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TNM staging system Versions TNM_staging_system > Versions Went into effect 1998. Frederick G, Page DL, Fleming ID, Fritz AG, Balch CM, Haller DG, Morrow M (2002). AJCC Cancer Staging Manual (6th ed.).
Cardiovascular risk Physical inactivity Cardiovascular_conditions > Risk factors > Physical inactivity Insufficient physical activity (defined as less than 5 x 30 minutes of moderate activity per week, or less than 3 x 20 minutes of vigorous activity per week) is currently the fourth leading risk factor for mortality worldwide. In 2008, 31.3% of adults aged 15 or older (28.2% men and 34.4% women) were insufficiently physically active. The risk of ischemic heart disease and diabetes mellitus is reduced by almost a third in adults who participate in 150 minutes of moderate physical activity each week (or equivalent). In addition, physical activity assists weight loss and improves blood glucose control, blood pressure, lipid profile and insulin sensitivity. These effects may, at least in part, explain its cardiovascular benefits.
Logical axiom Other sciences Logical_axiom > Historical development > Other sciences This is due to the heavy use of mathematical tools to support the physical theories. For instance, the introduction of Newton's laws rarely establishes as a prerequisite neither Euclidean geometry or differential calculus that they imply. It became more apparent when Albert Einstein first introduced special relativity where the invariant quantity is no more the Euclidean length l {\displaystyle l} (defined as l 2 = x 2 + y 2 + z 2 {\displaystyle l^{2}=x^{2}+y^{2}+z^{2}} ) > but the Minkowski spacetime interval s {\displaystyle s} (defined as s 2 = c 2 t 2 − x 2 − y 2 − z 2 {\displaystyle s^{2}=c^{2}t^{2}-x^{2}-y^{2}-z^{2}} ), and then general relativity where flat Minkowskian geometry is replaced with pseudo-Riemannian geometry on curved manifolds.
Gamma Cassiopeiae X-ray emission Gamma_Cassiopeiae > Physical properties > X-ray emission Gamma Cassiopeiae is the prototype of a small group of stellar sources of X-ray radiation that is about 10 times stronger than emitted from other B or Be stars. The character of the X-ray spectrum is Be thermal, possibly emitted from plasmas of temperatures up to least ten million kelvins, and shows very short term and long-term cycles. Historically, it has been held that these X-rays might be excited by matter originating from the star, from a hot wind or a disk around the star, accreting onto the surface of a degenerate companion, such as a white dwarf or neutron star.
Fourier Transform Example Fourier_Transform > Example The result is that when you integrate the real part of the integrand you get a relatively large number (in this case 1/2). On the other hand, when you try to measure a frequency that is not present, as in the case when we look at f ^ ( 5 ) {\displaystyle {\hat {f}}(5)} , you see that both real and imaginary component of this function vary rapidly between positive and negative values, as plotted in the third image. Therefore, in this case, the integrand oscillates fast enough so that the integral is very small and the value for the Fourier transform for that frequency is nearly zero. The general situation may be a bit more complicated than this, but this in spirit is how the Fourier transform measures how much of an individual frequency is present in a function f(t).
Mendeleev's table Classification of elements Periodic_system_of_elements > Classification of elements The term "semimetal" has a different definition in physics than it does in chemistry: bismuth is a semimetal by physical definitions, but chemists generally consider it a metal. A few terms are widely used, but without any very formal definition, such as "heavy metal", which has been given such a wide range of definitions that it has been criticised as "effectively meaningless".The scope of terms varies significantly between authors. For example, according to IUPAC, the noble gases extend to include the whole group, including the very radioactive superheavy element oganesson.
Model Predictive Control Robust MPC Model_Predictive_Control > Robust MPC Robust variants of model predictive control are able to account for set bounded disturbance while still ensuring state constraints are met. Some of the main approaches to robust MPC are given below. Min-max MPC. In this formulation, the optimization is performed with respect to all possible evolutions of the disturbance.
Colon carcinoma Cause Colorectal_cancer > Cause 75–95% of colorectal cancer cases occur in people with little or no genetic risk. Risk factors include older age, male sex, high intake of fat, sugar, alcohol, red meat, processed meats, obesity, smoking, and a lack of physical exercise. Approximately 10% of cases are linked to insufficient activity.
Cancer immunology Relationship to chemotherapy Cancer_immunoediting > Relationship to chemotherapy Anthracyclins produce a beneficial immunogenic environment. The researchers report that when killing cancer cells with this agent uptake and presentation by antigen presenting dendritic cells is encouraged, thus allowing a T-cell response which can shrink tumours. Therefore, activating tumour-killing T-cells is crucial for immunotherapy success.However, advanced cancer patients with immunosuppression have left researchers in a dilemma as to how to activate their T-cells. The way the host dendritic cells react and uptake tumour antigens to present to CD4+ and CD8+ T-cells is the key to success of the treatment.
Peer education Theories Peer_education > Theories A variety of theories are offered regarding the question of how peer education is supposed to achieve positive results.
Linezolid Infections of the central nervous system Linezolid > Medical uses > Other > Infections of the central nervous system In animal studies of meningitis caused by Streptococcus pneumoniae, linezolid was found to penetrate well into cerebrospinal fluid, but its effectiveness was inferior to that of other antibiotics. There does not appear to be enough high-quality evidence to support the routine use of linezolid to treat bacterial meningitis. Nonetheless, it has been used successfully in many cases of central nervous system infection—including meningitis—caused by susceptible bacteria, and has also been suggested as a reasonable choice for this indication when treatment options are limited or when other antibiotics have failed. The guidelines of the Infectious Diseases Society of America recommend linezolid as the first-line drug of choice for VRE meningitis, and as an alternative to vancomycin for MRSA meningitis. Linezolid appears superior to vancomycin in treating community-acquired MRSA infections of the central nervous system, although very few cases of such infections have been published (as of 2009).
Hypothesis test Modern origins and early controversy Hypothesis_Testing > History > Modern origins and early controversy Significance testing did not utilize an alternative hypothesis so there was no concept of a Type II error. The p-value was devised as an informal, but objective, index meant to help a researcher determine (based on other knowledge) whether to modify future experiments or strengthen one's faith in the null hypothesis. Hypothesis testing (and Type I/II errors) was devised by Neyman and Pearson as a more objective alternative to Fisher's p-value, also meant to determine researcher behaviour, but without requiring any inductive inference by the researcher.Neyman & Pearson considered a different problem to Fisher (which they called "hypothesis testing").
Structural Engineering Plates Structural_Engineering > Structural elements > Plates Plates carry bending in two directions. A concrete flat slab is an example of a plate. Plates are understood by using continuum mechanics, but due to the complexity involved they are most often designed using a codified empirical approach, or computer analysis. They can also be designed with yield line theory, where an assumed collapse mechanism is analyzed to give an upper bound on the collapse load. This technique is used in practice but because the method provides an upper-bound (i.e. an unsafe prediction of the collapse load) for poorly conceived collapse mechanisms, great care is needed to ensure that the assumed collapse mechanism is realistic.
Hypothesis Theory Status of Research Hypothesis_Theory > Status of Research Hypothesis theory has fallen out of favor (along with many other rule-based models) in the wake of prototype and exemplar theories, both of which employ a notion of graded similarity rather than crisp set membership.
Mohs surgery Cure rate variation Mohs_surgery > Cure rate > Cure rate variation Two histologic sections can not fully distinguish these two nearly identical structures, and can lead to either "false negative" or "false positive" errors by either calling a section clear of tumor, or calling a section positive for tumor, respectively. : 134, 453 Serial sectioning of the tumor is preferred by other surgeons. : 62, 272 Surgeons who perform serial sectioning through the block of tissue (usually 100 micrometres apart) are assured of the contiguous nature of his tumor and the distance of the tumor from the surgical margin, and are familiarized with the nature of the tumor.
Available energy Applications in natural resource utilization Available_energy > Applications > Applications in natural resource utilization Referencing the inherent qualities of a system in place of a reference state environment is the most direct way that ecologists determine the exergy of a natural resource. Specifically, it is easiest to examine the thermodynamic properties of a system, and the reference substances that are acceptable within the reference environment. This determination allows for the assumption of qualities in a natural state: deviation from these levels may indicate a change in the environment caused by outside sources.
Privacy engineering Core practices Privacy_protection > Core practices As this particular field is still in its infancy and somewhat dominated by the legal aspects, the following list just outlines the primary areas on which privacy engineering is based: Data flow modelling Development of suitable terminologies/ontologies for expressing types, usages, purposes etc. of information Privacy Impact Assessment (PIA) Privacy management and processes Requirements engineering Risk assessment SemanticsDespite the lack of a cohesive development of the above areas, courses already exist for the training of privacy engineering. The International Workshop on Privacy Engineering co-located with IEEE Symposium on Security and Privacy provides a venue to address "the gap between research and practice in systematizing and evaluating approaches to capture and address privacy issues while engineering information systems".A number of approaches to privacy engineering exist. The LINDDUN methodology takes a risk-centric approach to privacy engineering where personal data flows at risk are identified and then secured with privacy controls. Guidance for interpretation of the GDPR has been provided in the GDPR recitals, which have been coded into a decision tool that maps GDPR into software engineering forces with the goal to identify suitable privacy design patterns. One further approach uses eight privacy design strategies - four technical and four administrative strategies - to protect data and to implement data subject rights.
The Selfish Gene Units of selection The_Selfish_Gene > Reception > Units of selection ...The important differences between genes emerge only in their effects. The technical word phenotype is used for the bodily manifestation of a gene, the effect that a gene has on the body...Natural selection favours some genes rather than others not because of the nature of the genes themselves, but because of their consequences—their phenotypic effects...But we shall now see that the phenotypic effects of a gene need to be thought of as all the effects that it has on the world. ...The phenotypic effects of a gene are the tools by which it levers itself into the next generation.
Markov Chains and Mixing Times Topics Markov_Chains_and_Mixing_Times > Topics The book is divided into two parts, the first more introductory and the second more advanced. After three chapters of introductory material on Markov chains, chapter four defines the ways of measuring the distance of a Markov chain to its stationary distribution and the time it takes to reach that distance. Chapter five describes coupling, one of the standard techniques of bounding mixing times. In this technique, one sets up two Markov chains, one starting from the given initial state and the other from the stationary distribution, with transitions that have the correct probabilities within each chain but are not independent from chain-to-chain, in such a way that the two chains become likely to move to the same states as each other.
Lie group–Lie algebra correspondence The Lie algebra of a Lie group Lie_group–Lie_algebra_correspondence > Basics > The Lie algebra of a Lie group Moreover, it is closed under Lie bracket; i.e., {\displaystyle } is left-translation-invariant if X, Y are. Thus, Lie ⁡ ( G ) {\displaystyle \operatorname {Lie} (G)} is a Lie subalgebra of the Lie algebra of all vector fields on G and is called the Lie algebra of G. One can understand this more concretely by identifying the space of left-invariant vector fields with the tangent space at the identity, as follows: Given a left-invariant vector field, one can take its value at the identity, and given a tangent vector at the identity, one can extend it to a left-invariant vector field. This correspondence is one-to-one in both directions, so is bijective. Thus, the Lie algebra can be thought of as the tangent space at the identity and the bracket of X and Y in T e G {\displaystyle T_{e}G} can be computed by extending them to left-invariant vector fields, taking the bracket of the vector fields, and then evaluating the result at the identity. There is also another incarnation of Lie ⁡ ( G ) {\displaystyle \operatorname {Lie} (G)} as the Lie algebra of primitive elements of the Hopf algebra of distributions on G with support at the identity element; for this, see #Related constructions below.
Ionic strength Summary Ionic_strength One of the main characteristics of a solution with dissolved ions is the ionic strength. Ionic strength can be molar (mol/L solution) or molal (mol/kg solvent) and to avoid confusion the units should be stated explicitly. The concept of ionic strength was first introduced by Lewis and Randall in 1921 while describing the activity coefficients of strong electrolytes.
PNP transistor Voltage, current, and charge control N–p–n_transistor > Function > Voltage, current, and charge control The voltage-control model requires an exponential function to be taken into account, but when it is linearized such that the transistor can be modeled as a transconductance, as in the Ebers–Moll model, design for circuits such as differential amplifiers again becomes a mostly linear problem, so the voltage-control view is often preferred. For translinear circuits, in which the exponential I–V curve is key to the operation, the transistors are usually modeled as voltage-controlled current sources whose transconductance is proportional to their collector current. In general, transistor-level circuit analysis is performed using SPICE or a comparable analog-circuit simulator, so mathematical model complexity is usually not of much concern to the designer, but a simplified view of the characteristics allows designs to be created following a logical process.
Agent-based model in biology Stochasticity Agent-based_model_in_biology > Characteristics > Stochasticity Biological systems exhibit behavior that appears to be random. The probability of a particular behavior can be determined for a system as a whole and then be translated into rules for the individual agents.
Global health HIV/AIDS Global_health > Health topics > Infectious diseases > HIV/AIDS Globally, HIV is primarily spread through sexual intercourse. The risk-per-exposure with vaginal sex in low-income countries from female to male is 0.38% and male to female is 0.3%. The infection damages the immune system, leading to acquired immunodeficiency syndrome (AIDS) and eventually, death. Antiretroviral drugs prolong life and delay the onset of AIDS by minimizing the amount of HIV in the body.
Optical physicist Summary Optical_system The most common of these, geometric optics, treats light as a collection of rays that travel in straight lines and bend when they pass through or reflect from surfaces. Physical optics is a more comprehensive model of light, which includes wave effects such as diffraction and interference that cannot be accounted for in geometric optics. Historically, the ray-based model of light was developed first, followed by the wave model of light.
Java Platform, Standard Edition java.nio Java_Platform,_Standard_Edition > General purpose packages > java.nio In J2SE 1.4, the package java.nio (NIO or Non-blocking I/O) was added to support memory-mapped I/O, facilitating I/O operations closer to the underlying hardware with sometimes dramatically better performance. The java.nio package provides support for a number of buffer types. The subpackage java.nio.charset provides support for different character encodings for character data. The subpackage java.nio.channels provides support for channels, which represent connections to entities that are capable of performing I/O operations, such as files and sockets. The java.nio.channels package also provides support for fine-grained locking of files.
Pumping lemma for regular languages Formal statement Pumping_lemma_for_regular_languages > Formal statement Let L {\displaystyle L} be a regular language. Then there exists an integer p ≥ 1 {\displaystyle p\geq 1} depending only on L {\displaystyle L} such that every string w {\displaystyle w} in L {\displaystyle L} of length at least p {\displaystyle p} ( p {\displaystyle p} is called the "pumping length") can be written as w = x y z {\displaystyle w=xyz} (i.e., w {\displaystyle w} can be divided into three substrings), satisfying the following conditions: \| y \| ≥ 1 {\displaystyle \|y\|\geq 1} \| x y \| ≤ p {\displaystyle \|xy\|\leq p} ( ∀ n ≥ 0 ) ( x y n z ∈ L ) {\displaystyle (\forall n\geq 0)(xy^{n}z\in L)} y {\displaystyle y} is the substring that can be pumped (removed or repeated any number of times, and the resulting string is always in L {\displaystyle L} ). (1) means the loop y {\displaystyle y} to be pumped must be of length at least one; (2) means the loop must occur within the first p {\displaystyle p} characters. \| x \| {\displaystyle \|x\|} must be smaller than p {\displaystyle p} (conclusion of (1) and (2)), but apart from that, there is no restriction on x {\displaystyle x} and z {\displaystyle z} .
Verilog Definition of constants Verilog > Definition of constants The definition of constants in Verilog supports the addition of a width parameter. The basic syntax is: ' Examples: 12'h123 – Hexadecimal 123 (using 12 bits) 20'd44 – Decimal 44 (using 20 bits – 0 extension is automatic) 4'b1010 – Binary 1010 (using 4 bits) 6'o77 – Octal 77 (using 6 bits)
Steady flight Force balance and the steady flight equations Level_flight > Force balance and the steady flight equations The forces acting on an aircraft in flight are the weight, aerodynamic force, and thrust. The weight is easiest to express in the Earth frame, where it has magnitude W and is in the +zE direction, towards the center of the Earth. The weight is assumed to be constant over time and constant with altitude. Expressing the aerodynamic force in the wind frame, it has a drag component with magnitude D opposite the velocity vector in the −xw direction, a side force component with magnitude C in the +yw direction, and a lift component with magnitude L in the −zw direction.
Sergey Piletsky Most widely cited books and book chapters Sergey_Piletsky > Most widely cited books and book chapters ), "Computational Approaches in the Design of Synthetic Receptors", Designing Receptors for the Next Generation of Biosensors, Berlin, Heidelberg: Springer Berlin Heidelberg, vol. 12, pp. 131–165, doi:10.1007/5346_2012_22, ISBN 978-3-642-32328-7, retrieved 2022-08-17 Subrahmanyam, Sreenath; Piletsky, Sergey A.
Gabriel Pareyon Articles / Chapters (selection) Gabriel_Pareyon > Articles / Chapters (selection) DOI: 10.46926/musmat.2022v6n1.12-47. “Philosophical Sketches on Category Theory Applied to Music-Mathematical Polar Semiotics”, MusMat - Brazilian Journal of Music and Mathematics, 4(2), dic. 2020; pp.
Septic shock Vasopressors Septic_shock > Treatment > Vasopressors Dopamine may cause rapid heart rate and arrhythmias, and is only recommended in combination with norepinephrine in those with slow heart rate and low risk of arrhythmia. In the initial treatment of low blood pressure in septic shock, the goal of vasopressor treatment is a mean arterial pressure (MAP) of 65 mm Hg. In 2017, the FDA approved angiotensin II injection for intravenous infusion to increase blood pressure in adults with septic or other distributive shock.
Cellular computing Evolutionary computation Cellular_computing > Nature-inspired models of computation > Evolutionary computation At each step, the individuals are evaluated according to the given fitness function (survival of the fittest). The next generation is obtained from selected individuals (parents) by using genetically inspired operators. The choice of parents can be guided by a selection operator which reflects the biological principle of mate selection.
Natural radiation Summary Background_Radiation Background radiation is a measure of the level of ionizing radiation present in the environment at a particular location which is not due to deliberate introduction of radiation sources. Background radiation originates from a variety of sources, both natural and artificial. These include both cosmic radiation and environmental radioactivity from naturally occurring radioactive materials (such as radon and radium), as well as man-made medical X-rays, fallout from nuclear weapons testing and nuclear accidents.
CAD/CAM dentistry Digital impressions CAD/CAM_dentistry > Computer-aided design (CAD) > Digital impressions Contact scanners are more accurate than non-contact scanners but are rarely used anymore because they are slow and their imaging is unnecessarily detailed, ten times what is required for the success of a dental prosthesis.Intra-oral scanners are a form of non-contact scanners that have grown in popularity due to their ability to digitize a patient’s dentition directly in the mouth, avoiding the need for either a physical impression or a plaster study model, as is the case with extraoral scanners. This allows the fabrication of dental prostheses to be a completely digital process from the very first stage.
Bacterial wall The gram-positive cell wall Bacterial_cell_structure > Cell wall > The gram-positive cell wall They have O-acetyl groups on carbon-6 of some muramic acid residues. The matrix substances in the walls of gram-positive bacteria may be polysaccharides or teichoic acids.
Measurement in quantum theory "Observables" as self-adjoint operators Measurement_in_quantum_theory > Mathematical formalism > "Observables" as self-adjoint operators The dimension of the Hilbert space may be infinite, as it is for the space of square-integrable functions on a line, which is used to define the quantum physics of a continuous degree of freedom. Alternatively, the Hilbert space may be finite-dimensional, as occurs for spin degrees of freedom. Many treatments of the theory focus on the finite-dimensional case, as the mathematics involved is somewhat less demanding. Indeed, introductory physics texts on quantum mechanics often gloss over mathematical technicalities that arise for continuous-valued observables and infinite-dimensional Hilbert spaces, such as the distinction between bounded and unbounded operators; questions of convergence (whether the limit of a sequence of Hilbert-space elements also belongs to the Hilbert space), exotic possibilities for sets of eigenvalues, like Cantor sets; and so forth. : 79 These issues can be satisfactorily resolved using spectral theory;: 101 the present article will avoid them whenever possible.
Tokenization (data security) System operations, limitations and evolution Tokenization_(data_security) > System operations, limitations and evolution First generation tokenization systems use a database to map from live data to surrogate substitute tokens and back. This requires the storage, management, and continuous backup for every new transaction added to the token database to avoid data loss. Another problem is ensuring consistency across data centers, requiring continuous synchronization of token databases. Significant consistency, availability and performance trade-offs, per the CAP theorem, are unavoidable with this approach.
Naturally occurring element Classical definitions Chemical_element > History > Evolving definitions > Classical definitions Ancient philosophy posited a set of classical elements to explain observed patterns in nature. These elements originally referred to earth, water, air and fire rather than the chemical elements of modern science. The term 'elements' (stoicheia) was first used by the Greek philosopher Plato in about 360 BCE in his dialogue Timaeus, which includes a discussion of the composition of inorganic and organic bodies and is a speculative treatise on chemistry. Plato believed the elements introduced a century earlier by Empedocles were composed of small polyhedral forms: tetrahedron (fire), octahedron (air), icosahedron (water), and cube (earth).Aristotle, c. 350 BCE, also used the term stoicheia and added a fifth element called aether, which formed the heavens. Aristotle defined an element as: Element – one of those bodies into which other bodies can decompose, and that itself is not capable of being divided into other.
Phagocytic cells Evolutionary origins Phagocytic_cells > Evolutionary origins They are genetically identical to the other amoebae in the slug; their self-sacrifice to protect the other amoebae from bacteria is similar to the self-sacrifice of phagocytes seen in the immune system of higher vertebrates. This ancient immune function in social amoebae suggests an evolutionarily conserved cellular foraging mechanism that might have been adapted to defense functions well before the diversification of amoebae into higher forms. Phagocytes occur throughout the animal kingdom, from marine sponges to insects and lower and higher vertebrates. The ability of amoebae to distinguish between self and non-self is a pivotal one, and is the root of the immune system of many species of amoeba.
Myelodysplastic syndromes Management Myelodysplastic_syndromes > Management However, no comment on the use of hematopoietic growth factors for MDS was made in that document.Agents have been approved by the U.S. Food and Drug Administration (FDA) for the treatment of MDS: 5-azacytidine: 21-month median survival Decitabine: Complete response rate reported as high as 43%. A phase I study has shown efficacy in AML when decitabine is combined with valproic acid.
Network calculus Summary Network_calculus Network calculus is "a set of mathematical results which give insights into man-made systems such as concurrent programs, digital circuits and communication networks." Network calculus gives a theoretical framework for analysing performance guarantees in computer networks. As traffic flows through a network it is subject to constraints imposed by the system components, for example: link capacity traffic shapers (leaky buckets) congestion control background trafficThese constraints can be expressed and analysed with network calculus methods. Constraint curves can be combined using convolution under min-plus algebra.
Branching (linguistics) Tree structures Branching_(linguistics) > Tree structures The following trees illustrate phrases that combine both types of branching: The combination of left- and right-branching is now completely visible in both the constituency- and dependency-based trees. The head appears in a medial position, which means that the phrase combines both types of branching. Note that the (b)-trees also contain a PP phrase that is an instance of pure right-branching.
Cerebellar cortex Comparative anatomy and evolution Granule_cell_layer > Comparative anatomy and evolution There is considerable variation in the size and shape of the cerebellum in different vertebrate species. In amphibians, it is little developed, and in lampreys, and hagfish, the cerebellum is barely distinguishable from the brain-stem. Although the spinocerebellum is present in these groups, the primary structures are small, paired-nuclei corresponding to the vestibulocerebellum.
Foregrounding Origin Foregrounding > Origin The purpose of art is to impart the sensation of things as they are perceived and not as they are known. The technique of art is to make objects "unfamiliar," to make forms difficult, to increase the difficulty and length of perception because the process of perception is an aesthetic end in itself and must be prolonged."
Radial basis function kernel Approximations Radial_basis_function_kernel > Approximations Because support vector machines and other models employing the kernel trick do not scale well to large numbers of training samples or large numbers of features in the input space, several approximations to the RBF kernel (and similar kernels) have been introduced. Typically, these take the form of a function z that maps a single vector to a vector of higher dimensionality, approximating the kernel: ⟨ z ( x ) , z ( x ′ ) ⟩ ≈ ⟨ φ ( x ) , φ ( x ′ ) ⟩ = K ( x , x ′ ) {\displaystyle \langle z(\mathbf {x} ),z(\mathbf {x'} )\rangle \approx \langle \varphi (\mathbf {x} ),\varphi (\mathbf {x'} )\rangle =K(\mathbf {x} ,\mathbf {x'} )} where φ {\displaystyle \textstyle \varphi } is the implicit mapping embedded in the RBF kernel.
Mal regulon Summary Mal_regulon In bacterial genetics, the mal regulon is a regulon - or group of genes under common regulation - associated with the catabolism of maltose and maltodextrins. The system is especially well characterized in the model organism Escherichia coli, where it is classically described as a group of ten genes in multiple operons whose expression is regulated by a single regulatory protein, malT. MalT binds to maltose or maltodextrin and undergoes a conformational change that allows it to bind DNA at sequences near the promoters of genes required for uptake and catabolism of these sugars. The maltose regulation system in E. coli is a classic example of positive regulation.
Homomorphic equivalence Summary Homomorphic_equivalence In the mathematics of graph theory, two graphs, G and H, are called homomorphically equivalent if there exists a graph homomorphism f: G → H {\displaystyle f\colon G\to H} and a graph homomorphism g: H → G {\displaystyle g\colon H\to G} . An example usage of this notion is that any two cores of a graph are homomorphically equivalent. Homomorphic equivalence also comes up in the theory of databases.
Passive safety Crashworthiness Passive_safety > Active and passive safety > Crashworthiness Crashworthy systems and devices prevent or reduce the severity of injuries when a crash is imminent or actually happening. Much research is carried out using anthropomorphic crash test dummies. Seatbelts limit the forward motion of an occupant, stretch to absorb energy, to lengthen the time of the occupant's negative acceleration in a crash, reducing the loading on the occupants' body. They prevent occupants being ejected from the vehicle and ensure that they are in the correct position for the operation of the airbags.
Symmetric group Low degree groups Symmetric_group > Low degree groups Beyond the group A4, S4 has a Klein four-group V as a proper normal subgroup, namely the even transpositions {(1), (1 2)(3 4), (1 3)(2 4), (1 4)(2 3)}, with quotient S3. In Galois theory, this map corresponds to the resolving cubic to a quartic polynomial, which allows the quartic to be solved by radicals, as established by Lodovico Ferrari. The Klein group can be understood in terms of the Lagrange resolvents of the quartic.
Artstein's theorem Summary Artstein's_theorem Artstein's theorem states that a nonlinear dynamical system in the control-affine form x ˙ = f ( x ) + ∑ i = 1 m g i ( x ) u i {\displaystyle {\dot {\mathbf {x} }}=\mathbf {f(x)} +\sum _{i=1}^{m}\mathbf {g} _{i}(\mathbf {x} )u_{i}} has a differentiable control-Lyapunov function if and only if it admits a regular stabilizing feedback u(x), that is a locally Lipschitz function on Rn\{0}.The original 1983 proof by Zvi Artstein proceeds by a nonconstructive argument. In 1989 Eduardo D. Sontag provided a constructive version of this theorem explicitly exhibiting the feedback.
2-hydroxy-dATP diphosphatase Cancer 2-hydroxy-dATP_diphosphatase > Research > Cancer Specifically, another study found that MTH1 inhibition in cancer cells leads to incorporation of 8-oxo-dGTP and other oxidatively damaged nucleotides into the cell's DNA, damaging it and causing cell death. However, cancer cells have also been shown to benefit from use of MTH1. Cells from malignant breast tumors exhibit extreme MTH1 expression compared to other human cells.
Ecological validity (perception) Role of "ecological validity" in a "representative design" Ecological_validity_(perception) > Role of "ecological validity" in a "representative design" . of each variable, has been made representative of a carefully defined set of conditions" (1956, p. 53).
Non-aggression Principle Justifications Non-aggression_Principle > Justifications She stressed that the political principle of non-aggression is not a primary and that it only has validity as a consequence of a more fundamental philosophy. For this reason, many of her conclusions differ from others who hold the NAP as an axiom or arrived at it differently. She proposed that man survives by identifying and using concepts in his rational mind since "no sensations, percepts, urges or instincts can do it; only a mind can".
Enzyme promiscuity Summary Promiscuous_activity Enzyme promiscuity is the ability of an enzyme to catalyse a fortuitous side reaction in addition to its main reaction. Although enzymes are remarkably specific catalysts, they can often perform side reactions in addition to their main, native catalytic activity. These promiscuous activities are usually slow relative to the main activity and are under neutral selection.
History of optics Diffractive optics History_of_optics > Renaissance and Early Modern > Diffractive optics James Gregory (1638–1675) observed the diffraction patterns caused by a bird feather, which was effectively the first diffraction grating. In 1803 Thomas Young did his famous experiment observing interference from two closely spaced slits in his double slit interferometer. Explaining his results by interference of the waves emanating from the two different slits, he deduced that light must propagate as waves. Augustin-Jean Fresnel did more definitive studies and calculations of diffraction, published in 1815 and 1818, and thereby gave great support to the wave theory of light that had been advanced by Christiaan Huygens and reinvigorated by Young, against Newton's particle theory.
Schrödinger's equation Interpretation Schrödinger_Equation > Interpretation The post-measurement wave function generally cannot be known prior to the measurement, but the probabilities for the different possibilities can be calculated using the Born rule. Other, more recent interpretations of quantum mechanics, such as relational quantum mechanics and QBism also give the Schrödinger equation a status of this sort.Schrödinger himself suggested in 1952 that the different terms of a superposition evolving under the Schrödinger equation are "not alternatives but all really happen simultaneously". This has been interpreted as an early version of Everett's many-worlds interpretation.
Cop-win graph Pursuit–evasion Bridged_graph > Definitions > Pursuit–evasion The game ends, and the cop wins, if the cop can end a turn on the same vertex as the robber. The robber wins by indefinitely evading the cop. A cop-win graph is a graph with the property that, when the players choose starting positions and then move in this way, the cop can always force a win. If an undirected graph is not a cop-win graph, it is called a robber-win graph.
Capreomycin Summary Capreomycin Capreomycin is an antibiotic which is given in combination with other antibiotics for the treatment of tuberculosis. Specifically it is a second line treatment used for active drug resistant tuberculosis. It is given by injection into a vein or muscle.Common side effects include kidney problems, hearing problems, poor balance, and pain at the site of injection. Other side effects include paralysis resulting in the inability to breathe.
Mixed layer Oceanic mixed layer formation Mixed_layer > Oceanic mixed layer > Oceanic mixed layer formation If ocean currents vary with depth, waves can interact with them to drive the process known as Langmuir circulation, large eddies that stir down to depths of tens of meters. The second is wind-driven currents, which create layers in which there are velocity shears.
Glossary of computer science D Glossary_of_computer_science > D Beyond the name (the identifier itself) and the kind of entity (function, variable, etc.), declarations typically specify the data type (for variables and constants), or the type signature (for functions); types may also include dimensions, such as for arrays. A declaration is used to announce the existence of the entity to the compiler; this is important in those strongly typed languages that require functions, variables, and constants, and their types, to be specified with a declaration before use, and is used in forward declaration. The term "declaration" is frequently contrasted with the term "definition", but meaning and usage varies significantly between languages.
Atomic, molecular, and optical physics Early quantum model of matter and light Optical_sciences > History > Early quantum model of matter and light : 8 Work by Albert Einstein in 1905 on the photoelectric effect led to the association of a light wave of frequency ν {\displaystyle \nu } with a photon of energy h ν {\displaystyle h\nu } . In 1917 Einstein created an extension to Bohrs model by the introduction of the three processes of stimulated emission, spontaneous emission and absorption (electromagnetic radiation). : 11
Phi-hiding assumption Applications Phi-hiding_assumption > Applications The Phi-hiding assumption has found applications in the construction of a few cryptographic primitives. Some of the constructions include: Computationally Private Information Retrieval with Polylogarithmic Communication (1999) Efficient Private Bidding and Auctions with an Oblivious Third Party (1999) Single-Database Private Information Retrieval with Constant Communication Rate (2005) Password authenticated key exchange using hidden smooth subgroups (2005) == References ==
Pythagoras tree (fractal) Construction Pythagoras_tree_(fractal) > Construction The construction of the Pythagoras tree begins with a square. Upon this square are constructed two squares, each scaled down by a linear factor of √2/2, such that the corners of the squares coincide pairwise. The same procedure is then applied recursively to the two smaller squares, ad infinitum. The illustration below shows the first few iterations in the construction process. This is the simplest symmetric triangle. Alternatively, the sides of the triangle are recursively equal proportions, leading to the sides being proportional to the square root of the inverse golden ratio, and the areas of the squares being in golden ratio proportion.
Chemical Science Modern principles Modern_chemistry > Modern principles The current model of atomic structure is the quantum mechanical model. Traditional chemistry starts with the study of elementary particles, atoms, molecules, substances, metals, crystals and other aggregates of matter. Matter can be studied in solid, liquid, gas and plasma states, in isolation or in combination. The interactions, reactions and transformations that are studied in chemistry are usually the result of interactions between atoms, leading to rearrangements of the chemical bonds which hold atoms together.
Turing Machines Primary literature, reprints, and compilations Turing_Machines > References > Primary literature, reprints, and compilations 42: 230–265. doi:10.1112/plms/s2-42.1.230. S2CID 73712.
Closed loop transfer function Overview Closed-loop_transfer_function > Overview The closed-loop transfer function is measured at the output. The output signal can be calculated from the closed-loop transfer function and the input signal. Signals may be waveforms, images, or other types of data streams. An example of a closed-loop transfer function is shown below: The summing node and the G(s) and H(s) blocks can all be combined into one block, which would have the following transfer function: Y ( s ) X ( s ) = G ( s ) 1 + G ( s ) H ( s ) {\displaystyle {\dfrac {Y(s)}{X(s)}}={\dfrac {G(s)}{1+G(s)H(s)}}} G ( s ) {\displaystyle G(s)} is called feedforward transfer function, H ( s ) {\displaystyle H(s)} is called feedback transfer function, and their product G ( s ) H ( s ) {\displaystyle G(s)H(s)} is called the open-loop transfer function.
Optimal design of experiments Historical Optimal_design_of_experiments > Further reading > Historical Historia Mathematica. 1 (4): 431–439. doi:10.1016/0315-0860(74)90033-0.
Adjustable stabilizer Wing-stabilizer interaction Adjustable_stabilizer > Horizontal stabilizers > Wing-stabilizer interaction The upwash and downwash associated with the generation of lift is the source of aerodynamic interaction between the wing and stabilizer, which translates into a change in the effective angle of attack for each surface. The influence of the wing on a tail is much more significant than the opposite effect and can be modeled using the Prandtl lifting-line theory; however, an accurate estimation of the interaction between multiple surfaces requires computer simulations or wind tunnel tests.
McShane integral Example 2 McShane_integral > Examples > Example 2 Let d: → R {\displaystyle d:\rightarrow \mathbb {R} } the well known Dirichlet's function given by d ( x ) = { 1 , if x is rational, 0 , if x is irrational, {\displaystyle d(x)={\begin{cases}1,&{\text{if }}x{\text{ is rational,}}\\0,&{\text{if }}x{\text{ is irrational,}}\end{cases}}} which one knows to be not Riemann integrable. We will show that d {\displaystyle d} is integrable in the MacShane sense and that its integral is zero. Denoting by { r 1 , r 2 , . .
Bridging ligand Polyfunctional ligands Bridging_ligand > Polyfunctional ligands Polyfunctional ligands can attach to metals in many ways and thus can bridge metals in diverse ways, including sharing of one atom or using several atoms. Examples of such polyatomic ligands are the oxoanions CO2−3 and the related carboxylates, PO3−4, and the polyoxometalates. Several organophosphorus ligands have been developed that bridge pairs of metals, a well-known example being Ph2PCH2PPh2.
Eukaryotic transcription Elongation Eukaryotic_transcription > Elongation After escaping the promoter and shedding most of the transcription factors for initiation, the polymerase acquires new factors for the next phase of transcription: elongation. Transcription elongation is a processive process. Double stranded DNA that enters from the front of the enzyme is unzipped to avail the template strand for RNA synthesis. For every DNA base pair separated by the advancing polymerase, one hybrid RNA:DNA base pair is immediately formed. DNA strands and nascent RNA chain exit from separate channels; the two DNA strands reunite at the trailing end of the transcription bubble while the single strand RNA emerges alone.
Perm (unit) Definitions Perm_(unit) > Definitions U.S. perm The U.S. perm is defined as 1 grain of water vapor per hour, per square foot, per inch of mercury.Metric perm The metric perm (not an SI unit) is defined as 1 gram of water vapor per day, per square meter, per millimeter of mercury.Equivalent SI unit The equivalent SI measure is the nanogram per second per square meter per pascal.The base normal SI unit for permeance is the kilogram per second per square meter per pascal.
Contact homology Research articles Contact_homology > References > Research articles arXiv:math/0611007. doi:10.2140/gt.2007.11.2117. S2CID 119680690.
Circle time Summary Circle_time Circle time provides a time for listening, developing attention span, promoting oral communication, and learning new concepts and skills. It is a time for auditory memory, sensory experiences, socialization, and a time for fun. Circle time can be a complex, dynamic interaction among adults, children, and resources used.
Grid generation Variational methods Mesh_generation > Techniques > Variational methods This method includes a technique that minimizes grid smoothness, orthogonality and volume variation. This method forms mathematical platform to solve grid generation problems. In this method an alternative grid is generated by a new mesh after each iteration and computing the grid speed using backward difference method. This technique is a powerful one with a disadvantage that effort is required to solve the equations related to grid. Further work needed to be done to minimize the integrals that will reduce the CPU time.
Data analysis for fraud detection Machine learning and data mining Data_analysis_techniques_for_fraud_detection > Machine learning and data mining Early data analysis techniques were oriented toward extracting quantitative and statistical data characteristics. These techniques facilitate useful data interpretations and can help to get better insights into the processes behind the data. Although the traditional data analysis techniques can indirectly lead us to knowledge, it is still created by human analysts.To go beyond, a data analysis system has to be equipped with a substantial amount of background knowledge, and be able to perform reasoning tasks involving that knowledge and the data provided. In effort to meet this goal, researchers have turned to ideas from the machine learning field.
Telomerization Nomenclature Telomerization > Nomenclature According to the jargon in polymer chemistry, telomerization requires a telogen to react with at least one unsaturated taxogen molecule. Fluorotelomers are an example.
Hashimoto's thyroiditis Epidemiology Hashimoto_thyroiditis > Epidemiology Hashimoto's thyroiditis disorder is thought to be the most common cause of primary hypothyroidism in North America. Within person, place, and time descriptive trends of epidemiology, it becomes more clear on how Hashimoto's thyroiditis develops in and impacts differing populations.
List of spacetimes Summary List_of_spacetimes This is a list of well-known spacetimes in general relativity. Where the metric tensor is given, a particular choice of coordinates is used, but there are often other useful choices of coordinate available. In general relativity, spacetime is described mathematically by a metric tensor (on a smooth manifold), conventionally denoted g {\displaystyle g} or d s 2 {\displaystyle ds^{2}} .
Index of protein-related articles Medicine Index_of_protein-related_articles > Medicine Tau protein, microtubule-associated protein found in neurons in the brain
SQL Server Analysis Services Data manipulation language (DML) Microsoft_Analysis_Services > Query languages > Data manipulation language (DML) MDX - for querying OLAP cubes LINQ - for querying OLAP cubes from .NET using ADO.NET Entity Framework and Language INtegrated Query (SSAS Entity Framework Provider is required) SQL - small subset of SQL (in form of management views also called as DMV's) for querying OLAP cubes and dimensions as if they were tables DMX - for querying Data Mining models DAX - for querying Tabular models
Decentralized application Trends Decentralized_application > Trends Less than one fifth of DApps capture almost all the DApp users on the Ethereum blockchain. About 5% of DApps capture 80% of Ethereum transactions. 80% of DApps on Ethereum are used by less than 1000 users.
Reaction formation Theory Reaction_formation > Theory Another feature of a reaction formation is its compulsiveness. A person who is defending himself against anxiety cannot deviate from expressing the opposite of what he really feels. His love, for instance, is not flexible.
Circuit element Types Circuit_element > Types Circuit elements can be classified into different categories. One is how many terminals they have to connect them to other components: One-port elements – represent the simplest components, with only two terminals to connect to. Examples are resistances, capacitances, inductances, and diodes. Multiport elements – these have more than two terminals.
Circular mil Square inches Circular_mils > Equivalence to other units of area > Square inches To equate circular mils with square inches rather than square mils, the definition of a mil in inches can be substituted: 1 c m i l = π 4 m i l 2 = π 4 ( 0.001 i n ) 2 = π 4,000,000 i n 2 ≈ 7.854 × 10 − 7 i n 2 {\displaystyle {\begin{aligned}{\rm {1~cmil}}&={\rm {{\frac {\pi }{4}}~mil^{2}={\frac {\pi }{4}}~(0.001~in)^{2}}}\\&={\rm {{\frac {\pi }{4{,}000{,}000}}~in^{2}\approx 7.854\times 10^{-7}~in^{2}}}\end{aligned}}}
ST-elevation myocardial infarction Imaging Myocardial_infarction > Diagnosis > Imaging Noninvasive imaging plays an important role in the diagnosis and characterisation of myocardial infarction. Tests such as chest X-rays can be used to explore and exclude alternate causes of a person's symptoms. Echocardiography may assist in modifying clinical suspicion of ongoing myocardial infarction in patients that can't be ruled out or ruled in following initial ECG and Troponin testing. Myocardial perfusion imaging has no role in the acute diagnostic algorithm; however, it can confirm a clinical suspicion of Chronic Coronary Syndrome when the patient's history, physical examination (including cardiac examination) ECG, and cardiac biomarkers suggest coronary artery disease.Echocardiography, an ultrasound scan of the heart, is able to visualize the heart, its size, shape, and any abnormal motion of the heart walls as they beat that may indicate a myocardial infarction.
Automated systems Advantages, disadvantages, and limitations Automation > Advantages, disadvantages, and limitations Coupled with mechanization, extending human capabilities in terms of size, strength, speed, endurance, visual range & acuity, hearing frequency & precision, electromagnetic sensing & effecting, etc., advantages include: Relieving humans of dangerous work stresses and occupational injuries (e.g., fewer strained backs from lifting heavy objects) Removing humans from dangerous environments (e.g. fire, space, volcanoes, nuclear facilities, underwater, etc.)The main disadvantages of automation are: High initial cost Faster production without human intervention can mean faster unchecked production of defects where automated processes are defective. Scaled-up capacities can mean scaled-up problems when systems fail — releasing dangerous toxins, forces, energies, etc., at scaled-up rates. Human adaptiveness is often poorly understood by automation initiators.
Anacardic acid List of anacardic acids Anacardic_acids > List of anacardic acids 6-pentadecyl salicylic acid (6-PDSA), a potent HAT inhibitor from cashew nut shell liquid, and sensitizer of cancer cells to ionizing radiation.
Energy dispersal Description Energy_dispersal > Description Increase of entropy in a thermodynamic process can be described in terms of "energy dispersal" and the "spreading of energy," while avoiding mention of "disorder" except when explaining misconceptions. All explanations of where and how energy is dispersing or spreading have been recast in terms of energy dispersal, so as to emphasise the underlying qualitative meaning.In this approach, the second law of thermodynamics is introduced as "Energy spontaneously disperses from being localized to becoming spread out if it is not hindered from doing so," often in the context of common experiences such as a rock falling, a hot frying pan cooling down, iron rusting, air leaving a punctured tyre and ice melting in a warm room. Entropy is then depicted as a sophisticated kind of "before and after" yardstick — measuring how much energy is spread out over time as a result of a process such as heating a system, or how widely spread out the energy is after something happens in comparison with its previous state, in a process such as gas expansion or fluids mixing (at a constant temperature). The equations are explored with reference to the common experiences, with emphasis that in chemistry the energy that entropy measures as dispersing is the internal energy of molecules.
AT Multiuser System Peripherals PC_AT > Features > Peripherals The AT included the AT keyboard, initially a new 84-key layout (the 84th key being SysRq). The numerical keypad was now clearly separated from the main key group, and indicator LEDs were added for Caps Lock, Scroll Lock and Num Lock. The AT keyboard uses the same 5-pin DIN connector as the PC keyboard, but a different, bidirectional electrical interface with different keyboard scan codes. The bidirectional interface allows the computer to set the LED indicators on the keyboard, reset the keyboard, set the typematic rate, and other features.
Sex differences in cognition Working memory Sex_differences_in_cognition > Sex differences in memory > Working memory The authors of the study state: "Results indicated sex effects at high loads across tasks and within each task, such that males had higher accuracy, even among groups that were matched for performance at lower loads". A 2006 review and study on working memory published in the journal European Journal of Cognitive Psychology also found no sex differences in working memory processes except in a double-span task where females outperformed males. There have also been no sex differences found in a popular working memory task known as n-back among a large number of studies.
Components of jet engines Hydromechanical unit (HMU) Air_inlet > Major components > Fuel system > Hydromechanical unit (HMU) The HMU has to implement the following: the variable restriction (called the fuel metering valve FMV) and the pressure drop across it (by using a bypass valve between the high pressure fuel pump and the FMV). The pressure drop is kept constant so the fuel flow to the fuel nozzle only depends on the FMV position. The pilot's thrust lever request for fuel is only one request that goes into the FADEC to position the FMV. Others, such as the HP rotor speed, will modify the pilot's request as necessary before sending a signal to the torque motor which sets the position of the FMV. The HMU also sends fuel hydraulic signals using FADEC-controlled individual torque motors to actuators for the variable stator vanes, low and high pressure turbine clearance control, high pressure compressor clearance control and a motor for the variable bleed valves.
Mathematical operator Summary Mathematical_operator The most basic operators are linear maps, which act on vector spaces. Linear operators refer to linear maps whose domain and range are the same space, for example R n {\displaystyle \mathbb {R} ^{n}} to R n {\displaystyle \mathbb {R} ^{n}} . Such operators often preserve properties, such as continuity.
Unhexoctium Predicted structures of an extended periodic table Unoctnilium > Predicted structures of an extended periodic table There is currently no consensus on the placement of elements beyond atomic number 120 in the periodic table. All of these hypothetically undiscovered elements are named by the International Union of Pure and Applied Chemistry (IUPAC) systematic element name standard which creates a generic name for use until the element has been discovered, confirmed, and an official name approved. These names are typically not used in the literature, and are referred to by their atomic numbers; hence, element 164 would usually not be called "unhexquadium" or "Uhq" (the IUPAC systematic name and symbol), but rather "element 164" with symbol "164", "(164)", or "E164".
Young modulus Linear versus non-linear Young’s_modulus > Usage > Linear versus non-linear Young's modulus represents the factor of proportionality in Hooke's law, which relates the stress and the strain. However, Hooke's law is only valid under the assumption of an elastic and linear response. Any real material will eventually fail and break when stretched over a very large distance or with a very large force; however, all solid materials exhibit nearly Hookean behavior for small enough strains or stresses. If the range over which Hooke's law is valid is large enough compared to the typical stress that one expects to apply to the material, the material is said to be linear.
Circuit topology (electrical) History Circuit_topology_(electrical) > Graph theory > History Veblen is also responsible for the introduction of the spanning tree to aid choosing a compatible set of network variables. Comprehensive cataloguing of network graphs as they apply to electrical circuits began with Percy MacMahon in 1891 (with an engineer friendly article in The Electrician in 1892) who limited his survey to series and parallel combinations. MacMahon called these graphs yoke-chains.
Influence line Summary Influence_line For a concentrated (or point) load, a unit point load is moved along the structure. For a distributed load of a given width, a unit-distributed load of the same width is moved along the structure, noting that as the load nears the ends and moves off the structure only part of the total load is carried by the structure. The effect of the distributed unit load can also be obtained by integrating the point load's influence line over the corresponding length of the structures. The Influence lines of determinate structures becomes a mechanism whereas the Influence lines of indeterminate structures become just determinate.
Classical Lie group The classical groups Classical_Lie_group > The classical groups The classical groups are exactly the general linear groups over R, C and H together with the automorphism groups of non-degenerate forms discussed below. These groups are usually additionally restricted to the subgroups whose elements have determinant 1, so that their centers are discrete. The classical groups, with the determinant 1 condition, are listed in the table below.
Dimension Data Cybersecurity Dimension_Data > Products and services > Cybersecurity Dimension Data provides cybersecurity for businesses on an enterprise scale. This includes infrastructure security, governance and compliance, risk assessment, and a variety of other cybersecurity services. It also offers services for mobile security and data leakage prevention.

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