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to fail. Which was promptly called play farming due to the idea of "farmers" experimenting with agriculture. In addition, the ability for humans to stay within one place for food and create permanent settlements made the process move along faster. During this transitional period, crops began to acclimate and evolve wit...	{ "page_id": 200646, "title": "Selective breeding" }
education of the concerned people – researchers, advisory personnel and fish farmers. The education of fish biologists paid less attention to quantitative genetics and breeding plans. Another was the failure of documentation of the genetic gains in successive generations. This in turn led to failure in quantifying econ...	{ "page_id": 200646, "title": "Selective breeding" }
is usually high it is not considered as a major trait for improvement. However, selective breeding practices may consider the size of the egg and correlate it with survival and early growth rate. === Finfish response to selection === ==== Salmonids ==== Gjedrem (1979) showed that selection of Atlantic salmon (Salmo sal...	{ "page_id": 200646, "title": "Selective breeding" }
Chile, Neira et al. (2006) conducted experiments on early spawning dates in coho salmon. After selectively breeding the fish for four generations, spawning dates were 13–15 days earlier. Cyprinids Selective breeding programs for the Common carp (Cyprinus carpio) include improvement in growth, shape and resistance to di...	{ "page_id": 200646, "title": "Selective breeding" }
flat oyster Ostrea edulis L. This protistan parasite is endemic to three oyster-regions in Europe. Selective breeding programs show that O. edulis susceptibility to the infection differs across oyster strains in Europe. A study carried out by Culloty et al. showed that 'Rossmore' oysters in Cork harbour, Ireland had be...	{ "page_id": 200646, "title": "Selective breeding" }
as parents for the next generation. They achieved satisfying results in two or three generations wherein survival rates approached levels before the outbreak of the disease. The resulting heavy losses (up to 90%) caused by Infectious hypodermal and haematopoietic necrosis virus (IHHNV) caused a number of shrimp farming...	{ "page_id": 200646, "title": "Selective breeding" }
It is not uncommon for fish to escape the nets or pens that they are kept in, especially in mass. If these fish are farmed in areas they are not native to they may be able to establish themselves and outcompete native populations of fish, and cause ecological harm as an invasive species. Furthermore, if they are in are...	{ "page_id": 200646, "title": "Selective breeding" }
breeding. Additionally, selective breeding can lead to a variety of issues including reduction of genetic diversity or physical problems. The process of selective breeding can create physical issues for plants or animals such as dogs selectively bred for extremely small sizes dislocating their kneecaps at a much more f...	{ "page_id": 200646, "title": "Selective breeding" }
In chemistry, the term chemically inert is used to describe a substance that is not chemically reactive. From a thermodynamic perspective, a substance is inert, or nonlabile, if it is thermodynamically unstable (negative standard Gibbs free energy of formation) yet decomposes at a slow, or negligible rate. Most of the ...	{ "page_id": 17633222, "title": "Chemically inert" }
does react with the alkali metal lithium to form compound lithium nitride (Li3N), even under ordinary conditions. Under high pressures and temperatures and with the right catalysts, nitrogen becomes more reactive; the Haber process uses such conditions to produce ammonia from atmospheric nitrogen. === Main uses === Ine...	{ "page_id": 17633222, "title": "Chemically inert" }
A compositional domain in genetics is a region of DNA with a distinct guanine (G) and cytosine (C) G-C and C-G content (collectively GC content). The homogeneity of compositional domains is compared to that of the chromosome on which they reside. As such, compositional domains can be homogeneous or nonhomogeneous domai...	{ "page_id": 35590090, "title": "Compositional domain" }
ones. == References == == External links == IsoPlotter — a free, open source program to calculate and visualize isochores in a given genome	{ "page_id": 35590090, "title": "Compositional domain" }
A microbial electrolysis cell (MEC) is a technology related to Microbial fuel cells (MFC). Whilst MFCs produce an electric current from the microbial decomposition of organic compounds, MECs partially reverse the process to generate hydrogen or methane from organic material by applying an electric current. The electric...	{ "page_id": 23400395, "title": "Microbial electrolysis cell" }
of microbes. Hydrogen production has reached up to 3.12 m3H2/m3d with an input voltage of 0.8 volts. The efficiency of hydrogen production depends on which organic substances are used. Lactic and acetic acid achieve 82% efficiency, while the values for unpretreated cellulose or glucose are close to 63%. The efficiency ...	{ "page_id": 23400395, "title": "Microbial electrolysis cell" }
cells Microbial electrolysis carbon capture == References == == External links == National Science Foundation The University of Queensland Scientific Blogging [1]	{ "page_id": 23400395, "title": "Microbial electrolysis cell" }
A truss is an assembly of members such as beams, connected by nodes, that creates a rigid structure. In engineering, a truss is a structure that "consists of two-force members only, where the members are organized so that the assemblage as a whole behaves as a single object". A two-force member is a structural componen...	{ "page_id": 397263, "title": "Truss" }
necessarily) straight members connected at joints, traditionally termed panel points. Trusses are typically (but not necessarily) composed of triangles because of the structural stability of that shape and design. A triangle is the simplest geometric figure that will not change shape when the lengths of the sides are f...	{ "page_id": 397263, "title": "Truss" }
depth of the truss will maximize the efficiency. === Space frame truss === A space frame truss is a three-dimensional framework of members pinned at their ends. A tetrahedron shape is the simplest space truss, consisting of six members that meet at four joints. Large planar structures may be composed from tetrahedrons ...	{ "page_id": 397263, "title": "Truss" }
the Pratt truss is probably due to the fact that the configuration of the members means that longer diagonal members are only in tension for gravity load effects. This allows these members to be used more efficiently, as slenderness effects related to buckling under compression loads (which are compounded by the length...	{ "page_id": 397263, "title": "Truss" }
to a king post truss in that the outer supports are angled towards the centre of the structure. The primary difference is the horizontal extension at the centre which relies on beam action to provide mechanical stability. This truss style is only suitable for relatively short spans. === Lenticular truss === Lenticular ...	{ "page_id": 397263, "title": "Truss" }
apply to the structure as a whole, as well as to each node or joint. In order for any node that may be subject to an external load or force to remain static in space, the following conditions must hold: the sums of all (horizontal and vertical) forces, as well as all moments acting about the node, equal zero. Analysis ...	{ "page_id": 397263, "title": "Truss" }
with more than this minimum number of truss members. Those structures may survive even when some of the members fail. Their member forces depend on the relative stiffness of the members, in addition to the equilibrium condition described. == Analysis == Because the forces in each of its two main girders are essentially...	{ "page_id": 397263, "title": "Truss" }
a symmetrical truss with symmetrical vertical loads, the reactive forces at A and B are vertical, equal, and half the total load. The internal forces in the members of the truss can be calculated in a variety of ways, including graphical methods: Cremona diagram Culmann diagram Ritter analytical method (method of secti...	{ "page_id": 397263, "title": "Truss" }
the design decisions beyond mere matters of economics. Modern materials such as prestressed concrete and fabrication methods such as automated welding have significantly influenced the design of modern bridges. Once the force on each member is known, the next step is to determine the cross section of the individual tru...	{ "page_id": 397263, "title": "Truss" }
the design of a truss would be detailing of the bolted joints, e.g., involving shear stress of the bolt connections used in the joints. Based on the needs of the project, truss internal connections (joints) can be designed as rigid, semi-rigid, or hinged. Rigid connections can allow transfer of bending moments, leading...	{ "page_id": 397263, "title": "Truss" }
Hundreds of replicas of the Statue of Liberty (Liberty Enlightening the World) have been created worldwide. The original Statue of Liberty, designed by sculptor Frédéric Auguste Bartholdi, is 151 feet tall and stands on a pedestal that is 154 feet tall, making the height of the entire sculpture 305 feet. The design for...	{ "page_id": 5378000, "title": "Replicas of the Statue of Liberty" }
statue is a short distance away from the Eiffel Tower and Alexandre-Gustave Eiffel designed its interior. This model weighs 14 tons. It was inaugurated on 4 July 1889. Its tablet bears two dates: "IV JUILLET 1776" (4 July 1776: the United States Declaration of Independence) like the New York statue, and "XIV JUILLET 17...	{ "page_id": 5378000, "title": "Replicas of the Statue of Liberty" }
Princess of Wales after she was killed in a car accident in the Pont de l'Alma tunnel. === Barentin === There is a 13.5 m (44 feet) polyester replica in the northwest of France, in the small town of Barentin near Rouen. It was made for the 1969 French film, Le Cerveau ("The Brain"), directed by Gérard Oury and featurin...	{ "page_id": 5378000, "title": "Replicas of the Statue of Liberty" }
the US 48th Tactical Fighter Wing, now based at Lakenheath, England, with its own statue at the flag plaza. The 48th TFW is the only USAF wing with a name: "The Statue of Liberty Wing". Another example is of a Liberty Enlightening the World replica in Châteauneuf-la-Forêt, near the city of Limoges in the area of Haute-...	{ "page_id": 5378000, "title": "Replicas of the Statue of Liberty" }
More, County Donegal, Ireland. === Kosovo === A replica stands atop the Hotel Victory in Pristina, Kosovo. Today the Hotel is closed and the Police from Kosovo used the building. === Netherlands === A 33 ft (10 m) replica has its temporary location in the Dutch city of Assen. The statue bears characteristic features th...	{ "page_id": 5378000, "title": "Replicas of the Statue of Liberty" }
architect Yuriy Zakharevych and decorated by sculptor Leandro Marconi in 1874–1891. === United Kingdom === A 17 ft (5.2 m), 9,200 kg (9.2 tons) replica stood atop the Liberty Shoe factory in Leicester, England, until 2002 when the building was demolished. The statue was put into storage while the building was replaced....	{ "page_id": 5378000, "title": "Replicas of the Statue of Liberty" }
Liberty Warehouse. In February 2002, the statue was removed by the building's owners to allow the building to be expanded. It was donated to the Brooklyn Museum of Art, which installed it in its sculpture garden in October 2005 with plans to restore it on site in spring of 2006. A replica that used to reside at the Mus...	{ "page_id": 5378000, "title": "Replicas of the Statue of Liberty" }
businessman J.P. Whitaker, who was then Scout Commissioner of the Kansas City Area Council. The copper statues were manufactured by Friedley-Voshardt Co. (Chicago, Illinois) and purchased through the Kansas City Boy Scout office by those wanting one. The statues are approximately 8+1⁄2 feet (2.6 m) tall without the bas...	{ "page_id": 5378000, "title": "Replicas of the Statue of Liberty" }
and lost-wax casting methods, and is the only one currently on public display. The statue itself is 9 feet tall and 15 feet including the pedestal on which it stands. There is a half-size replica at the New York-New York Hotel and Casino in Las Vegas, Nevada. In April 2011, the U.S. Postal Service announced that three ...	{ "page_id": 5378000, "title": "Replicas of the Statue of Liberty" }
later, after it was destroyed in a windstorm, it was rebuilt by Stilp and other local citizens, of wood, metal, glass and fiberglass, to a height of 25 feet (7.6 m). A Lego replica of the Statue of Liberty consisting of 2882 bricks and standing 0.9 m (3.0 ft) is a popular sculpture among Lego enthusiasts. The statue we...	{ "page_id": 5378000, "title": "Replicas of the Statue of Liberty" }
the entrance of the Main Avenue bridge, which was reported stolen on July 26, 2019. There is a replica on the shoreline of Lake Chaubunagungamaug in Webster, Massachusetts. A 1/6-scale replica (≈50 feet including pedestal) stands in a parking lot of a strip mall in Milwaukie, Oregon, off McLoughlin Blvd at 4255 SE Roet...	{ "page_id": 5378000, "title": "Replicas of the Statue of Liberty" }
Service in Leavittsburg, Ohio. It was donated to Newton Falls by the former owner of Liberty Tax Service when she closed the business. A 7-foot, 7-inch replica of the statue, built in 2013, stands in Old Church Park at the corner of Cherry and Morning Streets in Sunbury, Ohio. A replica of the statue stands in Guam, at...	{ "page_id": 5378000, "title": "Replicas of the Statue of Liberty" }
celebrate the 10th anniversary of the Republic of Brazil. Until 1940, the statue was Paranhos family property. In 1940 the statue was passed to Guanabara State. On 20 January 1964, Carlos Lacerda, governor of Guanabara State, placed the statue in Miami Square, Bangu. 22.856681°S 43.492577°W / -22.856681; -43.492577 A ...	{ "page_id": 5378000, "title": "Replicas of the Statue of Liberty" }
49.2521676°W / -25.4639912; -49.2521676 Also, there is a small replica of the statue in Belém, in front of a Belém Importados store, near the city's port. === Ecuador === In Guayaquil, a little replica gives the name of "New York" to a neighborhood in the Valle Alto area. === Peru === In Lima the New York Casino in th...	{ "page_id": 5378000, "title": "Replicas of the Statue of Liberty" }
of that statue.) ==== Shenzhen ==== A replica can be found in Window of the World Park. === Israel === A 15 foot high replica of the Statue of Liberty is at the western entrance of the village of Arraba in Israel, near a local restaurant. At a highway intersection in Jerusalem called "New York Square," there is an abst...	{ "page_id": 5378000, "title": "Replicas of the Statue of Liberty" }
replica in the Philippines. The said monument was supposed to be sponsored by The Chicago Daily Times whose goal was "to commemorate one of the great epics in the struggle for human freedom–the liberation of the Philippines." In 1950, the Boy Scouts of America marked its 40th anniversary. Jack P. Whitaker, the Scout Co...	{ "page_id": 5378000, "title": "Replicas of the Statue of Liberty" }
and Manila City Hall.” In the end, the Boy Scouts of the Philippines (BSP) erected the statue just outside Intramuros. As the icon of the United States, the replica of Lady Liberty would survive several attacks by student protesters in the 1960s. It remained standing until the early 1970s, when the BSP decided to trans...	{ "page_id": 5378000, "title": "Replicas of the Statue of Liberty" }
Bonifacio and the Liberty statues. Since the creation of the Liberty statues in Intramuros and Juan Luna Street, other Philippine provinces soon followed suit. Statue of Liberty replicas in can be found in Pangasinan and as far as Camp John Hay amphitheater in Baguio. === Thailand === The Mini Siam and Mini Europe mode...	{ "page_id": 5378000, "title": "Replicas of the Statue of Liberty" }
Kampō (or Kanpō, 漢方) medicine is the Japanese study and adaptation of traditional Chinese medicine. In 1967, the Japanese Ministry of Health, Labour and Welfare approved four kampo medicines for reimbursement under the National Health Insurance (NHI) program. In 1976, 82 kampo medicines were approved by the Ministry of...	{ "page_id": 9179093, "title": "List of kampo herbs" }
DIMPL (Discovery of Intergenic Motifs PipeLine) is a bioinformatic pipeline that enables the extraction and selection of bacterial GC-rich intergenic regions (IGRs) that are enriched for structured non-coding RNAs (ncRNAs). The method of enriching bacterial IGRs for ncRNA motif discovery was first reported for a study ...	{ "page_id": 69144535, "title": "DIMPL" }
rnn is an open-source machine learning framework that implements recurrent neural network architectures, such as LSTM and GRU, natively in the R programming language, that has been downloaded over 100,000 times (from the RStudio servers alone). The rnn package is distributed through the Comprehensive R Archive Network ...	{ "page_id": 57741272, "title": "Rnn (software)" }
Rodentology is a branch of mammalogy for the study of rodents by a rodentologist. The scientific group of rodents would include, but is not limited to, mice, rats, squirrels, etc. From the perspective of zoology, it investigates the behaviour, biology and classification of various rodent species. The study of rodents i...	{ "page_id": 77729754, "title": "Rodentology" }
The flatness problem (also known as the oldness problem) is a cosmological fine-tuning problem within the Big Bang model of the universe. Such problems arise from the observation that some of the initial conditions of the universe appear to be fine-tuned to very 'special' values, and that small deviations from these va...	{ "page_id": 1118171, "title": "Flatness problem" }
a small area. On large scales however, space is bent by the gravitational effect of matter. Since relativity indicates that matter and energy are equivalent, this effect is also produced by the presence of energy (such as light and other electromagnetic radiation) in addition to matter. The amount of bending (or curvat...	{ "page_id": 1118171, "title": "Flatness problem" }
\rho _{c}} can be determined. Its value is currently around 10−26 kg m−3. The ratio of the actual density to this critical value is called Ω, and its difference from 1 determines the geometry of the universe: Ω > 1 corresponds to a greater than critical density, ρ > ρ c {\displaystyle \rho >\rho _{c}} , and hence a clo...	{ "page_id": 1118171, "title": "Flatness problem" }
term has decreased by a factor of around 10 60 , {\displaystyle 10^{60},} and so ( Ω − 1 − 1 ) {\displaystyle (\Omega ^{-1}-1)} must have increased by a similar amount to retain the constant value of their product. == Current value of Ω == === Measurement === The value of Ω at the present time is denoted Ω0. This value...	{ "page_id": 1118171, "title": "Flatness problem" }
Earth. These supernovae, the explosions of degenerate white dwarf stars, are a type of standard candle; this means that the processes governing their intrinsic brightness are well understood so that a measure of apparent brightness when seen from Earth can be used to derive accurate distance measures for them (the appa...	{ "page_id": 1118171, "title": "Flatness problem" }
Bang in which all matter and energy falls back into an extremely dense state) in a few years or less; in the case of an underdensity ( ρ < ρ c {\displaystyle \rho <\rho _{c}} ) it would expand so quickly and become so sparse it would soon seem essentially empty, and gravity would not be strong enough by comparison to c...	{ "page_id": 1118171, "title": "Flatness problem" }
only one is suitable for the evolution of intelligent life, the anthropic principle suggests that finding ourselves in that universe is no surprise: if the other universe had existed instead, there would be no observers to notice the fact. The principle can be applied to solve the flatness problem in two somewhat diffe...	{ "page_id": 1118171, "title": "Flatness problem" }
those patches with Ω very close to 1, and that therefore our living in such a patch is unsurprising. This latter argument makes use of a version of the anthropic principle which is 'weaker' in the sense that it requires no speculation on multiple universes, or on the probabilities of various different universes existin...	{ "page_id": 1118171, "title": "Flatness problem" }
inflation model, he was not trying to solve either the flatness or horizon problems. Indeed, at that time, he knew nothing of the horizon problem and had never quantitatively calculated the flatness problem". He was a particle physicist trying to solve the magnetic monopole problem." The proposed cause of inflation is ...	{ "page_id": 1118171, "title": "Flatness problem" }
some physicists deny that inflationary theory resolves the flatness problem, arguing that it merely moves the fine-tuning from the probability distribution to the potential of a field, or even deny that it is a scientific theory. === Post inflation === Although inflationary theory is regarded as having had much success...	{ "page_id": 1118171, "title": "Flatness problem" }
but only for a relatively short time, so a typical observer would not expect to measure Ω appreciably different from 1; in the case of a universe which expands forever with a positive cosmological constant, fine-tuning is needed not to achieve a (nearly) flat universe, but also to avoid it. === Einstein–Cartan theory =...	{ "page_id": 1118171, "title": "Flatness problem" }
In organophosphorus chemistry, the Kabachnik–Fields reaction is a three-component organic reaction forming α-aminomethylphosphonates from an amine, a carbonyl compound, and a dialkyl phosphonate, (RO)2P(O)H (that are also called dialkylphosphites). Aminophosphonates are synthetic targets of some importance as phosphoru...	{ "page_id": 22024157, "title": "Kabachnik–Fields reaction" }
The Rolf Wideroe Prize is awarded every third year by the Accelerator Group of the European Physical Society (EPS), in memory of Rolf Widerøe, to individuals in recognition of outstanding work in the field of accelerator physics. The prize was awarded for the first time in 1996, but was only named the Rolf Wideroe Priz...	{ "page_id": 64032738, "title": "Rolf Wideroe Prize" }
In general relativity, Regge–Wheeler–Zerilli equations are a pair of equations that describe gravitational perturbations of a Schwarzschild black hole, named after Tullio Regge, John Archibald Wheeler and Frank J. Zerilli. The perturbations of a Schwarzchild metric is classified into two types, namely, axial and polar ...	{ "page_id": 71241698, "title": "Regge–Wheeler–Zerilli equations" }
= 2 ( r 2 − 2 M r ) r 5 ( n r + 3 M ) 2 [ n 2 ( n + 1 ) r 3 + 3 M n 2 r 2 + 9 M 2 n r + 9 M 3 ] {\displaystyle V^{+}={\frac {2(r^{2}-2Mr)}{r^{5}(nr+3M)^{2}}}[n^{2}(n+1)r^{3}+3Mn^{2}r^{2}+9M^{2}nr+9M^{3}]} where 2 n = ( l − 1 ) ( l + 2 ) {\displaystyle 2n=(l-1)(l+2)} and l = 2 , 3 , 4 , … {\displaystyle l=2,3,4,\dots } ...	{ "page_id": 71241698, "title": "Regge–Wheeler–Zerilli equations" }
i σ r ∗ . {\displaystyle e^{\pm i\sigma r_{*}}.} == Relations between the two problems == In 1975, Subrahmanyan Chandrasekhar and Steven Detweiler discovered a one-to-one mapping between the two equations, leading to a consequence that the spectrum corresponding to both potentials are identical. The two potentials can ...	{ "page_id": 71241698, "title": "Regge–Wheeler–Zerilli equations" }
− i σ r ∗ as r ∗ → + ∞ {\displaystyle Z^{\pm }=e^{+i\sigma r_{}}+R^{\pm }e^{-i\sigma r_{}}\quad {\text{as}}\quad r_{}\rightarrow +\infty } Z ± = T ± e i σ r ∗ as r ∗ → − ∞ {\displaystyle Z^{\pm }=T^{\pm }e^{i\sigma r_{}}\quad {\text{as}}\quad r_{*}\rightarrow -\infty } where R = R ( σ ) {\displaystyle R=R(\sigma )}...	{ "page_id": 71241698, "title": "Regge–Wheeler–Zerilli equations" }
multipole. == Quasi-normal modes == Quasi-normal modes correspond to pure tones of the black hole. These tones are excited when arbitrary, but small, perturbations imping on a black hole, such as an object falling into it, accretion of matter surrounding it, the last stage of slightly aspherical collapse, the last stag...	{ "page_id": 71241698, "title": "Regge–Wheeler–Zerilli equations" }
V − = 0 , ϕ ( − ∞ ) = + σ , ϕ ( + ∞ ) = − σ . {\displaystyle i{\frac {d\phi }{dr_{*}}}+\sigma ^{2}-\phi ^{2}-V^{-}=0,\quad \phi (-\infty )=+\sigma ,\quad \phi (+\infty )=-\sigma .} The solution is found to exist only for a discrete set of values of σ . {\displaystyle \sigma .} This equation also implies the identity − ...	{ "page_id": 71241698, "title": "Regge–Wheeler–Zerilli equations" }
An enyne is an organic compound containing a C=C double bond (alkene) and a C≡C triple bond (alkyne). It is called a conjugated enyne when the double and triple bonds are conjugated. The term is a contraction of the terms alkene and alkyne. The simplest enyne is vinylacetylene. The organic enynes are isanolic acid and ...	{ "page_id": 3411940, "title": "Enyne" }
The molecular formula C15H11NO3 (molar mass: 253.25 g/mol, exact mass: 253.073894 u) may refer to: Cridanimod Furegrelate	{ "page_id": 79171557, "title": "C15H11NO3" }
A gamma ray, also known as gamma radiation (symbol γ), is a penetrating form of electromagnetic radiation arising from high energy interactions like the radioactive decay of atomic nuclei or astronomical events like solar flares. It consists of the shortest wavelength electromagnetic waves, typically shorter than those...	{ "page_id": 18616290, "title": "Gamma ray" }
so the terminology for these electromagnetic waves varies between scientific disciplines. In some fields of physics, they are distinguished by their origin: gamma rays are created by nuclear decay while X-rays originate outside the nucleus. In astrophysics, gamma rays are conventionally defined as having photon energie...	{ "page_id": 18616290, "title": "Gamma ray" }
analogy with the beta and alpha rays that Rutherford had differentiated in 1899. The "rays" emitted by radioactive elements were named in order of their power to penetrate various materials, using the first three letters of the Greek alphabet: alpha rays as the least penetrating, followed by beta rays, followed by gamm...	{ "page_id": 18616290, "title": "Gamma ray" }
of such astronomical gamma rays are screened by Earth's atmosphere. Notable artificial sources of gamma rays include fission, such as occurs in nuclear reactors, as well as high energy physics experiments, such as neutral pion decay and nuclear fusion. A sample of gamma ray-emitting material that is used for irradiatin...	{ "page_id": 18616290, "title": "Gamma ray" }
In certain cases, the excited nuclear state that follows the emission of a beta particle or other type of excitation, may be more stable than average, and is termed a metastable excited state, if its decay takes (at least) 100 to 1000 times longer than the average 10−12 seconds. Such relatively long-lived excited nucle...	{ "page_id": 18616290, "title": "Gamma ray" }
decays to excited 60Ni by beta decay emission of an electron of 0.31 MeV. Then the excited 60Ni decays to the ground state (see nuclear shell model) by emitting gamma rays in succession of 1.17 MeV followed by 1.33 MeV. This path is followed 99.88% of the time: Another example is the alpha decay of 241Am to form 237Np;...	{ "page_id": 18616290, "title": "Gamma ray" }
sources === A few gamma rays in astronomy are known to arise from gamma decay (see discussion of SN1987A), but most do not. Photons from astrophysical sources that carry energy in the gamma radiation range are often explicitly called gamma-radiation. In addition to nuclear emissions, they are often produced by sub-atom...	{ "page_id": 18616290, "title": "Gamma ray" }
(see illustration at right) is dominated by the more common and longer-term production of gamma rays that emanate from pulsars within the Milky Way. Sources from the rest of the sky are mostly quasars. Pulsars are thought to be neutron stars with magnetic fields that produce focused beams of radiation, and are far less...	{ "page_id": 18616290, "title": "Gamma ray" }
they produce X-rays and gamma rays. These sources are known to fluctuate with durations of a few weeks, suggesting their relatively small size (less than a few light-weeks across). Such sources of gamma and X-rays are the most commonly visible high intensity sources outside the Milky Way galaxy. They shine not in burst...	{ "page_id": 18616290, "title": "Gamma ray" }
few tens of seconds by the magnetic field of the exploding hypernova. The fusion explosion of the hypernova drives the energetics of the process. If the narrowly directed beam happens to be pointed toward the Earth, it shines at gamma ray frequencies with such intensity, that it can be detected even at distances of up ...	{ "page_id": 18616290, "title": "Gamma ray" }
4.1 cm of granite rock, 6 cm (2.5 inches) of concrete, or 9 cm (3.5 inches) of packed soil. However, the mass of this much concrete or soil is only 20–30% greater than that of lead with the same absorption capability. Depleted uranium is sometimes used for shielding in portable gamma ray sources, due to the smaller hal...	{ "page_id": 18616290, "title": "Gamma ray" }
the resulting photoelectron is equal to the energy of the incident gamma photon minus the energy that originally bound the electron to the atom (binding energy). The photoelectric effect is the dominant energy transfer mechanism for X-ray and gamma ray photons with energies below 50 keV (thousand electronvolts), but it...	{ "page_id": 18616290, "title": "Gamma ray" }
least 0.51 MeV energy each (or higher according to the kinetic energy of the annihilated particles). The secondary electrons (and/or positrons) produced in any of these three processes frequently have enough energy to produce much ionization themselves. Additionally, gamma rays, particularly high energy ones, can inter...	{ "page_id": 18616290, "title": "Gamma ray" }
them, this energy is also sufficient to excite the same energy state in a second immobilized nucleus of the same type. == Applications == Gamma rays provide information about some of the most energetic phenomena in the universe; however, they are largely absorbed by the Earth's atmosphere. Instruments aboard high-altit...	{ "page_id": 18616290, "title": "Gamma ray" }
damage to surrounding tissues. Gamma rays are also used for diagnostic purposes in nuclear medicine in imaging techniques. A number of different gamma-emitting radioisotopes are used. For example, in a PET scan a radiolabeled sugar called fluorodeoxyglucose emits positrons that are annihilated by electrons, producing p...	{ "page_id": 18616290, "title": "Gamma ray" }
(Gy).: 61 === Effects and body response === When gamma radiation breaks DNA molecules, a cell may be able to repair the damaged genetic material, within limits. However, a study of Rothkamm and Lobrich concerning X-ray radiation has shown that this repair process works well after high-dose exposure but is much slower i...	{ "page_id": 18616290, "title": "Gamma ray" }
the annual background). An acute full-body equivalent single exposure dose of 1 Sv (1000 mSv), or 1 Gy, will cause mild symptoms of acute radiation sickness, such as nausea and vomiting; and a dose of 2.0–3.5 Sv (2.0–3.5 Gy) causes more severe symptoms (i.e. nausea, diarrhea, hair loss, hemorrhaging, and inability to f...	{ "page_id": 18616290, "title": "Gamma ray" }
gamma and other ionizing radiation on living tissue is more closely related to the amount of energy deposited in tissue rather than the ionisation of air, and replacement radiometric units and quantities for radiation protection have been defined and developed from 1953 onwards. These are: The gray (Gy), is the SI unit...	{ "page_id": 18616290, "title": "Gamma ray" }
now completely overlap. Thus, gamma rays are now usually distinguished by their origin: X-rays are emitted by definition by electrons outside the nucleus, while gamma rays are emitted by the nucleus. Exceptions to this convention occur in astronomy, where gamma decay is seen in the afterglow of certain supernovas, but ...	{ "page_id": 18616290, "title": "Gamma ray" }
is always referred to as "gamma rays", and never as X-rays. However, in physics and astronomy, the converse convention (that all gamma rays are considered to be of nuclear origin) is frequently violated. In astronomy, higher energy gamma and X-rays are defined by energy, since the processes that produce them may be unc...	{ "page_id": 18616290, "title": "Gamma ray" }
Data Search – Contains information on gamma-ray energies from isotopes. Mapping soils with airborne detectors Archived 2010-11-11 at the Wayback Machine The LIVEChart of Nuclides – IAEA with filter on gamma-ray energy Health Physics Society Public Education Website	{ "page_id": 18616290, "title": "Gamma ray" }
A transitional fossil is any fossilized remains of a life form that exhibits traits common to both an ancestral group and its derived descendant group. This is especially important where the descendant group is sharply differentiated by gross anatomy and mode of living from the ancestral group. These fossils serve as a...	{ "page_id": 331755, "title": "Transitional fossil" }
most commonly used to refer to any new transitional fossil finds. Scientists, however, do not use the term, as it refers to a pre-evolutionary view of nature. == Evolutionary and phylogenetic taxonomy == === Transitions in phylogenetic nomenclature === In evolutionary taxonomy, the prevailing form of taxonomy during mu...	{ "page_id": 331755, "title": "Transitional fossil" }
that one of the goals of evolutionary taxonomy is to identify taxa that were ancestors of other taxa. However, because evolution is a branching process that produces a complex bush pattern of related species rather than a linear process producing a ladder-like progression, and because of the incompleteness of the fossi...	{ "page_id": 331755, "title": "Transitional fossil" }
a raven, Archaeopteryx could grow to about 0.5 metres (1.6 ft) in length. Despite its small size, broad wings, and inferred ability to fly or glide, Archaeopteryx has more in common with other small Mesozoic dinosaurs than it does with modern birds. In particular, it shares the following features with the deinonychosau...	{ "page_id": 331755, "title": "Transitional fossil" }
The femur angles in toward the knee from the hip. This trait allows the foot to fall closer to the midline of the body, and strongly indicates habitual bipedal locomotion. Present-day humans, orangutans and spider monkeys possess this same feature. The feet feature adducted big toes, making it difficult if not impossib...	{ "page_id": 331755, "title": "Transitional fossil" }
is clear that ambulocetids tolerated a wide range of salt concentrations. Their diet probably included land animals that approached water for drinking, or freshwater aquatic organisms that lived in the river. Hence, ambulocetids represent the transition phase of cetacean ancestors between freshwater and marine habitat....	{ "page_id": 331755, "title": "Transitional fossil" }
Tiktaalik is an example), implying that animals like Tiktaalik, possessing features that evolved around 400 million years ago, were "late-surviving relics rather than direct transitional forms, and they highlight just how little we know of the earliest history of land vertebrates." === Amphistium === Pleuronectiformes ...	{ "page_id": 331755, "title": "Transitional fossil" }
an unopened distal extension protruding above the multilobed integument. It is suspected that the extension was involved in anemophilous pollination. Runcaria sheds new light on the sequence of character acquisition leading to the seed, having all the qualities of seed plants except for a solid seed coat and a system t...	{ "page_id": 331755, "title": "Transitional fossil" }
back as the 18th century. Darwin's On the Origin of Species, published in 1859, gave it a firm scientific basis. A weakness of Darwin's work, however, was the lack of palaeontological evidence, as pointed out by Darwin himself. While it is easy to imagine natural selection producing the variation seen within genera and...	{ "page_id": 331755, "title": "Transitional fossil" }
mosses, and it has been shown that Rhynia had an alternation of generations, with a corresponding gametophyte in the form of crowded tufts of diminutive stems only a few millimetres in height. Rhynia thus falls midway between mosses and early vascular plants like ferns and clubmosses. From a carpet of moss-like gametop...	{ "page_id": 331755, "title": "Transitional fossil" }
findings in his Antiquity of Man to put the origin of human beings much further back. Lyell wrote that it remained a profound mystery how the huge gulf between man and beast could be bridged. Lyell's vivid writing fired the public imagination, inspiring Jules Verne's Journey to the Center of the Earth (1864) and Louis ...	{ "page_id": 331755, "title": "Transitional fossil" }

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