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rely on biological signals of reproductive success and non-biological signals, such as the female's willingness to marry. Unlike many animals, humans are not able to consciously display physical changes to their body when they are ready to mate, so they have to rely on other forms of communication before engaging in a ...	{ "page_id": 70324833, "title": "Mate choice in humans" }
to disease-resistance and high estrogen levels, which are factors that suggest reproductive value to a potential mate. Physical beauty: Observable characteristics of a woman can indicate good health and the ability to reproduce, qualities which are likely to be desired by a male. This may include smooth skin, absence o...	{ "page_id": 70324833, "title": "Mate choice in humans" }
had brighter plumage (feathers). In addition, Hamilton and Zuk showed that, comparing across multiple species, there is greater selection for physical attributes in species under greater parasitic stress. This has influenced research regarding human mate choice. In societies with a high prevalence of parasites or patho...	{ "page_id": 70324833, "title": "Mate choice in humans" }
areas such as the voice, face and body shape of males. The face, in particular, may hold several cues for parasitic resistance and has been the subject of most attractiveness research. Polygamy: Tropical areas were originally associated with polygynous societies as a result of the surrounding environment being both eco...	{ "page_id": 70324833, "title": "Mate choice in humans" }
it is unknown why women on contraceptive pills rate smell in this way. It was found that when processing MHC-similar smells were processed faster. Contrary to these findings, other studies have found that there is no correlation between attraction and odor by testing males' odor preferences on women's odors. The study ...	{ "page_id": 70324833, "title": "Mate choice in humans" }
divergence in the mate choice with accordance to HLA genotyping. Additional studies have been conducted simultaneously on African and European populations that only show correlation of MHC divergence in European but not African populations. == See also == Human mating strategies Mating preferences == References ==	{ "page_id": 70324833, "title": "Mate choice in humans" }
The Canberra Ornithologists Group (COG) was founded on 15 April 1970 when the ACT branch of the Royal Australasian Ornithologists Union (RAOU) became defunct following drastic reform within the RAOU in the late 1960s which abolished all its branches. It publishes a quarterly journal, Canberra Bird Notes, as well as a m...	{ "page_id": 7803491, "title": "Canberra Ornithologists Group" }
In mathematics, the Gibbons–Hawking ansatz is a method of constructing gravitational instantons introduced by Gary Gibbons and Stephen Hawking (1978, 1979). It gives examples of hyperkähler manifolds in dimension 4 that are invariant under a circle action. == Description == Suppose that U {\displaystyle U} is an open s...	{ "page_id": 35132005, "title": "Gibbons–Hawking ansatz" }
} {\displaystyle U=\mathbb {R} ^{3}\setminus \{0\}} and the harmonic function V ( x ) = 1 2 \| x \| {\displaystyle V(x)={\frac {1}{2\|x\|}}} . === ALE gravitational instantons === The ALE gravitational instanton of type A k − 1 {\displaystyle A_{k-1}} can be obtained by applying the Gibbons-Hawking ansatz to the open subse...	{ "page_id": 35132005, "title": "Gibbons–Hawking ansatz" }
The geologic record in stratigraphy, paleontology and other natural sciences refers to the entirety of the layers of rock strata. That is, deposits laid down by volcanism or by deposition of sediment derived from weathering detritus (clays, sands etc.). This includes all its fossil content and the information it yields...	{ "page_id": 18092646, "title": "Geologic record" }
thoroughly support the law of superposition. However using broadly occurring deposited layers trapped within differently located rock columns, geologists have pieced together a system of units covering most of the geologic time scale using the law of superposition, for where tectonic forces have uplifted one ridge newl...	{ "page_id": 18092646, "title": "Geologic record" }
missing there. This is one form of discordancy and the means geologists use to compensate for local variations in the rock record. With the two remaining marker species it is possible to correlate rock layers of the same age (early Eocene and latter part of the middle Eocene) in both South Carolina and Virginia, and th...	{ "page_id": 18092646, "title": "Geologic record" }
The history of loop quantum gravity spans more than three decades of intense research. == History == === Classical theories of gravitation === General relativity is the theory of gravitation published by Albert Einstein in 1915. According to it, the force of gravity is a manifestation of the local geometry of spacetime...	{ "page_id": 856680, "title": "History of loop quantum gravity" }
way to write down the two constraints of the ADM Hamiltonian formulation of general relativity in terms of these spinorial connections. In his form, the constraints are simply conditions that the spinorial Weyl curvature is trace free and symmetric. He also discovered the presence of new constraints which he suggested ...	{ "page_id": 856680, "title": "History of loop quantum gravity" }
in which the Wheeler–DeWitt equation was written in terms of a well-defined Hamiltonian operator on a well-defined Hilbert space was obtained. This led to the construction of the first known exact solution, the so-called Chern–Simons form or Kodama state. The physical interpretation of this state remains obscure. In 19...	{ "page_id": 856680, "title": "History of loop quantum gravity" }
theory." The present version of the covariant dynamics is due to the convergent work of different groups, but it is commonly named after a paper by Jonathan Engle, Roberto Pereira and Carlo Rovelli in 2007–08. Heuristically, it would be expected that evolution between spin network states might be described by discrete ...	{ "page_id": 856680, "title": "History of loop quantum gravity" }
and Javier P. Muniain, Gauge Fields, Knots and Quantum Gravity, World Scientific (1994). Carlo Rovelli, "A Dialog on Quantum Gravity," e-print available as hep-th/0310077. More advanced introductory/expository works Carlo Rovelli, Quantum Gravity, Cambridge University Press (2004); draft available online. Thomas Thiema...	{ "page_id": 856680, "title": "History of loop quantum gravity" }
The British Oceanographic Data Centre (BODC) is a national facility in the United Kingdom that collects and distributes marine environmental data. It serves as the designated marine science data centre for the UK and is part of the National Oceanography Centre (NOC). Most of its operations are conducted at its Liverpoo...	{ "page_id": 19075690, "title": "British Oceanographic Data Centre" }
and archiving data from tide gauges around the UK coast for the National Tide Gauge Network, which aims to obtain high quality tidal information and to provide warning of possible flooding of coastal areas around the British Isles. This is part of the National Tidal & Sea Level Facility (NTSLF) Hosting the Marine Envir...	{ "page_id": 19075690, "title": "British Oceanographic Data Centre" }
Playing God refers to assuming powers of decision, intervention, or control metaphorically reserved to God. Acts described as playing God may include, for example, deciding who should live or die in a situation where not everyone can be saved, the use and development of biotechnologies such as synthetic biology, and in...	{ "page_id": 4395638, "title": "Playing God (ethics)" }
which have been considered to be attempted acts of playing God. Biomedical projects such as the attempted creation of artificial sperm and the creation of artificial life itself have brought the sci-fi stories of the 1900s out of fantasy and closer to reality. Other projects scientists have attempted include cloning (D...	{ "page_id": 4395638, "title": "Playing God (ethics)" }
God", such as the Confucianism school of thought. This provides another angle of analysis that can be offered towards this complicated matter. ==== In genetic modification ==== There is a strong debate regarding morality and the consequences of science and playing God. Gene editing is a big topic that has been the cent...	{ "page_id": 4395638, "title": "Playing God (ethics)" }
special trait of technological advancement. A common argument against genetic editing especially that of children is the designer baby argument. Designer babies would be children who have been created to be stronger, smarter, possibly more attractive, and with many other desirable traits. This would be a technology tha...	{ "page_id": 4395638, "title": "Playing God (ethics)" }
focusing on climate engineering and changing the very critical environment that God has provided, we, humans, need to be aware of the possible negative outcomes that can arise when engineering our climate. We need to be ready for anything. One must think about who the vulnerable people are, that are going to be affecte...	{ "page_id": 4395638, "title": "Playing God (ethics)" }
Stanford University, suggest that instead of abandoning the idea due to risk, there should be continued research for the consequences of geo-engineering so that the exact probabilities and effects of consequences are understood. Scientists also argue that geo-engineering in some instances can be cheaper and quite finan...	{ "page_id": 4395638, "title": "Playing God (ethics)" }
journalists to refer to things they disagree with. Alexandre Erler, in response to Ball, has argued that while the phrase is not meaningless, it is extremely vague and requires further clarification for it to be useful within the context of an argument. === The transhumanist objection === == See also == == Notes == == ...	{ "page_id": 4395638, "title": "Playing God (ethics)" }
Statistical learning theory is a framework for machine learning drawing from the fields of statistics and functional analysis. Statistical learning theory deals with the statistical inference problem of finding a predictive function based on data. Statistical learning theory has led to successful applications in fields...	{ "page_id": 1053303, "title": "Statistical learning theory" }
set data, that function is validated on a test set of data, data that did not appear in the training set. == Formal description == Take X {\displaystyle X} to be the vector space of all possible inputs, and Y {\displaystyle Y} to be the vector space of all possible outputs. Statistical learning theory takes the perspec...	{ "page_id": 1053303, "title": "Statistical learning theory" }
is defined to be I [ f ] = ∫ X × Y V ( f ( x ) , y ) p ( x , y ) d x d y {\displaystyle I[f]=\int _{X\times Y}V(f(\mathbf {x} ),y)\,p(\mathbf {x} ,y)\,d\mathbf {x} \,dy} The target function, the best possible function f {\displaystyle f} that can be chosen, is given by the f {\displaystyle f} that satisfies f = argmin ...	{ "page_id": 1053303, "title": "Statistical learning theory" }
) 2 {\displaystyle V(f(\mathbf {x} ),y)=(y-f(\mathbf {x} ))^{2}} The absolute value loss (also known as the L1-norm) is also sometimes used: V ( f ( x ) , y ) = \| y − f ( x ) \| {\displaystyle V(f(\mathbf {x} ),y)=\|y-f(\mathbf {x} )\|} === Classification === In some sense the 0-1 indicator function is the most natural lo...	{ "page_id": 1053303, "title": "Statistical learning theory" }
{H}}} to linear functions: this can be seen as a reduction to the standard problem of linear regression. H {\displaystyle {\mathcal {H}}} could also be restricted to polynomial of degree p {\displaystyle p} , exponentials, or bounded functions on L1. Restriction of the hypothesis space avoids overfitting because the fo...	{ "page_id": 1053303, "title": "Statistical learning theory" }
e − n ϵ 2 / 8 {\displaystyle \mathbb {P} {\bigg (}\sup _{f\in {\mathcal {F}}}\|{\hat {R}}(f)-R(f)\|\geq \epsilon {\bigg )}\leq 2S({\mathcal {F}},n)e^{-n\epsilon ^{2}/8}\approx n^{d}e^{-n\epsilon ^{2}/8}} where S ( F , n ) {\displaystyle S({\mathcal {F}},n)} is the shattering number and n {\displaystyle n} is the number o...	{ "page_id": 1053303, "title": "Statistical learning theory" }
Chromatin bridge is a mitotic occurrence that forms when telomeres of sister chromatids fuse together and fail to completely segregate into their respective daughter cells. Because this event is most prevalent during anaphase, the term anaphase bridge is often used as a substitute. After the formation of individual dau...	{ "page_id": 33231480, "title": "Chromatin bridge" }
either in an end-to-end manner or through topological entrapment (e.g., catenation or unresolved DNA cross-links), have also been associated with chromatin bridge formation. When viewed under a fluorescence microscope and immunostained for cytological markers, these chromatin bridges appear to emanate from either centr...	{ "page_id": 33231480, "title": "Chromatin bridge" }
another, even after mitosis. A chromatin bridge may also be observed using indirect immunofluorescence, in which anti-tubulin emits a green coloration when bound to microtubules in the presence of UV light. Because microtubules maintain the positions of the chromosomes during mitosis, they appear to be densely pinched ...	{ "page_id": 33231480, "title": "Chromatin bridge" }
Kojic acid is an organic compound with the formula HOCH2C5H2O2OH. It is a derivative of 4-pyrone that functions in nature as a chelation agent produced by several species of fungus, especially Aspergillus oryzae, which has the Japanese common name koji. Kojic acid is a by-product in the fermentation process of malting ...	{ "page_id": 5116536, "title": "Kojic acid" }
Safety MSDS data Mohajer, Fatemeh; Mohammadi Ziarani, Ghodsi (2021). "An Overview of Quantitative and Qualitative Approaches on the Synthesis of Heterocyclic Kojic Acid Scaffolds through the Multi-Component Reactions". Heterocycles. 102 (2). Japan Institute of Heterocyclic Chemistry: 211. doi:10.3987/REV-20-936.	{ "page_id": 5116536, "title": "Kojic acid" }
Peptidyl-L-lysine(-L-arginine) hydrolase may refer to: Lysine carboxypeptidase, an enzyme Carboxypeptidase E, an enzyme	{ "page_id": 39260790, "title": "Peptidyl-L-lysine(-L-arginine) hydrolase" }
Instrumental analysis is a field of analytical chemistry that investigates analytes using scientific instruments. == Spectroscopy == Spectroscopy measures the interaction of the molecules with electromagnetic radiation. Spectroscopy consists of many different applications such as atomic absorption spectroscopy, atomic ...	{ "page_id": 26219128, "title": "Instrumental chemistry" }
thermogravimetric analysis measure the interaction of a material and heat. == Separation == Separation processes are used to decrease the complexity of material mixtures. Chromatography and electrophoresis are representative of this field. == Hybrid techniques == Combinations of the above techniques produce "hybrid" or...	{ "page_id": 26219128, "title": "Instrumental chemistry" }
Incipient wetness impregnation (IW or IWI), also called capillary impregnation or dry impregnation, is a commonly used technique for the synthesis of heterogeneous catalysts. Typically, the active metal precursor is dissolved in an aqueous or organic solution. Then the metal-containing solution is added to a catalyst s...	{ "page_id": 7737980, "title": "Incipient wetness impregnation" }
This article includes a list of the most massive known objects of the Solar System and partial lists of smaller objects by observed mean radius. These lists can be sorted according to an object's radius and mass and, for the most massive objects, volume, density, and surface gravity, if these values are available. Thes...	{ "page_id": 594550, "title": "List of Solar System objects by size" }
their rotation, and can sometimes even have quite different equatorial diameters (scalene ellipsoids such as Haumea). Unlike bodies such as Haumea, the irregular bodies have a significantly non-ellipsoidal profile, often with sharp edges. There can be difficulty in determining the diameter (within a factor of about 2) ...	{ "page_id": 594550, "title": "List of Solar System objects by size" }
uncertainties in the figures for mass and radius, and irregularities in the shape and density, with accuracy often depending on how close the object is to Earth or whether it has been visited by a probe. == Graphical overview == == Objects with radii over 400 km == The following objects have a nominal mean radius of 40...	{ "page_id": 594550, "title": "List of Solar System objects by size" }
(1–1.2 g/cm3), implying that the objects retain significant internal porosity from their formation and were never gravitationally compressed into fully solid bodies. === From 100 to 199 km === This list contains a selection of objects estimated to be between 100 and 199 km in radius (200 and 399 km in diameter). The la...	{ "page_id": 594550, "title": "List of Solar System objects by size" }
mass values of asteroids are assumed. === From 1 to 19 km === This list contains some examples of Solar System objects between 1 and 19 km in radius. This is a common size for asteroids, comets and irregular moons. === Below 1 km === This list contains examples of objects below 1 km in radius. That means that irregular...	{ "page_id": 594550, "title": "List of Solar System objects by size" }
References == == Further reading == NASA Planetary Data System (PDS) Asteroids with Satellites Minor Planet discovery circumstances Supplemental IRAS Minor Planet Survey (SIMPS) and IRAS Minor Planet Survey (IMPS) SIMPS & IMPS (V6, additional, from here) Asteroid Data Archive Archive Planetary Science Institute == Exte...	{ "page_id": 594550, "title": "List of Solar System objects by size" }
In quantum mechanics, Bargmann's limit, named for Valentine Bargmann, provides an upper bound on the number N ℓ {\displaystyle N_{\ell }} of bound states with azimuthal quantum number ℓ {\displaystyle \ell } in a system with central potential V {\displaystyle V} . It takes the form N ℓ < 1 2 ℓ + 1 2 m ℏ 2 ∫ 0 ∞ r \| V (...	{ "page_id": 1184376, "title": "Bargmann's limit" }
d r < + ∞ , {\displaystyle \int _{0}^{+\infty }r\|V(r)\|dr<+\infty ,} then the number of bound states N ℓ {\displaystyle N_{\ell }} with azimuthal quantum number ℓ {\displaystyle \ell } for a particle of mass m {\displaystyle m} obeying the corresponding Schrödinger equation, is bounded from above by N ℓ < 1 2 ℓ + 1 2 m ...	{ "page_id": 1184376, "title": "Bargmann's limit" }
r 2 ϕ 0 ℓ ( r ) = − W ( r ) ϕ 0 ℓ ( r ) , {\displaystyle {\frac {d^{2}}{dr^{2}}}\phi _{0\ell }(r)-{\frac {\ell (\ell +1)}{r^{2}}}\phi _{0\ell }(r)=-W(r)\phi _{0\ell }(r),} with W = 2 m \| V \| / ℏ 2 {\displaystyle W=2m\|V\|/\hbar ^{2}} . By applying variation of parameters, one can obtain the following implicit solution ϕ ...	{ "page_id": 1184376, "title": "Bargmann's limit" }
2 ℓ + 1 ) ≥ N ℓ ( 2 ℓ + 1 ) , {\displaystyle {\frac {2m}{\hbar ^{2}}}\int _{0}^{+\infty }r\|V(r)\|dr\geq {\frac {2m}{\hbar ^{2}}}\int _{0}^{\nu _{N}}r\|V(r)\|dr>N(2\ell +1)\geq N_{\ell }(2\ell +1),} proving Bargmann's limit. Note that as the integral on the right is assumed to be finite, so must be N {\displaystyle N} and ...	{ "page_id": 1184376, "title": "Bargmann's limit" }
"The Platonic Permutation" is the ninth episode of the ninth season of The Big Bang Theory. The 192nd episode overall, it first aired on CBS on November 19, 2015. The story follows the characters throughout Thanksgiving. The first storyline explores Sheldon and Amy's relationship as they meet-up, after being broken up....	{ "page_id": 58593920, "title": "The Platonic Permutation" }
she only disclosed in her journal. To apologize for reading it without permission, Leonard dances in the lingerie, asking Penny to post an image of him onto her social media as punishment. Howard, Raj, Bernadette, and Emily arrive at the apartment around this time, to Leonard's embarrassment. Later, Amy tells Sheldon s...	{ "page_id": 58593920, "title": "The Platonic Permutation" }
the other two subplots had "left something to be desired". Digital Spy's Tom Eames said of "The Platonic Permutation": "Aside from a couple of sweet scenes with Sheldon and Amy, this was one of those episodes where you'd have a better time if you just looked at the photos and caught up on the synopsis on Wikipedia". Sc...	{ "page_id": 58593920, "title": "The Platonic Permutation" }
have been given to this storyline calling the other two "lazy and boring". === Awards === At the Art Directors Guild Awards 2015, John Shaffner (production designer), along with Francoise Cherry-Cohen (set designer), and Ann Shea (set decorator) won the Excellence in Production Design Award - Multi-Camera Television Se...	{ "page_id": 58593920, "title": "The Platonic Permutation" }
In general, a sample is a limited quantity of something which is intended to be similar to and represent a larger amount of that thing(s). The things could be countable objects such as individual items available as units for sale, or an uncountable material. Even though the word "sample" implies a smaller quantity take...	{ "page_id": 10949251, "title": "Sample (material)" }
container of some sort. Where goods are sold or supplied by reference to a sample, relevant sale of goods legislation may dictate the supplier's legal obligations in ensuring that the bulk of the goods corresponds with the goods comprising the sample, for example in the UK, the Sale of Goods Act 1979, section 15, the S...	{ "page_id": 10949251, "title": "Sample (material)" }
In statistical mechanics, the hard hexagon model is a 2-dimensional lattice model of a gas, where particles are allowed to be on the vertices of a triangular lattice but no two particles may be adjacent. The model was solved by Rodney Baxter (1980), who found that it was related to the Rogers–Ramanujan identities. == T...	{ "page_id": 20058756, "title": "Hard hexagon model" }
log ⁡ ( κ ) d z = z − 7 z 2 + 58 z 3 − 519 z 4 + 4856 z 5 + ⋯ . {\displaystyle \rho =z{\frac {d\log(\kappa )}{dz}}=z-7z^{2}+58z^{3}-519z^{4}+4856z^{5}+\cdots .} The vertices of the lattice fall into 3 classes numbered 1, 2, and 3, given by the 3 different ways to fill space with hard hexagons. There are 3 local densiti...	{ "page_id": 20058756, "title": "Hard hexagon model" }
4 ) ( 1 − x 6 n − 3 ) 2 ( 1 − x 6 n − 2 ) ( 1 − x 6 n − 5 ) ( 1 − x 6 n − 1 ) ( 1 − x 6 n ) 2 {\displaystyle \kappa ={\frac {H(x)^{3}Q(x^{5})^{2}}{G(x)^{2}}}\prod _{n\geq 1}{\frac {(1-x^{6n-4})(1-x^{6n-3})^{2}(1-x^{6n-2})}{(1-x^{6n-5})(1-x^{6n-1})(1-x^{6n})^{2}}}} ρ = ρ 1 = ρ 2 = ρ 3 = − x G ( x ) H ( x 6 ) P ( x 3 ) P...	{ "page_id": 20058756, "title": "Hard hexagon model" }
2 {\displaystyle \kappa =x^{-{\frac {1}{3}}}{\frac {G(x)^{3}Q(x^{5})^{2}}{H(x)^{2}}}\prod _{n\geq 1}{\frac {(1-x^{3n-2})(1-x^{3n-1})}{(1-x^{3n})^{2}}}} ρ 1 = H ( x ) Q ( x ) ( G ( x ) Q ( x ) + x 2 H ( x 9 ) Q ( x 9 ) ) Q ( x 3 ) 2 {\displaystyle \rho _{1}={\frac {H(x)Q(x)(G(x)Q(x)+x^{2}H(x^{9})Q(x^{9}))}{Q(x^{3})^{2}}...	{ "page_id": 20058756, "title": "Hard hexagon model" }
1999). == References == Andrews, George E. (1981), "The hard-hexagon model and Rogers-Ramanujan type identities", Proceedings of the National Academy of Sciences of the United States of America, 78 (9): 5290–5292, Bibcode:1981PNAS...78.5290A, doi:10.1073/pnas.78.9.5290, ISSN 0027-8424, MR 0629656, PMC 348728, PMID 1659...	{ "page_id": 20058756, "title": "Hard hexagon model" }
Missense mRNA is a messenger RNA bearing one or more mutated codons that yield polypeptides with an amino acid sequence different from the wild-type or naturally occurring polypeptide. Missense mRNA molecules are created when template DNA strands or the mRNA strands themselves undergo a missense mutation in which a pro...	{ "page_id": 10359432, "title": "Missense mRNA" }
can insert in place of A and T respectively. Ionizing radiation like x-rays and γ-rays can deaminate cytosine to uracil. Missense mRNAs may be applied synthetically in forward and reverse genetic screens used to interrogate the genome. Site-directed mutagenesis is a technique often employed to create knock-in and knock...	{ "page_id": 10359432, "title": "Missense mRNA" }
An electrostatic precipitator (ESP) is a filterless device that removes fine particles, such as dust and smoke, from a flowing gas using the force of an induced electrostatic charge minimally impeding the flow of gases through the unit. In contrast to wet scrubbers, which apply energy directly to the flowing fluid medi...	{ "page_id": 1839752, "title": "Electrostatic precipitator" }
for vitamins A and B1, among many others. Research Corporation set territories for manufacturers of this technology, which included Western Precipitation (Los Angeles), Lodge-Cottrell (England), Lurgi Apparatebau-Gesellschaft (Germany), and Japanese Cottrell Corp. (Japan), and was a clearinghouse for any process improv...	{ "page_id": 1839752, "title": "Electrostatic precipitator" }
stream flows horizontally through the spaces between the wires, and then passes through the stack of plates. A negative voltage of several thousand volts is applied between wire and plate. If the applied voltage is high enough, an electric corona discharge ionizes the air around the electrodes, which then ionizes the p...	{ "page_id": 1839752, "title": "Electrostatic precipitator" }
a precipitator can usually be done without interrupting the airflow. == Collection efficiency (R) == The following factors affect the efficiency of electrostatic precipitators: Larger collection-surface areas and lower gas-flow rates increase efficiency because of the increased time available for electrical activity to...	{ "page_id": 1839752, "title": "Electrostatic precipitator" }
functioning of ESPs. ESPs work best under normal resistivity conditions. Resistivity, which is a characteristic of particles in an electric field, is a measure of a particle's resistance to transferring charge (both accepting and giving up charges). Resistivity is a function of a particle's chemical composition as well...	{ "page_id": 1839752, "title": "Electrostatic precipitator" }
thickness of the dust layer. In high-resistance dust layers, the dust is not sufficiently conductive, so electrical charges have difficulty moving through the dust layer. Consequently, electrical charges accumulate on and beneath the dust layer surface, creating a strong electric field. Voltages can be greater than 10,...	{ "page_id": 1839752, "title": "Electrostatic precipitator" }
conduction on particles is closely related to surface-leakage currents occurring on electrical insulators, which have been extensively studied. An interesting practical application of surface-leakage is the determination of dew point by measurement of the current between adjacent electrodes mounted on a glass surface. ...	{ "page_id": 1839752, "title": "Electrostatic precipitator" }
builds up, and the electrical charges accumulate on the surface of the dust layer, the voltage difference between the discharge and collection electrodes decreases. The migration velocities of small particles are especially affected by the reduced electric field strength. Another problem that occurs with high resistivi...	{ "page_id": 1839752, "title": "Electrostatic precipitator" }
been observed with dust layers as thin as 0.1 mm, but a dust layer just over one particle thick can reduce the sparking voltage by 50%. The most marked effects of back corona on the current-voltage characteristics are: Reduction of the spark over voltage by as much as 50% or more; Current jumps or discontinuities cause...	{ "page_id": 1839752, "title": "Electrostatic precipitator" }
corona causing large amounts of current to surge through the (low resistivity) dust layer. The controls sense this surge as a spark. As precipitators are operated in spark-limiting mode, power is terminated and the corona generation cycle re-initiates. Thus, lower power (current) readings are noted with relatively high...	{ "page_id": 1839752, "title": "Electrostatic precipitator" }
theorized that ammonia reacts with H2SO4 contained in the flue gas to form an ammonium sulfate compound that increases the cohesivity of the dust. This additional cohesivity makes up for the loss of electrical attraction forces. The table below summarizes the characteristics associated with low, normal and high resisti...	{ "page_id": 1839752, "title": "Electrostatic precipitator" }
lists various conditioning agents and their mechanisms of operation. If injection of ammonium sulfate occurs at a temperature greater than about 600 °F (320 °C), dissociation into ammonia and sulfur trioxide results. Depending on the ash, SO2 may preferentially interact with fly ash as SO3 conditioning. The remainder r...	{ "page_id": 1839752, "title": "Electrostatic precipitator" }
(320 °F) which provides optimal resistivity of the coal-ash particles. For some difficult applications with low-sulfur fuel hot-end units have been built operating above 370 °C (698 °F). The original parallel plate–weighted wire design (see figure of Plate and Bar precipitator above) has evolved as more efficient (and ...	{ "page_id": 1839752, "title": "Electrostatic precipitator" }
messy to clean. A negative side-effect of electrostatic precipitation devices is the potential production of toxic ozone and NOx. However, electrostatic precipitators offer benefits over other air purifications technologies, such as HEPA filtration, which require expensive filters and can become "production sinks" for ...	{ "page_id": 1839752, "title": "Electrostatic precipitator" }
Plague is an infectious disease caused by the bacterium Yersinia pestis. Symptoms include fever, weakness and headache. Usually this begins one to seven days after exposure. There are three forms of plague, each affecting a different part of the body and causing associated symptoms. Pneumonic plague infects the lungs, ...	{ "page_id": 4746, "title": "Plague (disease)" }
headaches, and nausea. Many people experience swelling in their lymph nodes if they have bubonic plague. For those with pneumonic plague, symptoms may (or may not) include a cough, pain in the chest, and haemoptysis. === Bubonic plague === When a flea bites a human and contaminates the wound with regurgitated blood, th...	{ "page_id": 4746, "title": "Plague (disease)" }
white in the centre. Untreated, the septicemic plague is usually fatal. Early treatment with antibiotics reduces the mortality rate to between 4 and 15 per cent. === Pneumonic plague === The pneumonic form of plague arises from infection of the lungs. It causes coughing and thereby produces airborne droplets that conta...	{ "page_id": 4746, "title": "Plague (disease)" }
that infested the rats, making the rats themselves the first victims of the plague. Rodent-borne infection in a human occurs when a person is bitten by a flea that has been infected by biting a rodent that itself has been infected by the bite of a flea carrying the disease. The bacteria multiply inside the flea, sticki...	{ "page_id": 4746, "title": "Plague (disease)" }
reaction (PCR) may also be used to diagnose plague, by detecting the presence of bacterial genes such as the pla gene (plasmogen activator) and caf1 gene, (F1 capsule antigen). PCR testing requires a very small sample and is effective for both alive and dead bacteria. For this reason, if a person receives antibiotics b...	{ "page_id": 4746, "title": "Plague (disease)" }
between 1897 and 1925, reducing the plague mortality by 50–85%. Since human plague is rare in most parts of the world as of 2023, routine vaccination is not needed other than for those at particularly high risk of exposure, nor for people living in areas with enzootic plague, meaning it occurs at regular, predictable r...	{ "page_id": 4746, "title": "Plague (disease)" }
close (<6 feet) or direct contact with infected animals, such as veterinary staff, pet owners, and hunters. Specific recommendations on pre- and post-exposure prophylaxis are available in the clinical guidelines on treatment and prophylaxis of plague published in 2021. == Treatments == If diagnosed in time, the various...	{ "page_id": 4746, "title": "Plague (disease)" }
Kyrgyzstan, are closest to the strand found in the graves, suggesting this is also the location where plague transferred from animals to humans. == Biological weapon == The plague has a long history as a biological weapon. Historical accounts from ancient China and medieval Europe details the use of infected animal car...	{ "page_id": 4746, "title": "Plague (disease)" }
having spread bubonic plague within a 36-kilometre (22 mi) radius around the city of Changde. Ishii innovated bombs containing live mice and fleas, with very small explosive loads, to deliver the weaponized microbes, overcoming the problem of the explosive killing the infected animal and insect by the use of a ceramic,...	{ "page_id": 4746, "title": "Plague (disease)" }
A secondary carbon is a carbon atom bound to two other carbon atoms and has sp3 hybridization. For this reason, secondary carbon atoms are found in almost (neopentane, for example, does not have any secondary carbon atoms) all hydrocarbons having at least three carbon atoms. In unbranched alkanes, the inner carbon atom...	{ "page_id": 16913034, "title": "Secondary carbon" }
The balance of nature, also known as ecological balance, is a theory that proposes that ecological systems are usually in a stable equilibrium or homeostasis, which is to say that a small change (the size of a particular population, for example) will be corrected by some negative feedback that will bring the parameter ...	{ "page_id": 19468941, "title": "Balance of nature" }
of nature concept once ruled ecological research and governed the management of natural resources. This led to a doctrine popular among some conservationists that nature was best left to its own devices, and that human intervention into it was by definition unacceptable. The theory was a central theme in the 1962 book ...	{ "page_id": 19468941, "title": "Balance of nature" }
is incompatible with a balanced ecosystem, there are numerous examples in history showing that several modern-day habitats originate from human activity: some of Latin America's rain forests owe their existence to humans planting and transplanting them, while the abundance of grazing animals in the Serengeti plain of A...	{ "page_id": 19468941, "title": "Balance of nature" }
to disappear entirely." At least in Midwestern America, the balance of nature idea was shown to be widely held by both science majors and the general student population. In a study at the University of Patras, educational sciences students were asked to reason about the future of ecosystems which suffered human-driven ...	{ "page_id": 19468941, "title": "Balance of nature" }
of nature through war; the 1997 film Princess Mononoke, depicts irresponsible activities by humans as having damaged the balance of nature; in the 2008 film Ponyo, the titular character disturbs the balance of nature when she seeks to become human. The titular character of the 2014 film Godzilla fights other sea monste...	{ "page_id": 19468941, "title": "Balance of nature" }
Distance measures are used in physical cosmology to give a natural notion of the distance between two objects or events in the universe. They are often used to tie some observable quantity (such as the luminosity of a distant quasar, the redshift of a distant galaxy, or the angular size of the acoustic peaks in the cos...	{ "page_id": 8065677, "title": "Distance measure" }
H {\displaystyle z\cdot d_{H}} for small z. According to the Friedmann equations, we also define a dimensionless Hubble parameter: E ( z ) = H ( z ) H 0 = Ω r ( 1 + z ) 4 + Ω m ( 1 + z ) 3 + Ω k ( 1 + z ) 2 + Ω Λ {\displaystyle E(z)={\frac {H(z)}{H_{0}}}={\sqrt {\Omega _{r}(1+z)^{4}+\Omega _{m}(1+z)^{3}+\Omega _{k}(1+z...	{ "page_id": 8065677, "title": "Distance measure" }
\| Ω k \| sin ⁡ ( \| Ω k \| d C ( z ) d H ) Ω k < 0 {\displaystyle d_{M}(z)={\begin{cases}{\frac {d_{H}}{\sqrt {\Omega _{k}}}}\sinh \left({\frac {{\sqrt {\Omega _{k}}}d_{C}(z)}{d_{H}}}\right)&\Omega _{k}>0\\d_{C}(z)&\Omega _{k}=0\\{\frac {d_{H}}{\sqrt {\|\Omega _{k}\|}}}\sin \left({\frac {{\sqrt {\|\Omega _{k}\|}}d_{C}(z)}{d_{...	{ "page_id": 8065677, "title": "Distance measure" }
1.0012 and increases it by the same factor for distant objects in the opposite direction. (The speed of the motion of the Earth around the Sun is only 30 km/s.) === Comoving distance === The comoving distance d C {\displaystyle d_{C}} between fundamental observers, i.e. observers that are both moving with the Hubble fl...	{ "page_id": 8065677, "title": "Distance measure" }
Ω r = Ω k = 0. {\displaystyle \Omega _{r}=\Omega _{k}=0.} In this case, we have: d C ( z ) = d H Ω m − 1 / 3 Ω Λ − 1 / 6 [ f ( ( 1 + z ) ( Ω m / Ω Λ ) 1 / 3 ) − f ( ( Ω m / Ω Λ ) 1 / 3 ) ] {\displaystyle d_{C}(z)=d_{H}\Omega _{m}^{-1/3}\Omega _{\Lambda }^{-1/6}[f((1+z)(\Omega _{m}/\Omega _{\Lambda })^{1/3})-f((\Omega _...	{ "page_id": 8065677, "title": "Distance measure" }
, where the transverse comoving distance d M {\displaystyle d_{M}} is defined appropriately. === Angular diameter distance === An object of size x {\displaystyle x} at redshift z {\displaystyle z} that appears to have angular size δ θ {\displaystyle \delta \theta } has the angular diameter distance of d A ( z ) = x / δ...	{ "page_id": 8065677, "title": "Distance measure" }
use the measured redshift, and another correction should be made for the peculiar velocity of the object by multiplying by ( 1 + v / c ) / ( 1 − v / c ) , {\textstyle {\sqrt {(1+v/c)/(1-v/c)}},} where now v is the component of the object's peculiar velocity away from us. In this way, the luminosity distance will be equ...	{ "page_id": 8065677, "title": "Distance measure" }

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