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Mechanical equivalent of heat: Priority History and priority dispute Mechanical_equivalence_of_heat > History and priority dispute Thomson collaborated with Joule, mainly by correspondence, Joule conducting experiments, Thomson analysing the results and suggesting further experiments. The collaboration lasted from 1852 to 1856. Its published results did much to bring about general acceptance of Joule's work and the kinetic theory.
Postselection Summary Postselection Using postselection it seems quantum Turing machines are much more powerful: Scott Aaronson proved PostBQP is equal to PP. Some quantum experiments use post-selection after the experiment as a replacement for communication during the experiment, by post-selecting the communicated value into a constant. == References ==
Radiation belt Summary Radiation_belts The belts trap energetic electrons and protons. Other nuclei, such as alpha particles, are less prevalent.
Strength reduction Code analysis Strength_reduction > Code analysis Most of a program's execution time is typically spent in a small section of code (called a hot spot), and that code is often inside a loop that is executed over and over. A compiler uses methods to identify loops and recognize the characteristics of register values within those loops. For strength reduction, the compiler is interested in: Loop invariants: the values which do not change within the body of a loop. Induction variables: the values which are being iterated each time through the loop.Loop invariants are essentially constants within a loop, but their value may change outside of the loop.
Euler Gamma Function Relation to other functions Euler_Gamma_Function > Properties > Relation to other functions The reciprocal gamma function is an entire function and has been studied as a specific topic. The gamma function also shows up in an important relation with the Riemann zeta function, ζ ( z ) {\displaystyle \zeta (z)} . It also appears in the following formula: which is valid only for ℜ ( z ) > 1 {\displaystyle \Re (z)>1} .
Feature scaling Standardization (Z-score Normalization) Feature_scaling > Methods > Standardization (Z-score Normalization) Next we subtract the mean from each feature. Then we divide the values (mean is already subtracted) of each feature by its standard deviation. x ′ = x − x ¯ σ {\displaystyle x'={\frac {x-{\bar {x}}}{\sigma }}} Where x {\displaystyle x} is the original feature vector, x ¯ = average ( x ) {\displaystyle {\bar {x}}={\text{average}}(x)} is the mean of that feature vector, and σ {\displaystyle \sigma } is its standard deviation.
Diffraction topography Literature Diffraction_topography > Literature doi:10.1016/0001-6160(57)90002-0. ISSN 0001-6160. Lang, A. R.
Wind wave Breaking Wave_spectrum > Breaking They are often found where there is a sudden rise in the seafloor, such as a reef or sandbar. Deceleration of the wave base is sufficient to cause upward acceleration and a significant forward velocity excess of the upper part of the crest. The peak rises and overtakes the forward face, forming a "barrel" or "tube" as it collapses.
Pharmacology Drug discovery Therapeutic_drugs > Divisions > Clinical practice and drug discovery > Drug discovery Many methods have been proposed for quantitative predictions in drug metabolism; one example of a recent computational method is SPORCalc. A slight alteration to the chemical structure of a medicinal compound could alter its medicinal properties, depending on how the alteration relates to the structure of the substrate or receptor site on which it acts: this is called the structural activity relationship (SAR). When a useful activity has been identified, chemists will make many similar compounds called analogues, to try to maximize the desired medicinal effect(s).
Gitelman syndrome Cause Gitelman_syndrome > Cause This is another mechanism that might be responsible for decreased magnesium reabsorption.Another effect of the inactivated sodium-chloride cotransporter is the subsequent activation of the renin-angiotensin aldosterone system (RAAS). RAAS activation is a byproduct of the failure of the distal convoluted tubule in reabsorbing electrolytes, specifically sodium and chloride leading to cellular dehydration. RAAS attempts to compensate for this dehydration resulting in low serum blood potassium.Some patients have symptoms that fit with a diagnosis of Gitelman syndrome, while a genetic defect in the SLC12A3 gene cannot be found. In these cases, a different genetic defect can sometimes be identified, although some cases remain idiopathic.
Generational garbage collection Stop-the-world vs. incremental vs. concurrent Tracing_garbage_collection > Implementation strategies > Stop-the-world vs. incremental vs. concurrent Simple stop-the-world garbage collectors completely halt execution of the program to run a collection cycle, thus guaranteeing that new objects are not allocated and objects do not suddenly become unreachable while the collector is running. This has the disadvantage that the program can perform no useful work while a collection cycle is running (sometimes called the "embarrassing pause"). Stop-the-world garbage collection is therefore mainly suitable for non-interactive programs. Its advantage is that it is both simpler to implement and faster than incremental garbage collection.
Object-based attention Cues and attentional focus Object-based_attention > Factors that influence object-based attention > Cues and attentional focus The kind of cues—exogenous (peripheral) or endogenous (central)—have been found to differentially affect the role of object-based attention in visual searches. Chen reported that object-based effects were found with exogenous but not with endogenous cues. : 1 However, further research into this finding suggests that it is rather the extent of attentional focus that a cue evokes that influences the functioning of an object-based effect, than the kind of cue used. Object effects are less elusive when the peripheral nature of exogenous cues is responsible for stimulating the use of a broad focus of attention vis-à-vis the narrow attentional focus generally induced by central-type cues. Confirmatory findings in the ‘extent of attentional focus’ versus ‘type of cue’ debate by Chen & Cave, and others, have shown that object-based effects are also evident in the case of endogenous cues when research-participants adopt a broad attentional focus while attending to the cues.
Action semantics Yielder entities Action_semantics > Yielder entities Yielder entities consist of unevaluated quantities of data. The values of these quantities are contingent on the current information and state of computation. Yielders draw on transient data, bindings, and storage to select the information to be processed by actions.
Strong consistency Summary Strong_consistency Strong consistency is one of the consistency models used in the domain of concurrent programming (e.g., in distributed shared memory, distributed transactions).The protocol is said to support strong consistency if: All accesses are seen by all parallel processes (or nodes, processors, etc.) in the same order (sequentially)Therefore, only one consistent state can be observed, as opposed to weak consistency, where different parallel processes (or nodes, etc.) can perceive variables in different states.
Tunnel magnetoresistance History Magnetic_tunnel_junctions > History The effect was originally discovered in 1975 by Michel Jullière (University of Rennes, France) in Fe/Ge-O/Co-junctions at 4.2 K. The relative change of resistance was around 14%, and did not attract much attention. In 1991 Terunobu Miyazaki (Tohoku University, Japan) found a change of 2.7% at room temperature. Later, in 1994, Miyazaki found 18% in junctions of iron separated by an amorphous aluminum oxide insulator and Jagadeesh Moodera found 11.8% in junctions with electrodes of CoFe and Co. The highest effects observed at this time with aluminum oxide insulators was around 70% at room temperature.
Classical XY model Two dimensions XY_model > Rigorous results > Two dimensions The two-dimensional XY model with nearest-neighbor interactions is an example of a two-dimensional system with continuous symmetry that does not have long-range order as required by the Mermin–Wagner theorem. Likewise, there is not a conventional phase transition present that would be associated with symmetry breaking. However, as will be discussed later, the system does show signs of a transition from a disordered high-temperature state to a quasi-ordered state below some critical temperature, called the Kosterlitz-Thouless transition. In the case of a discrete lattice of spins, the two-dimensional XY model can be evaluated using the transfer matrix approach, reducing the model to an eigenvalue problem and utilizing the largest eigenvalue from the transfer matrix.
Timed automaton Summary Timed_automaton Further, clocks can be reset. Timed automata are a sub-class of a type hybrid automata. Timed automata can be used to model and analyse the timing behavior of computer systems, e.g., real-time systems or networks.
Plant lifecycle management Physical model Plant_lifecycle_management > Parts of the model > Physical model Physical parts of a plant are usually represented by 3D CAD models. The CAD system used would typically focus on top-down, routing, and DMU and would differ on many point from the systems used in the mechanical industry, or for Architectural engineering. Sometimes the CAD system would be supplemented by software to generate 3D views or walk-through features.
Servoamplifier Function Servo_drive > Function It then alters the voltage, frequency or pulse width to the motor so as to correct for any deviation from the commanded status.In a properly configured control system, the servo motor rotates at a velocity that very closely approximates the velocity signal being received by the servo drive from the control system. Several parameters, such as stiffness (also known as proportional gain), damping (also known as derivative gain), and feedback gain, can be adjusted to achieve this desired performance. The process of adjusting these parameters is called performance tuning. Although many servo motors require a drive specific to that particular motor brand or model, many drives are now available that are compatible with a wide variety of motors..
Resonance energy Comparison with molecular orbital (MO) theory Resonance_energy > Quantum mechanical description in valence bond (VB) theory > Comparison with molecular orbital (MO) theory They lead to the models of contributing structures for an electron-withdrawing group and electron-releasing group on benzene. The utility of MO theory is that a quantitative indication of the charge from the π system on an atom can be obtained from the squares of the weighting coefficient ci on atom Ci. Charge qi ≈ c2i.
Pillow plate heat exchanger Pillow plate banks (heat exchangers) Pillow-plate_heat_exchanger > Application > Pillow plate banks (heat exchangers) Pillow plate banks are typically used in applications involving liquid-liquid, gas-liquid, high viscosity or dirty media, low pressure loss requirements, condensation (e.g. top condensers), falling film evaporation (e.g. paper & pulp industry), reboilers, water chilling, drying of solids, flake ice generation (food industry) and more. They are also commonly used as immersion chillers (e.g. in electroplating), where the banks are immersed directly into the tank. Banks can be constructed to allow the individual plates to be separated from the stack, allowing easy cleaning or maintenance.
Ternary search tree Tries Ternary_search_tree > Comparison to other data structures > Tries While being slower than other prefix trees, ternary search trees can be better suited for larger data sets due to their space-efficiency.
Mechanical design Modern tools Mechanical_design > Modern tools In addition, CAE analysis programs can model complicated physical phenomena which cannot be solved by hand, such as viscoelasticity, complex contact between mating parts, or non-Newtonian flows. As mechanical engineering begins to merge with other disciplines, as seen in mechatronics, multidisciplinary design optimization (MDO) is being used with other CAE programs to automate and improve the iterative design process. MDO tools wrap around existing CAE processes, allowing product evaluation to continue even after the analyst goes home for the day. They also use sophisticated optimization algorithms to more intelligently explore possible designs, often finding better, innovative solutions to difficult multidisciplinary design problems.
Main diagonal Antidiagonal Main_diagonal > Antidiagonal The antidiagonal (sometimes counter diagonal, secondary diagonal, trailing diagonal, minor diagonal, off diagonal, or bad diagonal) of an order N {\displaystyle N} square matrix B {\displaystyle B} is the collection of entries b i , j {\displaystyle b_{i,j}} such that i + j = N + 1 {\displaystyle i+j=N+1} for all 1 ≤ i , j ≤ N {\displaystyle 1\leq i,j\leq N} . That is, it runs from the top right corner to the bottom left corner. {\displaystyle {\begin{bmatrix}0&0&\color {red}{1}\\0&\color {red}{1}&0\\\color {red}{1}&0&0\end{bmatrix}}}
Ultra-Low Fouling Making ultra-low fouling surfaces Ultra-Low_Fouling > Making ultra-low fouling surfaces High surface energies cause adsorption because a contaminated surface will have a smaller difference between the surface and bulk coordination numbers. This drives the surface to reach a lower, more favored, energy state. A low energy surface would then be desired to prevent adsorption. It would be convenient if the desired surface was already low energy, but in many cases-such as metals-this is not the case.
3 Science 3 > Science Humans perceive the universe to have three spatial dimensions, but some theories, such as string theory, suggest there are more. Three is the number of elementary fermion generations according to the Standard Model of particle physics. The triangle, a polygon with three edges and three vertices, is the most stable physical shape.
Bilge Bilge water Bilge_water > Bilge water The word is sometimes also used to describe the water that collects in this area. Water that does not drain off the side of the deck or through a hole in the hull, typically via a scupper, drains down into the ship into the bilge. This water may be from rough seas, rain, leaks in the hull or stuffing box, or other interior spillage. The collected water must be pumped out to prevent the bilge from becoming too full and threatening to sink the ship.
Visual cues Use in technology for the visually impaired Sensory_cue > Haptic cues > Haptic cues in research > Use in technology for the visually impaired Haptic cues are used frequently to allow those who have impaired vision to have access to a greater wealth of information. Braille is a tactile written language which is read via touch, brushing the fingers over the raised patterns. Braille technology is the attempt to extend Braille to digital media and developing new tools to aid in the reading of web pages and other electronic devices often involves a combination of haptic and auditory cues.A major issue that different technologies in this area attempt to overcome is sensory overload. The amount of information that can be quickly related via touch is less than that of vision and is limited by current technology. As a result, multi-modal approaches, converting the visual information into both haptic and auditory outputs, often have the best results. For example, an electronic pen can be drawn across a tablet mapped to the screen and produce different vibrations and sounds depending on what is at that location.
Diffraction topography Literature Diffraction_topography > Literature "The use of synchrotron edge topography to study polytype nearest neighbour relationships in SiC" (PDF). Radiation Physics and Chemistry. Elsevier BV.
Infections associated with diseases Summary Infections_associated_with_diseases When using this method, absolute statements regarding causation are not always possible. Higher amounts of distinctive pathogenic nucleic acid sequences should be in those exhibiting disease, compared to controls. In addition, the DNA load should become lower with the resolution of the disease.
Random sample consensus Overview Random_sample_consensus > Overview The RANSAC algorithm is a learning technique to estimate parameters of a model by random sampling of observed data. Given a dataset whose data elements contain both inliers and outliers, RANSAC uses the voting scheme to find the optimal fitting result. Data elements in the dataset are used to vote for one or multiple models. The implementation of this voting scheme is based on two assumptions: that the noisy features will not vote consistently for any single model (few outliers) and there are enough features to agree on a good model (few missing data).
Henry Louis Le Chatelier Early life Henry_Louis_Le_Chatelier > Early life His mother raised the children by regimen, described by Henry Louis: "I was accustomed to a very strict discipline: it was necessary to wake up on time, to prepare for your duties and lessons, to eat everything on your plate, etc. All my life I maintained respect for order and law. Order is one of the most perfect forms of civilization. "As a child, Le Chatelier attended the Collège Rollin in Paris.
Patient participation Limitations and criticism Patient_participation > In health technology assessment > Limitations and criticism There are many ways that public participation in HTA, including patients, can be implemented. In fact, an entire "typology of issues" has been developed by Gauvin et al., in which each type is "related to the most appropriate public involvement methods".
Aerobic decomposition Rate of decomposition Bacterial_decay > Rate of decomposition Substances like sugars and amino acids decompose readily and are considered labile. Cellulose and hemicellulose, which are broken down more slowly, are "moderately labile". Compounds which are more resistant to decay, like lignin or cutin, are considered recalcitrant.
Online machine learning Implementations Online_machine_learning > Implementations Vowpal Wabbit: Open-source fast out-of-core online learning system which is notable for supporting a number of machine learning reductions, importance weighting and a selection of different loss functions and optimisation algorithms. It uses the hashing trick for bounding the size of the set of features independent of the amount of training data. scikit-learn: Provides out-of-core implementations of algorithms for Classification: Perceptron, SGD classifier, Naive bayes classifier.
Superlens Perfect lenses Hyperlens > Development and construction > Perfect lenses When the world is observed through conventional lenses, the sharpness of the image is determined by and limited to the wavelength of light. Around the year 2000, a slab of negative index metamaterial was theorized to create a lens with capabilities beyond conventional (positive index) lenses. Pendry proposed that a thin slab of negative refractive metamaterial might overcome known problems with common lenses to achieve a "perfect" lens that would focus the entire spectrum, both the propagating as well as the evanescent spectra.A slab of silver was proposed as the metamaterial. More specifically, such silver thin film can be regarded as a metasurface.
Wood industry Importance in limiting climate change Wood_industry > Economy > Importance in limiting climate change Regarding the problem of climate change, it is known that burning forests increase CO2 in the atmosphere, while intact virgin forest or plantations act as sinks for CO2, for these reasons wood economy fights greenhouse effect. The amount of CO2 absorbed depends on the type of trees, lands and the climate of the place where trees naturally grow or are planted. Moreover, by night plants do not photosynthesize, and produce CO2, eliminated the successive day. Paradoxically in summer oxygen created by photosynthesis in forests near to cities and urban parks, interacts with urban air pollution (from cars, etc.) and is transformed by solar beams in ozone (molecule of three oxygen atoms), that while in high atmosphere constitutes a filter against ultraviolet beams, in the low atmosphere is a pollutant, able to provoke respiratory disturbances.In a low-carbon economy, forestry operations will be focused on low-impact practices and regrowth.
Deviance (sociology) Control theory Deviance_(sociology) > Theories of deviance > Symbolic interaction > Control theory Without this "control", deviant behavior would happen more often. This leads to conformity and groups. People will conform to a group when they believe they have more to gain from conformity than by deviance.
Sedimentary depositional environment Types of depositional environments Depositional_environment > Types of depositional environments Creates beaches, spits, and sandbars with the common sediments of gravel and sand. Lake – Large body of relatively still waterMarine Shallow water marine environment – processes due to waves and tidal currents, creates shelves and slopes, lagoons. Common sediments are carbonates (in tropical climates) or sand, silt, and clay (elsewhere) Upper shoreface – Portion of the seafloor that is shallow enough to be agitated by everyday wave action Lower shoreface – Part of the seafloor undisturbed by waves Deep water marine environment – Flat area on the deep ocean floor (abyssal plains) caused by ocean currents.
Impact of the COVID-19 pandemic on healthcare workers Centers for Disease Control and Prevention Impact_of_the_COVID-19_pandemic_on_healthcare_workers > Recommendations > Centers for Disease Control and Prevention The Centers for Disease Control and Prevention has issued guidance on preventing transmission and reducing job stress in response to the COVID-19 pandemic for healthcare workers:
Double-layer capacitor Literature Electric_double-layer_capacitor > Literature pp. 329–375. doi:10.1201/9781420055405-c8.
Vortex lattice method Historical background Vortex_lattice_method > Historical background Although the computations needed can be carried out by hand, the VLM benefited from the advent of computers for the large amounts of computations that are required. Instead of only one horseshoe vortex per wing, as in the Lifting-line theory, the VLM utilizes a lattice of horseshoe vortices, as described by Falkner in his first paper on this subject in 1943. The number of vortices used vary with the required pressure distribution resolution, and with required accuracy in the computed aerodynamic coefficients. A typical number of vortices would be around 100 for an entire aircraft wing; an Aeronautical Research Council report by Falkner published in 1949 mentions the use of an "84-vortex lattice before the standardisation of the 126-lattice" (p. 4).The method is comprehensibly described in all major aerodynamic textbooks, such as Katz & Plotkin, Anderson, Bertin & Smith Houghton & Carpenter or Drela,
Ascoli's theorem Necessity Ascoli's_theorem > Necessity Whereas most formulations of the Arzelà–Ascoli theorem assert sufficient conditions for a family of functions to be (relatively) compact in some topology, these conditions are typically also necessary. For instance, if a set F is compact in C(X), the Banach space of real-valued continuous functions on a compact Hausdorff space with respect to its uniform norm, then it is bounded in the uniform norm on C(X) and in particular is pointwise bounded. Let N(ε, U) be the set of all functions in F whose oscillation over an open subset U ⊂ X is less than ε: N ( ε , U ) = { f ∣ osc U ⁡ f < ε } . {\displaystyle N(\varepsilon ,U)=\{f\mid \operatorname {osc} _{U}f<\varepsilon \}.} For a fixed x∈X and ε, the sets N(ε, U) form an open covering of F as U varies over all open neighborhoods of x. Choosing a finite subcover then gives equicontinuity.
Direct Current Various definitions DC_voltage > Various definitions The term DC is used to refer to power systems that use only one electrical polarity of voltage or current, and to refer to the constant, zero-frequency, or slowly varying local mean value of a voltage or current. For example, the voltage across a DC voltage source is constant as is the current through a direct current source. The DC solution of an electric circuit is the solution where all voltages and currents are constant. It can be shown that any stationary voltage or current waveform can be decomposed into a sum of a DC component and a zero-mean time-varying component; the DC component is defined to be the expected value, or the average value of the voltage or current over all time.
Crevice corrosion Stress corrosion cracking Crevice_corrosion > Stress corrosion cracking A common form of crevice failure occurs due to stress corrosion cracking, where a crack or cracks develop from the base of the crevice where the stress concentration is greatest. This was the root cause of the fall of the Silver Bridge over the Ohio River, in 1967 in West Virginia, where a single critical crack only about 3 mm long suddenly grew and fractured a tie bar joint. The rest of the bridge fell in less than a minute. The disaster was caused by one single point of failure (SPOF).
X-ray photoelectron spectroscopy Vibrational effects X-ray_photoelectron_spectroscopy > Theoretical aspects > Theory of core level photoemission of electrons > Vibrational effects Temperature-dependent atomic lattice vibrations, or phonons, can broaden the core level components and attenuate the interference patterns in an X-ray photoelectron diffraction (XPD) experiment. The simplest way to account for vibrational effects is by multiplying the scattered single-photoelectron wave function ϕ j {\displaystyle \phi _{j}} by the Debye–Waller factor: W j = exp ⁡ ( − Δ k j 2 U j 2 ¯ ) {\displaystyle W_{j}=\exp {(-\Delta k_{j}^{2}{\bar {U_{j}^{2}}})}} ,where Δ k j 2 {\displaystyle \Delta k_{j}^{2}} is the squared magnitude of the wave vector variation caused by scattering, and U j 2 ¯ {\displaystyle {\bar {U_{j}^{2}}}} is the temperature-dependent one-dimensional vibrational mean squared displacement of the j t h {\displaystyle j^{th}} emitter. In the Debye model, the mean squared displacement is calculated in terms of the Debye temperature, Θ D {\displaystyle \Theta _{D}} , as: U j 2 ¯ ( T ) = 9 ℏ 2 T 2 / m k B Θ D {\displaystyle {\bar {U_{j}^{2}}}(T)=9\hbar ^{2}T^{2}/mk_{B}\Theta _{D}}
Culture and sensitivity Reporting Culture_and_sensitivity > Reporting The results of the testing are reported as a table, sometimes called an antibiogram. Bacteria are marked as sensitive, resistant, or having intermediate resistance to an antibiotic based on the minimum inhibitory concentration (MIC), which is the lowest concentration of the antibiotic that stops the growth of bacteria. The MIC is compared to standard threshold values (called "breakpoints") for a given bacterium and antibiotic. Breakpoints for the same organism and antibiotic may differ based on the site of infection: for example, the CLSI generally defines Streptococcus pneumoniae as sensitive to intravenous penicillin if MICs are ≤0.06 μg/ml, intermediate if MICs are 0.12 to 1 μg/ml, and resistant if MICs are ≥2 μg/ml, but for cases of meningitis, the breakpoints are considerably lower.
Kidney tumour Malignant (cancerous) Renal_tumor > Diagnosis > Classification > Malignant (cancerous) This stage accounts for 17% of kidney cancers and 69% of people are expected to live 5 years with this progression of kidney cancer. •Stage 4, the kidney tumour has spread to a distant organ or lymph node. 16% of kidney cancers are progressed to this stage and of those people, 12% of them are expected to live 5 years.
Vitamin B12 deficiency Impaired absorption Vitamin_B12_deficiency > Causes > Impaired absorption The diabetes medication metformin may interfere with B12 dietary absorption. A genetic disorder, transcobalamin II deficiency can be a cause.
Dimensional models of personality disorders Adapted categorical models Dimensional_models_of_personality_disorders > Model development > Adapted categorical models There are different ways to ‘dimensionalize’ personality disorders, these can be summarised into two categories. The first involves quantifying DSM-5 pathology. This can be done either based on the degree to which symptoms are present or on how close to a prototypic presentation a patient's presentation may be. The prototype approach includes features not present in the DSM. The second approach involves identification of DSM disorder traits by means of factor analysis to show underlying dimensions of the personality disorder criteria, this method may also include relevant psychopathology.
Fast-reverse epitaxial diode field-effect transistor More about terminals Field-effect_transistor > More about terminals All FETs have source, drain, and gate terminals that correspond roughly to the emitter, collector, and base of BJTs. Most FETs have a fourth terminal called the body, base, bulk, or substrate. This fourth terminal serves to bias the transistor into operation; it is rare to make non-trivial use of the body terminal in circuit designs, but its presence is important when setting up the physical layout of an integrated circuit. The size of the gate, length L in the diagram, is the distance between source and drain.
Kato technique Summary Kato_technique The Kato technique (also called the Kato–Katz technique) is a laboratory method for preparing human stool samples prior to searching for parasite eggs.
AIDS virus Replication and transcription HIV_virus > Virology > Replication cycle > Replication and transcription This means that those cells most likely to be targeted, entered and subsequently killed by HIV are those actively fighting infection. During viral replication, the integrated DNA provirus is transcribed into RNA. The full-length genomic RNAs (gRNA) can be packaged into new viral particles in a pseudodiploid form.
Distributed Hash Table Rendezvous hashing Distributed_Hash_Table > Structure > Keyspace partitioning > Rendezvous hashing In rendezvous hashing, also called highest random weight (HRW) hashing, all clients use the same hash function h ( ) {\displaystyle h()} (chosen ahead of time) to associate a key to one of the n available servers. Each client has the same list of identifiers {S1, S2, ..., Sn }, one for each server. Given some key k, a client computes n hash weights w1 = h(S1, k), w2 = h(S2, k), ..., wn = h(Sn, k). The client associates that key with the server corresponding to the highest hash weight for that key. A server with ID S x {\displaystyle S_{x}} owns all the keys k m {\displaystyle k_{m}} for which the hash weight h ( S x , k m ) {\displaystyle h(S_{x},k_{m})} is higher than the hash weight of any other node for that key.
Sugar battery Thermo Enzymes Sugar_battery > Improvements > Thermo Enzymes Thermoenzymes, enzymes with high thermostability, are used as the non-immobilized enzymes to ensure stability. In the sugar battery, the thermo enzymes are produced by Escherichia coli, a kind of bacterium. Then the enzymes are purified through heat precipitation method and put into use.
Supersymmetric theory of stochastic dynamics Classification of stochastic dynamics Supersymmetric_theory_of_stochastic_dynamics > Applications > Classification of stochastic dynamics In the deterministic limit, ordered phase is equivalent to deterministic chaotic dynamics with non-integrable flow. Ordered non-integrable phase can be called chaos or C-phase because ordinary deterministic chaos belongs to it. Ordered integrable phase can be called noise-induced chaos or N-phase because it disappears in the deterministic limit. TS is broken by the condensation of (anti-)instantons (see below). At stronger noises, the sharp N-C boundary must smear out into a crossover because (anti-)instantons lose their individuality and it is hard for an external observer to tell one tunneling process from another.
Model Predictive Control Nonlinear MPC Model_Predictive_Control > Nonlinear MPC NMPC algorithms typically exploit the fact that consecutive optimal control problems are similar to each other. This allows to initialize the Newton-type solution procedure efficiently by a suitably shifted guess from the previously computed optimal solution, saving considerable amounts of computation time. The similarity of subsequent problems is even further exploited by path following algorithms (or "real-time iterations") that never attempt to iterate any optimization problem to convergence, but instead only take a few iterations towards the solution of the most current NMPC problem, before proceeding to the next one, which is suitably initialized; see, e.g.,.. Another promising candidate for the nonlinear optimization problem is to use a randomized optimization method.
Viral myocarditis Summary Viral_myocarditis Myocarditis, also known as inflammatory cardiomyopathy, is an acquired cardiomyopathy due to inflammation of the heart muscle. Symptoms can include shortness of breath, chest pain, decreased ability to exercise, and an irregular heartbeat. The duration of problems can vary from hours to months. Complications may include heart failure due to dilated cardiomyopathy or cardiac arrest.Myocarditis is most often due to a viral infection.
Social discovery platform Developments Social_search_engine > Developments The new Tailored Trends feature, besides showing Twitter trends, will give a short description of each topic. Since trends tend to be abbreviations without context, a description will make it more clear what a trend is about. The new trends experience may also include how many Tweets have been sent and whether a topic is trending up or down.Google may be falling behind in terms of social search, but in reality they see the potential and importance of this technology with Web 3.0 and web semantics.
Quantum Machine Learning Quantum Convolution Neural Network Quantum_artificial_intelligence > Machine learning with quantum computers > Quantum Convolution Neural Network Despite the fact that the QCNN model does not include the corresponding quantum operation, the fundamental idea of the pooling layer is also offered to assure validity. In QCNN architecture, the pooling layer is typically placed between succeeding convolutional layers. Its function is to shrink the representation's spatial size while preserving crucial features, which allows it to reduce the number of parameters, streamline network computing, and manage over-fitting.
Handshake History Handshake > History For example, a depiction of two soldiers shaking hands can be found on part of a 5th-century BC funerary stele that is on display in Berlin’s Pergamon Museum (stele SK1708) and on other funerary steles, such as one from the 4th century BC that depicts Thraseas and his wife Euandria shaking hands. Depictions of handshakes also appear in Archaic Greek, Etruscan and Roman funerary and non-funerary art. Muslim scholars have written that the custom of handshaking was introduced to them by the people of Yemen.
Binding site Applications Binding_site > Applications Inhibition of this function represses neoplastic growth and improves severe psoriasis and adult rheumatoid arthritis.In cardiovascular illnesses, drugs such as beta blockers are used to treat patients with hypertension. Beta blockers (β-Blockers) are antihypertensive agents that block the binding of the hormones adrenaline and noradrenaline to β1 and β2 receptors in the heart and blood vessels. These receptors normally mediate the sympathetic "fight or flight" response, causing constriction of the blood vessels.Competitive inhibitors are also largely found commercially. Botulinum toxin, known commercially as Botox, is a neurotoxin that causes flaccid paralysis in the muscle due to binding to acetylcholine dependent nerves. This interaction inhibits muscle contractions, giving the appearance of smooth muscle.
Search coil magnetometer Applications Search_coil_magnetometer > Applications Eye tracker: a search coil is used to measure eye movement using coils that are embedded into a contact lens. Education Non-destructive testing Magnetotellurics Space research Natural electromagnetic waves observations on Earth.
Autonomous mobile robot Collision avoidance Automatic_guided_vehicle > Traffic control > Collision avoidance Forward sensing control uses collision avoidance sensors to avoid collisions with other AGV in the area. These sensors include: sonic, which work like radar; optical, which uses an infrared sensor; and bumper, physical contact sensor. Most AGV's are equipped with a bumper sensor of some sort as a fail-safe. Sonic sensors send a "chirp" or high frequency signal out and then wait for a reply from the outline of the reply the AGV can determine if an object is ahead of it and take the necessary actions to avoid collision.
Unrolled linked list Overview Unrolled_linked_list > Overview If the array is already full, we first insert a new node either preceding or following the current one and move half of the elements in the current node into it. To remove an element, we find the node it is in and delete it from the elements array, decrementing numElements. If this reduces the node to less than half-full, then we move elements from the next node to fill it back up above half. If this leaves the next node less than half full, then we move all its remaining elements into the current node, then bypass and delete it.
Nuclear power proposed as renewable energy Definitions of renewable energy Nuclear_power_proposed_as_renewable_energy > Definitions of renewable energy Renewable energy flows involve natural phenomena, which with the exception of tidal power, ultimately derive their energy from the sun (a natural fusion reactor) or from geothermal energy, which is heat derived in greatest part from that which is generated in the earth from the decay of radioactive isotopes, as the International Energy Agency explains: Renewable energy is derived from natural processes that are replenished constantly. In its various forms, it derives directly from the sun, or from heat generated deep within the earth. Included in the definition is electricity and heat generated from sunlight, wind, oceans, hydropower, biomass, geothermal resources, and biofuels and hydrogen derived from renewable resources. Renewable energy resources exist over wide geographical areas, in contrast to other energy sources, which are concentrated in a limited number of countries.In ISO 13602-1:2002, a renewable resource is defined as "a natural resource for which the ratio of the creation of the natural resource to the output of that resource from nature to the technosphere is equal to or greater than one".
Nonlinear resonance Description Nonlinear_resonance > Description This representation allows to reconstruct uniquely 3a) dynamical system describing time-dependent behavior of the cluster, and 3b) the set of its polynomial conservation laws; these are generalization of Manley–Rowe constants of motion for the simplest clusters (triads and quartets). Dynamical systems describing some types of the clusters can be solved analytically; these are the exactly solvable models. These theoretical results can be used directly for describing real-life physical phenomena (e.g. intraseasonal oscillations in the Earth's atmosphere) or various wave turbulent regimes in the theory of wave turbulence. Many more examples are provided in the article on resonant interactions.
Energy eigenstate Stationary state properties Energy_eigenvalues > Stationary state properties As shown above, a stationary state is not mathematically constant: However, all observable properties of the state are in fact constant in time. For example, if \| Ψ ( t ) ⟩ {\displaystyle \|\Psi (t)\rangle } represents a simple one-dimensional single-particle wavefunction Ψ ( x , t ) {\displaystyle \Psi (x,t)} , the probability that the particle is at location x is which is independent of the time t. The Heisenberg picture is an alternative mathematical formulation of quantum mechanics where stationary states are truly mathematically constant in time. As mentioned above, these equations assume that the Hamiltonian is time-independent. This means simply that stationary states are only stationary when the rest of the system is fixed and stationary as well. For example, a 1s electron in a hydrogen atom is in a stationary state, but if the hydrogen atom reacts with another atom, then the electron will of course be disturbed.
Examples of Markov chains A simple weather model Examples_of_Markov_chains > Discrete-time > A simple weather model The probabilities of weather conditions (modeled as either rainy or sunny), given the weather on the preceding day, can be represented by a transition matrix: P = {\displaystyle P={\begin{bmatrix}0.9&0.1\\0.5&0.5\end{bmatrix}}} The matrix P represents the weather model in which a sunny day is 90% likely to be followed by another sunny day, and a rainy day is 50% likely to be followed by another rainy day. The columns can be labelled "sunny" and "rainy", and the rows can be labelled in the same order. (P)i j is the probability that, if a given day is of type i, it will be followed by a day of type j. Notice that the rows of P sum to 1: this is because P is a stochastic matrix.
Inner moon Orbits Inner_moon > Orbits This is why photos of these satellites show them to be completely clean of pebbles, dust and rocks. The most extreme cases are Saturn's moon Pan, which orbits within the rings at only 70% of its fluid Roche limit, as well as Neptune's moon Naiad. Naiad's density is unknown, so its precise Roche limit is also unknown, but if its density were below 1100 kg/m3 it would lie at an even smaller fraction of its Roche limit than Pan.
Weyl calculus Theory in higher dimensions Oscillator_semigroup > Applications and generalizations > Theory in higher dimensions {\displaystyle {{\widehat {f}}(t)={1 \over (2\pi )^{n/2}}\int _{{\mathbf {R} }^{n}}f(x)e^{-ix\cdot t}\,dx.}} The Fourier inversion formula f ( x ) = 1 ( 2 π ) n / 2 ∫ R n f ^ ( t ) e i x ⋅ t d t {\displaystyle {f(x)={1 \over (2\pi )^{n/2}}\int _{{\mathbf {R} }^{n}}{\widehat {f}}(t)e^{ix\cdot t}\,dt}} shows that the Fourier transform is an isomorphism of S {\displaystyle {\mathcal {S}}} onto itself extending to a unitary mapping of L2(Rn) onto itself (Plancherel's theorem). The Stone–von Neumann theorem asserts that the Schrödinger representation is irreducible and is the unique irreducible representation of the commutation relations: any other representation is a direct sum of copies of this representation.
Inverse trigonometric function Principal values Arc_cosine > Basic concepts > Principal values Since none of the six trigonometric functions are one-to-one, they must be restricted in order to have inverse functions. Therefore, the result ranges of the inverse functions are proper (i.e. strict) subsets of the domains of the original functions. For example, using function in the sense of multivalued functions, just as the square root function y = x {\displaystyle y={\sqrt {x}}} could be defined from y 2 = x , {\displaystyle y^{2}=x,} the function y = arcsin ⁡ ( x ) {\displaystyle y=\arcsin(x)} is defined so that sin ⁡ ( y ) = x . {\displaystyle \sin(y)=x.}
Cross development Summary Cross_compiler Cross compilers are distinct from source-to-source compilers. A cross compiler is for cross-platform software generation of machine code, while a source-to-source compiler translates from one coding language to another in text code. Both are programming tools.
Synchronization complexity Interpretation Cyclomatic_complexity > Description > Interpretation In his presentation 'Software Quality Metrics to Identify Risk' for the Department of Homeland Security, Tom McCabe introduces the following categorisation to interpret cyclomatic complexity: 1 - 10 Simple procedure, little risk 11 - 20 More complex, moderate risk 21 - 50 Complex, high risk > 50 Untestable code, very high risk
Link-state protocol Optimizations to the algorithm Link-state_protocol > Optimizations to the algorithm The algorithm described above was made as simple as possible, to aid in ease of understanding. In practice, there are a number of optimizations which are used.
Private biometrics Background Private_biometrics > Background Biometric security strengthens user authentication but, until recently, also implied important risks to personal privacy. Indeed, while compromised passwords can be easily replaced and are not personally identifiable information(PII), biometric data is considered highly sensitive due to its personal nature, unique association with users, and the fact that compromised biometrics (biometric templates) cannot be revoked or replaced. Private biometrics have been developed to address this challenge. Private Biometrics provide the necessary biometric authentication while simultaneously minimizing user's privacy exposure through the use of one-way, fully homomorphic encryption. The Biometric Open Protocol Standard, IEEE 2410-2018, was updated in 2018 to include private biometrics and stated that the one-way fully homomorphic encrypted feature vectors, “...bring a new level of consumer privacy assurance by keeping biometric data encrypted both at rest and in transit.” The Biometric Open Protocol Standard (BOPS III) also noted a key benefit of private biometrics was the new standard allowed for simplification of the API since the biometric payload was always one-way encrypted and therefore had no need for key management.
Network Sovereignty Impact of VPNs Network_Sovereignty > Impact of VPNs In that example, by using VPNs, an Internet user in the United States could access banned material that is hosted in Amsterdam by accessing through a server, hosted in Amsterdam, to make it appear that the user is in Amsterdam, based on the IP address. Therefore, citizens have a way around network sovereignty, simply by accessing a different server through a VPN. That greatly limits how governments can enforce network sovereignty and protect their cyberspace borders. Essentially, there is no way that a government could prevent every citizen from accessing banned content by means such as VPNs.
Auxiliary normed space Sufficient conditions for a Banach disk Auxiliary_normed_space > Induced by a bounded disk – Banach disks > Sufficient conditions for a Banach disk The following are consequences of the above theorem: A sequentially complete bounded disk in a Hausdorff TVS is a Banach disk. Any disk in a Hausdorff TVS that is complete and bounded (e.g. compact) is a Banach disk. The closed unit ball in a Fréchet space is sequentially complete and thus a Banach disk.Suppose that D {\displaystyle D} is a bounded disk in a TVS X .
Interatomic force Van der Waals forces Instantaneous_dipole > Van der Waals forces The van der Waals forces arise from interaction between uncharged atoms or molecules, leading not only to such phenomena as the cohesion of condensed phases and physical absorption of gases, but also to a universal force of attraction between macroscopic bodies.
SraL RNA Summary SraL_RNA The SraL RNA ('sra' for small RNA), also known as RyjA, is a small non-coding RNA discovered in E. coli, and later in Salmonella Tiphimurium. This ncRNA was found to be expressed only in stationary phase. It may possibly play a role in Salmonella virulence.
List of prime numbers Lists of primes by type List_of_prime_numbers > Lists of primes by type Below are listed the first prime numbers of many named forms and types. More details are in the article for the name. n is a natural number (including 0) in the definitions.
Radio telegraphy Electrostatic and electromagnetic induction Radio_telegraphy > Non-radio methods > Electrostatic and electromagnetic induction Both electrostatic and electromagnetic induction were used to develop wireless telegraph systems that saw limited commercial application. In the United States, Thomas Edison, in the mid-1880s, patented an electromagnetic induction system he called "grasshopper telegraphy", which allowed telegraphic signals to jump the short distance between a running train and telegraph wires running parallel to the tracks. This system was successful technically but not economically, as there turned out to be little interest by train travelers in the use of an on-board telegraph service. During the Great Blizzard of 1888, this system was used to send and receive wireless messages from trains buried in snowdrifts.
Psychology of learning Information processing theories Psychology_of_learning > Psychology of learning theories > Information processing theories From the STM, some of this information is rehearsed and eventually encoded into the LTM where it is then stored permanently.Alternate models have been proposed in regards to how information is processed. For instance, some argue that there is one type of memory in the brain which has different levels of processing within it. Nevertheless, the classical model poses memory as dual memory (short-term and long-term) model.Another related theory is the dual-code theory which splits the brain processes into two systems: an imaginal system and a verbal system. The imaginal system primarily stores concrete events and objects while the verbal system stores more abstract information from language. This theory also allows for knowledge transfer within both systems as images, expressed through verbal language, can be encoded and placed into the imaginal system.While these theories can be traced back to gestalt psychology, many of these theories were influenced by the rise of technology, neuroscience, and communications.
Stepwise refinement Software development Top-down_design > Computer science > Software development Part of this section is from the Perl Design Patterns Book.In the software development process, the top–down and bottom–up approaches play a key role. Top–down approaches emphasize planning and a complete understanding of the system. It is inherent that no coding can begin until a sufficient level of detail has been reached in the design of at least some part of the system. Top–down approaches are implemented by attaching the stubs in place of the module.
Diffusion creep Principle Diffusion_creep > Principle The most stable state will be when all vacancies are evenly spread through the crystal. This principle follows from Fick's law: J x = − D x Δ C Δ x {\displaystyle J_{x}=-D_{x}{\frac {\Delta C}{\Delta x}}} In which Jx stands for the flux ("flow") of vacancies in direction x; Dx is a constant for the material in that direction and Δ C / Δ x {\displaystyle {\Delta C}/{\Delta x}} is the difference in concentration of vacancies in that direction. The law is valid for all principal directions in (x, y, z)-space, so the x in the formula can be exchanged for y or z. The result will be that they will become evenly distributed over the crystal, which will result in the highest mixing entropy.
Bridge strike Impacts Bridge_strike > Impacts The collapse was caused by a truck with an oversize load that was taller than the clearance above of the bridge. The bridge was a steel through-truss bridge with a "fracture-critical" design that has non-redundant load-bearing beams. An impact of the oversize load to multiple sway braces was enough to damage load-bearing members and caused a span to be collapsed, resulting in vehicles falling down to the river with three minor injuries.
Search engine indexing The forward index Search_engine_indexing > Indexing > The forward index The forward index stores a list of words for each document. The following is a simplified form of the forward index: The rationale behind developing a forward index is that as documents are parsed, it is better to intermediately store the words per document. The delineation enables asynchronous system processing, which partially circumvents the inverted index update bottleneck. The forward index is sorted to transform it to an inverted index.
Memory Span Digit-span Memory_Span > Digit-span Digit-span tasks are the most commonly used test for memory span, partially because performance on a digit-span task cannot be affected by factors such as semantics, frequency of appearance in daily life, complexity, etc.Verbal working memory is involved in many everyday tasks, such as remembering a friend's telephone number while entering it into a phone and understanding long and difficult sentences. Verbal working memory is also thought to be one of the elements underlying intelligence (often referred to as 'IQ,' meaning "intelligence quotient"); thus, the digit span task is a common component of many IQ tests, including the widely used Wechsler Adult Intelligence Scale (WAIS). Performance on the digit span task is also closely linked to language learning abilities; improving verbal memory capacities may therefore aid mastery of a new language.
Complex society Alternative theories Complex_society > Alternative theories Within the Axial Age, an increase in warfare intensity between the steppe peoples and the Persian and Chinese peoples forged the Achaemenid Persian empire and the Han Chinese empire, both complex societies. This theory has also been extended to explain the rise of complex states in Africa and Asia. The colonization of these places by European powers functioned as a meta-ethnic frontier in which warfare met the necessary level of intensity to forge the complex society.Another theory deals with the social evolution of altruism versus selfishness in the context of conflicting forces.
Matrix 2 of 5 Encoding Matrix_2_of_5 > Encoding W - wide black bar or white space. Narrow to wide components difference could be from 1/3 to 2/5.
Glossary of genetics (M–Z) O Glossary_of_genetics_(M–Z) > O Outrons are located entirely outside of the transcript's coding sequences, unlike introns. overexpression An abnormally high level of gene expression which results in an excessive number of copies of one or more gene products. Overexpression produces a pronounced gene-related phenotype.
Gottesman–Knill theorem Summary Gottesman–Knill_theorem In quantum computing, the Gottesman–Knill theorem is a theoretical result by Daniel Gottesman and Emanuel Knill that states that stabilizer circuits, circuits that only consist of gates from the normalizer of the qubit Pauli group, also called Clifford group, can be perfectly simulated in polynomial time on a probabilistic classical computer. The Clifford group can be generated solely by using CNOT, Hadamard, and phase gate S; and therefore stabilizer circuits can be constructed using only these gates. The reason for the speed up of quantum computers is not yet fully understood. The theorem proves that, for all quantum algorithms with a speed up that relies on entanglement which can be achieved with a CNOT and a Hadamard gate to produce entangled states, this kind of entanglement alone does not give any computing advantage. There exists a more efficient simulation of stabilizer circuits than the construction of the original publication with an implementation.The Gottesman–Knill theorem was published in a single author paper by Gottesman in which he credits Knill with the result through private communication.
Phagosome Maturation process Phagocytic_vacuole > Maturation process The composition of the phospholipid membrane also changes as the phagosome matures.Fusion may take minutes to hours depending on the contents of the phagosome; FcR or mannose receptor-mediated fusion last less than 30 minutes, but phagosomes containing latex beads may take several hours to fuse with lysosomes. It is suggested that the composition of the phagosome membrane affects the rate of maturation. Mycobacterium tuberculosis has a very hydrophobic cell wall, which is hypothesised to prevent membrane recycling and recruitment of fusion factors, so the phagosome does not fuse with lysosomes and the bacterium avoids degradation.Smaller lumenal molecules are transferred by fusion faster than larger molecules, which suggests that a small aqueous channel forms between the phagosome and other vesicles during "kiss-and-run", through which only limited exchange is allowed.
Q-Weibull distribution Summary Q-Weibull_distribution In statistics, the q-Weibull distribution is a probability distribution that generalizes the Weibull distribution and the Lomax distribution (Pareto Type II). It is one example of a Tsallis distribution.
Periodic Tales Reception Periodic_Tales > Reception The book received mixed but generally positive reviews from The Daily Telegraph, Kirkus Reviews, Publishers Weekly, and Science News. The Telegraph described the book as "a 400-page love letter to the chemical elements", and "an agreeable jumble of anecdote, reflection and information, rather than a source of understanding". Robert Buntrock, reviewing the book for the Journal of Chemical Education, found it to be more accurate and more enjoyable than The Disappearing Spoon by Sam Kean, a book with similar subject matter and audience published the year before. == References ==
Chip log History Knot_log > History All nautical instruments that measure the speed of a ship through water are known as logs. This nomenclature dates back to the days of sail, when sailors tossed a log attached to a rope knotted at regular intervals off the stern of a ship. Sailors counted the number of knots that passed through their hands in a given time to determine the ship's speed. Today, sailors and aircraft pilots still express speed in knots.
Sleep-disordered breathing Arterial Blood Gases Sleep_disordered_breathing > Physiology > Steady REM Sleep > Arterial Blood Gases Hypoxemia due to hypoventilation is noted in REM sleep but this is less well studied than NREM sleep. These changes are equal to or greater than NREM sleep
Multiple sclerosis research Lublin classification Multiple_sclerosis_research > Clinical courses redefinition > Lublin classification In 1996, the US National Multiple Sclerosis Society (NMSS) Advisory Committee on Clinical Trials in Multiple Sclerosis (ACCTMS) standardized four clinical courses for MS (Remitent-Recidivant, Secondary Progressive, Progressive-Relapsing and Primary progressive). Later, these were considered subtypes of the disease and this is known as the Lublin classification.Some reports state that those "types" were artificially made up for classifying RRMS as a separate disease. In this way, the number of patients in this group was low enough to get the interferon approved by the FDA under the orphan drugs act.Later revisions of this report removed the progressive-relapsing course and added CIS. Nevertheless, regulatory agencies often refer to unofficial subtypes in their recommendations, like "active SPMS" "highly active", or "rapidly progressive".
Biochemical cascade Blood cells Signalling_cascade > Cell-specific biochemical cascades > Blood cells The blood cells (erythrocytes, leukocytes and platelets) are produced by hematopoiesis. The erythrocytes have as main function the O2 delivery to the tissues, and this transfer occurs by diffusion and is determined by the O2 tension (PO2). The erythrocyte is able to feel the tissue need for O2 and cause a change in vascular caliber, through the pathway of ATP release, which requires an increase in cAMP, and are regulated by the phosphodiesterase (PDE). This pathway can be triggered via two mechanisms: physiological stimulus (like reduced O2 tension) and activation of the prostacyclin receptor (IPR).
Outer planet Composition Outer_planet > Structure and composition > Composition Jupiter and Saturn are composed mainly of gases with extremely low melting points and high vapor pressure, such as hydrogen, helium, and neon. Ices, like water, methane, ammonia, hydrogen sulfide, and carbon dioxide, have a melting points of up to a few hundred kelvins.

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