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Vitamin K antagonist Coumarins (4-hydroxycoumarins) Vitamin_K_antagonist_rodenticide > Coumarins (4-hydroxycoumarins) Eventually some rodents developed resistance to it. The "second generation" VKAs for dedicated use as rodenticides are sometimes called superwarfarins. These VKAs are enhanced to kill warfarin-resistant rodents.
Sort algorithms Others Sorting_Algorithm > Comparison of algorithms > Others A randomized integer sorting algorithm taking O ( n log ⁡ log ⁡ n ) {\displaystyle O\left(n{\sqrt {\log \log n}}\right)} expected time and O(n) space. One of the authors of the previously mentioned algorithm also claims to have discovered an algorithm taking O ( n log ⁡ n ) {\displaystyle O\left(n{\sqrt {\log n}}\right)} time and O(n) space, sorting real numbers. Further claiming that, without any added assumptions on the input, it can be modified to achieve O ( n log ⁡ n / log ⁡ log ⁡ n ) {\displaystyle O\left(n\log n/{\sqrt {\log \log n}}\right)} time and O(n) space.
Resorcinarene Structure Resorcinarene > Structure (Isobutylpyrogallolarene)6 is held together by 48 intermolecular hydrogen bonds. The remaining 24 hydrogen bonds are intramolecular. The cavity is filled by solvent.
247 (number) Summary 247_(number) palindromic in base 18 (DD18). a Harshad number in bases 10, 14, 19, 20, 27, 39, 40, 58, 77, 79, 115, 118, 229 and 235. the smallest number which can be expressed as the difference between two integers that contain together all the decimal digits 0–9. i.e. 247 = 50123 - 49876. == References ==
Einstein's thought experiments Falling painters and accelerating elevators Einstein's_thought_experiments > General relativity > Falling painters and accelerating elevators The chamber begins to move "upwards" with a uniformly accelerated motion. Within the chamber, all of the man's perceptions are consistent with his being in a uniform gravitational field. Einstein asked, "Ought we to smile at the man and say that he errs in his conclusion?"
Crystal protein Temperature Protein_crystal > Factors influencing protein crystallization > Temperature Temperature is another interesting parameter to discuss since protein solubility is a function of temperature. In protein crystallization, manipulation of temperature to yield successful crystals is one common strategy. Unlike pH, temperature of different components of the crystallography experiments could impact the final results such as temperature of buffer preparation, temperature of the actual crystallization experiment, etc.
Markov model Markov chain Markov_model > Markov chain The simplest Markov model is the Markov chain. It models the state of a system with a random variable that changes through time. In this context, the Markov property suggests that the distribution for this variable depends only on the distribution of a previous state. An example use of a Markov chain is Markov chain Monte Carlo, which uses the Markov property to prove that a particular method for performing a random walk will sample from the joint distribution.
Classifier constructions in sign languages Summary Classifier_constructions_in_sign_languages In sign languages, the term classifier construction (also known as classifier predicates) refers to a morphological system that can express events and states. They use handshape classifiers to represent movement, location, and shape. Classifiers differ from signs in their morphology, namely in that signs consist of a single morpheme. Signs are composed of three meaningless phonological features: handshape, location, and movement.
Undefined (mathematics) Values for which functions are undefined Undefined_(mathematics) > Values for which functions are undefined The set of numbers for which a function is defined is called the domain of the function. If a number is not in the domain of a function, the function is said to be "undefined" for that number. Two common examples are f ( x ) = 1 x {\textstyle f(x)={\frac {1}{x}}} , which is undefined for x = 0 {\displaystyle x=0} , and f ( x ) = x {\displaystyle f(x)={\sqrt {x}}} , which is undefined (in the real number system) for negative x {\displaystyle x} .
Personal Information Management Managing privacy and the flow of information Personal_Information_Management > Research > Managing privacy and the flow of information People face a continual evaluation of tradeoffs in deciding what information "flows" into and out of their PSI. Each interaction poses some degree of risk to privacy and security. Letting out information to the wrong recipients can lead to identity theft. Letting in the wrong kind of information can mean that a person's devices are "infected" and the person's data is corrupted or "locked" for ransom.
Local variables, recursion and reentrancy Libraries Algorithm_function > Libraries Even with this cumbersome approach, subroutines proved very useful. They allowed the use of the same code in many different programs. Memory was a very scarce resource on early computers, and subroutines allowed significant savings in the size of programs. Many early computers loaded the program instructions into memory from a punched paper tape.
Kepler-40 Summary Kepler-40 Kepler-40, formerly known as KOI-428, is an F-type star in the constellation Cygnus. Kepler-40 is known to host at least one planet, Kepler-40b. The star is approximately 1.5 times more massive than the Sun, and is over two times its size; it was, at upon its discovery, the largest yet discovered with a transiting planet in its orbit. Kepler-40 was first noted as home to a possible transiting object by the Kepler spacecraft; the data on the system was released to the public. A team of French and Swiss scientists used follow-up data to determine the existence of the Hot Jupiter planet Kepler-40b, and later had their results published in a scientific journal on January 4, 2011.
Systemic corticosteroids Adverse effects Nasal_steroid > Adverse effects Therapeutically, the bulk of corticosteroid dose is given in the morning to mimic the body's diurnal rhythm; if given at night, the feeling of being energized will interfere with sleep. An extensive review is provided by Flores and Gumina. Cardiovascular: Corticosteroids can cause sodium retention through a direct action on the kidney, in a manner analogous to the mineralocorticoid aldosterone.
Discrete space Summary Discrete_uniform_space In topology, a discrete space is a particularly simple example of a topological space or similar structure, one in which the points form a discontinuous sequence, meaning they are isolated from each other in a certain sense. The discrete topology is the finest topology that can be given on a set. Every subset is open in the discrete topology so that in particular, every singleton subset is an open set in the discrete topology.
Continuous map Construction of continuous functions Continuous_(topology) > Real functions > Construction of continuous functions The same holds for the product of continuous functions, (defined by p ( x ) = f ( x ) ⋅ g ( x ) {\displaystyle p(x)=f(x)\cdot g(x)} for all x ∈ D {\displaystyle x\in D} ) is continuous in D . {\displaystyle D.} Combining the above preservations of continuity and the continuity of constant functions and of the identity function I ( x ) = x {\displaystyle I(x)=x} on R {\displaystyle \mathbb {R} } , one arrives at the continuity of all polynomial functions on R {\displaystyle \mathbb {R} } , such as (pictured on the right).
Amitifadine Pharmacology Amitifadine > Pharmacology Ki values for SERT, NET, and DAT of amitifadine are 99 nM, 262 nM, and 213 nM. The IC50 values for serotonin, norepinephrine and dopamine uptake are 12, 23 and 96 nM, respectively Amitifadine reduces the duration of immobility in the forced swim test in rats with an oral minimum effective dose (MED) of 5 mg/kg. This antidepressant-like effect manifests in the absence of significant increases in motor activity at doses of up to 20 mg/kg.
Kepler-14b Host star system Kepler-14b > Host star system Kepler-14 is a binary star system, which means that it is actually composed of two gravitationally bound stars that orbit a common point in space. The system is composed of a primary star, Kepler-14A, and a dimmer companion star, Kepler-14B. When the stars were observed, while searching for the planet Kepler-14b, the angular separation of the binary system made it extremely difficult to note the dimmer companion star. The stars have such a wide orbit that it takes approximately 2800 years for each star to complete a revolution around the centroid.
Shading language Summary Shading_language A shading language is a graphics programming language adapted to programming shader effects. Shading languages usually consist of special data types like "vector", "matrix", "color" and "normal".
Dielectric Capacitors Dipolar_polarization > Applications > Capacitors In this case the charge density is given by and the capacitance per unit area by From this, it can easily be seen that a larger ε leads to greater charge stored and thus greater capacitance. Dielectric materials used for capacitors are also chosen such that they are resistant to ionisation. This allows the capacitor to operate at higher voltages before the insulating dielectric ionises and begins to allow undesirable current.
Embryoid body Differentiation within EBs Embryoid_body > Differentiation within EBs Additionally, the inductive effects resulting from signaling between cell populations in EBs results in spatially and temporally defined changes, which promote complex morphogenesis. Tissue-like structures are often exhibited within EBs, including the appearance of blood islands reminiscent of early blood vessel structures in the developing embryo, as well as the patterning of neurite extensions (indicative of neuron organization) and spontaneous contractile activity (indicative of cardiomyocyte differentiation) when EBs are plated onto adhesive substrates such as gelatin. More recently, complex structures, including optic cup-like structures were created in vitro resulting from EB differentiation.
Cingulate cortex Anterior cingulate cortex Cingulate_gyrus > Structure > Anterior cingulate cortex The mamillary neurons receive axons from the subiculum. The whole forms a neural circuit in the limbic system known as the Papez circuit. The anterior cingulate cortex sends axons to the anterior nucleus and through the cingulum to other Broca's limbic areas. The ACC is involved in error and conflict detection processes.
Viscous stress tensor Viscous versus elastic stress Viscous_stress_tensor > Definition > Viscous versus elastic stress Internal mechanical stresses in a continuous medium are generally related to deformation of the material from some "relaxed" (unstressed) state. These stresses generally include an elastic ("static") stress component, that is related to the current amount of deformation and acts to restore the material to its rest state; and a viscous stress component, that depends on the rate at which the deformation is changing with time and opposes that change.
Franssen effect Franssen effect F1 Franssen_effect > Franssen effect F1 There are two loudspeakers to the left and right of the listener. Each is about 1 meter in distance from the listener, at approximately 45° angles. The left speaker suddenly begins to produce a sharp pure tone.
Local case-control sampling Summary Local_case-control_sampling In practice, the pilot may come from prior knowledge or training using a subsample of the dataset. The algorithm is most effective when the underlying dataset is imbalanced. It exploits the structures of conditional imbalanced datasets more efficiently than alternative methods, such as case control sampling and weighted case control sampling.
Primary myelofibrosis Mechanism Primary_myelofibrosis > Mechanism Myelofibrosis is a clonal neoplastic disorder of hematopoiesis, the formation of blood cellular components. It is one of the myeloproliferative disorders, diseases of the bone marrow in which excess cells are produced at some stage. Production of cytokines such as fibroblast growth factor by the abnormal hematopoietic cell clone (particularly by megakaryocytes) leads to replacement of the hematopoietic tissue of the bone marrow by connective tissue via collagen fibrosis. The decrease in hematopoietic tissue impairs the patient's ability to generate new blood cells, resulting in progressive pancytopenia, a shortage of all blood cell types.
Chronic myeloid leukaemia Pathophysiology Chronic_Myelogenous_Leukemia > Pathophysiology CML was the first cancer to be linked to a clear genetic abnormality, the chromosomal translocation known as the Philadelphia chromosome. This chromosomal abnormality is so named because it was first discovered and described in 1960 by two scientists from Philadelphia, Pennsylvania, USA: Peter Nowell of the University of Pennsylvania and David Hungerford of Fox Chase Cancer Center.In this translocation, parts of two chromosomes (the 9th and 22nd) switch places. As a result, part of the BCR ("breakpoint cluster region") gene from chromosome 22 is fused with the ABL gene on chromosome 9. This abnormal "fusion" gene generates a protein of p210 or sometimes p185 weight (p210 is short for 210 kDa protein, a shorthand used for characterizing proteins based solely on size).
Dynamo-electric machine Summary Dynamo-electric_machine A dynamo is an electrical generator that creates direct current using a commutator. Dynamos were the first electrical generators capable of delivering power for industry, and the foundation upon which many other later electric-power conversion devices were based, including the electric motor, the alternating-current alternator, and the rotary converter. Today, the simpler alternator dominates large scale power generation, for efficiency, reliability and cost reasons. A dynamo has the disadvantages of a mechanical commutator. Also, converting alternating to direct current using rectifiers (such as vacuum tubes or more recently via solid state technology) is effective and usually economical.
Multiple regression analysis Regression model Regression_equation > Regression model Using this estimate, the researcher can then use the fitted value Y i ^ = f ( X i , β ^ ) {\displaystyle {\hat {Y_{i}}}=f(X_{i},{\hat {\beta }})} for prediction or to assess the accuracy of the model in explaining the data. Whether the researcher is intrinsically interested in the estimate β ^ {\displaystyle {\hat {\beta }}} or the predicted value Y i ^ {\displaystyle {\hat {Y_{i}}}} will depend on context and their goals. As described in ordinary least squares, least squares is widely used because the estimated function f ( X i , β ^ ) {\displaystyle f(X_{i},{\hat {\beta }})} approximates the conditional expectation E ( Y i \| X i ) {\displaystyle E(Y_{i}\|X_{i})} .
Mathematical formulation of quantum mechanics Time as an operator Mathematical_formulations_of_quantum_mechanics > Mathematical structure of quantum mechanics > Time as an operator The framework presented so far singles out time as the parameter that everything depends on. It is possible to formulate mechanics in such a way that time becomes itself an observable associated with a self-adjoint operator. At the classical level, it is possible to arbitrarily parameterize the trajectories of particles in terms of an unphysical parameter s, and in that case the time t becomes an additional generalized coordinate of the physical system. At the quantum level, translations in s would be generated by a "Hamiltonian" H − E, where E is the energy operator and H is the "ordinary" Hamiltonian.
Randomness Summary Randomness For example, with a bowl containing just 10 red marbles and 90 blue marbles, a random selection mechanism would choose a red marble with probability 1/10. A random selection mechanism that selected 10 marbles from this bowl would not necessarily result in 1 red and 9 blue. In situations where a population consists of items that are distinguishable, a random selection mechanism requires equal probabilities for any item to be chosen.
Unbiased estimation of standard deviation Estimating the standard deviation of the population Unbiased_estimation_of_standard_deviation > Effect of autocorrelation (serial correlation) > Estimating the standard deviation of the population As with c4, θ approaches unity as the sample size increases (as does γ1). It can be demonstrated via simulation modeling that ignoring θ (that is, taking it to be unity) and using E ≈ σ γ 1 ⇒ σ ^ ≈ s γ 1 {\displaystyle {\rm {E}}\approx \sigma {\sqrt {\gamma _{1}}}\Rightarrow {\hat {\sigma }}\approx {\frac {s}{\sqrt {\gamma _{1}}}}} removes all but a few percent of the bias caused by autocorrelation, making this a reduced-bias estimator, rather than an unbiased estimator. In practical measurement situations, this reduction in bias can be significant, and useful, even if some relatively small bias remains. The figure above, showing an example of the bias in the standard deviation vs. sample size, is based on this approximation; the actual bias would be somewhat larger than indicated in those graphs since the transformation bias θ is not included there.
Doubly linked list Deleting a node Doubly_linked_list > Basic algorithms > Circular doubly linked lists > Deleting a node As in doubly linked lists, "removeAfter" and "removeBefore" can be implemented with "remove(list, node.prev)" and "remove(list, node.next)".
Designer babies CRISPR/Cas9 Designer_baby > Human germline engineering > CRISPR/Cas9 This means it is often used in knockout experiments to disrupt genes and introduce loss of function mutations. Homology Directed Repair (HDR) - a less efficient but high-fidelity process which is used to introduce precise modifications into the target sequence. The process requires adding a DNA repair template including a desired sequence, which the cell's machinery uses to repair the DSB, incorporating the sequence of interest into the genome.Since NHEJ is more efficient than HDR, most DSBs will be repaired via NHEJ, introducing gene knockouts.
Cache control instruction Vector fetch Cache_control_instruction > Alternatives > Vector fetch Vector processors (for example modern graphics processing unit (GPUs) and Xeon Phi) use massive parallelism to achieve high throughput whilst working around memory latency (reducing the need for prefetching). Many read operations are issued in parallel, for subsequent invocations of a compute kernel; calculations may be put on hold awaiting future data, whilst the execution units are devoted to working on data from past requests data that has already turned up. This is easier for programmers to leverage in conjunction with the appropriate programming models (compute kernels), but harder to apply to general purpose programming. The disadvantage is that many copies of temporary states may be held in the local memory of a processing element, awaiting data in flight. == References ==
Ecological light pollution Natural light cycles Ecological_light_pollution > Natural light cycles The introduction of artificial light disrupts several natural light cycles that arise from the movements of the Earth, Moon, and Sun, as well as from meteorological factors.
Richard Jenkins (engineer) World land speed record Richard_Jenkins_(engineer) > World land speed record "Top speed is actually quite scary. The structure and tyre grip is all at the limit, so keeping it in a straight line under full control takes full concentration," Jenkins told The Guardian.Greenbird is the fifth iteration of the land yacht that was first known as Windjet. Greenbird is powered by a carbon composite wing that produces thrust similarly to how an airplane wing produces lift.Jenkins attempted to break the world record for sailing on ice on the frozen Canyon Ferry Reservoir in Montana with a vehicle adapted for ice.
Sulfur isotope biogeochemistry Fractionation factors Sulfur_isotope_biogeochemistry > Calculations > Fractionation factors While an isotope effect is the physical tendency for stable isotopes to distribute in a particular way, the isotopic fractionation is the measurable result of this tendency. The isotopic fractionation of a natural process can be calculated from measured isotope abundances. The calculated value is called a "fractionation factor," and allows the effect of different processes on isotope distributions to be mathematically compared. For example, imagine a chemical reaction Reactant → Product.
Pulmonary thromboendarterectomy Description of the surgery Pulmonary_thromboendarterectomy > Description of the surgery Circulatory arrest is limited to 20 minute intervals to protect brain function. Typically an experienced surgeon can perform an entire unilateral procedure in this time.
First law of thermodynamics Original statements: the "thermodynamic approach" First_law_of_thermodynamics > History > Original statements: the "thermodynamic approach" It is defined only up to an arbitrary additive constant of integration, which can be adjusted to give arbitrary reference zero levels. This non-uniqueness is in keeping with the abstract mathematical nature of the internal energy.
Abscisic acid Signal cascade Abscissic_acid > In plants > Signal cascade When SnRK2s are released from inhibition, they activate several transcription factors from the ABA RESPONSIVE ELEMENT-BINDING FACTOR (ABF) family. ABFs then go on to cause changes in the expression of a large number of genes. Around 10% of plant genes are thought to be regulated by ABA.
Amphetamine Serotonin Amphetamine > Pharmacology > Pharmacodynamics > Serotonin Amphetamine exerts analogous, yet less pronounced, effects on serotonin as on dopamine and norepinephrine. Amphetamine affects serotonin via VMAT2 and, like norepinephrine, is thought to phosphorylate SERT via TAAR1. Like dopamine, amphetamine has low, micromolar affinity at the human 5-HT1A receptor.
Biological psychiatry Scope of clinical biological psychiatric treatment Biological_psychiatry > Scope of clinical biological psychiatric treatment Since various biological factors can affect mood and behavior, psychiatrists often evaluate these before initiating further treatment. For example, dysfunction of the thyroid gland may mimic a major depressive episode, or hypoglycemia (low blood sugar) may mimic psychosis.While pharmacological treatments are used to treat many mental disorders, other non-drug biological treatments are used as well, ranging from changes in diet and exercise to transcranial magnetic stimulation and electroconvulsive therapy. Types of non-biological treatments such as cognitive therapy, behavioral therapy, and psychodynamic psychotherapy are often used in conjunction with biological therapies. Biopsychosocial models of mental illness are widely in use, and psychological and social factors play a large role in mental disorders, even those with an organic basis such as schizophrenia.
Pulse-Doppler radar Benefits Pulse-Doppler_radar > Principle > Benefits Surface reflections appear in almost all radar. Ground clutter generally appears in a circular region within a radius of about 25 miles (40 km) near ground-based radar. This distance extends much further in airborne and space radar.
Circulatory shock Summary Shock_(circulatory) Efforts to maintain a normal body temperature are also important. Vasopressors may be useful in certain cases. Shock is both common and has a high risk of death. In the United States about 1.2 million people present to the emergency room each year with shock and their risk of death is between 20 and 50%.
Statistical assumption Classes of assumptions Statistical_assumption > Classes of assumptions Cross-variation assumptions. These assumptions involve the joint probability distributions of either the observations themselves or the random errors in a model. Simple models may include the assumption that observations or errors are statistically independent.
Dielectric strength Electrical breakdown Dielectric_strength > Electrical breakdown Electric current is a flow of electrically charged particles in a material caused by an electric field. The mobile charged particles responsible for electric current are called charge carriers. In different substances different particles serve as charge carriers: in metals and other solids some of the outer electrons of each atom (conduction electrons) are able to move about the material; in electrolytes and plasma it is ions, electrically charged atoms or molecules, and electrons. A substance that has a high concentration of charge carriers available for conduction will conduct a large current with the given electric field created by a given voltage applied across it, and thus has a low electrical resistivity; this is called an electrical conductor.
Toll-like receptor 7 Clinical significance Toll-like_receptor_7 > Clinical significance This suggests that TLR7 plays a key role in triggering the immune response for patients of COVID-19. For more details on the biological mechanism and pathway, see "Type I Interferon Induction and Signaling During SARS-CoV-2 Infection" on WikiPathways. In contrast, gain-of-function variation in TLR7 was shown in 2022 to cause systemic lupus erythematous and neuromyelitis optica in humans.
Bode plotter Rules for handmade Bode plot Bode_Plot > Rules for handmade Bode plot For many practical problems, the detailed Bode plots can be approximated with straight-line segments that are asymptotes of the precise response. The effect of each of the terms of a multiple element transfer function can be approximated by a set of straight lines on a Bode plot. This allows a graphical solution of the overall frequency response function. Before widespread availability of digital computers, graphical methods were extensively used to reduce the need for tedious calculation; a graphical solution could be used to identify feasible ranges of parameters for a new design.
Pythagoras Communal lifestyle Pythagoras > Pythagoreanism > Communal lifestyle Ancient sources record that the Pythagoreans ate meals in common after the manner of the Spartans. One Pythagorean maxim was "koinà tà phílōn" ("All things in common among friends"). Both Iamblichus and Porphyry provide detailed accounts of the organization of the school, although the primary interest of both writers is not historical accuracy, but rather to present Pythagoras as a divine figure, sent by the gods to benefit humankind.
Transcription-translation coupling Summary Transcription-translation_coupling Transcription-translation coupling is a mechanism of gene expression regulation in which synthesis of an mRNA (transcription) is affected by its concurrent decoding (translation). In prokaryotes, mRNAs are translated while they are transcribed. This allows communication between RNA polymerase, the multisubunit enzyme that catalyzes transcription, and the ribosome, which catalyzes translation. Coupling involves both direct physical interactions between RNA polymerase and the ribosome ("expressome" complexes), as well as ribosome-induced changes to the structure and accessibility of the intervening mRNA that affect transcription ("attenuation" and "polarity").
Object Pascal Summary Object_Pascal Object Pascal is an extension to the programming language Pascal that provides object-oriented programming (OOP) features such as classes and methods. The language was originally developed by Apple Computer as Clascal for the Lisa Workshop development system. As Lisa gave way to Macintosh, Apple collaborated with Niklaus Wirth, the author of Pascal, to develop an officially standardized version of Clascal. This was renamed Object Pascal.
Runtime verification Reducing runtime overhead Runtime_verification > Research challenges and applications > Reducing runtime overhead Observing an executing system typically incurs some runtime overhead (hardware monitors may make an exception). It is important to reduce the overhead of runtime verification tools as much as possible, particularly when the generated monitors are deployed with the system. Runtime overhead reducing techniques include: Improved instrumentation. Extracting events from the executing system and sending them to monitors can generate a large runtime overhead if done naively.
Blockchain-based remittances company United States Blockchain-based_remittances_company > By region > North America > United States construction industry, tighter border controls, and a crackdown in the U.S. on illegal immigration.Remittance culture in the United States has contributed to the formation of "micro-geographies", tightly knit networks that integrate U.S. communities with communities throughout Latin America, such as migrants from Oaxaca, Mexico, who have settled in Venice Beach, California.
Matching transformer Other applications Telephone_balance_unit > Applications > Other applications In power line communications, baluns are used in coupling signals onto a power line. In electronic communications, baluns convert Twinax cables to Cat 5 cables, and back.
Homotopy theory Cofibration and fibration Homotopy_theory > Concepts > Cofibration and fibration A map f: A → X {\displaystyle f:A\to X} is called a cofibration if given (1) a map h 0: X → Z {\displaystyle h_{0}:X\to Z} and (2) a homotopy g t: A → Z {\displaystyle g_{t}:A\to Z} , there exists a homotopy h t: X → Z {\displaystyle h_{t}:X\to Z} that extends h 0 {\displaystyle h_{0}} and such that h t ∘ f = g t {\displaystyle h_{t}\circ f=g_{t}} . To some loose sense, it is an analog of the defining diagram of an injective module in abstract algebra. The most basic example is a CW pair ( X , A ) {\displaystyle (X,A)} ; since many work only with CW complexes, the notion of a cofibration is often implicit.
Statistical inference Likelihood-based inference Inferential_statistics > Paradigms for inference > Likelihood-based inference Likelihood-based inference is a paradigm used to estimate the parameters of a statistical model based on observed data. Likelihoodism approaches statistics by using the likelihood function, denoted as L ( θ \| x ) {\displaystyle L(\theta \|x)} , quantifies the probability of observing the given data x {\displaystyle x} , assuming a specific set of parameter values θ {\displaystyle \theta } . In likelihood-based inference, the goal is to find the set of parameter values that maximizes the likelihood function, or equivalently, maximizes the probability of observing the given data. The process of likelihood-based inference usually involves the following steps: Formulating the statistical model: A statistical model is defined based on the problem at hand, specifying the distributional assumptions and the relationship between the observed data and the unknown parameters.
Darwinian algorithm Summary Speciation_(genetic_algorithm) In computer science and operations research, a genetic algorithm (GA) is a metaheuristic inspired by the process of natural selection that belongs to the larger class of evolutionary algorithms (EA). Genetic algorithms are commonly used to generate high-quality solutions to optimization and search problems by relying on biologically inspired operators such as mutation, crossover and selection. Some examples of GA applications include optimizing decision trees for better performance, solving sudoku puzzles, hyperparameter optimization, causal inference, etc.
Mechanical amplifier Swing analogy Mechanical_amplifier > Resonating amplifiers > Parametric resonators > Swing analogy Direct resonance can be equated to someone pushing a child on a swing. If the frequency of the pushing (external forcing) matches the natural frequency of the child-swing system, direct resonance can be achieved. Parametric resonance, on the other hand, is the child shifting his/her own weight with time (twice the frequency of the natural frequency) and building up the oscillatory amplitude of the swing without anyone helping to push. In other words, there is an internal transfer of energy (instead of simply dissipating all available energy) as the system parameter (child's weight) modulates and changes with time.
Hermitian matrix Diagonalizable Hermitian_matrix > Properties > Diagonalizable The finite-dimensional spectral theorem says that any Hermitian matrix can be diagonalized by a unitary matrix, and that the resulting diagonal matrix has only real entries. This implies that all eigenvalues of a Hermitian matrix A with dimension n are real, and that A has n linearly independent eigenvectors. Moreover, a Hermitian matrix has orthogonal eigenvectors for distinct eigenvalues. Even if there are degenerate eigenvalues, it is always possible to find an orthogonal basis of Cn consisting of n eigenvectors of A.
Complex contagion Summary Complex_contagion Complex contagion is the phenomenon in social networks in which multiple sources of exposure to an innovation are required before an individual adopts the change of behavior. It differs from simple contagion in that unlike a disease, it may not be possible for the innovation to spread after only one incident of contact with an infected neighbor. The spread of complex contagion across a network of people may depend on many social and economic factors; for instance, how many of one's friends adopt the new idea as well as how many of them cannot influence the individual, as well as their own disposition in embracing change.
Native code Programs Machine_instruction > Programs As an example, the original Intel Pentium from 1993 can execute at most two instructions per clock cycle when its pipeline is full. Program flow may be influenced by special 'jump' instructions that transfer execution to an address (and hence instruction) other than the next numerically sequential address. Whether these conditional jumps occur is dependent upon a condition such as a value being greater than, less than, or equal to another value.
Nervous system network models Summary Nervous_system_network_models Neural network), Computational neuroscience, as well as in several books by Ascoli, G. A. (2002), Sterratt, D., Graham, B., Gillies, A., & Willshaw, D.
Shinumo Quartzite Sedimentary structures Shinumo_Quartzite > Sedimentary structures The beds that exhibit these soft-sediment deformation structures are meters- to tens-of-meters thick. They are cited as evidence for frequent earthquake activity and fluid migration during the deposition of the Shinumo Quartzite. These deformed beds can be seen at river level in the vicinity of Nevilles Rapid, (List of Colorado River rapids), at river mile 75.
Boomerang attack The attack Boomerang_attack > The attack The boomerang attack is based on differential cryptanalysis. In differential cryptanalysis, an attacker exploits how differences in the input to a cipher (the plaintext) can affect the resultant difference at the output (the ciphertext). A high probability "differential" (that is, an input difference that will produce a likely output difference) is needed that covers all, or nearly all, of the cipher. The boomerang attack allows differentials to be used which cover only part of the cipher.
Photoelectric cells Summary Low_cost_solar_cell The separation of charge carriers of opposite types. The separate extraction of those carriers to an external circuit.In contrast, a solar thermal collector supplies heat by absorbing sunlight, for the purpose of either direct heating or indirect electrical power generation from heat. A "photoelectrolytic cell" (photoelectrochemical cell), on the other hand, refers either to a type of photovoltaic cell (like that developed by Edmond Becquerel and modern dye-sensitized solar cells), or to a device that splits water directly into hydrogen and oxygen using only solar illumination. Photovoltaic cells and solar collectors are the two means of producing solar power.
Rheumatic arthritis Mortality Rheumatic_arthritis > Prognosis > Mortality The mechanism by which RA causes this increased risk remains unknown; the presence of chronic inflammation has been proposed as a contributing factor. It is possible that the use of new biologic drug therapies extend the lifespan of people with RA and reduce the risk and progression of atherosclerosis. This is based on cohort and registry studies, and still remains hypothetical. It is still uncertain whether biologics improve vascular function in RA or not. There was an increase in total cholesterol and HDLc levels and no improvement of the atherogenic index.
Weird machine Theory Weird_machine > Theory From a theoretical perspective, the emergence of weird machines becomes clear when one considers software as a way to restrict the number of reachable states and state transitions of a computer: The general-purpose CPU is, through software, specialized to simulate a finite-state machine (with potentially very large state space). Many states the CPU could be in are excluded, and certain state transitions are ruled out - for example those that violate the software's security requirements. When the system is somehow moved into a state that "makes no sense" when viewed from the perspective of the intended finite-state machine (through memory corruption, hardware failure, or other programming mistakes), the software will keep transforming the broken state into new broken states, triggered by further user input. A new computational device arises: The weird machine which can reach different states of the CPU than the programmer anticipated, and which does so in reaction to inputs.
Language transfer Negative transfer Language_transfer > Types of language transfer > Negative transfer Since the German noun "Information" can also be used in the plural – "Informationen" – German students will almost invariably use "informations" in English, too, which would break the rules of uncountable nouns. From a more general standpoint, Brown mentions "all new learning involves transfer based on previous learning". That could also explain why initial learning of L1 will impact L2 acquisition.
The Magnetic Fields History The_Magnetic_Fields > History It was directed by Kerthy Fix and Gail O'Hara. Shot over a period of 10 years, it discusses the formation of the band, Stephin's friendship with Claudia Gonson, the production of various albums, and Stephin's move to California from New York. It won the Outfest 2010 Grand Jury Prize for Feature Documentary.The band was chosen by Jeff Mangum of Neutral Milk Hotel to perform a rare festival performance at the All Tomorrow's Parties event that he curated in March 2012 in Minehead, England.The band released its tenth full-length album, Love at the Bottom of the Sea, on March 6, 2012.
Unit record equipment Sorting Unit_record_equipment > Sorting Sorting an input card deck into ascending sequence on a multiple column field, such as an employee number, was done by a radix sort, bucket sort, or a combination of the two methods. Sorters were also used to separate decks of interspersed master and detail cards, either by a significant hole punch or by the cards corner-cut.More advanced functionality was available in the IBM 101 Electronic Statistical Machine, which could Sort Count Accumulate totals Print summaries Send calculated results (counts and totals) to an attached IBM 524 Duplicating Summary Punch. : pp. 5–6
Home composting Aerobic vs. Anaerobic Home_composting > Fundamentals > Aerobic vs. Anaerobic While aerobic composting does produce some carbon dioxide, anaerobic composting releases methane, which is a greenhouse gas significantly more harmful than carbon dioxide. Aerobic compost is a faster process due to availability of oxygen allowing for growth of composting microorganisms. Aerobic composting calls for larger bins, oxygen, moisture, and turning (only if without worms).
Animal nutrition Protein Animal_nutrition > Constituents of diet > Protein The body requires amino acids to produce new proteins (protein retention) and to replace damaged proteins (maintenance). As there is no protein or amino acid storage provision, amino acids must be present in the diet. Excess amino acids are discarded, typically in the urine.
DNA digital data storage Encoding methods DNA_data_storage > Encoding methods Countless methods for encoding data in DNA are possible. The optimal methods are those that make economical use of DNA and protect against errors. If the message DNA is intended to be stored for a long period of time, for example, 1,000 years, it is also helpful if the sequence is obviously artificial and the reading frame is easy to identify.
Direct bonding Examples Direct_bonding > Examples This technique is usable for the fabrication of multi wafer micro structures, i.e. accelerometers, micro valves and micro pumps.
Optimizing compiler Factors affecting optimization Compiler_analysis > Factors affecting optimization Embedded software can be tightly tuned to an exact CPU and memory size. Also, system cost or reliability may be more important than the code's speed. For example, compilers for embedded software usually offer options that reduce code size at the expense of speed, because memory is the main cost of an embedded computer. The code's timing may need to be predictable, rather than as fast as possible, so code caching might be disabled, along with compiler optimizations that require it.
Nuclear lamina Summary Nuclear_lamina The nuclear lamina is a dense (~30 to 100 nm thick) fibrillar network inside the nucleus of eukaryote cells. It is composed of intermediate filaments and membrane associated proteins. Besides providing mechanical support, the nuclear lamina regulates important cellular events such as DNA replication and cell division. Additionally, it participates in chromatin organization and it anchors the nuclear pore complexes embedded in the nuclear envelope. The nuclear lamina is associated with the inner face of the inner nuclear membrane of the nuclear envelope, whereas the outer face of the outer nuclear membrane is continuous with the endoplasmic reticulum. The nuclear lamina is similar in structure to the nuclear matrix, that extends throughout the nucleoplasm.
Isotope ratio mass spectrometry Summary Isotope-ratio_mass_spectrometry Isotope-ratio mass spectrometry (IRMS) is a specialization of mass spectrometry, in which mass spectrometric methods are used to measure the relative abundance of isotopes in a given sample.This technique has two different applications in the earth and environmental sciences. The analysis of 'stable isotopes' is normally concerned with measuring isotopic variations arising from mass-dependent isotopic fractionation in natural systems. On the other hand, radiogenic isotope analysis involves measuring the abundances of decay-products of natural radioactivity, and is used in most long-lived radiometric dating methods.
Network Security Services Interoperability and open standards Network_Security_Services > Architecture > Interoperability and open standards NSS supports a range of security standards, including the following: TLS 1.0 (RFC 2246), 1.1 (RFC 4346), 1.2 (RFC 5246), and 1.3 (RFC 8446). The Transport Layer Security (TLS) protocol from the IETF supersedes SSL v3.0 while remaining backward-compatible with SSL v3 implementations. SSL 3.0. The Secure Sockets Layer (SSL) protocol allows mutual authentication between a client and server and the establishment of an authenticated and encrypted connection.
Cognitive workload History Cognitive_load_theory > Theory > History The history of cognitive load theory can be traced to the beginning of cognitive science in the 1950s and the work of G.A. Miller. In his classic paper, Miller was perhaps the first to suggest our working memory capacity has inherent limits.
Dopamine Parkinson's disease Dopaminergic_system > Disease, disorders, and pharmacology > Parkinson's disease Parkinson's disease is an age-related disorder characterized by movement disorders such as stiffness of the body, slowing of movement, and trembling of limbs when they are not in use. In advanced stages it progresses to dementia and eventually death. The main symptoms are caused by the loss of dopamine-secreting cells in the substantia nigra. These dopamine cells are especially vulnerable to damage, and a variety of insults, including encephalitis (as depicted in the book and movie "Awakenings"), repeated sports-related concussions, and some forms of chemical poisoning such as MPTP, can lead to substantial cell loss, producing a parkinsonian syndrome that is similar in its main features to Parkinson's disease.
Mortality (computability theory) Summary Mortality_(computability_theory) In computability theory, the mortality problem is a decision problem related to the halting problem. For Turing machines, the halting problem can be stated as follows: Given a Turing machine, and a word, decide whether the machine halts when run on the given word. In contrast, the mortality problem for Turing machines asks whether all executions of the machine, starting from any configuration, halt. In the statement above, a configuration specifies both the machine's state (not necessarily its initial state), its tape position and the contents of the tape.
Pulmonary embolism Fluoroscopic pulmonary angiography Pulmonary_embolism > Diagnosis > Imaging > Fluoroscopic pulmonary angiography Historically, the gold standard for diagnosis was pulmonary angiography by fluoroscopy, but this has fallen into disuse with the increased availability of non-invasive techniques that offer similar diagnostic accuracy.
Circulant matrix Definition Circulant_matrices > Definition The last row of C {\displaystyle C} is the vector c {\displaystyle c} shifted by one in reverse. Different sources define the circulant matrix in different ways, for example as above, or with the vector c {\displaystyle c} corresponding to the first row rather than the first column of the matrix; and possibly with a different direction of shift (which is sometimes called an anti-circulant matrix). The polynomial f ( x ) = c 0 + c 1 x + ⋯ + c n − 1 x n − 1 {\displaystyle f(x)=c_{0}+c_{1}x+\dots +c_{n-1}x^{n-1}} is called the associated polynomial of matrix C {\displaystyle C} .
Control strategy Summary Closed-_loop Control theory was further advanced by Edward Routh in 1874, Charles Sturm and in 1895, Adolf Hurwitz, who all contributed to the establishment of control stability criteria; and from 1922 onwards, the development of PID control theory by Nicolas Minorsky. Although a major application of mathematical control theory is in control systems engineering, which deals with the design of process control systems for industry, other applications range far beyond this. As the general theory of feedback systems, control theory is useful wherever feedback occurs - thus control theory also has applications in life sciences, computer engineering, sociology and operations research.
Drug Master File Types of DMFs Drug_Master_File > Types of DMFs Category: Administrative Subcategories under Administrative Category change in the holder name change in holder address change in ownership of the DMF (either internal name change, or change in ownership) change in the agent name or address. change in the contact person at the holder or agent. change in the subject of the DMF.
Systems research Founding and early development System_theory > History > Founding and early development Subjects that were studied included those of complexity, self-organization, connectionism and adaptive systems. In fields like cybernetics, researchers such as Ashby, Norbert Wiener, John von Neumann, and Heinz von Foerster examined complex systems mathematically; Von Neumann discovered cellular automata and self-reproducing systems, again with only pencil and paper. Aleksandr Lyapunov and Jules Henri Poincaré worked on the foundations of chaos theory without any computer at all.
Turing Test Impracticality and irrelevance: the Turing test and AI research Imitation_game > Weaknesses > Impracticality and irrelevance: the Turing test and AI research "Aeronautical engineering texts," they write, "do not define the goal of their field as 'making machines that fly so exactly like pigeons that they can fool other pigeons. '"Second, creating lifelike simulations of human beings is a difficult problem on its own that does not need to be solved to achieve the basic goals of AI research. Believable human characters may be interesting in a work of art, a game, or a sophisticated user interface, but they are not part of the science of creating intelligent machines, that is, machines that solve problems using intelligence.
Epithelioid sarcoma Immunotherapies Epithelioid_sarcoma > Research > Immunotherapies T-cells can be harvested and then expanded and genetically manipulated to recognize certain tumor markers. In one case, a patient with advanced epithelioid sarcoma who had failed multiple therapies showed a strong response to expanded lymphocytes and natural killer cells.Immune checkpoint inhibitors have recently shown promise against several cancers and may hold promise against sarcomas as well. Tumors often evolve during disease progression, and they can develop an expression of inhibitory proteins that deter recognition by the immune system and allow the tumor to escape immune surveillance. By targeting these inhibitory proteins, a pathway is opened for the immune system to recognize the tumor. Two of these inhibitory proteins that have been studied recently are CTLA-4 and PD1, and drugs targeting these proteins are in development and showing some promise.
Metal carbonyl With electrophiles Infrared_spectroscopy_of_metal_carbonyls > Reactions > With electrophiles Despite being in low formal oxidation states, metal carbonyls are relatively unreactive toward many electrophiles. For example, they resist attack by alkylating agents, mild acids, and mild oxidizing agents. Most metal carbonyls do undergo halogenation. Iron pentacarbonyl, for example, forms ferrous carbonyl halides: Fe(CO)5 + X2 → Fe(CO)4X2 + COMetal–metal bonds are cleaved by halogens. Depending on the electron-counting scheme used, this can be regarded as an oxidation of the metal atoms: Mn2(CO)10 + Cl2 → 2 Mn(CO)5Cl
Computational Anatomy Stationarity of the Hamiltonian and kinetic energy along Euler–Lagrange Computational_Anatomy > Hamiltonian formulation of computational anatomy > Stationarity of the Hamiltonian and kinetic energy along Euler–Lagrange Defining the geodesic velocity at the identity v 0 = arg ⁡ max v H ( ϕ 0 , p 0 , v ) {\displaystyle v_{0}=\arg \max _{v}H(\phi _{0},p_{0},v)} , then along the geodesic The stationarity of the Hamiltonian demonstrates the interpretation of the Lagrange multiplier as momentum; integrated against velocity ϕ ˙ {\displaystyle {\dot {\phi }}} gives energy density. The canonical momentum has many names. In optimal control, the flows ϕ {\displaystyle \phi } is interpreted as the state, and p {\displaystyle p} is interpreted as conjugate state, or conjugate momentum. The geodesi of EL implies specification of the vector fields v 0 {\displaystyle v_{0}} or Eulerian momentum A v 0 {\displaystyle Av_{0}} at t = 0 {\displaystyle t=0} , or specification of canonical momentum p 0 {\displaystyle p_{0}} determines the flow.
Turing Test Summary Turing_Test Turing's new question is: "Are there imaginable digital computers which would do well in the imitation game?" This question, Turing believed, was one that could actually be answered. In the remainder of the paper, he argued against all the major objections to the proposition that "machines can think".Since Turing introduced his test, it has been both highly influential and widely criticised, and has become an important concept in the philosophy of artificial intelligence. Some of its criticisms, such as John Searle's Chinese room, are themselves controversial.
CruiseControl Build loop CruiseControl > Build loop The build loop is designed to run as a daemon process, which periodically checks the revision control system for changes to the codebase, builds if necessary, and publishes a notice regarding the status of the software build.
Mathematical neuroscience Behaviors of networks Mathematical_neuroscience > Major topics > Behaviors of networks In some cases the complex interactions between inhibitory and excitatory neurons can be simplified using mean-field theory, which gives rise to the population model of neural networks. While many neurotheorists prefer such models with reduced complexity, others argue that uncovering structural-functional relations depends on including as much neuronal and network structure as possible. Models of this type are typically built in large simulation platforms like GENESIS or NEURON. There have been some attempts to provide unified methods that bridge and integrate these levels of complexity.
Reaction Progress Kinetic Analysis In situ FT-IR Reaction_Progress_Kinetic_Analysis > Monitoring reaction progress > In situ FT-IR In situ infrared spectroscopy may be used to monitor the course of a reaction, provided a reagent or product shows distinctive absorbance in the IR spectral region. The rate of reactant consumption and/or product formation may be abstracted from the change of absorbance over time (by application of Beers' Law). Even when reactant and product spectra display some degree of overlap, modern instrumentation software is generally able to accurately deconvolute the relative contributions provided there is a dramatic change in the absolute absorbance of the peak of interest over time. In situ IR may be classified as an integral technique as the primary data collected are proportional to concentration vs. time.
Cycles and fixed points Summary Cycles_and_fixed_points In mathematics, the cycles of a permutation π of a finite set S correspond bijectively to the orbits of the subgroup generated by π acting on S. These orbits are subsets of S that can be written as { c1, ..., cn }, such that π(ci) = ci + 1 for i = 1, ..., n − 1, and π(cn) = c1.The corresponding cycle of π is written as ( c1 c2 ... cn ); this expression is not unique since c1 can be chosen to be any element of the orbit. The size n of the orbit is called the length of the corresponding cycle; when n = 1, the single element in the orbit is called a fixed point of the permutation. A permutation is determined by giving an expression for each of its cycles, and one notation for permutations consist of writing such expressions one after another in some order.
Transcription inhibitor Summary Transcription_initiation This may include polyadenylation, capping, and splicing. The RNA may remain in the nucleus or exit the cytoplasm through the nuclear pore complex.If the stretch of DNA is transcribed into an RNA molecule that encodes a protein, the RNA is termed messenger RNA (mRNA); the mRNA, in turn, serves as a template for the protein's synthesis through translation.
Linear congruential generator c ≠ 0 Linear_congruential_generator > Period length > c ≠ 0 The spectral test is one of the most important tests.Note that a power-of-2 modulus shares the problem as described above for c = 0: the low k bits form a generator with modulus 2k and thus repeat with a period of 2k; only the most significant bit achieves the full period. If a pseudorandom number less than r is desired, ⌊rX/m⌋ is a much higher-quality result than X mod r. Unfortunately, most programming languages make the latter much easier to write (X % r), so it is the more commonly used form. The generator is not sensitive to the choice of c, as long as it is relatively prime to the modulus (e.g. if m is a power of 2, then c must be odd), so the value c=1 is commonly chosen.
Walsh diagram Reactivity Walsh_diagram > Reactivity Walsh diagrams in conjunction with molecular orbital theory can also be used as a tool to predict reactivity. By generating a Walsh Diagram and then determining the HOMO/LUMO of that molecule, it can be determined how the molecule is likely to react. In the following example, the Lewis acidity of AH3 molecules such as BH3 and CH3+ is predicted. Six electron AH3 molecules should have a planar conformation.
Linear grammar Expressive power Linear_grammar > Expressive power While regular languages are deterministic, there exist linear languages that are nondeterministic. For example, the language of even-length palindromes on the alphabet of 0 and 1 has the linear grammar S → 0S0 \| 1S1 \| ε. An arbitrary string of this language cannot be parsed without reading all its letters first which means that a pushdown automaton has to try alternative state transitions to accommodate for the different possible lengths of a semi-parsed string.
Mathematical Statistics Probability distributions Mathematical_Statistics > Topics > Probability distributions A probability distribution is a function that assigns a probability to each measurable subset of the possible outcomes of a random experiment, survey, or procedure of statistical inference. Examples are found in experiments whose sample space is non-numerical, where the distribution would be a categorical distribution; experiments whose sample space is encoded by discrete random variables, where the distribution can be specified by a probability mass function; and experiments with sample spaces encoded by continuous random variables, where the distribution can be specified by a probability density function. More complex experiments, such as those involving stochastic processes defined in continuous time, may demand the use of more general probability measures.

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