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Bristle	Synthetic types	Synthetic materials such as nylon are also used to make bristles in items such as brooms and sweepers. Bristles are often used to make brushes for cleaning purposes, as they are strongly abrasive; common examples include the toothbrush and toilet brush. The bristle brush and the scrub brush are common household cleaning tools, often used to remove dirt or grease from pots and pans. Bristles are also used on brushes other than for cleaning, notably paintbrushes.
Bristle	Synthetic types	Bristles are distinguished as flagged (split, bushy ends) or unflagged; these are also known as flocked or unflocked bristles. In cleaning applications, flagged bristles are suited for dry cleaning (due to picking up dust better than unflagged), and unflagged suited for wet cleaning (due to flagged ends becoming dirty and matted when wet). In painting, flagged bristles yield more even application.
Bristle	Natural types	Bristles are found on pig breeds, instead of fur. Because the density is less than with fur, pigs are vulnerable to sunburn. One breed, the Tamworth pig, is endowed with a very dense bristle structure such that sunburn damage to skin is minimized. Animals named for their bristles include bristlebirds, the bristle-thighed curlew, the bristle-spined porcupine, and the Trinity bristle snail.
Bristle	Natural types	Bristles also anchor worms to the soil to help them move.
Fingerspitzengefühl	Fingerspitzengefühl	Fingerspitzengefühl [ˈfɪŋɐˌʃpɪtsənɡəˌfyːl] is a German term, literally meaning "finger tips feeling" and meaning intuitive flair or instinct, which has been adopted by the English language as a loanword. It describes a great situational awareness, and the ability to respond most appropriately and tactfully. It can also be applied to diplomats, bearers of bad news, or to describe a superior ability to respond to an escalated situation. The term is sometimes used to describe the instinctive play of certain football players.
Fingerspitzengefühl	Social context	In social context, Fingerspitzengefühl suggests a combination of "tact, diplomacy and a certain amount of sensitivity to the feelings of others". It is a quality that can enable a person to "negotiate tricky social situations". In literal terms, it means a physical skill appearing to be controlled by the nerves in the extremities, as in a machinist hand lathing steel to micrometer tolerances.
Fingerspitzengefühl	Military context	In military terminology, it is used for the stated ability of some military commanders, such as Field-Marshal Erwin Rommel, to describe "the instinctive and immediate response to battle situations", a quality needed to maintain, with great accuracy and attention to detail, an ever-changing operational and tactical situation by maintaining a mental map of the battlefield. The idiom is intended to evoke a military commander who is in such intimate communication with the battlefield that it is as though he has a fingertip on each critical point. In this sense the term is synonymous with the English expression of "keeping one's finger on the pulse", and was expressed in the 18th and 19th centuries as "having a feel for combat".
Fingerspitzengefühl	Military context	The term is only figurative, and cannot in itself give a realistic picture of the ability being described. It is cognitively related to personal possession of multiple intelligences, notably those pertinent to visual and spatial data processing. The term suggests that in addition to any discursive processing of information that the commander may be conducting (such as mentally considering a specific plan), the commander is automatically establishing cognitive relationships between disparate pieces of information as they arrive, and is able to immediately re-synthesise their mental model of the battlefield.
Fingerspitzengefühl	Military context	Even though there is no physical connection between the commander and his troops, other than conduits for discursive information such as radio signals, it is as if the commander had their own sensitive presence in each spot.
Fingerspitzengefühl	Military context	One of the functions of a static map is to allow a traveler to decide upon a course of action suitable for getting from one point to another. In times of war, the terrain and the troops and weapons deployed upon it can be changed much more rapidly than cartographers can change their maps. A commander with Fingerspitzengefühl would hold such a map in their mind, and adjust it by incorporating any significant information that was received.
Fingerspitzengefühl	Military context	Colonel Mehta Basti Ram was said to have Fingerspitzengefühl.
Fingerspitzengefühl	Related concepts	The concept may be compared to ideas about intuition and neural net programming. The same phenomenon, but conceptualized in a radically different way, seems to be described by D.T. Suzuki in swordsmanship teaching stories recounted in his Zen and Japanese Culture, and given in analytical detail in Zen Buddhism and Psychoanalysis.
Flame ionization detector	Flame ionization detector	A flame ionization detector (FID) is a scientific instrument that measures analytes in a gas stream. It is frequently used as a detector in gas chromatography. The measurement of ion per unit time make this a mass sensitive instrument. Standalone FIDs can also be used in applications such as landfill gas monitoring, fugitive emissions monitoring and internal combustion engine emissions measurement in stationary or portable instruments.
Flame ionization detector	History	The first flame ionization detectors were developed simultaneously and independently in 1957 by McWilliam and Dewar at Imperial Chemical Industries of Australia and New Zealand (ICIANZ, see Orica history) Central Research Laboratory, Ascot Vale, Melbourne, Australia. and by Harley and Pretorius at the University of Pretoria in Pretoria, South Africa.In 1959, Perkin Elmer Corp. included a flame ionization detector in its Vapor Fractometer.
Flame ionization detector	Operating principle	The operation of the FID is based on the detection of ions formed during combustion of organic compounds in a hydrogen flame. The generation of these ions is proportional to the concentration of organic species in the sample gas stream.
Flame ionization detector	Operating principle	To detect these ions, two electrodes are used to provide a potential difference. The positive electrode acts as the nozzle head where the flame is produced. The other, negative electrode is positioned above the flame. When first designed, the negative electrode was either tear-drop shaped or angular piece of platinum. Today, the design has been modified into a tubular electrode, commonly referred to as a collector plate. The ions thus are attracted to the collector plate and upon hitting the plate, induce a current. This current is measured with a high-impedance picoammeter and fed into an integrator. The manner in which the final data is displayed is based on the computer and software. In general, a graph is displayed that has time on the x-axis and total ion on the y-axis.
Flame ionization detector	Operating principle	The current measured corresponds roughly to the proportion of reduced carbon atoms in the flame. Specifically how the ions are produced is not necessarily understood, but the response of the detector is determined by the number of carbon atoms (ions) hitting the detector per unit time. This makes the detector sensitive to the mass rather than the concentration, which is useful because the response of the detector is not greatly affected by changes in the carrier gas flow rate.
Flame ionization detector	Response factor	FID measurements are usually reported "as methane," meaning as the quantity of methane which would produce the same response. The same quantity of different chemicals produces different amounts of current, depending on the elemental composition of the chemicals. The response factor of the detector for different chemicals can be used to convert current measurements into actual amounts of each chemical.
Flame ionization detector	Response factor	Hydrocarbons generally have response factors that are equal to the number of carbon atoms in their molecule (more carbon atoms produce greater current), while oxygenates and other species that contain heteroatoms tend to have a lower response factor. Carbon monoxide and carbon dioxide are not detectable by FID. FID measurements are often labelled "total hydrocarbons" or "total hydrocarbon content" (THC), although a more accurate name would be "total volatile hydrocarbon content" (TVHC), as hydrocarbons which have condensed out are not detected, even though they are important, for example safety when handling compressed oxygen.
Flame ionization detector	Description	The design of the flame ionization detector varies from manufacturer to manufacturer, but the principles are the same. Most commonly, the FID is attached to a gas chromatography system.
Flame ionization detector	Description	The eluent exits the gas chromatography column (A) and enters the FID detector’s oven (B). The oven is needed to make sure that as soon as the eluent exits the column, it does not come out of the gaseous phase and deposit on the interface between the column and FID. This deposition would result in loss of eluent and errors in detection. As the eluent travels up the FID, it is first mixed with the hydrogen fuel (C) and then with the oxidant (D). The eluent/fuel/oxidant mixture continues to travel up to the nozzle head where a positive bias voltage exists. This positive bias helps to repel the oxidized carbon ions created by the flame (E) pyrolyzing the eluent. The ions (F) are repelled up toward the collector plates (G) which are connected to a very sensitive ammeter, which detects the ions hitting the plates, then feeds that signal to an amplifier, integrator, and display system(H). The products of the flame are finally vented out of the detector through the exhaust port (J).
Flame ionization detector	Advantages and disadvantages	Advantages Flame ionization detectors are used very widely in gas chromatography because of a number of advantages. Cost: Flame ionization detectors are relatively inexpensive to acquire and operate. Low maintenance requirements: Apart from cleaning or replacing the FID jet, these detectors require little maintenance. Rugged construction: FIDs are relatively resistant to misuse. Linearity and detection ranges: FIDs can measure organic substance concentration at very low (10−13 g/s) and very high levels, having a linear response range of 107 g/s.
Flame ionization detector	Advantages and disadvantages	Disadvantages Flame ionization detectors cannot detect inorganic substances and some highly oxygenated or functionalized species like infrared and laser technology can. In some systems, CO and CO2 can be detected in the FID using a methanizer, which is a bed of Ni catalyst that reduces CO and CO2 to methane, which can be in turn detected by the FID. The methanizer is limited by its inability to reduce compounds other than CO and CO2 and its tendency to be poisoned by a number of chemicals commonly found in gas chromatography effluents.
Flame ionization detector	Advantages and disadvantages	Another important disadvantage is that the FID flame oxidizes all oxidizable compounds that pass through it; all hydrocarbons and oxygenates are oxidized to carbon dioxide and water and other heteroatoms are oxidized according to thermodynamics. For this reason, FIDs tend to be the last in a detector train and also cannot be used for preparatory work.
Flame ionization detector	Advantages and disadvantages	Alternative solution An improvement to the methanizer is the Polyarc reactor, which is a sequential reactor that oxidizes compounds before reducing them to methane. This method can be used to improve the response of the FID and allow for the detection of many more carbon-containing compounds. The complete conversion of compounds to methane and the now equivalent response in the detector also eliminates the need for calibrations and standards because response factors are all equivalent to those of methane. This allows for the rapid analysis of complex mixtures that contain molecules where standards are not available.
Social dining	Social dining	Social dining (by a group of people) is meeting either at someone's place or at restaurant to enjoy a meal together. It is a philosophy of using meals specifically as a means to connect with others: eat to socialize. A brunch, dinner or supper party are popular examples of places to socially gather over food.Social dining differs from a dining club in the sense that it is not exclusive, but promotes an inclusive atmosphere. Friends and strangers alike can share the social dining experience.
Social dining	History	Social dining dates back to Ancient Greek cuisine when meals would be prepared for the purpose of gathering together during festivals or commemorations.
Social dining	Influence of Technology	Technology has made social dining a sharable experience through real-time updates, uploaded images and check-ins (at someone's place or at the restaurant). Conversations about meals happen between people present and then are shared with those who are connected to them afar. Websites such as Twitter, Facebook, FourSquare and Gastronaut all encourage people to discuss their dining activities in a virtual, social space. Apps can be downloaded to a user's smartphone to share updates.
Social dining	Influence of Technology	Some web-based services get people together to share a social meal, even to join local families for a social dining experience while travelling, to truly experience the local culture and culinary. There are also other social dining networks that let people do group meals at the homes of their users. Another way to experience social dining is by visiting a supper club.
Social dining	Influence of Technology	Social dining experiences can also be a source of revenue for host that enable them through different kind of website, those can be associated to airbnb business model.
Minitran	Minitran	Minitran is a commercial psychiatric drug (tranquilliser and antidepressant) manufactured in Greece by Adelco S.A. and sold in form of yellow-coloured sugar-coated tablets.It contains Amitriptyline hydrochloride and Perphenazine. It is sold in the following forms: Minitran 2-10: 2 mg Perphenazine and 10 mg Amitriptyline hydrochloride in each tablet. Minitran 2-25: 2 mg Perphenazine and 25 mg Amitriptyline hydrochloride in each tablet. Minitran 4-10: 4 mg Perphenazine and 10 mg Amitriptyline hydrochloride in each tablet. Minitran 4-25: 4 mg Perphenazine and 25 mg Amitriptyline hydrochloride in each tablet.Minitran is also a pharmaceutical drug for the treatment of Angina, manufactured by 3M.
Minitran	Minitran	It contains glyceryl trinitrate and is sold in patch form. It is sold in the following strengths: Minitran 5 contains 18 mg of glyceryl trinitrate and delivers 5 mg in 24 hours Minitran 10: contains 36 mg of glyceryl trinitrate and delivers 10 mg in 24 hours Minitran 15: contains 54 mg of glyceryl trinitrate and delivers 15 mg in 24 hoursIt is also marketed as Discotrine in some countries.
Tick (pejorative)	Tick (pejorative)	Tick, often also as the plural ticks, is a common term used in Germany's right-wing extremist environment to degrade and insult those who think differently, especially leftists and Punks.According to today's right-wing extremist ideology so-called ticks are seen as the main concept of the enemy and are regarded as "un-Germans ideologicall and culturally". The degradation of humans to ticks, i.e. parasites, ties in with the animal metaphors used in the language of National Socialism. The terms "pests" and "Jewish parasites" were widespread in National Socialism. Today these pest metaphors are also widely used in right-wing extremist music and can also be seen as indirect incitement for killing. Violence committed by right-wing extremists was often described as "tick slapping".In the punk or rapscene the term is used as an antonym and sometimes as a self-designation. The punk bands "Se Sichelzecken" and "ESA-Zecken" made the swearword part of their names.
Tick (pejorative)	Tick (pejorative)	In recent years the term tick has been made popular and has been used as a self-designation in the musical genre of tick rap. Some followers of the football club FC St. Pauli, especially in the ultra scene, also say "Wir sind Zecken" (we are ticks) in fan chants.In the aftermath of the Sea-Watch 3 affair and its intrusion into the port of Lampedusa the Italian Minister of the Interior, Matteo Salvini, insulted the German captain Carola Rackete as a "German tick" at a party celebration of the Lega in Barzago in July 2019.
Dwork family	Dwork family	In algebraic geometry, a Dwork family is a one-parameter family of hypersurfaces depending on an integer n, studied by Bernard Dwork. Originally considered by Dwork in the context of local zeta-functions, such families have been shown to have relationships with mirror symmetry and extensions of the modularity theorem.
Dwork family	Definition	The Dwork family is given by the equations x1n+x2n+⋯+xnn=−nλx1x2⋯xn, for all n≥1
PTPRK	PTPRK	Receptor-type tyrosine-protein phosphatase kappa is an enzyme that in humans is encoded by the PTPRK gene. PTPRK is also known as PTPkappa and PTPκ.
PTPRK	Function	The protein encoded by this gene is a member of the protein tyrosine phosphatase (PTP) family. Protein tyrosine phosphatases are protein enzymes that remove phosphate moieties from tyrosine residues on other proteins. Tyrosine kinases are enzymes that add phosphates to tyrosine residues, and are the opposing enzymes to PTPs. PTPs are known to be signaling molecules that regulate a variety of cellular processes including cell growth, differentiation, mitotic cycle, and oncogenic transformation.
PTPRK	Function	The human PTPRK gene is located on the long arm of chromosome 6, a putative tumor suppressor region of the genome.
PTPRK	Function	During development The same reporter construct used by Shen and colleagues, and described above was created by Skarnes et al. during a screen to identify genes important in mouse development. The transgenic mouse was created by combining a β-galactosidase (β-gal) reporter gene with a signal sequence and the transmembrane domain of the type I transmembrane protein CD4. If the transgene was incorporated into a gene with a signal sequence, β-gal activity would remain in the cytosol of the cell and therefore be active. If the reporter gene was incorporated into a gene that lacked a signal sequence, β-gal activity would be in the ER where it would lose β-gal activity. This construct inserted into the phosphatase domain of PTPkappa. Mice generated from these ES cells were viable, suggesting that PTPkappa phosphatase activity is not necessary for embryonic development.Additional studies have suggested a function for PTPkappa during nervous system development. PTPkappa promotes neurite outgrowth from embryonic cerebellar neurons, and thus may be involved in axonal extension or guidance in vivo. Neurites are extensions from neurons that can be considered the in vitro equivalent of axons and dendrites. The extension of cerebellar neurites on purified PTPkappa fusion proteins was demonstrated to require Grb2 and MEK1 activity.
PTPRK	Function	In T cells PTPkappa has also been shown to regulate CD4+ positive T cell development. PTPkappa and the THEMIS gene are both deleted in the rat Long-Evans Cinnamon (LEC) strain, and are both required for the CD4+ T-cell deficiency observed in this strain of rats. Deletion of PTPkappa was shown to generate T-helper immunodeficiency in the LEC strain.By expressing a dominant negative form of PTPkappa or by using short-hairpin RNA for PTPkappa in bone-marrow derived stem cells, CD4(+) T cells development is inhibited. PTPkappa likely regulates T-cell development by positively regulating ERK1/2 phosphorylation via the regulation of MEK1/2 and c-Raf phosphorylation.
PTPRK	Function	Cadherin-catenin signaling PTPkappa is localized to cell-cell contact sites, where it colocalizes and co-immunoprecipitates with β-catenin and plakoglobin/γ-catenin β-catenin may be a PTPkappa substrate. The presence of full-length PTPkappa in melanoma cells decreases the level of free-cytosolic β-catenin, which consequently reduces the level of nuclear β-catenin and reduces the expression of the β-catenin-regulated genes, cyclin D1 and c-myc. Expression of ful-length PTPkappa in melanoma cells that normally lack its expression results in reduced cell migration and cell proliferation. Because the presence of PTPkappa at the cell membrane was shown to sequester β-catenin to the plasma membrane, these data suggest that one mechanism whereby PTPkappa functions as a tumor suppressor is by regulating the intracellular localization of free-β-catenin.The intracellular fragments of PTPkappa, PΔE and PIC, are catalytically active, and can also dephosphorylate β-catenin. Tyrosine phosphorylated β-catenin translocates to the cell nucleus and activates TCF-mediated transcription to promote cell proliferation and migration. While full-length PTPkappa antagonizes TCF-mediated transcription, the PIC fragment augments it, perhaps by regulating other proteins in TCF-mediated transcription. This suggests that phosphatase activity of the PIC fragment opposes that of full-length PTPkappa.PTPkappa interacts by co-immunoprecipitation with E-cadherin, α-catenin and β-catenin in pancreatic acinar cells prior to the dissolution of adherens junctions in a rat model of pancreatitis. The authors suggest that the presence of PTPkappa at the plasma membrane in association with the cadherin/catenin complex is important for the maintenance of adherens junction in pancreatic acinar cells, much as it was suggested above in melanoma cells.
PTPRK	Function	EGFR signaling Use of short interfering RNA (siRNA) of PTPkappa to reduce PTPkappa protein expression in the mammary epithelial cell line, MCF10A, resulted in increased cell proliferation. PTPkappa expression, conversely, was demonstrated to reduce cell proliferation in Chinese hamster ovary cells. The mechanism proposed to explain the influence of PTPkappa on cell proliferation is via PTPkappa dephosphorylation of the EGFR on tyrosines 1068 and 1173 directly. The reduction of PTPkappa expression in CHO cells with PTPkappa siRNA increased EGFR phosphorylation. Therefore, the hypothesis is that PTPkappa functions as a tumor suppressor gene by dephosphorylating and inactivating EGFR.In addition, glycosylation by N-acetylglucosaminyltransferase-V (GnT-V) has been shown to reduce full-length PTPkappa expression, likely via increasing its cleavage. This aberrant glycosylation has been shown to increase the phosphorylation of EGFR on tyrosine 1068, likely because of reduced plasma-membrane associated PTPkappa expression and hence reduced PTPkappa-mediated dephosphorylation of its membrane associated substrates, such as EGFR.
PTPRK	Structure	PTPkappa possesses an extracellular region, a single transmembrane region, and two tandem catalytic domains, and thus represents a receptor-type PTP (RPTP). The extracellular region contains a meprin-A5 antigen-PTP mu (MAM) domain, an Ig-like domain and four fibronectin type III-like repeats. PTPkappa is a member of the R2B subfamily of RPTPs, which includes RPTPM, RPTPT, and RPTPU. PTPkappa shares most sequence similarity with PTPmu and PTPrho.
PTPRK	Structure	Crystal structure analysis of the first phosphatase domain of PTPkappa demonstrates that it shares many conformational features with PTPmu, including an unhindered open conformation for the catalytically important WPD loop, and a phosphate binding loop for the active-site cysteine (Cys1083). PTPkappa exists as a monomer in solution, with the caveat that dimers of PTPkappa are observed depending on the nature of the buffer used.
PTPRK	Alternative splicing	Alternative splicing of exons 16, 17a, and 20a has been described for PTPRK. Two novel forms of PTPRK were identified from mouse full-length cDNA sequences and were predicted to result in two PTPkappa splice variants: a secreted form of PTPkappa and a membrane tethered form.
PTPRK	Homophilic binding	PTPkappa mediates homophilic cell-cell aggregation via its extracellular domain. PTPkappa only mediates binding between cells expressing PTPkappa (i.e. homophilic), and will not mediate cell aggregation between cells expressing PTPkappa, PTPmu or PTPrho (i.e. heterophilic).
PTPRK	Regulation	Proteolysis and N-glycosylation Full-length PTPkappa protein is cleaved by furin to generate two cleaved fragments that remain associated at the plasma membrane, an extracellular (E) subunit and an intracellular phosphatase (P) subunit. In response to high cell density or calcium influx following trifluoperazine (TFP) stimulation, PTPkappa is further cleaved by ADAM 10 to yield a shed extracellular fragment and a membrane tethered intracellular fragment, PΔE. The membrane tethered PΔE fragment is further cleaved by the gamma secretase complex to yield a membrane-released fragment, PIC, that can translocate to the cellular nucleus, where it is catalytically active.Glycosylation of the extracellular domain of PTPkappa was demonstrated to occur preferentially in WiDr colon cancer cells that over-express N-acetylglucosaminyl transferase V (GnT-V). Over-expression of GnT-V in these cells increased the cleavage and shedding of PTPkappa ectodomain and increased migration of WiDr cells in transwell assays. As a result of glycosylation of PTPkappa by GnT-V, EGFR was phosphorylated on tyrosine 1068 and activated, and is likely the cause of the increased cell migration observed following PTPkappa cleavage.Shedding of PTPkappa may also be regulated by the presence of galectin-3 binding protein, as has been shown in WiDr cells. The authors suggest that the ratio of galectin-3 binding protein to galectin 3 influences the cleavage and shedding of PTPkappa, although the exact mechanism of how these proteins regulate PTPkappa cleavage was not determined.
PTPRK	Regulation	By reactive oxygen species in cancer One mechanism whereby PTPkappa tyrosine phosphatase activity can be perturbed in cancer is via oxidative inhibition mediated by reactive oxygen species generated by either hydrogen peroxide in vitro or UV irradiation of skin cells in vivo. In cell-free assays, the presence of hydrogen peroxide reduces PTPkappa tyrosine phosphatase activity and increases EGFR tyrosine phosphorylation. UV-irradiation of primary human keratinocytes yields the same results, namely a reduction of PTPkappa tyrosine phosphatase activity and an increase in EGFR tyrosine phosphorylation. EGFR phosphorylation then leads to cell proliferation, suggesting that PTPkappa may function as a tumor suppressor in skin cancer in addition to melanoma.
PTPRK	Regulation	Expression PTPkappa is expressed in human keratinocytes. TGFβ1 is a growth inhibitor in human keratinocytes. Stimulation of the cultured human keratinocyte cell line, HaCaT, with TGFβ1 increases the levels of PTPkappa (PTPRK) mRNA as assayed by northern blot analysis. TGFβ1 also increased PTPkappa mRNA and protein in normal and tumor mammary cell lines. HER2 overexpression reduced PTPkappa mRNA and protein expression.
PTPRK	Clinical significance	Melanoma and skin cancer Expression analysis of PTPkappa mRNA in normal melanocytes and in melanoma cells and tissues demonstrated that PTPkappa is downregulated or absent 20% of the time in melanoma, suggesting that PTPkappa is a tumor suppressor gene in melanoma. A form of PTPkappa with a point mutation in the fourth fibronectin III repeat was identified to be a melanoma specific antigen recognized by CD4+ T cells in a melanoma patient with 10-year tumor-free survival after lymph node resection. This particular mutated form of PTPkappa was not identified in 10 other melanoma cell lines, and may thus represent a unique mutation in one patient.
PTPRK	Clinical significance	Lymphoma PTPkappa was also identified as the putative tumor suppressor gene commonly deleted in primary central nervous system lymphomas (PCNSLs).Downregulation of PTPkappa was found to occur following Epstein-Barr Virus (EBV) infection of Hodgkin's Lymphomas cells. Colorectal cancer Using a transposon-based genetic screen, researchers found that disruption of the PTPRK gene in gastrointestinal tract epithelium resulted in an intestinal lesion, classified as either an intraepithelial neoplasia, an adenocarcinoma or an adenoma. Lung cancer PTPRK mRNA was shown to be significantly reduced by RT-PCR in human lung cancer-derived cell lines. Prostate cancer PTPRK has also been shown to be downregulated in response to androgen stimulation in human LNCaP prostate cancer cells. The mechanism whereby PTPRK is downregulated is via the expression of a microRNA, miR-133b, which is upregulated in response to androgen stimulation.
PTPRK	Clinical significance	Breast cancer Patients with reduced PTPRK transcript expression have shorter breast cancer survival times and are more likely to have breast cancer metastases or to die from breast cancer. In an experimental model of breast cancer, PTPRK was reduced in breast cancer cell lines with PTPRK ribozymes. In these cells, adhesion to matrigel, transwell migration, and cell growth were all increased following the reduction of PTPRK expression, again supporting a function for PTPRK as a tumor suppressor.
PTPRK	Clinical significance	Glioma Assem and colleagues identified loss of heterozygosity (LOH) events in malignant glioma specimens, and identified PTPRK as a significant gene candidate in one LOH region. A significant correlation between the presence of PTPRK mutations and short patient survival time was observed. PTPRK was amplified from tumor cDNA to confirm the LOH observed. In these specimens, 6 different mutations were observed, two of which (one in each phosphatase domain) disrupted the enzymatic activity of PTPRK. Expression of wild-type PTPkappa in U87-MG and U251-MG cells resulted in a reduction in cell proliferation, migration and invasion. Expression of the variants of PTPkappa with mutations in the phosphatase domains, however, increased cell proliferation, migration and invasion, supporting a role for the involvement of the mutated variants of PTPkappa in tumorigenicity.
PTPRK	Clinical significance	In development In situ hybridization localized PTPkappa mRNA to the brain, lung, skeletal muscle, heart, placenta, liver, kidney and intestines during development. PTPkappa was also found to be expressed in the developing retina, in nestin-positive radial progenitor cells and later in development, in the ganglion cell layer, inner plexiform layer and outer segments of photoreceptors. PTPkappa protein is observed in neural progenitor cells and radial glial cells of the developing mouse superior colliculus, as well.In the adult rat brain, PTPkappa mRNA is highly expressed in regions of the brain with cellular plasticity and growth, such as the olfactory bulb, the hippocampus and the cerebral cortex. PTPkappa mRNA is also observed in the adult mouse cerebellum.Using a β-galactosidase (β-gal) reporter gene inserted into the phosphatase domain of the murine PTPkappa (PTPRK) gene, Shen and colleagues determined the detailed expression pattern of endogenous PTPRK. β-gal activity was observed in many areas of the adult forebrain, including layers II and IV, and to a lesser extent in layer VI of the cortex. β-gal activity was also observed in apical dendrites of cortical pyramidal cells, the granule layer of the olfactory and accessory olfactory bulbs, the anterior hypothalamus, paraventricular nucleus, and in granule and pyramidal layers of the dentate gyrus and CA 1-3 regions of the hippocampus. In the midbrain, β-gal was observed in the subthalamic nucleus, the superior and inferior colliculi and in the red nucleus. β-gal activity was also observed in the neural retina, in the inner nuclear layer and in small ganglion cells of the ganglion cell layer.
PTPRK	Interactions	PTPRK has been shown to interact with: Beta-catenin, E-cadherin (CDH-1), Epidermal growth factor receptor (EGFR), HER2, Plakoglobin, and α-catenin.
Reaction wheel	Reaction wheel	A reaction wheel (RW) is used primarily by spacecraft for three-axis attitude control, and does not require rockets or external applicators of torque. They provide a high pointing accuracy,: 362 and are particularly useful when the spacecraft must be rotated by very small amounts, such as keeping a telescope pointed at a star.
Reaction wheel	Reaction wheel	A reaction wheel is sometimes operated as (and referred to as) a momentum wheel, by operating it at a constant (or near-constant) rotation speed, to provide a satellite with a large amount of stored angular momentum. Doing so alters the spacecraft's rotational dynamics so that disturbance torques perpendicular to one axis of the satellite (the axis parallel to the wheel's spin axis) do not result directly in spacecraft angular motion about the same axis as the disturbance torque; instead, they result in (generally smaller) angular motion (precession) of that spacecraft axis about a perpendicular axis. This has the effect of tending to stabilize that spacecraft axis to point in a nearly-fixed direction,: 362 allowing for a less-complicated attitude control system. Satellites using this "momentum-bias" stabilization approach include SCISAT-1; by orienting the momentum wheel's axis to be parallel to the orbit-normal vector, this satellite is in a "pitch momentum bias" configuration.
Reaction wheel	Reaction wheel	A control moment gyroscope (CMG) is a related but different type of attitude actuator, generally consisting of a momentum wheel mounted in a one-axis or two-axis gimbal.: 362 When mounted to a rigid spacecraft, applying a constant torque to the wheel using one of the gimbal motors causes the spacecraft to develop a constant angular velocity about a perpendicular axis, thus allowing control of the spacecraft's pointing direction. CMGs are generally able to produce larger sustained torques than RWs with less motor heating, and are preferentially used in larger or more-agile (or both) spacecraft, including Skylab, Mir, and the International Space Station.
Reaction wheel	Theory	Reaction wheels are used to control the attitude of a satellite without the use of thrusters, which reduces the mass fraction needed for fuel.
Reaction wheel	Theory	They work by equipping the spacecraft with an electric motor attached to a flywheel, which, when its rotation speed is changed, causes the spacecraft to begin to counter-rotate proportionately through conservation of angular momentum. Reaction wheels can rotate a spacecraft only around its center of mass (see torque); they are not capable of moving the spacecraft from one place to another (see translational force).
Reaction wheel	Implementation	For three-axis control, reaction wheels must be mounted along at least three directions, with extra wheels providing redundancy to the attitude control system. A redundant mounting configuration could consist of four wheels along tetrahedral axes, or a spare wheel carried in addition to a three axis configuration.: 369 Changes in speed (in either direction) are controlled electronically by computer. The strength of the materials used in a reaction wheel determine the speed at which the wheel would come apart, and therefore how much angular momentum it can store.
Reaction wheel	Implementation	Since the reaction wheel is a small fraction of the spacecraft's total mass, easily controlled, temporary changes in its speed result in small changes in angle. The wheels therefore permit very precise changes in a spacecraft's attitude. For this reason, reaction wheels are often used to aim spacecraft carrying cameras or telescopes.
Reaction wheel	Implementation	Over time, reaction wheels may build up enough stored momentum to exceed the maximum speed of the wheel, called saturation, which will need to be canceled. Designers therefore supplement reaction wheel systems with other attitude control mechanisms. In the presence of a magnetic field (as in low Earth orbit), a spacecraft can employ magnetorquers (better known as torque rods) to transfer angular momentum to Earth through its planetary magnetic field.: 368 In the absence of a magnetic field, the most efficient practice is to use either high-efficiency attitude jets such as ion thrusters, or small, lightweight solar sails placed in locations away from the spacecraft's center of mass, such as on solar cell arrays or projecting masts.
Reaction wheel	Examples of spacecraft using reaction wheels	Beresheet Beresheet was launched on a Falcon 9 rocket on 22 February 2019 1:45 UTC, with the goal of landing on the Moon. Beresheet uses the low-energy transfer technique to save fuel. Since its fourth maneuver in its elliptical orbit, to prevent shakes when the amount of liquid fuel ran low, there was a need to use a reaction wheel.
Reaction wheel	Examples of spacecraft using reaction wheels	James Webb Space Telescope The James Webb Space Telescope has six reaction wheels built by Rockwell Collins Deutschland. LightSail 2 LightSail 2 was launched on 25 June 2019, focused around the concept of a solar sail. LightSail 2 uses a reaction wheel system to change orientation by very small amounts, allowing it to receive different amounts of momentum from the light across the sail, resulting in a higher altitude.
Reaction wheel	Failures and mission impact	The failure of one or more reaction wheels can cause a spacecraft to lose its ability to maintain attitude (orientation) and thus potentially cause a mission failure. Recent studies conclude that these failures can be correlated with space weather effects. These events probably caused failures by inducing electrostatic discharge in the steel ball bearings of Ithaco wheels, compromising the smoothness of the mechanism.
Reaction wheel	Failures and mission impact	Hubble Space Telescope Two servicing missions to the Hubble Space Telescope have replaced a reaction wheel. In February 1997, the Second Servicing Mission (STS-82) replaced one after 'electrical anomalies', rather than any mechanical problem. Study of the returned mechanism provided a rare opportunity to study equipment that had undergone long-term service (seven years) in space, particularly for the effects of vacuum on lubricants. The lubricating compound was found to be in 'excellent condition'. In 2002, during Servicing Mission 3B (STS-109), astronauts from the shuttle Columbia replaced another reaction wheel. Neither of these wheels had failed and Hubble was designed with four redundant wheels, and maintained pointing ability so long as three were functional.
Reaction wheel	Failures and mission impact	Hayabusa In 2004, during the mission of the Hayabusa spacecraft, an X-axis reaction wheel failed. The Y-axis wheel failed in 2005, causing the craft to rely on chemical thrusters to maintain attitude control.
Reaction wheel	Failures and mission impact	Kepler From July 2012 to May 11, 2013, two out of the four reaction wheels in the Kepler telescope failed. This loss severely affected Kepler's ability to maintain a sufficiently precise orientation to continue its original mission. On August 15, 2013, engineers concluded that Kepler's reaction wheels cannot be recovered and that planet-searching using the transit method (measuring changes in star brightness caused by orbiting planets) could not continue. Although the failed reaction wheels still function, they are experiencing friction exceeding acceptable levels, and consequently hindering the ability of the telescope to properly orient itself. The Kepler telescope was returned to its "point rest state", a stable configuration that uses small amounts of thruster fuel to compensate for the failed reaction wheels, while the Kepler team considered alternative uses for Kepler that do not require the extreme accuracy in its orientation needed by the original mission. On May 16, 2014, NASA extended the Kepler mission to a new mission named K2, which uses Kepler differently, but allows it to continue searching for exoplanets. On October 30, 2018, NASA announced the end of the Kepler mission after it was determined that the fuel supply had been exhausted.
Reaction wheel	Failures and mission impact	Dawn The NASA space probe Dawn had excess friction in one reaction wheel in June 2010. It was originally scheduled to depart Vesta and begin its two-and-a-half-year journey to Ceres on August 26, 2012; however, a problem with another of the spacecraft's reaction wheels forced Dawn to briefly delay its departure from Vesta's gravity until September 5, 2012, and it planned to use thruster jets instead of the reaction wheels during the three-year journey to Ceres. The loss of the reaction wheels limited the camera observations on the approach to Ceres.
Reaction wheel	Failures and mission impact	Swift Observatory On the evening of Tuesday, January 18, 2022, a possible failure of one of the Swift Observatory's reaction wheels caused the mission control team to power off the suspected wheel, putting the observatory in safe mode as a precaution. This was the first time a reaction wheel failed on Swift in 17 years. Swift resumed science operations on February 17, 2022.
Leaf power	Leaf power	In the mathematical area of graph theory, a k-leaf power of a tree T is a graph G whose vertices are the leaves of T and whose edges connect pairs of leaves whose distance in T is at most k. That is, G is an induced subgraph of the graph power Tk , induced by the leaves of T. For a graph G constructed in this way, T is called a k-leaf root of G.
Leaf power	Leaf power	A graph is a leaf power if it is a k-leaf power for some k. These graphs have applications in phylogeny, the problem of reconstructing evolutionary trees.
Leaf power	Related classes of graphs	Since powers of strongly chordal graphs are strongly chordal and trees are strongly chordal, it follows that leaf powers are strongly chordal graphs. Actually, leaf powers form a proper subclass of strongly chordal graphs; a graph is a leaf power if and only if it is a fixed tolerance NeST graph and such graphs are a proper subclass of strongly chordal graphs.In Brandstädt et al. (2010) it is shown that interval graphs and the larger class of rooted directed path graphs are leaf powers. The indifference graphs are exactly the leaf powers whose underlying trees are caterpillar trees.
Leaf power	Related classes of graphs	The k-leaf powers for bounded values of k have bounded clique-width, but this is not true of leaf powers with unbounded exponents.
Leaf power	Structure and recognition	A graph is a 3-leaf power if and only if it is a (bull, dart, gem)-free chordal graph. Based on this characterization and similar ones, 3-leaf powers can be recognized in linear time.Characterizations of 4-leaf powers are given by Rautenbach (2006) and Brandstädt, Le & Sritharan (2008), which also enable linear time recognition. Recognition of the 5-leaf and 6-leaf power graphs are also solved in linear time by Chang and Ko (2007) and Ducoffe (2018), respectively. For k ≥ 7 the recognition problem of k-leaf powers was unsolved for a long time, but Lafond (2021) showed that k-leaf powers can be recognized in polynomial time for any fixed k. However, the high dependency on the parameter k makes this algorithm unsuitable for practical use. Also, it has been proved that recognizing k-leaf powers is fixed-parameter tractable when parameterized by k and the degeneracy of the input graph.
In-crowd algorithm	In-crowd algorithm	The in-crowd algorithm is a numerical method for solving basis pursuit denoising quickly; faster than any other algorithm for large, sparse problems. This algorithm is an active set method, which minimizes iteratively sub-problems of the global basis pursuit denoising: min x12‖y−Ax‖22+λ‖x‖1.
In-crowd algorithm	In-crowd algorithm	where y is the observed signal, x is the sparse signal to be recovered, Ax is the expected signal under x , and λ is the regularization parameter trading off signal fidelity and simplicity. The simplicity is here measured using the sparsity of the solution x , measure through its ℓ1 -norm. The active set strategies are very efficient in this context as only few coefficient are expected to be non-zero. Thus, if they can be identified, solving the problem restricted to these coefficients yield the solution. Here, the features are greedily selected based on the absolute value of their gradient at the current estimate.
In-crowd algorithm	In-crowd algorithm	Other active-set methods for the basis pursuit denoising includes BLITZ, where the selection of the active set is performed using the duality gap of the problem, and The Feature Sign Search, where the features are included based on the estimate of their sign.
In-crowd algorithm	Algorithm	It consists of the following: Declare x to be 0, so the unexplained residual r=y Declare the active set I to be the empty set, and Ic to be its complement (the inactive set) Calculate the usefulness uj=\|⟨rAj⟩\| for each component in Ic If on Ic , no uj>λ , terminate Otherwise, add 25 components to I based on their usefulness Solve basis pursuit denoising exactly on I , and throw out any component of I whose value attains exactly 0. This problem is dense, so quadratic programming techniques work very well for this sub problem.
In-crowd algorithm	Algorithm	Update r=y−Ax - n.b. can be computed in the subproblem as all elements outside of I are 0 Go to step 3.Since every time the in-crowd algorithm performs a global search it adds up to L components to the active set, it can be a factor of L faster than the best alternative algorithms when this search is computationally expensive. A theorem guarantees that the global optimum is reached in spite of the many-at-a-time nature of the in-crowd algorithm.
Pulsed inductive thruster	Pulsed inductive thruster	A pulsed inductive thruster (PIT) is a form of ion thruster, used in spacecraft propulsion. It is a plasma propulsion engine using perpendicular electric and magnetic fields to accelerate a propellant with no electrode.
Pulsed inductive thruster	Operation	A nozzle releases a puff of gas which spreads across a flat spiraling induction coil of wire about 1 meter across. A bank of capacitors releases a pulse of high voltage electric current of tens of kilovolts lasting 10 microseconds into the coil, generating a radial magnetic field. This induces a circular electrical field in the gas, ionizing it and causing charged particles (free electrons and ions) to revolve in the opposite direction as the original pulse of current. Because the motion of this induced current flow is perpendicular to the magnetic field, the plasma is accelerated out into space by the Lorentz force at a high exhaust velocity (10 to 100 km/s).
Pulsed inductive thruster	Advantages	Unlike an electrostatic ion thruster which uses an electric field to accelerate only one species (positive ions), a PIT uses the Lorentz body force acting upon all charged particles within a quasi-neutral plasma. Unlike most other ion and plasma thrusters, it also requires no electrodes (which are susceptible to erosion) and its power can be scaled up simply by increasing the number of pulses per second. A 1-megawatt system would pulse 200 times per second.
Pulsed inductive thruster	Advantages	Pulsed inductive thrusters can maintain constant specific impulse and thrust efficiency over a wide range of input power levels by adjusting the pulse rate to maintain a constant discharge energy per pulse. It has demonstrated efficiency greater than 50%.Pulsed inductive thrusters can use a wide range of gases as a propellant, such as water, hydrazine, ammonia, argon, or xenon, among many others. Due to this ability, it has been suggested to use PITs for Martian missions: an orbiter could refuel by scooping CO2 from the atmosphere of Mars, compressing the gas and liquefying it into storage tanks for the return journey or another interplanetary mission, whilst orbiting the planet.
Pulsed inductive thruster	Developments	Early development began with fundamental proof-of-concept studies performed in the mid-1960s. NASA conducts experiments on this device since the early 1980s. PIT Mk V, VI and VII NGST (Northrop Grumman Space Technology), as a contractor for NASA, built several experimental PITs. Research efforts during the first period (1965–1973) were aimed at understanding the structure of an inductive current sheet and evaluating different concepts for propellant injection and preionization. In the second period (1979–1988), the focus shifted more towards developing a true propulsion system and increasing the performance of the base design through incremental design changes, with the build of Mk I and Mk IV prototypes.
Pulsed inductive thruster	Developments	The third period (1991-today) began with the introduction of a new PIT thruster design known as the Mk V. It evolved into the Mk VI, developed to reproduce Mk V single-shot tests, which completely characterize thruster performance. It uses an improved coil of hollow copper tube construction and an improved propellant valve, but is electrically identical to the Mk V, using the same capacitors and switches. The Mk VII (early 2000s) has the same geometry as Mk VI, but is designed for high pulse frequency and long-duration firing with a liquid-cooled coil, longer-life capacitors, and fast, high-power solid-state switches. The goal for Mk VII is to demonstrate up to 50 pulses per second at the rated efficiency and impulse bit at 200 kW of input power in a single thruster. Mk VII design is the base for the most recent NuPIT (Nuclear-electric PIT).The PIT has obtained relatively high performance in the laboratory environment, but it still requires additional advancements in switching technology and energy storage before becoming practical for high-power in-space applications, with the need for a nuclear-based onboard power source.
Pulsed inductive thruster	Developments	FARAD FARAD, which stands for Faraday accelerator with radio-frequency assisted discharge, is a lower-power alternative to the PIT that has the potential for space operation using current technologies.In the PIT, both propellant ionization and acceleration are performed by the HV pulse of current in the induction coil, while FARAD uses a separate inductive RF discharge to preionize the propellant before it is accelerated by the current pulse. This preionization allows FARAD to operate at much lower discharge energies than the PIT (100 joules per pulse vs 4 kilojoules per pulse) and allows for a reduction in the thruster's size.
Scan tool (automotive)	Scan tool (automotive)	An automotive scan tool (scanner) is an electronic tool used to interface with, diagnose and, sometimes, reprogram vehicle control modules.There are many types from just as many manufacturers, one of the most familiar being the Snap-On Inc. "brick", or MT2500/MTG2500. Snap-On, Hella Gutmann Solutions, OTC/SPX, Xtool india, Autel, Launch, Vetronix/Bosch and a number of other companies produce various types of scan tools, from simple code readers to highly capable bi-directional computers with programming capabilities.
Scan tool (automotive)	Scan tool (automotive)	The scan tool is connected to the vehicle's data link connector (DLC) and, depending on the particular tool, may only read out diagnostic trouble codes or DTC's (this would be considered a "code reader") or may have more capabilities. Actual scan tools will display live data stream (inputs and outputs), have bi-directional controls (the ability to make the controllers do things outside of normal operations) and may even be able to calibrate/program modules within certain parameters. However, a typical scan tool does not have the ability to fully reprogram modules because it requires a J-2534 pass-through device and specific software.
Scan tool (automotive)	Scan tool (automotive)	Voltas IT created a new generation diagnostic tool – OBDeleven, the device which easily connects to the car, monitors all systems, and activates new car's features. It supports Audi, Volkswagen, SEAT, Škoda, Lamborghini, and Bentley.OBD 1 vs OBD 2 the vehicle will also dictate what the scan tool is able to display. If the vehicle is equipped with OBD 1 it will have significantly less available data when compared to a vehicle equipped with OBD 2.When a vehicle detects a problem, it generates a DTC code which is a unique code that corresponds to the specific problem detected. The code is usually a combination of letters and numbers.
Scan tool (automotive)	Scan tool (automotive)	DTC codes are read by a diagnostic tool, such as an OBD 2 scanner, which is plugged into the vehicle's diagnostic port. The tool communicates with the vehicle's onboard computer and retrieves the DTC codes. The codes are then interpreted by the mechanic or technician to determine the specific problem with the vehicle.
Systematic Parasitology	Systematic Parasitology	Systematic Parasitology is a monthly peer-reviewed medical journal covering all aspects of the taxonomy and systematics of parasites. It was established in 1979 and is published by Springer Science+Business Media. The editor-in-chief is Aneta Kostadinova (Academy of Sciences of the Czech Republic).
Systematic Parasitology	Abstracting and indexing	The journal is abstracted and indexed in: According to the Journal Citation Reports, the journal has a 2013 impact factor of 1.035.
Space architecture	Space architecture	Space architecture is the theory and practice of designing and building inhabited environments in outer space. This mission statement for space architecture was developed at the World Space Congress in Houston in 2002 by members of the Technical Aerospace Architecture Subcommittee of the American Institute of Aeronautics and Astronautics (AIAA). The architectural approach to spacecraft design addresses the total built environment. It is mainly based on the field of engineering (especially aerospace engineering), but also involves diverse disciplines such as physiology, psychology, and sociology.
Space architecture	Space architecture	Like architecture on Earth, the attempt is to go beyond the component elements and systems and gain a broad understanding of the issues that affect design success. Space architecture borrows from multiple forms of niche architecture to accomplish the task of ensuring human beings can live and work in space. These include the kinds of design elements one finds in “tiny housing, small living apartments/houses, vehicle design, capsule hotels, and more.”Much space architecture work has been in designing concepts for orbital space stations and lunar and Martian exploration ships and surface bases for the world's space agencies, chiefly NASA.
Space architecture	Space architecture	The practice of involving architects in the space program grew out of the Space Race, although its origins can be seen much earlier. The need for their involvement stemmed from the push to extend space mission durations and address the needs of astronauts including but beyond minimum survival needs. Space architecture is currently represented in several institutions. The Sasakawa International Center for Space Architecture (SICSA) is an academic organization with the University of Houston that offers a Master of Science in Space Architecture. SICSA also works design contracts with corporations and space agencies. In Europe, The Vienna University of Technology and the International Space University are involved in space architecture research. The TU Wien offers an EMBA in Space Architecture. The International Conference on Environmental Systems (ICES) meets annually to present sessions on human spaceflight and space human factors. Within the American Institute of Aeronautics and Astronautics (AIAA), the Space Architecture Technical Committee (SATC) has been formed. Despite the historical pattern of large government-led space projects and university-level conceptual design, the advent of space tourism threatens to shift the outlook for space architecture work.
Space architecture	Etymology	The word space in space architecture is referring to the outer space definition, which is from English outer and space. Outer can be defined as "situated on or toward the outside; external; exterior" and originated around 1350–1400 in Middle English. Space is "an area, extent, expanse, lapse of time," the aphetic of Old French espace dating to 1300. Espace is from Latin spatium, "room, area, distance, stretch of time," and is of uncertain origin. In space architecture, speaking of outer space usually means the region of the universe outside Earth's atmosphere, as opposed to outside the atmospheres of all terrestrial bodies. This allows the term to include such domains as the lunar and Martian surfaces.
Space architecture	Etymology	Architecture, the concatenation of architect and -ure, dates to 1563, coming from Middle French architecte. This term is of Latin origin, formerly architectus, which came from Greek arkhitekton. Arkitekton means "master builder" and is from the combination of arkhi- "chief" and tekton "builder". The human experience is central to architecture – the primary difference between space architecture and spacecraft engineering.

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