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}}\cdot \mathbf {B} =0} . the strength is constant at any surface along a flux tube. Under the condition that the cross-sectional area, A {\displaystyle A} , of the flux tube is small enough that the magnetic field is approximately constant, F {\displaystyle F} can be approximated as F ≈ B A {\displaystyle F\approx BA}...	{ "page_id": 4595931, "title": "Flux tube" }
+ ∮ C B ⋅ v × d ℓ . {\displaystyle {\frac {d\Phi _{B}}{dt}}=\int _{S}{\partial \mathbf {B} \over \partial t}\cdot d\mathbf {S} +\oint _{C}\mathbf {B} \cdot \mathbf {v} \times d{\boldsymbol {\ell }}.} Using the induction equation gives d Φ B d t = ∫ S ∇ × ( v × B ) ⋅ d S + ∮ C B ⋅ v × d ℓ {\displaystyle {\frac {d\Phi _{...	{ "page_id": 4595931, "title": "Flux tube" }
the flux tube by λ ∗ {\displaystyle \lambda ^{}} gives a new length of L = λ ∗ L 0 {\displaystyle L=\lambda ^{}L_{0}} while the density of the tube remains the same, ρ 0 {\displaystyle \rho _{0}} , which then results in the magnetic field strength increasing by λ ∗ B 0 {\displaystyle \lambda ^{*}B_{0}} . Reducing the...	{ "page_id": 4595931, "title": "Flux tube" }
Solar === Examples of solar flux tubes include sunspots and intense magnetic tubes in the photosphere and the field around the solar prominence and coronal loops in the corona. Sunspots occur when small flux tubes combine into a large flux tube that breaks the surface of the photosphere. The large flux tube of the suns...	{ "page_id": 4595931, "title": "Flux tube" }
surroundings causing the pressure and density of the plasma to increase. These coronal loops get their characteristic high luminosity and ranges of shapes from the behavior of the magnetic flux tube. These flux tubes confine plasma and are characterized as isolated. The confined magnetic field strength varies from 0.1 ...	{ "page_id": 4595931, "title": "Flux tube" }
(MHD) Marklund convection == References ==	{ "page_id": 4595931, "title": "Flux tube" }
The dark forest hypothesis is the conjecture that many alien civilizations exist throughout the universe, but they are both silent and hostile, maintaining their undetectability for fear of being destroyed by another hostile and undetected civilization. It is one of many possible explanations of the Fermi paradox, whic...	{ "page_id": 72032480, "title": "Dark forest hypothesis" }
one is encountered, it is best to shoot first and ask questions later, in order to avoid the potential extinction of one’s own species. The novel provides a detailed investigation of Liu's concerns about alien contact. == Relationship to other proposed Fermi paradox solutions == The Berserker hypothesis, also known as ...	{ "page_id": 72032480, "title": "Dark forest hypothesis" }
Forge of God. In The Forge of God, humanity is likened to a baby crying in a hostile forest: "There once was an infant lost in the woods, crying its heart out, wondering why no one answered, drawing down the wolves." One of the characters explains, "We've been sitting in our tree chirping like foolish birds for over a ...	{ "page_id": 72032480, "title": "Dark forest hypothesis" }
through an alien character called Singer, who thinks that intelligent life that does not fear the dark forest would "expand and attack without fear". In other words, dark-forest-fearing civilizations are benign, civilizations that would reveal themselves are evil, and hunters are enforcers and protectors. == References...	{ "page_id": 72032480, "title": "Dark forest hypothesis" }
In chemical engineering, a multiple-effect evaporator is an apparatus for efficiently using the heat from steam to evaporate water. Water is boiled in a sequence of vessels, each held at a lower pressure than the last. Because the boiling temperature of water decreases as pressure decreases, the vapor boiled off in one...	{ "page_id": 1712357, "title": "Multiple-effect evaporator" }
Forward feed === In forward feed the condensate and the feed-concentrate move in the same direction. In this case the vacuum pressure can be sufficient to pull the feed through the system. === Backward feed === Here the concentrate flows in the opposite direction to the condensate. Pumps are required between stages, ho...	{ "page_id": 1712357, "title": "Multiple-effect evaporator" }
In polymer science, the Lifson–Roig model is a helix-coil transition model applied to the alpha helix-random coil transition of polypeptides; it is a refinement of the Zimm–Bragg model that recognizes that a polypeptide alpha helix is only stabilized by a hydrogen bond only once three consecutive residues have adopted ...	{ "page_id": 8921317, "title": "Lifson–Roig model" }
this modification can be represented as a matrix M, reflecting the statistical weights of the helix state h and coil state c. The Lifson–Roig model may be solved by the transfer-matrix method using the transfer matrix M shown at the right, where w is the statistical weight for helix propagation, v for initiation, n for...	{ "page_id": 8921317, "title": "Lifson–Roig model" }
An upstream open reading frame (uORF) is an open reading frame (ORF) within the 5' untranslated region (5'UTR) of an mRNA. uORFs can regulate eukaryotic gene expression. Translation of the uORF typically inhibits downstream expression of the primary ORF. However, in some genes such as yeast GCN4, translation of specifi...	{ "page_id": 23732455, "title": "Upstream open reading frame" }
Natural DNA damage is an alteration in the chemical structure of DNA, such as a break in a strand of DNA, a nucleobase missing from the backbone of DNA, or a chemically changed base such as 8-OHdG. DNA damage can occur naturally or via environmental factors, but is distinctly different from mutation, although both are ...	{ "page_id": 37626088, "title": "DNA damage (naturally occurring)" }
the cell is more vulnerable to DNA damage than any other part of the cell cycle. G2 checkpoint checks for damaged DNA and DNA replication completeness. == Types == Damage to DNA that occurs naturally can result from metabolic or hydrolytic processes. Metabolism releases compounds that damage DNA including reactive oxyg...	{ "page_id": 37626088, "title": "DNA damage (naturally occurring)" }
cell per day: 3,120 Cytosine deamination Mammalian cells, per cell per day: 192 Another important endogenous DNA damage is M1dG, short for (3-(2'-deoxy-beta-D-erythro-pentofuranosyl)-pyrimido[1,2-a]-purin-10(3H)-one). The excretion in urine (likely reflecting rate of occurrence) of M1dG may be as much as 1,000-fold low...	{ "page_id": 37626088, "title": "DNA damage (naturally occurring)" }
loss by replisome binding, replication stalling by transcription factors. The DDP human homologs are over-represented in known cancer drivers, and their RNAs in tumors predict heavy mutagenesis and a poor prognosis. == Repair of damaged DNA == In the presence of DNA damage, the cell can either repair the damage or indu...	{ "page_id": 37626088, "title": "DNA damage (naturally occurring)" }
in particular, cause 10,000-fold and 100,000-fold increases in intracellular ROS production, respectively. Inflammation-induced ROS that cause DNA damage can trigger apoptosis, but may also cause cancer if repair and apoptotic processes are insufficiently protective. Bile acids, stored in the gall bladder, are released...	{ "page_id": 37626088, "title": "DNA damage (naturally occurring)" }
light. Such oxidized bases can be repaired by base excision repair. When the 405 nm light is focused along a narrow line within the nucleus of a cell, about 2.5 seconds after irradiation, the chromatin remodeling enzyme Alc1 achieves half-maximum recruitment onto the irradiated micro-line. The line of chromatin that wa...	{ "page_id": 37626088, "title": "DNA damage (naturally occurring)" }
excision repair proteins, including ERCC1. === Homologous recombinational repair === Double-strand breaks (DSBs) at specific sites can be induced by transfecting cells with a plasmid encoding I-SceI endonuclease (a homing endonuclease). Multiple DSBs can be induced by irradiating sensitized cells (labeled with 5'-bromo...	{ "page_id": 37626088, "title": "DNA damage (naturally occurring)" }
can be detected in association with γH2AX. RNF8 mediates extensive chromatin decondensation, through its subsequent interaction with CHD4, a component of the nucleosome remodeling and deacetylase complex NuRD. === Pause for DNA repair === After rapid chromatin remodeling, cell cycle checkpoints may be activated to allo...	{ "page_id": 37626088, "title": "DNA damage (naturally occurring)" }
associated gene. When 8-oxo-dG is formed in a guanine rich, potential G-quadruplex-forming sequence (PQS) in the coding strand of a promoter, active OGG1 excises the 8-oxo-dG and generates an apurinic/apyrimidinic site (AP site). The AP site enables melting of the duplex to unmask the PQS, adopting a G-quadruplex fold ...	{ "page_id": 37626088, "title": "DNA damage (naturally occurring)" }
oxidizes the 5mC adjacent to the 8-OHdG. This initiates de-methylation of 5mC. TET1 is a key enzyme involved in de-methylating 5mCpG. However, TET1 is only able to act on 5mCpG if the guanine was first oxidized to form 8-hydroxy-2'-deoxyguanosine (8-OHdG or its tautomer 8-oxo-dG), resulting in a 5mCp-8-OHdG dinucleotid...	{ "page_id": 37626088, "title": "DNA damage (naturally occurring)" }
end joining (NHEJ) pathway factors, which perform a similar religation function to that of TOPIIβ, and the homologous recombination (HR) pathway, which uses the non-broken sister strand as a template to repair the damaged strand of DNA. Stimulation of neuronal activity, as previously mentioned in IEG expression, is ano...	{ "page_id": 37626088, "title": "DNA damage (naturally occurring)" }
DSBs and DNA repair molecules for neuronal-activity genes has been linked to the development of various human neurodegenerative diseases including Alzheimer's disease (AD), Parkinson's disease (PD), and amyotrophic lateral sclerosis (ALS). In patients with Alzheimer's disease, DSBs accumulate in neurons at early stages...	{ "page_id": 37626088, "title": "DNA damage (naturally occurring)" }
ATM, it is only difficult and extensive damage that requires ATR and ATM. ATM and ATR are required for NHEJ, HR, ICL repair, and NER, as well as replication fork stability during unperturbed DNA replication and in response to replication blocks. ATR is recruited for different forms of damage such as nucleotide damage, ...	{ "page_id": 37626088, "title": "DNA damage (naturally occurring)" }
is regulated by Mdm2 and constantly degraded. When there is DNA damage, Mdm2 is phosphorylated, most likely caused by ATM. The phosphorylation of Mdm2 leads to a reduction in the activity of Mdm2, thus preventing the degradation of p53. Normal, undamaged cell, usually has low levels of p53 while cells under stress and ...	{ "page_id": 37626088, "title": "DNA damage (naturally occurring)" }
other central genes in the SOS response pathway are found in almost all the bacterial genomes sequenced to date, covering a large number of phyla, suggesting both an ancient origin and a widespread occurrence of recombinational repair of DNA damage. Eukaryotic recombinases that are homologues of RecA are also widesprea...	{ "page_id": 37626088, "title": "DNA damage (naturally occurring)" }
al. summarized the evidence showing that single-strand breaks accumulate with age in the brain (though accumulation differed in different regions of the brain) and that single-strand breaks are the most frequent steady-state DNA damages in the brain. As discussed above, these accumulated single-strand breaks would be e...	{ "page_id": 37626088, "title": "DNA damage (naturally occurring)" }
cell viability and higher rates of damaged chromosomes compared with cells that are able to undergo a full G2 arrest, suggesting that the purpose of the delay is to give the cell time to repair damaged chromosomes before continuing with the cell cycle. This ensures the proper functioning of mitosis. Various species of ...	{ "page_id": 37626088, "title": "DNA damage (naturally occurring)" }
levels of x-irradiation, and rarely end up progressing through the later stages of the cell cycle. This is because the cells cannot repair DNA damage and thus do not enter mitosis. Various other rad mutants exhibit similar responses when exposed to x-irradiation. However, the rad9 strain exhibits an entirely different ...	{ "page_id": 37626088, "title": "DNA damage (naturally occurring)" }
evidence that the mutant RAD cells continued to divide and are deficient in G2 arrest. However, there is evidence that although the RAD9 gene is necessary to induce G2 arrest in response to DNA damage, giving the cell time to repair the damage, it does not actually play a direct role in repairing DNA. When rad9 cells a...	{ "page_id": 37626088, "title": "DNA damage (naturally occurring)" }
detecting DNA damage. When DNA is damaged, it is hypothesized that RAD9 forms a complex with RAD1 and HUS1, and this complex is recruited to sites of DNA damage. It is in this way that RAD9 is able to exert its effects. Although the function of RAD9 has primarily been studied in the budding yeast Saccharomyces cerevisi...	{ "page_id": 37626088, "title": "DNA damage (naturally occurring)" }
In crystallography, a crystallographic point group is a three-dimensional point group whose symmetry operations are compatible with a three-dimensional crystallographic lattice. According to the crystallographic restriction it may only contain one-, two-, three-, four- and sixfold rotations or rotoinversions. This redu...	{ "page_id": 663786, "title": "Crystallographic point group" }
is Cn with the addition of n mirror planes parallel to the axis of rotation. S2n (for Spiegel, German for mirror) denotes a group with only a 2n-fold rotation-reflection axis. Dn (for dihedral, or two-sided) indicates that the group has an n-fold rotation axis plus n twofold axes perpendicular to that axis. Dnh has, in...	{ "page_id": 663786, "title": "Crystallographic point group" }
table: This table makes use of cyclic groups (C1, C2, C3, C4, C6), dihedral groups (D2, D3, D4, D6), one of the alternating groups (A4), and one of the symmetric groups (S4). Here the symbol " × " indicates a direct product. == Deriving the crystallographic point group (crystal class) from the space group == Leave out ...	{ "page_id": 663786, "title": "Crystallographic point group" }
Nicholas Carlini is an American researcher affiliated with Anthropic and previously with Google DeepMind who has published research in the fields of computer security and machine learning. He is known for his work on adversarial machine learning, particularly his work on the Carlini & Wagner attack in 2016. This attack...	{ "page_id": 77078765, "title": "Nicholas Carlini" }
on the features of a parent model to increase the robustness and generalizability of student models. The attack gained popularity when it was shown that the methodology was also effective against most other defenses, rendering them ineffective. In 2018, Carlini demonstrated an attack against Mozilla Foundation's DeepSp...	{ "page_id": 77078765, "title": "Nicholas Carlini" }
ChatGPT would also sometimes output exact copies of webpages it was trained on, including personally identifiable information. Some of these studies have since been referenced by the courts in debating the copyright status of AI models. == Other work == Carlini received the Best of Show award at the 2020 IOCCC for impl...	{ "page_id": 77078765, "title": "Nicholas Carlini" }
Myron Mathisson (4 December 1897 – 13 September 1940) was a theoretical physicist of Polish and Jewish descent. He is known for his work in general relativity, for developing a new method to analyze the properties of fundamental solutions of linear hyperbolic partial differential equations, and proved, in a special cas...	{ "page_id": 40902897, "title": "Myron Mathisson" }
work === Due to financial difficulties, Mathisson had to work as a Hebrew translator, as a draftsman producing technical drawings, and engineering calculations of the statics of reinforced concrete structures. Mathisson died of tuberculosis in Cambridge, on 13 September 1940. == Publications == During his short lifetim...	{ "page_id": 40902897, "title": "Myron Mathisson" }
dynamics". Mathematical Proceedings of the Cambridge Philosophical Society. 36 (3): 331–350. Bibcode:1940PCPS...36..331M. doi:10.1017/S0305004100017370. S2CID 122742158. — (1942). "Relativistic dynamics of a spinning magnetic particle". Mathematical Proceedings of the Cambridge Philosophical Society. 38 (1): 40–60. Bib...	{ "page_id": 40902897, "title": "Myron Mathisson" }
A genomic island (GI) is part of a genome that has evidence of horizontal origins. The term is usually used in microbiology, especially with regard to bacteria. A GI can code for many functions, can be involved in symbiosis or pathogenesis, and may help an organism's adaptation. Many sub-classes of GIs exist that are b...	{ "page_id": 4530419, "title": "Genomic island" }
region was present in the common ancestor but has been lost in all the other species being compared, or (ii) that the region was absent in the common ancestor but was acquired through mutation and selection in the species in which it is still found. The argument for multiple deletions of the region would be strengthene...	{ "page_id": 4530419, "title": "Genomic island" }
Massive parallel signature sequencing (MPSS) is a procedure that is used to identify and quantify mRNA transcripts, resulting in data similar to serial analysis of gene expression (SAGE), although it employs a series of biochemical and sequencing steps that are substantially different. == How it works == MPSS is a meth...	{ "page_id": 23929075, "title": "Massively parallel signature sequencing" }
the specific signature sequence. The microbeads are then arrayed in a flow cell for sequencing and quantification. The sequence signatures are deciphered by the parallel identification of four bases by hybridization to fluorescently labeled encoders (Figure 5). Each of the encoders has a unique label which is detected ...	{ "page_id": 23929075, "title": "Massively parallel signature sequencing" }
gene expression". Frontiers in Bioscience. 14 (14): 552–69. doi:10.2741/3262. PMID 19273085. Reinartz, J; Bruyns, E; Lin, JZ; et al. (February 2002). "Massively parallel signature sequencing (MPSS) as a tool for in-depth quantitative gene expression profiling in all organisms". Brief Funct Genomic Proteomic. 1: 95–104....	{ "page_id": 23929075, "title": "Massively parallel signature sequencing" }
The molecular formula C6H5N3O4 may refer to: Dinitroanilines 2,3-Dinitroaniline 2,4-Dinitroaniline 2,5-Dinitroaniline 2,6-Dinitroaniline 3,4-Dinitroaniline 3,5-Dinitroaniline	{ "page_id": 60301558, "title": "C6H5N3O4" }
Oceanography and Marine Biology: An Annual Review is an annual review of oceanography and marine biology that has been published since 1963. It was originally edited by Harold Barnes. It was originally published by Aberdeen University Press and Allen & Unwin but is now published by CRC Press, part of Taylor & Francis. ...	{ "page_id": 58990845, "title": "Oceanography and Marine Biology: An Annual Review" }
The Leblanc process was an early industrial process for making soda ash (sodium carbonate) used throughout the 19th century, named after its inventor, Nicolas Leblanc. It involved two stages: making sodium sulfate from sodium chloride, followed by reacting the sodium sulfate with coal and calcium carbonate to make sodi...	{ "page_id": 598272, "title": "Leblanc process" }
see industrial history below. == Chemistry == In the first step, sodium chloride is treated with sulfuric acid in the Mannheim process. This reaction produces sodium sulfate (called the salt cake) and hydrogen chloride: 2 NaCl + H2SO4 → Na2SO4 + 2 HCl This chemical reaction had been discovered in 1772 by the Swedish ch...	{ "page_id": 598272, "title": "Leblanc process" }
The hydrogen chloride gas bubbles off and was discarded to atmosphere before gas absorption towers were introduced. This continues until all that is left is a fused mass. This mass still contains enough chloride to contaminate the later stages of the process. The mass is then exposed to direct flame, which evaporates n...	{ "page_id": 598272, "title": "Leblanc process" }
== Industrial history == Leblanc established the first Leblanc process plant in 1791 in St. Denis. However, French Revolutionaries seized the plant, along with the rest of Louis Philip's estate, in 1794, and publicized Leblanc's trade secrets. Napoleon I returned the plant to Leblanc in 1801, but lacking the funds to r...	{ "page_id": 598272, "title": "Leblanc process" }
this Solvay process was calcium chloride, and so it was both more economical and less polluting than the Leblanc method. From the late 1870s, Solvay-based soda works on the European continent provided stiff competition in their home markets to the Leblanc-based British soda industry. Additionally the Brunner Mond Solva...	{ "page_id": 598272, "title": "Leblanc process" }
ash, the process produced 5.5 tons of hydrogen chloride and 7 tons of calcium sulfide waste. This solid waste (known as galligu) had no economic value, and was piled in heaps and spread on fields near the soda works, where it weathered to release hydrogen sulfide, the toxic gas responsible for the odor of rotten eggs. ...	{ "page_id": 598272, "title": "Leblanc process" }
off hot noxious chemicals. Sometimes, workmen cleaning the reaction products out of the reverberatory furnace wore cloth mouth-and-nose gags to keep dust and aerosols out of the lungs. This improved somewhat later as processes were more heavily mechanised to improve economics and uniformity of product. By the 1880s, me...	{ "page_id": 598272, "title": "Leblanc process" }
Soda-lime glass	{ "page_id": 598272, "title": "Leblanc process" }
Developmental biology is the study of the process by which animals and plants grow and develop. Developmental biology also encompasses the biology of regeneration, asexual reproduction, metamorphosis, and the growth and differentiation of stem cells in the adult organism. == Perspectives == The main processes involved ...	{ "page_id": 8449, "title": "Developmental biology" }
inductive signals and the genes involved are different from those that control animal development. === Generative biology === Generative biology is the generative science that explores the dynamics guiding the development and evolution of a biological morphological form. == Developmental processes == === Cell different...	{ "page_id": 8449, "title": "Developmental biology" }
free living animals. In particular four models have been the subject of much investigation. Two of these have the ability to regenerate whole bodies: Hydra, which can regenerate any part of the polyp from a small fragment, and planarian worms, which can usually regenerate both heads and tails. Both of these examples ha...	{ "page_id": 8449, "title": "Developmental biology" }
same size. They are called cleavage divisions. Mouse epiblast primordial germ cells (see Figure: "The initial stages of human embryogenesis") undergo extensive epigenetic reprogramming. This process involves genome-wide DNA demethylation, chromatin reorganization and epigenetic imprint erasure leading to totipotency. D...	{ "page_id": 8449, "title": "Developmental biology" }
the cells of each germ layer move to form sheets such that the ectoderm ends up on the outside, mesoderm in the middle, and endoderm on the inside. Morphogenetic movements not only change the shape and structure of the embryo, but by bringing cell sheets into new spatial relationships they also make possible new phases...	{ "page_id": 8449, "title": "Developmental biology" }
and certain insects which hatch as a larva and then become remodeled to the adult form during a pupal stage. All the developmental processes listed above occur during metamorphosis. Examples that have been especially well studied include tail loss and other changes in the tadpole of the frog Xenopus, and the biology of...	{ "page_id": 8449, "title": "Developmental biology" }
first root, while the other end forms the tip of the shoot. In seed plants, the embryo will develop one or more "seed leaves" (cotyledons). By the end of embryogenesis, the young plant will have all the parts necessary to begin its life. Once the embryo germinates from its seed or parent plant, it begins to produce add...	{ "page_id": 8449, "title": "Developmental biology" }
dormancy, and other metabolic conditions; photoperiod, drought, temperature, and other external environmental conditions; and exogenous sources of PGRs, e.g., externally applied and of rhizospheric origin. === Morphological variation === Plants exhibit natural variation in their form and structure. While all organisms ...	{ "page_id": 8449, "title": "Developmental biology" }
In early development different vertebrate species all use essentially the same inductive signals and the same genes encoding regional identity. Even invertebrates use a similar repertoire of signals and genes although the body parts formed are significantly different. Model organisms each have some particular experimen...	{ "page_id": 8449, "title": "Developmental biology" }
A pet cemetery is a cemetery for pets. Although the veneration and burial of beloved pets has been practiced since ancient times, burial grounds reserved specifically for animals were not common until the late 19th century. == History == Many human cultures buried animal remains. For example, the Ancient Egyptians mumm...	{ "page_id": 860418, "title": "Pet cemetery" }
ones like Mariah Carey's cat Clarence and Ming the tiger. The site was listed on the National Register of Historic Places in 2012. Some other famous American pet cemeteries include Aspin Hill Memorial Park in Silver Spring, Maryland, believed to be the second-oldest in America, as well as the Pet Memorial Cemetery in C...	{ "page_id": 860418, "title": "Pet cemetery" }
The old quantum theory is a collection of results from the years 1900–1925, which predate modern quantum mechanics. The theory was never complete or self-consistent, but was instead a set of heuristic corrections to classical mechanics. The theory has come to be understood as the semi-classical approximation to modern ...	{ "page_id": 1188104, "title": "Old quantum theory" }
In 1913, Niels Bohr displayed rudiments of the later defined correspondence principle and used it to formulate a model of the hydrogen atom which explained the line spectrum. In the next few years Arnold Sommerfeld extended the quantum rule to arbitrary integrable systems making use of the principle of adiabatic invari...	{ "page_id": 1188104, "title": "Old quantum theory" }
later. In 1926 Erwin Schrödinger found a completely quantum mechanical wave-equation, which reproduced all the successes of the old quantum theory without ambiguities and inconsistencies. Schrödinger's wave mechanics developed separately from matrix mechanics until Schrödinger and others proved that the two methods pre...	{ "page_id": 1188104, "title": "Old quantum theory" }
periods of the different motions do not have to be the same, they can even be incommensurate, but there must be a set of coordinates where the motion decomposes in a multi-periodic way. The motivation for the old quantum condition was the correspondence principle, complemented by the physical observation that the quant...	{ "page_id": 1188104, "title": "Old quantum theory" }
{1}{2}}\hbar \omega } from the results found with the help of quantum mechanics. This constant is neglected in the derivation of the old quantum theory, and its value cannot be determined using it. The thermal properties of a quantized oscillator may be found by averaging the energy in each of the discrete states assum...	{ "page_id": 1188104, "title": "Old quantum theory" }
also exponentially small. The change in energy with respect to temperature is the specific heat, so the specific heat is exponentially small at low temperatures, going to zero like exp ⁡ ( − ℏ ω / k T ) {\displaystyle \exp(-\hbar \omega /kT)} At small values of β {\displaystyle \beta } , at high temperatures, the avera...	{ "page_id": 1188104, "title": "Old quantum theory" }
quantized. This was the first application of quantum theory to mechanical systems. A short while later, Peter Debye gave a quantitative theory of solid specific heats in terms of quantized oscillators with various frequencies (see Einstein solid and Debye model). === One-dimensional potential: U = 0 === One-dimensional...	{ "page_id": 1188104, "title": "Old quantum theory" }
F}=nh} which determines the energy levels, E n = ( 3 n h F 4 2 m ) 2 / 3 {\displaystyle E_{n}=\left({3nhF \over 4{\sqrt {2m}}}\right)^{2/3}} In the specific case F=mg, the particle is confined by the gravitational potential of the earth and the "wall" here is the surface of the earth. === One-dimensional potential: U =...	{ "page_id": 1188104, "title": "Old quantum theory" }
rotator can be described by two angles — θ {\displaystyle \theta } and ϕ {\displaystyle \phi } , where θ {\displaystyle \theta } is the inclination relative to an arbitrarily chosen z-axis while ϕ {\displaystyle \phi } is the rotator angle in the projection to the x–y plane. The kinetic energy is again the only contrib...	{ "page_id": 1188104, "title": "Old quantum theory" }
quantum mechanics, but in the era of the old quantum theory it led to a paradox: how can the orientation of the angular momentum relative to the arbitrarily chosen z-axis be quantized? This seems to pick out a direction in space. This phenomenon, the quantization of angular momentum about an axis, was given the name sp...	{ "page_id": 1188104, "title": "Old quantum theory" }
energy in combination with l {\displaystyle l} . The energy is: E = − 1 2 ( k + l ) 2 {\displaystyle E=-{1 \over 2(k+l)^{2}}} and it only depends on the sum of k and l, which is the principal quantum number n. Since k is positive, the allowed values of l for any given n are no bigger than n. The energies reproduce thos...	{ "page_id": 1188104, "title": "Old quantum theory" }
energy form a four-vector, as do the frequency and wave-number. In 1924, as a PhD candidate, Louis de Broglie proposed a new interpretation of the quantum condition. He suggested that all matter, electrons as well as photons, are described by waves obeying the relations. p = ℏ k {\displaystyle p=\hbar k} or, expressed ...	{ "page_id": 1188104, "title": "Old quantum theory" }
wave equation which matched the Hamilton–Jacobi equation for the phase; this is now known as the Schrödinger equation. == Kramers transition matrix == The old quantum theory was formulated only for special mechanical systems which could be separated into action angle variables which were periodic. It did not deal with ...	{ "page_id": 1188104, "title": "Old quantum theory" }
effect (that is, where the spin of the electron cannot be neglected). It cannot quantize "chaotic" systems, i.e. dynamical systems in which trajectories are neither closed nor periodic and whose analytical form does not exist. This presents a problem for systems as simple as a 2-electron atom which is classically chaot...	{ "page_id": 1188104, "title": "Old quantum theory" }
Polyetherketoneketone (PEKK) is a semi-crystalline thermoplastic in the polyaryletherketone (PAEK) family of polymers. It possesses high heat, chemical, and mechanical load resistance. PEKK has a glass transition temperature (Tg) of 162 °C. == Applications == Hexcel Corporation (Formerly Oxford Performance Materials) m...	{ "page_id": 38805770, "title": "Polyetherketoneketone" }
In 2017, the Kenya Nuclear Electrification Board (Kneb) estimated that a 1,000 MW nuclear plant could be operational by 2027 and cost Ksh500-600 billion (US$5-$6 billion), to be located near a large body of water, such as the Indian Ocean, Lake Victoria or Lake Turkana. == Background == In September 2010 Former Energy ...	{ "page_id": 31990026, "title": "Nuclear power in Kenya" }
Astrobotany is an applied sub-discipline of botany that is the study of plants in space environments. It is a branch of astrobiology and botany. Astrobotany concerns both the study of extraterrestrial vegetation discovery, as well as research into the growth of terrestrial vegetation in outer space by humans. It has be...	{ "page_id": 10494220, "title": "Astrobotany" }
radiating from Earth as evidence of "widespread biological activity" on earth, with evidence of photosynthesis a particularly strong factor. The increase-in-strength of Earth's VRE biosignature has been assessed through modelling of early Earth radiation. Mosses and ferns, which were dominant on Earth in the Ordovician...	{ "page_id": 10494220, "title": "Astrobotany" }
use atmospheric measurements to determine the level of atmospheric oxygen, which if high would rule out surface abundance of non-oxidised minerals. === Vegetation searches === Dubbed ‘the creator of astrobotany’, Gavriil Adrianovich Tikhov coined the term in 1945 to describe the emerging field surrounding the search fo...	{ "page_id": 10494220, "title": "Astrobotany" }
James Webb Space Telescope has been searching the TRAPPIST-1 exoplanet system since 2021 for signs of extraterrestrial vegetation through capturing atmospheric data, including a VRE biosignature, that is made visible when TRAPPIST-1's exoplanets pass across the face of the star. NASA have judged three of TRAPPIST-1's r...	{ "page_id": 10494220, "title": "Astrobotany" }
the challenges of creating life support systems both in space and on other planets, primarily Mars. == History == Russian scientist Konstantin Tsiolkovsky was one of the first people to discuss using photosynthetic life as a resource in space agricultural systems. Speculation about plant cultivation in space has been a...	{ "page_id": 10494220, "title": "Astrobotany" }
station Mir. Bion 5 carried Daucus carota and Bion 7 carried maize (aka corn). Plant research continued on the International Space Station. Biomass Production System was used on the ISS Expedition 4. The Vegetable Production System (Veggie) system was later used aboard ISS. Plants tested in Veggie before going into spa...	{ "page_id": 10494220, "title": "Astrobotany" }
Chlorella, Anacystis, Synechocystis, Scenedesmus, Synechococcus, and Spirulina species to study how photosynthetic organisms could be used for O2 and CO2 cycling in closed systems. Later research through Russia's BIOS program and the US's CELSS program investigated the use of higher plants to fulfill the roles of atmos...	{ "page_id": 10494220, "title": "Astrobotany" }
resources base, potentially mining frozen water and carbon dioxide from the surface and eventually using hollowed craters for autonomous growth chambers that can be harvested during mining missions. == Plant research == The study of plant research has yielded information useful to other areas of botany and horticulture...	{ "page_id": 10494220, "title": "Astrobotany" }
the ESA's European Modular Cultivation System enables experimentation with plant growth; acting as a miniature greenhouse, scientists aboard the International Space Station can investigate how plants react in variable-gravity conditions. The Gravi-1 experiment (2008) utilized the EMCS to study lentil seedling growth an...	{ "page_id": 10494220, "title": "Astrobotany" }
of Pandora. The 2011 book and 2015 film The Martian by Andy Weir highlights the heroic survival of botanist Mark Watney, who uses his horticultural background to grow potatoes for food while trapped on Mars. == See also == Bioastronautics – Academic discipline Biolab – Science payload fitted inside the Columbus laborat...	{ "page_id": 10494220, "title": "Astrobotany" }
LabelMe is a project created by the MIT Computer Science and Artificial Intelligence Laboratory (CSAIL) that provides a dataset of digital images with annotations. The dataset is dynamic, free to use, and open to public contribution. The most applicable use of LabelMe is in computer vision research. As of October 31, 2...	{ "page_id": 14622989, "title": "LabelMe" }
anonymously or by logging into a free account. To access the tool, users must have a compatible web browser with JavaScript support. When the tool is loaded, it chooses a random image from the LabelMe dataset and displays it on the screen. If the image already has object labels associated with it, they will be overlaid...	{ "page_id": 14622989, "title": "LabelMe" }
problems. Some are inherent in the data, such as the objects in the images not being uniformly distributed with respect to size and image location. This is due to the images being primarily taken by humans who tend to focus the camera on interesting objects in a scene. However, cropping and rescaling the images randoml...	{ "page_id": 14622989, "title": "LabelMe" }
data, the object class dog at the abstract level should incorporate all of these text labels. WordNet is a database of words organized into a structural way. It allows assigning a word to a category, or in WordNet language: a sense. Sense assignment is not easy to do automatically. When the authors of LabelMe tried aut...	{ "page_id": 14622989, "title": "LabelMe" }

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