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Piezo1 has been shown to sense RNA in the gut and relay this information through serotonin synthesis to the bone by acting as a sensor of single-stranded RNA (ssRNA) governing 5-HT production. Intestinal epithelium-specific deletion of mouse Piezo1 profoundly disturbed gut peristalsis, impeded experimental colitis, and suppressed serum 5-HT levels. Because of systemic 5-HT deficiency, conditional knockout of Piezo1 increased bone formation. | https://en.wikipedia.org/wiki/Serotonin |
Notably, fecal ssRNA was identified as a natural Piezo1 ligand, and ssRNA-stimulated 5-HT synthesis from the gut was evoked in a MyD88/TRIF-independent manner. Colonic infusion of RNase A suppressed gut motility and increased bone mass. These findings suggest gut ssRNA as a master determinant of systemic 5-HT levels, indicating the ssRNA-Piezo1 axis as a potential prophylactic target for treatment of bone and gut disorders. Studies in 2008, 2010 and 2019 have opened the potential for serotonin research to treat bone mass disorders. | https://en.wikipedia.org/wiki/Serotonin |
In mice it seems to be an immune factor regulating T-cell checkpoints, and it could be a target for future checkpoint inhibitor anti-cancer drugs.PSGL-1 has been shown to bind to VISTA (V-domain Ig suppressor of T cell activation) but this binding only occurs under acidic pH conditions (pH < 6.5) such as can be found in tumor microenvironments (TME). In mice, PSGL-1 seems to facilitate T cell exhaustion in tumors. | https://en.wikipedia.org/wiki/P-selectin_glycoprotein_ligand-1 |
In mice models, mutations in the Nbs1 subunit of MRN alone (producing the phenotypic analog of Nijmegen Breakage Syndrome in humans) have failed to produce tumorigenesis. However, double knockout mice with mutated Nbs1 which were also null of the p53 tumor suppressor gene displayed tumor onset significantly earlier than their p53 wildtype controls. This implies that Nbs1 mutations are themselves sufficient for tumorigenesis; a lack of malignancy in the control seems attributable to the activity of p53, not of the benignity of Nbs1 mutations. Extension studies have confirmed an increase in B and T-cell lymphomas in Nbs1-mutated mice in conjunction with p53 suppression, indicating potential p53 inactivation in lymphomagenesis, which occurs more often in NBS patients. | https://en.wikipedia.org/wiki/MRN_complex |
Knockdown of MRE11 in various human cancer cell lines has also been associated with a 3-fold increase in the level of p16INK4a tumor suppressor protein, which is capable of inducing cellular senescence and subsequently halting tumor cell proliferation. This is thought primarily to be the result of methylation of the p16INK4 promotor gene by MRE11. These data suggest maintaining the integrity and normal expression levels of MRN provides a protective effect against tumorigenesis. | https://en.wikipedia.org/wiki/MRN_complex |
In mice the intraperitoneal LD50 of HWTX-I is 0.70 mg/kg, the intracisternal LD50 has been determined as 9.40 µg/kg. Neurotoxic symptoms after intraperitoneal injection were gasping, excitation, spastic paralysis of the hindlimb and asynergia.HWTX-I is a potential novel analgesic pharmaceutic. Epidural administration of HWTX-I in rats with chronic neuropathic pain blocked heat hyperalgesia and mechanical allodynia in the injured hindpaw of rats, indicating that epidurally administered HWTX-I could alleviate neuropathic pain. Cytosolic Ca2+ overload is one of the primary factors for inflammatory cells activation, therefore Ca2+ channel blockers can have a potential role as an anti-inflammatory drug. HWTX-I can relieve pain in the inflammatory joints and eliminate arthrocele to some degree. In a rat model of rheumatoid arthritis HWTX-I is able to decrease the concentration of tumor necrosis factor α (TNF-α) in serum and decrease the mRNA expression level interleukin 1β (IL-1β) and interleukin 6 (IL-6). | https://en.wikipedia.org/wiki/Huwentoxin |
In mice where the Doublecortin gene has been knocked out, cortical layers are still correctly formed. However, the hippocampi of these mice show disorganisation in the CA3 region. The normally single layer of pyramidal cells in mutants is seen as a double layer. These mice also have different behavior than their wild type littermates and are epileptic. | https://en.wikipedia.org/wiki/Doublecortin |
In mice, EP4 receptor agonists reduce the acute rejection of transplanted hearts, prolong the survival of heart-transplanted animals, and reduce cardiac damage in a model of ischemic reperfusion injury but also stimulate cardiac hypertrophy accompanied by poor cardiac function. EP4 receptor-depleted mice exhibit more severe cardiac damage in experimental models of myocardial infarction and ischemic reperfusion injury but also develop cardiac hypertrophy with poor cardiac function. Cardiac specific EP4 deficiency using Site-specific recombination by the Cre recombinase method to inactivate EP4 only in cardiac muscle causes a somewhat different form of cardiac disease, dilated cardiomyopathy, that develops within 23–33 weeks after birth in mice. These studies are interpreted as indicating that EP4 plays both protective and damaging roles in the heart with the protective effects of EP4 due at least in part to its ability to suppress inflammation. | https://en.wikipedia.org/wiki/EP4_receptor |
In mice, Lim-1 acts in the early development of the mesoderm and ectoderm layers of the developing embryo. The factor is induced by the increasing concentrations of Cerberus, DKK1, and Nodal around day 7–9 in the mouse embryo. Lim-1 contributes to the formation of the anterior portion of the developing head containing the forebrain and midbrain. Research studies have shown that knocking out Lim-1 in mice will cause a range of head deformities, including the complete lack of formation of the head. | https://en.wikipedia.org/wiki/Transcription_factor_Lim-1 |
In mice, PGCs are specified in the proximal epiblast and subsequently migrate through the primitive streak towards the endoderm. The PGCs then embed themselves within the epithelium of the hind-gut and from there will migrate towards the mesoderm via the dorsal mesentery. There is then bilateral migration of the PGCs to the developing gonadal ridges which follows a pattern very similar to that found in Drosophila. | https://en.wikipedia.org/wiki/Primordial_germ_cell_migration |
In mice, Ts8 increases earlier nociception with higher doses. Elimination or inhibition of Kv4.2 channels via intraplantar injections was seen to induce hypersensitivity to mechanical stimuli. Via intrathecal injection this effect was prolonged and a prolongation plateau of mechanical hypersensitivity was observed. Thus Ts8 can enhance sensitivity to tactile- and mechanical stimuli in mice, by inhibition of the Kv4.2 channels. The symptoms caused by Ts8 induce hyperalgesia, intense and persistent pain.Ts8 is toxic to human erythrocytes type A+ in concentrations above 2.89 µM. | https://en.wikipedia.org/wiki/Ts8 |
In mice, a one-year study of 50 males and 50 females was performed. The mice received diets containing methiocarb at doses of 0, 15, 43 and 130 mg/kg bw per day in males and 0, 20, 57, and 170 mg/kg bw per day in females. Food consumption, behaviour and mortality rate were not affected at any dose. At one month the decrease in plasma acetylcholinesterase activity was the highest and the smallest reductions were observed at 24 months. | https://en.wikipedia.org/wiki/Methiocarb |
Brain acetylcholinesterase activity was also lowered, more in males than in females. In rats a two-year study of 60 rats was performed. | https://en.wikipedia.org/wiki/Methiocarb |
The rats received diets containing 0, 3.3, 9.3 and 29 mg/kg bw per day for males and 0, 5, 14, and 42 mg/kg bw per day for females. Food consumption, behaviour and mortality rate were not affected at any dose. The total protein concentrations were raised at higher doses of methiocarb. The plasma acetylcholinesterase activity was lowered at the high dose at day one and from eight weeks onwards in males and at day one and 1, 2, 4 and 13 weeks in females. No brain acetylcholinesterase activity was observed. | https://en.wikipedia.org/wiki/Methiocarb |
In mice, both males and females choose MHC-dissimilar partners. Mice develop the ability to identify family members during early growth and are known to avoid inbreeding with kin, which would support the MHC-mediated mate choice hypothesis for inbreeding avoidance.Fish are another group of vertebrates shown to display MHC-associated mate choice. Scientists tested the Atlantic salmon, Salmo salar, by observing effects of MHC upon natural spawning salmon that resided in the river versus artificial crosses that were carried out in hatcheries. Logically, the artificial crosses would be bereft of the benefits of mate choice that would naturally be available. | https://en.wikipedia.org/wiki/Major_Histocompatibility_Complex_and_Sexual_Selection |
The results showed that the offspring of the artificially bred salmon were more infected with parasites: almost four times more than the naturally-spawned offspring were. In addition, wild offspring were more MHC-heterozygous than the artificially-bred offspring. These results support the Heterozygous Advantage hypothesis of sexual selection for MHC-dissimilar mate choice. | https://en.wikipedia.org/wiki/Major_Histocompatibility_Complex_and_Sexual_Selection |
In another fish, the three-spined stickleback, it has been shown that females desire MHC diversity in their offspring, which affects their mate choice.Female Savannah sparrows, Passerculus sandwichensis, chose MHC-dissimilar males to mate with. Females are more likely to engage in extra-pair relationships if paired with MHC-similar mates and more dissimilar mates are available. Similarly, MHC diversity in house sparrows, Passer domesticus, suggests that MHC-disassortative mate choice occurs.MHC-mediated mate choice has been shown to exist in Swedish sand lizards, Lacerta agilis. | https://en.wikipedia.org/wiki/Major_Histocompatibility_Complex_and_Sexual_Selection |
Females preferred to associate with odor samples obtained from males more distantly related at the MHC I loci.Even though many species are socially monogamous, females can accept or actively seek mating outside of the relationship; extra-pair paternity is a mating pattern known to be affiliated with MHC-associated mate choice. Birds are one of the more commonly studied groups of animals to exhibit this sexual behavior. In the scarlet rosefinch Carpocus erythrinus, females engaged in extra-pair paternity much less frequently when their mates were MHC-heterozygous. | https://en.wikipedia.org/wiki/Major_Histocompatibility_Complex_and_Sexual_Selection |
In the Seychelles warbler Acrocephalus sechellensis, there was no evidence of MHC variation between social mates. However, when females' social mates were MHC-similar, they were more likely to participate in extra-pair paternity; in most cases, the extra-pair male was significantly more MHC-dissimilar than the social mate.MHC-mediated mate choice may occur after copulation, at the gametic level, through sperm competition or female cryptic choice. The Atlantic salmon, Salmo salar, is one species in which sperm competition is influenced by the variation in the major histocompatibility complex, specifically that of the Class I alleles. | https://en.wikipedia.org/wiki/Major_Histocompatibility_Complex_and_Sexual_Selection |
Atlantic salmon males have higher rates of successful fertilization when competing for eggs from females genetically similar at the class I genes of the MHC.Another species that exhibits MHC-associated cryptic choice is the Arctic charr Salvelinus alpinus. In this case, however, it seems that sperm selection is more dependent on the ovum. MHC-heterozygous males were found to have significantly more fertilization success than MHC-homozygous males; sperm count, motility, and swimming velocity were not shown to significantly co-vary with similarity or dissimilarity at the MHC. | https://en.wikipedia.org/wiki/Major_Histocompatibility_Complex_and_Sexual_Selection |
It is proposed that there is a chemo-attraction system responsible for the egg itself being able to discriminate and selectively choose between MHC-heterozygous and MHC-homozygous males.Contrary to the Atlantic salmon and the Arctic char, red junglefowl Gallus gallus males instead of females exert cryptic preference. Male junglefowl showed no preference when simultaneously presented with both an MHC-dissimilar and an MHC-similar female. However, they did show a cryptic preference by allocating more sperm to the more MHC-dissimilar of the two.Male sand lizards Lacerta agilis behave similarly to the male junglefowl. | https://en.wikipedia.org/wiki/Major_Histocompatibility_Complex_and_Sexual_Selection |
Initial copulation between a male and a female without any rivals was shown to be extended when the male sensed a higher female fecundity. However, second males adjusted the duration of their copulation depending on the relatedness between the female and the first male, believed to be determined by the MHC-odor of the copulatory plug. A closer genetic relatedness between a male and a female sand lizard increased the chances for a successful fertilization and rate of paternity for the second male.Abortional selection may be a form of cryptic female choice. Many studies on humans and rodents have found that females may spontaneously abort pregnancies in which the offspring is too MHC-similar. In addition, in vitro fertilizations are more likely to fail when couples have similar MHC genes. | https://en.wikipedia.org/wiki/Major_Histocompatibility_Complex_and_Sexual_Selection |
In mice, complete inactivation of the FXN homolog (Frda) is lethal in the early embryonic stage. Although nearly all organisms express a frataxin homologue, the GAA repeat in intron 1 only exists in humans and other primates, so the mutation that causes FDRA can't occur naturally in other animals. Scientists have developed several options to model this disease in mice. One approach is to silence frataxin expression in just one specific tissue type of interest: the heart (mice modified this way are called MCK), all neurons (NSE), or just the spinal cord and cerebellum (PRP). | https://en.wikipedia.org/wiki/Frataxin |
Another approach involves inserting a GAA expansion into the first intron of the mouse FXN gene, which should inhibit frataxin production, just like in humans. Mice that are homozygous for this modified gene are called KIKI (knock-in knock-in), and the compound heterozygotes formed by crossing KIKI mice with frataxin knockout mice are called KIKO (knock-in knock-out). However, even KIKO mice still express 25-36% of the normal frataxin level, and show very mild symptoms. | https://en.wikipedia.org/wiki/Frataxin |
The final approach involves creating transgenic mice with a GAA-expanded version of the human frataxin gene. These mice are called YG22R (one GAA sequence of 190 repeats) and YG22R (two GAA sequences of 90 and 190 repeats). These mice show symptoms similar to human patients.An overexpression of frataxin in Drosophila has shown an increase in antioxidant capability, resistance to oxidative stress insults and longevity, supporting the theory that the role of frataxin is to protect the mitochondria from oxidative stress and the ensuing cellular damage. | https://en.wikipedia.org/wiki/Frataxin |
Fibroblasts from a mouse model of FRDA and FRDA patient fibroblasts show increased levels of DNA double-strand breaks. A lentivirus gene delivery system was used to deliver the frataxin gene to the FRDA mouse model and human patient cells, and this resulted in long-term restored expression of frataxin mRNA and frataxin protein. This restored expression of the frataxin gene was accompanied by a substantial reduction in the number of DNA double-strand breaks. The impaired frataxin in FRDA cells appears to cause reduced capacity for repair of DNA damage and this may contribute to neurodegeneration. | https://en.wikipedia.org/wiki/Frataxin |
In mice, during gastrulation on embryological day 7.5, cells fated to become intermediate mesoderm show the mouse OSR1 homologue, Osr1, expression. A day later, it is expressed in the intermediate mesoderm, lateral to the neural plate. Osr1 expression weakens and shifts posteriorly, to the presumptive kidneys, by day 9.5. By day 10.5, the branchial arch and limbs also begin to express Osr1. | https://en.wikipedia.org/wiki/OSR1 |
In mice, haploinsufficiency of the Dgcr8 gene has been linked to improper regulation of the microRNA miR-338 and 22q11.2 deletion phenotypes. | https://en.wikipedia.org/wiki/DiGeorge_Syndrome |
In mice, it has been estimated that dendritic cells are replenished from the blood at a rate of 4000 cells per hour, and undergo a limited number of divisions during their residence in the spleen over 10 to 14 days. | https://en.wikipedia.org/wiki/Dendritic_cells |
In mice, knockout of Mixl1 has resulted in embryonic death at E.8.5 due abnormalities in axial morphogenesis and a disruption of definitive endoderm. Overexpression of Mixl1 resulted in impaired hematopoietic differentiation which results in acute myeloid leukemia. In humans Mixl1 has been detected in leukemic cells lines from biopsy samples of individuals with high-grade lymphoma.Observed Mixl1-null mutants resulted in embryonic arrest at the early somite stage. These mutants had a thick primitive streak, abnormal head folds, absence of heart tube and gut, and enlarged midline tissue mass that replaced the notochord. | https://en.wikipedia.org/wiki/MIXL1 |
In mice, knockout studies of Mef2c have demonstrated that crucial role that it plays in heart development. Mice without the Mef2c die during embryonic day 9.5–10 with major heart defects, including improper looping, outflow tract abnormalities, and complete lack of the right ventricle. This indicates improper differentiation of the anterior heart field. When Mef2c is knocked out specifically in the AHF, the mice die at birth with a range of outflow tract defects and severe cyanosis. Thus, Mef2 is necessary for many aspects of heart development, specifically by regulating the anterior heart field. | https://en.wikipedia.org/wiki/Mef2 |
In mice, monocytes can be divided in two subpopulations. Inflammatory monocytes (CX3CR1low, CCR2pos, Ly6Chigh, PD-L1neg), which are equivalent to human classical CD14++ CD16− monocytes and resident monocytes (CX3CR1high, CCR2neg, Ly6Clow, PD-L1pos), which are equivalent to human non-classical CD14+ CD16+ monocytes. Resident monocytes have the ability to patrol along the endothelium wall in the steady state and under inflammatory conditions. | https://en.wikipedia.org/wiki/Monocyte |
In mice, mutation of SMAD3 has been linked to colorectal adenocarcinoma, increased systemic inflammation, and accelerated wound healing. Studies have shown that mutations in SMAD3 gene promote colorectal cancer in mice. The altered activity of SMAD3 was linked to chronic inflammation and somatic mutations that contribute to chronic colitis and the development of colorectal cancer. The results generated on mice helped identify SMAD3 like a possible player in human colorectal cancer. The impact of SMAD3 has also been analyzed in colorectal cancer human cell lines, using single-nucleotide polymorphism (SNP) microarray analysis. The results showed reductions in SMAD3 transcriptional activity and SMAD2-SMAD4 complex formation, underlining the critical roles of these three proteins within the TGF-β signaling pathway and the impact of this pathway in colorectal cancer development. | https://en.wikipedia.org/wiki/Mothers_against_decapentaplegic_homolog_3 |
In mice, prenatal testosterone transfer causes higher blood concentrations of testosterone in 2M females when compared to 1M or 0M females. This has a variety of consequences on later female behavior, physiology, and morphology. Below is a table comparing physiological, morphological, and behavioral differences of 0M and 2M female mice. | https://en.wikipedia.org/wiki/Prenatal_testosterone_transfer |
In mice, the BMP-15 homologue is not as physiologically important. Upon targeted deletion of a bmp15 exon, the mice presented with only subfertility in homozygotes and no clear aberrant phenotype in heterozygotes. The homozygous mutant mice did not suffer from reduced folliculogenesis or impacted follicle progression, unlike in the sheep homologue knockout experiments. The subfertility seen in the homozygous mutant phenotype was attributed to defective ovulation and reduced viability of embryos. Here it can be stated that BMP-15 is not as vital for normal female mouse fertility as it is for sheep. | https://en.wikipedia.org/wiki/Bone_morphogenetic_protein_15 |
In mice, the absence of L. reuteri has been causally linked to maternal diet. A gut microbial imbalance, lacking in L. reuteri, was linked to behavioral abnormalities consistent with autism in humans. These symptoms were reversible by supplementing L. reuteri. | https://en.wikipedia.org/wiki/Lactobacillus_reuteri |
In mice, the agouti gene encodes a paracrine signalling molecule that causes hair follicle melanocytes to synthesize the yellow pigment pheomelanin instead of the black or brown pigment eumelanin. Pleiotropic effects of constitutive expression of the mouse gene include adult-onset obesity, increased tumor susceptibility, and premature infertility. This gene is highly similar to the mouse gene and encodes a secreted protein that may (1) affect the quality of hair pigmentation, (2) act as an inverse agonist of alpha-melanocyte-stimulating hormone, (3) play a role in neuroendocrine aspects of melanocortin action, and (4) have a functional role in regulating lipid metabolism in adipocytes.In mice, the wild type agouti allele (A) presents a grey phenotype, however, many allele variants have been identified through genetic analyses, which result in a wide range of phenotypes distinct from the typical grey coat. The most widely studied allele variants are the lethal yellow mutation (Ay) and the viable yellow mutation (Avy) which are caused by ectopic expression of agouti. | https://en.wikipedia.org/wiki/Agouti_gene |
These mutations are also associated with yellow obese syndrome which is characterized by early onset obesity, hyperinsulinemia and tumorigenesis. The murine agouti gene locus is found on chromosome 2 and encodes a 131 amino acid protein. | https://en.wikipedia.org/wiki/Agouti_gene |
This protein signals the distribution of melanin pigments in epithelial melanocytes located at the base of hair follicles with expression being more sensitive on ventral hair than on dorsal hair. Agouti is not directly secreted in the melanocyte as it works as a paracrine factor on dermal papillae cells to inhibit release of melanocortin. Melanocortin acts on follicular melanocytes to increase production of eumelanin, a melanin pigment responsible for brown and black hair. When agouti is expressed, production of pheomelanin dominates, a melanin pigment that produces yellow or red colored hair. | https://en.wikipedia.org/wiki/Agouti_gene |
In mice, the genital ridge houses the transcript for SRY, the Y-chromosomal gene responsible for sex determination in mammals. The urogenital ridge is made up of the gonadal anlage and the mesonephros. The mesonephros is involved in the development of the testis, but its role is in differentiation, and not determination. This is indicated by the absence of SRY expression in the mesonephros. SRY expression is expressed exclusively in the developing gonad, lacking a presence in any other tissue in embryos or adults. | https://en.wikipedia.org/wiki/Genital_ridge |
In mice, the only 20-HETE- and 19-HETE-producing enzymes of the Cyp4a subfamily are two extensively homologous ones, Cyp4a12a and Cyp4a12b; Cyp4a12a is expressed in the male kidney in an androgen hormone-dependent manner. In rats, Cyp4a1, Cyp4a2, Cyp4a3, and Cyp4a8 make 20-HETE. The tissue distribution of these enzymes differs from those of humans making extrapolations from rodent studies to humans somewhat complicated. Mouse CYP2J9, rat CYP2J3, and sheep CYP2J metabolize arachidonic acid primarily to 19-HETE but also to smaller amounts of 20-HETE, and, in the case of the sheep enzyme, 18-HETE; human CYP2J2, however, is an epoxygenase, metabolizing arachidonic acid to epoxide products. | https://en.wikipedia.org/wiki/20-hydroxyarachidonic_acid |
In mice, the projection to CA1, and the subiculum all come primarily from EC layer III.According to Suh et al. (2011 Science 334:1415) the projection to CA3 and dentate gyrus in mice is primarily from layer II of entorhinal cortex, and forms a trisynaptic path with hippocampus (dentate gyrus to CA3 to CA1), distinguished from the direct (monosynaptic) perforant path from Layer III of entorhinal cortex to CA1 and subiculum. | https://en.wikipedia.org/wiki/Perforant_pathway |
In mice, there are 80 proteins in the brain, called "sleep need index phosphoproteins" (SNIPPs), which become more and more phosphorylated during waking hours, and are dephosphorylated during sleep. The phosphorylation is aided by the gene Sik3. A type of laboratory mouse (named Sleepy) possesses an altered version of this protein, which is called SLEEPY, where the protein is more active than the regular version. This results in the mice showing more slow-wave sleep activity during non-REM sleep—a reliable indicator that more sleep is met. Inhibition of the Sik3 gene decreases phosphorylation and slow-wave activity in both normal and modified mice. | https://en.wikipedia.org/wiki/Sleep_deficit |
In mice, these IELs are the most abundant at birth and with age their numbers decrease. In humans, these cells are present during gestation but are very rare in adulthood. TCRαβ+ IELs develop in thymus where they undergo agonist positive selection and thereby are self-reactive. Nevertheless, they have regulatory properties and protect against colitis in animal experiments. These cells are influenced by normal intestinal microbiota and vitamin D. NOD2 receptor expressed by antigen presenting cells and epithelial cells in the intestine recognizes microbes and triggers the production of IL-15 cytokine, which promotes TCRαβ+CD8αα+ IELs. | https://en.wikipedia.org/wiki/Intraepithelial_lymphocyte |
In mice, this gene has shown reduced expression in ageing animals causes cognitive long-term memory decline.In Dnmt3a-/- mice, many genes associated with HSC self-renewal increase in expression and some fail to be appropriately repressed during differentiation. This suggests abrogation of differentiation in hematopoietic stem cells (HSCs) and an increase in self-renewal cell-division instead. Indeed, it was found that differentiation was partially rescued if Dnmt3a-/- HSCs experienced an additional Ctnb1 knockdown – Ctnb1 codes for β-catenin, which participates in self-renewal cell division. | https://en.wikipedia.org/wiki/DNA_(cytosine-5)-methyltransferase_3A |
In micro Pumped-storage hydroelectricity (PSH), the same pump/PAT could be used for pumping and generating phases by changing rotational direction and speed. The best efficiency point in pumping usually differs from its reverse mode: a variable-frequency drive coupled to the motor/generator would be needed in order to change from pumping to generating mode and to react efficiently to the PSH load fluctuation. | https://en.wikipedia.org/wiki/Pump_as_turbine |
In microarray experiments DNA or RNA is labeled with either Cy3 or Cy5 that has been synthesized to carry an N-hydroxysuccinimidyl ester (NHS-ester) reactive group. Since NHS-esters react readily only with aliphatic amine groups, which nucleic acids lack, nucleotides have to be modified with aminoallyl groups. This is done through incorporating aminoallyl-modified nucleotides during synthesis reactions. A good ratio is a label every 60 bases such that the labels are not too close to each other, which would result in quenching effects. | https://en.wikipedia.org/wiki/Cyanine_dye |
In microbial cells, the cell walls are either Gram-positive or Gram-negative. These outcomes are based on the Gram Stain test. Gram-positive cell walls have thick peptidoglycan layer and no outer lipid membrane while Gram-negative bacteria have a thin peptidoglycan layer and an outer lipid membrane. Although a thick Gram-positive cell wall is advantageous, it is easier to attack as the peptidoglycan layer absorbs antibiotics and cleaning products. A Gram-negative cell wall is more resistant to such attacks and more difficult to destroy. | https://en.wikipedia.org/wiki/Microbial_cell_factory |
In microbial communities like soil, the C:N ratio is a key indicator as it describes a balance between energetic foods (represented by carbon) and material to build protein with (represented by nitrogen). An optimal C:N ratio of around 24:1 provides for higher microbial activity.The C:N ratio of soil can be modified by the addition of materials such as compost, manure, and mulch. A feedstock with a near-optimal C:N ratio will be consumed quickly. Any excess C will cause the N originally in the soil to be consumed, competing with the plant for nutrients (immobilization) – at least temporarily until the microbes die. | https://en.wikipedia.org/wiki/Carbon-to-nitrogen_ratio |
Any excess N, on the other hand, will usually just be left behind (mineralization), but too much excess may result in losses to leaching. The recommended C:N ratio for soil materials is therefore 30:1. A soil test may be done to find the C:N ratio of soil itself.The C:N ratio of microbes themselves is generally around 10:1. A lower ratio is correlated with higher soil productivity. | https://en.wikipedia.org/wiki/Carbon-to-nitrogen_ratio |
In microbial ecology, the principle of priority effect refers to the competitive advantage some microorganisms gain by colonizing a surface first. It is generally believed that primary colonization occurs by transmission from the mother or their breastmilk (vertical transmission), as well as the environment of the newborn (horizontal transmission). It has been found that at different locations in the oral cavity, different microbes are early colonizers. The very initial colonizers of teeth are considered to be Streptococcus, a genus of bacteria that are usually facultative anaerobes that can grow in both aerobic and anaerobic conditions. | https://en.wikipedia.org/wiki/Oral_ecology |
This is advantageous in an environment that is variably exposed to oxygen throughout the day as well as throughout the oral cavity. Despite over 700 unique species of bacteria being associated with the human mouth, in tooth plaque only between 7-9 "major players" have been repeatedly identified as early colonizers, including Actinomyces, Streptococcus, Neisseria, and Veillonella species. It is believed that the colonization of these specific genera of bacteria influence the stability and homeostasis of the resulting oral microflora. | https://en.wikipedia.org/wiki/Oral_ecology |
This colonization occurs by the construction of and adhesion to a pellicle made of glycoproteins from host saliva. Upon adhesion to the pellicle, early colonizing bacteria begin to produce the biofilm intended to anchor the colony to the tooth. As is common in microbiomes, this biofilm does not remain a single genera or species. | https://en.wikipedia.org/wiki/Oral_ecology |
In fact, the vast majority of relevant microbes perform co-aggregation within a biofilm. However, it is understood that not all microbes will co-aggregate together, and ammensal activity does occur between specific species, such as S. mutans and P. gingivalis. The interbacterial interactions as well as the interactions with the host teeth, oxygen conditions, and saliva are what compose bacterial oral ecology. | https://en.wikipedia.org/wiki/Oral_ecology |
In microbial fuel cells (MFCs), bacterial nanowires generate electricity via extracellular electron transport to the MFC's anode. Nanowire networks have been shown to enhance the electricity output of MFCs with efficient and long-range conductivity. In particular, bacterial nanowires of Geobacter sulfurreducens possess metallic-like conductivity, producing electricity at levels comparable to those of synthetic metallic nanostructures. When bacterial strains are genetically manipulated to boost nanowire formation, higher electricity yields are generally observed. | https://en.wikipedia.org/wiki/Bacterial_nanowires |
Coating the nanowires with metal oxides also further promotes electrical conductivity. Additionally, these nanowires can transport electrons up to centimeter-scale distances. Long-range electron transfer via microbial nanowire networks allows viable cells that are not in direct contact with an anode to contribute to electron flow.To date, the currency produced by bacterial nanowires is very low. Across a biofilm 7 micrometers thick, a current density of around 17 microamperes per square centimeter and a voltage of around 0.5 volts was reported. | https://en.wikipedia.org/wiki/Bacterial_nanowires |
In microbial genetics, a revertant is a mutant that has reverted to its former genotype or to the original phenotype by means of a suppressor mutation, or else by compensatory mutation somewhere in the gene (second site reversion). | https://en.wikipedia.org/wiki/Suppressor_mutation |
In microbiology and bacteriology, Gram stain (Gram staining or Gram's method), is a method of staining used to classify bacterial species into two large groups: gram-positive bacteria and gram-negative bacteria. The name comes from the Danish bacteriologist Hans Christian Gram, who developed the technique in 1884.Gram staining differentiates bacteria by the chemical and physical properties of their cell walls. Gram-positive cells have a thick layer of peptidoglycan in the cell wall that retains the primary stain, crystal violet. Gram-negative cells have a thinner peptidoglycan layer that allows the crystal violet to wash out on addition of ethanol. | https://en.wikipedia.org/wiki/Gram_Stain |
They are stained pink or red by the counterstain, commonly safranin or fuchsine. Lugol's iodine solution is always added after addition of crystal violet to strengthen the bonds of the stain with the cell membrane. | https://en.wikipedia.org/wiki/Gram_Stain |
Gram staining is almost always the first step in the identification of a bacterial group. While Gram staining is a valuable diagnostic tool in both clinical and research settings, not all bacteria can be definitively classified by this technique. This gives rise to gram-variable and gram-indeterminate groups. | https://en.wikipedia.org/wiki/Gram_Stain |
In microbiology and planktology, a theca is a subcellular structural component out of which the frustules of diatoms and dinoflagellates are constructed. | https://en.wikipedia.org/wiki/Theca |
In microbiology and virology, the term variant or genetic variant is used to describe a subtype of a microorganism that is genetically distinct from a main strain, but not sufficiently different to be termed a distinct strain. A similar distinction is made in botany between different cultivated varieties of a species of plant, termed cultivars. | https://en.wikipedia.org/wiki/Variant_(biology) |
In microbiology laboratories, E. cloacae is frequently grown at 30°C on nutrient agar or at 35°C in tryptic soy broth. It is a rod-shaped, Gram-negative bacterium, is facultatively anaerobic, and bears peritrichous flagella. It is oxidase-negative and catalase-positive. | https://en.wikipedia.org/wiki/Enterobacter_cloacae |
In microbiology, McFarland standards are used as a reference to adjust the turbidity of bacterial suspensions so that the number of bacteria will be within a given range to standardize microbial testing. An example of such testing is antibiotic susceptibility testing by measurement of minimum inhibitory concentration which is routinely used in medical microbiology and research. If a suspension used is too heavy or too dilute, an erroneous result (either falsely resistant or falsely susceptible) for any given antimicrobial agent could occur. Original McFarland standards were made by mixing specified amounts of barium chloride and sulfuric acid together. | https://en.wikipedia.org/wiki/McFarland_standards |
Mixing the two compounds forms a barium sulfate precipitate, which causes turbidity in the solution. A 0.5 McFarland standard is prepared by mixing 0.05 mL of 1.175% barium chloride dihydrate (BaCl2•2H2O), with 9.95 mL of 1% sulfuric acid (H2SO4).Now there are McFarland standards prepared from suspensions of latex particles, which lengthens the shelf life and stability of the suspensions. The standard can be compared visually to a suspension of bacteria in sterile saline or nutrient broth. | https://en.wikipedia.org/wiki/McFarland_standards |
If the bacterial suspension is too turbid, it can be diluted with more diluent. If the suspension is not turbid enough, more bacteria can be added. McFarland nephelometer standards:{2} *at wavelength of 600 nm McFarland latex standards from Hardy Diagnostics (2014-12-10), measured at the UCSF DeRisi Lab: | https://en.wikipedia.org/wiki/McFarland_standards |
In microbiology, a cell spreader or plate spreader is a tool used to smoothly spread cells and bacteria on a culture plate, such as a petri dish. Cell spreaders can be made from glass, plastic, or metal, and come in various shapes. A Drigalski spatula is a cell spreader consisting of a cylindrical rod or wire bent in the shape of a triangle with a handle. Another variant is a rod bent in L-shape. Extrusion molded versions can be T-shaped. | https://en.wikipedia.org/wiki/Cell_spreader |
In microbiology, a culture plate is a low flat-bottomed laboratory container for growing a layer of organisms such as bacteria, molds, and cells on a thin layer of nutrient medium. The most common types are the petri dish and multiwell plates. | https://en.wikipedia.org/wiki/Culture_plate |
In microbiology, colonial morphology refers to the visual appearance of bacterial or fungal colonies on an agar plate. Examining colonial morphology is the first step in the identification of an unknown microbe. The systematic assessment of the colonies' appearance, focusing on aspects like size, shape, colour, opacity, and consistency, provides clues to the identity of the organism, allowing microbiologists to select appropriate tests to provide a definitive identification. | https://en.wikipedia.org/wiki/Colonial_morphology |
In microbiology, colony-forming unit (CFU, cfu or Cfu) is a unit which estimates the number of microbial cells (bacteria, fungi, viruses etc.) in a sample that are viable, able to multiply via binary fission under the controlled conditions. Counting with colony-forming units requires culturing the microbes and counts only viable cells, in contrast with microscopic examination which counts all cells, living or dead. The visual appearance of a colony in a cell culture requires significant growth, and when counting colonies, it is uncertain if the colony arose from one cell or a group of cells. Expressing results as colony-forming units reflects this uncertainty. | https://en.wikipedia.org/wiki/Colony_forming_unit |
In microbiology, efflux is the moving of a variety of different compounds out of cells, such as antibiotics, heavy metals, organic pollutants, plant-produced compounds, quorum sensing signals, bacterial metabolites and neurotransmitters. All microorganisms, with a few exceptions, have highly conserved DNA sequences in their genome that encode efflux pumps. Efflux pumps actively move substances out of a microorganism, in a process known as active efflux, which is a vital part of xenobiotic metabolism. | https://en.wikipedia.org/wiki/Drug_efflux |
This active efflux mechanism is responsible for various types of resistance to bacterial pathogens within bacterial species - the most concerning being antibiotic resistance because microorganisms can have adapted efflux pumps to divert toxins out of the cytoplasm and into extracellular media.Efflux systems function via an energy-dependent mechanism (active transport) to pump out unwanted toxic substances through specific efflux pumps. Some efflux systems are drug-specific, whereas others may accommodate multiple drugs with small multidrug resistance (SMR) transporters.Efflux pumps are proteinaceous transporters localized in the cytoplasmic membrane of all kinds of cells. They are active transporters, meaning that they require a source of chemical energy to perform their function. Some are primary active transporters utilizing adenosine triphosphate hydrolysis as a source of energy, whereas others are secondary active transporters (uniporters, symporters, or antiporters) in which transport is coupled to an electrochemical potential difference created by pumping hydrogen or sodium ions into the cell. | https://en.wikipedia.org/wiki/Drug_efflux |
In microbiology, genes can move freely even between distantly related bacteria, possibly extending to the whole bacterial domain. As a rule of thumb, microbiologists have assumed that kinds of Bacteria or Archaea with 16S ribosomal RNA gene sequences more similar than 97% to each other need to be checked by DNA-DNA hybridisation to decide if they belong to the same species or not. This concept was narrowed in 2006 to a similarity of 98.7%.DNA-DNA hybridisation is outdated, and results have sometimes led to misleading conclusions about species, as with the pomarine and great skua. Modern approaches compare sequence similarity using computational methods. | https://en.wikipedia.org/wiki/DNA_metabarcoding |
In microbiology, genes can move freely even between distantly related bacteria, possibly extending to the whole bacterial domain. As a rule of thumb, microbiologists have assumed that members of Bacteria or Archaea with 16S ribosomal RNA gene sequences more similar than 97% to each other need to be checked by DNA–DNA hybridisation to decide if they belong to the same species. This concept was narrowed in 2006 to a similarity of 98.7%.The average nucleotide identity method quantifies genetic distance between entire genomes, using regions of about 10,000 base pairs. With enough data from genomes of one genus, algorithms can be used to categorize species, as for Pseudomonas avellanae in 2013, and for all sequenced bacteria and archaea since 2020.DNA barcoding has been proposed as a way to distinguish species suitable even for non-specialists to use. | https://en.wikipedia.org/wiki/Biological_species |
One of the barcodes is a region of mitochondrial DNA within the gene for cytochrome c oxidase. A database, Barcode of Life Data System, contains DNA barcode sequences from over 190,000 species. However, scientists such as Rob DeSalle have expressed concern that classical taxonomy and DNA barcoding, which they consider a misnomer, need to be reconciled, as they delimit species differently. Genetic introgression mediated by endosymbionts and other vectors can further make barcodes ineffective in the identification of species. | https://en.wikipedia.org/wiki/Biological_species |
In microbiology, genetics, cell biology, and molecular biology, competence is the ability of a cell to alter its genetics by taking up extracellular ("naked") DNA from its environment in the process called transformation. Competence may be differentiated between natural competence, a genetically specified ability of bacteria which is thought to occur under natural conditions as well as in the laboratory, and induced or artificial competence, which arises when cells in laboratory cultures are treated to make them transiently permeable to DNA. Competence allows for rapid adaptation and DNA repair of the cell. This article primarily deals with natural competence in bacteria, although information about artificial competence is also provided. | https://en.wikipedia.org/wiki/Competent_cell |
In microbiology, hydrodynamic focusing is a technique used to provide more accurate results when using flow cytometers or Coulter counters for determining the size of bacteria or cells. | https://en.wikipedia.org/wiki/Hydrodynamic_focusing |
In microbiology, in the context of a sterilization procedure, the D-value or decimal reduction time (or decimal reduction dose) is the time (or dose of an antimicrobial drug) required, at a given condition (e.g. temperature) or set of conditions, to achieve a log reduction, that is, to kill 90%(or 1 log) of relevant microorganisms. A D-value is denoted with the capital letter "D". Thus, after an exposure time of 1 D, only 10% of the organisms originally present in a microbial colony would remain. The term originated in assessments of microbes' thermal resistance and in thermal death time analysis; however, it now has analogous uses in other microbial resistance and death rate applications, such as for ethylene oxide and radiation processing. | https://en.wikipedia.org/wiki/D-value_(microbiology) |
In microbiology, in vivo is often used to refer to experimentation done in a whole organism, rather than in live isolated cells, for example, cultured cells derived from biopsies. In this situation, the more specific term is ex vivo. Once cells are disrupted and individual parts are tested or analyzed, this is known as in vitro. | https://en.wikipedia.org/wiki/In_vivo |
In microbiology, methyl red is used in the methyl red test (MR test), used to identify bacteria producing stable acids by mechanisms of mixed acid fermentation of glucose (cf. Voges–Proskauer test). The MR test, the "M" portion of the four IMViC tests, is used to identify enteric bacteria based on their pattern of glucose metabolism. All enterics initially produce pyruvic acid from glucose metabolism. Some enterics subsequently use the mixed acid pathway to metabolize pyruvic acid to other acids, such as lactic, acetic, and formic acids. | https://en.wikipedia.org/wiki/Methyl_red |
These bacteria are called methyl-red positive and include Escherichia coli and Proteus vulgaris. Other enterics subsequently use the butylene glycol pathway to metabolize pyruvic acid to neutral end products. These bacteria are called methyl-red-negative and include Serratia marcescens and Enterobacter aerogenes. | https://en.wikipedia.org/wiki/Methyl_red |
In microbiology, pleomorphism (from Ancient Greek πλέω-, pléō, "more", and -μορφή, morphḗ, form), also pleiomorphism, is the ability of some microorganisms to alter their morphology, biological functions or reproductive modes in response to environmental conditions. Pleomorphism has been observed in some members of the Deinococcaceae family of bacteria. The modern definition of pleomorphism in the context of bacteriology is based on variation of morphology or functional methods of the individual cell, rather than a heritable change of these characters as previously believed. | https://en.wikipedia.org/wiki/Pleomorphism_(microbiology) |
In microbiology, serologic tests are used to determine if a person has antibodies against a specific pathogen, or to detect antigens associated with a pathogen in a person's sample. Serologic tests are especially useful for organisms that are difficult to culture by routine laboratory methods, like Treponema pallidum (the causative agent of syphilis), or viruses.The presence of antibodies against a pathogen in a person's blood indicates that they have been exposed to that pathogen. Most serologic tests measure one of two types of antibodies: immunoglobulin M (IgM) and immunoglobulin G (IgG). IgM is produced in high quantities shortly after a person is exposed to the pathogen, and production declines quickly thereafter. | https://en.wikipedia.org/wiki/Serology |
IgG is also produced on the first exposure, but not as quickly as IgM. On subsequent exposures, the antibodies produced are primarily IgG, and they remain in circulation for a prolonged period of time.This affects the interpretation of serology results: a positive result for IgM suggests that a person is currently or recently infected, while a positive result for IgG and negative result for IgM suggests that the person may have been infected or immunized in the past. Antibody testing for infectious diseases is often done in two phases: during the initial illness (acute phase) and after recovery (convalescent phase). The amount of antibody in each specimen (antibody titer) is compared, and a significantly higher amount of IgG in the convalescent specimen suggests infection as opposed to previous exposure. False negative results for antibody testing can occur in people who are immunosuppressed, as they produce lower amounts of antibodies, and in people who receive antimicrobial drugs early in the course of the infection. | https://en.wikipedia.org/wiki/Serology |
In microbiology, sterility assurance level (SAL) is the probability that a single unit that has been subjected to sterilization nevertheless remains nonsterile. It is never possible to prove that all organisms have been destroyed, as the likelihood of survival of an individual microorganism is never zero. So SAL is used to express the probability of the survival. | https://en.wikipedia.org/wiki/Sterility_assurance_level |
For example, medical device manufacturers design their sterilization processes for an extremely low SAL, such as 10−6, which is a 1 in 1,000,000 chance of a non-sterile unit. SAL also describes the killing efficacy of a sterilization process. A very effective sterilization process has a very low SAL. | https://en.wikipedia.org/wiki/Sterility_assurance_level |
In microbiology, streaking is a technique used to isolate a pure strain from a single species of microorganism, often bacteria. Samples can then be taken from the resulting colonies and a microbiological culture can be grown on a new plate so that the organism can be identified, studied, or tested. The modern streak plate method has progressed from the efforts of Robert Koch and other microbiologists to obtain microbiological cultures of bacteria in order to study them. The dilution or isolation by streaking method was first developed by Loeffler and Gaffky in Koch's laboratory, which involves the dilution of bacteria by systematically streaking them over the exterior of the agar in a Petri dish to obtain isolated colonies which will then grow into quantity of cells, or isolated colonies. If the agar surface grows microorganisms which are all genetically same, the culture is then considered as a microbiological culture. | https://en.wikipedia.org/wiki/Streaking_(microbiology) |
In microbiology, the cultures are incubated and assessed by eye, bypassing tedious colony counting or expensive and tedious microscopic counts. Presumptive, confirmative and completed tests are a part of MPN.In molecular biology, a common application involves DNA templates diluted into polymerase chain reactions (PCR). Reactions only proceed when a template is present, allowing for a form of quantitative PCR, to assess the original concentration of template molecules. Another application involves diluting enzyme stocks into solution containing a chromogenic substrate, or diluting antigens into solutions for ELISA (Enzyme-Linked ImmunoSorbent Assay) or some other antibody cascade detection reaction, to measure the original concentration of the enzyme or antigen. | https://en.wikipedia.org/wiki/Most_probable_number |
In microbiology, the minimum inhibitory concentration (MIC) is the lowest concentration of a chemical, usually a drug, which prevents visible in vitro growth of bacteria or fungi. MIC testing is performed in both diagnostic and drug discovery laboratories.The MIC is determined by preparing a dilution series of the chemical, adding agar or broth, then inoculating with bacteria or fungi, and incubating at a suitable temperature. The value obtained is largely dependent on the susceptibility of the microorganism and the antimicrobial potency of the chemical, but other variables can affect results too. The MIC is often expressed in micrograms per milliliter (μg/mL) or milligrams per liter (mg/L). | https://en.wikipedia.org/wiki/Minimum_inhibitory_concentration |
In diagnostic labs, MIC test results are used to grade microbes as "S" (susceptible or responding to a standard dosing regimen), "I" (intermediate or requiring increased exposure) or "R" (resistant). These grades are assigned based on agreed upon values called breakpoints. Breakpoints are published by standards development organizations such as the U.S. | https://en.wikipedia.org/wiki/Minimum_inhibitory_concentration |
Clinical and Laboratory Standards Institute (CLSI), the British Society for Antimicrobial Chemotherapy (BSAC) and the European Committee on Antimicrobial Susceptibility Testing (EUCAST). The purpose of measuring MICs and grading microbes is to enable physicians to prescribe the most appropriate antimicrobial treatment. The first step in drug discovery is often measurement of the MICs of biological extracts, isolated compounds or large chemical libraries against bacteria and fungi of interest. | https://en.wikipedia.org/wiki/Minimum_inhibitory_concentration |
MIC values provide a quantitative measure of an extract or compound’s antimicrobial potency. The lower the MIC, the more potent the antimicrobial. When in vitro toxicity data is available, MICs can also be used to calculate selectivity index values, a measure of off-target to target toxicity. | https://en.wikipedia.org/wiki/Minimum_inhibitory_concentration |
In microbiology, the multiplicity of infection or MOI is the ratio of agents (e.g. phage or more generally virus, bacteria) to infection targets (e.g. cell). For example, when referring to a group of cells inoculated with virus particles, the MOI is the ratio of the number of virus particles to the number of target cells present in a defined space. | https://en.wikipedia.org/wiki/Multiplicity_of_Infection |
In microbiology, the oxidase test is used as a phenotypic characteristic for the identification of bacterial strains; it determines whether a given bacterium produces cytochrome oxidases (and therefore utilizes oxygen with an electron transfer chain). The test is used to determine whether a bacterium is an aerobe or anaerobe. However a bacterium that is Oxidase negative is not necessarily anaerobic, instead showing the bacterium does not possess cytochrome c oxidase. | https://en.wikipedia.org/wiki/Oxidase |
In microbiology, the phenotypic testing of mycobacteria uses a number of methods. The most-commonly used phenotypic tests to identify and distinguish Mycobacterium strains and species from each other are described below. | https://en.wikipedia.org/wiki/Phenotypic_testing_of_Mycobacteria |
In microbiology, the phyllosphere is the total above-ground surface of a plant when viewed as a habitat for microorganisms. The phyllosphere can be further subdivided into the caulosphere (stems), phylloplane (leaves), anthosphere (flowers), and carposphere (fruits). The below-ground microbial habitats (i.e. the thin-volume of soil surrounding root or subterranean stem surfaces) are referred to as the rhizosphere and laimosphere. Most plants host diverse communities of microorganisms including bacteria, fungi, archaea, and protists . Some are beneficial to the plant, others function as plant pathogens and may damage the host plant or even kill it. | https://en.wikipedia.org/wiki/Phyllosphere |
In microbiology, the term isolation refers to the separation of a strain from a natural, mixed population of living microbes, as present in the environment, for example in water or soil, or from living beings with skin flora, oral flora or gut flora, in order to identify the microbe(s) of interest. Historically, the laboratory techniques of isolation first developed in the field of bacteriology and parasitology (during the 19th century), before those in virology during the 20th century. | https://en.wikipedia.org/wiki/Isolation_(microbiology) |
In microeconomic theory, cost-minimization by consumers and by firms implies the existence of supply and demand correspondences for which market clearing equilibrium prices exist, if there are large numbers of consumers and producers. Under convexity assumptions or under some marginal-cost pricing rules, each equilibrium will be Pareto efficient: In large economies, non-convexity also leads to quasi-equilibria that are nearly efficient. However, the concept of market equilibrium has been criticized by Austrians, post-Keynesians and others, who object to applications of microeconomic theory to real-world markets, when such markets are not usefully approximated by microeconomic models. | https://en.wikipedia.org/wiki/Heterodox_economics |
Heterodox economists assert that micro-economic models rarely capture reality. Mainstream microeconomics may be defined in terms of optimization and equilibrium, following the approaches of Paul Samuelson and Hal Varian. On the other hand, heterodox economics may be labeled as falling into the nexus of institutions, history, and social structure. | https://en.wikipedia.org/wiki/Heterodox_economics |
In microeconomic theory, productive efficiency (or production efficiency) is a situation in which the economy or an economic system (e.g., bank, hospital, industry, country) operating within the constraints of current industrial technology cannot increase production of one good without sacrificing production of another good. In simple terms, the concept is illustrated on a production possibility frontier (PPF), where all points on the curve are points of productive efficiency. An equilibrium may be productively efficient without being allocatively efficient — i.e. it may result in a distribution of goods where social welfare is not maximized (bearing in mind that social welfare is a nebulous objective function subject to political controversy). Productive efficiency is an aspect of economic efficiency that focuses on how to maximize output of a chosen product portfolio, without concern for whether your product portfolio is making goods in the right proportion; in misguided application, it will aid in manufacturing the wrong basket of outputs faster and cheaper than ever before. | https://en.wikipedia.org/wiki/Productive_efficiency |
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