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It was designed by Ricardo Velázquez Bosco. Like some other buildings by this architect, it features ceramic decorations by Daniel Zuloaga. It was declared Bien de Interés Cultural in 1985. | Wikipedia - School of Mining Engineering of Madrid | null | null | null |
It was designed by artists Elena Engelsen and Per Ung, who spent over a year collaborating on the project. Engelsen created the exotic animal characters star, while Ung designed the human characters in the zodiac. This was the couple’s second joint artwork venture. | Wikipedia - Oslo Astrological Clock | null | null | null |
It was determined that each Chapter would have its own Council, the overall activities being determined by the Governing Board, on which each Council was represented, and an executive committee. | Wikipedia - Tissue Engineering and Regenerative Medicine International Society | null | null | null |
It was discovered that Tarski-like semantics for intuitionistic logic were not possible to prove complete. However, Robert Constable has shown that a weaker notion of completeness still holds for intuitionistic logic under a Tarski-like model. In this notion of completeness we are concerned not with all of the statemen... | Wikipedia - Constructivist logic | null | null | null |
It was discovered that in the United States between 180,000 and 500,000 rape kits were left unprocessed in storage in forensic warehouses. Registration and entry of criminal DNA had been inconsistent, which caused this large backlog in date rape kits. The delay in analysing these DNA samples would approximately be six ... | Wikipedia - Data activism | null | null | null |
Testing these rape kits is important in identifying and prosecuting offenders, recognizing serial rapists, and providing justice for rape victims. The Ending the Backlog Initiative brought attention to this issue by demanding that the data from these rape kits be processed. It was this initiative that brought this issu... | Wikipedia - Data activism | null | null | null |
It was first consciously applied to modern physics by Frederick Soddy when he, along with Ernest Rutherford in 1901, discovered that radioactive thorium was converting itself into radium. At the moment of realization, Soddy later recalled, he shouted out: "Rutherford, this is transmutation!" Rutherford snapped back, "F... | Wikipedia - Nuclear transmutation | null | null | null |
"Rutherford and Soddy were observing natural transmutation as a part of radioactive decay of the alpha decay type. The first artificial transmutation was accomplished in 1925 by Patrick Blackett, a research fellow working under Rutherford, with the transmutation of nitrogen into oxygen, using alpha particles directed a... | Wikipedia - Nuclear transmutation | null | null | null |
Blackett correctly identified the underlying integration process and the identity of the residual nucleus. In 1932, a fully artificial nuclear reaction and nuclear transmutation was achieved by Rutherford's colleagues John Cockcroft and Ernest Walton, who used artificially accelerated protons against lithium-7 to split... | Wikipedia - Nuclear transmutation | null | null | null |
In 1941, Rubby Sherr, Kenneth Bainbridge and Herbert Lawrence Anderson reported the nuclear transmutation of mercury into gold.Later in the twentieth century the transmutation of elements within stars was elaborated, accounting for the relative abundance of heavier elements in the universe. Save for the first five elem... | Wikipedia - Nuclear transmutation | null | null | null |
It was first isolated from the seed of Chamaecyparis obtusa (Cupressaceae) and then from the leaves of Cryptomeria japonica D. Don. Chamaecydin has since been found to be unique to the swamp cypress subfamily (Taxodioideae), specifically, it has been most studied in these species: Cryptomeria japonica, Glyptostrobus pe... | Wikipedia - Chamaecydin | null | null | null |
It was from the development of the Normative Scenario, that the Army Corps of Engineers developed CERP, the Comprehensive Everglades Restoration Plan. In the plan they created a time line of projects to be completed, the estimated cost and the ultimate results of improving the ecosystem by having native flora and fauna... | Wikipedia - Earth systems engineering and management | null | null | null |
It was ideal to mine stones from quarries that were situated as close to the site of construction as possible, to reduce the cost of transportation. Stone blocks were formed in quarries by punching holes in lines at the desired lengths and widths. Then, wooden wedges were hammered into the holes. The holes were then fi... | Wikipedia - Roman technology | null | null | null |
Blocks with the dimensions of 23yds by 14 ft by 15 ft have been found, with weights of about 1000 tons. There is evidence that saws were developed to cut stone in the Imperial age. Initially, Romans used saws powered by hand to cut stone, but later went on to develop stone cutting saws powered by water. | Wikipedia - Roman technology | null | null | null |
It was in 1993 that the Army Corps of Engineers analyzed the system. They determined that an ideal situation would be to "get the water right". In doing so there would be a better flow through the Everglades and a reduced number of canals and levees sending water to tide. | Wikipedia - Earth systems engineering and management | null | null | null |
It was in particular the inability to have good control over the space of solutions to Gauss's law and spatial diffeomorphism constraints that led Rovelli and Smolin to consider the loop representation in gauge theories and quantum gravity.LQG includes the concept of a holonomy. A holonomy is a measure of how much the ... | Wikipedia - Loop gravity | null | null | null |
For a closed loop x = y {\displaystyle x=y} and assuming α = β {\displaystyle \alpha =\beta } , yields ( h e ′ ) α α = U α γ − 1 ( x ) ( h e ) γ σ U σ α ( x ) = ( h e ) γ σ = δ σ γ ( h e ) γ σ = ( h e ) γ γ {\displaystyle (h'_{e})_{\alpha \alpha }=U_{\alpha \gamma }^{-1}(x)(h_{e})_{\gamma \sigma }U_{\sigma \alpha }(x)... | Wikipedia - Loop gravity | null | null | null |
Thus Wilson loops are gauge invariant. The explicit form of the Holonomy is h γ = P exp { − ∫ γ 0 γ 1 d s γ ˙ a A a i ( γ ( s ) ) T i } {\displaystyle h_{\gamma }={\mathcal {P}}\exp \left\{-\int _{\gamma _{0}}^{\gamma _{1}}ds{\dot {\gamma }}^{a}A_{a}^{i}(\gamma (s))T_{i}\right\}} where γ {\displaystyle \gamma } is t... | Wikipedia - Loop gravity | null | null | null |
The Pauli matrices satisfy the above relation. It turns out that there are infinitely many more examples of sets of matrices that satisfy these relations, where each set comprises ( N + 1 ) × ( N + 1 ) {\displaystyle (N+1)\times (N+1)} matrices with N = 1 , 2 , 3 , … {\displaystyle N=1,2,3,\dots } , and where none of t... | Wikipedia - Loop gravity | null | null | null |
The most fundamental representation being the Pauli matrices. The holonomy is labelled by a half integer N / 2 {\displaystyle N/2} according to the irreducible representation used. The use of Wilson loops explicitly solves the Gauss gauge constraint. | Wikipedia - Loop gravity | null | null | null |
Loop representation is required to handle the spatial diffeomorphism constraint. With Wilson loops as a basis, any Gauss gauge invariant function expands as, Ψ = ∑ γ Ψ W γ . | Wikipedia - Loop gravity | null | null | null |
{\displaystyle \Psi =\sum _{\gamma }\Psi W_{\gamma }.} This is called the loop transform and is analogous to the momentum representation in quantum mechanics (see Position and momentum space). The QM representation has a basis of states exp ( i k x ) {\displaystyle \exp(ikx)} labelled by a number k {\displaystyle k} ... | Wikipedia - Loop gravity | null | null | null |
{\displaystyle \psi =\int dk\psi (k)\exp(ikx).} and works with the coefficients of the expansion ψ ( k ) . {\displaystyle \psi (k).} | Wikipedia - Loop gravity | null | null | null |
The inverse loop transform is defined by Ψ = ∫ Ψ W γ . {\displaystyle \Psi =\int \Psi W_{\gamma }.} This defines the loop representation. | Wikipedia - Loop gravity | null | null | null |
Given an operator O ^ {\displaystyle {\hat {O}}} in the connection representation, Φ = O ^ Ψ E q 1 , {\displaystyle \Phi ={\hat {O}}\Psi \qquad Eq\;1,} one should define the corresponding operator O ^ ′ {\displaystyle {\hat {O}}'} on Ψ {\displaystyle \Psi } in the loop representation via, Φ = O ^ ′ Ψ E q 2 , {\dis... | Wikipedia - Loop gravity | null | null | null |
of E q 2 {\displaystyle Eq\;2} with the R.H.S. of E q 3 {\displaystyle Eq\;3} with E q 1 {\displaystyle Eq\;1} substituted into E q 3 {\displaystyle Eq\;3} , namely O ^ ′ Ψ = ∫ W γ O ^ Ψ , {\displaystyle {\hat {O}}'\Psi =\int W_{\gamma }{\hat {O}}\Psi ,} or O ^ ′ Ψ = ∫ ( O ^ † W γ ) Ψ , {\displaystyle {\hat {O}... | Wikipedia - Loop gravity | null | null | null |
This gives the physical meaning of the operator O ^ ′ {\displaystyle {\hat {O}}'} . For example, if O ^ † {\displaystyle {\hat {O}}^{\dagger }} corresponded to a spatial diffeomorphism, then this can be thought of as keeping the connection field A {\displaystyle A} of W γ {\displaystyle W_{\gamma }} where it is while ... | Wikipedia - Loop gravity | null | null | null |
In the loop representation, the spatial diffeomorphism constraint is solved by considering functions of loops Ψ {\displaystyle \Psi } that are invariant under spatial diffeomorphisms of the loop γ {\displaystyle \gamma } . That is, knot invariants are used. This opens up an unexpected connection between knot theory an... | Wikipedia - Loop gravity | null | null | null |
Any collection of non-intersecting Wilson loops satisfy Ashtekar's quantum Hamiltonian constraint. Using a particular ordering of terms and replacing E ~ i a {\displaystyle {\tilde {E}}_{i}^{a}} by a derivative, the action of the quantum Hamiltonian constraint on a Wilson loop is H ~ ^ † W γ = − ϵ i j k F ^ a b k δ δ ... | Wikipedia - Loop gravity | null | null | null |
{\displaystyle {\hat {\tilde {H}}}^{\dagger }W_{\gamma }=-\epsilon _{ijk}{\hat {F}}_{ab}^{k}{\frac {\delta }{\delta A_{a}^{i}}}{\frac {\delta }{\delta A_{b}^{j}}}W_{\gamma }.} When a derivative is taken it brings down the tangent vector, γ ˙ a {\displaystyle {\dot {\gamma }}^{a}} , of the loop, γ {\displaystyle \gamma ... | Wikipedia - Loop gravity | null | null | null |
{\displaystyle {\hat {F}}_{ab}^{i}{\dot {\gamma }}^{a}{\dot {\gamma }}^{b}.} However, as F a b i {\displaystyle F_{ab}^{i}} is anti-symmetric in the indices a {\displaystyle a} and b {\displaystyle b} this vanishes (this assumes that γ {\displaystyle \gamma } is not discontinuous anywhere and so the tangent vector is u... | Wikipedia - Loop gravity | null | null | null |
With regard to loop representation, the wavefunctions Ψ {\displaystyle \Psi } vanish when the loop has discontinuities and are knot invariants. Such functions solve the Gauss law, the spatial diffeomorphism constraint and (formally) the Hamiltonian constraint. This yields an infinite set of exact (if only formal) solu... | Wikipedia - Loop gravity | null | null | null |
It was in the 16th century, during the Early Modern period of British history, that further written accounts of the Rollrights were made; one of the earliest of these was provided by the pioneering antiquarian John Leland (c.1503–1552) in his unpublished account of his travels across England, Itinerary. Nonetheless, de... | Wikipedia - Rollright Stones | null | null | null |
It was in the course of proving of the existence of an optimal equilibrium in his 1937 model of economic growth that John von Neumann introduced functional analytic methods to include topology in economic theory, in particular, fixed-point theory through his generalization of Brouwer's fixed-point theorem. Following vo... | Wikipedia - Mathematical economist | null | null | null |
In their models, the ("primal") vector space represented quantities while the "dual" vector space represented prices.In Russia, the mathematician Leonid Kantorovich developed economic models in partially ordered vector spaces, that emphasized the duality between quantities and prices. Kantorovich renamed prices as "obj... | Wikipedia - Mathematical economist | null | null | null |
It was known before the genomic era that clustered genes tend to be functionally related. Abderrahim et al. (1994) had shown that all the genes of the major histocompatibility complex were clustered on the 6p21 chromosome. Roy et al. (2002) showed that in the nematode C. elegans genes that are solely expressed in muscl... | Wikipedia - Ridge (biology) | null | null | null |
Yamashita et al. (2004) showed that genes related to specific functions in organs tend to cluster. Six liver related domains contained genes for xenobiotic, lipid and alcohol metabolism. Five colon-related domains had genes for apoptosis, cell proliferation, ion transporter and mucin production. | Wikipedia - Ridge (biology) | null | null | null |
These clusters were very small and expression levels were low. Brain and breast related genes didn't cluster.This shows that at least some clusters consist of functionally related genes. However, there are great exceptions. Spellman and Rubin have shown that there are clusters of co-expressed genes that are not functio... | Wikipedia - Ridge (biology) | null | null | null |
It was listed by The Guardian in 2004 as one of the "100 most useful websites", being "the best" for predictions. In 2012 it was described by PhD student Chris Prosser at the University of Oxford as "probably the leading vote/seat predictor on the internet". Its detailed predictions for individual seats have been noted... | Wikipedia - Electoral Calculus | null | null | null |
It was long assumed that the midbody was simply a structural part of cytokinesis, and was totally degraded with the completion of mitosis. However, it is now understood that post-abscission, the midbody is converted into an endosome-like signalling molecule, and can be internalised by nearby cells.This endosome is mark... | Wikipedia - Midbody (cell biology) | null | null | null |
It was made in the late 1970s and early 1980s to make it easier for travel consultants to check availability and make bookings for holidays. A number of Viewdata bulletin board systems existed in the 1980s, predominantly in the UK due to the proliferation of the BBC Micro, and a short-lived Viewdata Revival appeared in... | Wikipedia - Viewdata | null | null | null |
It was not recognized until the 1970s, but nickel is known to play an important role in the biology of some plants, bacteria, archaea, and fungi. Nickel enzymes such as urease are considered virulence factors in some organisms. Urease catalyzes hydrolysis of urea to form ammonia and carbamate. | Wikipedia - Nickel | null | null | null |
NiFe hydrogenases can catalyze oxidation of H2 to form protons and electrons; and also the reverse reaction, the reduction of protons to form hydrogen gas. A nickel-tetrapyrrole coenzyme, cofactor F430, is present in methyl coenzyme M reductase, which can catalyze the formation of methane, or the reverse reaction, in m... | Wikipedia - Nickel | null | null | null |
Other nickel-bearing enzymes include a rare bacterial class of superoxide dismutase and glyoxalase I enzymes in bacteria and several eukaryotic trypanosomal parasites (in other organisms, including yeast and mammals, this enzyme contains divalent Zn2+).Dietary nickel may affect human health through infections by nickel... | Wikipedia - Nickel | null | null | null |
Estimated dietary intake is 70 to 100 µg/day; less than 10% is absorbed. What is absorbed is excreted in urine. Relatively large amounts of nickel – comparable to the estimated average ingestion above – leach into food cooked in stainless steel. For example, the amount of nickel leached after 10 cooking cycles into one... | Wikipedia - Nickel | null | null | null |
It was not until the 19th century that a Swiss mathematician, Ludwig Schläfli, examined and characterised the regular polytopes in higher dimensions. His efforts were first published in full in Schläfli (1901), six years posthumously, although parts of it were published in Schläfli (1855) and Schläfli (1858). Between 1... | Wikipedia - Regular (geometry) | null | null | null |
Schläfli called such a figure a "polyschem" (in English, "polyscheme" or "polyschema"). The term "polytope" was introduced by Reinhold Hoppe, one of Schläfli's rediscoverers, in 1882, and first used in English by Alicia Boole Stott some twenty years later. The term "polyhedroids" was also used in earlier literature (Hi... | Wikipedia - Regular (geometry) | null | null | null |
Coxeter (1973) is probably the most comprehensive printed treatment of Schläfli's and similar results to date. Schläfli showed that there are six regular convex polytopes in 4 dimensions. Five of them can be seen as analogous to the Platonic solids: the 4-simplex (or pentachoron) to the tetrahedron, the hypercube (or t... | Wikipedia - Regular (geometry) | null | null | null |
The sixth, the 24-cell, can be seen as a transitional form between the hypercube and 16-cell, analogous to the way that the cuboctahedron and the rhombic dodecahedron are transitional forms between the cube and the octahedron. In five and more dimensions, there are exactly three regular polytopes, which correspond to t... | Wikipedia - Regular (geometry) | null | null | null |
Also of interest are the star regular 4-polytopes, partially discovered by Schläfli. By the end of the 19th century, mathematicians such as Arthur Cayley and Ludwig Schläfli had developed the theory of regular polytopes in four and higher dimensions, such as the tesseract and the 24-cell. The latter are difficult (thou... | Wikipedia - Regular (geometry) | null | null | null |
The tesseract contains 8 cubical cells. It consists of two cubes in parallel hyperplanes with corresponding vertices cross-connected in such a way that the 8 cross-edges are equal in length and orthogonal to the 12+12 edges situated on each cube. The corresponding faces of the two cubes are connected to form the remain... | Wikipedia - Regular (geometry) | null | null | null |
The 24-cell can be derived from the tesseract by joining the 8 vertices of each of its cubical faces to an additional vertex to form the four-dimensional analogue of a pyramid. Both figures, as well as other 4-dimensional figures, can be directly visualised and depicted using 4-dimensional stereographs.Harder still to ... | Wikipedia - Regular (geometry) | null | null | null |
At the start of the 20th century, the definition of a regular polytope was as follows. A regular polygon is a polygon whose edges are all equal and whose angles are all equal. A regular polyhedron is a polyhedron whose faces are all congruent regular polygons, and whose vertex figures are all congruent and regular. | Wikipedia - Regular (geometry) | null | null | null |
And so on, a regular n-polytope is an n-dimensional polytope whose (n − 1)-dimensional faces are all regular and congruent, and whose vertex figures are all regular and congruent.This is a "recursive" definition. It defines regularity of higher dimensional figures in terms of regular figures of a lower dimension. There... | Wikipedia - Regular (geometry) | null | null | null |
An n-polytope is regular if any set consisting of a vertex, an edge containing it, a 2-dimensional face containing the edge, and so on up to n−1 dimensions, can be mapped to any other such set by a symmetry of the polytope.So for example, the cube is regular because if we choose a vertex of the cube, and one of the thr... | Wikipedia - Regular (geometry) | null | null | null |
It was not until the 20th century that advances in the understanding of atmospheric physics led to the foundation of modern numerical weather prediction. In 1922, English scientist Lewis Fry Richardson published "Weather Prediction By Numerical Process", after finding notes and derivations he worked on as an ambulance ... | Wikipedia - Weather bulletin | null | null | null |
However, the sheer number of calculations required was too large to be completed without the use of computers, and the size of the grid and time steps led to unrealistic results in deepening systems. It was later found, through numerical analysis, that this was due to numerical instability. The first computerised weath... | Wikipedia - Weather bulletin | null | null | null |
It was not, however, as a theorist dealing with the fundamental data of economic science, but as a writer on practical economic questions, that Jevons first received general recognition. A Serious Fall in the Value of Gold (1863) and The Coal Question (1865) placed him in the front rank as a writer on applied economics... | Wikipedia - Logical piano | null | null | null |
He was engaged at the time of his death upon the preparation of a large treatise on economics and had drawn up a table of contents and completed some chapters and parts of chapters. This fragment was published in 1905 under the title of The Principles of Economics: a fragment of a treatise on the industrial mechanism o... | Wikipedia - Logical piano | null | null | null |
The Coal Question remains a paradigmatic study of resource depletion theory. Jevons's son, H. Stanley Jevons, published an 800-page follow-up study in 1915 in which the difficulties of estimating recoverable reserves of a theoretically finite resource are discussed in detail.In 1875, Jevons read a paper On the influenc... | Wikipedia - Logical piano | null | null | null |
In a later work, "Commercial Crises and Sun-Spots", Jevons analyzed business cycles, proposing that crises in the economy might not be random events, but might be based on discernible prior causes. To clarify the concept, he presented a statistical study relating business cycles with sunspots. | Wikipedia - Logical piano | null | null | null |
His reasoning was that sunspots affected the weather, which, in turn, affected crops. Crop changes could then be expected to cause economic changes. Subsequent studies have found that sunny weather has a small but significant positive impact on stock returns, probably due to its impact on traders' moods. | Wikipedia - Logical piano | null | null | null |
It was only in the 19th century that debates over technological unemployment became intense, especially in Great Britain where many economic thinkers of the time were concentrated. Building on the work of Dean Tucker and Adam Smith, political economists began to create what would become the modern discipline of economi... | Wikipedia - Luddite fallacy | null | null | null |
These included Sismondi, Malthus, J S Mill, and from 1821, David Ricardo himself. As arguably the most respected political economist of his age, Ricardo's view was challenging to others in the discipline. | Wikipedia - Luddite fallacy | null | null | null |
The first major economist to respond was Jean-Baptiste Say, who argued that no one would introduce machinery if they were going to reduce the amount of product, and that as Say's Law states that supply creates its own demand, any displaced workers would automatically find work elsewhere once the market had had time to ... | Wikipedia - Luddite fallacy | null | null | null |
Building on the work of Ricardo and Mill, Marx went much further, presenting a deeply pessimistic view of technological unemployment; his views attracted many followers and founded an enduring school of thought but mainstream economics was not dramatically changed. By the 1870s, at least in Great Britain, technological... | Wikipedia - Luddite fallacy | null | null | null |
It was originally assumed that geographic isolation was a necessary precursor to speciation (allopatric speciation). The possibility that clines may be a precursor to speciation was therefore ignored, as they were assumed to be evidence of the fact that in contiguous populations gene flow was too strong a force of homo... | Wikipedia - Cline (biology) | null | null | null |
Both extrinsic and intrinsic selection can serve to generate varying degrees of reproductive isolation and thereby instigate the process of speciation. For example, through environmental selection acting on populations and favouring particular allele frequencies, large genetic differences between populations may accumu... | Wikipedia - Cline (biology) | null | null | null |
If the local genetic differences are great enough, it may lead unfavourable combinations of genotypes and therefore to hybrids being at a decreased fitness relative to the parental lines. When this hybrid disadvantage is great enough, natural selection will select for pre-zygotic traits in the homozygous parental lines... | Wikipedia - Cline (biology) | null | null | null |
It was physically clear to Heisenberg that the absolute squares of the matrix elements of X, which are the Fourier coefficients of the oscillation, would yield the rate of emission of electromagnetic radiation. In the classical limit of large orbits, if a charge with position X(t) and charge q is oscillating next to an... | Wikipedia - Matrix Mechanics | null | null | null |
Since the transition rates are given by the matrix elements of X, wherever Xij is zero, the corresponding transition should be absent. These were called the selection rules, which were a puzzle until the advent of matrix mechanics. | Wikipedia - Matrix Mechanics | null | null | null |
An arbitrary state of the Hydrogen atom, ignoring spin, is labelled by |n;ℓ,m ⟩, where the value of ℓ is a measure of the total orbital angular momentum and m is its z-component, which defines the orbit orientation. The components of the angular momentum pseudovector are where the products in this expression are indepe... | Wikipedia - Matrix Mechanics | null | null | null |
Similarly, (X− iY) decrease m by one unit, while Z does not change the value of m. So, in a basis of |ℓ,m⟩ states where L2 and Lz have definite values, the matrix elements of any of the three components of the position are zero, except when m is the same or changes by one unit. This places a constraint on the change in... | Wikipedia - Matrix Mechanics | null | null | null |
It was pointed out in that the first statement below is equivalent to SSA and A. Ulhmann in showed the equivalence between the second statement below and SSA. S ( ρ 1 ) + S ( ρ 3 ) − S ( ρ 12 ) − S ( ρ 23 ) ≤ 0. {\displaystyle S(\rho ^{1})+S(\rho ^{3})-S(\rho ^{12})-S(\rho ^{23})\leq 0.} Note that the conditional entro... | Wikipedia - Strong Subadditivity of Quantum Entropy | null | null | null |
It was proposed by Elliott that other classes of C*-algebras may be classifiable by K-theoretic invariants. For a C*-algebra A, the Elliott invariant is defined to be Ell ( A ) = def ( ( K 0 ( A ) , K 0 ( A ) + , Γ ( A ) ) , K 1 ( A ) , T + ( A ) , ρ A ) , {\displaystyle {\mbox{Ell}}(A)\;{\stackrel {\mbox{def}}{=}}\;(\... | Wikipedia - Approximately finite dimensional C*-algebra | null | null | null |
It was proved by Masur and Minsky that the complex of curves is a Gromov hyperbolic space. Later work by various authors gave alternate proofs of this fact and better information on the hyperbolicity. | Wikipedia - Curve complex | null | null | null |
It was said in 2013 that "there is no universally accepted definition for the terms 'strain', 'variant', and 'isolate' in the virology community, and most virologists simply copy the usage of terms from others". The lack of precise definition continued in 2020; in the context of the Variant of Concern 202012/01 version... | Wikipedia - Variant (biology) | null | null | null |
It was suggested by the Department for Education that the high proportion of candidates who obtain grade A makes it difficult for universities to distinguish between the most able candidates. As a result, the 2010 exam session introduced the grade A*—which serves to distinguish between the better candidates.Prior to th... | Wikipedia - Advanced level mathematics | null | null | null |
The same minimum score of 480/600 was required across all six modules. However, a 90% average (or a score of 270/300) had to be obtained across the candidate's best 'A2' modules. A2 modules included any modules other than those with a '1' (FP1, S1, M1 and D1 are not A2 modules, whereas FP2, FP3, FP4 (from AQA only), S2... | Wikipedia - Advanced level mathematics | null | null | null |
It was suggested that the Astrobiology Field Laboratory use radioisotope thermoelectric generators (RTGs) as its power source, like the ones to be used on the Mars Science Laboratory. The radioactive RTG power source was to last for about one Martian year, or approximately two Earth years. RTGs can provide reliable, co... | Wikipedia - Astrobiology Field Laboratory | null | null | null |
It was suggested that the problem with building and maintaining larger, more complex, and more accurately replicated molecules can be circumvented if several information carriers, each of them storing a small piece of information, are connected such that they only control their own concentration. Studies of the mathema... | Wikipedia - Hypercycle (chemistry) | null | null | null |
Such a concept, apart from an increased information capacity, has another advantage. Linking self-replication with mutual catalysis can produce nonlinear growth of the system. This, first, makes the system resistant to so-called parasitic branches. | Wikipedia - Hypercycle (chemistry) | null | null | null |
Parasitic branches are species coupled to a cycle that do not provide any advantage to the reproduction of a cycle, which, in turn, makes them useless and decreases the selective value of the system. Secondly, it reinforces the self-organization of molecules into the hypercycle, allowing the system to evolve without lo... | Wikipedia - Hypercycle (chemistry) | null | null | null |
At the time of the hypercycle theory formulation, enzymatic properties were attributed only to proteins, while nucleic acids were recognized only as carriers of information. This led to the formulation of a more complex model of a hypercycle with translation. The proposed model consists of a number of nucleotide sequen... | Wikipedia - Hypercycle (chemistry) | null | null | null |
Sequences I have a limited chain length and carry the information necessary to build catalytic chains E. The sequence Ii provides the matrix to reproduce itself and a matrix to build the protein Ei. The protein Ei gives the catalytic support to build the next sequence in the cycle, Ii+1. The self-replicating sequences ... | Wikipedia - Hypercycle (chemistry) | null | null | null |
Therefore, many cycles of the +/− nucleotide collectives are linked together by the second-order cycle of enzymatic properties of E, forming a catalytic hypercycle. Without the secondary loop provided by catalysis, I chains would compete and select against each other instead of cooperating. | Wikipedia - Hypercycle (chemistry) | null | null | null |
The reproduction is possible thanks to translation and polymerization functions encoded in I chains. In his principal work, Manfred Eigen stated that the E coded by the I chain can be a specific polymerase or an enhancer (or a silencer) of a more general polymerase acting in favour of formation of the successor of nucl... | Wikipedia - Hypercycle (chemistry) | null | null | null |
It was the first extended treatment of scheme theory written as a text intended to be accessible to graduate students. | Wikipedia - Hartshorne's Algebraic Geometry | null | null | null |
It was thought in early evolutionary biology that languages and species can be studied according to the same principles and methods. The idea of languages and cultures as fighting for living space became highly controversial as it was accused of being a pseudoscience that caused two world wars, and social Darwinism was... | Wikipedia - Theory of language | null | null | null |
In this thinking, ideas and cultural units, including words, are compared to viruses or replicators. Although meant as a softer alternative to genetic determinism, memetics has been widely discredited as pseudoscience, and it has failed to establish itself as a recognised field of scientific research. | Wikipedia - Theory of language | null | null | null |
The language–species analogy nonetheless continues to enjoy popularity in linguistics and other human sciences. Since the 1990s there have been numerous attempts to revive it in various guises. As Jamin Pelkey explains,Theorists who explore such analogies usually feel obliged to pin language to some specific sub-domain... | Wikipedia - Theory of language | null | null | null |
William James selects "zoölogical evolution", William Croft prefers botanical evolution, but most theorists zoom in to more microbiotic levels – some claiming that linguistic phenomena are analogous to the cellular level and others arguing for the genetic level of biotic growth. For others, language is a parasite; for ... | Wikipedia - Theory of language | null | null | null |
It was understood in the 1960s that analyzing the air trapped in ice cores would provide useful information on the paleoatmosphere, but it was not until the late 1970s that a reliable extraction method was developed. Early results included a demonstration that the CO2 concentration was 30% less at the last glacial maxi... | Wikipedia - Ice core | null | null | null |
N2O (nitrous oxide) levels are also correlated with glacial cycles, though at low temperatures the graph differs somewhat from the CO2 and CH4 graphs. Similarly, the ratio between N2 (nitrogen) and O2 (oxygen) can be used to date ice cores: as air is gradually trapped by the snow turning to firn and then ice, O2 is los... | Wikipedia - Ice core | null | null | null |
Gravity causes heavier molecules to be enriched at the bottom of a gas column, with the amount of enrichment depending on the difference in mass between the molecules. Colder temperatures cause heavier molecules to be more enriched at the bottom of a column. These fractionation processes in trapped air, determined by t... | Wikipedia - Ice core | null | null | null |
It works exactly the same as CHANGE-EDGE except that instead of changing the ith edge of the vertex, we change the ith label. | Wikipedia - Ephemeral data structure | null | null | null |
It's also found that E-selectin expression increased in human ruptured cerebral aneurysm tissues. E-selectin might be an important factor involved in the process of cerebral aneurysm formation and rupture, by promoting inflammation and weakening cerebral artery walls. | Wikipedia - E-selectin | null | null | null |
It's important to understand that there are various framings/articulations of the engineering design process. Different terminology employed may have varying degrees of overlap, which affects what steps get stated explicitly or deemed "high level" versus subordinate in any given model. This, of course, applies as much ... | Wikipedia - Engineering design | null | null | null |
Others, noting that "different authors (in both research literature and in textbooks) define different phases of the design process with varying activities occurring within them," have suggested more simplified/generalized models – such as problem definition, conceptual design, preliminary design, detailed design, and ... | Wikipedia - Engineering design | null | null | null |
It's the combination of very low noise and superior contrast performance that allows some digital x-ray systems to offer such significant improvements in the detectability of low-contrast objects - a quality that is best quantified by a single parameter, the DQE. The DQE has become the de facto benchmark in the compari... | Wikipedia - Detective quantum efficiency | null | null | null |
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