text stringlengths 2 4.67k | source dict |
|---|---|
Janet Patricia Gibson is a biologist and zoologist from Belize. She was awarded the Goldman Environmental Prize in 1990 for her efforts on conservation of the marine ecosystems along the Belizean coast, in particular the barrier reef system. The Belize Barrier Reef was granted UNESCO World Heritage status in 1996, thro... | {
"page_id": 22746194,
"title": "Janet Gibson"
} |
individual protection was insufficient as without a management approach that protected the entire barrier zone, external forces, like algae blooms spawned from fruit plantation waste, overfishing in other areas causing collateral damage, or sedimentation caused by development, were having detrimental impacts. Working w... | {
"page_id": 22746194,
"title": "Janet Gibson"
} |
Belize". Fisheries Research. 147. ElSevier Science Ltd.: 434–445. doi:10.1016/j.fishres.2013.03.011. Groosman, Britt; Gibson, Janet (14 March 2014). "European Union Fisheries Ban Ignores Belize Conservation Success Story". National Geographic. Archived from the original on October 26, 2014. Retrieved 6 September 2015. ... | {
"page_id": 22746194,
"title": "Janet Gibson"
} |
Specific appetite, also known as specific hunger, is a drive to eat foods with specific flavors or other characteristics. Regulation of homeostasis is essential to the survival of animals. Because the nutritional content of a diet will vary with environmental and other conditions, it is useful for animals to have a mec... | {
"page_id": 22025300,
"title": "Specific appetite"
} |
general, and methionine and lysine. Heat-stressed fowls seek out vitamin C, which alleviates the consequences of heat stress. Learned specific appetites are not necessarily a result of an animal's ability to detect the presence of a nutrient. Because nutrient deficiencies of various types can have stressful effects whi... | {
"page_id": 22025300,
"title": "Specific appetite"
} |
conclusions of this experiment have been contested. Nicotine implants in rats have been shown to induce a specific appetite for sucrose, even after removal of the implants. == Specific appetite in humans == There is very little strong evidence for specific appetite in humans. However, it has been demonstrated that huma... | {
"page_id": 22025300,
"title": "Specific appetite"
} |
In computational chemistry, distributed multipole analysis (DMA) is a compact and accurate way of describing the spatial distribution of electric charge within a molecule. == Multipole expansion == The DMA method was devised by Prof. Anthony Stone of Cambridge University to describe the charge distribution of a molecul... | {
"page_id": 11736149,
"title": "Distributed multipole analysis"
} |
distributed multipole site, re-expressing the series to account for the change of origin. The multipole expansion will no longer terminate, but the higher terms will be small. One may take the sites wherever one chooses, but they will usually be at the atoms. For small molecules one may wish to use additional sites at ... | {
"page_id": 11736149,
"title": "Distributed multipole analysis"
} |
methodologies for calculating intermolecular interaction energies, since it captures anisotropy of the atom-atom contributions to electrostatic interaction. It may therefore seem surprising that it has not been more widely used in molecular simulation. Possible reasons for this are: Its non-inclusion in popular simulat... | {
"page_id": 11736149,
"title": "Distributed multipole analysis"
} |
In statistics, the mean squared error (MSE) or mean squared deviation (MSD) of an estimator (of a procedure for estimating an unobserved quantity) measures the average of the squares of the errors—that is, the average squared difference between the estimated values and the true value. MSE is a risk function, correspond... | {
"page_id": 201816,
"title": "Mean squared error"
} |
The MSE either assesses the quality of a predictor (i.e., a function mapping arbitrary inputs to a sample of values of some random variable), or of an estimator (i.e., a mathematical function mapping a sample of data to an estimate of a parameter of the population from which the data is sampled). In the context of pred... | {
"page_id": 201816,
"title": "Mean squared error"
} |
} is a n × 1 {\displaystyle n\times 1} column vector. The MSE can also be computed on q data points that were not used in estimating the model, either because they were held back for this purpose, or because these data have been newly obtained. Within this process, known as cross-validation, the MSE is often called the... | {
"page_id": 201816,
"title": "Mean squared error"
} |
Bias ( θ ^ , θ ) 2 . {\displaystyle \operatorname {MSE} ({\hat {\theta }})=\operatorname {Var} _{\theta }({\hat {\theta }})+\operatorname {Bias} ({\hat {\theta }},\theta )^{2}.} ==== Proof of variance and bias relationship ==== MSE ( θ ^ ) = E θ [ ( θ ^ − θ ) 2 ] = E θ [ ( θ ^ − E θ [ θ ^ ] + E θ [ θ ^ ] − ... | {
"page_id": 201816,
"title": "Mean squared error"
} |
θ [ θ ^ ] − θ ) ( E θ [ θ ^ ] − E θ [ θ ^ ] ) + ( E θ [ θ ^ ] − θ ) 2 E θ [ θ ^ ] = constant = E θ [ ( θ ^ − E θ [ θ ^ ] ) 2 ] + ( E θ [ θ ^ ] − θ ) 2 = Var θ ( θ ^ ) + Bias θ ( θ ^ , θ ) 2 {\displaystyle {\begin{aligned}\operatorname {MSE} ({\hat {\theta }})&=\operatorname {E} _{\theta }\left[({\ha... | {
"page_id": 201816,
"title": "Mean squared error"
} |
using the well-known formula that for a random variable X {\textstyle X} , E ( X 2 ) = Var ( X ) + ( E ( X ) ) 2 {\textstyle \mathbb {E} (X^{2})=\operatorname {Var} (X)+(\mathbb {E} (X))^{2}} . By substituting X {\textstyle X} with, θ ^ − θ {\textstyle {\hat {\theta }}-\theta } , we have MSE ( θ ^ ) = E [ ( θ ^ − θ... | {
"page_id": 201816,
"title": "Mean squared error"
} |
related to known distribution of the data. The term mean squared error is sometimes used to refer to the unbiased estimate of error variance: the residual sum of squares divided by the number of degrees of freedom. This definition for a known, computed quantity differs from the above definition for the computed MSE of ... | {
"page_id": 201816,
"title": "Mean squared error"
} |
are still eligible for selection for all n {\displaystyle n} draws. The usual estimator for the population mean μ {\displaystyle \mu } is the sample average X ¯ = 1 n ∑ i = 1 n X i {\displaystyle {\overline {X}}={\frac {1}{n}}\sum _{i=1}^{n}X_{i}} which has an expected value equal to the true mean μ {\displaystyle \mu ... | {
"page_id": 201816,
"title": "Mean squared error"
} |
1 n ( γ 2 + 2 n n − 1 ) σ 4 , {\displaystyle \operatorname {MSE} (S_{n-1}^{2})={\frac {1}{n}}\left(\mu _{4}-{\frac {n-3}{n-1}}\sigma ^{4}\right)={\frac {1}{n}}\left(\gamma _{2}+{\frac {2n}{n-1}}\right)\sigma ^{4},} where μ 4 {\displaystyle \mu _{4}} is the fourth central moment of the distribution or population, and γ ... | {
"page_id": 201816,
"title": "Mean squared error"
} |
n + 1 n − 1 ) σ 4 − 2 ( n − 1 a ) σ 4 + σ 4 E [ S n − 1 4 ] = MSE ( S n − 1 2 ) + σ 4 = n − 1 n a 2 ( ( n − 1 ) γ 2 + n 2 + n ) σ 4 − 2 ( n − 1 a ) σ 4 + σ 4 {\displaystyle {\begin{aligned}\operatorname {MSE} (S_{a}^{2})&=\operatorname {E} \left[\left({\frac {n-1}{a}}S_{n-1}^{2}-\sigma ^{2}\right)^{2}\right]\\&=\op... | {
"page_id": 201816,
"title": "Mean squared error"
} |
the best unbiased estimator (minimum mean squared error among unbiased estimators) of variance for Gaussian distributions, if the distribution is not Gaussian, then even among unbiased estimators, the best unbiased estimator of the variance may not be S n − 1 2 . {\displaystyle S_{n-1}^{2}.} === Gaussian distribution =... | {
"page_id": 201816,
"title": "Mean squared error"
} |
given set of observations. == Applications == Minimizing MSE is a key criterion in selecting estimators; see minimum mean-square error. Among unbiased estimators, minimizing the MSE is equivalent to minimizing the variance, and the estimator that does this is the minimum variance unbiased estimator. However, a biased e... | {
"page_id": 201816,
"title": "Mean squared error"
} |
a loss function occurring naturally in an application. Like variance, mean squared error has the disadvantage of heavily weighting outliers. This is a result of the squaring of each term, which effectively weights large errors more heavily than small ones. This property, undesirable in many applications, has led resear... | {
"page_id": 201816,
"title": "Mean squared error"
} |
The Hubbard–Stratonovich (HS) transformation is an exact mathematical transformation invented by Russian physicist Ruslan L. Stratonovich and popularized by British physicist John Hubbard. It is used to convert a particle theory into its respective field theory by linearizing the density operator in the many-body inter... | {
"page_id": 8000600,
"title": "Hubbard–Stratonovich transformation"
} |
Amos de-Shalit (Hebrew: עמוס דה-שליט; September 29, 1926 – September 2, 1969) was an Israeli nuclear physicist and Israel Prize laureate. == Biography == Amos de-Shalit was born in Jerusalem in the British Mandate of Palestine (now Israel). He grew up in Tel Aviv and graduated from Gymnasia Balfour. In 1949, de-Shalit ... | {
"page_id": 31921243,
"title": "Amos de-Shalit"
} |
1965, he was awarded the Israel Prize in exact sciences, together with his colleague Professor Igal Talmi, for their work on "shell model" in nuclear physics. The De Shalit High School and two junior sister high schools in Rehovot were renamed after him. In 1974, In conjunction with the Weizmann Institute, the "Amos de... | {
"page_id": 31921243,
"title": "Amos de-Shalit"
} |
Organogenesis is the phase of embryonic development that starts at the end of gastrulation and continues until birth. During organogenesis, the three germ layers formed from gastrulation (the ectoderm, endoderm, and mesoderm) form the internal organs of the organism. The cells of each of the three germ layers undergo d... | {
"page_id": 1184860,
"title": "Organogenesis"
} |
form an enclosed tube which you can see in the development of vertebrates neural tube. Splits or pockets may form in the germinal sheet of cells forming vesicles or elongations. The lungs and glands of the organism may develop this way. A primary step in organogenesis for chordates is the development of the notochord, ... | {
"page_id": 1184860,
"title": "Organogenesis"
} |
Food physical chemistry is considered to be a branch of Food chemistry concerned with the study of both physical and chemical interactions in foods in terms of physical and chemical principles applied to food systems, as well as the applications of physical/chemical techniques and instrumentation for the study of foods... | {
"page_id": 32969820,
"title": "Food physical chemistry"
} |
in foods Disulfide bond breaking and formation in foods Food dispersions Structure-functionality in foods Food micro- and nano- structure Food gels and gelling mechanisms Cross-linking in foods Starch gelatinization and retrogradation Physico-chemical modification of carbohydrates Physico-chemical interactions in food ... | {
"page_id": 32969820,
"title": "Food physical chemistry"
} |
rheology Food extrusion Food packaging, food biotechnology Food safety Food science Food technology International Academy of Quantum Molecular Science List of important publications in chemistry § Physical chemistry List of unsolved problems in chemistry § Physical chemistry problems == References == == Journals == Jou... | {
"page_id": 32969820,
"title": "Food physical chemistry"
} |
In nuclear physics, the symmetry energy reflects the variation of the binding energy of the nucleons in the nuclear matter depending on its neutron to proton ratio as a function of baryon density. Symmetry energy is an important parameter in the equation of state describing the nuclear structure of heavy nuclei and neu... | {
"page_id": 62854237,
"title": "Symmetry energy"
} |
Sexual reproduction is a type of reproduction that involves a complex life cycle in which a gamete (haploid reproductive cells, such as a sperm or egg cell) with a single set of chromosomes combines with another gamete to produce a zygote that develops into an organism composed of cells with two sets of chromosomes (di... | {
"page_id": 21304415,
"title": "Sexual reproduction"
} |
Homologous chromosomes contain highly similar but not identical information, and by exchanging similar but not identical regions, genetic recombination increases genetic diversity among future generations. During sexual reproduction, two haploid gametes combine into one diploid cell known as a zygote in a process calle... | {
"page_id": 21304415,
"title": "Sexual reproduction"
} |
is from the Stenian period, about 1.05 billion years old. Biologists studying evolution propose several explanations for the development of sexual reproduction and its maintenance. These reasons include reducing the likelihood of the accumulation of deleterious mutations, increasing rate of adaptation to changing envir... | {
"page_id": 21304415,
"title": "Sexual reproduction"
} |
is with male peacocks fanning out their wings in order to show all their colors and attract a female mate. Lions with bigger and fuller manes are more likely to attract a female mate. Male deer with larger antlers are more likely to gain a female mate. These are just few of many examples in nature that show how sexual ... | {
"page_id": 21304415,
"title": "Sexual reproduction"
} |
females exchange sexual partners throughout their adult lives. === Fish === The vast majority of fish species lay eggs that are then fertilized by the male. Some species lay their eggs on a substrate like a rock or on plants, while others scatter their eggs and the eggs are fertilized as they drift or sink in the water... | {
"page_id": 21304415,
"title": "Sexual reproduction"
} |
are capable of asexual reproduction. All reproductive activity occurs through the cloaca, the single exit/entrance at the base of the tail where waste is also eliminated. Most reptiles have copulatory organs, which are usually retracted or inverted and stored inside the body. In turtles and crocodilians, the male has a... | {
"page_id": 21304415,
"title": "Sexual reproduction"
} |
plant form on land: 168, 173 and they reproduce either sexually or asexually. Often their most distinctive feature is their reproductive organs, commonly called flowers. The anther produces pollen grains which contain the male gametophytes that produce sperm nuclei. For pollination to occur, pollen grains must attach t... | {
"page_id": 21304415,
"title": "Sexual reproduction"
} |
side of the thallus, and swim in the film of water to the archegonia where they fertilize the egg. To promote out crossing or cross fertilization the sperm are released before the eggs are receptive of the sperm, making it more likely that the sperm will fertilize the eggs of different thallus. After fertilization, a z... | {
"page_id": 21304415,
"title": "Sexual reproduction"
} |
survive inclement times and to spread. There are typically three phases in the sexual reproduction of fungi: plasmogamy, karyogamy and meiosis. The cytoplasm of two parent cells fuse during plasmogamy and the nuclei fuse during karyogamy. New haploid gametes are formed during meiosis and develop into spores. The adapti... | {
"page_id": 21304415,
"title": "Sexual reproduction"
} |
of a plasmid into a host bacterial chromosome, and the subsequent transfer of a part of the host chromosome to another cell do not appear to be bacterial adaptations. Exposure of hyperthermophilic archaeal Sulfolobus species to DNA damaging conditions induces cellular aggregation accompanied by high frequency genetic m... | {
"page_id": 21304415,
"title": "Sexual reproduction"
} |
− Nature journal (2008) | {
"page_id": 21304415,
"title": "Sexual reproduction"
} |
Internally grooved copper tubes, also known as "microfin tubes", are a small diameter coil technology for modern air conditioning and refrigeration systems. Grooved coils facilitate more efficient heat transfer than smooth coils. Small diameter coils have better rates of heat transfer than conventionally-sized condense... | {
"page_id": 37753951,
"title": "Internally grooved copper tube"
} |
Optimizing transverse and longitudinal tube pitch by performance analysis and material cost. Optimizing fin pattern by comparing performances of fins with different patterns through computational fluid dynamics-based simulations. Testing the performance of heat exchangers with smaller diameter tubes. Developing empiric... | {
"page_id": 37753951,
"title": "Internally grooved copper tube"
} |
these new environmentally friendly refrigerants compared to those that are being phased out. Small diameter copper tubes are more desirable in applications with higher pressures. For tubes of the same thickness, smaller diameter tubes can withstand higher pressures than larger diameter tubes. Hence, as tube diameters d... | {
"page_id": 37753951,
"title": "Internally grooved copper tube"
} |
3/8 inch to 5 mm. The weights of the fin materials in the coils was 3.55 kg for the 9.52 mm coils, 2.61 kg for the 7 mm coils, and 1.55 kg for the 5 mm coils. == Antimicrobial == Copper is an antimicrobial material. Bio buildup can be reduced with copper coils. This helps to maintain high levels of energy efficiency fo... | {
"page_id": 37753951,
"title": "Internally grooved copper tube"
} |
Microgroove products expands the tubes circumferentially (i.e., the circumference of the tube is increased without changing the length). This "non-shrinkage" expansion allows for better control of tube lengths in preparation for subsequent assembly operations. Tubes are inserted, or laced, into the holes in a stack of ... | {
"page_id": 37753951,
"title": "Internally grooved copper tube"
} |
Duplornaviricota is a phylum of RNA viruses, which contains all double-stranded RNA viruses, except for those in phylum Pisuviricota. Characteristic of the group is a viral capsid composed of 60 homo- or heterodimers of capsid protein on a pseudo-T=2 lattice. Duplornaviruses infect both prokaryotes and eukaryotes. The ... | {
"page_id": 63771745,
"title": "Duplornaviricota"
} |
The molecular formula C20H26N2O2 (molar mass: 326.4 g/mol) may refer to: Ajmaline Dihydroquinidine Dihydroquinine Epsiprantel Tortuosamine Vincaminol | {
"page_id": 24384608,
"title": "C20H26N2O2"
} |
The DeLano Award for Computational Biosciences is a prize in the field of computational biology. It is awarded annually for "the most accessible and innovative development or application of computer technology to enhance research in the life sciences at the molecular level". The prize was established by the American So... | {
"page_id": 45159528,
"title": "DeLano Award for Computational Biosciences"
} |
The CAM clade is a clade containing the Archaeplastida (Plantae sensu lato) and the clade Pancryptista (which, in turn, contains Cryptista and Microheliella maris). This clade is supported by phylogenomic analyses from 2022 that mainly support the clade Pancryptista, but also mention that its closest lineage is Archaep... | {
"page_id": 77599850,
"title": "CAM (clade)"
} |
The molecular formula C7H8N2O2 may refer to: N1-Methyl-2-pyridone-5-carboxamide N1-Methyl-4-pyridone-3-carboxamide | {
"page_id": 60036202,
"title": "C7H8N2O2"
} |
God's Puzzle (神様のパズル, Kamisama no pazuru) is a Japanese science fiction film directed by Takashi Miike. The screenplay by Masa Nakamura is based on the novel God's Puzzle by Shinji Kimoto. == Plot == 17-year-old Saraka Homizu invents an infinity-shaped particle accelerator named Mugen. Meanwhile, sushi bar worker and a... | {
"page_id": 65737835,
"title": "God's Puzzle (film)"
} |
powerful typhoon over Tokyo, Saraka reverses the rotation of one of the rings of the Mugen accelerator and prepares a collision, feeding off of power from the national power grid that she has hacked. Airi, who was involved in posting the video of Saraka to the Internet, crashes his car through the East Side building, a... | {
"page_id": 65737835,
"title": "God's Puzzle (film)"
} |
a smart-kids-save-the-world actioner, adding Miike’s wacky narrative digressions and a bit of animation to mostly enjoyable effect." He complains that "Miike’s most conventional pic is least convincing in its serious moments, as would-be stimulating debates of God’s existence ring hollow" but writes that "pic’s cinemat... | {
"page_id": 65737835,
"title": "God's Puzzle (film)"
} |
Dynamic nuclear polarization (DNP) is one of several hyperpolarization methods developed to enhance the sensitivity of nuclear magnetic resonance (NMR) spectroscopy. While an essential analytical tool with applications in several fields, NMR’s low sensitivity poses major limitations to analyzing samples with low concen... | {
"page_id": 1119342,
"title": "Dynamic nuclear polarization"
} |
electron spins at a given magnetic field and temperature is described by the Boltzmann distribution under thermal equilibrium. A larger gyromagnetic moment corresponds to a larger Boltzmann distribution of populations in spin states; through DNP, the larger population distribution in the electronic spin reservoir is tr... | {
"page_id": 1119342,
"title": "Dynamic nuclear polarization"
} |
electron spin order such as chemical reactions (known as chemical-induced DNP or CIDNP), optical pumping, and spin injection. A polarizing agent (PA)—either an endogenous or exogenous paramagnetic system to the sample—is required as part of the DNP experimental setup. Typically, PAs are stable free radicals that are di... | {
"page_id": 1119342,
"title": "Dynamic nuclear polarization"
} |
and random interactions in this polarization transfer process. The DNP phenomenon was theoretically predicted by Albert Overhauser in 1953 and initially drew some criticism from Norman Ramsey, Felix Bloch, and other renowned physicists of the time on the grounds of being "thermodynamically improbable". The experimental... | {
"page_id": 1119342,
"title": "Dynamic nuclear polarization"
} |
by H = Δ ω e S z + ω n I z + A S z I z + B S z I x + ω 1 S x {\displaystyle H=\Delta \omega _{e}\;S_{z}+\omega _{\rm {n}}I_{z}+AS_{z}I_{z}+B\ S_{z}I_{x}+\omega _{1}S_{x}} where Δ ω e = ω e − ω M W {\displaystyle \Delta \omega _{e}=\omega _{e}-\omega _{\rm {MW}}} The MW irradiation can excite the electron single quantum... | {
"page_id": 1119342,
"title": "Dynamic nuclear polarization"
} |
frequency shifts up or down by the nuclear Larmor frequency from the electron Larmor frequency in the discussed two-spin system. The direction of frequency shifts corresponds to the sign of DNP enhancements. Solid effect exist in most cases but is more easily observed if the linewidth of the EPR spectrum of involved un... | {
"page_id": 1119342,
"title": "Dynamic nuclear polarization"
} |
only occur if the inhomogeneously broadened EPR lineshape has a linewidth broader than the nuclear Larmor frequency. Therefore, as this linewidth is proportional to external magnetic field B0, the overall DNP efficiency (or the enhancement of nuclear polarization) scales as B0−1. This remains true as long as the relaxa... | {
"page_id": 1119342,
"title": "Dynamic nuclear polarization"
} |
inter-electron interactions. The strong interactions lead to a homogeneously broadened EPR lineshape of the involved paramagnetic species. The linewidth is optimized for polarization transfer from electrons to nuclei, when it is close to the nuclear Larmor frequency. The optimization is related to an embedded three-spi... | {
"page_id": 1119342,
"title": "Dynamic nuclear polarization"
} |
interactions. These electrons give rise to an Overhauser enhancement centered at a microwave offset of ωe − ωH = 0. The cellulose char also exhibits electrons undergoing thermal mixing effects (TM). While the enhancement curve reveals the types electron-nuclear spin interactions in a material, it is not quantitative an... | {
"page_id": 1119342,
"title": "Dynamic nuclear polarization"
} |
23597038. Sze, Kong Hung; Wu, Qinglin; Tse, Ho Sum; Zhu, Guang (2011). "Dynamic Nuclear Polarization: New Methodology and Applications". NMR of Proteins and Small Biomolecules. Topics in Current Chemistry. Vol. 326. pp. 215–42. doi:10.1007/128_2011_297. ISBN 978-3-642-28916-3. PMID 22057860. Miéville, Pascal; Jannin, S... | {
"page_id": 1119342,
"title": "Dynamic nuclear polarization"
} |
polarization of nuclei in solid dielectrics". Soviet Physics Uspekhi. 21 (9): 725–745. Bibcode:1978SvPhU..21..725A. doi:10.1070/PU1978v021n09ABEH005678. Wind, R.A.; Duijvestijn, M.J.; Van Der Lugt, C.; Manenschijn, A.; Vriend, J. (1985). "Applications of dynamic nuclear polarization in 13C NMR in solids". Progress in N... | {
"page_id": 1119342,
"title": "Dynamic nuclear polarization"
} |
On the Shoulders of Giants: The Great Works of Physics and Astronomy is a compilation of scientific texts edited and with commentary by the British theoretical physicist Stephen Hawking. The book was published by Running Press in 2002. == Content == The book includes selections from the following works in English: On t... | {
"page_id": 36574320,
"title": "On the Shoulders of Giants (book)"
} |
Microbial toxins are toxins produced by micro-organisms, including bacteria, fungi, protozoa, dinoflagellates, and viruses. Many microbial toxins promote infection and disease by directly damaging host tissues and by disabling the immune system. Endotoxins most commonly refer to the lipopolysaccharide (LPS) or lipoolig... | {
"page_id": 21107825,
"title": "Microbial toxin"
} |
of Gram-negative bacteria. Not all strains of a bacteria species are virulent; there are some strains of Corynebacterium diphtheriae that do not produce diphtheria toxin and are considered nonvirulent and nontoxigenic. Additional classifications used to describe toxins include enterotoxin, neurotoxin, leukocidin or hem... | {
"page_id": 21107825,
"title": "Microbial toxin"
} |
the host's cell. The mechanism that clostridial toxins follow includes clostridia forming pores and then the pores inserting themselves into the cell membrane of cells. Clostridial toxins have the ability to damage or alter the cell membrane damaging the extracellular matrix of the organism. Toxin A and toxin B are two... | {
"page_id": 21107825,
"title": "Microbial toxin"
} |
in cell communication throughout the body. When tetanus toxin enters the body it is taken up by cholinergic nerve endings traveling axonally into the brain and spinal cord, disrupting motor function in individuals. Although tetanus is a damaging toxin that has a multitude of symptoms it can be prevented through vaccina... | {
"page_id": 21107825,
"title": "Microbial toxin"
} |
is produced by STEC and not S. dysenteriae. Stx2 is produced only by STEC and is antigenically different from Stx/Stx1. The term shiga-like toxins was previously used to further distinguish the shiga toxins produced by E. coli, but nowadays, they are collectively referred to as shiga toxins. Within the STEC strains, a ... | {
"page_id": 21107825,
"title": "Microbial toxin"
} |
of the neck, and difficulty breathing. Diphtheria toxin is an ADP-ribosyltransferase that inhibits protein synthesis which causes the symptoms associated with the disease. Diphtheria used to be a leading cause of childhood death until the creation of a vaccine. The diphtheria vaccine contains a diphtheria toxoid, antig... | {
"page_id": 21107825,
"title": "Microbial toxin"
} |
of the immune system's destruction of the bacteria cell membrane. ==== BMAA ==== β-Methylamino-L-alanine (BMAA) is a neurotoxin produced by cyanobacteria that live in the roots of cycads. BMAA may be present in starch made from the stems and/or seeds of cycads (such as Florida arrowroot flour) that has not been suffici... | {
"page_id": 21107825,
"title": "Microbial toxin"
} |
toxins generated by microalgae or cyanobacteria, known as cyanotoxins. The adsorption is passive, and the biotoxins adhere to porous, resin filled sachets, or SPATT bags where they are then physically removed and examined. SPATT is a useful tool in tracking algal blooms as it is reliable, sensitive, and inexpensive. It... | {
"page_id": 21107825,
"title": "Microbial toxin"
} |
that looks at nucleic acid quantifications. Digital PCR uses dilutions and samples from microlitre reactions to achieve a more accurate quantification of nucleic acids. This type offers a more linear analysis by looking at the positive and negative reactions. Both PCR's are beneficial but there are advantages and disad... | {
"page_id": 21107825,
"title": "Microbial toxin"
} |
being tested in laboratories are uses of nanowires and other nanomaterials to detect microbial toxins. == Tetrodotoxins == These toxins are produced by Vibrio species of bacteria and like to accumulate in marine life such as the pufferfish. These toxins are produced when Vibrio bacteria are stressed by changes in tempe... | {
"page_id": 21107825,
"title": "Microbial toxin"
} |
in infant mice in an age-dependent manner. NSP4 can induce aqueous secretion in the gastrointestinal tract of neonatal mice through activation of an age- and Ca2+-dependent plasma membrane anion permeability. === Virus involvement in toxigenicity === Several bacteriophages contain toxin genes that become incorporated i... | {
"page_id": 21107825,
"title": "Microbial toxin"
} |
of the Saccharomyces cerevisiae species, that destroy neighboring yeast cells. Recently, researchers discovered that it is only the yeasts infected with either ScV-M1, ScV-M2, or ScV-M28 mycoviruses that have the ability to produce a "killer toxin". == Mycotoxins == Mycotoxins are secondary metabolites that are constru... | {
"page_id": 21107825,
"title": "Microbial toxin"
} |
in cereal, spices, and seeds. They can also be found in eggs, milk, and meat from animals that have been contaminated during their feeding process. Since they are resistant to high temperatures and physical and chemical reception, it is considered unavoidable while cooking at high temperatures. === Types === Trichothec... | {
"page_id": 21107825,
"title": "Microbial toxin"
} |
fumonisins are birth defects of the brain, spine, and spinal cord. In animals, problems with the pulmonary edema and hydrothorax swines have been proven to have association with fumonisins. Ochratoxin is a mycotoxin that is produced by Aspergillus species and Penicillium species. The most researched ochratoxin is the o... | {
"page_id": 21107825,
"title": "Microbial toxin"
} |
A photolabile protecting group (PPG; also known as: photoremovable, photosensitive, or photocleavable protecting group) is a chemical modification to a molecule that can be removed with light. PPGs enable high degrees of chemoselectivity as they allow researchers to control spatial, temporal and concentration variables... | {
"page_id": 53089397,
"title": "Photolabile protecting group"
} |
photochemical process The chromophore should absorb incident light with reasonable absorptivity The excitation wavelength of light should be greater than 300 nm The media and photoproducts should not absorb the incident light A general, high-yield synthetic procedure should exist for attaching the PPG to an unprotected... | {
"page_id": 53089397,
"title": "Photolabile protecting group"
} |
quantum yields of nitrobenzyl-based PPGs, several beneficial modifications have been identified. The largest increase in quantum yield and reaction rate can be achieved through substitution at the benzylic carbon. However, potential substitutions must leave one hydrogen atom so the photodegradation can proceeded uninhi... | {
"page_id": 53089397,
"title": "Photolabile protecting group"
} |
carboxylates and carbamates. As with nitrobenzyl-based PPGs, several modifications are known. For example, the 3',5'-dimethoxybenzoin PPG (DMB) contains a 3,5-dimethoxyphenyl substituent on the carbonyl's α-carbon. Under certain conditions, DMB has exhibited quantum yields as high as 0.64. Additionally, the p-hydroxyph... | {
"page_id": 53089397,
"title": "Photolabile protecting group"
} |
these PPGs react through abstraction of the carbonyl's γ-hydrogen. The compound is then able to undergo a photoenolization, which is mechanistically like a keto-enol tautomerization. From the enol form, the compound can finally undergo a ground-state transformation that releases the substrate. The quantum yield of this... | {
"page_id": 53089397,
"title": "Photolabile protecting group"
} |
with a PPG is commonly referred to as "photocaging." This term is especially popular in biological systems. For example, Ly et al. developed a p-iodobenzoate-based photocaged reagent, which would experience a homolytic photoclevage of the C-I bond. They found that the reaction could occur with excellent yields, and wit... | {
"page_id": 53089397,
"title": "Photolabile protecting group"
} |
stranded polynucleotides were generated in a step-wise “grafting from” method. In separate studies, there have been multiple reports of using PPGs to enable the selective separation of blocks within block-copolymers to expose fresh surfaces. Furthermore, this surface patterning method has since been extended to protein... | {
"page_id": 53089397,
"title": "Photolabile protecting group"
} |
Ministeria vibrans is a bacterivorous amoeba with filopodia that lives suspended by a flagellum-derived stalk attached to the substrate. The life cycle of Ministeria remains unknown. == Taxonomy == Two Ministeria species have been reported so far, both of them from coastal marine water samples: M. vibrans and M. mariso... | {
"page_id": 21959798,
"title": "Ministeria vibrans"
} |
The Brazilian Archives of Biology and Technology is a continuous peer-reviewed scientific journal covering all areas of fundamental and applied biology. It was established in 1946 as the Arquivos de Biologia e Tecnologia, publishing in Portuguese. It obtained its current name in 1998, when it switched to publication in... | {
"page_id": 49288310,
"title": "Brazilian Archives of Biology and Technology"
} |
Ghabrivirales is an order of double-stranded RNA viruses. It is the only order in the class Chrysmotiviricetes. The name of the class is a portmanteau of member families: chrysoviridae, megabirnaviridae, and totiviridae; and -viricetes which is the suffix for a virus class. The name of the order derives from Said Ghabr... | {
"page_id": 63771768,
"title": "Ghabrivirales"
} |
In chemistry, coprecipitation (CPT) or co-precipitation is the carrying down by a precipitate of substances normally soluble under the conditions employed. Analogously, in medicine, coprecipitation (referred to as immunoprecipitation) is specifically "an assay designed to purify a single antigen from a complex mixture ... | {
"page_id": 11146362,
"title": "Coprecipitation"
} |
or strongly, bound (adsorbed) to the surface of the precipitate. An occlusion occurs when an adsorbed impurity gets physically trapped inside the crystal as it grows. Besides its applications in chemical analysis and in radiochemistry, coprecipitation is also important to many environmental issues related to water reso... | {
"page_id": 11146362,
"title": "Coprecipitation"
} |
are said to be homogeneous). This is the case when diffusion in the interior is possible (like in the liquids) or when the initial small crystals are allowed to recrystallize. Kinetic effects (like speed of crystallization and presence of mixing) play a role. == See also == Fajans–Paneth–Hahn Law == References == | {
"page_id": 11146362,
"title": "Coprecipitation"
} |
In pure and applied mathematics, quantum mechanics and computer graphics, a tensor operator generalizes the notion of operators which are scalars and vectors. A special class of these are spherical tensor operators which apply the notion of the spherical basis and spherical harmonics. The spherical basis closely relate... | {
"page_id": 39654522,
"title": "Tensor operator"
} |
z ^ {\displaystyle p{\mathbf {\hat {z}} }} and p x ^ {\displaystyle p{\mathbf {\hat {x}} }} . The kinetic energy on the other hand must be represented by a scalar operator, whose expected value must be the same in the initial and the rotated states. In the same way, tensor quantities must be represented by tensor opera... | {
"page_id": 39654522,
"title": "Tensor operator"
} |
and j {\displaystyle j} can independently take on the values 1, 2, and 3 (or x {\displaystyle x} , y {\displaystyle y} , and z {\displaystyle z} ) corresponding to the three Cartesian axes, the index α {\displaystyle \alpha } runs over all particles (electrons and nuclei) in the molecule, q α {\displaystyle q_{\alpha }... | {
"page_id": 39654522,
"title": "Tensor operator"
} |
}})} be a rotation matrix. According to the Rodrigues' rotation formula, the rotation operator then amounts to U [ R ( θ , n ^ ) ] = 1 1 − i sin θ ℏ n ^ ⋅ J − 1 − cos θ ℏ 2 ( n ^ ⋅ J ) 2 . {\displaystyle U[R(\theta ,{\hat {\mathbf {n} }})]=1\!\!1-{\frac {i\sin \theta }{\hbar }}{\hat {\mathbf {n} }}\cdot \mathbf {J}... | {
"page_id": 39654522,
"title": "Tensor operator"
} |
c j m U ( R ) | j , m ⟩ {\displaystyle |{\bar {\psi }}\rangle =U(R)|\psi \rangle =\sum _{m}c_{jm}U(R)|j,m\rangle } Using the completeness condition: I = ∑ m ′ | j , m ′ ⟩ ⟨ j , m ′ | {\displaystyle I=\sum _{m'}|j,m'\rangle \langle j,m'|} we have | ψ ¯ ⟩ = I U ( R ) | ψ ⟩ = ∑ m m ′ c j m | j , m ′ ⟩ ⟨ j , m ′ | U ( R ) ... | {
"page_id": 39654522,
"title": "Tensor operator"
} |
! ( ℓ + m ) ! P ℓ m ( cos θ ) e i m ϕ {\displaystyle Y_{\ell }^{m}(\theta ,\phi )=\langle \theta ,\phi |\ell ,m\rangle ={\sqrt {{(2\ell +1) \over 4\pi }{(\ell -m)! \over (\ell +m)!}}}\,P_{\ell }^{m}(\cos {\theta })\,e^{im\phi }} where Pℓm is an associated Legendre polynomial, ℓ is the orbital angular momentum quantum... | {
"page_id": 39654522,
"title": "Tensor operator"
} |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.