Split (1)

train · 253k rows

page_content stringlengths 51 3.15k
Erdos–Renyi model Caveats Erdős–Rényi_model > Caveats Both of the two major assumptions of the G(n, p) model (that edges are independent and that each edge is equally likely) may be inappropriate for modeling certain real-life phenomena. Erdős–Rényi graphs have low clustering, unlike many social networks. Some modeling alternatives include Barabási–Albert model and Watts and Strogatz model. These alternative models are not percolation processes, but instead represent a growth and rewiring model, respectively.
International Virtual Observatory Alliance VOTable International_Virtual_Observatory_Alliance > Working Groups > VOTable The VOTable Working Group is in charge of the VOTable format, which is an XML standard for the interchange of data represented as a set of tables. In this context, a table is an unordered set of rows, each of a uniform format, as specified in the table metadata. Each row in a table is a sequence of table cells, and each of these contains either a primitive data type, or an array of such primitives. VOTable is derived from the Astrores format, itself modelled on the FITS Table format; VOTable was designed to be closer to the FITS Binary Table format.
Cayley–Hamilton theorem Summary Hamilton-Cayley_theorem One can create an analogous polynomial p A ( A ) {\displaystyle p_{A}(A)} in the matrix A instead of the scalar variable λ, defined as p A ( A ) = A n + c n − 1 A n − 1 + ⋯ + c 1 A + c 0 I n . {\displaystyle p_{A}(A)=A^{n}+c_{n-1}A^{n-1}+\cdots +c_{1}A+c_{0}I_{n}~.} The Cayley–Hamilton theorem states that this polynomial expression is equal to the zero matrix, which is to say that p A ( A ) = 0 {\displaystyle p_{A}(A)=\mathbf {0} } .
Psychiatric epidemiology Assessment of disorders Psychiatric_epidemiology > Assessment of disorders Many different instruments are used to assess mental disorders in epidemiological studies depending on the age of the participants, available recourses and other considerations. Studies featuring adolescents and adults often use structured interviewing, a technique in which a series of questions is administered by interviewers to determine whether an individual is disordered or nondisordered. Alternatively, questionnaire are used, which can be administered more easily. In epidemiological studies featuring children, psychopathology is often assessed using parent report, however, multi-informant approaches, e.g. the simultaneous use of parent, teachers and self-report, is popular as well.
History of general-purpose CPUs VLIW and EPIC History_of_general-purpose_CPUs > 1990 to today: Looking forward > VLIW and EPIC In January 2000, Transmeta Corporation took the novel step of placing a compiler in the central processing unit, and making the compiler translate from a reference byte code (in their case, x86 instructions) to an internal VLIW instruction set. This method combines the hardware simplicity, low power and speed of VLIW RISC with the compact main memory system and software reverse-compatibility provided by popular CISC. Intel's Itanium chip is based on what they call an explicitly parallel instruction computing (EPIC) design.
Causes of Parkinson's disease Environmental factors Causes_of_Parkinson's_disease > Environmental factors Exposure to pesticides, metals, solvents, and other toxicants has been studied as a factor in the development of Parkinson's disease. No definitive causal relationship has yet been established. Recent studies also reveal that individuals that sustain mild head injuries (concussions) also have an increased risk of acquiring the disease. As discussed below, exercise and caffeine consumption are known to help decrease the risks of acquisition.
Hydrogen evolution reaction Summary Hydrogen_evolution_reaction Hydrogen evolution reaction (HER) is a chemical reaction that yields H2. The conversion of protons to H2 requires reducing equivalents and usually a catalyst. In nature, HER is catalyzed by hydrogenase enzymes. Commercial electrolyzers typically employ platinum metal as the catalyst.
Drosophila embryogenesis Life cycle Drosophila_embryogenesis > Life cycle At this time, segments of the embryo become visible, creating a striped arrangement along the anterior-posterior axis. The earliest signs of segmentation appear during this phase with the formation of parasegmental furrows. This is also when the tracheal pits form, the first signs of structures for breathing. Germ band retraction returns the hindgut to the dorsal side of the posterior pole and coincides with overt segmentation. The remaining stages involve the internalization of the nervous system (ectoderm) and the formation of internal organs (mainly mesoderm).
Anchor Modeling Philosophy Anchor_Modeling > Philosophy Anchor modeling was created in order to take advantage of the benefits from a high degree of normalization while avoiding its drawbacks which higher normal forms have with regards to human readability. Advantages such as being able to non-destructively evolve the model, avoid null values, and keep the information free from redundancies are gained. Performance issues due to extra joins are largely avoided thanks to a feature in modern database engines called join elimination or table elimination. In order to handle changes in the information content, anchor modeling emulates aspects of a temporal database in the resulting relational database schema.
Pulse compression Summary Pulse_compression Pulse compression is a signal processing technique commonly used by radar, sonar and echography to either increase the range resolution when pulse length is constrained or increase the signal to noise ratio when the peak power and the bandwidth (or equivalently range resolution) of the transmitted signal are constrained. This is achieved by modulating the transmitted pulse and then correlating the received signal with the transmitted pulse.
DNA construct Applications Artificial_plasmids > Applications DNA constructs can be used to produce proteins, including both naturally occurring proteins and engineered mutant proteins. These proteins can be used to make therapeutic products, such as pharmaceuticals and antibodies. DNA constructs can also change the expression levels of other genes by expressing regulatory sequences such as promoters and inhibitors. Additionally, DNA constructs can be used for research such as creating genomic libraries, sequencing cloned DNA, and studying RNA and protein expression.
Vertical microcode Comparison to VLIW and RISC Microcode > Comparison to VLIW and RISC Analysis shows complex instructions are rarely used, hence the machine resources devoted to them are largely wasted. The machine resources devoted to rarely used complex instructions are better used for expediting performance of simpler, commonly used instructions. Complex microcoded instructions may require many clock cycles that vary, and are difficult to pipeline for increased performance.There are counterpoints as well: The complex instructions in heavily microcoded implementations may not take much extra machine resources, except for microcode space.
Werner Heisenberg Summary Werner_Heisenberg Werner Karl Heisenberg (pronounced ; 5 December 1901 – 1 February 1976) was a German theoretical physicist and one of the main pioneers of the theory of quantum mechanics. He published his work in 1925 in a major breakthrough paper. In the subsequent series of papers with Max Born and Pascual Jordan, during the same year, his matrix formulation of quantum mechanics was substantially elaborated.
Polo-like kinase 1 Localization Polo-like_kinase_1 > Localization During interphase, PLK1 localizes to centrosomes. In early mitosis, it associates with mitotic spindle poles. A recombinant GFP-PLK1 protein localizes to centromere/kinetochore region, suggesting a possible role for chromosome separation.
Liouville's formula Proof of Liouville's formula Liouville's_formula > Proof of Liouville's formula . . , n} by the linearity of the determinant with respect to every row.
Kelvin water dropper Principles of operation Water-dropping_condenser > Principles of operation This energy comes from the gravitational potential energy released when the water falls. The charged falling water drops do work against the opposing electric field of the like-charged containers, which exerts an upward force against them, converting gravitational potential energy into electrical potential energy, plus motional kinetic energy. The kinetic energy is wasted as heat when the water drops land in the buckets, so when considered as an electric power generator the Kelvin machine is very inefficient. However, the principle of operation is the same as with other forms of hydroelectric power. As always, energy is conserved.
Neurosymbolic AI Summary Neuro-symbolic_AI System 2 handles planning, deduction, and deliberative thinking. In this view, deep learning best handles the first kind of cognition while symbolic reasoning best handles the second kind. Both are needed for a robust, reliable AI that can learn, reason, and interact with humans to accept advice and answer questions. Such dual-process models with explicit references to the two contrasting systems have been worked on since the 1990s, both in AI and in Cognitive Science, by several researchers (e.g.,).
Serine endopeptidase Inhibition Serine_type_carboxypeptidase > Regulation of serine protease activity > Inhibition There are certain inhibitors that resemble the tetrahedral intermediate, and thus fill up the active site, preventing the enzyme from working properly. Trypsin, a powerful digestive enzyme, is generated in the pancreas. Inhibitors prevent self-digestion of the pancreas itself. Serine proteases are paired with serine protease inhibitors, which turn off their activity when they are no longer needed.Serine proteases are inhibited by a diverse group of inhibitors, including synthetic chemical inhibitors for research or therapeutic purposes, and also natural proteinaceous inhibitors.
Inverse discrete Fourier transform Generalized DFT (shifted and non-linear phase) Circular_cross-correlation > Generalized DFT (shifted and non-linear phase) Another interesting choice is a = b = − ( N − 1 ) / 2 {\displaystyle a=b=-(N-1)/2} , which is called the centered DFT (or CDFT). The centered DFT has the useful property that, when N is a multiple of four, all four of its eigenvalues (see above) have equal multiplicities (Rubio and Santhanam, 2005)The term GDFT is also used for the non-linear phase extensions of DFT. Hence, GDFT method provides a generalization for constant amplitude orthogonal block transforms including linear and non-linear phase types. GDFT is a framework to improve time and frequency domain properties of the traditional DFT, e.g. auto/cross-correlations, by the addition of the properly designed phase shaping function (non-linear, in general) to the original linear phase functions (Akansu and Agirman-Tosun, 2010).The discrete Fourier transform can be viewed as a special case of the z-transform, evaluated on the unit circle in the complex plane; more general z-transforms correspond to complex shifts a and b above.
Acidity constant Applications and significance Acid–base_equilibrium > Applications and significance Compared with an aqueous solution, the pH of a buffer solution is relatively insensitive to the addition of a small amount of strong acid or strong base. The buffer capacity of a simple buffer solution is largest when pH = pKa. In acid–base extraction, the efficiency of extraction of a compound into an organic phase, such as an ether, can be optimised by adjusting the pH of the aqueous phase using an appropriate buffer.
Passive sign convention AC circuits Passive_sign_convention > AC circuits However, the average power still obeys the passive sign convention. The average power dissipation over a cycle is P = I V cos ⁡ θ {\displaystyle P=IV\cos {\theta }} , where V {\displaystyle V} is the voltage amplitude, I {\displaystyle I} is the current amplitude and θ {\displaystyle \theta } is the phase angle between them. If the load has resistance, the phase angle θ {\displaystyle \theta } is between +90° and −90°, so the average power is positive.
Object Oriented Programming Criticism Object-oriented_software_engineering > Criticism It claims that everything is an object. Even if it is true it is not very interesting — saying that everything is an object is saying nothing at all. Paul Graham has suggested that OOP's popularity within large companies is due to "large (and frequently changing) groups of mediocre programmers".
Battery torque wrench Summary Battery_torque_wrench The torque output is adjusted by varying the voltage on the motor. The battery torque wrench is used to remove stubborn nuts, or to apply accurate torque. The gearboxes can have multiplication ratios up to 125:1.
Internet tracking Protection through information overflow Internet_privacy > Risks of Internet privacy > Reduction of risks to Internet privacy > Protection through information overflow According to Nicklas Lundblad, another perspective on privacy protection is the assumption that the quickly growing amount of information produced will be beneficial. The reasons for this are that the costs for the surveillance will raise and that there is more noise, noise being understood as anything that interferes the process of a receiver trying to extract private data from a sender. In this noise society, the collective expectation of privacy will increase, but the individual expectation of privacy will decrease. In other words, not everyone can be analyzed in detail, but one individual can be.
Energy landscape Summary Energy_landscape An energy landscape is a mapping of possible states of a system. The concept is frequently used in physics, chemistry, and biochemistry, e.g. to describe all possible conformations of a molecular entity, or the spatial positions of interacting molecules in a system, or parameters and their corresponding energy levels, typically Gibbs free energy. Geometrically, the energy landscape is the graph of the energy function across the configuration space of the system. The term is also used more generally in geometric perspectives to mathematical optimization, when the domain of the loss function is the parameter space of some system.
Stress–strain analysis Fundamental problem Stress–strain_analysis > Scope > Fundamental problem The fundamental problem in stress analysis is to determine the distribution of internal stresses throughout the system, given the external forces that are acting on it. In principle, that means determining, implicitly or explicitly, the Cauchy stress tensor at every point.The external forces may be body forces (such as gravity or magnetic attraction), that act throughout the volume of a material; or concentrated loads (such as friction between an axle and a bearing, or the weight of a train wheel on a rail), that are imagined to act over a two-dimensional area, or along a line, or at single point. The same net external force will have a different effect on the local stress depending on whether it is concentrated or spread out.
Outline of databases Types of databases Outline_of_databases > Types of databases Government database – collects personal information for various reasons (mass surveillance, Schengen Information System in the European Union, social security, statistics, etc.). Graph database – uses graph structures with nodes, edges, and properties to represent and store data. Knowledge base – special kind of database for knowledge management.
Henry J. Kelley Summary Henry_J._Kelley In 1963, he left Grumman (as Assistant Chief of the Research Department) and founded Analytical Mechanics Associates with two partners. In 1978, he became a professor in the Aerospace and Ocean Engineering Department at the Virginia Polytechnic Institute.His paper on "Gradient Theory of Optimal Flight Paths" (1960) is considered a major contribution to the field. In the context of control theory, Kelley derived basics of backpropagation, now widely used for machine learning and artificial neural networks.
Ring signatures Applications and modifications Ring_signatures > Applications and modifications Namely, t parties (i1, i2, ..., it) can compute a (t, n)-ring signature, σ, on a message, m, on input (m, Si1, Si2, ..., Sit, P1, ..., Pn). Linkable ring signatures The property of linkability allows one to determine whether any two signatures have been produced by the same member (under the same private key). The identity of the signer is nevertheless preserved.
Graph grammar Summary Graph_grammar In computer science, graph transformation, or graph rewriting, concerns the technique of creating a new graph out of an original graph algorithmically. It has numerous applications, ranging from software engineering (software construction and also software verification) to layout algorithms and picture generation. Graph transformations can be used as a computation abstraction.
Youth Without Youth (film) Critical response Youth_Without_Youth_(film) > Reception > Critical response You know it's pretentious when the ads print the logo backward and upside down. Not one word of this bilge makes one lick of sense, and it is two hours and six minutes long. The only way to survive Youth Without Youth is dead drunk."
Marine Life Marine bacteria Basal_animal > Microorganisms > Marine bacteria Bacteria constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a number of shapes, ranging from spheres to rods and spirals. Bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, acidic hot springs, radioactive waste, and the deep portions of Earth's crust.
AE index Spacecraft electronics AE_index > Effects > Spacecraft electronics In most cases, the radiation causes an erroneous signal or changes one bit in memory of a spacecraft's electronics (single event upsets). In a few cases, the radiation destroys a section of the electronics (single-event latchup). Spacecraft charging is the accumulation of an electrostatic charge on a nonconducting material on the spacecraft's surface by low-energy particles.
Enzyme cofactor Summary Enzyme_cofactor Many contain the nucleotide adenosine monophosphate (AMP) as part of their structures, such as ATP, coenzyme A, FAD, and NAD+. This common structure may reflect a common evolutionary origin as part of ribozymes in an ancient RNA world. It has been suggested that the AMP part of the molecule can be considered to be a kind of "handle" by which the enzyme can "grasp" the coenzyme to switch it between different catalytic centers.
Social immunity Role in the evolution of group living Social_immunity > Evolution > Role in the evolution of group living The transition from solitary living to group living (identified by John Maynard Smith as one of the seven major transitions in evolutionary history) brought with it many fitness benefits (increased anti-predator vigilance, foraging benefits etc.) and the opportunity to exploit a vast array of new ecological niches, but group living also has its pitfalls. Numerous studies have demonstrated an increase in contact-transmitted parasite load with group size increase, and thus research has been done on the role of social immunity in the evolution of early group living. Empirical evidence already exists, from both interspecific and intraspecific comparative studies, that an increase in population density drives an increase in personal immune effort (density-dependent prophylaxis). However, there is also good evidence that the evolution of social immunity leads to a trade-off between effort into personal immune responses vs. effort in social immune responses - physiological and genomic studies have shown that social conditions can lead to a reduction in personal immune effort.
Amylmetacresol Mechanism of action Amylmetacresol > Pharmacology > Mechanism of action Amylmetacresol is an antibacterial and antiviral substance. It also blocks sodium channels in a manner similar to local anaesthetics. It has a Rideal-Walker coefficient of 250.
Adrenergic neuron blockers Selective beta 1 blockers Adrenergic_neuron_blockers > Adverse Effects > Selectivity > Selective beta 1 blockers Selective beta 1 blockers have been shown to have an array of cardiac common side effects, comprising bradycardia, reduced exercise tolerance, hypotension, atrioventricular block, and heart failure. Regarding non-cardiac side effects, they can cause nausea, headache, fatigue, dry mouth, and dry eyes. In rare cases, confusion, memory loss, and sexual dysfunction are reported. Additionally, beta 1 blockers can mask hypoglycaemia-induced tachycardia in diabetic patients, potentially leading to hypoglycaemic unawareness and subsequent complications if hypoglycaemia is not treated timely. Beta 1 blockers can also mask catecholamine-triggered neurogenic hypoglycaemic symptoms like tremors and palpitations. Since prolonged hypoglycaemia can cause acute brain damage, it is crucial to monitor and treat this condition promptly.
Bernoulli Numbers A combinatorial view: alternating permutations Generalized_Bernoulli_number > A combinatorial view: alternating permutations Around 1880, three years after the publication of Seidel's algorithm, Désiré André proved a now classic result of combinatorial analysis. Looking at the first terms of the Taylor expansion of the trigonometric functions tan x and sec x André made a startling discovery. tan ⁡ x = x + 2 x 3 3 ! + 16 x 5 5 !
Pythagorean equation Non-Euclidean geometry Pythagoras's_theorem > Generalizations > Non-Euclidean geometry The Pythagorean theorem is derived from the axioms of Euclidean geometry, and in fact, were the Pythagorean theorem to fail for some right triangle, then the plane in which this triangle is contained cannot be Euclidean. More precisely, the Pythagorean theorem implies, and is implied by, Euclid's Parallel (Fifth) Postulate. Thus, right triangles in a non-Euclidean geometry do not satisfy the Pythagorean theorem.
Powder diffractometer Crystallinity Powder_diffractometer > Uses > Crystallinity In contrast to a crystalline pattern consisting of a series of sharp peaks, amorphous materials (liquids, glasses etc.) produce a broad background signal. Many polymers show semicrystalline behavior, i.e. part of the material forms an ordered crystallite by folding of the molecule. A single polymer molecule may well be folded into two different, adjacent crystallites and thus form a tie between the two. The tie part is prevented from crystallizing.
Complex Event Processing Summary Complex_Event_Processing Event processing is a method of tracking and analyzing (processing) streams of information (data) about things that happen (events), and deriving a conclusion from them. Complex event processing (CEP) consists of a set of concepts and techniques developed in the early 1990s for processing real-time events and extracting information from event streams as they arrive. The goal of complex event processing is to identify meaningful events (such as opportunities or threats) in real-time situations and respond to them as quickly as possible. These events may be happening across the various layers of an organization as sales leads, orders or customer service calls.
Sp2 bond Summary Hybridised_orbital In chemistry, orbital hybridisation (or hybridization) is the concept of mixing atomic orbitals to form new hybrid orbitals (with different energies, shapes, etc., than the component atomic orbitals) suitable for the pairing of electrons to form chemical bonds in valence bond theory. For example, in a carbon atom which forms four single bonds the valence-shell s orbital combines with three valence-shell p orbitals to form four equivalent sp3 mixtures in a tetrahedral arrangement around the carbon to bond to four different atoms. Hybrid orbitals are useful in the explanation of molecular geometry and atomic bonding properties and are symmetrically disposed in space. Usually hybrid orbitals are formed by mixing atomic orbitals of comparable energies.
Doppler beaming Summary Relativistic_beaming Relativistic beaming (also known as Doppler beaming, Doppler boosting, or the headlight effect) is the process by which relativistic effects modify the apparent luminosity of emitting matter that is moving at speeds close to the speed of light. In an astronomical context, relativistic beaming commonly occurs in two oppositely-directed relativistic jets of plasma that originate from a central compact object that is accreting matter. Accreting compact objects and relativistic jets are invoked to explain x-ray binaries, gamma-ray bursts, and, on a much larger scale, active galactic nuclei (quasars are also associated with an accreting compact object, but are thought to be merely a particular variety of active galactic nuclei, or AGNs).
Discontinuities of monotone functions Jump functions Discontinuities_of_monotone_functions > Jump functions Examples. Let x1 < x2 < x3 < ⋅⋅⋅ be a countable subset of the compact interval and let μ1, μ2, μ3, ... be a positive sequence with finite sum. Set f ( x ) = ∑ n = 1 ∞ μ n χ ( x ) {\displaystyle f(x)=\sum _{n=1}^{\infty }\mu _{n}\chi _{}(x)} where χA denotes the characteristic function of a compact interval A. Then f is a non-decreasing function on , which is continuous except for jump discontinuities at xn for n ≥ 1. In the case of finitely many jump discontinuities, f is a step function.
Kenneth A. Loparo Summary Kenneth_A._Loparo Kenneth A. Loparo is Nord Professor of Engineering and Chair of Department of Electrical Engineering and Computer Science at the Case Western Reserve University, OH, USA, where has been affiliated with since 1979. He was an assistant professor in the Mechanical Engineering Department at Cleveland State University from 1977 to 1979. Prof. Loparo's research interests include stability and control of nonlinear and stochastic systems with applications to large-scale electricity systems including generation and transmission and distribution; nonlinear filtering with applications to monitoring, fault detection, diagnosis, prognosis and reconfigurable control; information theory aspects of stochastic and quantized systems with applications to adaptive and dual control and the design of distributed autonomous control systems; the development of advanced signal processing and data analytics for monitoring and tracking of physiological behavior in health and disease.
Electron Atomic theory Mass_of_electron > History > Atomic theory In turn, he divided the shells into a number of cells each of which contained one pair of electrons. With this model Langmuir was able to qualitatively explain the chemical properties of all elements in the periodic table, which were known to largely repeat themselves according to the periodic law.In 1924, Austrian physicist Wolfgang Pauli observed that the shell-like structure of the atom could be explained by a set of four parameters that defined every quantum energy state, as long as each state was occupied by no more than a single electron. This prohibition against more than one electron occupying the same quantum energy state became known as the Pauli exclusion principle.
Communications management The communication process Communications_management > The communication process The feedback occurs when a receiver decoded the transmitted messaged (converts the message), then encoded a message and sends it back to the source. This also shows an interactive communication process (lumenlearning.com) where the receiver can send feedback to the sender to indicate that the message has been delivered and how it has been interpreted. Interactive communication means that there is a back-and-forth exchange of message and that can assure the source that the message has been received and interpreted correctly.
Ozone shield Summary Ozone_layer The ozone layer or ozone shield is a region of Earth's stratosphere that absorbs most of the Sun's ultraviolet radiation. It contains a high concentration of ozone (O3) in relation to other parts of the atmosphere, although still small in relation to other gases in the stratosphere. The ozone layer contains less than 10 parts per million of ozone, while the average ozone concentration in Earth's atmosphere as a whole is about 0.3 parts per million. The ozone layer is mainly found in the lower portion of the stratosphere, from approximately 15 to 35 kilometers (9 to 22 mi) above Earth, although its thickness varies seasonally and geographically.The ozone layer was discovered in 1913 by French physicists Charles Fabry and Henri Buisson.
System theory Ecology General_Systems_Theory > Applications > Biology > Ecology Systems ecology is an interdisciplinary field of ecology that takes a holistic approach to the study of ecological systems, especially ecosystems; it can be seen as an application of general systems theory to ecology. Central to the systems ecology approach is the idea that an ecosystem is a complex system exhibiting emergent properties. Systems ecology focuses on interactions and transactions within and between biological and ecological systems, and is especially concerned with the way the functioning of ecosystems can be influenced by human interventions. It uses and extends concepts from thermodynamics and develops other macroscopic descriptions of complex systems.
Insertion Sort Best, worst, and average cases Binary_insertion_sort > Best, worst, and average cases The best case input is an array that is already sorted. In this case insertion sort has a linear running time (i.e., O(n)). During each iteration, the first remaining element of the input is only compared with the right-most element of the sorted subsection of the array. The simplest worst case input is an array sorted in reverse order.
Human body Anatomy Human_Physiology > Anatomy Nerves connect the spinal cord and brain to the rest of the body. All major bones, muscles, and nerves in the body are named, with the exception of anatomical variations such as sesamoid bones and accessory muscles. Blood vessels carry blood throughout the body, which moves because of the beating of the heart.
Rotational-vibrational spectroscopy Asymmetric top molecules Rotational-vibrational_spectroscopy > Asymmetric top molecules The bands at shorter wavelength are overtones and combination bands, all of which show rotational fine structure. Medium resolution spectra of the bands around 1600 cm−1 and 3700 cm−1 are shown in Banwell and McCash, p91. Ro-vibrational bands of asymmetric top molecules are classed as A-, B- or C- type for transitions in which the dipole moment change is along the axis of smallest moment of inertia to the highest.
Hashcash Advantages and disadvantages Hashcash > Advantages and disadvantages Most of these issues may be addressed. E.g., botnets may expire faster because users notice the high CPU load and take counter-measures, and mailing list servers can be registered in white lists on the subscribers' hosts and thus be relieved from the hashcash challenges. Another projected problem is that computers continue to get faster according to Moore's law.
Generic top-level domain Geographic gTLD Generic_top-level_domain > Terminology > Geographic gTLD A geographic TLD (or GeoTLD) is a generic top-level domain using the name of or invoking an association with a geographical, geopolitical, ethnic, linguistic or cultural community. As of 2009, only two GeoTLDs existed: the sponsored domains .cat, for the Catalan language and culture and .asia; as of 2014 there were many more, including .kiwi, .paris, .scot and .gal, but many others are being added regularly.
Models of scientific inquiry Deduction Scientific_explanation > Aspects of scientific inquiry > Deduction and induction > Deduction To say that a theorem is proven means that it is impossible for the axioms to be true and the theorem to be false. For example, we could do a simple syllogism such as the following: Arches National Park lies within the state of Utah. I am standing in Arches National Park.
Entropy production Homogeneous systems Entropy_production > Homogeneous systems {\displaystyle \mathrm {d} U=T\mathrm {d} S-p\mathrm {d} V+(H_{\text{m}}-TS_{\text{m}})\mathrm {d} n.} Since H m − T S m = G m = μ {\displaystyle H_{\text{m}}-TS_{\text{m}}=G_{\text{m}}=\mu } with Gm the molar Gibbs free energy and μ the molar chemical potential we obtain the well-known result d U = T d S − p d V + μ d n . {\displaystyle \mathrm {d} U=T\mathrm {d} S-p\mathrm {d} V+\mu \mathrm {d} n.}
Curve on a sphere Basic terminology Surface_area_of_a_sphere > Basic terminology The great circle equidistant to each is then the equator. Great circles through the poles are called lines of longitude or meridians. A line connecting the two poles may be called the axis of rotation.
Lens adapter Summary Lens_adapter In photography and videography, a lens adapter is a device that enables the use of camera and lens combinations from otherwise incompatible systems. The most simple lens adapter designs, passive lens adapters provide a secure physical connection between the camera and the lens. Some passive adapters may include a mechanism for manual iris control. So called, active lens adapters will include electronic connections, enabling communication between the lens and the camera.Some lens adapters include a special optical element called a telecompressor, focal reducer, or more recently a "speed booster", a genericised trademark that refers to the Metabones Speed Booster line of lens adapters.
Scientific management In the 1900s Scientific_management > Variations of scientific management after Taylorism > In the 1900s Taylorism was one of the first attempts to systematically treat management and process improvement as a scientific problem, and Taylor is considered a founder of modern industrial engineering. Taylorism may have been the first "bottom-up" method and found a lineage of successors that have many elements in common. Later methods took a broader approach, measuring not only productivity but quality. With the advancement of statistical methods, quality assurance and quality control began in the 1920s and 1930s.
Dini's theorem Summary Dini's_theorem In the mathematical field of analysis, Dini's theorem says that if a monotone sequence of continuous functions converges pointwise on a compact space and if the limit function is also continuous, then the convergence is uniform.
Complex functions Major results Complex-valued_function > Major results Functions that have only poles but no essential singularities are called meromorphic. Laurent series are the complex-valued equivalent to Taylor series, but can be used to study the behavior of functions near singularities through infinite sums of more well understood functions, such as polynomials.
Ozone destruction Observations on ozone layer depletion Ozone_hole > Observations on ozone layer depletion Marked decreases in column ozone in the Antarctic spring and early summer compared to the early 1970s and before have been observed using instruments such as the Total Ozone Mapping Spectrometer (TOMS).Reductions of up to 70 percent in the ozone column observed in the austral (southern hemispheric) spring over Antarctica and first reported in 1985 (Farman et al.) are continuing. Antarctic total column ozone in September and October have continued to be 40–50 percent lower than pre-ozone-hole values since the 1990s. A gradual trend toward "healing" was reported in 2016.
Microscopic scale Microscopic scale in the laboratory Microscopic_scale > Microscopic scale in the laboratory Whilst use of the microscopic scale has many roles and purposes in the scientific field, there are many biochemical patterns observed microscopically that have contributed significantly to the understanding of how human life relies on microscopic structures to function and live.
Early transition metal pincer complexes Types of pincer ligands Pincer_ligand > Types of pincer ligands The pincer ligand is most often an anionic, two-electron donor to the metal centre. It consists of a rigid, planar backbone usually consisting of aryl frameworks and has two neutral, two-electron donor groups at the meta-positions. The general formula for pincer ligands is 2,6-(ER2)2C6H3 – abbreviated ECE – where E is the two-electron donor and C is the ipso-carbon of the aromatic backbone (e.g. PCP – two phosphine donors). Due to the firm tridentate coordination mode, it allows the metal complexes to exhibit high thermal stability as well as air-stability.
RNA vaccine mRNA RNA_vaccines > mRNA The mRNA nucleotides can be modified to both decrease innate immune activation and increase the mRNA's half-life in the host cell. The nucleic acid sequence and codon usage impacts protein translation. Enriching the sequence with guanine-cytosine content improves mRNA stability and half-life and, in turn, protein production. Replacing rare codons with synonymous codons frequently used by the host cell also enhances protein production.
Seaweed fertilizer Ecosystem services Seaweed_fertilizer > Aquaculture > Ecosystem services Seaweed mariculture for purposes including fertilizer production, has the potential to improve environmental conditions in coastal habitats, especially with regards to toxic algal blooms, as mariculture seaweeds uptake excess nutrients that have resulted from runoff, thereby inhibiting the growth of toxic algal blooms that harm local ecosystems. Seaweed fertilizers can also be more biodegradable, less toxic, and less hazardous than chemical fertilizers, depending on the type of seaweed fertilizer. Seaweeds are used in aquaculture operations to uptake fish waste as nutrients and improve water quality parameters.
RefDB (chemistry) Features RefDB_(chemistry) > Features All chemical shifts in RefDB have been computationally re-referenced to DSS (a common NMR chemical shift standard). RefDB is a continuously updated resource that uses web-bots to query public databases (BMRB, GenBank, Protein Data Bank) and fetch assignment, sequence and structure data on a weekly basis. It then applies a series of data checking routines (using keywords to remove paramagnetic or denatured proteins) followed by a series of calculations to identify and correct chemical shift referencing errors. RefDB is fully web-enabled database, it stores data in two standard formats (NMR-STAR and Shifty), it performs automated data updating, checking and validation and it provides open access to output data in a fully downloadable flat file format as well as in a hyperlinked browsable table (see Fig. 2).
Embedding (topology) Order theory and domain theory Metric_embedding > Order theory and domain theory In order theory, an embedding of partially ordered sets is a function F {\displaystyle F} between partially ordered sets X {\displaystyle X} and Y {\displaystyle Y} such that ∀ x 1 , x 2 ∈ X: x 1 ≤ x 2 ⟺ F ( x 1 ) ≤ F ( x 2 ) . {\displaystyle \forall x_{1},x_{2}\in X:x_{1}\leq x_{2}\iff F(x_{1})\leq F(x_{2}).} Injectivity of F {\displaystyle F} follows quickly from this definition. In domain theory, an additional requirement is that ∀ y ∈ Y: { x ∣ F ( x ) ≤ y } {\displaystyle \forall y\in Y:\{x\mid F(x)\leq y\}} is directed.
Environmental veganism Research and guidance Environmental_veganism > Research and guidance There is inconsistent evidence for vegan diets providing an effect on metabolic syndrome. There is tentative evidence of an association between vegan diets and a reduced risk of cancer. A vegan diet without caloric restriction may reduce high blood pressure similarly to diets recommended by medical societies and portion-controlled diets. Vegans may be at risk of low bone mineral density.
Sigma-1 receptor Ligands Sigma-1_receptor > Ligands The following ligands have high affinity for the σ1 receptor and possess high binding selectivity over the subtype σ2: Agents exist that have high σ1 affinity but either lack subtype selectivity or have high affinity at other binding sites, thus being more or less dirty/multifunctional, like haloperidol. Furthermore, there is a wide range of agents with an at least moderate σ1 involvement in their binding profile.
Computer file system Summary Linux_file_systems In computing, a file system or filesystem (often abbreviated to fs) is a method and data structure that the operating system uses to control how data is stored and retrieved. Without a file system, data placed in a storage medium would be one large body of data with no way to tell where one piece of data stopped and the next began, or where any piece of data was located when it was time to retrieve it. By separating the data into pieces and giving each piece a name, the data are easily isolated and identified. Taking its name from the way a paper-based data management system is named, each group of data is called a "file".
Coefficient of kinetic friction Static friction Force_of_friction > Dry friction > Static friction Static friction is friction between two or more solid objects that are not moving relative to each other. For example, static friction can prevent an object from sliding down a sloped surface. The coefficient of static friction, typically denoted as μs, is usually higher than the coefficient of kinetic friction.
Coercive power Direct Coercive_power > Bases of power > Informational power > Direct Information presented by the influencing agent directly to the target of change.
Eigenvector slew Summary Eigenvector_slew In aerospace engineering, especially those areas dealing with spacecraft, the eigenvector slew is a method to calculate a steering correction (called a slew) by rotating the spacecraft around one fixed axis, or a gimbal. This corresponds in general to the fastest and most efficient way to reach the desired target orientation as there is only one acceleration phase and one braking phase for the angular rate. If this fixed axis is not a principal axis a time varying torque must be applied to force the spacecraft to rotate as desired, though. Also the gyroscopic effect of momentum wheels must be compensated for. That such a rotation exists corresponds precisely to a main result of the mathematical theory of rotation operators, the (only real) eigenvector of the rotation operator corresponding to the desired re-orientation is this axis. Given the current orientation of the craft, and the desired orientation of the craft in cartesian coordinates, the required axis of rotation and corresponding rotation angle to achieve the new orientation is determined by computing the eigenvector of the rotation operator.
Online identity Communication Online_identity > In different contexts > Online learning > Communication There are pros and cons to each side. In a traditional classroom, students are able to visually connect with a teacher who was standing in the same room. During the class, if questions arise, clarification can be provided immediately.
Beta adrenergic receptor kinase carboxyl-terminus Heart Failure Beta_adrenergic_receptor_kinase_carboxyl-terminus > Heart Failure During heart failure, the heart is not able to pump enough blood to the rest of the body and will begin to undergo processes in order to compensate for its decreased function. These processes will attempt to increase the heart’s output; however, the heart may become overstressed and eventually dysfunctional as a result. The sympathetic nervous system increases norepinephrine release to stimulate β-adrenergic receptors (βARs) located on heart cell (cardiomyocyte) membranes to increase the heart’s rate and force of contraction. If the heart is already stressed or damaged, this will cause the heart to work above its capacity.
Debug code C++ example Debug_code > Examples of debug code > Print debugging > C++ example algorithm run 3 times. algorithm run 4 times. algorithm run 5 times.
Substantia nigra Parkinson's disease Substantia_nigra > Clinical significance > Parkinson's disease Because the SNpr is connected to the posterior thalamus, ventral thalamus and specifically, the motor cortex, and because participants with Parkinson's disease report having a smaller SNprs (Menke, Jbabdi, Miller, Matthews and Zari, 2010), the small volume of this region may be responsible for motor impairments found in Parkinson's disease patients. This small volume may be responsible for weaker and/or less controlled motor movements, which may result in the tremors often experienced by those with Parkinson's.Oxidative stress and oxidative damage in the SNpc are likely key drivers in the etiology of Parkinson’s disease as individuals age. DNA damages caused by oxidative stress can be repaired by processes modulated by alpha-synuclein. Alpha synuclein is expressed in the substantia nigra, but its DNA repair function appears to be compromised in Lewy body inclusion bearing neurons. This loss may trigger cell death.
Impact evaluation Experimental approaches Impact_evaluation > Experimental approaches Random sample surveys, in which the sample for the evaluation is chosen randomly, should not be confused with experimental evaluation designs, which require the random assignment of the treatment. The experimental approach is often held up as the 'gold standard' of evaluation. It is the only evaluation design which can conclusively account for selection bias in demonstrating a causal relationship between intervention and outcomes.
Uncertainty Quantification Frequentist Epistemic_probability > Selective methodologies > Inverse uncertainty > Frequentist In regression analysis and least squares problems, the standard error of parameter estimates is readily available, which can be expanded into a confidence interval.
Incidence geometry Fundamental geometric examples Incidence_geometry > Fundamental geometric examples Some of the basic concepts and terminology arises from geometric examples, particularly projective planes and affine planes.
Finite-state entropy Motivating examples Asymmetric_numeral_systems > Entropy coding > Motivating examples A = multiply by 2; B = multiply by 4, add 2; C = multiply by 4, add 3. Express the number in binary, then remove the first digit 1.Consider a more general source with k letters, with rational probabilities n 1 / N , . .
Animal model of schizophrenia Methylazoxymethanol acetate Animal_model_of_schizophrenia > Developmental models > Methylazoxymethanol acetate Methylazoxymethanol acetate (MAM) is used during gestation to affect aspects of neural development. MAM selectively targets neuroblasts in the central nervous system. As neuroblasts are cells which become neurons, interfering with them using MAM inhibits the areas of the brain which are developing most quickly. The effects of MAM therefore depend on the stage of development at which it is administered, or the gestational age of the subject. In rat studies, administration of MAM at day 17 of gestation (GD17) results in several cognitive and anatomical changes which are common to schizophrenia patients. The thickness of the hippocampus and the thalamus are reduced, the locomotor effects of amphetamines and the spontaneous firing rate of dopominergic neurons in the ventral tegmental area are increased, and defects in working spatial memory are observed.
Protective relay Induction disc overcurrent relay Overvoltage_relay > Types according to construction > Induction disc overcurrent relay "Induction" disk meters work by inducing currents in a disk that is free to rotate; the rotary motion of the disk operates a contact. Induction relays require alternating current; if two or more coils are used, they must be at the same frequency otherwise no net operating force is produced. These electromagnetic relays use the induction principle discovered by Galileo Ferraris in the late 19th century.
Discretization of Navier–Stokes equations Summary Discretization_of_Navier–Stokes_equations Discretization of the Navier–Stokes equations of fluid dynamics is a reformulation of the equations in such a way that they can be applied to computational fluid dynamics. Several methods of discretization can be applied: Finite volume method Finite elements method Finite difference method
Dynamic optimality Knuth's dynamic programming algorithm Dynamic_optimality > Static optimality > Knuth's dynamic programming algorithm Let E i j {\displaystyle E_{ij}} be the weighted path length of the statically optimal search tree for all values between ai and aj, let W i j {\displaystyle W_{ij}} be the total weight of that tree, and let R i j {\displaystyle R_{ij}} be the index of its root. The algorithm can be built using the following formulas: E i , i − 1 = W i , i − 1 = B i − 1 for ⁡ 1 ≤ i ≤ n + 1 W i , j = W i , j − 1 + A j + B j E i , j = min i ≤ r ≤ j ( E i , r − 1 + E r + 1 , j + W i , j ) for ⁡ 1 ≤ i ≤ j ≤ n {\displaystyle {\begin{aligned}E_{i,i-1}=W_{i,i-1}&=B_{i-1}\operatorname {for} 1\leq i\leq n+1\\W_{i,j}&=W_{i,j-1}+A_{j}+B_{j}\\E_{i,j}&=\min _{i\leq r\leq j}(E_{i,r-1}+E_{r+1,j}+W_{i,j})\operatorname {for} 1\leq i\leq j\leq n\end{aligned}}} The naive implementation of this algorithm actually takes O(n3) time, but Knuth's paper includes some additional observations which can be used to produce a modified algorithm taking only O(n2) time. In addition to its dynamic programming algorithm, Knuth proposed two heuristics (or rules) to produce nearly (approximation of) optimal binary search trees.
Learning analytics Ethics and privacy Learning_analytics > Ethics and privacy I-nvolve: Talk to stakeholders and give assurances about the data distribution and use. C-onsent: Seek consent through clear consent questions. A-nonymise: De-identify individuals as much as possible T-echnical aspects: Monitor who has access to data, especially in areas with high staff turn-over.
Long COVID Stigma and discrimination Long_COVID > Society and culture > Stigma and discrimination Many people with long COVID have difficulty accessing appropriate healthcare. The severity of their symptoms may be disbelieved, they may be subject to unsympathetic care, and their symptoms may not be investigated properly or may be falsely attributed to anxiety. People with long COVID may be misdiagnosed with mental disorders. Anxiety and depression questionnaires not designed for people with medical conditions can contribute to this; for example, a questionnaire may assume fatigue is due to depression or that palpitations are due to anxiety, even if explained by another condition like ME/CFS or POTS.
ProgramByDesign Functional programming, computing, and algebra ProgramByDesign > Functional programming, computing, and algebra That's how movies are made. The background needed for such an example is little more than knowledge about making movies, about the algebra of pictures in DrRacket (which is like the one for numbers), and minimal pre-algebra.
Progressive Supranuclear Palsy Differential diagnosis Progressive_Supranuclear_Palsy > Diagnosis > Differential diagnosis PSP is frequently misdiagnosed as Parkinson's disease because they both involve slowed movements and gait difficulty, with PSP being one of a collection of diseases referred to as Parkinson plus syndromes. Both Parkinson's and PSP have an onset in late middle age and involve slowing and rigidity of movement. However, several distinguishing features exist. Tremor is very common with Parkinson's, but rare with PSP.
LR parser Grammar for the example A2 + 1 Shift-reduce_conflict > Overview > Grammar for the example A2 + 1 They only happen as a result of the parser applying some grammar rule. Some nonterminals are defined with two or more rules; these are alternative patterns. Rules can refer back to themselves, which are called recursive.
Social simulation game Examples Social_simulation_game > Examples It has also been dubbed as a "communication game" by the company as had Cubivore, Doshin the Giant and GiFTPiA. Real Lives (2001)—an educational life simulator by Educational Simulations where the player is randomly "born" somewhere in the world and often must deal with third-world difficulties such as disease, malnutrition, and civil war. Singles series (2003–2005) Singles: Flirt Up Your Life (2003) Singles 2: Triple Trouble (2005) Democracy (2005)—a government simulation game that was first developed by Positech Games, with a sequel released in December 2007 and a third game in 2013.
Inflammatory disorder Acute process Inflammation > Types > Acute > Acute process The process of acute inflammation is initiated by resident immune cells already present in the involved tissue, mainly resident macrophages, dendritic cells, histiocytes, Kupffer cells and mast cells. These cells possess surface receptors known as pattern recognition receptors (PRRs), which recognize (i.e., bind) two subclasses of molecules: pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs). PAMPs are compounds that are associated with various pathogens, but which are distinguishable from host molecules. DAMPs are compounds that are associated with host-related injury and cell damage.
Functional calculus Summary Functional_calculus Consider the unilateral shift with the polynomials calculus; the ideal defined above is now trivial. Thus one is interested in functional calculi more general than polynomials. The subject is closely linked to spectral theory, since for a diagonal matrix or multiplication operator, it is rather clear what the definitions should be.
Deployment management Computer science Deployment_management > Industry-specific definitions > Computer science In computer science, a deployment is a realisation of a technical specification or algorithm as a program, software component, or other computer system through computer programming and deployment. Many implementations may exist for a given specification or standard. For example, web browsers contain implementations of World Wide Web Consortium-recommended specifications, and software development tools contain deployment of programming languages. A special case occurs in object-oriented programming, when a concrete class deploys an interface; in this case the concrete class is an deployment of the interface and it includes methods which are deployments of those methods specified by the interface.
Microcontroller unit Programming environments Micro_controller > Programming environments Simulators are available for some microcontrollers. These allow a developer to analyze what the behavior of the microcontroller and their program should be if they were using the actual part. A simulator will show the internal processor state and also that of the outputs, as well as allowing input signals to be generated.
Dini's theorem Formal statement Dini's_theorem > Formal statement If X {\displaystyle X} is a compact topological space, and ( f n ) n ∈ N {\displaystyle (f_{n})_{n\in \mathbb {N} }} is a monotonically increasing sequence (meaning f n ( x ) ≤ f n + 1 ( x ) {\displaystyle f_{n}(x)\leq f_{n+1}(x)} for all n ∈ N {\displaystyle n\in \mathbb {N} } and x ∈ X {\displaystyle x\in X} ) of continuous real-valued functions on X {\displaystyle X} which converges pointwise to a continuous function f: X → R {\displaystyle f\colon X\to \mathbb {R} } , then the convergence is uniform. The same conclusion holds if ( f n ) n ∈ N {\displaystyle (f_{n})_{n\in \mathbb {N} }} is monotonically decreasing instead of increasing. The theorem is named after Ulisse Dini.This is one of the few situations in mathematics where pointwise convergence implies uniform convergence; the key is the greater control implied by the monotonicity. The limit function must be continuous, since a uniform limit of continuous functions is necessarily continuous. The continuity of the limit function cannot be inferred from the other hypothesis (consider x n {\displaystyle x^{n}} in {\displaystyle } .)
Simulated patient Advantages Simulated_patient > Advantages Compression/expansion of time: SPs can provide a longitudinal experience and enable students to follow through patients over time, even in a compressed time frame of examination. One technique employed in SP encounters is the use of information cards.
Laminar phase Examples Laminar_phase > Examples Here, the flow is laminar and the boundary layer is a laminar layer. Prandtl applied the concept of the laminar boundary layer to airfoils in 1904.
Multi-function printer Software development kits Multifunction_printer > Software development kits In addition to specific software packages, many vendors also provide the ability for the user to develop software to communicate with the MFP through a Software development kit. Different vendors have different licensing models, from completely "closed" proprietary systems (often with large costs involved) to open strategies with no direct cost involved. An incomplete list of these technologies is: Nuance OmniPage Canon MEAP (Multifunctional Embedded Application Platform) HP Open Extensibility Platform (OXP) Konica Minolta OpenAPI Lexmark Embedded Solutions Framework (eSF) Ricoh’s Device SDK Samsung XOA - eXtensible Open Architecture Sharp OSA (Open Systems Architecture) Toshiba OPA (Open Platform Architecture) Xerox EIP (Extensible Interface Platform)In general, these technologies fall into one of two technical models - Server based, or MFP internal software. Server based technologies use a method to communicate information to and from the MFP (often SOAP/XML based), running the operating code on a suitably powered computer on the network.

Subsets and Splits

No community queries yet

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