Split (1)

train · 253k rows

page_content stringlengths 51 3.15k
Pituitary disease Table Pituitary_neoplasm > Table The main disorders involving the pituitary gland are: Overproduction or underproduction of a pituitary hormone will affect the respective end-organ. For example, insufficient production (hyposecretion) of thyroid stimulating hormone (TSH) in the pituitary gland will cause hypothyroidism, while overproduction (hypersecretion) of TSH will cause hyperthyroidism. Thyroidisms caused by the pituitary gland are less common though, accounting for less than 10% of all hypothyroidism cases and much less than 1% of hyperthyroidism cases.
Flow (mathematics) Summary Flow_(geometry) In mathematics, a flow formalizes the idea of the motion of particles in a fluid. Flows are ubiquitous in science, including engineering and physics. The notion of flow is basic to the study of ordinary differential equations.
Carbidopa Pharmacology Carbidopa > Pharmacology Carbidopa inhibits aromatic-L-amino-acid decarboxylase (DOPA decarboxylase or DDC), an enzyme important in the biosynthesis of L-tryptophan to serotonin and in the biosynthesis of L-DOPA to dopamine (DA). DDC exists both outside of (body periphery) and within the confines of the blood–brain barrier. Carbidopa is used in the treatment of, among other diseases, Parkinson's disease (PD), a condition characterized by death of dopaminergic neurons in the substantia nigra. Increased dopamine availability may increase the effectiveness of the remaining neurons and alleviate symptoms for a time.
Metal film Failure modes Parallel_resistors > Failure modes Exceeding this voltage causes the resistor to degrade slowly reducing in resistance. The voltage dropped across large value resistors can be exceeded before the power dissipation reaches its limiting value. Since the maximum voltage specified for commonly encountered resistors is a few hundred volts, this is a problem only in applications where these voltages are encountered.
Constant phase element Summary Constant_phase_element In electronics, a constant phase element is an equivalent electrical circuit component that models the behaviour of a double layer, that is an imperfect capacitor (see double-layer capacitance). Constant phase elements are also used in equivalent circuit modeling and data fitting of electrochemical impedance spectroscopy data. A constant phase element also currently appears in modeling the imperfect dielectrics' behavior. The generalization in the fields of imperfect electrical resistances, capacitances, and inductances leads to the general "phasance" concept: http://fr.scribd.com/doc/71923015/The-Phasance-Concept
Pentatope number Properties Pentatopic_number > Properties This can be derived using telescoping series. ∑ n = 1 ∞ 4 ! n ( n + 1 ) ( n + 2 ) ( n + 3 ) = 4 3 .
L4 cache Specialized caches Instruction_cache > Cache hierarchy in a modern processor > Specialized caches Pipelined CPUs access memory from multiple points in the pipeline: instruction fetch, virtual-to-physical address translation, and data fetch (see classic RISC pipeline). The natural design is to use different physical caches for each of these points, so that no one physical resource has to be scheduled to service two points in the pipeline. Thus the pipeline naturally ends up with at least three separate caches (instruction, TLB, and data), each specialized to its particular role.
Autoimmune urticaria Summary Autoimmune_urticaria Autoimmune urticaria, also known as chronic autoimmune urticaria, is a type of chronic urticaria characterized by the presence of autoantibodies in the patient's immune system that target the body's own mast cells, leading to episodes of hives (urticaria). This immunologically distinct type of urticaria is considered autoimmune because the immune system, which normally protects the body from foreign organisms, mistakenly attacks the body's own cells, causing inflammation and other symptoms.The condition is chronic, meaning it persists for more than six weeks, and can last for many years. Symptoms include recurrent episodes of hives, which are red, itchy, and swollen areas on the skin. These episodes can be triggered by various factors, including heat, stress, or for no identifiable reason.Autoimmune urticaria is a relatively rare condition, affecting a small percentage of the population.
Protein nuclear magnetic resonance Automation of the process Protein_NMR > Automation of the process Most progress has been achieved for the task of automated NOE assignment. So far, only the FLYA and the UNIO approach were proposed to perform the entire protein NMR structure determination process in an automated manner without any human intervention.
Proteasome inhibitor Mechanism Proteasome_inhibitor > Mechanism Multiple mechanisms are likely to be involved, but proteasome inhibition may prevent degradation of pro-apoptotic factors such as the p53 protein, permitting activation of programmed cell death in neoplastic cells dependent upon suppression of pro-apoptotic pathways. For example, bortezomib causes a rapid and dramatic change in the levels of intracellular peptides.
Live streaming Metrics Live_video_streaming > Metrics With livestreaming becoming a financially viable market, particularly for esports, streamers and organizations representing them have looked for metrics to quantify the viewership of streams as to be able to determine pricing for advertisers. Metrics like maximum number of concurrent viewers, or number of subscribers do not readily account for how long a viewer may stay to watch a stream. The most common metric is the "Average Minute Audience" (AMA), which is obtained by taking the total minutes watched by all viewers on the stream during the streamed event and for 24 hours afterwards, divided by the number of minutes that were broadcast.
Protein chemistry Computational biology Protein_chemistry > Areas of Research > Computational biology Computational biology involves the development and application of data-analytical and theoretical methods, mathematical modeling and computational simulation techniques to the study of biological, ecological, behavioral, and social systems. The field is broadly defined and includes foundations in biology, applied mathematics, statistics, biochemistry, chemistry, biophysics, molecular biology, genetics, genomics, computer science and evolution. Computational biology has become an important part of developing emerging technologies for the field of biology. Molecular modelling encompasses all methods, theoretical and computational, used to model or mimic the behaviour of molecules. The methods are used in the fields of computational chemistry, drug design, computational biology and materials science to study molecular systems ranging from small chemical systems to large biological molecules and material assemblies.
Astronomical filter Color filters Solar_filter > Color filters It was first manufactured by Kodak in 1909.Professional filters are also colored, but their bandpass centers are placed around other midpoints (such as in the UBVRI and Cousins systems). Some of common color filters and their uses are: Chromatic aberration filters: Used for reduction of the purplish halo, caused by chromatic aberration of refracting telescopes. Such halo can obscure features of bright objects, especially Moon and planets.
Information metabolism Reception Information_metabolism > Reception The work upon it was interrupted by his illness and death. Some researchers took his work and developed their own theories based on it. Kokoszka used the conception of information metabolism as the basis of his model of the states of consciousness. Struzik proposed that information metabolism theory may be used as an extension to Brillouin's negentropy principle of information.Based on the Kępiński's work and Jungian typology, Lithuanian economist Augustinavičiūtė proposed her pseudoscientific theory of information metabolism in human mind and society, known as socionics.
Child psychology Main research methods Child_psychologist > Research methods and designs > Main research methods Developmental psychology employs many of the research methods used in other areas of psychology. However, infants and children cannot be tested in the same ways as adults, so different methods are often used to study their development. Developmental psychologists have a number of methods to study changes in individuals over time. Common research methods include systematic observation, including naturalistic observation or structured observation; self-reports, which could be clinical interviews or structured interviews; clinical or case study method; and ethnography or participant observation.
Gastrointestinal cancer Large intestine Gastrointestinal_cancer > Field defects > Large intestine When a segment of the large intestine, containing a cancer, is removed, the area adjacent to the cancer (and removed with it) may show additional neoplasia in the form of polyps (see image). This is visual evidence of a field defect. Some of these polyps may be premalignant neoplastic tumors. As shown by Hofstad et al., when polyps are allowed to remain in the colon and are observed for three years, about 40% of polyps are seen to grow larger, likely progressing towards cancer. Luo et al. summarized the substantial body of evidence that field cancerization occurs in the colon, often due to aberrant DNA methylation.
Richard Jeffrey Radical probabilism Richard_Jeffrey > Philosophical work > Radical probabilism Jeffrey famously rejected Lewis' dictum and quipped, "It's probabilities all the way down." He called this position radical probabilism. In this case Bayes' rule isn't able to capture a mere subjective change in the probability of some critical fact.
Algebraic function Summary Algebraic_functions A composition of transcendental functions can give an algebraic function: f ( x ) = cos ⁡ arcsin ⁡ x = 1 − x 2 {\displaystyle f(x)=\cos \arcsin x={\sqrt {1-x^{2}}}} . As a polynomial equation of degree n has up to n roots (and exactly n roots over an algebraically closed field, such as the complex numbers), a polynomial equation does not implicitly define a single function, but up to n functions, sometimes also called branches. Consider for example the equation of the unit circle: y 2 + x 2 = 1.
Glossary of engineering: A–L H Glossary_of_engineering:_A–L > H Some materials (e.g. metals) are harder than others (e.g. plastics, wood). Macroscopic hardness is generally characterized by strong intermolecular bonds, but the behavior of solid materials under force is complex; therefore, there are different measurements of hardness: scratch hardness, indentation hardness, and rebound hardness. Hardness is dependent on ductility, elastic stiffness, plasticity, strain, strength, toughness, viscoelasticity, and viscosity.
Glossary of environmental science P Glossary_of_environmental_science > P photosynthesis – the transformation of radiant energy to chemical energy by plants; the manufacture by plants of carbohydrates from carbon dioxide and water. The reaction is driven by energy from sunlight, catalysed by chlorophyll and releases oxygen as a byproduct. The capture of the Sun's energy (primary production) to power all life on Earth (consumption).
Kolmogorov's generalized criterion Example Kolmogorov's_criterion > Discrete-time Markov chains > Example Consider this figure depicting a section of a Markov chain with states i, j, k and l and the corresponding transition probabilities. Here Kolmogorov's criterion implies that the product of probabilities when traversing through any closed loop must be equal, so the product around the loop i to j to l to k returning to i must be equal to the loop the other way round, p i j p j l p l k p k i = p i k p k l p l j p j i . {\displaystyle p_{ij}p_{jl}p_{lk}p_{ki}=p_{ik}p_{kl}p_{lj}p_{ji}.}
Ageing Summary Ageing Ageing increases the risk of human diseases such as cancer, Alzheimer's disease, diabetes, cardiovascular disease, stroke and many more. Of the roughly 150,000 people who die each day across the globe, about two-thirds die from age-related causes. Current ageing theories are assigned to the damage concept, whereby the accumulation of damage (such as DNA oxidation) may cause biological systems to fail, or to the programmed ageing concept, whereby the internal processes (epigenetic maintenance such as DNA methylation) inherently may cause ageing.
Glossary of structural engineering A Glossary_of_structural_engineering > A In addition to the cumulative magnitudes of these intermolecular forces, there are also certain emergent mechanical effects. Aggregate (composite) – is the component of a composite material that resists compressive stress and provides bulk to the composite material. For efficient filling, aggregate should be much smaller than the finished item, but have a wide variety of sizes.
Aminoadipate aminotransferase Summary Aminoadipate_aminotransferase In enzymology, a 2-aminoadipate transaminase (EC 2.6.1.39) is an enzyme that catalyzes the chemical reaction L-2-aminoadipate + 2-oxoglutarate ⇌ {\displaystyle \rightleftharpoons } 2-oxoadipate + L-glutamateThus, the two substrates of this enzyme are L-2-aminoadipate and 2-oxoglutarate, whereas its two products are 2-oxoadipate and L-glutamate. This enzyme belongs to the family of transferases, specifically the transaminases, which transfer nitrogenous groups. The systematic name of this enzyme class is L-2-aminoadipate:2-oxoglutarate aminotransferase.
Application Portability Profile Overview Application_Portability_Profile > Overview The NIST developed such an infrastructure, and named it Open System Environment (OSE).An Open System Environment (OSE) encompasses the functionality needed to provide interoperability, portability, and scalability of computerized applications across networks of heterogeneous, multi-vendor hardware/software/communications platforms. The Open System Environment forms an extensible framework that allows services, interfaces, protocols, and supporting data formats to be defined in terms of nonproprietary specifications that evolve through open (public), consensus-based forums.Complementary to the Open System Environment is the Application Portability Profile standard.
Pulmonary shunt Pathophysiology Pulmonary_shunt > Pathophysiology This vasoconstriction is triggered by a smooth muscle reflex, as a consequence of the low oxygen concentration itself. Blood is then redirected away from this area, which poorly matches ventilation and perfusion, to areas which are being ventilated. A decrease in perfusion relative to ventilation (as occurs in pulmonary embolism, for example) is an example of increased dead space.
Scale ratio In maps Scale_ratio > In maps Map scales require careful discussion. A town plan may be constructed as an exact scale drawing, but for larger areas a map projection is necessary and no projection can represent the Earth's surface at a uniform scale. In general the scale of a projection depends on position and direction. The variation of scale may be considerable in small scale maps which may cover the globe.
Kepler (novel) Summary Kepler_(novel) Kepler is a novel by John Banville, first published in 1981. In Kepler Banville recreates Prague despite never having been there when he wrote it. A historical novel, it won the 1981 Guardian Fiction Prize. == References ==
Temperature scale Empirical scales Scale_of_temperature > Empirical scales Empirical scales are based on the measurement of physical parameters that express the property of interest to be measured through some formal, most commonly a simple linear, functional relationship. For the measurement of temperature, the formal definition of thermal equilibrium in terms of the thermodynamic coordinate spaces of thermodynamic systems, expressed in the zeroth law of thermodynamics, provides the framework to measure temperature. All temperature scales, including the modern thermodynamic temperature scale used in the International System of Units, are calibrated according to thermal properties of a particular substance or device. Typically, this is established by fixing two well-defined temperature points and defining temperature increments via a linear function of the response of the thermometric device.
Tibor Šalát Academic papers Tibor_Šalát > Academic papers Tibor Šalát; S. James Taylor; János T. Tóth (1998). "Radii of Convergence of Power Series". Real Analysis Exchange.
Data deluge Challenges Information_explosion > Challenges Even though the abundance of information can be beneficial in several levels, some problems may be of concern such as privacy, legal and ethical guidelines, filtering and data accuracy. Filtering refers to finding useful information in the middle of so much data, which relates to the job of data scientists. A typical example of a necessity of data filtering (data mining) is in healthcare since in the next years is due to have EHRs (Electronic Health Records) of patients available. With so much information available, the doctors will need to be able to identify patterns and select important data for the diagnosis of the patient.
Mobile cloud computing MCC research groups and activities Mobile_cloud_computing > MCC research groups and activities The MCN project was launched in November 2012 for the period of 36 month. The project was coordinated by SAP Research and the ICCLab at the Zurich University of Applied Science. In total 19 top-tier partners from industry and academia established the very first vision of Mobile Cloud Computing. The project was primarily motivated by an ongoing transformation that drives the convergence between the Mobile Communications and Cloud Computing industry enabled by the Internet and is considered the very first pioneer in the area of Network Function Virtualization.
Evolution of metal ions in biological systems Iron Evolution_of_metal_ions_in_biological_systems > Metal ions > Iron In proteins, it is found in a variety of sites and cofactors, including, for instance, haem groups, Fe–O–Fe sites, and iron–sulfur clusters. The prevalence of iron is apparently due to the large availability of Fe(II) in the initial evolution of living organisms, before the rise of photosynthesis and an increase in atmospheric oxygen levels which resulted in the precipitation of iron in the environment as Fe(OH)3. It has flexible redox properties because such properties are sensitive to ligand coordination, including geometry.
Tacticity Atactic polymers Tacticity > Polymers > Atactic polymers A good example is polystyrene (PS). If a special catalyst is used in its synthesis it is possible to obtain the syndiotactic version of this polymer, but most industrial polystyrene produced is atactic. The two materials have very different properties because the irregular structure of the atactic version makes it impossible for the polymer chains to stack in a regular fashion. The result is that, whereas syndiotactic PS is a semicrystalline material, the more common atactic version cannot crystallize and forms a glass instead. This example is quite general in that many polymers of economic importance are atactic glass formers.
Control (video game) Summary Control_(video_game) The environments of the Oldest House are designed in the brutalist architecture style, common for many government buildings created during the Cold War era, which served as a setting to show off the game's destructive environmental systems. The core game includes many allusions to Alan Wake, one of Remedy's prior games with similar themes of the paranormal, and Control's AWE expansion is a crossover between these two series, which Remedy said forms part of the Remedy Connected Universe. Control was one of the first games released to take advantage of real-time ray tracing built into the hardware of newer video cards.
SIMD lanes Advantages Single_instruction,_multiple_data > Advantages Another advantage is that the instruction operates on all loaded data in a single operation. In other words, if the SIMD system works by loading up eight data points at once, the add operation being applied to the data will happen to all eight values at the same time. This parallelism is separate from the parallelism provided by a superscalar processor; the eight values are processed in parallel even on a non-superscalar processor, and a superscalar processor may be able to perform multiple SIMD operations in parallel.
Contour currents Depositional Processes Contour_currents > Depositional Processes Since contour currents generally flow at speed of 2–20 cm/s, their capacity to carry sediments is limited to fine grain particles already in suspension. Redistribution of sediments by contour currents have, however, been reported as evidenced by the sea floor morphological features parallel to regional isobaths. Turbidity currents, on the other hand, flow down slope across regional isobaths and are mainly responsible for supplying terrigenous sediment across continental margins to deep-water environments, such as continental rise, where fine particles are further carried in suspension by contour currents. The joint depositional processes of the two current systems contribute to the dominant factors influencing the morphology of the lower continental margins. == References ==
CRISPR interference Repression CRISPR_interference > Transcriptional regulation > Repression CRISPRi can sterically repress transcription by blocking either transcriptional initiation or elongation. This is accomplished by designing sgRNA complementary to the promoter or the exonic sequences. The level of transcriptional repression with a target within the coding sequence is strand-specific. Depending on the nature of the CRISPR effector, either the template or non-template strand leads to stronger repression.
Negative dynamic resistance Definitions Negative_differential_resistance > Definitions Devices of this type can amplify signals, and are what is usually meant by the term "negative resistance".Negative resistance, like positive resistance, is measured in ohms. Conductance is the reciprocal of resistance. It is measured in siemens (formerly mho) which is the conductance of a resistor with a resistance of one ohm. Each type of resistance defined above has a corresponding conductance Static conductance Differential conductance It can be seen that the conductance has the same sign as its corresponding resistance: a negative resistance will have a negative conductance while a positive resistance will have a positive conductance.
Solipsism Varieties Solipsism > Varieties There are varying degrees of solipsism that parallel the varying degrees of skepticism:
Polyclonal B cell response Antigen presentation Polyclonal_response > B cell response > Antigen presentation After the processed antigen (peptide) is complexed to the MHC molecule, they both migrate together to the cell membrane, where they are exhibited (elaborated) as a complex that can be recognized by the CD 4+ (T helper cell) – a type of white blood cell. This is known as antigen presentation. However, the epitopes (conformational epitopes) that are recognized by the B cell prior to their digestion may not be the same as that presented to the T helper cell. Additionally, a B cell may present different peptides complexed to different MHC-II molecules.
Automation Master Multimode Models Automation_Master > Automation Master Operating Modes > Multimode Models Real time simulation allows multiple mode models to be built. A multiple mode model can be operated in either simulation, emulation, or monitor modes by simply invoking the simulator with a different configuration file. Multiple mode models are created by separating the model of the system control strategy from the model of the physical components. There are two distinct elements in a simulation model of an automated system.
Complications of diabetes mellitus Vitamins Complications_of_diabetes_mellitus > Management > Vitamins Finally, vitamin D may reduce the risk of vascular complications by modulating lipid profile. Antioxidants may have beneficial effects on diabetic complications by reducing blood pressure, attenuating oxidative stress and inflammatory biomarkers, improving lipid metabolism, insulin-mediated glucose disposal, and by enhancing endothelial function.Vitamin C has been proposed to induce beneficial effects by two other mechanisms. It may replace glucose in many chemical reactions due to its similarity in structure, may prevent the non-enzymatic glycosylation of proteins, and might reduce glycated hemoglobin (HbA1c) levels. Secondly, vitamin C has also been suggested to play a role in lipid regulation as a controlling catabolism of cholesterol to bile acid.
Dynamic list Related data structures Dynamic_list > Related data structures A hash table may use linked lists to store the chains of items that hash to the same position in the hash table. A heap shares some of the ordering properties of a linked list, but is almost always implemented using an array. Instead of references from node to node, the next and previous data indexes are calculated using the current data's index. A self-organizing list rearranges its nodes based on some heuristic which reduces search times for data retrieval by keeping commonly accessed nodes at the head of the list.
Approximate Bayesian Computation Small number of models Approximate_Bayesian_Computation > Pitfalls and remedies > General risks in statistical inference exacerbated in ABC > Small number of models Although more robust procedures for a priori model choice and formulation would be beneficial, there is no one-size-fits-all strategy for model development in statistics: sensible characterization of complex systems will always necessitate a great deal of detective work and use of expert knowledge from the problem domain. Some opponents of ABC contend that since only few models—subjectively chosen and probably all wrong—can be realistically considered, ABC analyses provide only limited insight. However, there is an important distinction between identifying a plausible null hypothesis and assessing the relative fit of alternative hypotheses. Since useful null hypotheses, that potentially hold true, can extremely seldom be put forward in the context of complex models, predictive ability of statistical models as explanations of complex phenomena is far more important than the test of a statistical null hypothesis in this context. It is also common to average over the investigated models, weighted based on their relative plausibility, to infer model features (e.g., parameter values) and to make predictions.
Natural immunity Artificially acquired Natural_immunity > Active immunity > Artificially acquired Subunit, recombinant, polysaccharide, and conjugate vaccines are composed of small fragments or pieces from a pathogenic (disease-causing) organism. A characteristic example is the subunit vaccine against Hepatitis B virus.In addition, there are some newer types of vaccines in use: Outer Membrane Vesicle (OMV) vaccines contain the outer membrane of a bacterium without any of its internal components or genetic material. Thus, ideally, they stimulate an immune response effective against the original bacteria without the risk of an infection.
Constructive set theory Bishop style set theory Constructive_set_theory > Sorted theories > Bishop style set theory Set theory in the flavor of Errett Bishop's constructivist school mirrors that of Myhill, but is set up in a way that sets come equipped with relations that govern their discreteness. Commonly, Dependent Choice is adopted. A lot of analysis and module theory has been developed in this context.
Ether complex Summary Transition_metal_ether_complex In chemistry, a transition metal ether complex is a coordination complex consisting of a transition metal bonded to one or more ether ligand. The inventory of complexes is extensive. Common ether ligands are diethyl ether and tetrahydrofuran. Common chelating ether ligands include the glymes, dimethoxyethane (dme) and diglyme, and the crown ethers. Being lipophilic, metal-ether complexes often exhibit solubility in organic solvents, a property of interest in synthetic chemistry. In contrast, the di-ether 1,4-dioxane is generally a bridging ligand.
Generalized anxiety disorder Serotonin norepinephrine reuptake inhibitors Generalized_anxiety_disorder > Treatment > Pharmacotherapy > Serotonin norepinephrine reuptake inhibitors In comparison to SSRIs, the SNRIs have a higher prevalence of the side effects of insomnia, dry mouth, nausea and high blood pressure. Both SNRIs have the potential for discontinuation syndrome after abrupt cessation, which can precipitate symptoms including motor disturbances and anxiety and may require tapering. Like other serotonergic agents, SNRIs have the potential to cause serotonin syndrome, a potentially fatal systemic response to serotonergic excess that causes symptoms including agitation, restlessness, confusion, tachycardia, hypertension, mydriasis, ataxia, myoclonus, muscle rigidity, diaphoresis, diarrhea, headache, shivering, goose bumps, high fever, seizures, arrhythmia and unconsciousness. SNRIs like SSRIs carry a black box warning for suicidal ideation, but it is generally considered that the risk of suicide in untreated depression is far higher than the risk of suicide when depression is properly treated.
Activity cycle diagram Implementation Activity_cycle_diagram > Implementation In activity-based modeling, the dynamics of system is represented as an ACD which is a network model of the logical and temporal relationships among the activities. An ACD is easily implemented with the activity scanning method of simulation execution.
Strong ground motion Correlation with the Mercalli scale Shake_map > Correlation with the Mercalli scale The United States Geological Survey created the Instrumental Intensity scale, which maps peak ground velocity on an intensity scale comparable to the felt Mercalli scale. Seismologists all across the world use these values to construct ShakeMaps.
Life support system Linear acceleration Life-support_system > Human physiological and metabolic needs > Gravity > Linear acceleration If a spacecraft's engines could produce thrust continuously on the outbound trip with a thrust level equal to the mass of the ship, it would continuously accelerate at the rate of 32.2 feet per second (9.8 m/s) per second, and the crew would experience a pull toward the ship's aft bulkhead at normal Earth gravity (one g). The effect is proportional to the rate of acceleration. When the ship reaches the halfway point, it would turn around and produce thrust in the retrograde direction to slow down.
Spectral estimation of multidimensional signals Basic Concepts Multidimensional_spectral_estimation > Basic Concepts In a single dimensional case, a signal is characterized by an amplitude and a time scale. The basic concepts involved in spectral estimation include autocorrelation, multi-D Fourier transform, mean square error and entropy. When it comes to multidimensional signals, there are two main approaches: use a bank of filters or estimate the parameters of the random process in order to estimate the power spectrum.
Cache misses Disk cache Write-back_cache > Software caches > Disk cache However, high-end disk controllers often have their own on-board cache of the hard disk drive's data blocks. Finally, a fast local hard disk drive can also cache information held on even slower data storage devices, such as remote servers (web cache) or local tape drives or optical jukeboxes; such a scheme is the main concept of hierarchical storage management. Also, fast flash-based solid-state drives (SSDs) can be used as caches for slower rotational-media hard disk drives, working together as hybrid drives or solid-state hybrid drives (SSHDs).
Anaerobic respiration Ecological importance Anaerobic_respiration > Ecological importance Anaerobic respiration is a critical component of the global nitrogen, iron, sulfur, and carbon cycles through the reduction of the oxyanions of nitrogen, sulfur, and carbon to more-reduced compounds. The biogeochemical cycling of these compounds, which depends upon anaerobic respiration, significantly impacts the carbon cycle and global warming. Anaerobic respiration occurs in many environments, including freshwater and marine sediments, soil, subsurface aquifers, deep subsurface environments, and biofilms. Even environments, such as soil, that contain oxygen also have micro-environments that lack oxygen due to the slow diffusion characteristics of oxygen gas.
General position Abstractly: configuration spaces General_position > Abstractly: configuration spaces In very abstract terms, general position is a discussion of generic properties of a configuration space; in this context one means properties that hold on the generic point of a configuration space, or equivalently on a Zariski-open set. This notion coincides with the measure theoretic notion of generic, meaning almost everywhere on the configuration space, or equivalently that points chosen at random will almost surely (with probability 1) be in general position.
Generative art Live coding Generative_art > Types > Live coding Generative systems may be modified while they operate, for example by using interactive programming environments such as SuperCollider, Fluxus and TidalCycles, including patching environments such as Max/MSP, Pure Data and vvvv. This is a standard approach to programming by artists, but may also be used to create live music and/or video by manipulating generative systems on stage, a performance practice that has become known as live coding. As with many examples of software art, because live coding emphasizes human authorship rather than autonomy, it may be considered in opposition to generative art.
Eukaryotic large ribosomal subunit (60S) Overall structure Eukaryotic_large_ribosomal_subunit_(60S) > Overall structure The rRNA core is decorated with dozens of proteins. In the figure "Crystal Structure of the Eukaryotic 60S Ribosomal Subunit from T. thermophila", the ribosomal RNA core is represented as a grey tube and expansion segments are shown in red. Proteins which have homologs in eukaryotes, archaea and bacteria are shown as blue ribbons. Proteins shared only between eukaryotes and archaea are shown as orange ribbons and proteins specific to eukaryotes are shown as red ribbons.
Control coefficient (biochemistry) Relationship to rate-limiting steps Control_coefficient_(biochemistry) > Formal Definition > Relationship to rate-limiting steps The flux control coefficient, instead, measures how much influence a given step has on the steady-state flux. A step with a high flux control coefficient means that changing the activity of the step (by changing the expression level of the enzyme) will have a large effect on the steady-state flux through the pathway and vice versa. Historically the concept of the rate-limiting steps was also related to the notion of the master step. However, this drew much criticism due to a misunderstanding of the concept of the steady-state.
PF INET Server Berkeley_Sockets > Client-server example using TCP > Server This blocks the process until an incoming connection is received, and returns a socket descriptor for the accepted connection. The initial descriptor remains a listening descriptor, and accept() can be called again at any time with this socket, until it is closed. Communicating with the remote host with the API functions send() and recv(), as well as with the general-purpose functions write() and read(). Closing each socket that was opened after use with function close()The following program creates a TCP server listening on port number 1100:
Hub and spokes architecture Summary Hub_and_spokes_architecture Network architecture is the design of a computer network. It is a framework for the specification of a network's physical components and their functional organization and configuration, its operational principles and procedures, as well as communication protocols used. In telecommunication, the specification of a network architecture may also include a detailed description of products and services delivered via a communications network, as well as detailed rate and billing structures under which services are compensated. The network architecture of the Internet is predominantly expressed by its use of the Internet protocol suite, rather than a specific model for interconnecting networks or nodes in the network, or the usage of specific types of hardware links.
Computational complexity Complexity as a function of input size Context_of_computational_complexity > Complexity as a function of input size It is impossible to count the number of steps of an algorithm on all possible inputs. As the complexity generally increases with the size of the input, the complexity is typically expressed as a function of the size n (in bits) of the input, and therefore, the complexity is a function of n. However, the complexity of an algorithm may vary dramatically for different inputs of the same size. Therefore, several complexity functions are commonly used. The worst-case complexity is the maximum of the complexity over all inputs of size n, and the average-case complexity is the average of the complexity over all inputs of size n (this makes sense, as the number of possible inputs of a given size is finite). Generally, when "complexity" is used without being further specified, this is the worst-case time complexity that is considered.
Solar powered Energy storage methods Solar_powered > Energy storage methods Thermal mass systems can store solar energy in the form of heat at domestically useful temperatures for daily or interseasonal durations. Thermal storage systems generally use readily available materials with high specific heat capacities such as water, earth and stone. Well-designed systems can lower peak demand, shift time-of-use to off-peak hours and reduce overall heating and cooling requirements.Phase change materials such as paraffin wax and Glauber's salt are another thermal storage medium.
Resistance gene Summary Resistance_gene A resistance gene is any gene producing resistance against an agent. This gene may produce: Drug resistanceAntimicrobial resistance Multiple drug resistanceDisease resistancePlant disease resistanceGene-for-gene relationshipTolerance to infectionsPesticide resistanceAcaricide resistance Insecticide resistancePyrethroid resistance Larvicide resistanceHerbicide resistance Fungicide resistance Nematicide resistance Anthelmintic/vermicide resistanceResistance to parasitesResistance to mites Resistance to ticks Resistance to herbivores - plant defense against herbivory
Quadratic set Summary Quadratic_set In mathematics, a quadratic set is a set of points in a projective space that bears the same essential incidence properties as a quadric (conic section in a projective plane, sphere or cone or hyperboloid in a projective space).
Josephson voltage standard Uncertainty Josephson_voltage_standard > Uncertainty Typically, the total uncertainty contribution of a Josephson system in a measurement averaging time of a few minutes is a few nanovolts. Since the most common use of these systems is the calibration of Zener standards with a noise level of 50–100 nV, the contribution of the Josephson system is negligible. Table 2. Potential sources of error and uncertainty for a Josephson standard
BOSH (software) Architecture BOSH_(software) > Architecture A BOSH installation is made of several separate components that can possibly be split across different VMs or containers: A Director that is the “brain” of the server The director database, made of a PostgreSQL instance, a Redis instance and a Blobstore for storing compiled packages and jobs A Health Monitor that keeps track of instances (VMs or containers) status Many BOSH agents, one on each deployed instance A NATS message bus for connecting the Director, the Health Monitor, and all the deployed BOSH agents A CPI (Cloud Provider Interface), which is just an executable binary conforming to some specific APIA BOSH managed environment usually centers around the Director deployed on a VM.
Optimizing compilers Loop optimizations Compiler_analysis > Specific techniques > Loop optimizations Additionally, if the comparison number exceeds the size of word of the platform, in standard loop order, multiple instructions would need to be executed in order to evaluate the comparison, which is not the case with loop reversal.Loop unrolling Unrolling duplicates the body of the loop multiple times, in order to decrease the number of times the loop condition is tested and the number of jumps, which hurt performance by impairing the instruction pipeline. A "fewer jumps" optimization. Completely unrolling a loop eliminates all overhead, but requires that the number of iterations be known at compile time.Loop splitting Loop splitting attempts to simplify a loop or eliminate dependencies by breaking it into multiple loops which have the same bodies but iterate over different contiguous portions of the index range. A useful special case is loop peeling, which can simplify a loop with a problematic first iteration by performing that iteration separately before entering the loop.Loop unswitching Unswitching moves a conditional from inside a loop to outside the loop by duplicating the loop's body inside each of the if and else clauses of the conditional.Software pipelining The loop is restructured in such a way that work done in an iteration is split into several parts and done over several iterations. In a tight loop, this technique hides the latency between loading and using values.Automatic parallelization A loop is converted into multi-threaded or vectorized (or even both) code in order to utilize multiple processors simultaneously in a shared-memory multiprocessor (SMP) machine, including multi-core machines.
Secure Erase Risks posed by inadequate data-set sanitization Secure_Erase > Risks posed by inadequate data-set sanitization It detects the general trend of data and discards any data that strays and it’s able to target anomalies even when inserted as a group. In general, data sanitization techniques use algorithms to detect anomalies and remove any suspicious points that may be poisoned data or sensitive information. Furthermore, data sanitization methods may remove useful, non-sensitive information, which then renders the sanitized dataset less useful and altered from the original.
Mechanical–electrical analogies Summary Mechanical-electrical_analogies By itself, that is not enough to fully define the analogy, a second variable must be chosen. A common choice is to make pairs of power conjugate variables analogous.
Crowd simulation Military Crowd_simulation > Real world applications > Military Being that crowd simulations are so prevalent in use for public planning and general order with regards to chaotic situations, many applications can be drawn for governmental and military simulations. Crowd modeling is essential in police and military simulation in order to train officers and soldiers to deal with mass gatherings of people. Not only do offensive combatants prove to be difficult for these individuals to handle, but noncombatant crowds play significant roles in making these aggressive situations more out of control. Game technology is used in order to simulate these situations for soldiers and technicians to practice their skills.
Domain name Domain name space DNS_domain > Domain name space Today, the Internet Corporation for Assigned Names and Numbers (ICANN) manages the top-level development and architecture of the Internet domain name space. It authorizes domain name registrars, through which domain names may be registered and reassigned. The domain name space consists of a tree of domain names. Each node in the tree holds information associated with the domain name. The tree sub-divides into zones beginning at the DNS root zone.
Electromagnetic mass Mass of the fictitious electromagnetic fluid Electromagnetic_mass > Inertia of energy and radiation paradoxes > Mass of the fictitious electromagnetic fluid Finally he repeats this exact problem of "Newton's principle" from 1904 again in 1908 publication in his section on "the principle of reaction" he notes that the actions of radiation pressure cannot be tied solely to matter in light of Fizeau's proof that the Hertz notion of total ether drag is untenable. This, he clarifies in the next section in his own explanation of Mass–energy equivalence: Well, the deformation of the electrons, a deformation which depends upon their velocity, will modify the distribution of the electricity upon their surface, consequently the intensity of the convection current they produce, consequently the laws according to which the self-induction of this current will vary as a function of the velocity. At this price, the compensation will be perfect and will conform to the requirements of the principle of relativity, but only upon two conditions: 1° That the positive electrons have no real mass, but only a fictitious electromagnetic mass; or at least that their real mass, if it exists, is not constant and varies with the velocity according to the same laws as their fictitious mass; 2° That all forces are of electromagnetic origin, or at least that they vary with the velocity according to the same laws as the forces of electromagnetic origin.
Three-surface aircraft Pitch equilibrium Three-surface_aircraft > Reduced surface area design > Pitch equilibrium On a three-surface aircraft, the pitch trim forces can be shared, as needed in flight, between the foreplane and tailplane. Equilibrium can be achieved with lift from the foreplane rather than downforce from the tailplane.
Passively safe Terminology Passively_safe > Terminology Reactors could be fitted with a hydraulic safety system component that increases the inflow pressure of coolant (esp. water) in response to increased outflow pressure of the moderator and coolant without control system intervention. Such reactors would be described as fitted with such a passive safety component that could – if so designed – render in a reactor a negative void coefficient of reactivity, regardless of the operational property of the reactor in which it is fitted.
DNA damage theory of aging Menopause Genetic_mutation_theory_of_aging > Menopause The role of declining ATM-Mediated DNA double strand DNA break (DSB) repair in oocyte aging was first proposed by Kutluk Oktay, MD, PhD based on his observations that women with BRCA mutations produced fewer oocytes in response to ovarian stimulation repair. His laboratory has further studied this hypothesis and provided an explanation for the decline in ovarian reserve with age. They showed that as women age, double-strand breaks accumulate in the DNA of their primordial follicles.
Statistical energy analysis Summary Statistical_energy_analysis Statistical energy analysis (SEA) is a method for predicting the transmission of sound and vibration through complex structural acoustic systems. The method is particularly well suited for quick system level response predictions at the early design stage of a product, and for predicting responses at higher frequencies. In SEA a system is represented in terms of a number of coupled subsystems and a set of linear equations are derived that describe the input, storage, transmission and dissipation of energy within each subsystem. The parameters in the SEA equations are typically obtained by making certain statistical assumptions about the local dynamic properties of each subsystem (similar to assumptions made in room acoustics and statistical mechanics). These assumptions significantly simplify the analysis and make it possible to analyze the response of systems that are often too complex to analyze using other methods (such as finite element and boundary element methods).
Statistical proof Bayes theorem Statistical_proof > Bayes theorem Bayesian statistics are based on a different philosophical approach for proof of inference. The mathematical formula for Bayes's theorem is: P r = P r × P r P r {\displaystyle Pr={\frac {Pr\times Pr}{Pr}}} The formula is read as the probability of the parameter (or hypothesis =h, as used in the notation on axioms) “given” the data (or empirical observation), where the horizontal bar refers to "given". The right hand side of the formula calculates the prior probability of a statistical model (Pr ) with the likelihood (Pr ) to produce a posterior probability distribution of the parameter (Pr ). The posterior probability is the likelihood that the parameter is correct given the observed data or samples statistics.
Küpfmüller's uncertainty principle Summary Küpfmüller's_uncertainty_principle Küpfmüller's uncertainty principle by Karl Küpfmüller in the year 1924 states that the relation of the rise time of a bandlimited signal to its bandwidth is a constant. Δ f Δ t ≥ k {\displaystyle \Delta f\Delta t\geq k} with k {\displaystyle k} either 1 {\displaystyle 1} or 1 2 {\displaystyle {\frac {1}{2}}}
Global conveyor belt Other sources Thermohaline_circulation > Other sources Apel, JR (1987). Principles of Ocean Physics. Academic Press. ISBN 0-12-058866-8.
Circulating free DNA Summary Circulating_free_DNA Cell‐free DNA (cfDNA) is present in the circulating plasma and in other body fluids.The release of cfDNA into the bloodstream appears by different reasons, including apoptosis, necrosis and NETosis. Its rapidly increased accumulation in blood during tumor development is caused by an excessive DNA release by apoptotic cells and necrotic cells.
FOCAL keystroke programming The alphanumeric "revolution" FOCAL_keystroke_programming > The alphanumeric "revolution" Encoding functions to the corresponding numeric codes, and vice versa, was left to the user, having to look up the function–code combinations in a reference guide. The busy programmer quickly learned most of the codes, but having to learn the codes intimidated the beginners. In addition to this, the user had to mentally keep function codes separate from numeric constants in the program listing.
Flight control modes (electronic) Flight control laws (Airbus) Flight_control_modes > Flight control laws (Airbus) In normal flight, the computers act to prevent excessive forces in pitch and roll.The aircraft is controlled by three primary control computers (captain's, first officer's, and standby) and two secondary control computers (captain's and first officer's). In addition there are two flight control data computers (FCDC) that read information from the sensors, such as air data (airspeed, altitude). This is fed along with GPS data, into three redundant processing units known as air data inertial reference units (ADIRUs) that act both as an air data reference and inertial reference.
Nonalcoholic fatty liver disease Summary Non-alcoholic_fatty_liver_disease Those with NASH have a 2.6% increased risk of dying per year.MAFLD is the most common liver disorder worldwide and is present in approximately 25% of the world's population. It is very common in developed nations, such as the United States, and affected about 75 to 100 million Americans in 2017. Over 90% of obese, 60% of diabetic, and up to 20% of normal-weight people develop NAFLD.
Space Time Continuum Mutual time dilation Lorentz_interval > Spacetime in special relativity > Mutual time dilation and the twin paradox > Mutual time dilation The result OB > OC corresponds again to above. The word "measure" is important. In classical physics an observer cannot affect an observed object, but the object's state of motion can affect the observer's observations of the object.
Laplace–Runge–Lenz vector Noether's theorem Fock_symmetry_in_theory_of_hydrogen > Proofs that the Laplace–Runge–Lenz vector is conserved in Kepler problems > Noether's theorem The connection between the rotational symmetry described above and the conservation of the LRL vector can be made quantitative by way of Noether's theorem. This theorem, which is used for finding constants of motion, states that any infinitesimal variation of the generalized coordinates of a physical system that causes the Lagrangian to vary to first order by a total time derivative corresponds to a conserved quantity Γ In particular, the conserved LRL vector component As corresponds to the variation in the coordinates where i equals 1, 2 and 3, with xi and pi being the i-th components of the position and momentum vectors r and p, respectively; as usual, δis represents the Kronecker delta. The resulting first-order change in the Lagrangian is Substitution into the general formula for the conserved quantity Γ yields the conserved component As of the LRL vector,
Stem cell biology Adult Mother_cell > Adult Adult stem cells, also called somatic (from Greek σωματικóς, "of the body") stem cells, are stem cells which maintain and repair the tissue in which they are found. They can be found in children, as well as adults.There are three known accessible sources of autologous adult stem cells in humans: Bone marrow, which requires extraction by harvesting, usually from pelvic bones via surgery. Adipose tissue (fat cells), which requires extraction by liposuction. Blood, which requires extraction through apheresis, wherein blood is drawn from the donor (similar to a blood donation), and passed through a machine that extracts the stem cells and returns other portions of the blood to the donor.Stem cells can also be taken from umbilical cord blood just after birth.
Magnetic motor Universal AC/DC motor Electrical_motor > Self-commutated motor > Universal AC/DC motor By contrast, maintenance is higher and lifetimes are shortened. Such motors are used in devices that are not heavily used, and have high starting-torque demands. Multiple taps on the field coil provide (imprecise) stepped speed control.
Fine-grained parallelism Coarse-grained parallelism Granularity_(parallel_computing) > Types of parallelism > Coarse-grained parallelism In coarse-grained parallelism, a program is split into large tasks. Due to this, a large amount of computation takes place in processors. This might result in load imbalance, wherein certain tasks process the bulk of the data while others might be idle.
Triatoma virus Replication and transcription Triatoma_virus > Replication cycle > Replication and transcription This circularizes the RNA and allows RNA polymerase to generate negative-sense RNA from the 3’ end while also being able to generate positive-sense RNA from the 5’ end. Translation of the genome is regulated by the binding of 3CD initially to the 5’ UTR. This removes ribosomes from the RNA and makes it solely a replication template. RNA viruses must have a regulatory mechanism that controls whether the genome is transcribed or translated so that it not only produces new viral capsids but also genetic material to fill those capsids.
Cyclical vomiting syndrome Signs and symptoms Cyclic_vomiting_syndrome > Signs and symptoms For other affected people, there is not a pattern in time that can be recognized. Some with the condition have a warning of an episodic attack; they may experience a prodrome, some documented prodromal symptoms include: unusually intense nausea and pallor, excess salivation, sweating, flushing, rapid/irregular heartbeat, diarrhea, anxiety/panic, food aversion, restlessness/insomnia, irritability, depersonalization, fatigue/listlessness, intense feelings of being hot or chilled, intense thirst, shivering/shaking, retching, tachypnea, abdominal pain/cramping, limb paresthesias, hyperesthesia, photophobia, phonophobia, headache, and dyspnea, heightened sensitivity, especially to light, though sensitivity to smell, sound, pressure, and temperature, as well as oncoming muscle pain and fatigue, are also reported by some patients. Many experiences a full panic attack when nausea begins and continue to panic once the vomiting has begun.
Boyer–Moore string-search algorithm Summary Boyer–Moore_string-search_algorithm In computer science, the Boyer–Moore string-search algorithm is an efficient string-searching algorithm that is the standard benchmark for practical string-search literature. It was developed by Robert S. Boyer and J Strother Moore in 1977. The original paper contained static tables for computing the pattern shifts without an explanation of how to produce them.
Solving the heat equation using Fourier series Further applications Solving_the_heat_equation_using_Fourier_series > Applications > Further applications Diffusion problems dealing with Dirichlet, Neumann and Robin boundary conditions have closed form analytic solutions (Thambynayagam 2011). The heat equation is also widely used in image analysis (Perona & Malik 1990) and in machine-learning as the driving theory behind scale-space or graph Laplacian methods.
Glossary of operating systems terms L Glossary_of_operating_systems_terms > L lock: In computer science, a lock or mutex (from mutual exclusion) is a synchronization mechanism for enforcing limits on access to a resource in an environment where there are many threads of execution. A lock is designed to enforce a mutual exclusion concurrency control policy.
Accessory cuneate nucleus Summary Accessory_cuneate_nucleus The accessory cuneate nucleus is located lateral to the cuneate nucleus in the medulla oblongata at the level of the sensory decussation (the crossing fibers of the posterior column/medial lemniscus tract). It receives sensory input about position and movement (proprioception) from the upper limb by way of cervical spinal nerves and transmits that information to the cerebellum.These fibers are called cuneocerebellar (cuneate nucleus → cerebellum) fibers. In this function, the accessory cuneate nucleus is the upper extremity equivalent of Clarke's column, also called the nucleus thoracicus, which is the source of spinocerebellar connections for proprioception from the lower limb.
Pure apocrine carcinoma of the breast Immunohistochemistry Pure_apocrine_carcinoma_of_the_breast > Pathology > Immunohistochemistry HER2/neu is in the epidermal growth factor receptor family. Another member of this family, epidermal growth factor receptor (also termed Her1) is sometimes (e.g. 6% of cases) overexpressed in PACB, particularly in cases that are HER2/neu-negative.All PACB cases have tumor cells which express the alpha-methylacyl-CoA racemase protein and nearly all of these cases have tumor cells which express the GATA3 protein. The identification of these two proteins in tumor cells has helped support the diagnosis of PACB.
Quantitative social research Ethics Quantitative_social_research > Ethics The ethics of social research are shared with those of medical research. In the United States, these are formalized by the Belmont report as:
Power Balance Criticisms Power_Balance > Criticisms Many experts are of the opinion that the Power Balance bracelet is nothing more than a placebo. Victor Thompson, a sports psychologist based in London, said: "I'm not aware of any research that supports the technology behind these bands." Greg Whyte, professor of applied sport and exercise science at Liverpool John Moores University, observed that "for generations there have been devices that claim to mediate the body's flow of energy. In most instances, the 'proof' is based on anecdotal evidence.
Back tracking Description of the method Back_tracking > Description of the method The backtracking algorithm enumerates a set of partial candidates that, in principle, could be completed in various ways to give all the possible solutions to the given problem. The completion is done incrementally, by a sequence of candidate extension steps. Conceptually, the partial candidates are represented as the nodes of a tree structure, the potential search tree.
DNase I hypersensitive site Regulatory DNA tools DNase_I_hypersensitive_site > Regulatory DNA tools Thus, it was able to create a map of candidate enhancers controlling specific genes.The data obtained were validated with the chromosome conformation capture carbon copy (5C) technique. This technique is based in the physical association that exists between the promoter and the enhancers, determining the regions of chromatin that enter in contact in the promoter/enhancer connections. It was confirmed that the majority of promoters were related with more than one enhancer, which indicates the existence of a complicated network of regulation for the immense majority of genes.

Subsets and Splits

No community queries yet

The top public SQL queries from the community will appear here once available.