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Protein Structure Protein folding Amino_acid_residues > Protein folding As it is translated, polypeptides exit the ribosome mostly as a random coil and folds into its native state. The final structure of the protein chain is generally assumed to be determined by its amino acid sequence (Anfinsen's dogma).
Pinnick oxidation Side reactions and scavengers Pinnick_oxidation > Mechanism > Side reactions and scavengers To prevent interference from HOCl, a scavenger is usually added to the reaction to consume the HOCl as it is formed. For example, one can take advantage of the propensity of HOCl to undergo this addition reaction by adding a sacrificial alkene-containing chemical to the reaction mixture. This alternate substrate reacts with the HOCl, preventing the HOCl from undergoing reactions that interfere with the Pinnick reaction itself.
Endocrine bone disease Mechanism Endocrine_bone_disease > Mechanism In fact, Vitamin D is needed for efficient absorption of calcium and therefore proper bone health. Vitamin D is a fat-soluble vitamin, as well, it is unique because it is considered as a hormone; synthesized endogenously in the liver in form of Cholecalciferol. The endogenous inactive form of Vitamin D is Cholecalciferol or Vitamin D3 which is converted to active form of Vitamin D–Calcitriol also known as 1, 25-Dihydroxycholecalciferol in the Kidney upon exposure to UV ray of sun light.
Ternary search tree Running time Ternary_search_tree > Running time Running times for ternary search trees are similar to binary search trees, in that they typically run in logarithmic time, but can run in linear time in the degenerate (worst) case. Further, the size of the strings must also be kept in mind when considering runtime. For example, in the search path for a string of length k, there will be k traversals down middle children in the tree, as well as a logarithmic number of traversals down left and right children in the tree. Thus, in a ternary search tree on a small number of very large strings the lengths of the strings can dominate the runtime.Time complexities for ternary search tree operations:
Solar lamp Benefits Solar_lamp > Benefits Lack of lighting equates to continued poverty felt around the world. In solar energy lamp it converts light energy into electrical energy, i.e. It is convenient to our daily life. Solar energy output is limited by weather and can be less effective if it is cloudy, wet, or winter.Households switching to solar lamps from kerosene lamps also gain from health risk associated with kerosene emissions.
BolA-like protein family Summary BolA-like_protein_family In molecular biology, the BolA-like protein family consists of the morpho-protein BolA from Escherichia coli, the Fra2 protein from Saccharomyces cerevisiae, and various homologs. The BolA protein is a DNA-binding regulator; the Fra2 protein is an iron sulfur cluster protein that binds Grx3/4 and is involved in regulating iron levels .In E. coli, over-expression of this protein causes round morphology and may be involved in switching the cell between elongation and septation systems during cell division. The expression of BolA is growth rate regulated and is induced during the transition into the stationary phase.
Unifying theories in mathematics Category theory as a rival Unifying_theories_in_mathematics > Category theory as a rival (For example, are all equilateral triangles the same, or does size matter?) Saunders Mac Lane proposed that any concept with enough 'ubiquity' (occurring in various branches of mathematics) deserved isolating and studying in its own right. Category theory is arguably better adapted to that end than any other current approach. The disadvantages of relying on so-called abstract nonsense are a certain blandness and abstraction in the sense of breaking away from the roots in concrete problems. Nevertheless, the methods of category theory have steadily advanced in acceptance, in numerous areas (from D-modules to categorical logic).
PlayStation Eye Camera Applications PlayStation_Eye_Camera > Features > Applications According to Sony; the facial technology can identify features such as eyes, mouth, eyebrows, nose, and eyeglasses; read the shape of the mouth and detect a smile; determine the position and orientation of the subject's head; and estimate the age and gender of the face.In addition to gaming-oriented uses, Sony has stated that the PlayStation Eye will also feature applications for tasks such as interactive communication and content creation (e.g. movie-making and video blogging). An AV Chat feature allows for audio-visual chat with anyone on a user's PlayStation Network friends list (up to six at once). Additional free content and activities are planned for release via the PlayStation Network.
Bonding in solids Molecular to network covalent Bonding_in_solids > Solids of intermediate kinds > Molecular to network covalent Intermediate kinds of bonding: A solid with extensive hydrogen bonding will be considered a molecular solid, yet strong hydrogen bonds can have a significant degree of covalent character. As noted above, covalent and ionic bonds form a continuum between shared and transferred electrons; covalent and weak bonds form a continuum between shared and unshared electrons. In addition, molecules can be polar, or have polar groups, and the resulting regions of positive and negative charge can interact to produce electrostatic bonding resembling that in ionic solids.
Bartlett's theorem Summary Bartlett's_theorem In queueing theory, Bartlett's theorem gives the distribution of the number of customers in a given part of a system at a fixed time.
Reading path Linear reading path Reading_path > Linear reading path An example of a linear reading path might be a textbook, with pictures, or paragraphs where the reader is led to assume cause-and-effect sequences, for example. Speech is also a linear path because the path is more "set". according to Kress.
Marine prokaryotes Trophic mode Marine_prokaryotes > Trophic mode This enables marine prokaryotes to thrive as extremophiles in harsh environments as cold as the ice surface of Antarctica, studied in cryobiology, as hot as undersea hydrothermal vents, or in high saline conditions as (halophiles). Some marine prokaryotes live symbiotically in or on the bodies of other marine organisms. Phototrophy is a particularly significant marker that should always play a primary role in bacterial classification.
End-to-end connectivity Limitations End_to_end_principle > Limitations The most important limitation of the end-to-end principle is that its basic premise, placing functions in the application endpoints rather than in the intermediary nodes, is not trivial to implement. An example of the limitations of the end-to-end principle exists in mobile devices, for instance with mobile IPv6. Pushing service-specific complexity to the endpoints can cause issues with mobile devices if the device has unreliable access to network channels.Further problems can be seen with a decrease in network transparency from the addition of network address translation (NAT), which IPv4 relies on to combat address exhaustion. With the introduction of IPv6, users once again have unique identifiers, allowing for true end-to-end connectivity.
Chest pain Outpatient care Chest_pain > Management > Outpatient care However, treatment with proton pump inhibitors has been shown to be no better than placebo in persons with noncardiac chest pain not caused by gastroesophageal reflux disease. For musculoskeletal causes of chest pain, manipulation therapy or chiropractic therapy, acupuncture, or a recommendation for increased exercise are often used as treatment. Studies have shown conflicting results on the efficacy of these treatments. A combination therapy of nonsteroidal anti-inflammatory drugs and manipulation therapy with at-home exercises has been shown to be most effective in treatment of musculoskeletal chest pain.
Algorithmic transparency Summary Algorithmic_transparency Algorithmic transparency is the principle that the factors that influence the decisions made by algorithms should be visible, or transparent, to the people who use, regulate, and are affected by systems that employ those algorithms. Although the phrase was coined in 2016 by Nicholas Diakopoulos and Michael Koliska about the role of algorithms in deciding the content of digital journalism services, the underlying principle dates back to the 1970s and the rise of automated systems for scoring consumer credit. The phrases "algorithmic transparency" and "algorithmic accountability" are sometimes used interchangeably – especially since they were coined by the same people – but they have subtly different meanings. Specifically, "algorithmic transparency" states that the inputs to the algorithm and the algorithm's use itself must be known, but they need not be fair.
Adrien-Marie Legendre Mathematical work Adrien-Marie_Legendre > Mathematical work He also did pioneering work on the distribution of primes, and on the application of analysis to number theory. His 1798 conjecture of the prime number theorem was rigorously proved by Hadamard and de la Vallée-Poussin in 1896. Legendre did an impressive amount of work on elliptic functions, including the classification of elliptic integrals, but it took Abel's stroke of genius to study the inverses of Jacobi's functions and solve the problem completely.
Hard-disk failure Modes of failure Adaptation_data > Signs of drive failure > Modes of failure Circuit failure: components of the electronic circuitry may fail making the drive inoperable, often due to electrostatic discharge or user error. Bearing and motor failure: electric motors may fail or burn out, and bearings may wear enough to prevent proper operation. Since modern drives use fluid dynamic bearings, this is a relatively uncommon reason for modern hard drive failure. Miscellaneous mechanical failures: parts, particularly moving parts, of any mechanism can break or fail, preventing normal operation, with possible further damage caused by fragments.
Control (management) Organizational and operational control Control_(management) > Classifications > Organizational and operational control It is appropriate to investigate areas that have been troublesome before or areas where some measure of performance can be quickly identified. For example, if an organization's output backlog builds rapidly, it is logical to check first to see if the problem is due to such readily obtainable measures as increased demand or to a drop in available man hours. When a more detailed analysis is necessary, a systematic procedure should be followed.In contrast to organizational control, operational control serves to regulate the day-to-day output relative to schedules, specifications, and costs.
Geometric sum Euclid of Alexandria (c.300 BC) Geometric_series > History > Euclid of Alexandria (c.300 BC) And the book's popularity lasted a long time: as stated in the cited introduction to an English translation, Elements of Geometry "has the distinction of being the world's oldest continuously used mathematical textbook." So being very terse was being very practical. The proof of Proposition 35 in Book IX could have been even more compact if Euclid could have somehow avoided explicitly equating lengths of specific line segments from different terms in the series.
Induced homomorphism (quotient group) Other examples Induced_homomorphism > Other examples Likewise there are induced homomorphisms of higher homotopy groups and homology groups. Any homology theory comes with induced homomorphisms. For instance, simplicial homology, singular homology, and Borel–Moore homology all have induced homomorphisms (IV.1.3, pp. 240–241) Similarly, any cohomology comes induced homomorphisms, though in the opposite direction (from a group associated with Y to a group associated with X).
Oncogenomics History Genetics_of_cancer > History Cancer is also a major focus of epigenetic studies. Access to whole cancer genome sequencing is important to cancer (or cancer genome) research because: Mutations are the immediate cause of cancer and define the tumor phenotype. Access to cancerous and normal tissue samples from the same patient and the fact that most cancer mutations represent somatic events, allow the identification of cancer-specific mutations. Cancer mutations are cumulative and sometimes are related to disease stage. Metastasis and drug resistance are distinguishable.Access to methylation profiling is important to cancer research because: Epi-drivers, along with Mut-drivers, can act as immediate causes of cancers Cancer epimutations are cumulative and sometimes related to disease stage
Cycle graph (algebra) Cycles Cycle_graph_(group) > Cycles Cycles can overlap, or they can have no element in common but the identity. The cycle graph displays each interesting cycle as a polygon. If a generates a cycle of order 6 (or, more shortly, has order 6), then a6 = e. Then the set of powers of a2, {a2, a4, e} is a cycle, but this is really no new information. Similarly, a5 generates the same cycle as a itself.
Infrared photography Summary Infrared_photography The effect is named after the infrared photography pioneer Robert W. Wood, and not after the material wood, which does not strongly reflect infrared. The other attributes of infrared photographs include very dark skies and penetration of atmospheric haze, caused by reduced Rayleigh scattering and Mie scattering, respectively, compared to visible light. The dark skies, in turn, result in less infrared light in shadows and dark reflections of those skies from water, and clouds will stand out strongly. These wavelengths also penetrate a few millimeters into skin and give a milky look to portraits, although eyes often look black.
Transistor laser Construction of transistor Transistor_laser > Construction of transistor Light bounces back and forth between reflective walls inside the 2.2 micrometer wide emitter that acts as a resonant cavity. Finally, light is emitted as a laser.The device was initially constructed out of layers of indium gallium phosphide, gallium arsenide, and indium gallium arsenide, which prevented the device from running without being cooled with liquid nitrogen. Current materials allow for operation at 25 °C and continuous wave operation (continuously emitting light) at 3 GHz. The transistor laser can produce laser output without any resonance peak in the frequency response. It also does not suffer from unwanted self-resonance that results in errors in transmitted information that would necessitate complicated external circuitry to rectify.
Saccharide transporter Summary Saccharide_transporter The bacterial phosphoenolpyruvate: sugar phosphotransferase system (PTS) is a multi-protein system involved in the regulation of a variety of metabolic and transcriptional processes. The PTS catalyzes the phosphorylation of incoming sugar substrates concomitant with their translocation across the cell membrane. The general mechanism of the PTS is the following: a phosphoryl group from phosphoenolpyruvate (PEP) is transferred to enzyme-I (EI) of PTS which in turn transfers it to a phosphoryl carrier protein (HPr).
Computerized adaptive testing Pass-fail Computerized_adaptive_testing > Other issues > Pass-fail For examinees with true scores very close to the passing score, computerized classification tests will result in long tests while those with true scores far above or below the passing score will have shortest exams. For example, a new termination criterion and scoring algorithm must be applied that classifies the examinee into a category rather than providing a point estimate of ability.
Security of automated teller machines Authentication and data integrity Security_of_automated_teller_machines > Security measures of ATMs > PIN validation schemes for local transactions > Authentication and data integrity The personal verification process begins with the user's supply of personal verification information. This information includes a PIN and the provided customer's information which is recorded on the bank account. In cases where there is a storage of a cryptographic key on the bank card, it is called a personal key (PK).
Spontaneously broken Other examples Spontaneously_broken_symmetry > Examples > Other examples But after buckling, it looks different, and asymmetric. Nevertheless, features of the cylindrical symmetry are still there: ignoring friction, it would take no force to freely spin the rod around, displacing the ground state in time, and amounting to an oscillation of vanishing frequency, unlike the radial oscillations in the direction of the buckle. This spinning mode is effectively the requisite Nambu–Goldstone boson.
Visual spatial attention Gradient model Visual_spatial_attention > Distribution of spatial attention > Gradient model There was no evidence of a gradient effect, as the faster responses were when the cue and target were in the same hemifield and slower responses when they were in different hemifields. The boxes played an important role in attention as a later experiment, used the boxes and consequently found a gradient pattern. Therefore, it is considered that the size of the gradient can adjust according to the circumstances. A broader gradient may be adopted when there is an empty display, as attention can spread and is only restricted by hemifield borders.
Descriptional Complexity of Formal Systems History of the workshop Descriptional_Complexity_of_Formal_Systems > History of the workshop Chairs of the Steering Committee of the DCFS workshop series: Basic information on each DCFS event, as well as on its precursors, DCAGRS and FSDR, is included in the following table.
PeerTube Technology PeerTube > Technology PeerTube uses WebTorrent technology. Each server hosts a torrent tracker and each web browser viewing a video also shares it. This allows to share the load between the server itself and the clients as well as the bandwidth used through P2P technology. The system works via a federation of instances run by independent entities.
Management control Classifications Control_(management) > Classifications Control may be grouped according to three general classifications: the nature of the information flow designed into the system (open- or closed-loop control) the kind of components included in the design (man or machine control systems) the relationship of control to the decision process (organizational or operational control).
Solvable by radicals Pre-history Galois_Theory > History > Pre-history He was the first who discovered the rules for summing the powers of the roots of any equation. In this vein, the discriminant is a symmetric function in the roots that reflects properties of the roots – it is zero if and only if the polynomial has a multiple root, and for quadratic and cubic polynomials it is positive if and only if all roots are real and distinct, and negative if and only if there is a pair of distinct complex conjugate roots. See Discriminant:Nature of the roots for details.
Continuous and progressive aspects Spanish Continuous_and_progressive_aspects > Continuous and progressive in various languages > Spanish In Spanish, the continuous is constructed much as in English, using a conjugated form of estar (to be) plus the gerundio (gerund/gerundive/adverbial participle) of the main verb; for example, estar haciendo means to be doing (haciendo being the gerundio of hacer, to do). Like English, Spanish also has a few related constructions with similar structures and related meanings; for example, seguir haciendo means to keep doing (seguir being to continue). Conjugations of the Present Progressive in Spanish:
Global symmetry Mathematics of physical symmetry Internal_symmetries > Mathematics of physical symmetry The transformations describing physical symmetries typically form a mathematical group. Group theory is an important area of mathematics for physicists. Continuous symmetries are specified mathematically by continuous groups (called Lie groups).
Potassium carbide Interstitial / Metallic carbides Potassium_carbide > Interstitial / Metallic carbides When the metal atoms are hexagonal close-packed, (hcp), as the octahedral interstices lie directly opposite each other on either side of the layer of metal atoms, filling only one of these with carbon achieves 2:1 stoichiometry with the CdI2 structure.The following table shows structures of the metals and their carbides. (N.B. the body centered cubic structure adopted by vanadium, niobium, tantalum, chromium, molybdenum and tungsten is not a close-packed lattice.)
Linearly independent vectors Alternative method using determinants Linearly_independent > Evaluating linear independence > Alternative method using determinants Since the determinant is non-zero, the vectors ( 1 , 1 ) {\displaystyle (1,1)} and ( − 3 , 2 ) {\displaystyle (-3,2)} are linearly independent. Otherwise, suppose we have m {\displaystyle m} vectors of n {\displaystyle n} coordinates, with m < n . {\displaystyle m n {\displaystyle m>n} , then it is a theorem that the vectors must be linearly dependent.) This fact is valuable for theory; in practical calculations more efficient methods are available.
Deep convolutional neural network Building blocks Pooling_(neural_networks) > Building blocks A CNN architecture is formed by a stack of distinct layers that transform the input volume into an output volume (e.g. holding the class scores) through a differentiable function. A few distinct types of layers are commonly used. These are further discussed below.
Diabetes management Complexities Diabetes_management > Overview > Complexities The main complexities stem from the nature of the feedback loop of the glucose cycle, which is sought to be regulated: The glucose cycle is a system which is affected by two factors: entry of glucose into the bloodstream and also blood levels of insulin to control its transport out of the bloodstream As a system, it is sensitive to diet and exercise It is affected by the need for user anticipation due to the complicating effects of time delays between any activity and the respective impact on the glucose system Management is highly intrusive, and compliance is an issue, since it relies upon user lifestyle change and often upon regular sampling and measuring of blood glucose levels, multiple times a day in many cases It changes as people grow and develop It is highly individualAs diabetes is a prime risk factor for cardiovascular disease, controlling other risk factors which may give rise to secondary conditions, as well as the diabetes itself, is one of the facets of diabetes management. Checking cholesterol, LDL, HDL and triglyceride levels may indicate hyperlipoproteinemia, which may warrant treatment with hypolipidemic drugs. Checking the blood pressure and keeping it within strict limits (using diet and antihypertensive treatment) protects against the retinal, renal and cardiovascular complications of diabetes. Regular follow-up by a podiatrist or other foot health specialists is encouraged to prevent the development of diabetic foot. Annual eye exams are suggested to monitor for progression of diabetic retinopathy.
Testosterone and the cardiovascular system Replacement therapy Testosterone_and_the_cardiovascular_system > Replacement therapy Physiological testosterone is crucial for normal functionality in men. Long-term administration of physiological testosterone in mouse models has shown to be atheroprotective by increasing the HDL portion of cholesterol (the anti-atherosclerotic cholesterol). The beneficial action of testosterone in elevating the HDL fraction can be attributed to its conversion via aromatase activity in adipose tissue into 17-beta estradiol and its subsequent activation of estrogen alpha-receptors; thus, more testosterone leads to greater conversion into estrogen and thus a healthier lipid profile. This understanding has been determined in several studies, although results of these studies are contradictory.Testosterone replacement therapy in men diagnosed with pre-existing heart disease has been related to an increased risk of myocardial infarction.
Digital Control Bus Implementation Digital_Control_Bus > Implementation Following information comes from the Roland JUNO-60 Service Notes, First Edition, page 17–19.
Netsukuku Operation Netsukuku > Operation This offers a set of advantages main documentation. The protocol relies on the fact that the nodes are not mobile and that the network structure does not change quickly, as several minutes may be required before a change in the network is propagated. However, a node that joins the network is immediately able to communicate using the routes of its neighbors.
Computer programs Imperative languages Computer_programs > Programming paradigms and languages > Imperative languages Imperative languages specify a sequential algorithm using declarations, expressions, and statements: A declaration introduces a variable name to the computer program and assigns it to a datatype – for example: var x: integer; An expression yields a value – for example: 2 + 2 yields 4 A statement might assign an expression to a variable or use the value of a variable to alter the program's control flow – for example: x := 2 + 2; if x = 4 then do_something();
Unconscious inference The Helmholtz machine Unconscious_inference > Influences in current computer science and psychology > The Helmholtz machine Work in computer science has made use of Helmholtz's ideas of unconscious inference by suggesting the cortex contains a generative model of the world. They develop a statistical method for discovering the structure inherent in a set of patterns: Following Helmholtz, we view the human perceptual system as a statistical inference engine whose function is to infer the probable causes of sensory input. We show that a device of this kind can learn how to perform these inferences without requiring a teacher to label each sensory input vector with its underlying causes.
DNA polymerase II Confirmed DNA_polymerase_II > Function > Confirmed While DNA Pol II is not a major factor in chromosome replication, it has other roles to fill. DNA Pol II does participate in DNA replication. While it might not be as fast as DNA Pol III, it has some abilities that make it an effective enzyme.
Closed system (thermodynamics) In chemistry Closed_system_(thermodynamics) > In chemistry In chemistry, a closed system is where no reactants or products can escape, only heat can be exchanged freely (e.g. an ice cooler). A closed system can be used when conducting chemical experiments where temperature is not a factor (i.e. reaching thermal equilibrium).
Einstein's thought experiments Impossibility of faster-than-light signaling Einstein's_thought_experiments > Special relativity > Impossibility of faster-than-light signaling In 1907, Einstein noted that from the composition law for velocities, one could deduce that there cannot exist an effect that allows faster-than-light signaling.Einstein imagined a strip of material that allows propagation of signals at the faster-than-light speed of W {\displaystyle W} (as viewed from the material strip). Imagine two observers, A and B, standing on the x-axis and separated by the distance L {\displaystyle L} . They stand next to the material strip, which is not at rest, but rather is moving in the negative x-direction with speed v {\displaystyle v} . A uses the strip to send a signal to B. From the velocity composition formula, the signal propagates from A to B with speed ( W − v ) / ( 1 − ( W v / c 2 ) ) {\displaystyle {(W-v)/(1-(Wv/c^{2}))}} .
Energy industry Summary Energy_industry The energy industry is the totality of all of the industries involved in the production and sale of energy, including fuel extraction, manufacturing, refining and distribution. Modern society consumes large amounts of fuel, and the energy industry is a crucial part of the infrastructure and maintenance of society in almost all countries. In particular, the energy industry comprises: the fossil fuel industries, which include petroleum industries (oil companies, petroleum refiners, fuel transport and end-user sales at gas stations) coal industries (extraction and processing) and the natural gas industries (natural gas extraction, and coal gas manufacture, as well as distribution and sales); the electrical power industry, including electricity generation, electric power distribution and sales; the nuclear power industry; the renewable energy industry, comprising alternative energy and sustainable energy companies, including those involved in hydroelectric power, wind power, and solar power generation, and the manufacture, distribution and sale of alternative fuels; and, traditional energy industry based on the collection and distribution of firewood, the use of which, for cooking and heating, is particularly common in poorer countries.
Twelvefold way Injective functions from N to X, up to a permutation of X Twelvefold_way > Formulas > Details of the different cases > Injective functions from N to X, up to a permutation of X In this case we consider sequences of n distinct elements from X, but identify those obtained from one another by applying to each element a permutation of X. It is easy to see that two different such sequences can always be identified: the permutation must map term i of the first sequence to term i of the second sequence, and since no value occurs twice in either sequence these requirements do not contradict each other; it remains to map the elements not occurring in the first sequence bijectively to those not occurring in the second sequence in an arbitrary way. The only fact that makes the result depend on n and x at all is that the existence of any such sequences to begin with requires n ≤ x, by the pigeonhole principle. The number is therefore expressed as {\displaystyle } , using the Iverson bracket.
Evolutionary immunology Summary Evolutionary_immunology Immunology is a branch of biology and medicine that covers the study of immune systems in all organisms. Immunology charts, measures, and contextualizes the physiological functioning of the immune system in states of both health and diseases; malfunctions of the immune system in immunological disorders (such as autoimmune diseases, hypersensitivities, immune deficiency, and transplant rejection); and the physical, chemical, and physiological characteristics of the components of the immune system in vitro, in situ, and in vivo. Immunology has applications in numerous disciplines of medicine, particularly in the fields of organ transplantation, oncology, rheumatology, virology, bacteriology, parasitology, psychiatry, and dermatology. The term was coined by Russian biologist Ilya Ilyich Mechnikov, who advanced studies on immunology and received the Nobel Prize for his work in 1908 with Paul Ehrlich "in recognition of their work on immunity".
DNA-dependent ATPase Molecular biology DNA-dependent_ATPase > Molecular biology Dda is involved in the initiation of T4 DNA replication and DNA recombination.
Thermal cycler Summary Thermal_cyclers The thermal cycler (also known as a thermocycler, PCR machine or DNA amplifier) is a laboratory apparatus most commonly used to amplify segments of DNA via the polymerase chain reaction (PCR). Thermal cyclers may also be used in laboratories to facilitate other temperature-sensitive reactions, including restriction enzyme digestion or rapid diagnostics. The device has a thermal block with holes where tubes holding the reaction mixtures can be inserted. The cycler then raises and lowers the temperature of the block in discrete, pre-programmed steps.
Privacy for research participants Privacy attacks Privacy_for_research_participants > Information privacy > Privacy attacks Ideally, this means that the dataset alone could not be used to identify a participant.In some cases, the researchers simply misjudge the information in a de-identified dataset and actually it is identifying, or perhaps the advent of new technology makes the data identifying. In other cases, the published de-identified data can be cross-referenced with other data sets, and by finding matches between an identified dataset and the de-identified data set, participants in the de-identified set may be revealed. This is particularly the case with medical research data because traditional data anonymization techniques designed for numerical data are not as effective for the nonnumerical data contained in medical data, such as rare diagnoses and personalized treatments. Thus, in cases like medical research data that contain unique nonnumerical data, only removing identifying numerical features, such as age and social security number, may not be enough to mitigate privacy attacks.
Canonical angular momentum Newton's derivation Introduction_to_angular_momentum > History > The Law of Areas > Newton's derivation When the object arrives at B, it receives an impulse directed toward point S. The impulse gives it a small added velocity toward S, such that if this were its only velocity, it would move from B to V during the second interval. By the rules of velocity composition, these two velocities add, and point C is found by construction of parallelogram BcCV. Thus the object's path is deflected by the impulse so that it arrives at point C at the end of the second interval.
Splice site mutation Summary Splice_site_mutation Introns are supposed to be removed, while the exons are expressed. The mutation must occur at the specific site at which intron splicing occurs: within non-coding sites in a gene, directly next to the location of the exon. The mutation can be an insertion, deletion, frameshift, etc. The splicing process itself is controlled by the given sequences, known as splice-donor and splice-acceptor sequences, which surround each exon.
Absolutely convergent Relation to convergence Absolute_convergence > Relation to convergence If G {\displaystyle G} is complete with respect to the metric d , {\displaystyle d,} then every absolutely convergent series is convergent. The proof is the same as for complex-valued series: use the completeness to derive the Cauchy criterion for convergence—a series is convergent if and only if its tails can be made arbitrarily small in norm—and apply the triangle inequality. In particular, for series with values in any Banach space, absolute convergence implies convergence. The converse is also true: if absolute convergence implies convergence in a normed space, then the space is a Banach space.
Fluvoxamine Pharmacology Fluvoxamine > Pharmacology Fluvoxamine is a potent selective serotonin reuptake inhibitor with around 100-fold affinity for the serotonin transporter over the norepinephrine transporter. It has negligible affinity for the dopamine transporter or any other site, with the sole exception of the σ1 receptor. It behaves as a potent agonist at this receptor and has the highest affinity (36 nM) of any SSRI for doing so. This may contribute to its antidepressant and anxiolytic effects and may also afford it some efficacy in treating the cognitive symptoms of depression. Unlike some other SSRI, fluvoxamine's metabolites are pharmacologically neutral.
Poly-Bernoulli number Summary Poly-Bernoulli_number Moreover, the Generalization of Poly-Bernoulli numbers with a,b,c parameters defined as follows L i k ( 1 − ( a b ) − x ) b x − a − x c x t = ∑ n = 0 ∞ B n ( k ) ( t ; a , b , c ) x n n ! {\displaystyle {Li_{k}(1-(ab)^{-x}) \over b^{x}-a^{-x}}c^{xt}=\sum _{n=0}^{\infty }B_{n}^{(k)}(t;a,b,c){x^{n} \over n!}}
Non-homologous isofunctional enzymes Origins Non-homologous_isofunctional_enzymes > Origins A possible mechanism for the formation and evolution of these enzymes is recruitment of existing enzymes that gain new functions by a modification in substrate specificity (specifically at or near the active site) or modification of the existing catalytic mechanism.
Mathematical formulation of quantum mechanics The "new quantum theory" Mathematical_foundation_of_quantum_field_theory > History of the formalism > The "new quantum theory" In his above-mentioned account, he introduced the bra–ket notation, together with an abstract formulation in terms of the Hilbert space used in functional analysis; he showed that Schrödinger's and Heisenberg's approaches were two different representations of the same theory, and found a third, most general one, which represented the dynamics of the system. His work was particularly fruitful in many types of generalizations of the field. The first complete mathematical formulation of this approach, known as the Dirac–von Neumann axioms, is generally credited to John von Neumann's 1932 book Mathematical Foundations of Quantum Mechanics, although Hermann Weyl had already referred to Hilbert spaces (which he called unitary spaces) in his 1927 classic paper and book.
Michael Faraday Summary Michael_Faraday Faraday ultimately became the first and foremost Fullerian Professor of Chemistry at the Royal Institution, a lifetime position. Faraday was an experimentalist who conveyed his ideas in clear and simple language; his mathematical abilities, however, did not extend as far as trigonometry and were limited to the simplest algebra. James Clerk Maxwell took the work of Faraday and others and summarized it in a set of equations which is accepted as the basis of all modern theories of electromagnetic phenomena.
Ramsey–Cass–Koopmans model Model setup Ramsey–Cass–Koopmans_model > Mathematical description > Model setup In the usual setup, time is continuous starting, for simplicity, at t = 0 {\displaystyle t=0} and continuing forever. By assumption, the only productive factors are capital K {\displaystyle K} and labour L {\displaystyle L} , both required to be nonnegative. The labour force, which makes up the entire population, is assumed to grow at a constant rate n {\displaystyle n} , i.e. L ˙ = d L d t = n L {\displaystyle {\dot {L}}={\tfrac {\mathrm {d} L}{\mathrm {d} t}}=nL} , implying that L = L 0 e n t {\displaystyle L=L_{0}e^{nt}} with initial level L 0 > 0 {\displaystyle L_{0}>0} at t = 0 {\displaystyle t=0} . Finally, let Y {\displaystyle Y} denote aggregate production, and C {\displaystyle C} denote aggregate consumption.
Circular dichroism spectroscopy Extrinsic effects on circular dichroism Circular_dichroism_spectroscopy > Physical principles > Interaction of circularly polarized light with matter > Extrinsic effects on circular dichroism In many practical applications of circular dichroism (CD), as discussed below, the measured CD is not simply an intrinsic property of the molecule, but rather depends on the molecular conformation. In such a case the CD may also be a function of temperature, concentration, and the chemical environment, including solvents. In this case the reported CD value must also specify these other relevant factors in order to be meaningful. In ordered structures lacking two-fold rotational symmetry, optical activity, including differential transmission (and reflection) of circularly polarized waves also depends on the propagation direction through the material. In this case, so-called extrinsic 3d chirality is associated with the mutual orientation of light beam and structure.
Service-oriented architectures Implementation approaches Service-oriented_architectures > Implementation approaches One example is SOAP, which has gained broad industry acceptance after the recommendation of Version 1.2 from the W3C (World Wide Web Consortium) in 2003. These standards (also referred to as web service specifications) also provide greater interoperability and some protection from lock-in to proprietary vendor software. One can, however, also implement SOA using any other service-based technology, such as Jini, CORBA, Internet Communications Engine, REST, or gRPC.
Trimethylenemethane complexes Summary Trimethylenemethane_complexes In 1956, Longuet-Higgins and Orgel predicted the existence of transition-metal cyclobutadiene complexes, in which the degenerate eg orbital of cyclobutadiene has the correct symmetry for π interaction with the dxz and dyz orbitals of the proper metal. The compound was synthesized three years after the prediction and it serves as a beautiful case of theory before experiment. This successful attempt opens the door for the formation of novel compounds containing other organic ligands which in their free state are highly reactive molecules. Of all those reactive molecules, trimethylenemethane (TMM) has the most natural derivation from the cyclobutadiene complexes and in 1966, Emerson and co-workers reported the first trimethylenemethane (TMM) transition metal complex, (CO)3FeC(CH2)3, which became the starting point of the legends of trimethylenemethane complexes. Some good reviews on this aspect could be served as further resources for this topic.
Nancey Murphy Selected journal articles Nancey_Murphy > Selected journal articles "The Problem of Mental Causation: How Does Reason Get Its Grip on the Brain?" Science and Christian Belief, October. 1999.
Selective serotonin reuptake inhibitors Versus TCAs Selective_serotonin_reuptake_inhibitor > Mechanism of action > Versus TCAs Tricyclic antidepressants also have a higher risk of serious cardiovascular side effects, which SSRIs lack. SSRIs act on signal pathways such as cyclic adenosine monophosphate (cAMP) on the postsynaptic neuronal cell, which leads to the release of brain-derived neurotrophic factor (BDNF). BDNF enhances the growth and survival of cortical neurons and synapses.
Edge router Applications Access_router > Applications A router may have interfaces for multiple types of physical layer connections, such as copper cables, fiber optic, or wireless transmission. It can also support multiple network layer transmission standards. Each network interface is used to enable data packets to be forwarded from one transmission system to another. Routers may also be used to connect two or more logical groups of computer devices known as subnets, each with a unique network prefix.
CPU instruction Summary Instruction_overlapping Machine code is a strictly numerical language, and is the lowest-level interface to the CPU intended for a programmer. Assembly language provides a direct mapping between the numerical machine code and a human-readable version where numerical opcodes and operands are replaced by readable strings (e.g. 0x90 is the NOP instruction on x86). While it is possible to write programs directly in machine code, managing individual bits and calculating numerical addresses and constants manually is tedious and error-prone.
Dynamical dimensional reduction Evidence for dimensional reduction Dynamical_dimensional_reduction > Evidence for dimensional reduction The spectral dimension is a measure of the effective dimension of a manifold at different resolution scales. Early numerical simulations within the causal dynamical triangulation (CDT) approach to quantum gravity found a spectral dimension of 4.02 ± 0.10 at large distances and 1.80 ± 0.25 at small distances. This result created significant interest in dimensional reduction within the quantum gravity community. A more recent study of the same point in the parameter space of CDT found consistent results, namely 4.05 ± 0.17 at large distances and 1.97 ± 0.27 at small distances.Currently, there is no consensus on the correct theoretical explanation for the mechanism of dimensional reduction.
Computer Memory Virtual memory Off-chip_memory > Management > Virtual memory Virtual memory is a system where physical memory is managed by the operating system typically with assistance from a memory management unit. It allows multiple types of memory to be used. For example, some data can be stored in RAM while other data is stored on a hard drive (e.g. in a swapfile), functioning as an extension of the cache hierarchy. This offers several advantages.
Charles Babbage Metrology programme Charles_Babbage > Later life > Metrology programme A project announced by Babbage was to tabulate all physical constants (referred to as "constants of nature", a phrase in itself a neologism), and then to compile an encyclopaedic work of numerical information. He was a pioneer in the field of "absolute measurement". His ideas followed on from those of Johann Christian Poggendorff, and were mentioned to Brewster in 1832.
Error propagation Summary Error_propagation In statistics, propagation of uncertainty (or propagation of error) is the effect of variables' uncertainties (or errors, more specifically random errors) on the uncertainty of a function based on them. When the variables are the values of experimental measurements they have uncertainties due to measurement limitations (e.g., instrument precision) which propagate due to the combination of variables in the function. The uncertainty u can be expressed in a number of ways. It may be defined by the absolute error Δx.
User-in-the-loop Summary User-in-the-loop Both elements of smart decision-making and observed values can help towards improving the bigger objective. The input values are meant to encourage/discourage human users to behave in certain ways that improve the overall performance of the system.
Graft polymer Summary High_Impact_Polystyrene In polymer chemistry, graft polymers are segmented copolymers with a linear backbone of one composite and randomly distributed branches of another composite. The picture labeled "graft polymer" shows how grafted chains of species B are covalently bonded to polymer species A. Although the side chains are structurally distinct from the main chain, the individual grafted chains may be homopolymers or copolymers. Graft polymers have been synthesized for many decades and are especially used as impact resistant materials, thermoplastic elastomers, compatibilizers, or emulsifiers for the preparation of stable blends or alloys. One of the better-known examples of a graft polymer is a component used in high impact polystyrene, consisting of a polystyrene backbone with polybutadiene grafted chains.
DNA transposon Summary DNA_transposon They can make up a significant portion of an organism's genome, particularly in eukaryotes. In prokaryotes, TE's can facilitate the horizontal transfer of antibiotic resistance or other genes associated with virulence. After replicating and propagating in a host, all transposon copies become inactivated and are lost unless the transposon passes to a genome by starting a new life cycle with horizontal transfer.
Hypothalamic–pituitary–adrenal axis Function Hypothalamic-pituitary-adrenal_axis > Function The HPA axis integrates physical and psychosocial influences in order to allow an organism to adapt effectively to its environment, use resources, and optimize survival.Anatomical connections between brain areas such as the amygdala, hippocampus, prefrontal cortex and hypothalamus facilitate activation of the HPA axis. Sensory information arriving at the lateral aspect of the amygdala is processed and conveyed to the amygdala's central nucleus, which then projects out to several parts of the brain involved in responses to fear. At the hypothalamus, fear-signaling impulses activate both the sympathetic nervous system and the modulating systems of the HPA axis.
Compact Muon Solenoid Trigger system Compact_Muon_Solenoid > Collecting and collating the data > Trigger system To have a good chance of producing a rare particle, such as a Higgs boson, a very large number of collisions is required. Most collision events in the detector are "soft" and do not produce interesting effects. The amount of raw data from each crossing is approximately 1 megabyte, which at the 40 MHz crossing rate would result in 40 terabytes of data a second, an amount that the experiment cannot hope to store, let alone process properly. The full trigger system reduces the rate of interesting events down to a manageable 1,000 per second.
Kepler-283c Mass, radius and temperature Kepler-283c > Characteristics > Mass, radius and temperature It has a surface equilibrium temperature of 238.5 K (−34.6 °C; −30.4 °F). Its radius is 1.82 R🜨. Its orbit is circular with an eccentricity of 0.
Database Database management system Data_base_management_system > Database management system The functionality provided by a DBMS can vary enormously. The core functionality is the storage, retrieval and update of data. Codd proposed the following functions and services a fully-fledged general purpose DBMS should provide: Data storage, retrieval and update User accessible catalog or data dictionary describing the metadata Support for transactions and concurrency Facilities for recovering the database should it become damaged Support for authorization of access and update of data Access support from remote locations Enforcing constraints to ensure data in the database abides by certain rulesIt is also generally to be expected the DBMS will provide a set of utilities for such purposes as may be necessary to administer the database effectively, including import, export, monitoring, defragmentation and analysis utilities.
Portal venous system In humans Portal_circulation > In humans It is anterior to the omental foramen and posterior to both the bile duct, which is slightly to the right, and the hepatic artery proper, which is slightly to the left. On approaching the liver, the portal vein divides into right and left branches which enter the liver parenchyma. It gives off the right and left gastric veins, the cystic vein and the para-umbilical veins as tributaries.
SPIKES Summary SPIKES P: perception, i.e. assessing the patient's perception of the situation→ Begin by asking the patient what they believe is going on. This not only allows you to find out what they know about the situation, but also engages the patient. It allows for them to realize what they think matters, and forms a starting point for how to proceed.
Allergic contact dermatitis Mechanism Allergic_contact_dermatitis > Mechanism As the LCs are transported to the lymph nodes, they become differentiated and transform into DCs, which are immunostimulatory in nature. Once within the lymph glands, the differentiated DCs present the allergenic epitope associated with the allergen to T lymphocytes. These T cells then divide and differentiate, clonally multiplying so that if the allergen is experienced again by the individual, these T cells will respond more quickly and more aggressively.
Domain theory Special types of domains Domain_theory > A guide to the formal definitions > Special types of domains More special versions of both are continuous and algebraic cpos. Adding even further completeness properties one obtains continuous lattices and algebraic lattices, which are just complete lattices with the respective properties. For the algebraic case, one finds broader classes of posets that are still worth studying: historically, the Scott domains were the first structures to be studied in domain theory.
Multivariate function Multivariable differentiability Functions_of_several_real_variables > Calculus > Multivariable differentiability Also, df can be construed as a covector with basis vectors as the infinitesimals dxi in each direction and partial derivatives of f as the components. Geometrically ∇f is perpendicular to the level sets of f, given by f(x) = c which for some constant c describes an (n − 1)-dimensional hypersurface.
Concurrent data structure Basic principles Concurrent_data_structure > Basic principles Therefore, many mainstream approaches for arguing the safety properties of a concurrent data structure (such as serializability, linearizability, sequential consistency, and quiescent consistency) specify the structures properties sequentially, and map its concurrent executions to a collection of sequential ones. To guarantee the safety and liveness properties, concurrent data structures must typically (though not always) allow threads to reach consensus as to the results of their simultaneous data access and modification requests. To support such agreement, concurrent data structures are implemented using special primitive synchronization operations (see synchronization primitives) available on modern multiprocessor machines that allow multiple threads to reach consensus. This consensus can be achieved in a blocking manner by using locks, or without locks, in which case it is non-blocking. There is a wide body of theory on the design of concurrent data structures (see bibliographical references).
Domain-general learning Language Domain-general_learning > Skills That May Be Acquired via Domain-General Mechanisms > Language The general cognitive processes perspective of language development emphasizes characteristics of the language learner as the source of development. The general cognitive processes perspective states that the broad cognitive processes are sufficient for a child to learn new words. These broad cognitive processes include: attending, perceiving, and remembering.
Thing Description Property Thing_Description > Principles > Property An Interaction Affordance that exposes state of an IoT device. This state can then be retrieved (read) and optionally updated (write). Devices can also choose to make Properties observable by pushing the new state after a change.
Backward chaining Summary Backward_reasoning Both rules are based on the modus ponens inference rule. It is one of the two most commonly used methods of reasoning with inference rules and logical implications – the other is forward chaining. Backward chaining systems usually employ a depth-first search strategy, e.g. Prolog.
Device-to-device D2D applications Device-to-device > D2D applications IoT Enhancement: By combining D2D with Internet of things (IoT), a truly interconnected wireless network will be created. Example of D2D-based IoT enhancement is vehicle-to-vehicle (V2V) communication in the Internet of Vehicles (IoV). When running at high speeds, a vehicle can warn nearby vehicles in D2D mode before it changes lanes or slows down.
Drug-resistant tuberculosis Drug-induced hepatitis Antitubercular_agents > Adverse effects > Drug-induced hepatitis Liver function tests (LFTs) should be checked at the start of treatment, but, if normal, need not be checked again; the patient need only be warned of the symptoms of hepatitis. Some clinicians insist on regular monitoring of LFT's while on treatment, and in this instance, tests need only be done two weeks after starting treatment and then every two months thereafter, unless any problems are detected. Elevations in bilirubin must be expected with RMP treatment (RMP blocks bilirubin excretion) and usually resolve after 10 days (liver enzyme production increases to compensate).
Lift-induced drag Explanation Lift-induced_drag > Explanation To change the direction of the flow therefore requires that a force be applied to the fluid; the total aerodynamic force is simply the reaction force of the fluid acting on the wing. An aircraft in slow flight at a high angle of attack will generate an aerodynamic reaction force with a high drag component.
Frequency histogram Mathematical definitions Frequency_histogram > Mathematical definitions This yields a smoother probability density function, which will in general more accurately reflect distribution of the underlying variable. The density estimate could be plotted as an alternative to the histogram, and is usually drawn as a curve rather than a set of boxes. Histograms are nevertheless preferred in applications, when their statistical properties need to be modeled. The correlated variation of a kernel density estimate is very difficult to describe mathematically, while it is simple for a histogram where each bin varies independently. An alternative to kernel density estimation is the average shifted histogram, which is fast to compute and gives a smooth curve estimate of the density without using kernels.
Velocity (character) Cyberforce Volume 3: Rising From the Ashes Velocity_(character) > Fictional character biography > Cyberforce Volume 3: Rising From the Ashes In the third volume of Cyberforce, released in June, 2006, Cyberdata is finally destroyed. However, the company releases a failsafe virus meant to kill all those on the planet infected with the alien technology. In this Marc Silvestri re-introduction of Cyberforce, Ripclaw and Velocity are betrayed by the captain of the vessel that helped them reach Antarctica, and flee to the ruins. Once inside, the tunnel collapses, burying them alive.
Evolutionary approaches to schizophrenia Summary Evolutionary_approaches_to_schizophrenia It has been found to present cross-culturally, and it almost always has 0.1% prevalence in a given population, although some studies have cast doubts on this. Schizophrenia has been hypothesized to be unique to human beings and existing for a long time.Schizophrenia has raised a perplexing question for evolutionary psychologists and anthropologists. Why has such a debilitating disorder persisted for so long, with such frequency?
Fluorescent glucose biosensor Tissue autofluorescence Fluorescent_glucose_biosensors > Tissue autofluorescence Another pair of papers suggest that the natural fluorescence (autofluorescence) of tissues may be harnessed to track glucose concentrations. These studies took advantage of the fact that NAD(P)H, in its reduced form, is autofluorescent, and that metabolites such as glucose cause a predictable increase in NAD(P)H reduction.
Point-to-point encryption Merchant benefits Point_to_Point_Encryption > Benefits > Merchant benefits P2PE significantly facilitates merchant responsibilities: With a P2PE validated solution, merchants save significant time and money as PCI requirements may be greatly reduced. Payment Card Industry Data Security Standard (PCI DSS). For organizations who use a P2PE validated solution provider, the PCI Self Assessment Questionnaire is reduced from 12 sections to 4 sections and the controls are reduced from 329 questions to just 35.
Intestinal mucosal barrier Cellular immunity Intestinal_mucosal_barrier > Composition > Immunological elements > Cellular immunity A variety of immune cells reside in the lamina propria which underlies the intestinal epithelium. These include dendritic cells (DCs), macrophages, intraepithelial lymphocytes (IEL), T regulatory cells (T Regs), TCD4+ lymphocytes, B lymphocytes, and plasma cells. This population provides immune protection that is characterised by the rapid detection and killing of microorganisms that penetrate the intestinal epithelium.
Scalar field (quantum field theory) Renormalization Scalar_field_theory > Quantum scalar field theory > Renormalization One can then make an expansion in powers of the coupling parameters and truncate the higher-order terms (also known as higher loop contributions, due to the number of loops in the corresponding Feynman graphs). The β-function at one loop (the first perturbative contribution) for the φ4 theory is β ( g ) = 3 16 π 2 g 2 + O ( g 3 ) . {\displaystyle \beta (g)={\frac {3}{16\pi ^{2}}}g^{2}+O\left(g^{3}\right)~.}
Visual Basic (.NET) Simple example Visual_Basic_(.NET) > Syntax > Simple example Modules are a division of code, which can contain any kind of object, like constants or variables, functions or methods, or classes, but can't be instantiated as objects like classes and cannot inherit from other modules. Modules serve as containers of code that can be referenced from other parts of a program.It is common practice for a module and the code file which contains it to have the same name. However, this is not required, as a single code file may contain more than one module and/or class.

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