theory, Series A and Series B, are mathematical journals specializing in combinatorics and related areas. They are published by Elsevier. Series A is concerned primarily with structures, designs, and applications of combinatorics. Series B is concerned primarily with graph and matroid theory. The two series are two of the leading journals in the field and are widely known as JCTA and JCTB.
The journal was founded in 1966 by Frank Harary and Gian-Carlo Rota. Originally there was only one journal, which was split into two parts in 1971 as the field grew rapidly.
In 2020, most of the editorial board of JCTA resigned to form a new, open access journal Combinatorial Theory. The new journal aims to be a continuation of JCTA independently from Elsevier. It published its first issue in December 2021.
Influential articles
Influential articles that appeared in the journal include Katona's elegant proof of the Erdős–Ko–Rado theorem and a series of papers spanning over 500 pages, appearing from 1983 to 2004, by Neil Robertson and Paul D. Seymour on the topic of graph minors, which together constitute the proof of the graph minors theorem. Two articles proving Kneser's conjecture, the first by László Lovász and the other by Imre Bárány, appeared back-to-back in the same issue of the journal. |
https://en.wikipedia.org/wiki/Rho-associated%20protein%20kinase | Rho-associated protein kinase (ROCK) is a kinase belonging to the AGC (PKA/ PKG/PKC) family of serine-threonine specific protein kinases. It is involved mainly in regulating the shape and movement of cells by acting on the cytoskeleton.
ROCKs (ROCK1 and ROCK2) occur in mammals (human, rat, mouse, cow), zebrafish, Xenopus, invertebrates (C. elegans, mosquito, Drosophila) and chicken. Human ROCK1 has a molecular mass of 158 kDa and is a major downstream effector of the small GTPase RhoA. Mammalian ROCK consists of a kinase domain, a coiled-coil region and a Pleckstrin homology (PH) domain, which reduces the kinase activity of ROCKs by an autoinhibitory intramolecular fold if RhoA-GTP is not present.
Rat ROCKs were discovered as the first effectors of Rho and they induce the formation of stress fibers and focal adhesions by phosphorylating MLC (myosin light chain).
Due to this phosphorylation, the actin binding of myosin II and, thus, the contractility increases. Two mouse ROCK isoforms ROCK1 and ROCK2 have been identified. ROCK1 is mainly expressed in the lung, liver, spleen, kidney and testis. However, ROCK2 is distributed mostly in the brain and heart.
Protein kinase C and Rho-associated protein kinase are involved in regulating calcium ion intake; these calcium ions, in turn stimulate a myosin light chain kinase, forcing a contraction. Rho-associated protein kinase are serine or threonine kinases that determine the calcium sensitivity in smooth muscle cells.
Function
ROCK plays a role in a wide range of different cellular phenomena, as ROCK is a downstream effector protein of the small GTPase Rho, which is one of the major regulators of the cytoskeleton.
1. ROCK is a key regulator of actin organization and thus a regulator of cell migration as follows:
Different substrates can be phosphorylated by ROCKs, including LIM kinase, myosin light chain (MLC) and MLC phosphatase. These substrates, once phosphorylated, regulate actin filament organization and contra |
https://en.wikipedia.org/wiki/Sensistor | Sensistor is a resistor whose resistance changes with temperature.
The resistance increases exponentially with temperature, that is the temperature coefficient is positive (e.g. 0.7% per degree Celsius).
Sensistors are used in electronic circuits for compensation of temperature influence or as sensors of temperature for other circuits.
Sensistors are made by using very heavily doped semiconductors so that their operation is similar to PTC-type thermistors. However, very heavily doped semiconductor behaves more like a metal and the resistance change is more gradual than it is the case for other PTC thermistors.
See also
thermistor |
https://en.wikipedia.org/wiki/United%20Kingdom%20Rocketry%20Association | The United Kingdom Rocketry Association (UKRA) is an enabling body set up to promote and represent high power, medium power and model rocketry in the United Kingdom for educational, recreational and amateur research purposes. UKRA is also the specialist body to the BMFA (British Model Flying Association) with responsibilities for High Power Rocketry, and is the United Kingdom body recognized by the Civil Aviation Authority.
Background
Formed in 1996 at a meeting of UK rocketry societies and clubs established at that time, as well as amateur rocketeers, the formation meeting took place at the International Rocket Week at Largs in Scotland. UKRA works through the current UKRA affiliated rocketry clubs and societies. These rocketry clubs and societies organise rocket launches which take place on a monthly basis at their launch sites. UKRA liaises with government bodies on behalf of UK rocketeers and, through its certification programme and network of Range Safety Officers, ensures safe launches. UKRA has safety rules to ensure that rocket launching takes place in clear skies, and care is taken to ensure that the planned trajectory avoids any passing aircraft. In addition, Notice to Airmen (NOTAM's) are issued to pilots of aircraft notifying them of the rocket launching site and times of rocketry activity. UKRA also has a reciprocal certification arrangement with U.S. equivalent, the Tripoli Rocketry Association (TRA).
UKRA also provides, through the BMFA, 3rd party liability insurance of up to £25 million which is included in Full UKRA membership and allows rocket motors of up to M-class (10,240 Newton seconds total impulse) to be used with the correct certification. UKRA's Large Rocket Scheme caters for rockets exceeding 10,240 Newton seconds total impulse. UKRA also maintains a comprehensive set of tables of UK amateur and experimental rocketry records, and a procedure to enable records to be verified.
Youth programmes
With the Model Achievement Programme, UKRA |
https://en.wikipedia.org/wiki/Half-integer | In mathematics, a half-integer is a number of the form
where is a whole number. For example,
are all half-integers. The name "half-integer" is perhaps misleading, as the set may be misunderstood to include numbers such as 1 (being half the integer 2). A name such as "integer-plus-half" may be more accurate, but even though not literally true, "half integer" is the conventional term. Half-integers occur frequently enough in mathematics and in quantum mechanics that a distinct term is convenient.
Note that halving an integer does not always produce a half-integer; this is only true for odd integers. For this reason, half-integers are also sometimes called half-odd-integers. Half-integers are a subset of the dyadic rationals (numbers produced by dividing an integer by a power of two).
Notation and algebraic structure
The set of all half-integers is often denoted
The integers and half-integers together form a group under the addition operation, which may be denoted
However, these numbers do not form a ring because the product of two half-integers is not a half-integer; e.g. The smallest ring containing them is , the ring of dyadic rationals.
Properties
The sum of half-integers is a half-integer if and only if is odd. This includes since the empty sum 0 is not half-integer.
The negative of a half-integer is a half-integer.
The cardinality of the set of half-integers is equal to that of the integers. This is due to the existence of a bijection from the integers to the half-integers: , where is an integer
Uses
Sphere packing
The densest lattice packing of unit spheres in four dimensions (called the D4 lattice) places a sphere at every point whose coordinates are either all integers or all half-integers. This packing is closely related to the Hurwitz integers: quaternions whose real coefficients are either all integers or all half-integers.
Physics
In physics, the Pauli exclusion principle results from definition of fermions as particles which have spins |
https://en.wikipedia.org/wiki/Bryophilous%20lichen | A bryophilous lichen is one that grows on a bryophyte – that is, on a moss or liverwort. Those which grow on mosses are known as muscicolous lichens, while those grow on liverworts are called hepaticolous lichens. Muscicolous derives from the Latin muscus meaning moss, while the suffix colous means "living or growing in or on". Lichens are slow-growing organisms, and so are far more likely to be overgrown by a bryophyte than to overgrow one. However, they are better able to compete if the bryophyte is sickly or decaying and they can be parasitic upon them. Some, rather than overgrowing the bryophyte, instead live among its branches. Bryophilous lichens are particularly common in heathland and arctic or alpine tundra. Because many are small and inconspicuous, they are easy to overlook.
Citations |
https://en.wikipedia.org/wiki/Boo%20Boo%20%28dog%29 | Boo Boo was the world's smallest dog from 2007 to 2013. She stood at a height of 9.65 cm, according to the Guinness Book of World Records.
Boo Boo was replaced by Milly, another Chihuahua, as the World's Smallest Dog. Other contenders for the record included Beyonce, a Dachshund-Chihuahua mix, and Scooter, a Maltese
See also
List of individual dogs
Boo (dog) |
https://en.wikipedia.org/wiki/Russell%20Varian%20Prize | The Russell Varian Prize was an international scientific prize awarded for a single, high-impact and innovative contribution in the field of nuclear magnetic resonance (NMR), that laid the foundation for the development of new technologies in the field. It honored the memory of Russell Varian, the pioneer behind the creation of the first commercial NMR spectrometer and the co-founder, in 1948, of Varian Associates, one of the first high-tech companies in Silicon Valley. The prize carried a monetary award of €15,000 and it was awarded annually between the years 2002 and 2015 (except for 2003) by a committee of experts in the field. The award ceremony alternated between the European Magnetic Resonance (EUROMAR) Conference and the International Council on Magnetic Resonance in Biological Systems (ICMRBS) Conference. Originally, the prize was sponsored by Varian, Inc. and later by Agilent Technologies, after the latter acquired Varian, Inc. in 2010. The prize was discontinued in 2016 after Agilent Technologies closed its NMR division.
Russell Varian Prize Awardees
2002 Jean Jeener. Contribution: Multi-dimensional Fourier NMR spectroscopy.
2004 Erwin L. Hahn. Contribution: Spin echo phenomena and experiments.
2005 Nicolaas Bloembergen. Contribution: Nuclear magnetic relaxation.
2006 John S. Waugh. Contribution: Average Hamiltonian theory.
2007 Alfred G. Redfield. Contribution: Relaxation Theory.
2008 Alexander Pines. Contribution: Cross-polarization method for NMR in solids.
2009 Albert W. Overhauser. Contribution: Nuclear Overhauser effect (NOE).
2010 Martin Karplus. Contribution: Karplus equation.
2011 Gareth A. Morris. Contribution: INEPT pulse sequence.
2012 Ray Freeman and Weston A. Anderson. Contribution: Double resonance.
2013 Lucio Frydman. Contribution: Ultrafast NMR.
2014 Ad Bax. Contribution: Homonuclear broad band decoupled absorption spectra.
2015 Malcolm Levitt. Contribution: Composite pulses.
See also
List of physics awards |
https://en.wikipedia.org/wiki/Enhancer%20%28genetics%29 | In genetics, an enhancer is a short (50–1500 bp) region of DNA that can be bound by proteins (activators) to increase the likelihood that transcription of a particular gene will occur. These proteins are usually referred to as transcription factors. Enhancers are cis-acting. They can be located up to 1 Mbp (1,000,000 bp) away from the gene, upstream or downstream from the start site. There are hundreds of thousands of enhancers in the human genome. They are found in both prokaryotes and eukaryotes.
The first discovery of a eukaryotic enhancer was in the immunoglobulin heavy chain gene in 1983. This enhancer, located in the large intron, provided an explanation for the transcriptional activation of rearranged Vh gene promoters while unrearranged Vh promoters remained inactive.
Locations
In eukaryotic cells the structure of the chromatin complex of DNA is folded in a way that functionally mimics the supercoiled state characteristic of prokaryotic DNA, so although the enhancer DNA may be far from the gene in a linear way, it is spatially close to the promoter and gene. This allows it to interact with the general transcription factors and RNA polymerase II. The same mechanism holds true for silencers in the eukaryotic genome. Silencers are antagonists of enhancers that, when bound to its proper transcription factors called repressors, repress the transcription of the gene. Silencers and enhancers may be in close proximity to each other or may even be in the same region only differentiated by the transcription factor the region binds to.
An enhancer may be located upstream or downstream of the gene it regulates. Furthermore, an enhancer does not need to be located near the transcription initiation site to affect transcription, as some have been found located several hundred thousand base pairs upstream or downstream of the start site. Enhancers do not act on the promoter region itself, but are bound by activator proteins. These activator proteins interact with the med |
https://en.wikipedia.org/wiki/VTPR | VTPR (short for Volume-Translated Peng–Robinson)
is an estimation method for the calculation of phase equilibria of mixtures of chemical components. The original goal for the development of this method was to enable the estimation of properties of mixtures which contain supercritical components. These class of substances couldn't be predicted with established models like UNIFAC.
Principle
VTPR is a group contribution equation of state. This is class of prediction methods combine equations of state (mostly cubic) with activity coefficient models based on group contributions like UNIFAC. The activity coefficient model is used to adapt the equation of state parameters for mixtures by a so-called mixing rule.
The usage of an equation of state introduces all thermodynamic relations defined for equations of state into the VTPR model. This allows the calculation of densities, enthalpies, heat capacities, and more.
Equations
VTPR is based on a combination of the Peng–Robinson equation of state with a mixing rule whose parameters are determined by UNIFAC.
Equation of state
The Peng–Robinson equation of state is defined as follows:
The originally used α-function has been replaced by the function of Twu, Bluck, Cunningham and Coon
.
The parameters of the Twu equation are fitted to experimental vapor pressure data of pure components and guarantee therefore a better description of the vapor pressure than the original relation.
Mixing rule
The VTPR mixing rule calculate the parameter a and b of the equation of state by
with
and
by the parameters ai und bi of the pure substances, their mole fractions xi and the residual part of excess Gibbs energy gE. The excess Gibbs energy is calculated by a modified UNIFAC model.
Model parameters
For the equation of state VTPR needs the critical temperature and pressure and additionally at least the acentric factor for all pure components in the considered mixture.
A better quality can be achieved if the acentric factor is r |
https://en.wikipedia.org/wiki/L%C3%A9vy%E2%80%93Steinitz%20theorem | In mathematics, the Lévy–Steinitz theorem identifies the set of values to which rearrangements of an infinite series of vectors in Rn can converge. It was proved by Paul Lévy in his first published paper when he was 19 years old. In 1913 Ernst Steinitz filled in a gap in Lévy's proof and also proved the result by a different method.
In an expository article, Peter Rosenthal stated the theorem in the following way.
The set of all sums of rearrangements of a given series of vectors in a finite-dimensional real Euclidean space is either the empty set or a translate of a subspace (i.e., a set of the form v + M, where v is a given vector and M is a linear subspace).
See also
Riemann series theorem |
https://en.wikipedia.org/wiki/Radionics | Radionics—also called electromagnetic therapy (EMT) and the Abrams Method—is a form of alternative medicine that claims that disease can be diagnosed and treated by applying electromagnetic radiation (EMR), such as radio waves, to the body from an electrically powered device. It is similar to magnet therapy, which also applies EMR to the body but uses a magnet that generates a static electromagnetic field.
The concept behind radionics originated with two books published by American physician Albert Abrams in 1909 and 1910. Over the next decade, Abrams became a millionaire by leasing EMT machines, which he designed himself. This so-called treatment contradicts the principles of physics and biology and therefore is widely considered pseudoscientific. The United States Food and Drug Administration does not recognize any legitimate medical use for radionic devices.
Several systematic reviews have shown radionics is no more effective than placebo and falls into the category of pseudoscience.
History
Beginning around 1909, Albert Abrams (1864–1924) began to claim that he could detect "energy frequencies" in his patient's bodies. The idea was that a healthy person will have certain energy frequencies moving through their body that define health, while an unhealthy person will exhibit other, different energy frequencies that define disorders. He said he could cure people by "balancing" their discordant frequencies and claimed that his devices are sensitive enough that he could tell someone's religion by looking at a drop of blood. He developed thirteen devices and became a millionaire leasing his devices, and the American Medical Association described him as the "dean of gadget quacks". His devices were definitively proven useless by an independent investigation commissioned by Scientific American in 1924. He used "frequency" not in its standard meaning, but to describe an imputed energy type, which does not correspond to any property of energy in the scientific sens |
https://en.wikipedia.org/wiki/Citrix%20Cloud | Citrix Cloud is a cloud management platform that allows organizations to deploy cloud-hosted desktops and apps to end users. It was developed by Citrix Systems and released in 2015.
Overview
Citrix Cloud is a cloud-based platform for managing and deploying Citrix products and desktops and applications to end users using any type of cloud, whether public, private or hybrid, or on-premises hardware. The product supports cloud-based versions of every major Citrix product. These can be accessed together as an integrated "workspace" or independently.
Features
Citrix Cloud enables cloud services for Citrix products XenApp, XenDesktop, XenMobile, ShareFile, and NetScaler. In addition, Citrix has developed several cloud-native services, including its Secure Browser Service.
Citrix Cloud is compatible with any device and cloud or data center and can be synced via Citrix Cloud Connector. As of May 2016, Citrix states that Microsoft Azure is its preferred cloud partner. Citrix platforms reside in Citrix Cloud, however other applications and resources may make use of other clouds and infrastructures. A company's IT department retains the ability to choose a custom combination of data centers and cloud providers. Citrix continuously updates Citrix Cloud so that users are automatically running the most current version.
As of 2015, Citrix Cloud offers four different service packages.
History
Citrix Workspace Cloud was announced in May 2015 at the company's industry conference, Citrix Synergy. The offering launched in August 2015 with four core services: App and Desktop Service, Lifecycle Management, Secure Documents, and Mobility. The company positioned Workspace Cloud as an alternative to XenDesktop and XenApp, the company's traditional desktop and application virtualization platforms.
The company renamed Citrix Workspace Cloud to Citrix Cloud in May 2016.r In addition, cloud services were renamed with cloud-based versions of other Citrix products. XenDesktop and XenApp Se |
https://en.wikipedia.org/wiki/List%20of%20Rwandan%20flags | The following is a list of flags related with Rwanda.
National flag
Government flag
Ethnic group flag
Political party flags
Historical flags
See also
Flag of Rwanda
Seal of Rwanda |
https://en.wikipedia.org/wiki/Topological%20Yang%E2%80%93Mills%20theory | In gauge theory, topological Yang–Mills theory, also known as the theta term or -term is a gauge-invariant term which can be added to the action for four-dimensional field theories, first introduced by Edward Witten. It does not change the classical equations of motion, and its effects are only seen at the quantum level, having important consequences for CPT symmetry.
Action
Spacetime and field content
The most common setting is on four-dimensional, flat spacetime (Minkowski space).
As a gauge theory, the theory has a gauge symmetry under the action of a gauge group, a Lie group , with associated Lie algebra through the usual correspondence.
The field content is the gauge field , also known in geometry as the connection. It is a -form valued in a Lie algebra .
Action
In this setting the theta term action is
where
is the field strength tensor, also known in geometry as the curvature tensor. It is defined as , up to some choice of convention: the commutator sometimes appears with a scalar prefactor of or , a coupling constant.
is the dual field strength, defined .
is the totally antisymmetric symbol, or alternating tensor. In a more general geometric setting it is the volume form, and the dual field strength is the Hodge dual of the field strength .
is the theta-angle, a real parameter.
is an invariant, symmetric bilinear form on . It is denoted as it is often the trace when is under some representation. Concretely, this is often the adjoint representation and in this setting is the Killing form.
As a total derivative
The action can be written as
where is the Chern–Simons 3-form.
Classically, this means the theta term does not contribute to the classical equations of motion.
Properties of the quantum theory
CP violation
Chiral anomaly
See also
Yang–Mills theory |
https://en.wikipedia.org/wiki/SIGNAL%20%28programming%20language%29 | SIGNAL is a programming language based on synchronized data-flow (flows + synchronization): a process is a set of equations on elementary flows describing both data and control.
The SIGNAL formal model provides the capability to describe systems with several clocks (polychronous systems) as relational specifications. Relations are useful as partial specifications and as specifications of non-deterministic devices (for instance a non-deterministic bus) or external processes (for instance an unsafe car driver).
Using SIGNAL allows one to specify an application, to design an architecture, to refine detailed components down to RTOS or hardware description. The SIGNAL model supports a design methodology which goes from specification to implementation, from abstraction to concretization, from synchrony to asynchrony.
SIGNAL has been mainly developed in INRIAEspresso team since the 1980s, at the same time as similar programming languages, Esterel and Lustre.
A brief history
The SIGNAL language was first designed for signal processing applications in the beginning of the 1980s. It has been proposed to answer the demand of new domain-specific language for the design of signal processing applications, adopting a dataflow and block-diagram style with array and sliding window operators. P. Le Guernic, A. Benveniste, and T. Gautier have been in charge of the language definition. The first paper on SIGNAL was published in 1982, while the first complete description of SIGNAL appeared in the PhD thesis of T. Gautier. The symbolic representation of SIGNAL via z/3z (over [-1,0,1]) has been introduced in 1986. A full compiler of SIGNAL based on the clock calculus on hierarchy of Boolean clocks, was described by L. Besnard in his PhD thesis in 1992. The clock calculus has been improved later by T. Amagbegnon with the proposition of arborescent canonical forms.
During the 1990s, the application domain of the SIGNAL language has been extended into general embedded and real-time sys |
https://en.wikipedia.org/wiki/Yang%E2%80%93Mills%20existence%20and%20mass%20gap | The Yang–Mills existence and mass gap problem is an unsolved problem in mathematical physics and mathematics, and one of the seven Millennium Prize Problems defined by the Clay Mathematics Institute, which has offered a prize of US$1,000,000 for its solution.
The problem is phrased as follows:
Yang–Mills Existence and Mass Gap. Prove that for any compact simple gauge group G, a non-trivial quantum Yang–Mills theory exists on and has a mass gap Δ > 0. Existence includes establishing axiomatic properties at least as strong as those cited in , and .
In this statement, a quantum Yang–Mills theory is a non-abelian quantum field theory similar to that underlying the Standard Model of particle physics; is Euclidean 4-space; the mass gap Δ is the mass of the least massive particle predicted by the theory.
Therefore, the winner must prove that:
Yang–Mills theory exists and satisfies the standard of rigor that characterizes contemporary mathematical physics, in particular constructive quantum field theory, and
The mass of all particles of the force field predicted by the theory are strictly positive.
For example, in the case of G=SU(3)—the strong nuclear interaction—the winner must prove that glueballs have a lower mass bound, and thus cannot be arbitrarily light.
The general problem of determining the presence of a spectral gap in a system is known to be undecidable.
Background
The problem requires the construction of a QFT satisfying the Wightman axioms and showing the existence of a mass gap. Both of these topics are described in sections below.
The Wightman axioms
The Millennium problem requires the proposed Yang–Mills theory to satisfy the Wightman axioms or similarly stringent axioms. There are four axioms:
W0 (assumptions of relativistic quantum mechanics)
Quantum mechanics is described according to von Neumann; in particular, the pure states are given by the rays, i.e. the one-dimensional subspaces, of some separable complex Hilbert space.
The Wight |
https://en.wikipedia.org/wiki/Steinmetz%20curve | A Steinmetz curve is the curve of intersection of two right circular cylinders of radii and whose axes intersect perpendicularly. In case of the Steimetz curves are the edges of a Steinmetz solid. If the cylinder axes are the x- and y-axes and , then the Steinmetz curves are given by the parametric equations:
It is named after mathematician Charles Proteus Steinmetz, along with Steinmetz's equation, Steinmetz solids, and Steinmetz equivalent circuit theory.
In the case when the two cylinders have equal radii the curve degenerates to two intersecting ellipses.
See also
Cylinder |
https://en.wikipedia.org/wiki/Trap%20crop | A trap crop is a plant that attracts agricultural pests, usually insects, away from nearby crops. This form of companion planting can save the main crop from decimation by pests without the use of pesticides.[1] A trap crop is used for attracting the insect and pests away from the field.[1] Many trap crops have successfully diverted pests from focal crops in small scale greenhouse, garden and field experiments; a small portion of these plants have been shown to reduce pest damage at larger commercial scales. A common explanation for reported trap cropping failures, is that attractive trap plants only protect nearby plants if the insects do not move back into the main crop. In a review of 100 trap cropping examples in 2006, only 10 trap crops were classified as successful at a commercial scale, and in all successful cases, trap cropping was supplemented with management practices that specifically limited insect dispersal from the trap crop back into the main crop.
Examples
Examples of trap crops include:
Alfalfa planted in strips among cotton, to draw away lygus bugs, while castor beans surround the field, or tobacco planted in strips among it, to protect from the budworm Heliothis.
Rose enthusiasts often plant Pelargonium geraniums among their rosebushes because Japanese beetles are drawn to the geraniums, which are toxic to them.
Chervil is used by gardeners to protect vegetable plants from slugs.
Rye, sesbania, and sicklepod are used to protect soybeans from corn seeding maggots, stink bugs, and velvet green caterpillars, respectively.
Mustard and alfalfa planted near strawberries to attract lygus bugs, a method pioneered by Jim Cochran.
Blue Hubbard squash is planted near cucurbit crops to attract squash vine borer, squash bugs, and both spotted and striped Cucumber beetle.
In push-pull agricultural pest management, napier grass or signal grass (Brachiaria brizantha) are used as trap crops to attract stemboring moths such as Chilo partellus.
Trap crop |
https://en.wikipedia.org/wiki/Event%20tree%20analysis | Event tree analysis (ETA) is a forward, top-down, logical modeling technique for both success and failure that explores responses through a single initiating event and lays a path for assessing probabilities of the outcomes and overall system analysis. This analysis technique is used to analyze the effects of functioning or failed systems given that an event has occurred.
ETA is a powerful tool that will identify all consequences of a system that have a probability of occurring after an initiating event that can be applied to a wide range of systems including: nuclear power plants, spacecraft, and chemical plants. This technique may be applied to a system early in the design process to identify potential issues that may arise, rather than correcting the issues after they occur. With this forward logic process, use of ETA as a tool in risk assessment can help to prevent negative outcomes from occurring, by providing a risk assessor with the probability of occurrence. ETA uses a type of modeling technique called "event tree", which branches events from one single event using Boolean logic.
History
The name "Event Tree" was first introduced during the WASH-1400 nuclear power plant safety study (circa 1974), where the WASH-1400 team needed an alternate method to fault tree analysis due to the fault trees being too large. Though not using the name event tree, the UKAEA first introduced ETA in its design offices in 1968, initially to try to use whole plant risk assessment to optimize the design of a 500MW Steam-Generating Heavy Water Reactor. This study showed ETA condensed the analysis into a manageable form. ETA was not initially developed during WASH-1400, this was one of the first cases in which it was thoroughly used. The UKAEA study used the assumption that protective systems either worked or failed, with the probability of failure per demand being calculated using fault trees or similar analysis methods. ETA identifies all sequences which follow an initiating |
https://en.wikipedia.org/wiki/Psoriasis | Psoriasis is a long-lasting, noncontagious autoimmune disease characterized by patches of abnormal skin. These areas are red, pink, or purple, dry, itchy, and scaly. Psoriasis varies in severity from small localized patches to complete body coverage. Injury to the skin can trigger psoriatic skin changes at that spot, which is known as the Koebner phenomenon.
The five main types of psoriasis are plaque, guttate, inverse, pustular, and erythrodermic. Plaque psoriasis, also known as psoriasis vulgaris, makes up about 90% of cases. It typically presents as red patches with white scales on top. Areas of the body most commonly affected are the back of the forearms, shins, navel area, and scalp. Guttate psoriasis has drop-shaped lesions. Pustular psoriasis presents as small, noninfectious, pus-filled blisters. Inverse psoriasis forms red patches in skin folds. Erythrodermic psoriasis occurs when the rash becomes very widespread, and can develop from any of the other types. Fingernails and toenails are affected in most people with psoriasis at some point in time. This may include pits in the nails or changes in nail color.
Psoriasis is generally thought to be a genetic disease that is triggered by environmental factors. If one twin has psoriasis, the other twin is three times more likely to be affected if the twins are identical than if they are nonidentical. This suggests that genetic factors predispose to psoriasis. Symptoms often worsen during winter and with certain medications, such as beta blockers or NSAIDs. Infections and psychological stress can also play a role. The underlying mechanism involves the immune system reacting to skin cells. Diagnosis is typically based on the signs and symptoms.
There is no known cure for psoriasis, but various treatments can help control the symptoms. These treatments include steroid creams, vitamin D3 cream, ultraviolet light, immunosuppressive drugs, such as methotrexate, and biologic therapies targeting specific immunologic pat |
https://en.wikipedia.org/wiki/Syagrus%20weddelliana | Syagrus weddelliana, also known as the miniature coconut palm or Weddell's palm, is a feather palm in the palm family.
Description
The palm has a small stature, only growing to a height of . In rare cases, this palm can grow to , with a trunk diameter of about . After flowering, it produces small edible fruits that resemble and taste like coconuts.
Distribution and habitat
This palm is native to the State of Rio de Janeiro in southeastern Brazil. It grows naturally in the rainforests of the region. It is a medium altitude palm, growing in altitudes of . It thrives in the humid shade of the Brazilian rainforests.
Taxonomy
Originally, the palm was placed in the same genus as the coconut palm, under the name Cocos weddelliana, before moving to the queen palm genus, Syagrus, and finally moving to its own genus, Lytocaryum.
Based on morphological and molecular evidence, Larry Noblick and Alan Meerow subsumed Lytocaryum back into Syagrus in 2015.
Horticulture
It is closely related to the coconut palm, but is much smaller and more cold tolerant, taking down to about . This palm can be successfully grown in hardiness zones 10b–11. It has been reported that oil extracted from the nuts has been important commercially. This palm should be grown in well draining soil that is constantly moist, but not soggy, as this can lead to lethal root rot. |
https://en.wikipedia.org/wiki/Data%20model | A data model is an abstract model that organizes elements of data and standardizes how they relate to one another and to the properties of real-world entities. For instance, a data model may specify that the data element representing a car be composed of a number of other elements which, in turn, represent the color and size of the car and define its owner.
The corresponding professional activity is called generally data modeling or, more specifically, database design.
Data models are typically specified by a data expert, data specialist, data scientist, data librarian, or a data scholar.
A data modeling language and notation are often represented in graphical form as diagrams.
A data model can sometimes be referred to as a data structure, especially in the context of programming languages. Data models are often complemented by function models, especially in the context of enterprise models.
A data model explicitly determines the structure of data; conversely, structured data is data organized according to an explicit data model or data structure. Structured data is in contrast to unstructured data and semi-structured data.
Overview
The term data model can refer to two distinct but closely related concepts. Sometimes it refers to an abstract formalization of the objects and relationships found in a particular application domain: for example the customers, products, and orders found in a manufacturing organization. At other times it refers to the set of concepts used in defining such formalizations: for example concepts such as entities, attributes, relations, or tables. So the "data model" of a banking application may be defined using the entity–relationship "data model". This article uses the term in both senses.
Managing large quantities of structured and unstructured data is a primary function of information systems. Data models describe the structure, manipulation, and integrity aspects of the data stored in data management systems such as relational data |
https://en.wikipedia.org/wiki/Morphic%20word | In mathematics and computer science, a morphic word or substitutive word is an infinite sequence of symbols which is constructed from a particular class of endomorphism of a free monoid.
Every automatic sequence is morphic.
Definition
Let f be an endomorphism of the free monoid A∗ on an alphabet A with the property that there is a letter a such that f(a) = as for a non-empty string s: we say that f is prolongable at a. The word
is a pure morphic or pure substitutive word. Note that it is the limit of the sequence a, f(a), f(f(a)), f(f(f(a))), ...
It is clearly a fixed point of the endomorphism f: the unique such sequence beginning with the letter a. In general, a morphic word is the image of a pure morphic word under a coding, that is, a morphism that maps letter to letter.
If a morphic word is constructed as the fixed point of a prolongable k-uniform morphism on A∗ then the word is k-automatic. The n-th term in such a sequence can be produced by a finite state automaton reading the digits of n in base k.
Examples
The Thue–Morse sequence is generated over {0,1} by the 2-uniform endomorphism 0 → 01, 1 → 10.
The Fibonacci word is generated over {a,b} by the endomorphism a → ab, b → a.
The tribonacci word is generated over {a,b,c} by the endomorphism a → ab, b → ac, c → a.
The Rudin–Shapiro sequence is obtained from the fixed point of the 2-uniform morphism a → ab, b → ac, c → db, d → dc followed by the coding a,b → 0, c,d → 1.
The regular paperfolding sequence is obtained from the fixed point of the 2-uniform morphism a → ab, b → cb, c → ad, d → cd followed by the coding a,b → 0, c,d → 1.
D0L system
A D0L system (deterministic context-free Lindenmayer system) is given by a word w of the free monoid A∗ on an alphabet A together with a morphism σ prolongable at w. The system generates the infinite D0L word ω = limn→∞ σn(w). Purely morphic words are D0L words but not conversely. However, if ω = uν is an infinite D0L word with an initial segment u of l |
https://en.wikipedia.org/wiki/Human%20skeleton | The human skeleton is the internal framework of the human body. It is composed of around 270 bones at birth – this total decreases to around 206 bones by adulthood after some bones get fused together. The bone mass in the skeleton makes up about 14% of the total body weight (ca. 10–11 kg for an average person) and reaches maximum mass between the ages of 25 and 30. The human skeleton can be divided into the axial skeleton and the appendicular skeleton. The axial skeleton is formed by the vertebral column, the rib cage, the skull and other associated bones. The appendicular skeleton, which is attached to the axial skeleton, is formed by the shoulder girdle, the pelvic girdle and the bones of the upper and lower limbs.
The human skeleton performs six major functions: support, movement, protection, production of blood cells, storage of minerals, and endocrine regulation.
The human skeleton is not as sexually dimorphic as that of many other primate species, but subtle differences between sexes in the morphology of the skull, dentition, long bones, and pelvis exist. In general, female skeletal elements tend to be smaller and less robust than corresponding male elements within a given population. The human female pelvis is also different from that of males in order to facilitate childbirth. Unlike most primates, human males do not have penile bones.
Divisions
Axial
The axial skeleton (80 bones) is formed by the vertebral column (32–34 bones; the number of the vertebrae differs from human to human as the lower 2 parts, sacral and coccygeal bone may vary in length), a part of the rib cage (12 pairs of ribs and the sternum), and the skull (22 bones and 7 associated bones).
The upright posture of humans is maintained by the axial skeleton, which transmits the weight from the head, the trunk, and the upper extremities down to the lower extremities at the hip joints. The bones of the spine are supported by many ligaments. The erector spinae muscles are also supporting an |
https://en.wikipedia.org/wiki/Salicide | The term salicide refers to a technology used in the microelectronics industry used to form electrical contacts between the semiconductor device and the supporting interconnect structure. The salicide process involves the reaction of a metal thin film with silicon in the active regions of the device, ultimately forming a metal silicide contact through a series of annealing and/or etch processes. The term "salicide" is a compaction of the phrase self-aligned silicide. The description "self-aligned" suggests that the contact formation does not require photolithography patterning processes, as opposed to a non-aligned technology such as polycide.
The term salicide is also used to refer to the metal silicide formed by the contact formation process, such as "titanium salicide", although this usage is inconsistent with accepted naming conventions in chemistry.
Contact formation
The salicide process begins with deposition of a thin transition metal layer over fully formed and patterned semiconductor devices (e.g. transistors). The wafer is heated, allowing the transition metal to react with exposed silicon in the active regions of the semiconductor device (e.g., source, drain, gate) forming a low-resistance transition metal silicide. The transition metal does not react with the silicon dioxide nor the silicon nitride insulators present on the wafer. Following the reaction, any remaining transition metal is removed by chemical etching, leaving silicide contacts in only the active regions of the device. A fully integrable manufacturing process may be more complex, involving additional anneals, surface treatments, or etch processes.
Chemistry
Typical transition metals used or considered for use in salicide technology include titanium, cobalt, nickel, platinum, and tungsten. One key challenge in developing a salicide process is controlling the specific phase (compound) formed by the metal-silicon reaction. Cobalt, for example, may react with silicon to form Co2Si, |
https://en.wikipedia.org/wiki/Oxidase%20test | The oxidase test is used to determine whether an organism possesses the cytochrome c oxidase enzyme. The test is used as an aid for the differentiation of Neisseria, Moraxella, Campylobacter and Pasteurella species (oxidase positive). It is also used to differentiate pseudomonads from related species.
Classification
Strains may be either oxidase-positive (OX+) or oxidase-negative (OX-).
OX+
OX+ normally means the bacterium contains cytochrome c oxidase (also known as Complex IV) and can therefore use oxygen for energy production by converting O2 to H2O2 or H2O with an electron transfer chain.
The Pseudomonadaceae are typically OX+.
The Gram-negative diplococci Neisseria and Moraxella are oxidase-positive.
Many Gram-negative, spiral curved rods are also oxidase-positive, which includes Helicobacter pylori, Vibrio cholerae, and Campylobacter jejuni.
Oxidase variable
Legionella pneumophila may be oxidase-positive.
OX−
OX− normally means the bacterium does not contain cytochrome c oxidase and, therefore, either cannot use oxygen for energy production with an electron transfer chain or employs a different cytochrome for transferring electrons to oxygen.
Enterobacteriaceae are typically OX−.
Mechanism
The test uses disks impregnated with a reagent such as N,N,N′,N′-tetramethyl-p-phenylenediamine, TMPD (or N,N-dimethyl-p-phenylenediamine, DMPD, which is also a redox indicator). The reagent is a dark-blue to maroon color when oxidized, and colorless when reduced. Oxidase-positive bacteria possess cytochrome oxidase or indophenol oxidase (an iron-containing hemoprotein). These both catalyze the transport of electrons from donor compounds (NADH) to electron acceptors (usually oxygen). The test reagent TMPD acts as an artificial electron donor for the enzyme oxidase. The oxidized reagent forms the colored compound indophenol blue. The cytochrome system is usually only present in aerobic organisms that are capable of using oxygen as the terminal electron acceptor. Th |
https://en.wikipedia.org/wiki/EcoSim | EcoSim is an individual-based predator-prey ecosystem simulation in which agents can evolve. It has been designed to investigate several broad ecological questions, as well as long-term evolutionary patterns and processes such as speciation and macroevolution. EcoSim has been designed by Robin Gras at the University of Windsor in 2009 and it is still currently used for research in his Bioinformatics and Ecosystem Simulation Lab.
Main concepts
The agents have a behavior model which allows the evolutionary process to modify the behaviors of the predators and prey. Furthermore, there is a speciation mechanism which allows to study global patterns as well as species-specific patterns. In EcoSim, an individual's genomic data codes for its behavioral model and is represented by a fuzzy cognitive map (FCM). The FCM contains sensory concepts such as foodClose or predatorClose, internal states such as fear or hunger, and motor concepts such as escape or reproduce. The FCM is represented as an array of floating-point values which represent the extent to which one concept influences another. For example, it would be expected that the sensory concept predatorClose would positively affect the internal concept fear, which would then positively affect the escape motor concept. These relationships among concepts evolve over time, sometimes giving a new meaning to a concept. Furthermore, the FCM is heritable, meaning that a new agent is given an FCM which is a combination of that of its parents with possible mutations.
EcoSim subscribes to the “genotypic cluster” definition of a species. Speciation has been implemented using a 2-means clustering algorithm technique designed to allow the splitting of an existing species into two species, by clustering the individuals that initially belonged to the first species into one of the new two species, each one of them containing the agents that are mutually the most similar. Since EcoSim has the capacity to allow speciation events to occu |
https://en.wikipedia.org/wiki/Lyman%E2%80%93Werner%20photons | A Lyman-Werner photon is an ultraviolet photon with a photon energy in the range of 11.2 to 13.6 eV, corresponding to the energy range in which the Lyman and Werner absorption bands of molecular hydrogen (H2) are found. A photon in this energy range, with a frequency that coincides with that of one of the lines in the Lyman or Werner bands, can be absorbed by H2, placing the molecule in an excited electronic state. Radiative decay (that is, decay into photons) from this excited state occurs rapidly, with roughly 15% of these decays occurring into the vibrational continuum of the molecule, resulting in its dissociation. This two-step photodissociation process, known as the Solomon process, is one of the main mechanisms by which molecular hydrogen is destroyed in the interstellar medium.
In reference to the figure shown, Lyman-Werner photons are emitted as described below:
A hydrogen molecule can absorb a far-ultraviolet photon (11.2 eV < energy of the photon < 13.6 eV) and make a transition from the ground electronic state X to excited state B (Lyman) or C (Werner).
Radiative decay occurs rapidly.
10–15% of the decays occur into the vibrational continuum. This means that the hydrogen molecule has dissociated.
Photo-dissociation fragments carry away some of the photon energy as kinetic energy, heating the gas.
Rest of the decays are either radiative decay (infrared emission) or collisional, which ultimately end up heating the gas. |
https://en.wikipedia.org/wiki/Symbiotic%20bacteria | Symbiotic bacteria are bacteria living in symbiosis with another organism or each other. For example, rhizobia living in root nodules of legumes provide nitrogen fixing activity for these plants.
Types of symbiosis
Types of symbiotic relationships are mutualism, commensalism, parasitism, and amensalism.
Endosymbiosis
Endosymbionts live inside other organisms whether that be in their bodies or cells. The theory of endosymbiosis, as known as symbiogenesis, provides an explanation for the evolution of eukaryotic organisms. According to the theory of endosymbiosis for the origin of eukaryotic cells, scientists believe that eukaryotes originated from the relationship between two or more prokaryotic cells approximately 2.7 billion years ago. It is suggested that specifically ancestors of mitochondria and chloroplasts entered into an endosymbiotic relationship with another prokaryotic cell, eventually evolving into the eukaryotic cells that people are familiar with today.
Ectosymbiosis
Ectosymbiosis is defined as a symbiotic relationship in which one organism lives on the outside surface of a different organism. For instance, barnacles on whales is an example of an ectosymbiotic relationship where the whale provides the barnacle with a home, a ride, and access to food. The whale is not harmed, but it also does not receive any benefits so this is also an example of commensalism. An example of ectosymbiotic bacteria is cutibacterium acnes. These bacteria are involved in a symbiotic relationship with humans on whose skin they live. Cutibacterium acnes can cause acne when the skin becomes too oily, but they also reduce the skin's susceptibility to skin diseases caused by oxidative stress.
Symbiotic relationships
Certain plants establish a symbiotic relationship with bacteria, enabling them to produce nodules that facilitate the conversion of atmospheric nitrogen to ammonia. In this connection, cytokinins have been found to play a role in the development of root fixing n |
https://en.wikipedia.org/wiki/Information-centric%20networking%20caching%20policies | In computing, cache algorithms (also frequently called cache replacement algorithms or cache replacement policies) are optimizing instructionsor algorithmsthat a computer program or a hardware-maintained structure can follow in order to manage a cache of information stored on the computer. When the cache is full, the algorithm must choose which items to discard to make room for the new ones. Due to the inherent caching capability of nodes in Information-centric networking ICN, the ICN can be viewed as a loosely connect network of caches, which has unique requirements of Caching policies. Unlike proxy servers, in Information-centric networking the cache is a network level solution. Therefore, it has rapidly changing cache states and higher request arrival rates; moreover, smaller cache sizes further impose different kind of requirements on the content eviction policies. In particular, eviction policies for Information-centric networking should be fast and lightweight. Various cache replication and eviction schemes for different Information-centric networking architectures and applications are proposed.
Policies
Time aware least recently used (TLRU)
The Time aware Least Recently Used (TLRU) is a variant of LRU designed for the situation where the stored contents in cache have a valid life time. The algorithm is suitable in network cache applications, such as information-centric networking (ICN), content delivery networks (CDNs) and distributed networks in general. TLRU introduces a new term: TTU (Time to Use). TTU is a time stamp of a content/page which stipulates the usability time for the content based on the locality of the content and the content publisher announcement. Owing to this locality based time stamp, TTU provides more control to the local administrator to regulate in network storage.
In the TLRU algorithm, when a piece of content arrives, a cache node calculates the local TTU value based on the TTU value assigned by the content publisher. The local TTU |
https://en.wikipedia.org/wiki/Abnormal%20urine%20color | Normally, human urine color is straw-yellow. Urine color other than straw-yellow sometimes reflects an abnormality—an underlying pathological condition—in human beings.
Signs and symptoms
The signs and symptoms of abnormal urine color are shown as follows:
Unexplained urine color other than straw-yellow has continued for a long time.
Once observe blood in urine.
Clear, dark-brown urine.
Risk factors of clinical abnormal urine color include elderly age, strenuous exercise, and family history of related diagnosis.
Cause
Infection, disease, medicines, or food can all affect urine color temporarily. For instance, cloudy or milky urine usually accompanied by bad smell possibly indicates urinary tract infection, excessive discharge of crystals, fat, white blood cells, red blood cells, or mucus.
Dark urine that looks brown but clear might be a warning sign of a serious liver disease like hepatitis or cirrhosis. In which, an excess of bilirubin being discharged through urine.
In case the urine looks in pink, red, or lighter brown is generally caused by beets, blackberries, certain food colorings, hemolytic anemia, renal impairment, urinary tract infection, medication, porphyria, intra-abdominal bleeding, vaginal bleeding, neoplasm located in either bladder or kidneys pathways.
If urine looks dark yellow or similar to orange color, the causative factors might be recent uses of a riboflavin-containing dietary supplement, carotene, phenazopyridine, rifampin, warfarin or laxative.
The causation or contributing factors of the urine color change to green or blue are those artificial colors seen in foods and drugs, or bilirubin medicines such as methylene blue, and urinary tract infections.
Diagnosis
Doctor may prescribe some tests to help get the full picture of the situation, such as blood tests, liver function tests, ultrasound for kidneys and bladder, urinalysis, urine culture for infection, and cystoscopy.
Doctor may also ask for the medical history to collect i |
https://en.wikipedia.org/wiki/Functional%20extinction | Functional extinction is the extinction of a species or other taxon such that:
It disappears from the fossil record, or historic reports of its existence cease;
The reduced population no longer plays a significant role in ecosystem function; or
The population is no longer viable. There are no individuals able to reproduce, or the small population of breeding individuals will not be able to sustain itself due to inbreeding depression and genetic drift, which leads to a loss of fitness.
In plant populations, self-incompatibility mechanisms may cause related plant specimens to be incompatible, which may lead to functional extinction if an entire population becomes self-incompatible. This does not occur in larger populations.
In polygynous populations, where only a few males leave offspring, there is a much smaller reproducing population than if all viable males were considered. Furthermore, the successful males act as a genetic bottleneck, leading to more rapid genetic drift or inbreeding problems in small populations.
Functionally extinct species in modern times
Baiji dolphin
Northern white rhinoceros
Ivory-billed woodpecker
Christmas Island shrew
Yangtze giant softshell turtle
South China Tiger
Bornean rhinoceros
North Atlantic right whale
Vaquita
Fernandina Island tortoise
On May 10, 2019, the Australian Koala Foundation issued a press release that opened with the sentence "The Australian Koala Foundation (AKF) believes Koalas may be functionally extinct in the entire landscape of Australia." The press release was reported on by multiple news agencies around the world, with most repeating the AKF's statement. Despite this, koalas are not currently considered functionally extinct; while their population has decreased, the IUCN Red List lists them only as "Vulnerable". The AKF's press release was released on the eve of the 2019 elections in Australia, where topics such as climate change were major issues.
Distinct animal populations can also become functionally |
https://en.wikipedia.org/wiki/Jen%C5%91%20Sz%C3%A9p | Jenő Szép (13 January 1920 – 18 October 2004) was a Hungarian mathematician and professor at the University of Economics, Budapest (now Corvinus University). His main research interests were group theory and game theory. He was a founder of the journal Pure Mathematics and Applications (PUMA).
The Zappa–Szép product in group theory is named after him and Guido Zappa.
Biography
Jenő Szép's parents were Pál Szép and Arabella Liebert. His wife Gabriella Tésy (1919–2015) was also a mathematician. They had four children: Gabriella (1948), Katalin (1950), Zsófia (1952), and Jenő (1957).
Szép graduated from Miklós Zrínyi Real High School in Budapest in 1938. He later attended Pázmány Péter University and obtained a teacher's diploma in mathematics and physics in 1943, as well as a doctorate in humanities in 1946. He was an intern (1941–1943) and assistant professor (1943–1946) at the Pázmány Péter University Institute of Mathematics, alongside Lipót Fejér and Béla Kerékjártó. He also taught at the Budapest Civic School Teacher Training College (1946–1949).
In 1952, Szép was awarded the Candidate of Mathematical Sciences for his advanced activities and he received his doctorate in 1957 from the Hungarian Academy of Sciences. From 1949 to 1961, he was the head of the Department of Mathematics at the Szeged Teacher Training College.
In February 1961, Szép joined the Department of Mathematics at Corvinus University of Budapest (then the Karl Marx University of Economics). He worked as head of the department from then until 1987 and under his leadership the department became an internationally acknowledged research institute. He was appointed as director of the Institute of Mathematics and Computer Science in 1976 and stayed in this position until his departure in 1987.
In 1990, Szép founded the international scientific journal Pure Mathematics and Applications (PUMA) with professor Franco Migliorini of Università degli Studi di Siena. He was the editor-in-chief of the |
https://en.wikipedia.org/wiki/Dry%20loop | A dry loop is an unconditioned leased pair of telephone line from a telephone company. The pair does not provide dial tone or battery (continuous electric potential), as opposed to a wet pair, a line usually without dial tone but with battery.
A dry pair was originally used with a security system but more recently may also be used with digital subscriber line (DSL) service or an Ethernet extender to connect two locations, as opposed to a costlier means such as a Frame Relay. The pair in many cases goes through the local telephone exchange.
Wet pair naming comes from the battery used to sustain the loop, which was made from wet cells.
Many carriers market dry loops to independent DSL providers as a BANA for basic analog loop or in some locales PANA for plain analog loop, OPX (off-premises extension) line, paging circuit, or finally LADS (local area data service).
Local availability
In the United States, these circuits typically incur a monthly recurring charge of $3.00 per ¼ mile (approximately), plus an additional handling fee of around ($5–10).
In Canada, a CRTC ruling of 21 July 2003 requires telcos (such as Bell Canada) permit dry loop and some companies do provide this service. Naked DSL is currently provided by third-party DSL (digital subscriber line) vendors in the provinces of Ontario and Quebec, but incurs an additional dry loop fee (often $5 or more monthly, depending on the distance from the exchange). There is not yet widespread adoption, as this extra fee often renders dry-loop DSL more costly than comparable cable modem service in most locations. A Bell Canada "dry loop" DSL connection does supply battery, but the underlying phone line is non-functional except to call 958-ANAC, 9-1-1 or the 310-BELL telco business office.
See also
Current loop
Local-loop unbundling
Naked DSL
Permitted attached private lines |
https://en.wikipedia.org/wiki/Photoelectrochemical%20process | Photoelectrochemical processes are processes in photoelectrochemistry; they usually involve transforming light into other forms of energy. These processes apply to photochemistry, optically pumped lasers, sensitized solar cells, luminescence, and photochromism.
Electron excitation
Electron excitation is the movement of an electron to a higher energy state. This can either be done by photoexcitation (PE), where the original electron absorbs the photon and gains all the photon's energy or by electrical excitation (EE), where the original electron absorbs the energy of another, energetic electron. Within a semiconductor crystal lattice, thermal excitation is a process where lattice vibrations provide enough energy to move electrons to a higher energy band. When an excited electron falls back to a lower energy state again, it is called electron relaxation. This can be done by radiation of a photon or giving the energy to a third spectator particle as well.
In physics there is a specific technical definition for energy level which is often associated with an atom being excited to an excited state. The excited state, in general, is in relation to the ground state, where the excited state is at a higher energy level than the ground state.
Photoexcitation
Photoexcitation is the mechanism of electron excitation by photon absorption, when the energy of the photon is too low to cause photoionization. The absorption of the photon takes place in accordance with Planck's quantum theory.
Photoexcitation plays role in photoisomerization. Photoexcitation is exploited in dye-sensitized solar cells, photochemistry, luminescence, optically pumped lasers, and in some photochromic applications.
Photoisomerization
In chemistry, photoisomerization is molecular behavior in which structural change between isomers is caused by photoexcitation. Both reversible and irreversible photoisomerization reactions exist. However, the word "photoisomerization" usually indicates a reversible proc |
https://en.wikipedia.org/wiki/Mina%20Teicher | Mina Teicher is an Israeli mathematician at Bar-Ilan University, specializing in algebraic geometry.
Teicher earned bachelor's, masters, and doctoral degrees from Tel Aviv University in 1974, 1976, and 1981 respectively. Her dissertation, Birational Transformation Between 4-folds, was supervised by Ilya Piatetski-Shapiro.
Since 1999, she has directed the Emmy Noether Research Institute for Mathematics at Bar-Ilan University.
In 2001–2002 she was the inaugural Emmy Noether Visiting professor at the University of Göttingen, where she lectured about braid groups.
She has held many leadership roles in academia and science, including serving from 2005 to 2007 as chief scientist at Israel's Ministry of Science and Technology, and chairing the board of governors of the United States – Israel Binational Science Foundation from 2012 to 2013. |
https://en.wikipedia.org/wiki/Transdichotomous%20model | In computational complexity theory, and more specifically in the analysis of algorithms with integer data, the transdichotomous model is a variation of the random-access machine in which the machine word size is assumed to match the problem size. The model was proposed by Michael Fredman and Dan Willard, who chose its name "because the dichotomy between the machine model and the problem size is crossed in a reasonable manner."
In a problem such as integer sorting in which there are integers to be sorted, the transdichotomous model assumes that each integer may be stored in a single word of computer memory, that operations on single words take constant time per operation, and that the number of bits that can be stored in a single word is at least . The goal of complexity analysis in this model is to find time bounds that depend only on and not on the actual size of the input values or the machine words. In modeling integer computation, it is necessary to assume that machine words are limited in size, because models with unlimited precision are unreasonably powerful (able to solve PSPACE-complete problems in polynomial time). The transdichotomous model makes a minimal assumption of this type: that there is some limit, and that the limit is large enough to allow random-access indexing into the input data.
As well as its application to integer sorting, the transdichotomous model has also been applied to the design of priority queues and to problems in computational geometry and graph algorithms.
See also
Word RAM
Cell-probe model |
https://en.wikipedia.org/wiki/Common%20Indexing%20Protocol | The Common Indexing Protocol (CIP) was an attempt in the IETF working group FIND during the mid-1990s to define a protocol for exchanging index information between directory services.
In the X.500 Directory model, searches scoped near the root of the tree (e.g. at a particular country) were problematic to implement, as potentially hundreds or thousands of directory servers would need to be contacted
in order to handle that query.
The indexes contained summaries or subsets of information about individuals and organizations represented in a white pages schema. By merging subsets of information from multiple sources, it was hoped that an index server holding that subset could be able to process a query more efficiently by chaining it only to some of the sources: those sources which did not hold information would not be contacted. For example, if a server holding the base entry for a particular country were provided with a list of names of all the people in all the entries in that country subtree, then that server would be able to process a query searching for a person with
a particular name by only chaining it to those servers which held data about such a person.
The protocol evolved from earlier work developing WHOIS++, and was intended to be capable of interconnecting
services from both the evolving WHOIS and LDAP activities.
This protocol has not seen much recent deployment, as WHOIS and LDAP environments have followed separate evolution paths. WHOIS deployments are typically in domain name registrars, and its data management issues have been addressed through specifications for domain name registry interconnection such as CRISP. In contrast, enterprises that manage employee, customer or student identity data in an LDAP directory have looked to federation protocols for interconnection between organizations.
RFCs
The Architecture of the Common Indexing Protocol (CIP)
MIME Object Definitions for the Common Indexing Protocol (CIP)
CIP Transport Pro |
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