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disturbing scenes, which triggered discussions about ethical implications of technologies developed by Black Forest Labs. After the release of the model, social media platform X was flooded with Flux-generated images. Black Forest Labs has not provided exact details of the data used to train the model. Ars Technica sus...	{ "page_id": 78378498, "title": "Flux (text-to-image model)" }
The deferred measurement principle is a result in quantum computing which states that delaying measurements until the end of a quantum computation doesn't affect the probability distribution of outcomes. A consequence of the deferred measurement principle is that measuring commutes with conditioning. The choice of whet...	{ "page_id": 42726919, "title": "Deferred measurement principle" }
Organic geochemistry is the study of the impacts and processes that organisms have had on the Earth. It is mainly concerned with the composition and mode of origin of organic matter in rocks and in bodies of water. The study of organic geochemistry is traced to the work of Alfred E. Treibs, "the father of organic geoch...	{ "page_id": 456204, "title": "Organic geochemistry" }
provide insight into the Earth's carbon cycle and geological processes. Geochemists are able to discern the composition of petroleum deposits by examining the ratio of carbon isotopes and comparing this ratio to known values for carbon based structures of which the petroleum could be composed. ==== Coal ==== Vast knowl...	{ "page_id": 456204, "title": "Organic geochemistry" }
animal manure, in combination with general municipal and sewage waste management, has changed many physical properties of the agricultural soil involved and the surrounding soils. Organic geochemistry is also relevant to aqueous environments. Pollutants, their metabolites, and how both enter bodies of water are of part...	{ "page_id": 456204, "title": "Organic geochemistry" }
The United States biological weapons program officially began in spring 1943 on orders from U.S. President Franklin D. Roosevelt. Research continued following World War II as the U.S. built up a large stockpile of biological agents and weapons. Over the course of its 27-year history, the program weaponized and stockpil...	{ "page_id": 10548751, "title": "United States biological weapons program" }
such a program would not be "profitable" for the U.S. Japan's Shirō Ishii began promoting biological weapons during the 1920s and toured biological research facilities worldwide, including in the United States. Though Ishii concluded that the U.S. was developing a bio-weapons program, he was incorrect. In fact, Ishii c...	{ "page_id": 10548751, "title": "United States biological weapons program" }
committee by the Division of Medical Sciences of the National Research Council to examine one phase of the matter. In response the NAS formed a committee, the War Bureau of Consultants (WBC), which issued a report on the subject in February 1942. The report, among other items, recommended the research and development o...	{ "page_id": 10548751, "title": "United States biological weapons program" }
in biological weapons". === Cold War (1947–1969) === Following World War II, the United States biological warfare program progressed into an effective, military-driven research and production program, covered in controversy and secrecy. Production of U.S. biological warfare agents went from "factory-level to laboratory...	{ "page_id": 10548751, "title": "United States biological weapons program" }
retained only within the continental limits of the United States." Another substantive expansion phase was during the Kennedy-Johnson years, after McNamara initiated Project 112 as a comprehensive initiative, starting in 1961. Despite an increase in testing, the readiness for biological warfare remained limited after t...	{ "page_id": 10548751, "title": "United States biological weapons program" }
issued a warning against the development of biological weapons during the Cold War. In 1945, Rosebury left Camp Detrick during a period of time when scientists could publish the results of their research. Rosebury published Peace or Pestilence? in 1949, which explained his views on why biological weapons should be bann...	{ "page_id": 10548751, "title": "United States biological weapons program" }
to those that would incapacitate. In 1964, research programs studied Enterotoxin type B, which can cause food poisoning. New research initiatives also included prophylaxis, the preventive treatment of diseases. Pathogens studied included the biological agents causing a myriad of diseases such as anthrax, glanders, bruc...	{ "page_id": 10548751, "title": "United States biological weapons program" }
1969, in a speech from Fort Detrick. The statement officially ended all U.S. offensive biological weapons programs. Nixon noted that biological weapons were unreliable and stated: The United States shall renounce the use of lethal biological agents and weapons, and all other methods of biological warfare. The United St...	{ "page_id": 10548751, "title": "United States biological weapons program" }
a ban on bacteriological warfare. The Geneva Protocol had encountered opposition in the U.S. Senate, in part due to strong lobbying against it by the Chemical Warfare Service, and it was never brought to the floor for a vote when originally introduced. Regardless, on June 8, 1943, President Roosevelt affirmed a no-firs...	{ "page_id": 10548751, "title": "United States biological weapons program" }
to be used, the U.S. program conducted research into the weaponization of more than 20 other agents. They included: smallpox, EEE and WEE, AHF, Hantavirus, BHF, Lassa fever, melioidosis, plague, yellow fever, psittacosis, typhus, dengue fever, Rift Valley fever (RVF), CHIKV, late blight of potato, rinderpest, Newcastle...	{ "page_id": 10548751, "title": "United States biological weapons program" }
M143 bomblet, similar to the chemical M139 bomblet. The experimental Flettner rotor bomblet was also developed during this time period. The Flettner rotor was called, "probably one of the better devices for disseminating microorganisms", by William C. Patrick III. == Alleged uses == === Korean War === In 1952, during t...	{ "page_id": 10548751, "title": "United States biological weapons program" }
War International History Project at the Woodrow Wilson Center in Washington released a cache of Soviet and Chinese documents that claimed to have revealed that the biowarfare allegation was an elaborate disinformation campaign by the communists. In addition, a Japanese journalist claims to have seen similar evidence o...	{ "page_id": 10548751, "title": "United States biological weapons program" }
measures be taken against "bacteria" dropped by UN aircraft, apparently in the area around Sariwon. The report stated that "three persons ... became suddenly feverish", presumably in their unit. Their nervous systems were said to have become "benumbed". === Cuba === It has been rumored that the U.S. employed biological...	{ "page_id": 10548751, "title": "United States biological weapons program" }
linking these incidents to biological warfare has not been confirmed, however, according to Kieth Bolender, a French scientist analyzing the situation concluded that it was not possible that the outbreak had occurred naturally. Accusations have continued to come out of Havana alleging continued U.S. use of bio-weapons ...	{ "page_id": 10548751, "title": "United States biological weapons program" }
of biological warfare which aims to use insects as weapon, either directly or through their potential to act as vectors. During the 1950s the United States conducted a series of field tests using entomological weapons. Operation Big Itch, in 1954, was designed to test munitions loaded with uninfected fleas (Xenopsylla ...	{ "page_id": 10548751, "title": "United States biological weapons program" }
and compensation made by veterans who believe they got sick as a result of the tests. The U.S. military for decades remained silent about "Project 112" and its victims, a slew of tests overseen by the Army's Deseret Test Center in Salt Lake City. Project 112 starting in the 1960s tested chemical and biological agents, ...	{ "page_id": 10548751, "title": "United States biological weapons program" }
laboratory personnel disguised as passengers spraying harmless bacteria in Washington National Airport. A jet aircraft released material over Victoria, Texas, that was monitored in the Florida Keys. === GAO Report === In February 2008, the Government Accountability Office (GAO) released report GAO-08-366 titled, "Chemi...	{ "page_id": 10548751, "title": "United States biological weapons program" }
biological weapons research because the BWC contains no provisions for monitoring or enforcement. The treaty, essentially, is a gentlemen's agreement amongst members backed by the long-prevailing thought that biological warfare should not be used in battle. After Nixon declared an end to the U.S. bio-weapons program, d...	{ "page_id": 10548751, "title": "United States biological weapons program" }
invasion of Ukraine, the Russians claimed that they had come across "US military-run biolabs in Ukraine" supposedly developing biological weapons. The Ukraine biolabs conspiracy theory was rejected as without evidence by the US, Ukraine, the United Nations, Russian scientists, and Reuters. who stated the labs are perfo...	{ "page_id": 10548751, "title": "United States biological weapons program" }
in the Korean War 2001 anthrax attacks == References == === Further reading === Cirincione, Joseph, et al. Deadly Arsenals: Nuclear, Biological, and Chemical Threats, (Google Books), Carnegie Endowment, 2005, ISBN 087003216X. Croddy, Eric and Wirtz, James J. Weapons of Mass Destruction: An Encyclopedia of Worldwide Pol...	{ "page_id": 10548751, "title": "United States biological weapons program" }
Structured prediction or structured output learning is an umbrella term for supervised machine learning techniques that involves predicting structured objects, rather than discrete or real values. Similar to commonly used supervised learning techniques, structured prediction models are typically trained by means of obs...	{ "page_id": 27260435, "title": "Structured prediction" }
This fact can be exploited in a sequence model such as a hidden Markov model or conditional random field that predicts the entire tag sequence for a sentence (rather than just individual tags) via the Viterbi algorithm. == Techniques == Probabilistic graphical models form a large class of structured prediction models. ...	{ "page_id": 27260435, "title": "Structured prediction" }
, ϕ ( x , y ) ) {\displaystyle {\hat {y}}={\operatorname {arg\,max} }\,\{y\in GEN(x)\}\,(w^{T},\phi (x,y))} Update w {\displaystyle w} (from y ^ {\displaystyle {\hat {y}}} towards t {\displaystyle t} ): w = w + c ( − ϕ ( x , y ^ ) + ϕ ( x , t ) ) {\displaystyle w=w+c(-\phi (x,{\hat {y}})+\phi (x,t))} , where c {\displa...	{ "page_id": 27260435, "title": "Structured prediction" }
Process analytical chemistry (PAC) is the application of analytical chemistry with specialized techniques, algorithms, and sampling equipment for solving problems related to chemical processes. It is a specialized form of analytical chemistry used for process manufacturing similar to process analytical technology (PAT)...	{ "page_id": 27915795, "title": "Process analytical chemistry" }
1996. Gregory, C. H. (Team Leader); Appleton, H. B.; Lowes, A. P.; Whalen, F. C. Instrumentation & Control in the German Chemical Industry. British Intelligence Operations Subcommittee Report 1007, 12 June 1946 (per discussion with Terry McMahon). Workman Jr, Jerome J.; Koch, Mel; Lavine, Barry; Chrisman, Ray (2009). "...	{ "page_id": 27915795, "title": "Process analytical chemistry" }
The tonograph (Italian: tonografo) is a device invented by Italian scientist Luca de Samuele Cagnazzi (1764-1852) and presented at the Terza riunione degli scienziati italiani (the "Third Meeting of Italian Scientists"), held in Florence in September 1841. The original device was donated by its inventor Cagnazzi during...	{ "page_id": 63108627, "title": "Tonograph" }
Inside the cylinder there is a piston whose position is regulated by a thin rod and, as the position of the piston changes, the length of the cylinder also changes. As the plunger (and therefore the rod) changes, the instrument will generate a different sound. A graduated scale makes it possible to "measure" the intona...	{ "page_id": 63108627, "title": "Tonograph" }
are intrinsically different. Majeri himself replied to Gazzeri's objection by explaining that sound is described by three factors, namely tone, intensity and timbre. The tone depends on the sound's frequency, the intensity is the "strength" of a sound, while the timbre depends on the material of the "sounding body" (It...	{ "page_id": 63108627, "title": "Tonograph" }
the classical era. Cagnazzi faces the impossibility (with some exceptions) of faithfully reconstructing the tones and inflections of the voice that the Ancient Greeks and the Romans used in their survived works. The same inventor, in the first part of his essay Tonografia escogitata (1841) made some acute observations ...	{ "page_id": 63108627, "title": "Tonograph" }
couldn't reach it. == See also == Luca de Samuele Cagnazzi Declamation Acoustics Physics == References == == Bibliography == Atti della Terza della Riunione degli Scienziati italiani tenuta in Firenze nel settembre del 1841. Florence: Galileiana. 1841. pp. 205–210. Annali di fisica, chimica e matematiche col bullettino...	{ "page_id": 63108627, "title": "Tonograph" }
Quarterly Reviews of Biophysics is a peer-reviewed scientific journal on biophysics, published by Cambridge University Press. It was established in 1968. The current chief editor is Bengt Nordén. According to the Journal Citation Reports, the journal has a 2020 impact factor of 5.318, ranking it 10th out of 71 journals...	{ "page_id": 71104024, "title": "Quarterly Reviews of Biophysics" }
Gallium selenide may refer to: Gallium(II) selenide Gallium(III) selenide	{ "page_id": 20051480, "title": "Gallium selenide" }
Post Irradiation Examination (PIE) is the study of used nuclear materials such as nuclear fuel. It has several purposes. It is known that by examination of used fuel that the failure modes which occur during normal use (and the manner in which the fuel will behave during an accident) can be studied. In addition informa...	{ "page_id": 10810905, "title": "Post Irradiation Examination" }
are common. In addition to the effects of radiation and the fission products on materials, scientists also need to consider the temperature of materials in a reactor, and in particular, the fuel. Too high fuel temperatures can compromise the fuel, and therefore it is important to control the temperature in order to con...	{ "page_id": 10810905, "title": "Post Irradiation Examination" }
The Davies equation is an empirical extension of Debye–Hückel theory which can be used to calculate activity coefficients of electrolyte solutions at relatively high concentrations at 25 °C. The equation, originally published in 1938, was refined by fitting to experimental data. The final form of the equation gives the...	{ "page_id": 22476314, "title": "Davies equation" }
A flashover is the near-simultaneous ignition of most of the directly exposed combustible material in an enclosed area. When certain organic materials are heated, they undergo thermal decomposition and release flammable gases. Flashover occurs when the majority of the exposed surfaces in a space are heated to their aut...	{ "page_id": 521753, "title": "Flashover" }
smoke cloud ignites after congregating outside of its room of origin. This results in a volatile situation, and if the ignition occurs at the ideal mixture, the result can be a violent smoke gas explosion. This is referred to as smoke explosion or fire gas ignition depending on the severity of the combustion process. A...	{ "page_id": 521753, "title": "Flashover" }
compartment, so there is no shortage of oxygen in the room. Firefighters memorize a chant to help remember these during training: "Thick dark smoke, high heat, rollover, free burning." The colour of the smoke is often considered as well, but there is no connection between the colour of the smoke and the risk of flashov...	{ "page_id": 521753, "title": "Flashover" }
As described by the third of Newton's laws of motion of classical mechanics, all forces occur in pairs such that if one object exerts a force on another object, then the second object exerts an equal and opposite reaction force on the first. The third law is also more generally stated as: "To every action there is alwa...	{ "page_id": 1111581, "title": "Reaction (physics)" }
Sun because the Sun exerts a gravitational pull that acts as a centripetal force, holding the Earth to it, which would otherwise go shooting off into space. If the Sun's pull is considered an action, then Earth simultaneously exerts a reaction as a gravitational pull on the Sun. Earth's pull has the same amplitude as t...	{ "page_id": 1111581, "title": "Reaction (physics)" }
gravitational force by earth on object (downward) F2. gravitational force by object on earth (upward) F3. force by support on object (upward) F4. force by object on support (downward) Forces F1 and F2 are equal, due to Newton's third law; the same is true for forces F3 and F4. Forces F1 and F3 are equal if and only if ...	{ "page_id": 1111581, "title": "Reaction (physics)" }
force by the player on the ball is considered the 'action' and the force by the ball on the player, the 'reaction'. But physically, the situation is symmetric. The forces on ball and player are both explained by their nearness, which results in a pair of contact forces (ultimately due to electric repulsion). That this ...	{ "page_id": 1111581, "title": "Reaction (physics)" }
an accelerating elevator. The case of any number of forces acting on the same object is covered by considering the sum of all forces. A possible cause of this problem is that the third law is often stated in an abbreviated form: For every action there is an equal and opposite reaction, without the details, namely that ...	{ "page_id": 1111581, "title": "Reaction (physics)" }
Transfer cells are specialized parenchyma cells that have an increased surface area, due to infoldings of the plasma membrane. They facilitate the transport of sugars from a sugar source, mainly mature leaves, to a sugar sink, often developing leaves or fruits. They are found in nectaries of flowers and some carnivorou...	{ "page_id": 4453918, "title": "Transfer cell" }
The Beta-globin co-transcriptional cleavage ribozyme (CotC ribozyme) was proposed to be an RNA enzyme known as a ribozyme. Transcription termination of RNA polymerase II transcripts is proposed to occur by a two-stage process. The first stage involves pre-termination cleavage (PTC) of the nascent transcript downstream ...	{ "page_id": 13628958, "title": "Beta-globin co-transcriptional cleavage ribozyme" }
The Viehland–Mason theory is a two-temperature theory for charged and neutral atoms, which explains how trace ions can have a substantially different temperature than dilute gas atoms. It is one of any of a number of kinetic theories of the transport of trace amounts of molecular ions through neutral gases under the in...	{ "page_id": 9958944, "title": "Viehland–Mason theory" }
The molecular formula C25H28N2O2 may refer to: Diphenpipenol JNJ-20788560	{ "page_id": 60880417, "title": "C25H28N2O2" }
Nocturnality is a behavior in some non-human animals characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnal meaning the opposite. Nocturnal creatures generally have highly developed senses of hearing, smell, and specially adapted eyesight. Some an...	{ "page_id": 63011, "title": "Nocturnality" }
smell and more astute auditory systems. In a recent study, recently extinct elephant birds and modern day nocturnal kiwi bird skulls were examined to recreate their likely brain and skull formation. They indicated that olfactory bulbs were much larger in comparison to their optic lobes, indicating they both have a comm...	{ "page_id": 63011, "title": "Nocturnality" }
or night, they prefer to hunt at night because many of their prey species (zebra, antelope, impala, wildebeest, etc.) have poor night vision. Many species of small rodents, such as the Large Japanese Field Mouse, are active at night because most of the dozen or so birds of prey that hunt them are diurnal. There are man...	{ "page_id": 63011, "title": "Nocturnality" }
bats, another creature of the night. Climate change has led to an increasing number of diurnal species to push their activity patterns closer towards crepuscular or fully nocturnal behavior. This adaptive measure allows species to avoid the day's heat, without having to leave that particular habitat. == Human disturban...	{ "page_id": 63011, "title": "Nocturnality" }
eggs on, as there is less cover against predators. Additionally, baby sea turtles that hatch from eggs on artificially lit beaches often get lost, heading towards the light sources as opposed to the ocean. ==== Rhythmic behaviors ==== Rhythmic behaviors are affected by light pollution both seasonally and daily patterns...	{ "page_id": 63011, "title": "Nocturnality" }
=== Spatial disturbance === The increasing amount of habitat destruction worldwide as a result of human expansion has given both advantages and disadvantages to different nocturnal animals. As a result of peak human activity in the daytime, more species are likely to be active at night in order to avoid the new disturb...	{ "page_id": 63011, "title": "Nocturnality" }
The BSSN formalism (Baumgarte, Shapiro, Shibata, Nakamura formalism) is a formalism of general relativity that was developed by Thomas W. Baumgarte, Stuart L. Shapiro, Masaru Shibata and Takashi Nakamura between 1987 and 1999. It is a modification of the ADM formalism developed during the 1950s. The ADM formalism is a ...	{ "page_id": 26998311, "title": "BSSN formalism" }
In chemistry, colligative properties are those properties of solutions that depend on the ratio of the number of solute particles to the number of solvent particles in a solution, and not on the nature of the chemical species present. The number ratio can be related to the various units for concentration of a solution ...	{ "page_id": 456234, "title": "Colligative properties" }
to determinations of relative molar masses, both for small molecules and for polymers which cannot be studied by other means. Alternatively, measurements for ionized solutes can lead to an estimation of the percentage of dissociation taking place. Colligative properties are studied mostly for dilute solutions, whose be...	{ "page_id": 456234, "title": "Colligative properties" }
) = p A ⋆ x B {\displaystyle \Delta p=p_{\rm {A}}^{\star }-p=p_{\rm {A}}^{\star }(1-x_{\rm {A}})=p_{\rm {A}}^{\star }x_{\rm {B}}} , which is proportional to the mole fraction of solute. If the solute dissociates in solution, then the number of moles of solute is increased by the van 't Hoff factor i {\displaystyle i} ,...	{ "page_id": 456234, "title": "Colligative properties" }
since very few solutes dissolve appreciably in solid solvents. === Boiling point elevation (ebullioscopy) === The boiling point of a liquid at a given external pressure is the temperature ( T b {\displaystyle T_{\rm {b}}} ) at which the vapor pressure of the liquid equals the external pressure. The normal boiling point...	{ "page_id": 456234, "title": "Colligative properties" }
t m ) , {\displaystyle \mu _{A}(T_{b})=\mu _{A}^{\star }(T_{b})+RT\ln x_{A}\ =\mu _{A}^{\star }(g,1\,\mathrm {atm} ),} The asterisks indicate pure phases. This leads to the result K b = R M T b 2 / Δ H v a p {\displaystyle K_{b}=RMT_{b}^{2}/\Delta H_{\mathrm {vap} }} , where R is the molar gas constant, M is the solven...	{ "page_id": 456234, "title": "Colligative properties" }
equality of chemical potentials permits the evaluation of the cryoscopic constant as K f = R M T f 2 / Δ f u s H {\displaystyle K_{f}=RMT_{f}^{2}/\Delta _{\mathrm {fus} }H} , where ΔfusH is the solvent molar enthalpy of fusion. == Osmotic pressure == The osmotic pressure of a solution is the difference in pressure betw...	{ "page_id": 456234, "title": "Colligative properties" }
i {\displaystyle \Pi ={\frac {nRTi}{V}}=cRTi} The osmotic pressure is proportional to the concentration of solute particles ci and is therefore a colligative property. As with the other colligative properties, this equation is a consequence of the equality of solvent chemical potentials of the two phases in equilibrium...	{ "page_id": 456234, "title": "Colligative properties" }
Wylie Dufresne is an American chef. He was previously the owner of Du's Donuts and the former chef and owner of the wd~50 and Alder restaurants in Manhattan. He now owns Stretch Pizza on 24th Street and Park in Manhattan. Dufresne is a leading American proponent of molecular gastronomy, the movement to incorporate scie...	{ "page_id": 5305904, "title": "Wylie Dufresne" }
the first Red Guide for North America, and was nominated for Best Chef New York by the James Beard Foundation. His signature preparations include Pickled Beef Tongue with Fried Mayonnaise and Carrot-Coconut Sunnyside-Up. In 2006, Dufresne lost to Mario Batali on Iron Chef America. In 2007, he began making appearances a...	{ "page_id": 5305904, "title": "Wylie Dufresne" }
A variable star is a star whose brightness as seen from Earth (its apparent magnitude) changes systematically with time. This variation may be caused by a change in emitted light or by something partly blocking the light, so variable stars are classified as either: Intrinsic variables, whose luminosity actually changes...	{ "page_id": 63025, "title": "Variable star" }
1784. Chi Cygni was identified in 1686 by G. Kirch, then R Hydrae in 1704 by G. D. Maraldi. By 1786, ten variable stars were known. John Goodricke himself discovered Delta Cephei and Beta Lyrae. Since 1850, the number of known variable stars has increased rapidly, especially after 1890 when it became possible to identi...	{ "page_id": 63025, "title": "Variable star" }
the magnitudes are known and constant. By estimating the variable's magnitude and noting the time of observation a visual lightcurve can be constructed. The American Association of Variable Star Observers collects such observations from participants around the world and shares the data with the scientific community. Fr...	{ "page_id": 63025, "title": "Variable star" }
changes that occur in a variable star. For example, evidence for a pulsating star is found in its shifting spectrum because its surface periodically moves toward and away from us, with the same frequency as its changing brightness. About two-thirds of all variable stars appear to be pulsating. In the 1930s astronomer A...	{ "page_id": 63025, "title": "Variable star" }
Lyrae. Later discoveries used letters AA through AZ, BB through BZ, and up to QQ through QZ (with J omitted). Once those 334 combinations are exhausted, variables are numbered in order of discovery, starting with the prefixed V335 onwards. == Classification == Variable stars may be either intrinsic or extrinsic. Intrin...	{ "page_id": 63025, "title": "Variable star" }
one part of the star expands while another part shrinks. Depending on the type of pulsation and its location within the star, there is a natural or fundamental frequency which determines the period of the star. Stars may also pulsate in a harmonic or overtone which is a higher frequency, corresponding to a shorter peri...	{ "page_id": 63025, "title": "Variable star" }
is believed to account for cepheid-like pulsations. Each of the subgroups on the instability strip has a fixed relationship between period and absolute magnitude, as well as a relation between period and mean density of the star. The period-luminosity relationship was first established for Delta Cepheids by Henrietta L...	{ "page_id": 63025, "title": "Variable star" }
to Population II, but of lower mass than type II Cepheids. Due to their common occurrence in globular clusters, they are occasionally referred to as cluster Cepheids. They also have a well established period-luminosity relationship, and so are also useful as distance indicators. These A-type stars vary by about 0.2–2 m...	{ "page_id": 63025, "title": "Variable star" }
in luminosity. Mira itself, also known as Omicron Ceti (ο Cet), varies in brightness from almost 2nd magnitude to as faint as 10th magnitude with a period of roughly 332 days. The very large visual amplitudes are mainly due to the shifting of energy output between visual and infra-red as the temperature of the star cha...	{ "page_id": 63025, "title": "Variable star" }
change in luminosity). They are at their brightest during minimum contraction. Many stars of this kind exhibits multiple pulsation periods. ==== Slowly pulsating B-type stars ==== Slowly pulsating B (SPB) stars are hot main-sequence stars slightly less luminous than the Beta Cephei stars, with longer periods and larger...	{ "page_id": 63025, "title": "Variable star" }
Their periods range from several days to several weeks, and their amplitudes of variation are typically of the order of 0.1 magnitudes. The light changes, which often seem irregular, are caused by the superposition of many oscillations with close periods. Deneb, in the constellation of Cygnus is the prototype of this c...	{ "page_id": 63025, "title": "Variable star" }
is a luminous yellow supergiant with pulsations shorter than a day. They are thought to have evolved beyond a red supergiant phase, but the mechanism for the pulsations is unknown. The class was named in 2020 through analysis of TESS observations. === Eruptive variable stars === Eruptive variable stars show irregular o...	{ "page_id": 63025, "title": "Variable star" }
mass loss is fairly common among giants and supergiants. ===== Luminous blue variables ===== Also known as the S Doradus variables, the most luminous stars known belong to this class. Examples include the hypergiants η Carinae and P Cygni. They have permanent high mass loss, but at intervals of years internal pulsation...	{ "page_id": 63025, "title": "Variable star" }
around the star. They exhibit broad emission line spectra with helium, nitrogen, carbon and oxygen lines. Variations in some stars appear to be stochastic while others show multiple periods. ==== Gamma Cassiopeiae variables ==== Gamma Cassiopeiae (γ Cas) variables are non-supergiant fast-rotating B class emission line-...	{ "page_id": 63025, "title": "Variable star" }
enormous energy quantity. The outer layers of these stars are blown away at speeds of many thousands of kilometers per second. The expelled matter may form nebulae called supernova remnants. A well-known example of such a nebula is the Crab Nebula, left over from a supernova that was observed in China and elsewhere in ...	{ "page_id": 63025, "title": "Variable star" }
They form in close binary systems, one component being a white dwarf accreting matter from the other ordinary star component, and may recur over periods of decades to centuries or millennia. Novae are categorised as fast, slow or very slow, depending on the behaviour of their light curve. Several naked eye novae have b...	{ "page_id": 63025, "title": "Variable star" }
formation of an accretion disk. ==== AM Herculis variables ==== In these cataclysmic variables, the white dwarf's magnetic field is so strong that it synchronizes the white dwarf's spin period with the binary orbital period. Instead of forming an accretion disk, the accretion flow is channeled along the white dwarf's m...	{ "page_id": 63025, "title": "Variable star" }
surface of the star is not uniformly bright, but has darker and brighter areas (like the sun's solar spots). The star's chromosphere too may vary in brightness. As the star rotates we observe brightness variations of a few tenths of magnitudes. ===== FK Comae Berenices variables ===== These stars rotate extremely rapid...	{ "page_id": 63025, "title": "Variable star" }
together form a binary star. When seen from certain angles, one star may eclipse the other, causing a reduction in brightness. One of the most famous eclipsing binaries is Algol, or Beta Persei (β Per). ==== Algol variables ==== Algol variables undergo eclipses with one or two minima separated by periods of nearly cons...	{ "page_id": 63025, "title": "Variable star" }
List of variable stars Stellar pulsation == References == == Bibliography == Eddington, A.S.; Plakidis, S. (1929). "Irregularities of Period of Long Period Variable Stars". Monthly Notices of the Royal Astronomical Society. 90 (1). London, UK: 65–71. doi:10.1093/mnras/90.1.65. Retrieved February 17, 2023. == External l...	{ "page_id": 63025, "title": "Variable star" }
The hoop conjecture, proposed by Kip Thorne in 1972, states that an imploding object forms a black hole when, and only when, a circular hoop with a specific critical circumference could be placed around the object and rotated about its diameter. In simpler terms, the entirety of the object's mass must be compressed to ...	{ "page_id": 3339824, "title": "Hoop conjecture" }
to Thorn's circular hoops. == See also == General relativity Bounding sphere Black hole stability conjecture == References == Thorne, Kip, Black Holes and Time Warps: Einstein's Outrageous Legacy, W. W. Norton & Company; Reprint edition, January 1, 1995. ISBN 0-393-31276-3.	{ "page_id": 3339824, "title": "Hoop conjecture" }
The molecular formula C8H10O4 (molar mass: 170.16 g/mol, exact mass: 107.0579 u) may refer to: Dihydroxyphenylethylene glycol, a phenolic human metabolic Penicillic acid	{ "page_id": 24605217, "title": "C8H10O4" }
Ghost imaging (also called "coincidence imaging", "two-photon imaging" or "correlated-photon imaging") is a technique that produces an image of an object by combining information from two light detectors: a conventional, multi-pixel detector that does not view the object, and a single-pixel (bucket) detector that does ...	{ "page_id": 18347577, "title": "Ghost imaging" }
'Compressed-Sensing' can be directly utilized to reduce the number of measurements required for image reconstruction in ghost imaging. This technique allows an N pixel image to be produced with far less than N measurements and may have applications in LIDAR and microscopy. === Advances in military research === The U.S....	{ "page_id": 18347577, "title": "Ghost imaging" }
hit a pixel at the back of the empty box, the second light beam will sometimes be blocked by the object and will not reach the bucket detector. A processor receiving a signal from both light detectors only records a pixel of an image when light hits both detectors at the same time. In this way, a silhouette image can b...	{ "page_id": 18347577, "title": "Ghost imaging" }
infrared light === Infrared cameras that combine low-noise with single-photon sensitivity are not readily available. Infrared illumination of a vulnerable target with sparse photons can be combined with a camera counting visible photons through the use of ghost imaging with correlated photons that have significantly di...	{ "page_id": 18347577, "title": "Ghost imaging" }
to quantum imaging advances Army Research Laboratory News DECEMBER 19, 2013. Accessed Feb 2014	{ "page_id": 18347577, "title": "Ghost imaging" }
The Different Forms of Flowers on Plants of the Same Species is a book by Charles Darwin first published in 1877. It is the fifth of his six books devoted solely to the study of plants (excluding The Variation of Animals and Plants Under Domestication). == Context == These writings contributed to Darwin's pursuit of ev...	{ "page_id": 33748539, "title": "The Different Forms of Flowers on Plants of the Same Species" }
heterostyly. == Summary. == In 1883, Alfred Russel Wallace wrote a tribute to Darwin (entitled 'The Debt of Science to Darwin’) who had died the year before. One such tribute appeared in 'The Century', an illustrated monthly magazine. As part of this article he included a summary of Darwin's work relating to this book ...	{ "page_id": 33748539, "title": "The Different Forms of Flowers on Plants of the Same Species" }
the fertility of this common plant. The same thing was found to occur in the primrose, as well as in flax (Linum perenne), lungworts (Pulmonaria), and a host of other plants, including the American partridge-berry (Mitchella repens). These are called dimorphic heterostyled plants. Still more extraordinary is the case o...	{ "page_id": 33748539, "title": "The Different Forms of Flowers on Plants of the Same Species" }
CUL-DAR140.3.1—159 Transcribed by Robert Brown (Darwin Online, http://darwin-online.org.uk/). Wallace, Alfred R. 1883. 'The Debt of Science to Darwin' in 'The Century', in Vol XXV; new series volume III – pages 420 – 432 == External links == The Different Forms of Flowers on Plants of the Same Species at Project Gutenb...	{ "page_id": 33748539, "title": "The Different Forms of Flowers on Plants of the Same Species" }

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