text stringlengths 14 4.79k | source stringlengths 13 304 | tokens float64 75 1.06k ⌀ | char_length float64 106 4.79k ⌀ | article_title stringlengths 16 300 ⌀ |
|---|---|---|---|---|
Many models of quintessence have a tracker behavior, which according to Ratra and Peebles (1988) and Paul Steinhardt et al. (1999) partly solves the cosmological constant problem. In these models, the quintessence field has a density which closely tracks (but is less than) the radiation density until matter-radiation e... | Wikipedia - Quintessence (physics) | null | null | null |
Many models of the way the brain controls movement have been developed. This includes models of processing in the brain such as the cerebellum's role for error correction, skill learning in motor cortex and the basal ganglia, or the control of the vestibulo ocular reflex. This also includes many normative models, such ... | Wikipedia - Computational clinical neuroscience | null | null | null |
Many modern birds are highly social, often found living in flocks. There is general agreement that some behaviors that are common in birds, as well as in crocodiles (closest living relatives of birds), were also common among extinct dinosaur groups. Interpretations of behavior in fossil species are generally based on t... | Wikipedia - Dinosaur | null | null | null |
Those, along with multiple trackways, suggest that gregarious behavior was common in many early dinosaur species. Trackways of hundreds or even thousands of herbivores indicate that duck-billed (hadrosaurids) may have moved in great herds, like the American bison or the African springbok. Sauropod tracks document that ... | Wikipedia - Dinosaur | null | null | null |
Congregating into herds may have evolved for defense, for migratory purposes, or to provide protection for young. There is evidence that many types of slow-growing dinosaurs, including various theropods, sauropods, ankylosaurians, ornithopods, and ceratopsians, formed aggregations of immature individuals. | Wikipedia - Dinosaur | null | null | null |
One example is a site in Inner Mongolia that has yielded remains of over 20 Sinornithomimus, from one to seven years old. This assemblage is interpreted as a social group that was trapped in mud. The interpretation of dinosaurs as gregarious has also extended to depicting carnivorous theropods as pack hunters working t... | Wikipedia - Dinosaur | null | null | null |
However, this lifestyle is uncommon among modern birds, crocodiles, and other reptiles, and the taphonomic evidence suggesting mammal-like pack hunting in such theropods as Deinonychus and Allosaurus can also be interpreted as the results of fatal disputes between feeding animals, as is seen in many modern diapsid pred... | Wikipedia - Dinosaur | null | null | null |
It included a Velociraptor attacking a Protoceratops, providing evidence that dinosaurs did indeed attack each other. Additional evidence for attacking live prey is the partially healed tail of an Edmontosaurus, a hadrosaurid dinosaur; the tail is damaged in such a way that shows the animal was bitten by a tyrannosaur ... | Wikipedia - Dinosaur | null | null | null |
Although it has been suggested that most dinosaurs were active during the day, these comparisons have shown that small predatory dinosaurs such as dromaeosaurids, Juravenator, and Megapnosaurus were likely nocturnal. Large and medium-sized herbivorous and omnivorous dinosaurs such as ceratopsians, sauropodomorphs, hadr... | Wikipedia - Dinosaur | null | null | null |
While some early bird-like species may have already been arboreal as well (including dromaeosaurids) such as Microraptor) most non-avialan dinosaurs seem to have relied on land-based locomotion. A good understanding of how dinosaurs moved on the ground is key to models of dinosaur behavior; the science of biomechanics,... | Wikipedia - Dinosaur | null | null | null |
Many modern devices demand non-volatile memory requiring low power. Flash memory is used for these purposes. It is widespread in digital portable devices such as photo and video cameras, dictaphones, MP3 players, handheld computers, mobile phones, and also in smart phones and communicators. It is used for storage of th... | Wikipedia - Data card | null | null | null |
In recent years USB flash-drives have become more popular and have almost replaced diskettes and CDs. Flash memory is well known from its use in USB flash-drives. Flash cards also are based on flash memory, such as Secure Digital (SD), Compact Flash and Memory Stick. These are much used in portable devices (cameras, mo... | Wikipedia - Data card | null | null | null |
Many modern electronic devices are designed using quantum mechanics. Examples include lasers, electron microscopes, magnetic resonance imaging (MRI) devices and the components used in computing hardware. The study of semiconductors led to the invention of the diode and the transistor, which are indispensable parts of m... | Wikipedia - Applications of quantum mechanics | null | null | null |
The global positioning system (GPS) makes use of atomic clocks to measure precise time differences and therefore determine a user's location. Many electronic devices operate using the effect of quantum tunneling. Flash memory chips found in USB drives use quantum tunneling to erase their memory cells. | Wikipedia - Applications of quantum mechanics | null | null | null |
Some negative differential resistance devices also utilize the quantum tunneling effect, such as resonant tunneling diodes. Unlike classical diodes, its current is carried by resonant tunneling through two or more potential barriers (see figure at right). Its negative resistance behavior can only be understood with qua... | Wikipedia - Applications of quantum mechanics | null | null | null |
Many modern programming languages specify the double-quote character (") as a delimiter for a string literal. The backslash (\) escape character typically provides two ways to include double-quotes inside a string literal, either by modifying the meaning of the double-quote character embedded in the string (\" becomes ... | Wikipedia - Escape character | null | null | null |
The PostScript language and Microsoft Rich Text Format also use backslash escapes. The quoted-printable encoding uses the equals sign as an escape character. URL and URI use %-escapes to quote characters with a special meaning, as for non-ASCII characters. The ampersand (&) character may be considered as an escape char... | Wikipedia - Escape character | null | null | null |
Many modern programming languages, such as C++ and Java, come with standard libraries that implement several common ADTs, such as those listed above. | Wikipedia - Abstract data type | null | null | null |
Many modern steels and alloys are designed such that precipitates will precipitate either within the matrix or along grain boundaries during casting. These precipitates restrict dislocation motion and, if present on grain boundaries, grain boundary sliding during creep. Many precipitates are not thermodynamically stabl... | Wikipedia - Damage mechanics | null | null | null |
In the case of grain boundary precipitates, precipitate growth means that fewer grain boundaries are impeded from grain boundary sliding. When cast into the damage mechanics formalism, precipitation coarsening and its effect on strain rate may be represented by the following equations. ϵ ˙ = ϵ ˙ 0 σ n ( 1 + K ′ ′ ω ) n... | Wikipedia - Damage mechanics | null | null | null |
Many molecules and ions are described as dimers, even when the monomer is elusive. | Wikipedia - Dimerisation (chemistry) | null | null | null |
Many more complicated and intricate misere quotients have been calculated for various impartial games, and particularly for octal games. A general-purpose algorithm for computing the misere quotient monoid presentation of a given a finite set of misere impartial game positions has been devised by Aaron N. Siegel and is... | Wikipedia - Indistinguishability quotient | null | null | null |
Many more mood-based symptoms, grandiosity and guilt, may underlie functional paranoia.Colby (1981) defined paranoid cognition in terms of persecutory delusions and false beliefs whose propositional content clusters around ideas of being harassed, threatened, harmed, subjugated, persecuted, accused, mistreated, killed,... | Wikipedia - Paranoid ideation | null | null | null |
3). Paranoid cognition has been conceptualized by clinical psychology almost exclusively in terms of psychodynamic constructs and dispositional variables. From this point of view, paranoid cognition is a manifestation of an intra-psychic conflict or disturbance. | Wikipedia - Paranoid ideation | null | null | null |
For instance, Colby (1981) suggested that the biases of blaming others for one's problems serve to alleviate the distress produced by the feeling of being humiliated, and helps to repudiate the belief that the self is to blame for such incompetence. This intra-psychic perspective emphasizes that the cause of paranoid c... | Wikipedia - Paranoid ideation | null | null | null |
Even more, a model of trust development pointed out that trust increases or decreases as a function of the cumulative history of interaction between two or more persons.Another relevant difference can be discerned among "pathological and non-pathological forms of trust and distrust". According to Deutsch, the main diff... | Wikipedia - Paranoid ideation | null | null | null |
Many museums and cultural heritage centers recognize that given the diversity of artworks and cultural objects, no single model or standard suffices to describe and catalog cultural works. For example, a sculpted Indigenous artifact could be classified as an artwork, an archaeological artifact, or an Indigenous heritag... | Wikipedia - Metadata | null | null | null |
These standards use HTML and XML markup languages for machine processing, publication and implementation. The Anglo-American Cataloguing Rules (AACR), originally developed for characterizing books, have also been applied to cultural objects, works of art and architecture. Standards, such as the CCO, are integrated with... | Wikipedia - Metadata | null | null | null |
Scholars and professionals in the field note that the "quickly evolving landscape of standards and technologies" creates challenges for cultural documentarians, specifically non-technically trained professionals. Most collecting institutions and museums use a relational database to categorize cultural works and their i... | Wikipedia - Metadata | null | null | null |
Many mutually incompatible floppy disk formats are possible; aside from the physical format on the disk, incompatible file systems are also possible. Sides: SS (or 1S) – Single sided DS (or 2S) – Double sidedDensity: SD (or 1D) – Single density (FM) DD (or 2D) – Double density (most often MFM) QD (or 4D) – Quad density... | Wikipedia - Floppy Disk Controller | null | null | null |
Many myths have grown up about Einstein's relationship with quantum mechanics. Freshman physics students are aware that Einstein explained the photoelectric effect and introduced the concept of the photon. But students who have grown up with the photon may not be aware of how revolutionary the concept was for his time.... | Wikipedia - Einstein's thought experiments | null | null | null |
This has led to the general impression that, despite his initial contributions, Einstein was out of touch with quantum research and played at best a secondary role in its development. : 1–4 Concerning Einstein's estrangement from the general direction of physics research after 1925, his well-known scientific biographer... | Wikipedia - Einstein's thought experiments | null | null | null |
In the remaining 30 years of his life he remained active in research but his fame would be undiminished, if not enhanced, had he gone fishing instead. : 43 In hindsight, we know that Pais was incorrect in his assessment. Einstein was arguably the greatest single contributor to the "old" quantum theory. | Wikipedia - Einstein's thought experiments | null | null | null |
In his 1905 paper on light quanta, Einstein created the quantum theory of light. His proposal that light exists as tiny packets (photons) was so revolutionary, that even such major pioneers of quantum theory as Planck and Bohr refused to believe that it could be true. : 70–79, 282–284 Bohr, in particular, was a passion... | Wikipedia - Einstein's thought experiments | null | null | null |
In his 1906 theory of specific heats, Einstein was the first to realize that quantized energy levels explained the specific heat of solids. In this manner, he found a rational justification for the third law of thermodynamics (i.e. the entropy of any system approaches zero as the temperature approaches absolute zero): ... | Wikipedia - Einstein's thought experiments | null | null | null |
In 1909, using a rigorous fluctuation argument based on a thought experiment and drawing on his previous work on Brownian motion, he predicted the emergence of a "fusion theory" that would combine the two views. : 136–140 Basically, he demonstrated that the Brownian motion experienced by a mirror in thermal equilibrium... | Wikipedia - Einstein's thought experiments | null | null | null |
Furthermore, Planck's derivation represented an analysis of classical harmonic oscillators merged with quantum assumptions in an improvised fashion. : 184 In his 1916 theory of radiation, Einstein was the first to create a purely quantum explanation. This paper, well known for broaching the possibility of stimulated em... | Wikipedia - Einstein's thought experiments | null | null | null |
: 181–192 In 1924, Einstein received a short manuscript by an unknown Indian professor, Satyendra Nath Bose, outlining a new method of deriving the law of blackbody radiation. Einstein was intrigued by Bose's peculiar method of counting the number of distinct ways of putting photons into the available states, a method ... | Wikipedia - Einstein's thought experiments | null | null | null |
He translated the paper into German and had it published. Einstein then followed Bose's paper with an extension to Bose's work which predicted Bose–Einstein condensation, one of the fundamental research topics of condensed matter physics. : 215–240 While trying to develop a mathematical theory of light which would full... | Wikipedia - Einstein's thought experiments | null | null | null |
A guiding wave obeying Maxwell's classical laws would propagate following the normal laws of optics, but would not transmit any energy. This guiding wave, however, would govern the appearance of quanta of energy h ν {\displaystyle h\nu } on a statistical basis, so that the appearance of these quanta would be proportion... | Wikipedia - Einstein's thought experiments | null | null | null |
: 193–203 Therefore, Einstein before 1925 originated most of the key concepts of quantum theory: light quanta, wave-particle duality, the fundamental randomness of physical processes, the concept of indistinguishability, and the probability density interpretation of the wave equation. In addition, Einstein can arguably... | Wikipedia - Einstein's thought experiments | null | null | null |
He provided a correct derivation of the blackbody radiation law and sparked the notion of the laser. What of after 1925? | Wikipedia - Einstein's thought experiments | null | null | null |
In 1935, working with two younger colleagues, Einstein issued a final challenge to quantum mechanics, attempting to show that it could not represent a final solution. Despite the questions raised by this paper, it made little or no difference to how physicists employed quantum mechanics in their work. Of this paper, Pa... | Wikipedia - Einstein's thought experiments | null | null | null |
Many nitrogen oxoacids are known, though most of them are unstable as pure compounds and are known only as aqueous solutions or as salts. Hyponitrous acid (H2N2O2) is a weak diprotic acid with the structure HON=NOH (pKa1 6.9, pKa2 11.6). Acidic solutions are quite stable but above pH 4 base-catalysed decomposition occu... | Wikipedia - Nitrogen gas | null | null | null |
They are an intermediate step in the oxidation of ammonia to nitrite, which occurs in the nitrogen cycle. Hyponitrite can act as a bridging or chelating bidentate ligand.Nitrous acid (HNO2) is not known as a pure compound, but is a common component in gaseous equilibria and is an important aqueous reagent: its aqueous ... | Wikipedia - Nitrogen gas | null | null | null |
They may be titrimetrically analysed by their oxidation to nitrate by permanganate. They are readily reduced to nitrous oxide and nitric oxide by sulfur dioxide, to hyponitrous acid with tin(II), and to ammonia with hydrogen sulfide. Salts of hydrazinium N2H+5 react with nitrous acid to produce azides which further rea... | Wikipedia - Nitrogen gas | null | null | null |
Sodium nitrite is mildly toxic in concentrations above 100 mg/kg, but small amounts are often used to cure meat and as a preservative to avoid bacterial spoilage. It is also used to synthesise hydroxylamine and to diazotise primary aromatic amines as follows: ArNH2 + HNO2 → Cl + 2 H2ONitrite is also a common ligand tha... | Wikipedia - Nitrogen gas | null | null | null |
Nitro-nitrito isomerism is common, where the nitrito form is usually less stable. Nitric acid (HNO3) is by far the most important and the most stable of the nitrogen oxoacids. It is one of the three most used acids (the other two being sulfuric acid and hydrochloric acid) and was first discovered by alchemists in the 1... | Wikipedia - Nitrogen gas | null | null | null |
It is made by the catalytic oxidation of ammonia to nitric oxide, which is oxidised to nitrogen dioxide, and then dissolved in water to give concentrated nitric acid. In the United States of America, over seven million tonnes of nitric acid are produced every year, most of which is used for nitrate production for ferti... | Wikipedia - Nitrogen gas | null | null | null |
It can only be made in the solid state, because upon melting it spontaneously decomposes to nitrogen dioxide, and liquid nitric acid undergoes self-ionisation to a larger extent than any other covalent liquid as follows: 2 HNO3 ⇌ H2NO+3 + NO−3 ⇌ H2O + + + −Two hydrates, HNO3·H2O and HNO3·3H2O, are known that can be cry... | Wikipedia - Nitrogen gas | null | null | null |
Many non-profit organizations offer open access to their data, as long it does not undermine their users', members' or third party's privacy rights. In comparison to for-profit corporations, they do not seek to monetize their data. OpenNWT launched a website offering open data of elections. CIAT offers open data to any... | Wikipedia - Open Data | null | null | null |
Many numbers have been given humorous names, either as pure numbers or as units of measurement. Some examples: Sagan has been defined as "billions and billions", a metric of the number of stars in the observable universe.Jenny's constant has been defined as J = ( 7 e − 1 / e − 9 ) ⋅ π 2 = 867.5309 … . {\displaystyle J=... | Wikipedia - Mathematical joke | null | null | null |
This number appears as a fixed value in the TIFF image file format and its derivatives (including for example the ISO standard TIFF/EP) where the content of bytes 2–3 is defined as 42: "An arbitrary but carefully chosen number that further identifies the file as a TIFF file".The number 69 is commonly used in reference ... | Wikipedia - Mathematical joke | null | null | null |
Many observations can be made from dynamo models. Models can be used to estimate how magnetic fields vary with time and can be compared to observed paleomagnetic data to find similarities between the model and the Earth. Due to the uncertainty of paleomagnetic observations, however, comparisons may not be entirely vali... | Wikipedia - Dynamo mechanism | null | null | null |
Many of Aristotle's works are extremely compressed and thus baffling to beginners, and many scholars believe that in their current form, they are little more than lecture notes. Subsequent to the arrangement of Aristotle's works by Andronicus of Rhodes in the first century BC, a number of his treatises were referred to... | Wikipedia - Aristotelian metaphysics | null | null | null |
But others believe that "meta" referred simply to the work's place in the canonical arrangement of Aristotle's writings, which is at least as old as Andronicus of Rhodes or even Hermippus of Smyrna. In other surviving works of Aristotle, the metaphysical treatises are referred to as "the concerning first philosophy"; ... | Wikipedia - Aristotelian metaphysics | null | null | null |
In the manuscripts, books are referred to by Greek letters. For many scholars, it is customary to refer to the books by their letter names. Book 1 is called Alpha (Α); 2, little alpha (α); 3, Beta (Β); 4, Gamma (Γ); 5, Delta (Δ); 6, Epsilon (Ε); 7, Zeta (Ζ); 8, Eta (Η); 9, Theta (Θ); 10, Iota (Ι); 11, Kappa (Κ); 12, La... | Wikipedia - Aristotelian metaphysics | null | null | null |
Many of Corcoran's articles and reviews are co-authored and many of his single-author publications acknowledge involvement of colleagues and students. Corcoran emphasizes the intensely and essentially personal nature of all genuine knowledge including logical knowledge. Nevertheless, he also stresses the importance of ... | Wikipedia - John Corcoran (logician) | null | null | null |
The achievements of this community are sketched in his 2009 paper "Aristotle's Logic at the University at Buffalo's Department of Philosophy", Ideas y Valores: Revista Colombiana de Filosofía 140 (August 2009) 99–117. A list of his publications, complete through 2000, appears in the 1999 volume of History and Philosoph... | Wikipedia - John Corcoran (logician) | null | null | null |
Many of his logic problems are extensions of classic puzzles. Knights and Knaves involves knights (who always tell the truth) and knaves (who always lie). This is based on a story of two doors and two guards, one who lies and one who tells the truth. One door leads to heaven and one to hell, and the puzzle is to find o... | Wikipedia - Raymond Smullyan | null | null | null |
One way to do this is to ask, "Which door would the other guard say leads to hell?". Unfortunately, this fails, as the liar can answer, "He would say the door to paradise leads to hell," and the truth-teller would answer, "He would say the door to paradise leads to hell." You must point at one of the doors as well as s... | Wikipedia - Raymond Smullyan | null | null | null |
For example, as philosopher Richard Turnbull has explained, you could point at either door and ask, "Will the other guard say this is the door to paradise?" The truth-teller will say "No, " if it is in fact the door to paradise, as will the liar. So you pick that door. | Wikipedia - Raymond Smullyan | null | null | null |
The truth-teller will answer "Yes," if it is the door to Hell, as will the liar, so you pick the other door. Note also that we are not told anything about the goals of either guard: for all we know, the liar may want to help us and the truth-teller not help us, or both are indifferent, so there's no reason to think eit... | Wikipedia - Raymond Smullyan | null | null | null |
This idea was famously used in the 1986 film Labyrinth. In more complex puzzles, he introduces characters who may lie or tell the truth (referred to as "normals"), and furthermore instead of answering "yes" or "no", use words which mean "yes" or "no", but the reader does not know which word means which. | Wikipedia - Raymond Smullyan | null | null | null |
The puzzle known as "the hardest logic puzzle ever" is based on these characters and themes. In his Transylvania puzzles, half of the inhabitants are insane, and believe only false things, whereas the other half are sane and believe only true things. In addition, humans always tell the truth, and vampires always lie. | Wikipedia - Raymond Smullyan | null | null | null |
For example, an insane vampire will believe a false thing (2 + 2 is not 4) but will then lie about it, and say that it is false. A sane vampire knows 2 + 2 is 4, but will lie and say it is not. And mutatis mutandis for humans. | Wikipedia - Raymond Smullyan | null | null | null |
Thus everything said by a sane human or an insane vampire is true, while everything said by an insane human or a sane vampire is false. His book Forever Undecided popularizes Gödel's incompleteness theorems by phrasing them in terms of reasoners and their beliefs, rather than formal systems and what can be proved in th... | Wikipedia - Raymond Smullyan | null | null | null |
The equivalent theorem is that for any formal system S, there exists a mathematical statement that can be interpreted as "This statement is not provable in formal system S". If the system S is consistent, neither the statement nor its opposite will be provable in it. See also Doxastic logic. | Wikipedia - Raymond Smullyan | null | null | null |
Inspector Craig is a frequent character in Smullyan's "puzzle-novellas." He is generally called into a scene of a crime that has a solution that is mathematical in nature. Then, through a series of increasingly harder challenges, he (and the reader) begin to understand the principles in question. | Wikipedia - Raymond Smullyan | null | null | null |
Finally the novella culminates in Inspector Craig (and the reader) solving the crime, utilizing the mathematical and logical principles learned. Inspector Craig generally does not learn the formal theory in question, and Smullyan usually reserves a few chapters after the Inspector Craig adventure to illuminate the anal... | Wikipedia - Raymond Smullyan | null | null | null |
Apart from writing about and teaching logic, Smullyan released a recording of his favorite baroque keyboard and classical piano pieces by composers such as Bach, Scarlatti, and Schubert. Some recordings are available on the Piano Society website, along with the video "Rambles, Reflections, Music and Readings". He has a... | Wikipedia - Raymond Smullyan | null | null | null |
Many of the Rehabilitation Engineering professionals join multidisciplinary scientific and technical associations with a common interest in the field of Assistive Technology and Accessibility. Examples are RESNA - Rehabilitation Engineering and Assistive Technology Society of North America, RESJA - Rehabilitation Engin... | Wikipedia - Rehabilitation engineering | null | null | null |
Many of the Saudi winners of KFUPM Olympiad were selected later on to represent Saudi Arabia in the International Mathematics Olympiad (IMO). This table lists the winners in ten editions of the competition. KFUPM often offers the winners admission after secondary school graduation. | Wikipedia - KFUPM mathematics olympiad | null | null | null |
Many of the ab initio quantum chemistry methods use perturbation theory directly or are closely related methods. Implicit perturbation theory works with the complete Hamiltonian from the very beginning and never specifies a perturbation operator as such. Møller–Plesset perturbation theory uses the difference between th... | Wikipedia - Perturbation theory | null | null | null |
The first-order energy is the Hartree–Fock energy and electron correlation is included at second-order or higher. Calculations to second, third or fourth order are very common and the code is included in most ab initio quantum chemistry programs. A related but more accurate method is the coupled cluster method. | Wikipedia - Perturbation theory | null | null | null |
Many of the appearances of π in the formulae of mathematics and the sciences have to do with its close relationship with geometry. However, π also appears in many natural situations having apparently nothing to do with geometry. In many applications, it plays a distinguished role as an eigenvalue. | Wikipedia - Archimedes' constant | null | null | null |
For example, an idealized vibrating string can be modelled as the graph of a function f on the unit interval , with fixed ends f(0) = f(1) = 0. The modes of vibration of the string are solutions of the differential equation f ″ ( x ) + λ f ( x ) = 0 {\displaystyle f''(x)+\lambda f(x)=0} , or f ″ ( t ) = − λ f ( x ) {\d... | Wikipedia - Archimedes' constant | null | null | null |
It must be positive, since the operator is negative definite, so it is convenient to write λ = ν2, where ν > 0 is called the wavenumber. Then f(x) = sin(π x) satisfies the boundary conditions and the differential equation with ν = π.The value π is, in fact, the least such value of the wavenumber, and is associated with... | Wikipedia - Archimedes' constant | null | null | null |
Many of the balls have not had their discovery site recorded and most are found as a result of agricultural activity. Five were found at the Neolithic settlement of Skara Brae and one at the Dunadd hillfort. The distribution of the balls is similar to that of mace-heads, which were both weapons and prestige objects use... | Wikipedia - Carved stone balls | null | null | null |
Random finds are only likely to have been picked up and entered a collection if they were aesthetically appealing. Damaged and plain balls were less likely to find a market than decorated examples so some more decorated examples might be fraudulent. Balls of plain sandstone with the facets from shaping still clearly vi... | Wikipedia - Carved stone balls | null | null | null |
A significant number have already been found here and are known from other southern Scottish Iron Age sites. They may date from the fourth to third centuries BC. These balls are not ornamented and do not have knobs.In 2013, archaeologists discovered a carved stone ball at Ness of Brodgar, a rare find of such an object ... | Wikipedia - Carved stone balls | null | null | null |
Many of the biogeochemical processes in the bathypelagic region are dependent upon the input of organic matter from the overlying epipelagic and mesopelagic zones. This organic material, sometimes called marine snow, sinks in the water column or is transported within downward convected water masses such as the Thermoha... | Wikipedia - Midnight zone | null | null | null |
Our understanding of these biogeochemical processes has historically been limited due to the difficulty and cost of collecting samples from these ocean depths. Other technological challenges, such as measuring microbial activity under the pressure conditions experienced in the bathypelagic zone, have also restricted ou... | Wikipedia - Midnight zone | null | null | null |
One of the major areas of current research is focused on understanding carbon remineralization rates in the region. Prior studies have struggled to quantify the rates at which prokaryotes in this region remineralize carbon because previously developed techniques may not be adequate for this region, and indicate reminer... | Wikipedia - Midnight zone | null | null | null |
Many of the biological and behavioural activities of plants, animals (including birds and amphibians), insects, and microorganisms are either adversely affected by light pollution at night or can only function effectively either during or as the consequence of nightly darkness. Such activities include foraging, breedin... | Wikipedia - Scotobiology | null | null | null |
These include breeding behavior in a range of animals, the control of flowering and the induction of winter dormancy in many plants, and the operational control of the human immune system. In many of these biological processes the critical point is the length of the dark period rather than that of the light. For exampl... | Wikipedia - Scotobiology | null | null | null |
That is to say, plants do not measure the length of the light period, but of the dark period. One consequence of artificial light pollution is that even brief periods of relatively bright light during the night may prevent plants or animals (including humans) from measuring the length of the dark period, and therefore ... | Wikipedia - Scotobiology | null | null | null |
In discussing scotobiology, it is important to remember that darkness (the absence of light) is seldom absolute. An important aspect of any scotobiological phenomenon is the level and quality (wavelength) of light that is below the threshold of detection for that phenomenon and in any specific organism. This important ... | Wikipedia - Scotobiology | null | null | null |
There are substantial levels of natural light pollution at night, of which moonlight is usually the strongest. For example, plants that rely on night length to program their behaviour have the capacity to ignore full moonlight during an otherwise dark night. If this ability had not evolved, plants would not be able to ... | Wikipedia - Scotobiology | null | null | null |
Many of the conserved, essential and abundant ncRNAs are involved in translation. Ribonucleoprotein (RNP) particles called ribosomes are the 'factories' where translation takes place in the cell. The ribosome consists of more than 60% ribosomal RNA; these are made up of 3 ncRNAs in prokaryotes and 4 ncRNAs in eukaryote... | Wikipedia - Non-coding RNAs | null | null | null |
Another set of ncRNAs, Transfer RNAs, form an 'adaptor molecule' between mRNA and protein. The H/ACA box and C/D box snoRNAs are ncRNAs found in archaea and eukaryotes. RNase MRP is restricted to eukaryotes. | Wikipedia - Non-coding RNAs | null | null | null |
Both groups of ncRNA are involved in the maturation of rRNA. The snoRNAs guide covalent modifications of rRNA, tRNA and snRNAs; RNase MRP cleaves the internal transcribed spacer 1 between 18S and 5.8S rRNAs. The ubiquitous ncRNA, RNase P, is an evolutionary relative of RNase MRP. | Wikipedia - Non-coding RNAs | null | null | null |
RNase P matures tRNA sequences by generating mature 5'-ends of tRNAs through cleaving the 5'-leader elements of precursor-tRNAs. Another ubiquitous RNP called SRP recognizes and transports specific nascent proteins to the endoplasmic reticulum in eukaryotes and the plasma membrane in prokaryotes. In bacteria, Transfer-... | Wikipedia - Non-coding RNAs | null | null | null |
Many of the constants and variables contained within a DCB may be left blank (i.e., these default to zero). The OPEN process results in a merge of the constants and variables specified in the DD JCL statement, and the dataset label for existing magnetic tape and direct-access datasets, into the DCB, replacing the zero ... | Wikipedia - Data Control Block | null | null | null |
Many of the constants known to be periods are also given by integrals of transcendental functions. Kontsevich and Zagier note that there "seems to be no universal rule explaining why certain infinite sums or integrals of transcendental functions are periods". Kontsevich and Zagier conjectured that, if a period is given... | Wikipedia - Ring of periods | null | null | null |
A useful property of algebraic numbers is that equality between two algebraic expressions can be determined algorithmically. The conjecture of Kontsevich and Zagier would imply that equality of periods is also decidable: inequality of computable reals is known recursively enumerable; and conversely if two integrals agr... | Wikipedia - Ring of periods | null | null | null |
Many of the detections to date have been made with a quick reduction package that allows us to find pulsars almost in real time. This is made possible by reducing the spectral and time resolution by a factor of 16, and using a computer cluster, the Arecibo Signal Processor to search for pulsars in the data. This is a n... | Wikipedia - PALFA Survey | null | null | null |
It is expected that, over the next several years, this survey will generate over 1000 Terabytes of data. The data is stored at the Cornell University Center for Advanced Computing. The full-resolution raw data is processed independently by three software pipelines. | Wikipedia - PALFA Survey | null | null | null |
The Cornell University pipeline has conducted standard periodicity search and single-pulse search without doing an acceleration search. It has been run on all WAPP data archived at the Cornell University Center for Advanced Computing and has provided 2.5 million signal candidates. Winnowing of this vast set of candidat... | Wikipedia - PALFA Survey | null | null | null |
The second pipeline is based on PRESTO, a large suite of pulsar search and analysis software developed by Scott Ransom. It employs a Fourier-domain acceleration search technique, which compensates for the loss of detection sensitivity in a traditional periodicity search due to a rapidly changing frequency of the period... | Wikipedia - PALFA Survey | null | null | null |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.