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Standard normal table Cumulative (less than Z) Standard_normal_table > Table examples > Cumulative (less than Z) This table gives a probability that a statistic is less than Z (i.e. between negative infinity and Z).
LM hash Security weaknesses LAN_Manager > Security weaknesses The hash value is sent to network servers without salting, making it susceptible to man-in-the-middle attacks such as replay the hash. Without salt, time–memory tradeoff pre-computed dictionary attacks, such as a rainbow table, are feasible. In 2003, Ophcrack, an implementation of the rainbow table technique, was published. It specifically targets the weaknesses of LM encryption, and includes pre-computed data sufficient to crack virtually all alphanumeric LM hashes in a few seconds. Many cracking tools, such as RainbowCrack, Hashcat, L0phtCrack and Cain, now incorporate similar attacks and make cracking of LM hashes fast and trivial.
Kepler-22b Limits on satellites Kepler-22b > Habitability > Limits on satellites The Hunt for Exomoons with Kepler (HEK) project has studied the Kepler photometry of the planet, to find any evidence of transit timing and duration variations that may be caused by an orbiting satellite. Such variations were not found, so ruling out the existence of any satellites of Kepler-22b with a mass greater than 0.54 Earth masses.
Darboux function Darboux function Darboux's_theorem_(analysis) > Darboux function This implies in particular that the class of Darboux functions is not closed under addition. A strongly Darboux function is one for which the image of every (non-empty) open interval is the whole real line. The Conway base 13 function is again an example.
Limits and colimits Summary Limit_(category_theory) In category theory, a branch of mathematics, the abstract notion of a limit captures the essential properties of universal constructions such as products, pullbacks and inverse limits. The dual notion of a colimit generalizes constructions such as disjoint unions, direct sums, coproducts, pushouts and direct limits. Limits and colimits, like the strongly related notions of universal properties and adjoint functors, exist at a high level of abstraction. In order to understand them, it is helpful to first study the specific examples these concepts are meant to generalize.
Subunit vaccine Future directions Subunit_vaccine > Future directions Recombinant subunit vaccines are used in development for tuberculosis, dengue fever, soil-transmitted helminths, feline leukaemia and COVID-19.Subunit vaccines are not only considered effective for SARS-COV-2, but also as candidates for evolving immunizations against malaria, tetanus, salmonella enterica, and other diseases.
Binary matrix Logical vectors Binary_matrix > Logical vectors A reordering of the rows and columns of such a matrix can assemble all the ones into a rectangular part of the matrix.Let h be the vector of all ones. Then if v is an arbitrary logical vector, the relation R = v hT has constant rows determined by v. In the calculus of relations such an R is called a vector. A particular instance is the universal relation h h T {\displaystyle hh^{\operatorname {T} }} .
Reaction chemistry Kinetics Metal-acid_reaction > Kinetics This is particularly true for reactions involving radicals.Several theories allow calculating the reaction rates at the molecular level. This field is referred to as reaction dynamics.
Percent sign Evolution Percentage_sign > Evolution At some point, a scribe used the abbreviation "pc" with a tiny loop or circle (depicting the ending -o used in Italian ordinals, as in primo, secondo, etc.; it is analogous to the English "-th" as in "25th"). This appears in some additional pages of a 1425 text which were probably added around 1435. This is shown below (source, Rara Arithmetica p.
Person–environment fit Supplementary fit Person–environment_fit > Contributing theories > Supplementary fit Supplementary fit refers to the similarity between characteristics of a person and characteristics of the environment, or other persons within the environment. Based on compatibility that derives from similarity, a person fits into some environmental context because he/she supplements, embellishes, or possesses characteristics that are similar to other individuals in the environment. People perceive themselves as fitting in because they are like or similar to other people possessing the same characteristics. Therefore, it is essentially a model of a person-person fit.
Microcirculation Regulation Microcirculation > Function > Regulation As a consequence, microcirculation blood flow remains constant despite changes in systemic blood pressure. This mechanism is present in all tissues and organs of the human body.
Maclaurin series Second example Taylor_polynomials > Calculation of Taylor series > Second example + x 3 3 ! + x 4 4 ! + ⋯ {\displaystyle e^{x}=\sum _{n=0}^{\infty }{\frac {x^{n}}{n!
Gibbs random field Statistical physics Gibbs_measure > Statistical physics If the Hamiltonian possesses a symmetry, then a unique (i.e. ergodic) Gibbs measure will necessarily be invariant under the symmetry. But in the case of multiple (i.e. nonergodic) Gibbs measures, the pure states are typically not invariant under the Hamiltonian's symmetry. For example, in the infinite ferromagnetic Ising model below the critical temperature, there are two pure states, the "mostly-up" and "mostly-down" states, which are interchanged under the model's Z 2 {\displaystyle \mathbb {Z} _{2}} symmetry.
Glossary of mechanical engineering C Glossary_of_mechanical_engineering > C The individual components remain separate and distinct within the finished structure, differentiating composites from mixtures and solid solutions. Compression ratio – The static compression ratio, (symbol ε {\displaystyle \varepsilon } ), of an internal combustion engine or external combustion engine is a value that represents the ratio of the volume of its combustion chamber from its largest capacity to its smallest capacity. It is a fundamental specification for many common combustion engines.
Heads-Up Display Design factors Target_blip > Design factors The HUD image is viewable by one or both eyes, depending on technical and budget limitations in the design process. Modern expectations are that both eyes view the same image, in other words a "binocular Field of View (FOV)". Collimation – The projected image is collimated which makes the light rays parallel.
Bimolecular nucleophilic substitution Nucleophile Bimolecular_nucleophilic_substitution > Factors affecting the rate of the reaction > Nucleophile Like the substrate, steric hindrance affects the nucleophile's strength. The methoxide anion, for example, is both a strong base and nucleophile because it is a methyl nucleophile, and is thus very much unhindered. tert-Butoxide, on the other hand, is a strong base, but a poor nucleophile, because of its three methyl groups hindering its approach to the carbon. Nucleophile strength is also affected by charge and electronegativity: nucleophilicity increases with increasing negative charge and decreasing electronegativity.
Microsoft SQL Server Data retrieval and programmability Microsoft_SQL_Server > Data retrieval and programmability While a concurrent execution is more costly in terms of total processor time, because the execution is actually split to different processors might mean it will execute faster. Once a query plan is generated for a query, it is temporarily cached. For further invocations of the same query, the cached plan is used.
Information flow (information theory) Declassification Information_flow_(information_theory) > Declassification As shown previously, non-interference policy is too strict for use in most real-world applications. Therefore, several approaches to allow controlled releases of information have been devised. Such approaches are called information declassification. Robust declassification requires that an active attacker may not manipulate the system in order to learn more secrets than what passive attackers already know.Information declassification constructs can be classified in four orthogonal dimensions: What information is released, Who is authorized to access the information, Where the information is released, and When is the information released.
Hydrogen potassium ATPase Enzyme mechanism and activity Hydrogen_potassium_ATPase > Enzyme mechanism and activity The hydrogen potassium ATPase is activated indirectly by gastrin that causes ECL cells to release histamine. The histamine binds to H2 receptors on the parietal cell, activating a cAMP-dependent pathway which causes the enzyme to move from the cytoplasmic tubular membranes to deeply folded canaliculi of the stimulated parietal cell. Once localized, the enzyme alternates between two conformations, E1 and E2, to transport ions across the membrane.
Bioluminescence Communication Bioluminescence > Uses in nature > Communication Communication by light emission between the zooids enables coordination of colony effort, for example in swimming where each zooid provides part of the propulsive force.Some bioluminous bacteria infect nematodes that parasitize Lepidoptera larvae. When these caterpillars die, their luminosity may attract predators to the dead insect thus assisting in the dispersal of both bacteria and nematodes.
Bond-line formula Contemporary graphical conventions Skeletal_model > The skeleton > Contemporary graphical conventions Since skeletal structures were introduced in the latter half of the 19th century, their appearance has undergone considerable evolution. The graphical conventions in use today date to the 1980s. Thanks to the adoption of the ChemDraw software package as a de facto industry standard (by American Chemical Society, Royal Society of Chemistry, and Gesellschaft Deutscher Chemiker publications, for instance), these conventions have been nearly universal in the chemical literature since the late 1990s. A few minor conventional variations, especially with respect to the use of stereobonds, continue to exist as a result of differing US, UK and European practice, or as a matter of personal preference. As another minor variation between authors, formal charges can be shown with the plus or minus sign in a circle (⊕, ⊖) or without the circle. The set of conventions that are followed by most authors is given below, along with illustrative examples.
History of aerodynamics Developments in aviation History_of_aerodynamics > Developments in aviation Chanute's book provided a great service to those interested in aerodynamics and flying machines. With the information contained in Chanute's book, the personal assistance of Chanute himself, and research carried out in their own wind tunnel, the Wright brothers gained enough knowledge of aerodynamics to fly the first powered aircraft on December 17, 1903. The Wright brothers' flight confirmed or disproved a number of aerodynamics theories.
Non-exact solutions in general relativity Summary Non-exact_solutions_in_general_relativity Non-exact solutions in general relativity are solutions of Albert Einstein's field equations of general relativity which hold only approximately. These solutions are typically found by treating the gravitational field, g {\displaystyle g} , as a background space-time, γ {\displaystyle \gamma } , (which is usually an exact solution) plus some small perturbation, h {\displaystyle h} . Then one is able to solve the Einstein field equations as a series in h {\displaystyle h} , dropping higher order terms for simplicity. A common example of this method results in the linearised Einstein field equations. In this case we expand the full space-time metric about the flat Minkowski metric, η μ ν {\displaystyle \eta _{\mu \nu }}: g μ ν = η μ ν + h μ ν + O ( h 2 ) {\displaystyle g_{\mu \nu }=\eta _{\mu \nu }+h_{\mu \nu }+{\mathcal {O}}(h^{2})} ,and dropping all terms which are of second or higher order in h {\displaystyle h} .
Internet of Autonomous Things Summary Internet_of_Autonomous_Things AuT technologies share many common traits, which justify the common notation. They are all based on recent breakthroughs in the domains of (deep) machine learning and artificial intelligence. They all require extensive and prompt regulatory developments to specify the requirements from them and to license and manage their deployment (see the further reading below).
World lines World lines in general relativity World_lines > World lines in general relativity However, a lightcone is not necessarily inclined at 45 degrees to the time axis. However, this is an artifact of the chosen coordinate system, and reflects the coordinate freedom (diffeomorphism invariance) of general relativity.
Succinyl coenzyme A synthetase Summary Succinyl-CoA_synthetase Succinyl coenzyme A synthetase (SCS, also known as succinyl-CoA synthetase or succinate thiokinase or succinate-CoA ligase) is an enzyme that catalyzes the reversible reaction of succinyl-CoA to succinate. The enzyme facilitates the coupling of this reaction to the formation of a nucleoside triphosphate molecule (either GTP or ATP) from an inorganic phosphate molecule and a nucleoside diphosphate molecule (either GDP or ADP). It plays a key role as one of the catalysts involved in the citric acid cycle, a central pathway in cellular metabolism, and it is located within the mitochondrial matrix of a cell.
Noise-equivalent bandwidth Summary Spectral_leakage For Fourier transform purposes, sampling is modeled as a product between s(t) and a Dirac comb function. The spectrum of a product is the convolution between S(f) and another function, which inevitably creates the new frequency components.
Protein molecule Biochemistry Cellular_protein > Biochemistry The other two dihedral angles in the peptide bond determine the local shape assumed by the protein backbone. : 31 The end with a free amino group is known as the N-terminus or amino terminus, whereas the end of the protein with a free carboxyl group is known as the C-terminus or carboxy terminus (the sequence of the protein is written from N-terminus to C-terminus, from left to right). The words protein, polypeptide, and peptide are a little ambiguous and can overlap in meaning.
Consistent Histories Interpretation Consistent_Histories > Interpretation The consistent histories approach can be interpreted as a way of understanding which sets of classical questions can be consistently asked of a single quantum system, and which sets of questions are fundamentally inconsistent, and thus meaningless when asked together. It thus becomes possible to demonstrate formally why it is that the questions which Einstein, Podolsky and Rosen assumed could be asked together, of a single quantum system, simply cannot be asked together. On the other hand, it also becomes possible to demonstrate that classical, logical reasoning often does apply, even to quantum experiments – but we can now be mathematically exact about the limits of classical logic.
Zeaxanthin epoxidase Summary Zeaxanthin_epoxidase Zeaxanthin epoxidase (EC 1.14.13.90, Zea-epoxidase) is an enzyme with systematic name zeaxanthin,NAD(P)H:oxygen oxidoreductase. This enzyme catalyses the following chemical reaction zeaxanthin + 2 NAD(P)H + 2 H+ + 2 O2 ⇌ {\displaystyle \rightleftharpoons } violaxanthin + 2 NAD(P)+ + 2 H2O (overall reaction) (1a) zeaxanthin + NAD(P)H + H+ + O2 ⇌ {\displaystyle \rightleftharpoons } antheraxanthin + NAD(P)+ + H2O (1b) antheraxanthin + NAD(P)H + H+ + O2 ⇌ {\displaystyle \rightleftharpoons } violaxanthin + NAD(P)+ + H2OZeaxanthin epoxidase is a flavoprotein (FAD) that is active under conditions of low light.
Motor coordination Intra-limb Motor_coordination > Types of Motor Coordination > Intra-limb Importantly, control strategies for goal directed movement are task-dependent. This was shown by testing two different conditions: (1) subjects moved cursor in the hand to the target and (2) subjects move their free hand to the target. Each condition showed different trajectories: (1) straight path and (2) curved path.
Difference algebra Summary Difference_algebra Difference algebra is a branch of mathematics concerned with the study of difference (or functional) equations from the algebraic point of view. Difference algebra is analogous to differential algebra but concerned with difference equations rather than differential equations. As an independent subject it was initiated by Joseph Ritt and his student Richard Cohn.
Darier's disease Genetics Darier's_disease > Genetics Significant variability in disease severity between members of the same family carrying the same mutation was also reported by this study, suggesting that genetic modifiers contribute to the phenotypic penetrance of certain mutations.The mutation is inherited in an autosomal dominant pattern. This means that only one allele needs to be mutated in order to express the trait. This also means that someone who is born to one parent with DAR has a 50% chance of inheriting the mutant allele and having the disease.
Vinyl polymer Production Vinyl_polymer > Production Still others (poystyrene) are produced using anionic initiators such as butyl lithium. An exception from the usual rules, polyvinyl alcohol, (CH2CHOH)n, is produced by hydrolysis of polyvinyl acetate. Vinyl alcohol is not sufficiently stable to undergo polymerization.
Quantum indeterminism Other examples of indeterminacy Quantum_indeterminism > Measurement > Other examples of indeterminacy Quantum indeterminacy can also be illustrated in terms of a particle with a definitely measured momentum for which there must be a fundamental limit to how precisely its location can be specified. This quantum uncertainty principle can be expressed in terms of other variables, for example, a particle with a definitely measured energy has a fundamental limit to how precisely one can specify how long it will have that energy. The units involved in quantum uncertainty are on the order of Planck's constant (defined to be 6.62607015×10−34 J⋅Hz−1).
Mathematical crystallography Reference literature Crystallography > Reference literature The International Tables for Crystallography is an eight-book series that outlines the standard notations for formatting, describing and testing crystals. The series contains books that covers analysis methods and the mathematical procedures for determining organic structure through x-ray crystallography, electron diffraction, and neutron diffraction. The International tables are focused on procedures, techniques and descriptions and do not list the physical properties of individual crystals themselves. Each book is about 1000 pages and the titles of the books are: Vol A - Space Group Symmetry, Vol A1 - Symmetry Relations Between Space Groups, Vol B - Reciprocal Space, Vol C - Mathematical, Physical, and Chemical Tables, Vol D - Physical Properties of Crystals, Vol E - Subperiodic Groups, Vol F - Crystallography of Biological Macromolecules, and Vol G - Definition and Exchange of Crystallographic Data.
Evolution as fact and theory Theory Evolution_as_fact_and_theory > Evolution, fact and theory > Theory Species inherit traits, which are then passed on to descendants. Evolutionary biologists use systematic methods and test phylogenetic theory to observe and explain changes in and among species over time. These methods include the collection, measurement, observation, and mapping of traits onto evolutionary trees. Phylogenetic theory is used to test the independent distributions of traits and their various forms to provide explanations of observed patterns in relation to their evolutionary history and biology. The neutral theory of molecular evolution is used to study evolution as a null model against which tests for natural selection can be applied.
Time Travel Presentism vs. eternalism Time_Travel > Philosophy > Presentism vs. eternalism "Here-now presentism" attempts to reconcile this by only acknowledging the time and space of a single point; this is unsatisfactory because objects coming and going from the "here-now" alternate between real and unreal, in addition to the lack of a privileged "here-now" that would be the "real" present. "Relativized presentism" acknowledges that there are infinite frames of reference, each of them having a different set of simultaneous events, which makes it impossible to distinguish a single "real" present, and hence either all events in time are real—blurring the difference between presentism and eternalism—or each frame of reference exists in its own reality. Options for presentism in special relativity appear to be exhausted, but Gödel and others suspect presentism may be valid for some forms of general relativity. Generally, the idea of absolute time and space is considered incompatible with general relativity; there is no universal truth about the absolute position of events which occur at different times, and thus no way to determine which point in space at one time is at the universal "same position" at another time, and all coordinate systems are on equal footing as given by the principle of diffeomorphism invariance.
Beta adrenergic receptor kinase carboxyl-terminus Heart Failure Beta_adrenergic_receptor_kinase_carboxyl-terminus > Heart Failure Continuous stimulation of the βARs leads to the activation of βARK1 which phosphorylates βARs to decrease their response to norepinephrine and other catecholamines. βARs are downregulated as a result, decreasing the control over the heart’s rate and force of contraction. A cycle begins as more norepinephrine is produced in an attempt to stimulate the heart to contract.
Prestack Informal definition Prestack > Informal definition A statement like this is independent of choices of canonical identifications mentioned early. The essential image of F ( U ) → F ( { V i → U } ) {\displaystyle F(U)\to F(\{V_{i}\to U\})} consists precisely of effective descent data (just the definition of "effective"). Thus, F is a stack if and only if, for each covering family { V i → U } {\displaystyle \{V_{i}\to U\}} , F ( U ) → F ( { V i → U } ) {\displaystyle F(U)\to F(\{V_{i}\to U\})} is an equivalence of categories. These reformulations of the definitions of prestacks and stacks make intuitive meanings of those concepts very explicit: (1) "fibered category" means one can construct a pullback (2) "prestack in groupoids" additionally means "locally isomorphic" implies "isomorphic" (3) "stack in groupoids" means, in addition to the previous properties, a global object can be constructed from local data subject to cocycle conditions. All these work up to canonical isomorphisms.
Multiprocessing Master/slave multiprocessor system Tightly_coupled_system > Key topics > Processor symmetry > Master/slave multiprocessor system In a master/slave multiprocessor system, the master CPU is in control of the computer and the slave CPU(s) performs assigned tasks. The CPUs can be completely different in terms of speed and architecture. Some (or all) of the CPUs can share a common bus, each can also have a private bus (for private resources), or they may be isolated except for a common communications pathway. Likewise, the CPUs can share common RAM and/or have private RAM that the other processor(s) cannot access.
Bloom (test) Summary Bloom_(test) To perform the Bloom test on gelatin, a 6.67% gelatin solution is kept for 17–18 hours at 10 °C prior to being tested. Various gelatins are categorized as "low Bloom", "medium Bloom", or "high Bloom", but there are not universally defined specific values for these subranges. Gelatin is a biopolymer material composed of polypeptide chains of varying length. The longer the chain, the higher the Bloom number:
Werner Heisenberg Other research publications Werner_Heisenberg > Other research publications — (1950). "On the stability of laminar flow". Proc.
Cache coherency protocols (examples) Cache states Cache_coherency_protocols_(examples) > Snoopy coherency protocol > Cache states data may be stored in more than a cache but the data in memory is not updated (invalid, not clean). Only one cache is the "owner", other caches are set "Valid" (S/V/SC). On bus read request, the data is supplied by the "owner" instead of the memory.
Long-acting beta-adrenoceptor agonist Ultra-LABAs Long-acting_beta_agonist > Ultra-LABAs This second medication in this combination is the synthetic inhaled corticosteroid fluticasone furoate. This product was approved by the FDA in May 2013 as once-daily inhaled therapy for the treatment of chronic obstructive pulmonary disease (COPD) with umeclidinium bromide: Anoro Ellipta. Umeclidinium bromide is a long-acting muscarinic antagonist. This combination was approved by the FDA on December 18, 2013 for the long-term maintenance treatment of COPD. On March 28, 2014, it was approved in European countries and in Russia under the same trade name
Model Based Design Disadvantages Model_Based_Design > Disadvantages The disadvantages of model-based design are fairly well understood this late in development lifecycle of the product and development. One major disadvantage is that the approach taken is a blanket or coverall approach to standard embedded and systems development. Often the time it takes to port between processors and ecosystems can outweigh the temporal value it offers in the simpler lab based implementations.Much of the compilation tool chain is closed source, and prone to fence post errors, and other such common compilation errors that are easily corrected in traditional systems engineering.Design and reuse patterns can lead to implementations of models that are not well suited to that task. Such as implementing a controller for a conveyor belt production facility that uses a thermal sensor, speed sensor, and current sensor.
Bacterial transcription Initiation Bacterial_transcription > Initiation At this point, the holoenzyme is referred to as the closed complex because the DNA is still double stranded (connected by hydrogen bonds). Once the σ-factor binds, the remaining subunits of the polymerase attach to the site. The high concentration of adenine-thymine bonds at the -10 region facilitates the unwinding of the DNA.
Blankenship–Oporowski conjecture Computational complexity Book_embedding > Properties > Computational complexity Finding the book thickness of a graph is NP-hard. This follows from the fact that finding Hamiltonian cycles in maximal planar graphs is NP-complete. In a maximal planar graph, the book thickness is two if and only if a Hamiltonian cycle exists. Therefore, it is also NP-complete to test whether the book thickness of a given maximal planar graph is two.If an ordering of the vertices of a graph along the spine of an embedding is fixed, then a two-page embedding (if it exists) can be found in linear time, as an instance of planarity testing for a graph formed by augmenting the given graph with a cycle connecting the vertices in their spine ordering.
Duplicating machines How digital duplicators work Duplicating_machines > Digital duplicators > How digital duplicators work The paper is fed to the drum, and the ink only comes through the master material where there are holes. A pressure roller presses the paper to the drum and transfers the ink to the paper to form the image. The paper then exits the machine into an exit tray. The ink is still wet.
Mathematical formulations of quantum mechanics Postulates of quantum mechanics Mathematical_formulations_of_quantum_mechanics > Postulates of quantum mechanics (It is possible, to map this Hilbert-space picture to a phase space formulation, invertibly. See below.) The following summary of the mathematical framework of quantum mechanics can be partly traced back to the Dirac–von Neumann axioms.
Modulus of continuity Examples of use Modulus_of_continuity > Examples of use Let f: → R a continuous function. In the proof that f is Riemann integrable, one usually bounds the distance between the upper and lower Riemann sums with respect to the Riemann partition P := {t0, ..., tn} in terms of the modulus of continuity of f and the mesh of the partition P (which is the number \| P \| := max 0 ≤ i < n ( t i + 1 − t i ) {\textstyle \|P\|:=\max _{0\leq i
Dzhanibekov effect Geometric analysis Intermediate_axis_theorem > Geometric analysis During motion, both the energy and angular momentum-squared are conserved, thus we have two conserved quantities:and so for any initial condition ω ( 0 ) {\displaystyle \omega (0)} , the trajectory of ω ( t ) {\displaystyle \omega (t)} must stay on the intersection curve between two ellipsoids defined by This is shown on the animation to the left. By inspecting Euler's equations, we see that ω ( t ) = 0 {\displaystyle \omega (t)=0} implies that two components of ω ( t ) {\displaystyle \omega (t)} are zero—that is, the object is exactly spinning around one of the principal axes. In all other situations, ω ( t ) {\displaystyle \omega (t)} must remain in motion. By Euler's equations, if ω ( t ) {\displaystyle \omega (t)} is a solution, then so is c ω ( c t ) {\displaystyle c\omega (ct)} for any constant c > 0 {\displaystyle c>0} .
Synchronous programming Summary Synchronous_programming A synchronous programming language is a computer programming language optimized for programming reactive systems. Computer systems can be sorted in three main classes: (1) transformational systems that take some inputs, process them, deliver their outputs, and terminate their execution; a typical example is a compiler; (2) interactive systems that interact continuously with their environment, at their own speed; a typical example is the web; and (3) reactive systems that interact continuously with their environment, at a speed imposed by the environment; a typical example is the automatic flight control system of modern airplanes. Reactive systems must therefore react to stimuli from the environment within strict time bounds. For this reason they are often also called real-time systems, and are found often in embedded systems.
Abnormal Psychology Cognitive behavioural therapy (Ellis and Beck) Abnormal_Psychology > Therapies > Cognitive behavioural therapy (Ellis and Beck) When these expectations are not met, it will often result in maladaptive behaviors, such as depression, obsessive compulsions, and anxiety. With CBT, the goal is to change the schemas that are causing the stress in the patients life, and replace them with more realistic ones. Once the negative schemas have been replaced, it will hopefully cause a remission of the patients symptoms.
Snell's Law Explanation Angle_of_refraction > Explanation Snell's law is used to determine the direction of light rays through refractive media with varying indices of refraction. The indices of refraction of the media, labeled n 1 {\displaystyle n_{1}} , n 2 {\displaystyle n_{2}} and so on, are used to represent the factor by which a light ray's speed decreases when traveling through a refractive medium, such as glass or water, as opposed to its velocity in a vacuum. As light passes the border between media, depending upon the relative refractive indices of the two media, the light will either be refracted to a lesser angle, or a greater one. These angles are measured with respect to the normal line, represented perpendicular to the boundary.
Design of quasi-experiments Ethics Quasi-experimental_design > Ethics However, to simply randomize parents to spanking or not spanking categories may not be practical or ethical, because some parents may believe it is morally wrong to spank their children and refuse to participate. Some authors distinguish between a natural experiment and a "quasi-experiment". A natural experiment may approximate random assignment, or involve real randomization not by the experimenters or for the experiment.
ArangoDB Main features ArangoDB > Main features Predictable performance: ArangoDB is written mainly in C++ and manages its own memory to avoid unpredictable performance arising from garbage collection. Scaling: ArangoDB provides scaling through clustering. Reliability: ArangoDB provides datacenter-to-datacenter replication.
Liebeskind–Srogl coupling Generation 2 Liebeskind–Srogl_coupling > Mechanism > Generation 2 The mechanism for the second generation is shown below. The mechanism does not follow a traditional oxidative addition-transmetelation-reductive elimination pathway like the first generation. In parallel to studies of Cu(I)-dioxygen reactions, a higher oxidation state, Cu-templated coupling is proposed. Coordination of copper(I) to the thioester undergoes oxidation by air to give a copper (II/III) intermediate. Metal templating by Cu(II/III) acts as a Lewis acid to both activate the thiol ester and deliver R2 (from either boron directly or via an intermediate Cu-R2 species), which produces the ketone and a Cu-thiolate. A second equivalent of boronic acid is needed to break the copper sulfur bond and liberate copper back into the catalytic cycle.
Phospholipase C Biological function Phospholipase_C > Biological function DAG is the substrate for the synthesis of phosphatidic acid, a regulatory molecule. IP3 is the rate-limiting substrate for the synthesis of inositol polyphosphates, which stimulate multiple protein kinases, transcription, and mRNA processing. Regulation of PLC activity is thus vital to the coordination and regulation of other enzymes of pathways that are central to the control of cellular physiology.
History of chemistry Ramsay's discovery of the noble gases History_of_chemistry > 19th century > Late 19th century > Ramsay's discovery of the noble gases The following year, Ramsay liberated another inert gas from a mineral called cleveite; this proved to be helium, previously known only in the solar spectrum. In his book The Gases of the Atmosphere (1896), Ramsay showed that the positions of helium and argon in the periodic table of elements indicated that at least three more noble gases might exist. In 1898 Ramsay and the British chemist Morris W. Travers isolated these elements—called neon, krypton, and xenon—from air and brought them to a liquid state at low temperature and high pressure.
Backpressure Routing Choosing the optimal commodity Backpressure_Routing > How it works > The backpressure control decisions > Choosing the optimal commodity The example suggests a symmetric relationship between neighbors (so that if 5 is a neighbor of 4, then 4 is a neighbor of 5), but this need not be the case in general. The set of neighbors of a given node determines the set of outgoing links it can use for transmission on the current slot. For each outgoing link (a,b), the optimal commodity c a b o p t ( t ) {\displaystyle c_{ab}^{opt}(t)} is defined as the commodity c ∈ { 1 , … , N } {\displaystyle c\in \{1,\ldots ,N\}} that maximizes the following differential backlog quantity: Q a ( c ) ( t ) − Q b ( c ) ( t ) {\displaystyle Q_{a}^{(c)}(t)-Q_{b}^{(c)}(t)} Any ties in choosing the optimal commodity are broken arbitrarily.
SDR SDRAM Virtual channel memory (VCM) SDRAM Prefetch_buffer > Failed successors > Virtual channel memory (VCM) SDRAM Once this is performed, the DRAM array may be precharged while read commands to the channel buffer continue. To write, first the data is written to a channel buffer (typically previous initialized using a Prefetch command), then a restore command, with the same parameters as the prefetch command, copies a segment of data from the channel to the sense amplifier array. Unlike a normal SDRAM write, which must be performed to an active (open) row, the VCSDRAM bank must be precharged (closed) when the restore command is issued.
Recessive inheritance Dominant-negative mutations Dominant_negative > Molecular mechanisms > Dominant-negative mutations A dominant-negative mutation may arise in a human somatic cell and provide a proliferative advantage to the mutant cell, leading to its clonal expansion. For instance, a dominant-negative mutation in a gene necessary for the normal process of programmed cell death (Apoptosis) in response to DNA damage can make the cell resistant to apoptosis.
Environmental and Resource Economics Related links Environmental_and_Resource_Economics > Related links European Association of Environmental and Resource Economists (EAERE)
Shock (circulatory) Distributive Shock_(circulatory) > Signs and symptoms > Distributive Patients who are receiving inotropic or vasopressor agents may have a normalized blood pressure at the time that perfusion abnormalities are identified. The pathophysiology behind septic shock is as follows: 1) Systemic leukocyte adhesion to endothelial cells 2) Reduced contractility of the heart 3) Activation of the coagulation pathways, resulting in disseminated intravascular coagulation 4). Increased levels of neutrophilsThe main manifestations of septic shock are due to the massive release of histamine which causes intense dilation of the blood vessels.
Theory of solar cells Photogeneration of charge carriers Theory_of_solar_cell > Photogeneration of charge carriers When a photon hits a piece of semiconductor, one of three things can happen: The photon can pass straight through the semiconductor — this (generally) happens for lower energy photons. The photon can reflect off the surface. The photon can be absorbed by the semiconductor if the photon energy is higher than the band gap value. This generates an electron-hole pair and sometimes heat depending on the band structure.When a photon is absorbed, its energy is given to an electron in the crystal lattice.
Dysprosium(III) fluoride Summary DyF3 Dysprosium(III) fluoride is an inorganic compound of dysprosium with a chemical formula DyF3.
Organizational analysis Control systems in the workplace Organizational_analysis > Performance management > Control systems in the workplace Companies encourage independence and innovation among employees in order to remain competitive, but in an effort to avoid unnecessary risk and control failures, companies must also put in place mechanisms to monitor employee progress. Included here are four major types of control levers or systems that enable managers to reconcile employee autonomy with effective control. Diagnostic Control Systems- Building and supporting clear targets Belief Systems- Communicating company core values and mission Boundary Systems- Specify and enforce rules of the game Interactive Control Systems- Open organizational dialogue to encourage learning
Atomic Physics Isolated atoms Atomic_Physics > Isolated atoms While modelling atoms in isolation may not seem realistic, if one considers atoms in a gas or plasma then the time-scales for atom-atom interactions are huge in comparison to the atomic processes that are generally considered. This means that the individual atoms can be treated as if each were in isolation, as the vast majority of the time they are. By this consideration, atomic physics provides the underlying theory in plasma physics and atmospheric physics, even though both deal with very large numbers of atoms.
Tetrakis(3,5-bis(trifluoromethyl)phenyl)borate Properties Tetrakis(3,5-bis(trifluoromethyl)phenyl)borate > Properties Non-coordinating anions are anions that interact only weakly with cations, a useful property when studying highly electrophilic cations. In coordination chemistry, the term can also be used to refer to anions which are unlikely to bind directly to the metal centre of a complex. Hexafluorophosphate is a non-coordinating anion in both senses of the term. Three widely used non-coordinating anions are hexafluorophosphate, tetrafluoroborate BF−4, and perchlorate ClO−4; of these, the hexafluorophosphate ion has the least coordinating ability and it is deliberately used for this property.
Flashsort Performance Flashsort > Performance Note that these measurements were taken in the late 1990s, when memory hierarchies were much less dependent on cacheing. Due to the in situ permutation that flashsort performs in its classification process, flashsort is not stable. If stability is required, it is possible to use a second array so elements can be classified sequentially. However, in this case, the algorithm will require O(n) additional memory.
Ehrenfest equations Limitations Ehrenfest_equations > Limitations Derivatives of Gibbs free energy are not always finite. Transitions between different magnetic states of metals can't be described by Ehrenfest equations.
Renin stability regulatory element (REN-SRE) Summary Renin_stability_regulatory_element_(REN-SRE) The Renin stability regulatory element (REN-SRE) is a cis-acting element identified in the 3'untranslated region (3'UTR) of the renin (REN) gene. It acts to regulate the levels of renin protein produced in the cell. Renin is secreted by renal juxtaglomerular cells and catalyses the conversion of angiotensinogen into angiotensin I which is the rate-limiting step in the production of angiotensin II.
Newtonian theory Work and energy Classical_billiard_balls > Description of the theory > Work and energy {\displaystyle \mathbf {F} =-\mathbf {\nabla } E_{\mathrm {p} }\,.} If all the forces acting on a particle are conservative, and Ep is the total potential energy (which is defined as a work of involved forces to rearrange mutual positions of bodies), obtained by summing the potential energies corresponding to each force F ⋅ Δ r = − ∇ E p ⋅ Δ r = − Δ E p . {\displaystyle \mathbf {F} \cdot \Delta \mathbf {r} =-\mathbf {\nabla } E_{\mathrm {p} }\cdot \Delta \mathbf {r} =-\Delta E_{\mathrm {p} }\,.}
Mental confusion Summary Mental_confusion In medicine, confusion is the quality or state of being bewildered or unclear. The term "acute mental confusion" is often used interchangeably with delirium in the International Statistical Classification of Diseases and Related Health Problems and the Medical Subject Headings publications to describe the pathology. These refer to the loss of orientation, or the ability to place oneself correctly in the world by time, location and personal identity. Mental confusion is sometimes accompanied by disordered consciousness (the loss of linear thinking) and memory loss (the inability to correctly recall previous events or learn new material).
Criticism of Twitter Trending topics Twitter > Appearance and features > Curation > Trending topics A word, phrase, or topic that is mentioned at a greater rate than others is said to be a "trending topic". Trending topics become popular either through a concerted effort by users or because of an event that prompts people to talk about a specific topic. These topics help Twitter and their users to understand what is happening in the world and what people's opinions are about it. The Twitter web interface displays a list of trending topics on a sidebar on the home page, along with sponsored content.
8-Oxoguanine Cancer, aging, infertility 8-Oxoguanine > Cancer, aging, infertility This accumulation may then lead upon replication of DNA to mutations including some that contribute to carcinogenesis. 8-oxoguanine is usually formed by the interaction of reactive oxygen species (ROS) with the guanine base in DNA under conditions of oxidative stress; as noted in the article about them, such species may have a role in aging and male infertility, and 8-oxoguanine can be used to measure such stress. == References ==
Optical metric Geometric optics and the optical metric Optical_metric > Geometric optics and the optical metric Thus, the determinant condition is insufficient to provide any information. However, the classical adjugate of a matrix M {\displaystyle M} is related to its determinant by M . a d j ( M ) = det ( M ) I {\displaystyle M.\mathrm {adj} (M)=\det(M)I} .
Phobia Amygdala Phobia > Mechanism > Limbic system > Amygdala When the fear or aggression response is initiated, the amygdala releases hormones into the body to put the human body into an "alert" state, which prepares the individual to move, run, fight, etc. This defensive "alert" state and response are known as the fight-or-flight response.However, inside the brain, this stress response can be observed in the hypothalamic-pituitary-adrenal axis (HPA). This circuit incorporates the process of receiving stimuli, interpreting them, and releasing certain hormones into the bloodstream. The parvocellular neurosecretory neurons of the hypothalamus release corticotropin-releasing hormone (CRH), which is sent to the anterior pituitary.
Pattern-Oriented Software Architecture Summary Pattern-Oriented_Software_Architecture Pattern-Oriented Software Architecture is a series of software engineering books describing software design patterns.
Nonlinear regression Transformation Nonlinear_regression > Linearization > Transformation These may not be desired effects. On the other hand, depending on what the largest source of error is, a nonlinear transformation may distribute the errors in a Gaussian fashion, so the choice to perform a nonlinear transformation must be informed by modeling considerations. For Michaelis–Menten kinetics, the linear Lineweaver–Burk plot 1 v = 1 V max + K m V max {\displaystyle {\frac {1}{v}}={\frac {1}{V_{\max }}}+{\frac {K_{m}}{V_{\max }}}} of 1/v against 1/ has been much used. However, since it is very sensitive to data error and is strongly biased toward fitting the data in a particular range of the independent variable, , its use is strongly discouraged. For error distributions that belong to the exponential family, a link function may be used to transform the parameters under the Generalized linear model framework.
Hubble time Redshift velocity Hubble_length > Interpretation > Redshift velocity and recessional velocity > Redshift velocity The "redshift velocity" vrs is not so simply related to real velocity at larger velocities, however, and this terminology leads to confusion if interpreted as a real velocity. Next, the connection between redshift or redshift velocity and recessional velocity is discussed. This discussion is based on Sartori.
Derivative Total derivative, total differential and Jacobian matrix Ordinary_derivative > In higher dimensions > Total derivative, total differential and Jacobian matrix That is, if f is a real-valued function of a real variable, then the total derivative exists if and only if the usual derivative exists. The Jacobian matrix reduces to a 1×1 matrix whose only entry is the derivative f′(x). This 1×1 matrix satisfies the property that f(a + h) − (f(a) + f ′(a)h) is approximately zero, in other words that f ( a + h ) ≈ f ( a ) + f ′ ( a ) h .
Linear filter Impulse response and transfer function Linear_filter > Impulse response and transfer function A linear time-invariant (LTI) filter can be uniquely specified by its impulse response h, and the output of any filter is mathematically expressed as the convolution of the input with that impulse response. The frequency response, given by the filter's transfer function H ( ω ) {\displaystyle H(\omega )} , is an alternative characterization of the filter. Typical filter design goals are to realize a particular frequency response, that is, the magnitude of the transfer function \| H ( ω ) \| {\displaystyle \|H(\omega )\|} ; the importance of the phase of the transfer function varies according to the application, inasmuch as the shape of a waveform can be distorted to a greater or lesser extent in the process of achieving a desired (amplitude) response in the frequency domain. The frequency response may be tailored to, for instance, eliminate unwanted frequency components from an input signal, or to limit an amplifier to signals within a particular band of frequencies.
Replication crisis Requiring smaller p-values Replication_crisis > Remedies > Statistical reform > Requiring smaller p-values Many publications require a p-value of p < 0.05 to claim statistical significance. The paper "Redefine statistical significance", signed by a large number of scientists and mathematicians, proposes that in "fields where the threshold for defining statistical significance for new discoveries is p < 0.05, we propose a change to p < 0.005. This simple step would immediately improve the reproducibility of scientific research in many fields." Their rationale is that "a leading cause of non-reproducibility (is that the) statistical standards of evidence for claiming new discoveries in many fields of science are simply too low. Associating 'statistically significant' findings with p < 0.05 results in a high rate of false positives even in the absence of other experimental, procedural and reporting problems. "This call was subsequently criticised by another large group, who argued that "redefining" the threshold would not fix current problems, would lead to some new ones, and that in the end, all thresholds needed to be justified case-by-case instead of following general conventions.
Correlation (projective geometry) In two dimensions Correlation_(projective_geometry) > In two dimensions In the real projective plane, points and lines are dual to each other. As expressed by Coxeter, A correlation is a point-to-line and a line-to-point transformation that preserves the relation of incidence in accordance with the principle of duality. Thus it transforms ranges into pencils, pencils into ranges, quadrangles into quadrilaterals, and so on.Given a line m and P a point not on m, an elementary correlation is obtained as follows: for every Q on m form the line PQ. The inverse correlation starts with the pencil on P: for any line q in this pencil take the point m ∩ q. The composition of two correlations that share the same pencil is a perspectivity.
Cubic polynomial Summary Cubic_polynomial In mathematics, a cubic function is a function of the form f ( x ) = a x 3 + b x 2 + c x + d , {\displaystyle f(x)=ax^{3}+bx^{2}+cx+d,} that is, a polynomial function of degree three. In many texts, the coefficients a, b, c, and d are supposed to be real numbers, and the function is considered as a real function that maps real numbers to real numbers or as a complex function that maps complex numbers to complex numbers. In other cases, the coefficients may be complex numbers, and the function is a complex function that has the set of the complex numbers as its codomain, even when the domain is restricted to the real numbers. Setting f(x) = 0 produces a cubic equation of the form a x 3 + b x 2 + c x + d = 0 , {\displaystyle ax^{3}+bx^{2}+cx+d=0,} whose solutions are called roots of the function.
Systemic functional linguistics Summary Systemic_functional_linguistics Language is above all a system; SFL maps the choices available in any language variety using its representation tool of a "system network". Functional signifies the proposition that language evolved under pressure of the functions that the language system must serve. Functions are taken to have left their mark on the structure and organisation of language at all levels, which is achieved via metafunctions.
Smoothed finite element method List of S-FEM models Smoothed_finite_element_method > List of S-FEM models Node-based Smoothed FEM (NS-FEM) Edge-based Smoothed FEM (ES-FEM) Face-based Smoothed FEM (FS-FEM) Cell-based Smoothed FEM (CS-FEM) Node/Edge-based Smoothed FEM (NS/ES-FEM) Alpha FEM method (Alpha FEM) Beta FEM method (Beta FEM)
Biotic stress Inducible defense responses to insect herbivores Biotic_stress > Response to stress > Inducible defense responses to insect herbivores Once detected, a signal transduction network is activated. The presence of an elicitor causes an influx of Ca2+ ions to be released in to the cytosol.
Dongfeng missile Dongfeng 11 (CSS-7) Dongfeng_missile > Dongfeng missiles > Dongfeng 11 (CSS-7) The DF-11 (CSS-7, also M-11 for export), is a road-mobile SRBM designed by Wang Zhenhua at the Sanjiang Missile Corporation (also known as the 066 Base) in the late 1970s. Unlike previous Chinese ballistic missiles, the DF-11 use solid fuel, which greatly reduces launch preparation time to around 15–30 minutes, while liquid-fuelled missiles such as the DF-5 require up to 2 hours of pre-launch preparation. The DF-11 has a range of 300 km and an 800 kg payload.
Attentional bias Measurement paradigms Attentional_bias > Measurements > Measurement paradigms Two stimuli of difference valences are presented simultaneously for a fixed time. Then, a probe replaces one of the two stimuli, which the participants have to respond to – by classifying the probe or responding to the location.Posner paradigm The Posner paradigm or Posner cueing task is similar to the dot-probe paradigm. It is a sight test, which assesses the individual's ability to switch and focus on different stimuli presented.
Inclusive Design History Inclusive_Design > History Coleman also published the first reference to the term in 1994 with The Case for Inclusive Design, a presentation at the 12th Triennial Congress of the International Ergonomics Association. Much of this early work was inspired by an aging population and people living for longer times in older ages as voiced by scholars like Peter Laslett. Public focus on accessibility further increased with the passage of the passage of the Americans with Disabilities Act of 1990, which expanded the responsibility of accessible design to include both public and private entities.In the 1990s, the United States followed the United Kingdom in shifting focus from universal design to inclusive design.
Magnetism Magnetism, electricity, and special relativity Magnetic_properties > Magnetism, electricity, and special relativity As a consequence of Einstein's theory of special relativity, electricity and magnetism are fundamentally interlinked. Both magnetism lacking electricity, and electricity without magnetism, are inconsistent with special relativity, due to such effects as length contraction, time dilation, and the fact that the magnetic force is velocity-dependent. However, when both electricity and magnetism are taken into account, the resulting theory (electromagnetism) is fully consistent with special relativity.
Street style Description Street_style > Description Also, he mentioned that streets tell a great deal about fashion and people, if you listen. According to him the best fashion show is coming to life every day on the streets. Street style is a viral, instant, addictive facet of fashion that has changed many of the ways in which fashion is made and consumed. Its fast characteristic links it also to the term consumerism. Given how styles change over time, it also challenges the use of fast fashion in relation to the purchasing and wearing of clothing, as this conceals the complexities of practice.
J. Robert Oppenheimer Scientific work J._Robert_Oppenheimer > Early career > Scientific work Years later, it was realized that the Sun was largely composed of hydrogen and that his calculations were correct.Oppenheimer made important contributions to the theory of cosmic ray showers. He also worked on the problem of field electron emission. This work contributed to the development of the concept of quantum tunneling.
Port mapping Local port forwarding Port_mapping > Types > Local port forwarding Local port forwarding is the most common type of port forwarding. It is used to let a user connect from the local computer to another server, i.e. forward data securely from another client application running on the same computer as a Secure Shell (SSH) client. By using local port forwarding, firewalls that block certain web pages, can be bypassed.Connections from an SSH client are forwarded, via an SSH server, to the intended destination server. The SSH server is configured to redirect data from a specified port (which is local to the host that runs the SSH client) through a secure tunnel to some specified destination host and port.
Lumped system analysis Thermal systems Lumped-capacitance_model > Thermal systems This law simply states that the temperature of a hot (or cold) object progresses toward the temperature of its environment in a simple exponential fashion. Objects follow this law strictly only if the rate of heat conduction within them is much larger than the heat flow into or out of them. In such cases it makes sense to talk of a single "object temperature" at any given time (since there is no spatial temperature variation within the object) and also the uniform temperatures within the object allow its total thermal energy excess or deficit to vary proportionally to its surface temperature, thus setting up the Newton's law of cooling requirement that the rate of temperature decrease is proportional to difference between the object and the environment. This in turn leads to simple exponential heating or cooling behavior (details below).
Endothelial lipase Vascular Biology Endothelial_lipase > Biological Function > Vascular Biology Data suggests that endothelial lipase inhibition should increase the plasma HDL, primarily in patients with low HDL-C levels. An increased risk of atherosclerosis is associated with low levels of HDL. Although a functional correlation can be drawn, there is little clinical evidence to provide support to the suggested potential benefits in vascular pathophysiology.
Vigesimal Europe Vigesimal > Use > Europe Twenty (ugain) is used as a base number in Welsh from numbers up to 50 (deg a deugain) and from 60 to 100 (cant), although since the 1940s a decimal counting system has come to be preferred. However, the vigesimal system exclusively is used for ordinal numbers and is still required in telling the time, money, and with weights and measures. Deugain means 'two twenties' i.e. 40, trigain means 'three twenties' i.e. 60, etc. dau ar bymtheg a deugain means 57 (two on fifteen and twenty).

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