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61,482,208 | https://en.wikipedia.org/wiki/C17H17N3O2 | {{DISPLAYTITLE:C17H17N3O2}}
The molecular formula C17H17N3O2 (molar mass: 295.336 g/mol, exact mass: 295.1321 u) may refer to:
Divaplon (RU-32698)
GYKI-52895
Molecular formulas | C17H17N3O2 | [
"Physics",
"Chemistry"
] | 75 | [
"Molecules",
"Set index articles on molecular formulas",
"Isomerism",
"Molecular formulas",
"Matter"
] |
63,671,402 | https://en.wikipedia.org/wiki/C/2020%20F8%20%28SWAN%29 | C/2020 F8 (SWAN), or Comet SWAN, is an Oort cloud comet that was discovered in images taken by the Solar Wind Anisotropies (SWAN) camera on March 25, 2020, aboard the Solar and Heliospheric Observatory (SOHO) spacecraft. In the glare of twilight, Comet SWAN is difficult to find with 50mm binoculars even though it is still near the theoretical range of naked eye visibility. The comet has dimmed since May 3. As of perihelion, the comet is very diffuse, does not have a visible nucleus and is not a comet that will be noticed by inexperienced observers. It is likely that the comet disintegrated.
Observing
On April 28, 2020 it had an apparent magnitude of 7 and was too diffuse to be visible to the naked eye even from a dark site. The comet was also hidden by the glare of twilight, zodiacal light and atmospheric extinction. It was originally best seen from the Southern Hemisphere. It was expected to possibly reach 3rd magnitude in May, but instead hovered closer to magnitude 6. In either case it was near the glare of twilight, which made it appear significantly fainter. On May 2, the comet had reached a magnitude of 4.7 and had been detected with naked eye, the tail had a visual length of one degree and could be traced photographically for 6-8 degrees. After that the comet faded, probably as the nucleus of the comet fragmented. It passed through the celestial equator on 7 May, then it headed northward and it was near the 2nd magnitude star Algol on 20 May. It passed its perihelion on May 27, 2020.
Orbit
The Minor Planet Center initially listed the orbit as bound with . With a short 18-day observation arc JPL listed the comet as hyperbolic with an eccentricity of , but a longer observation arc was needed to refine the uncertainties and either confirm its hyperbolic trajectory, or determine its orbital period of thousands or millions of years. With a 40-day observation arc it was possible to determine that it came from the Oort cloud on a Hyperbolic trajectory and that the outbound orbit will last ~11,000 years.
On May 12, 2020, the comet passed about from Earth. On May 27, 2020 the comet came to perihelion from the Sun.
Gallery
References
External links
C/2020 F8 (SWAN) – Seiichi Yoshida
C/2020 F8 (SWAN) – JPL
C/2020 F8 Swan on June 1 (without a defined nucleus) – Michael Jäger
C/2020 F8 (SWAN) – AiM-Project
Astronomical objects discovered in 2020
Comets in 2020
Non-periodic comets
Destroyed comets
Oort cloud | C/2020 F8 (SWAN) | [
"Astronomy"
] | 552 | [
"Astronomical hypotheses",
"Oort cloud"
] |
63,672,907 | https://en.wikipedia.org/wiki/Christophe%20Fraser | Christophe Fraser is a professor of Infectious Disease Epidemiology in the Big Data Institute, part of the Nuffield Department of Medicine at the University of Oxford.
Fraser's PhD and initial postdoctoral research were in theoretical particle physics. He converted to infectious disease epidemiology in 1998, based first at the University of Oxford then at Imperial College London, where he became Chair of Theoretical Epidemiology and served as deputy director of the MRC Centre for Outbreak Analysis and Modelling.
He returned to the University of Oxford in 2016 as Senior Group Leader in Pathogen Dynamics at the Big Data Institute.
In 2022 he was appointed Moh Family Foundation Professor of Infectious Disease Epidemiology as part of the University of Oxford's newly created Pandemic Sciences Institute.
Research on HIV
Fraser and colleagues were among the first to hypothesise that the large variability in virulence observed between individuals living with HIV could be partly due to genetic variation in the virus.
In other words they hypothesised that virulence, considered as a phenotype of the virus, has appreciable heritability.
They and others later provided evidence for this.
Fraser was principal investigator of the BEEHIVE project to investigate the mechanism of this heritability, which discovered the 'VB variant': a highly virulent strain within the B subtype of HIV found in 107 individuals living with HIV in the Netherlands. UNAIDS stated that the discovery "provides evidence of urgency to halt the pandemic and reach all with testing and treatment".
Research on the COVID-19 pandemic
In March 2020 Fraser and his research group published epidemiological modelling supporting 'digital contact tracing' using COVID-19 apps to reduce the spread of SARS-CoV-2.
Fraser provided advice to the British government and more broadly about implementing such apps, including designing a risk evaluation algorithm with Anthony Finkelstein and others.
Fraser's team developed the OpenABM-Covid-19 agent-based model, used by the NHS to model the pandemic, winning the 2021 Analysis in Government award for Innovative methods.
Research on other outbreaks
Fraser worked on
the 2002–2004 SARS outbreak,
the 2009 swine flu pandemic,
the 2012 MERS outbreak
and the Western African Ebola virus epidemic.
Methodological research
Fraser's publications include "Factors that make an infectious disease outbreak controllable", 2004, which argued that in addition to the basic reproduction number a second key parameter of an infectious disease is the proportion of transmission that occurs before the onset of symptoms.
This proportion being large for SARS-CoV-2 was a key difficulty in infection control for the COVID-19 pandemic.
Fraser's 2007 analysis "Estimating Individual and Household Reproduction Numbers in an Emerging Epidemic" first defined an estimator for the instantaneous (time-varying) reproduction number that was subsequently widely used. The definition was obtained by inverting the standard relationship between the reproduction number, the generation time distribution and the parameter of the Malthusian growth model that is implied by the renewal equation for epidemic dynamics (or the Euler-Lotka equation as it is known in demography; the two are equivalent due to actual births being analogous to infectious disease transmissions as 'epidemiological births', giving rise to a new infected individual).
References
Living people
Academics of the University of Oxford
Academics of Imperial College London
Alumni of the University of Edinburgh
British epidemiologists
Mathematical and theoretical biology
COVID-19 pandemic in England
1973 births | Christophe Fraser | [
"Mathematics"
] | 724 | [
"Applied mathematics",
"Mathematical and theoretical biology"
] |
63,673,009 | https://en.wikipedia.org/wiki/Big%20Data%20Institute | The Big Data Institute (BDI), part of the Li Ka Shing Centre for Health Information and Discovery, is an interdisciplinary research institute at the University of Oxford. The institute brings together researchers from both the Nuffield Department of Population Health and the Nuffield Department of Medicine. The BDI building is on the Old Road Campus in Headington, east Oxford, England.
Academics from the BDI are advising the British government about a mobile phone app to track the COVID-19 pandemic in the United Kingdom.
References
External links
BDI website
Big data
COVID-19 pandemic in England
Departments of the University of Oxford
Medical research institutes in the United Kingdom
Organizations with year of establishment missing
Population genetics organizations
Research institutes of the University of Oxford | Big Data Institute | [
"Technology"
] | 155 | [
"Data",
"Big data"
] |
63,674,823 | https://en.wikipedia.org/wiki/Non-pharmaceutical%20intervention%20%28epidemiology%29 | In epidemiology, a non-pharmaceutical intervention (NPI) is any method used to reduce the spread of an epidemic disease without requiring pharmaceutical drug treatments. Examples of non-pharmaceutical interventions that reduce the spread of infectious diseases include wearing a face mask and staying away from sick people.
The US Centers for Disease Control and Prevention (CDC) points to personal, community, and environmental interventions. NPIs have been recommended for pandemic influenza at both local and global levels and studied at large scale during the 2009 swine flu pandemic and the COVID-19 pandemic. NPIs are typically used in the period between the emergence of an epidemic disease and the deployment of an effective vaccine.
Types
Choosing to stay home to prevent the spread of symptoms of a potential sickness, covering coughs and sneezes, and washing one's hands regularly, are all examples of non-pharmaceutical interventions. Another example is when administrators of schools, workplaces, community areas, etc., take proper preventive actions and remind people to take precautions when need be in order to avoid the spread of disease. Most NPIs are simple, requiring little effort to put into practice, and, if implemented correctly, have the potential to save lives.
Personal protective measures
Hand hygiene
Respiratory etiquette
Face masks
Environmental measures
Surface and object cleaning
Germs can survive outside the body on hard surfaces for periods ranging from hours to weeks, depending on the virus and environmental conditions. The disinfection of high-touch surfaces with substances such as bleach or alcohol kills germs, preventing indirect contact transmission. Dirty surfaces should be washed before the use of disinfectant.
Ultraviolet lights
Ultraviolet (UV) light can be used to destroy micro-organisms that exist in the environment. The installation of UV light fixtures can be costly and time consuming; it is unlikely that they could be used at the outbreak of an epidemic. There are possible health concerns involving UV light, as it may cause cancer and eye problems. The WHO does not recommend its use.
Increased ventilation
Increased ventilation of a room through opening a window or through mechanized ventilation systems may reduce transmission within the room. Although opening a window may introduce allergens and air pollution, or, in some climates, cold air, it is overall a cheap and effective type of intervention, and its advantages probably outweigh its disadvantages.
Modifying humidity
Viruses such as influenza and coronavirus thrive in cold, dry environments, and increasing the humidity of a room may reduce their transmission. Higher humidity, however, may cause mold and mildew, which may in turn cause respiratory problems. Humidifiers are also expensive and will probably be in short supply at the start of an epidemic.
Social distancing measures
Contact tracing
Isolation of sick individuals
Quarantine of exposed individuals
Quarantine involves the voluntary or imposed confinement of potentially non-ill persons who have been exposed to an illness, regardless of whether they have contracted it. Quarantine will often happen at home, but it may happen elsewhere, such as aboard ships (maritime quarantine) or airlines (onboard quarantine). Like isolation of sick individuals, forced quarantine of exposed individuals brings with it ethical concerns, although in this case the concerns may be greater; quarantine involves restricting the movement of those who may otherwise be well, and in some cases may even cause them greater risk if they are quarantining with the sick person to whom they were exposed, such as a sick family member or roommate with whom they live. Like isolation, quarantine brings with it financial risk, because of work absenteeism.
School measures and closures
Measures taken involving schools range from making changes to operations within schools to complete school closures. Lesser measures may involve reducing the density of students, such as by distancing desks, cancelling activities, reducing class sizes, or staggering class schedules. Sick students may be isolated from the greater student body, such as by having them stay at home or otherwise segregate them from other students.
More drastic measures include class dismissal, in which classes are cancelled but the school stays open to provide childcare to some children, and complete school closure. Both measures may be either reactive or proactive: In a reactive case, the measure takes place after an outbreak has occurred in the school; in a proactive case, the measure takes place in order to prevent spread within the community.
Closures of schools may affect the families of affected children, especially low-income families. Parents may be forced to miss work to care for their children, affecting financial stability; children may also miss out on free school meals, causing nutritional concerns. Long absences from schools because of closures can also have negative effects on students' education.
However, in the months following the onset of the COVID-19 pandemic, instead of closures, remote learning was turned to as an intervention against infection by SARS-CoV-2 in the days before vaccines.
Workplace measures and closures
Measures taken in the workplace include: remote work; paid leave; staggering shifts such that arrival, exit, and break times are different for each employee; reduced contact; and extended weekends.
Workplace closure is a more drastic measure. The financial effect of workplace closure on both the individual and the economy can be severe. When remote work is not possible, such as in essential services, businesses may not be able to comply with guidelines. In one simulation study school closure coupled with 50% absenteeism in the workplace would have had the highest financial impact of all the scenarios studied, although some studies have found that the combination would be effective in reducing both the attack rate and the height of an epidemic.
One benefit of workplace closure is that when used in conjunction with school closures they avoid the need for parents to make childcare arrangements for children who are staying away from school.
The WHO recommends workplace closure in the case of extraordinarily severe epidemics and pandemics.
Avoiding crowding
Avoiding crowding may involve: avoiding crowded areas such as shopping centres and transportation hubs; closing public spaces and banning large gatherings, such as sports events or religious activities; or setting a limit on small gatherings, such as limiting them to no more than a few people. There are negative consequences to the banning of gatherings; banning cultural or religious activities, for example, may prevent access to support in a time of crisis. Gatherings also allow sharing of information, which can provide comfort and reduce fear.
The WHO recommends this intervention in moderate and severe epidemics and pandemics.
Travel-related measures
Travel advice
Travel advice involves notifying potential travelers that they may be entering a zone that is affected by a disease outbreak. It allows informed decisions to be made before travel, and it increases awareness when the traveler is in the destination country. Public awareness campaigns have been used in the past for areas affected by infectious diseases such as dengue, malaria, Middle East respiratory syndrome, and H1N1 influenza. Although such awareness campaigns may reduce exposure among those traveling abroad, they may cause economic impact, owing to reduced travel in countries about which the advice has been issued. Overall, this intervention type is considered both feasible and acceptable.
Entry and exit screening
Entry and exit screening involves screening travelers at ports of entry for symptoms of illness. Measures include: health declarations, in which travelers make a declaration that they have not recently had symptoms of illness; visual inspections of the traveler; and the use of non-contact thermography, in which a device such as a thermographic camera is used to measure the traveler's body temperature, in order to determine if they have a fever. Such a method may be circumvented by the traveler through the use of antipyretics before travel in order to reduce fever. More intensive measures such as molecular diagnostics and point-of-care rapid antigen detection tests may also be used, but they carry a high resource cost and may not be applicable to a large number of travelers. A substantial number of resources may be needed in order to train staff and acquire equipment.
Although there is probably no harm to the traveler by the use of this type of intervention, a limitation of it is that travelers may be asymptomatic on arrival and symptoms may not show until several days after entry, at which point they may have already exposed others to their illness. There are also ethical concerns involving invading the privacy of the traveler. Screening is considered by the WHO to be both acceptable and feasible, though they did not recommend its use in the case of influenza outbreak due to its inefficacy in identifying asymptomatic individuals.
Internal travel restrictions
Travel within a country may be restricted in order to delay the spread of disease. Restriction of travel within a country is likely to slow the spread of disease, but not prevent it entirely. Its use would be most effective at the start of a localized and extraordinarily severe pandemic for only a short period of time. It would only be effective if the measures were strict: while a 90% restriction was projected to delay spread by one or two weeks, a 75% restriction saw no effect. An analysis of the spread of influenza in America following complete airline closures due to the September 11 attacks saw reduced spread by 13 days compared with previous years.
Restricting travel brings both ethical, and in many countries, legal challenges. Freedom of movement is considered in many places to be a human right, and its restriction may have an adverse effect, particularly among vulnerable populations, such as migrant workers and those traveling to seek medical attention. Although 37% of the Member States of the WHO included internal travel restrictions as part of their pandemic preparedness plan as of 2019, some of those countries may face legal challenges in implementing them, because of their own laws. Such restrictions may also bring economic effects because of disruption in the supply chain.
Border closure
Border closure is a measure that involves complete or severe restriction of travel across borders. This had a beneficial effect in delaying the spread of cases of influenza during the 1918 influenza pandemic, and was predicted to delay epidemic spread between Hong Kong and mainland China by 3.5 weeks. While border closure is expected to slow the spread of infection, it is not expected to reduce the duration of an epidemic. Strict border closure in island nations could be effective, although supply chain problems may cause adverse disruptions.
Supply chain problems due to border closure are likely to cause disruption of essential goods, such as food and medications, as well as serious economic effects. They may have adverse effects on the daily lives of individuals. Border closure also has serious ethical implications, because, like internal travel restrictions, it involves restricting the movements of individuals. It should only be used as a voluntary measure to the maximum extent possible. There may also be stigmatization of individuals from affected areas.
Border closure would be most feasible at the very start of a pandemic. The WHO recommended it only in extraordinary circumstances, and asked that they be notified by any nation implementing it.
1918 influenza pandemic
Non-pharmaceutical interventions were widely adopted during the 1918 flu outbreak – most famously, the radical quarantine of Gunnison, Colorado resulted in sparing the town the worst of the earlier waves of the pandemic. Interventions used included the wearing of face masks, isolation, quarantine, personal hygiene, use of disinfectants, and limits on public gatherings. At the time, the science behind NPIs was new, and was not applied consistently in every area. Retroactive studies on the outbreak have shown that the measures were effective in mitigating the spread of the infection.
The use of non-pharmaceutical interventions during the 1918 flu pandemic also gave rise to new societal concerns. There was a growing awareness of "overreacting" and "under-reacting" among U.S. public health authorities, and these opposing perspectives often added to the uncertainties inherent in the epidemic. Likewise, public perceptions varied with respect to adherence to public health guidelines, giving rise to terms such as "mask slackers" and "careless consumptives."
COVID-19
COVID-19 is a disease caused by the SARS-CoV-2 virus, which spread from China, creating a pandemic. Several COVID-19 vaccines are now being used, 6.54 billion doses having been administered worldwide as of 12 October 2021.
In the early stages of the COVID-19 pandemic, before vaccines had been developed, NPIs were key in mitigating infections and reducing COVID-19-related mortality. Some NPIs remained in place or were reinstituted for a time after vaccine rollout. One report identified over 500 specific NPIs for controlling transmission and spread of the SARS-CoV-2 virus; most of these have been tried in practice. Evidence suggests that highly effective strategies include closing schools and universities, banning large gatherings, and wearing face masks.
Engineering controls
NPIs are still key to mitigating infections. NPIs, which include engineering controls under the Hierarchy of hazard controls, do not require compliance with PPE mandates, or require administrative changes, like lockdowns, to prevent the spread of disease among the general public.
Proposed controls
See also
Flatten the curve
References
Further reading
External links
Nonpharmaceutical Interventions on Centers for Disease Control and Prevention
Epidemiology
Centers for Disease Control and Prevention
Public health
Medical hygiene | Non-pharmaceutical intervention (epidemiology) | [
"Environmental_science"
] | 2,720 | [
"Epidemiology",
"Environmental social science"
] |
63,675,213 | https://en.wikipedia.org/wiki/Atomic%20manipulation | Atomic manipulation is the process of moving single atoms on a substrate using Scanning Tunneling Microscope (STM). The atomic manipulation is a surface science technique usually used to create artificial objects on the substrate made out of atoms and to study electronic behaviour of matter. These objects do not occur in nature and therefore need to be created artificially. The first demonstration of atomic manipulation was done by IBM scientists in 1989, when they created IBM in atoms.
Vertical manipulation
Vertical manipulation is a process of transferring an atom from substrate to STM tip, repositioning the STM tip and transferring the atom back on a desired position. Transferring an atom from substrate to STM tip is done by placing the tip above the atom in a constant current mode, turning off the feedback loop and applying high bias for a few seconds. In some cases it is also required to slowly approach the tip while applying high bias. Sudden spikes or drops in current during this process correspond to either transfer or to the atom being pushed away from the given spot. As such, there is always some level of randomness in this process. Transferring an atom from STM tip to substrate is done the same way but by applying opposite bias.
Lateral manipulation
Lateral manipulation means moving an adsorbate on the surface by making a temporary chemical or physical bond between the STM tip and the adsorbate. A typical lateral manipulation sequence begins by positioning the tip close to the adsorbate, bringing the tip close to the surface by increasing the tunneling current setpoint, moving the tip along a desired route and finally retracting the tip to normal scanning height. Lateral manipulation is typically applied to strongly bound adsorbates, such as metal adatoms on metal surfaces. The probability that the surface adsorbate moves the same distance traveled by the tip is strongly dependent on the tip conditions.
Depending on the tip apex and the surface/adsorbate system, the lateral motion can occur by pushing, pulling or sliding of the adsorbate. These modes result in distinct tunneling current signals during the lateral motion. For example, periodic steps in the tunneling current indicate that the adsorbate is “jumping” between adsorption sites while following the tip: this means the tip pushes or pulls the adsorbate.
Notable experiments
Several groups have applied atomic manipulation techniques for artistic purposes to demonstrate control over the adatom positions. These include various institutional logos and a movie called “A Boy and His Atom” composed of individual STM scans by IBM researchers.
Several notable condensed matter physics experiments have been realized with atomic manipulation techniques. These include the demonstration of electron confinement in so-called quantum corrals by Michael F. Crommie et al., and the subsequent Quantum mirage experiment, where the Kondo signature of an adatom was reflected from one focus to another in an elliptical quantum corral.
Atomic manipulation has also sparked interest as a computation platform. Andreas J. Heinrich et al. built logic gates out of molecular cascades of CO adsorbates, and Kalff et al. demonstrated a rewritable kilobyte memory made of individual atoms.
Recent experiments on artificial lattice structures have utilized atomic manipulation techniques to study the electronic properties of Lieb lattices, artificial graphene and Sierpiński triangles.
References
Surface science
Nanotechnology | Atomic manipulation | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 669 | [
"Nanotechnology",
"Condensed matter physics",
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"Materials science"
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63,676,220 | https://en.wikipedia.org/wiki/Okubo%E2%80%93Weiss%20parameter | In fluid mechanics, the Okubo–Weiss parameter, (normally given by "W") is a measure of the relative importance of deformation and rotation at a given point. It is calculated as the sum of the squares of normal and shear strain minus the relative vorticity. This is widely applicable in fluid properties particularly in identifying and describing oceanic eddies.
For a horizontally non-divergent flow in the ocean, the parameter is given by:
where:
is the normal strain.
is the shear strain.
is the relative vorticity.
References
Okubo, A., 1970: Horizontal dispersion of floatable particles in the vicinity of velocity singularities such as convergences. Deep-Sea Res., 17, 445–454
Weiss, J., 1991: The dynamics of enstrophy transfer in two-dimensional hydrodynamics. PhysicaD, 48, 273–294
Fluid dynamics
Continuum mechanics | Okubo–Weiss parameter | [
"Physics",
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"Engineering"
] | 193 | [
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"Classical mechanics",
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"Fluid dynamics stubs",
"Fluid dynamics"
] |
63,676,308 | https://en.wikipedia.org/wiki/PABPC5 | Poly(A) binding protein cytoplasmic 5 is a protein that in humans is encoded by the PABPC5 gene.
Function
This gene encodes a poly(A)-binding protein that binds to the polyA tail found at the 3' end of most eukaryotic mRNAs. It is thought to play a role in the regulation of mRNA metabolic processes in the cytoplasm. This gene is located in a gene-poor region within the X-specific 13d-sY43 subinterval of the chromosome Xq21.3/Yp11.2 homology block. It is located close to translocation breakpoints associated with premature ovarian failure, and is therefore a potential candidate gene for this disorder. [provided by RefSeq, May 2010].
References
Further reading
Proteins | PABPC5 | [
"Chemistry"
] | 171 | [
"Biomolecules by chemical classification",
"Proteins",
"Molecular biology"
] |
63,677,270 | https://en.wikipedia.org/wiki/Spoof%20surface%20plasmon | Spoof surface plasmons, also known as spoof surface plasmon polaritons and designer surface plasmons, are surface electromagnetic waves in microwave and terahertz regimes that propagate along planar interfaces with sign-changing permittivities. Spoof surface plasmons are a type of surface plasmon polariton, which ordinarily propagate along metal and dielectric interfaces in infrared and visible frequencies. Since surface plasmon polaritons cannot exist naturally in microwave and terahertz frequencies due to dispersion properties of metals, spoof surface plasmons necessitate the use of artificially-engineered metamaterials.
Spoof surface plasmons share the natural properties of surface plasmon polaritons, such as dispersion characteristics and subwavelength field confinement. They were first theorized by John Pendry et al.
Theory
Surface plasmon polaritons (SPP) result from the coupling of delocalized electron oscillations ("surface plasmon") to electromagnetic waves ("polariton"). SPPs propagate along the interface between a positive- and a negative-permittivity material. These waves decay perpendicularly from the interface ("evanescent field"). For a plasmonic medium that is stratified along the z-direction in Cartesian coordinates, dispersion relation for SPPs can be obtained from solving Maxwell's equations:
where
is the wave vector that is parallel to the interface. It is in the direction of propagation.
is the angular frequency.
is the speed of light.
and are the relative permittivies for metal and the dielectric.
Per this relation, SPPs have shorter wavelengths than light in free space for a frequency band below surface plasmon frequency; this property, as well as subwavelength confinement, enables new applications in subwavelength optics and systems beyond the diffraction-limit. Nevertheless, for lower frequency bands such as microwave and terahertz, surface plasmon polariton modes are not supported; metals function approximately as perfect electrical conductors with imaginary dielectric functions in this regime. Per the effective medium approach, metal surfaces with subwavelength structural elements can mimic the plasma behaviour, resulting in artificial surface plasmon polariton excitations with similar dispersion behaviour.
For the canonical case of a metamaterial medium that is formed by thin metallic wires on a periodic square lattice, the effective relative permittivity can be represented by the Drude model formula:
where
is the effective plasma frequency of the medium.
is the vacuum permittivity.
is the lattice period.
is the radius of the constitutive wires.
is the electrical conductivity of the metal.
Methods and applications
The use of subwavelength structures to induce low-frequency plasmonic excitations was first theorized by John Pendry et al. in 1996; Pendry proposed that a periodic lattice of thin metallic wires with a radius of 1 μm could be used to support surface-bound modes, with a plasma cut-off frequency of 8.2 GHz. In 2004, Pendry et al. extended the approach to metal surfaces that are perforated by holes, terming the artificial SPP excitations as "spoof surface plasmons."
In 2006, terahertz pulse propagation in planar metallic structures with holes were shown via FDTD simulations. Martin-Cano et al. has realized the spatial and temporal modulation of guided terahertz modes via metallic parallelepiped structures, which they termed as "domino plasmons." Designer spoof plasmonic structures were also tailored to improve the performance of terahertz quantum cascade lasers in 2010.
Spoof surface plasmons were proposed as a possible solution for decreasing the crosstalk in microwave integrated circuits, transmission lines and waveguides. In 2013, Ma et al. demonstrated a matched conversion from coplanar waveguide with a characteristic impedance of 50Ω to a spoof-plasmonic structure. In 2014, integration of commercial low-noise amplifier with spoof plasmonic structures was realized; the system reportedly worked from 6 to 20 GHz with a gain around 20 dB. Kianinejad et al. also reported the design of a slow-wave spoof-plasmonic transmission line; conversion from quasi-TEM microstrip modes to TM spoof plasmon modes were also demonstrated.
Khanikaev et al. reported nonreciprocal spoof surface plasmon modes in structured conductor embedded in an asymmetric magneto-optical medium, which results in one-way transmission. Pan et al. observed the rejection of certain spoof plasmon modes with an introduction of electrically resonant metamaterial particles to the spoof plasmonic strip. Localized spoof surface plasmons were also demonstrated for metallic disks in microwave frequencies.
See also
Photonic crystal
Plasmonic metamaterial
Split-ring resonator
Superlens
Terahertz metamaterial
References
Further reading
Plasmonics
Metamaterials
Microwave technology
Terahertz technology
Microtechnology
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63,677,789 | https://en.wikipedia.org/wiki/Jenner%20Institute | The Jenner Institute is a research institute on the Old Road Campus in Headington, east Oxford, England. It was formed in November 2005 through a partnership between the University of Oxford and the UK Institute for Animal Health. It is associated with the Nuffield Department of Medicine, in the Medical Sciences Division of Oxford University. The institute receives charitable support from the Jenner Vaccine Foundation.
The institute is led by Prof. Adrian Hill. The institute develops vaccines and carries out clinical trials for diseases including malaria, tuberculosis (vaccine MVA85A), ebola, and MERS-Coronavirus.
In 2020, the institute successfully developed the Oxford–AstraZeneca COVID-19 vaccine, in a project backed by private companies including Oxford Sciences Innovation, Google Ventures, and Sequoia Capital, among others. When developed, the UK government backed trials, purchased 100million doses, and encouraged Oxford to work with AstraZeneca, a company based in Europe, instead of Merck & Co., a US-based company; while the US gave of government funding in return for 300 million doses. It collaborated with Italy's Advent Srl (part of the IRBM Group) on the development and Germany's Merck Group on the manufacture of the COVID-19 vaccine. Vaccinologist Dame Sarah Gilbert was one of the leading scientists involved in the development.
The institute is named after the English physician and immunization pioneer Edward Jenner (1749–1823), who was a major contributor to the development of the smallpox vaccine.
History
Previously, the Edward Jenner Institute for Vaccine Research was an independent research institute named after Edward Jenner, the inventor of vaccination. It was co-located with the Compton Laboratory of the Institute for Animal Health on a campus in the village of Compton in Berkshire. After occupying temporary laboratory space at the Institute for Animal Health from 1996, the institute moved to a newly completed laboratory building in 1998. Funding of the institute continued until October 2005, when it was relaunched replacing the four founding funding partners (GlaxoSmithKline, the Medical Research Council, the Biotechnology and Biological Sciences Research Council and the Department of Health) with the University of Oxford and the Institute for Animal Health.
References
2005 establishments in England
Research institutes established in 2005
Research institutes in Oxford
Departments of the University of Oxford
Research institutes of the University of Oxford
Medical research institutes in the United Kingdom
Vaccination-related organizations
COVID-19 pandemic in England | Jenner Institute | [
"Biology"
] | 505 | [
"Vaccination-related organizations",
"Vaccination"
] |
63,678,076 | https://en.wikipedia.org/wiki/Helen%20Branswell | Helen Branswell is a Canadian infectious diseases and global health reporter at Stat News. Branswell spent fifteen years as a medical reporter at The Canadian Press, where she led coverage of the Ebola, Zika, SARS and swine flu pandemics. She joined Stat News at its founding 2015, leading the website's coverage of the ongoing COVID-19 pandemic.
Early life and education
Branswell is from Canada and has family in Ottawa. In 1978, Branswell received a B.A. in English literature the St. Thomas University in New Brunswick, Canada. When asked how she wound up in journalism she replied: "I fell into journalism, I was not somebody who had worked at a high school newspaper or college newspaper or anything. I just didn’t know what to do after getting a Bachelor of Arts degree in English Literature. And somebody said, “What can you do?” And I said, “I think I can write.” And so, I started freelancing for the local paper in the small town I lived in at the time in Eastern Canada at $15 a story. And the rest is history, but with a lot of moves and a lot of different opportunities along the way."
Career
Branswell joined The Canadian Press in 1986, where she served as London correspondent for five years. She started out in general news, working as a political reporter and foreign correspondent. She switched to medical reporting in 2000, and became well known for her coverage of global health outbreaks, starting with the first 2002–2004 SARS outbreak where she reported "on the only real outbreak outside of Asia." Branswell led the coverage of the Severe Acute Respiratory Syndrome (SARS), Ebola, Avian influenza, Zika, Middle East respiratory syndrome and swine flu pandemics. In 2004 Branswell was a Knight Fellow at the Centers for Disease Control.
In 2011 Branswell was a Nieman Fellow at Harvard University. Here she concentrated on Polio eradication, with a focus on how India is fighting the spread of poliovirus. During an interview with the Nieman Foundation for Journalism, Branswell provided an overview of her experience on reporting during pandemics. This report included advice on which stories to cover and which not cover, how to identify reliable sources and how to prepare for interviews with researchers. The Canadian Press did not have a large budget and Branswell wrote most of her articles from her office or home.
In 2015 Branswell left The Canadian Press to join Stat News, a health news website which had launched that year. Branswell is a popular science communicator; she was often recommended as an important health journalist to follow on Twitter during the COVID-19 pandemic. She was selected as a Harvard Medical School media fellow in 2019.
Coverage of the COVID-19 pandemic
Branswell led the Stat News reporting on the coronavirus pandemic. She first started sharing concerns about the emerging outbreak on December 31, 2019. Branswell had read a ProMED-mail posting that described an unexplained pneumonia in Wuhan, which concerned her because of its similarities to SARS. Two days later, in early January 2020, Branswell tweeted, “Not liking the look of this”. By January 4 Branswell had written her first article on SARS-CoV-2 for Stat News, predicting that it could be "a new coronavirus".
Branswell used her Twitter feed to discuss recent developments as well as debunking misinformation. She remarked that, for the scientific community, this virus was different to other pandemics, because the rise of preprint serves meant that journalists and the public had access to data and research much faster than before. She covered the development of a COVID-19 vaccine, interviewing the Head of Vaccine research at Sanofi, who estimated that it would take three years before the vaccine was widely available. Sanofi have experience in the development of a SARS vaccination, as well as the ability to do large-scale manufacture, which Branswell believes is crucial to produce vaccinations for people all over the world. She questioned why Robert R. Redfield, director of the Centers for Disease Control, was so silent throughout the outbreak, whereas they provided regular briefings during the 2009 swine flu pandemic.
Fellowships and awards
1992: University of Toronto, Southam journalism fellow
2004: Centers for Disease Control and Prevention, Knight Fellow
2011: Harvard University, Nieman Fellow: Nieman Global Health Fellowship
2020: George Polk Journalism Award for Public Service. In the announcement of the award, the reporting for which she won the award was described as follows: "Branswell tracked the spread of the virus in 161 articles — more than three a week —[articles] that were almost uniformly timely and astute."
2021: Council for the Advancement of Science Writing, Victor Cohn Prize for Excellence in Medical Science Reporting, shared with Amy Maxmen
References
External links
Helen Branswell at STAT
Living people
Year of birth missing (living people)
Women science writers
Canadian science writers
St. Thomas University (New Brunswick) alumni
20th-century Canadian journalists
20th-century Canadian women writers
21st-century Canadian journalists
21st-century Canadian women writers
Canadian science journalists
20th-century Canadian women journalists
21st-century Canadian women journalists | Helen Branswell | [
"Technology"
] | 1,089 | [
"Women science writers",
"Women in science and technology"
] |
63,678,227 | https://en.wikipedia.org/wiki/Sarah%20Elizabeth%20Whitin | Sarah Elizabeth Whitin (born April 18, 1836, died Dec 26, 1917) was sole benefactor of the Whitin Observatory, which she had built on the campus of Wellesley College near Boston.
Biography
She was born Sarah Elizabeth Pratt, daughter of a physician in Hopkinton, Mass. In her childhood, Sarah Elizabeth was fascinated by the stars and on dark nights, would spread out a blanket in the open and, armed with an atlas, would lie in the dark with friends and identify constellations.
On January 20, 1875, when she was almost 39 years old, Sarah became the second wife of the industrialist John Crane Whitin (1807–1882), owner of the Whitin Machine Works in Whitinsville, Massachusetts. John was almost 30 years her senior and died only seven years later. After his passing, Sarah was "left with large means" and traveled extensively.
Trustee
Sarah Elizabeth Whitin was elected to the Wellesley College Board of Trustees in 1896 and immediately took a keen interest in campus activities, especially the study of astronomy. In 1896, she became engaged in conversation with the college's first professor of physics and astronomy, Sarah Frances Whiting (they had very similar names but were not related). At the time, the college only had a portable telescope measuring 4 inches, which could be put on a porch roof of College Hall for celestial observations.
At a campus gathering, Professor Whiting mentioned to Mrs. Whitin that there was a 12-inch refracting telescope still in use in the Olmstead Observatory "which had suddenly become available at a bargain price." Professor Whiting had used the telescope when she taught in Brooklyn, N.Y. and encouraged its purchase for use at a new Wellesley observatory.
In response to Professor Whiting's suggestions for a new observatory, Whitin wrote "You need not feel that you have made extravagant suggestions. It is only the carrying out of my own ideas as they become broader... My ideas are now way ahead of the little observatory or of my bank account, else it would be far better than it will be!"
Observatory
As told in Wellesley College 1875–1975: A Century of Women, the telescope was bought in 1899.In the fall of 1898 [Whitin] proposed to give, and the Trustees voted to accept with gratitude, "a [12-inch] telescope and a simple building to house the instrument." Then at a Trustees meeting the following May, "Mrs. Whitin stated that she now proposes to construct the Observatory of white marble in place of brick." When it was formally opened on October 8, 1900, [President] Hazard could report that it housed "a 12" refractor with micrometer, polarizing photometer, and star and sun spectroscopes. A Rowland concave grating spectroscope, of 6' focus, with its accompanying heliostat, is set up in a room capable of being darkened completely. The library is a beautiful room, and the dome by Warner and Swasey is all that it should be."When the observatory opened October 8, 1900, Professor Whiting became its first director and the college received "congratulatory letters from famous women astronomers in Europe." At the time Professor Whiting described it as "the finest student observatory in the country." The benefactor was heavily involved in the design of the facility, including the choice of white marble, and the selection of equipment. She also had strong opinions about the floor covering to be placed in the laboratory saying "it will be good for the girls to put their feet on an India rug."
Additional buildings
Soon after completion of the observatory, Professor Whiting began exploring plans for an expansion and went back to Mrs. Whitin, as she wrote in the trustee's obituary, which appeared in The Wellesley College News."I knew from the first that it was not large enough for the kind of work we wished to do, and that the nearest college residence hall was too far off for the astronomical staff to be present for the nightly vigil with the stars. Mrs. Whitin herself soon perceived this and of her own initiative began to think of an Observatory House, and an enlargement to the Observatory itself. The beauty and costliness of what was already done seemed difficult to match. Various compromise building materials for the addition were discussed, but after many consultations with the architect, she declared that "marble and copper were good enough," and by 1906 the observatory was doubled with increased equipment, and a house placed beside it, completing a harmonious group, and itself a lovely specimen of domestic architecture."
Timeline
Whitin Observatory strategic events, according to Wellesley College archives, follow.
Other philanthropic works
In addition to her efforts at the college, Whitin was a board member, and generous supporter, of the Baldwinsville Hospital for the Feeble Minded, for which she built a large school building, as well as the Hospital for the Insane in Worcester, Massachusetts.
Death
Sarah Elizabeth Whitin remained an active Wellesley Trustee until her illness the last two years of her life. She died on December 26, 1917. She is buried with her husband (and his first wife) in Pine Grove Cemetery, Whitinsville.
References
1836 births
1917 deaths
Whitin Observatory
Amateur astronomers
American women astronomers
People associated with astronomy | Sarah Elizabeth Whitin | [
"Astronomy"
] | 1,103 | [
"Astronomers",
"Amateur astronomers",
"People associated with astronomy"
] |
63,679,051 | https://en.wikipedia.org/wiki/Certificate%20of%20analysis | A certificate of analysis (COA) is a formal laboratory-prepared document that details the results of (and sometimes the specifications and analytical methods for) one or more laboratory analyses, signed—manually or electronically—by an authorized representative of the entity conducting the analyses. This document gives assurances to the recipient that the analyzed item is what it is designated to be, or has the features advertised by the producer. The design and content of a COA may be based upon a set of requirements identified by the lab, by regulatory-driven requirements, and/or by standards developed by standard developing organizations. The COA is used in a wide variety of industries, including but not limited to the agriculture, chemical, clinical research, food and beverage, and pharmaceutical industries.
Use in various industries
The COA is typically used in industries where the quality of a produced good is of significant importance and the COA recipient needs assurances of that quality. By extension, this often means regulations, standards, and/or guidelines are in place to better ensure analyses are approved and reported correctly. For example, regulations, standards, and/or guidelines affect COA use in agriculture, chemical, clinical research, food and beverage, and pharmaceutical industries. The COA may be used as a certification of product quality, an identification document, or a comparison document, depending upon the context.
Cannabis industry
A certificate of analysis can be associated with cannabis and cannabis-derived products, attesting to their laboratory analysis for cannabinoids, adulterants, heavy metals, pesticides, mold, etc. This gives consumers "an easy way to review test results from responsible companies selling cannabis and cannabis-infused products".
In the United States, , the regulatory mandate for requiring a COA is driven by state law, which can vary significantly. States like California and Maine lay out clear regulations concerning how cannabis and cannabis products are reported on a COA. Other states may not regulate COAs. Additionally, products containing cannabidiol (CBD), a non-psychoactive constituent of cannabis that is capable of being extracted from hemp, are not mandated to have a corresponding COA by the U.S. government, though some states like Indiana require a COA for CBD, along with a scannable QR code.
Contents and delivery of a COA
As regulations across counties, states, territories, countries, and supranational unions can vary, the contents and delivery/inclusion mechanisms for COAs will vary. Broadly speaking, however, the following represent elements that may be common to a COA:
the demographics and other identifiers for the supplier of the product/material/sample
the demographics and license information for the laboratory conducting the analyses
the demographics or details of any ancillary entities associated with the tested product (e.g., distributor or cultivator, as with cannabis products)
a clear description of the identity of the product/material/sample
a clear identifier of what type of testing was performed (e.g., "regulatory compliance testing")
any associated batch numbers, sample numbers, etc.
a chain of custody of the product/sample being tested, including dates, times, and relevant photos
the weight or unit count of the product/material/sample
the quality and concentration of the product/material/sample
the analytical methods (standard and non-standard), analytical instrumentation, and specifications (e.g., limits of detection and quantitation)
the analytical results, dated and presented in "a uniform, accurate, and concise manner", with a clear indication of passing or failing, when applicable
a key for abbreviations/initialisms and what they mean
the signature of the authorized person who performed or approved the analysis, as well as contact information and qualifications
the initials or signature of the authorized person who corrected the COA (if permitted), plus a clear identifier indicating the COA is corrected
In the case of a produced chemical, drug, ingredient, or standard, the manufacturer will likely include a COA for the end user. In the case of a tested product/material/sample, the recipient of the COA will be the entity that ordered the analysis or mandated the test via regulation, as with cannabis testing. If a regulatory body mandated the test, they will designate how the results should be delivered, whether physically or electronically. In the case of cannabis testing, electronic upload to a track and trace system may be mandated.
References
Cannabis
Laboratory techniques
Manufacturing | Certificate of analysis | [
"Chemistry",
"Engineering"
] | 896 | [
"Mechanical engineering",
"nan",
"Manufacturing"
] |
63,679,224 | https://en.wikipedia.org/wiki/Big-little-big%20lemma | In the mathematics of paper folding, the big-little-big lemma is a necessary condition for a crease pattern with specified mountain folds and valley folds to be able to be folded flat. It differs from Kawasaki's theorem, which characterizes the flat-foldable crease patterns in which a mountain-valley assignment has not yet been made. Together with Maekawa's theorem on the total number of folds of each type, the big-little-big lemma is one of the two main conditions used to characterize the flat-foldability of mountain-valley assignments for crease patterns that meet the conditions of Kawasaki's theorem. Mathematical origami expert Tom Hull calls the big-little-big lemma "one of the most basic rules" for flat foldability of crease patterns.
Statement
The lemma concerns the angles made by consecutive pairs of creases at a single vertex of the crease pattern. It states that if any one of these angles is a local minimum (that is, smaller than the two angles on either side of it), then exactly one of the two creases bounding the angle must be a mountain fold and exactly one must be a valley fold.
Generalization and applications
A generalized version of the lemma holds for a sequence of equal angles at a single vertex, surrounded on both sides by a larger angle. For such a sequence, the number of mountain and valley folds bounding any of these angles must either be equal, or differ by one. It can be used as part of a linear time algorithm that tests whether a folding pattern with a single vertex can be folded flat, by repeatedly looking for sequences of angles that obey the lemma and pinching them off, until either getting stuck or reducing the input to two equal angles bounded by two creases of the same type as each other.
History
In their book Geometric Folding Algorithms, Erik Demaine and Joe O'Rourke credit the lemma to publications of Toshikazu Kawasaki in 1989, and Jacques Justin in 1994.
References
Paper folding
Lemmas | Big-little-big lemma | [
"Mathematics"
] | 420 | [
"Recreational mathematics",
"Mathematical problems",
"Mathematical theorems",
"Lemmas",
"Paper folding"
] |
63,681,004 | https://en.wikipedia.org/wiki/Olio%20Model%20One | The Olio Model One is a discontinued smartwatch sold from 2015 to 2016 by the now defunct Olio Devices, Inc.
History
Olio Devices, Inc. was founded in 2013 by Steven K. Jacobs, Dr. Ashley J. "AJ" Cooper, and Evan Wilson. Two years later in 2015 they sold the first of their flagship watches. Olio Devices was acquired by Flex Ltd. in 2017. Olio Devices never sold any more watches after being acquired by Flex; later in 2017, Olio Devices' servers ceased to be online.
Hardware
The Olio features a single-core 600 MHz Texas Instruments OMAP3430 CPU, 512 megabytes of LPDDR RAM, 1 gigabyte of NAND flash memory, a Broadcom BCM20702 Low Energy-capable Bluetooth 4.0 transceiver, a Texas Instruments DRV2605 Haptic Driver, an ambient light sensor, a microphone, a rechargeable lithium polymer battery, a wireless charging coil, and a touchscreen. The Bluetooth MAC address of every Olio watch starts with B0:C5:CA:D0.
Software
The Olio watch comes preinstalled with the Android operating system with a custom user interface and startup logo. The system uses the Das U-Boot bootloader. At first boot, the watch will instruct the user to create a Bluetooth pairing between the watch and a smartphone. After doing so, the watch will display the text "Open Smartphone App". This is referring to the Olio Assist app, a companion smartphone app required to configure the Olio. Although previously available for iOS on the App Store and for Android on Google Play, the Olio Assist app is no longer available on either. The Olio Assist app can then be used to configure various features of the Olio watch. The app will automatically set the time on the watch from the phone's clock.
The Olio Smartwatch and the Olio Assist app communicate over a custom RFCOMM protocol. The app hosts the protocol on an available RFCOMM port and advertises that port over service discovery protocol with the UUID 11e63bf3-6baa-47d9-b31d-6045138c9add. The watch sends SDP queries to the phone (once every few seconds on the setup screen and once every time it turns its screen on after having been configured) until it sees that UUID, then connects to the RFCOMM port associated with it. At this point, the watch and app communicate with a binary format based on MessagePack. This protocol can be used to update the watch's underlying Android system: zip archives sent over this protocol will be extracted to the directory /data/media/0/olio/firmware_updates_apply/ in the internal filesystem; then, the watch executes the file /data/media/0/olio/firmware_updates_apply/update.sh (/update.sh in the archive) as root.
The Olio watch includes several pieces of software licensed under the GNU General Public License, such as the Linux kernel and U-Boot, but Olio Devices never released the source code to any of this software, thus violating the General Public License.
Sales
Olio Devices sold the Olio in "batches" of 1,000 each. Five batches were completely sold out, for a total of 5,000 watches sold. The Olio was sold in four "collections" (colors): a black collection, a steel (silver) collection, a gold collection, and a rose gold collection.
Production
The Olio watch was manufactured on contract by Flex Ltd., the company that would later acquire Olio Devices. Some of the watch's components were manufactured in China; this can be seen on the charger sold to consumers, which is engraved with "Made In China". Furthermore, prototype Olios had "ASSEMBLED IN CHINA" printed on the back casing. The Olio's motherboard, meanwhile, appears to have been manufactured in the United States, as it has "MADE IN USA" printed on it.
Planned future generations
Olio Devices had planned to sell an Olio Model Two by 2016, but ultimately did not do so. According to Jacobs, the Model Two would have focused on variation, rather than being an enhancement to or exploiting planned obsolescence of the Model One. Furthermore, the Model One was designed to be modular, so that individual components could be upgraded without replacing the whole device. Olio Devices never utilized this, either.
References
Smartwatches
Computer-related introductions in 2015 | Olio Model One | [
"Technology"
] | 964 | [
"Smartwatches"
] |
63,681,020 | https://en.wikipedia.org/wiki/List%20of%20CBRN%20warfare%20forces | Many countries around the world maintain military units that are specifically trained to cope with CBRN (Chemical, Biological, Radiological, Nuclear) threats. Beside this specialized units, most modern armed forces undergo generalized basic CBRN self-defense training for all their personnel.
Albania
Central Laboratory of the Armed Forces – Military Unit Nr.4010 (Laboratori Qendror i Forcave të Armatosura - Rep. Usht. Nr.4010)
Argentina
Army
601st Chemical Biological Nuclear and Emergency Support Engineers Company (Compañía de Ingenieros de Defensa Quimica Bacteriologica Nuclear y Apoyo a la Emergencia 601)
Navy
Chemical Biological Nuclear-Radiological Defense Department (Departamento Defensa Quimica Bacteriologica Nuclear-Radiológica)
Australia
Special Operations Engineer Regiment
Austria
Atomic, Biological, Chemical (ABC) Defense School "Lise Meitner" (Atomar, Biologisch, Chemisch (ABC)-Abwehrschule "Lise Meitner")
ABC Defense Company - 3rd Headquarters Battalion (ABC-Abwehrkompanie - Stabsbataillon 3)
ABC Defense Company - 4th Armored Headquarters Battalion (ABC-Abwehrkompanie - Panzerstabsbataillon 4)
ABC Defense Company - 6th Headquarters Battalion (ABC-Abwehrkompanie - Stabsbataillon 6)
ABC Defense Company - 7th Headquarters Battalion (ABC-Abwehrkompanie - Stabsbataillon 7)
Belgium
Competence Center – Engineer Department (Centre de Compétence - Département Génie)
Chemical Biological Radiological, Nuclear Company – 4th Engineer Battalion (Compagnie Chimique, Biologique, Radiologique, Nucléaire - 4 Bataillon du Génie)
Belarus
Department of Radiation, Chemical and Biological (RCB) Protection and Ecology ( Упраўленне радыяцыйнай, хімічнай i біялагічнай (РХБ) абароны і экалогіі – Upraŭliennie Radyjacyjnaj, Chimičnaj i Bijalahičnaj (RCB) Abarony i Ekalohii)
8th RBC Protection Regiment (8-я полк РХБ абаро́ны - 8-ja Polk RCB Abaróny)
Bosnia and Herzegovina
Atomic-Biological-Chemical Defense Company (Čete Atomsko-Biološko-Hemijske Odbrane)
Brazil
Army
1st Chemical Biological Radiological and Nuclear Defense Battalion (1º Batalhão de Defesa Química, Biológica, Radiológica e Nuclear)
Radiological and Nuclear Defense Company - Special Operations Command (Companhia de Defesa Química, Biológica, Radiológica e Nuclear - Comando de Operações Especiais)
Navy
Nuclear, Biological, Chemical and Radiological Defense Center (Centro de Defesa Nuclear, Biológica, Química e Radiológica)
Nuclear, Biological, Chemical and Radiological Defense Battalion – Aramar Experimental Center (Batalhão de Defesa Nuclear, Biológica, Química e Radiológica - Centro Experimental Aramar)
Nuclear, Biological, Chemical and Radiological Defense Company – Naval Fusiliers Engineer Battalion (Companhia de Defesa Nuclear, Biológica, Química e Radiológica - Batalhão de Engenharia de Fuzileiros Navais)
Bulgaria
38th Nuclear, Chemical and Biological Defense Battalion (38-ми батальон за ядрена, химическа и биологична защита - 38-mi Batal'on za Yadrena, Khimicheska i Biologichna Zashtita)
Brunei
Chemical, Biological, Radiological and Explosive Company of the Support Battalion
Canada
Canadian Joint Incident Response Unit
Canadian Forces Nuclear Biological Chemical School
China (People's Republic of Chin
(陆军防化学院 - Lùjūn Fáng Huà Xuéyuàn)
71st Chemical Defense Brigade - 71st Group Army
72nd Chemical defense brigade - 72nd Group Army
73rd Chemical defense brigade - 73rd Group Army
74th Chemical defense brigade - 74th Group Army
75th Chemical defense brigade - 75th Group Army
76th Chemical defense brigade - 76th Group Army
77th Chemical defense brigade - 77th Group Army
78th Chemical defense brigade - 78th Group Army
79th Chemical defense brigade - 79th Group Army
80th Chemical defense brigade - 80th Group Army
81st Chemical defense brigade - 81st Group Army
82nd Chemical defense brigade - 82nd Group Army
83rd Chemical defense brigade - 83rd Group Army
84th Chemical Defense Brigade - Tibet Military Region
- Xinjiang Military Region, stationed in Shuimogou district, Urumqi
China (Republic of China/"Taiwan")
Detection and Decontamination Battalion, 33rd Chemical Troops Group (33化學兵群偵消營- 33 Huàxué Bīng Qún Zhēn Xiāo Yíng )
Detection and Decontamination Battalion, 36th Chemical Troops Group (36化學兵群偵消營- 36 Huàxué Bīng Qún Zhēn Xiāo Yíng )
Detection and Decontamination Battalion, 39th Chemical Troops Group (39化學兵群偵消營- 39 Huàxué Bīng Qún Zhēn Xiāo Yíng )
Colombia
80th Disasters Awareness and Prevention Battalion "Brigadier General General Álvaro López Vargas" (Batallón de Atención y Prevención a Desastres No. 80 "Brigadier General Álvaro López Vargas")
Nuclear, Biological and Chemical Company (Compañía Nuclear, Biológico y Químico)
Croatia
Nuclear Biological and Chemical Defense Battalion (Bojna Nuklearno-Biološko-Kemijske Obrane)
Cuba
Chemical Defense Company (Compañía de Defensa Química)
Cyprus Republic
Nuclear Biological and Chemical Substances Protection Team (Ομάδα Προστασίας από Πυρηνικές Βιολογικές και Χημικές Ουσίες - Omáda Prostasías apó Pyrinikés Viologikés kai Chimikés Ousíes)
Czech Republic
31st Radiological, Chemical and Biological (RCB) Protection Regiment (31. Pluk Radiační, Chemické a Biologické (RCB) Ochrany)
311st RCB Protection Battalion (311. Prapor RCB Ochrany)
312th RCB Protection Battalion (312. Prapor RCB Ochrany)
314th Weapons of Mass Destruction Center (314. Centrum Výstrahy Zbraní Hromadného Ničení)
Denmark
3rd Chemical Biological Radiological Nuclear and Construction Battalion (3 Kemisk Biologisk Radiologisk Atomar & Konstruktionsbataljon)
Finland
CBRN Company – Engineer and Signal Battalion "Satakunta" (Suojelukomppania - Satakunnan Pioneeri- ja Viestipataljoona)
France
Army
2nd Dragoon Regiment (2e Regiment de Dragons)
Nuclear, Biological and Chemical Defense Center (Centre de Défense Nucléaire, Biologique et Chimique)
Army Medical Decontamination Unit (Unité Médicale de Décontamination des Armées)
Navy
Nuclear, Biological and Chemical Defense Platoon, Commando Kieffer (Section de Défense Nucléaire, Biologique et Chimique, Commando Kieffer)
Air Force
Nuclear, Biological and Chemical Intervention Platoon, Air Fire Brigade (Section d'intervention Nucléaire, Biologique et Chimique, Pompiers de l'Air)
Germany
Armed Forces Atomic-Biological-Chemical (ABC) Defense Command (ABC-Abwehrkommando der Bundeswehr)
7th ABC Defense Battalion (ABC-Abwehrbataillon 7)
750th ABC Defense Battalion "Baden" (ABC-Abwehrbataillon 750 "Baden")
906th ABC Defense Battalion (Reserve) (ABC-Abwehrbataillon 906 (Reserve))
907th ABC Defense Battalion (Reserve) (ABC-Abwehrbataillon 907 (Reserve))
ABC Defense and Legal Protection Tasks School (Schule ABC-Abwehr und Gesetzliche Schutzaufgaben)
Greece
Nuclear Biological Chemical Defense Special Joint Battalion (Ειδικό Διακλαδικό Λόχο Πυρηνικής Βιολογικής Χημικής Άμυνας - Eidikó Diakladikó Lócho Pyrinikís Viologikís Chimikís Ámynas)
Hungary
93rd Chemical Protection Battalion "Sándor Petőfi" (MH 93. Petőfi Sándor Vegyivédelmi Zászlóalj)
India
Army
Faculty of Nuclear Biological Chemical Protection - College of Military Engineering.
Air Force
Air Force Institute of Nuclear Biological Chemical Protection.
Integrated Defence Staff
The IDS has established various Joint Service Training Institutes under the Centre for Joint Warfare Studies for training Army, Navy and Air force personnel on the subject of CBRN warfare, Military law, intelligence etc.
National Disaster Response Force
NDRF has special cbrn companies trained on the guidelines of NDMA.
Central Industrial Security Force
The NDMA has also trained various units of cisf in first hand cbrn disaster management and hazard disposal.
Central Reserve Police Force
RAF battalions have special cbrn companies.
Border Security Force
BSF has also developed cbrn capabilities for the sake of emergency disposals.
Indonesia
Army Engineers Nuclear, Biological, and Chemical Company (Kompi Zeni Nuklir, Biologi dan Kimia)
CBRN Team 903rd Det. Satbravo 90 Kopasgat
Iran
Islamic Revolutionary Guard Corps
Nuclear Command Corps
24th Chemical Warfare Brigade "Bessat"
Israel
76th Chemical Defense Battalion (76 גדוד הסיוע הכימי - G'dud Siyua Khiymik 76)
Italy
Joint Nuclear, Biological and Chemical Defense School (Scuola Interforze per la Difesa Nucleare, Biologica e Chimica)
Chemical, Biological, Radiological and Nuclear Battalion "Rieti" (Battaglione Chimico, Biologico, Radioattivo e Nucleare "Rieti")
7th Chemical, Biological, Radiological and Nuclear Defense Regiment "Cremona" (7° Reggimento Difesa Chimica, Biologica, Radioattiva e Nucleare "Cremona")
Japan
Ground Self-Defense Force Chemical School (陸上自衛隊化学学校 - Rikujō Jieitai Kagaku Gakkō)
Central Special Weapons Protection Unit (中央特殊武器防護隊 – Chūō Tokushu Buki Bōgotai)
one Special Weapons Protection Battalion (特殊武器防護大隊 - Tokushu Buki Bogodaitai) in each Division.
one Special Weapons Protection Company (特殊武器防護中隊 - Tokushu Buki Bogochūtai) in each independent Brigade.
Jordan
Chemical Support Unit (حدة دعم الكيميائية - Hdt Dem al-Kymyayyt)
Kazakhstan
Department of Radiation, Chemical, Biological Protection and Environmental Troops (Радиациялық, Химиялық, Биологиялық Қорғау Және Экологиялық Әскерлері Департаменті - Radïacïyalıq, Xïmïyalıq, Bïologïyalıq Qorğaw Jäne Éékologïyalıq Ääskerleri Departamenti)
Korea (Democratic People's Republic of Korea/"North Korea")
Nuclear-Chemical Defense Bureau
13th Nuclear-Chemical Defense Battalion (Reserve)
14th Nuclear-Chemical Defense Battalion (Reserve)
15th Nuclear-Chemical Defense Battalion (Reserve)
16th Nuclear-Chemical Defense Battalion (Reserve)
17th Nuclear-Chemical Defense Battalion
18th Nuclear-Chemical Defense Battalion
27th Nuclear-Chemical Defense Battalion (Reserve)
36th Nuclear-Chemical Defense Battalion (Reserve)
Korea (Republic of Korea/"South Korea")
Army Chemical School (육군화생방학교 – Yuggun Hwasangbang Haggyo)
10th Chemical Battalion (제10화생방대대 – je 10 Hwasangbang Daedae)
11th Chemical Battalion (제11화생방대대 – je 11 Hwasangbang Daedae)
12th Chemical Battalion (제12화생방대대 – je 12 Hwasangbang Daedae)
13th Chemical Battalion (제13화생방대대 – je 13 Hwasangbang Daedae)
15th Chemical Battalion (제15화생방대대 – je 15 Hwasangbang Daedae)
17th Chemical Battalion (제17화생방대대 – je 17 Hwasangbang Daedae)
19th Chemical Battalion (제19화생방대대 – je 19 Hwasangbang Daedae)
Latvia
National Guard Weapons of Mass Destruction Protection Company (Aizsardzības no Masveida Iznīcināšanas Ieročiem Rota)
Lebanon
Weapons of Mass Destruction Defense Company (سرية الوقاية من اسلحة الدمار الشامل - Siriyat al-Wiqayat min 'as-Lihat al-Damar al-Shshamil)
Lithuania
Atomic Biological and Chemical Platoon - Engineer Battalion "Juozo Vitkaus" (Atomines Biologines ir Chemines Būrys - "Juozo Vitkaus" Inžinerijos Vatalione)
Macedonia (Republic of North Macedonia)
Nuclear Biological Chemical Protection Company (Чета за нуклеарна биолошка хемиска одбране - Četa za Nuklearna Biološka Xemiska Odbrana)
Malaysia
3rd Chemical, Biological and Nuclear Warfare Division (Peperangan Nuklear, Biologi dan Kimia 3 Divisyen)
Mexico
Chemical, Biological and Radiological Emergencies Response Group (Grupo de Respuesta de Energencias Quimicas, Biologicas y Radiologicas)
Moldova
Independent Chemical Protection Company (Compania Protecţie Chimică Independentă)
Montenegro
Chemical Biological Radiological Nuclear (CBRN) Defence Platoon of the Infantry Battalion (Вода Xемијско, Биолошко, Радиолошко Нуклеарно Одбрање (ХРБНО)/Пешадијски Батаљон - Voda Hemijsko, Biološko, Radiološko, Nuklearno Odbranje (HRBNO)/Pešadijski Bataljon)
NATO
Joint Chemical, Biological, Radiological and Nuclear (CBRN) Defense Centre of Excellence
Combined Joint CBRN Defence Task Force
CBRN Joint Assessment Team
Multinational CBRN Defence Battalion
Netherlands
Defense Chemical Biological Radiological Nuclear (CBRN) Center (Defensie Chemisch Biologisch Radiologisch Nucleair (CBRN) Centrum)
CBRN Response Unit (CBRN Respons Eenheid)
CBRN Training Center (Nationaal Trainingscentrum CBRN)
New Zealand
E Squadron – 1st New Zealand Special Air Service Regiment
Norway
Engineers Battalion Chemical Biological Radiological and Nuclear Company (Ingeniørbataljonens CBRN-kompani)
Peru
Nuclear, Bacteriological and Chemical Defense Department - Army Scientific and Technological Research Center (División de Defensa Nuclear, Bacteriológica y Química - Centro de Investigación Científico Tecnológico del Ejército)
Philippines
Army
Chemical Biological Radiological Nuclear Platoon – Explosive Ordnance Battalion
Air Force
Chemical Biological Radiological Nuclear Team - 710th Special Operations Wing
Poland
Engineering and Chemical Forces Training Center "General Jakub Jasiński" (Centrum Szkolenia Wojsk Inżynieryjnych i Chemicznych im. gen. Jakuba Jasińskiego)
4th Chemical Regiment "Ignacy Mościcki" (4 Pułk Chemiczny im. Ignacego Mościckiego)
5th Chemical Regiment "Lieutenant General Leon Berbecki" (5 Pułk Chemiczny im. gen. broni Leona Berbeckiego)
Armed Forces Epidemiological Response Center (Centrum Reagowania Epidemiologicznego Sił Zbrojnych)
Portugal
Nuclear, Biological, Chemical and Radiological Defense Company – 1st Engineer Regiment (Companhia de Defesa Nuclear, Biológica, Química e Radiológica - Regimento de Engenharia N.º1)
Chemical, Biological, Radiological and Nuclear Defense Flight - Air Force Survival Training Center (Esquadrilha de Defesa Nuclear, Radiológica, Biológica e Química - Centro de Treino de Sobrevivência da Força Aérea)
Romania
Nuclear, Biological and Chemical (NBC) Defense Training Base (Baza de Instruire pentrul Apărare Nucleară, Biologică şi Chimică (NBC))
49th NBC Defense Battalion "Argeş" (Batalionului 49 Apãrare NBC "Argeş")
72nd NBC Defense Battalion "Black Voivode" (Batalionului 72 Apãrare NBC "Negru Vodă")
202nd NBC Defense Battalion "General Gheorghe Teleman" (Batalionului 202 Apãrare NBC "Gen. Gheorghe Teleman")
Russian Federation
Russian NBC Protection Troops (Войска́ радиацио́нной, хими́ческой и биологи́ческой (РХБ) защи́ты Вооружённых сил Росси́йской Федера́ции - Voyská Radiatsiónnoy, Khimícheskoy i Biologícheskoy (RKhB) Zashchíty Vooruzhonnykh sil Rossíyskoy Federátsii)
1st Mobile RCB Protection Brigade (1-я мобильная бригада РХБ защиты -1-ya Mobil'naya Brigada RKhB Zashchity)
16th Independent RCB Protection Brigade "Khingansk" (16-я отдельная Хинганская бригада РХБ защиты - 16-ya Otdel'naya Khinganskaya Brigada RKHB Zashchity)
27th Independent RCB Protection Brigade (27-я отдельная бригада РХБ защиты - 27-ya Otdel'naya Brigada RKhB Zashchity)
28th Independent RCB Protection Brigade (28-я отдельная бригада РХБ защиты - 28-ya Otdel'naya Brigada RKhB Zashchity)
29th Independent RCB Protection Brigade "Colonel-General "V.K. Pikalov" (29-я отдельная бригада РХБ защиты имени генерал-полковника В. К. Пикалова - 29-ya Otdel'naya Brigada RKhB Zashchity imeni general-polkovnika V. K. Pikalova)
2nd RCB Protection Regiment (2-й полк РХБ защиты - 2-y Polk RKhB Zashchity)
4th RCB Protection Regiment (4-й полк РХБ защиты - 4-y Polk RKhB Zashchity)
6th RCB Protection Regiment (6-й полк РХБ защиты - 6-y Polk RKhB Zashchity)
9th RCB Protection, Marking and Reconnaissance Regiment (9-й полк РХБ защиты, засечки и разведки - 9-y Polk RKHB Zashchity, Zasechki i Razvedki)
10th RCB Protection Regiment (10-й полк РХБ защиты - 10-y Polk RKhB Zashchity)
19th RCB Protection Regiment (19-й полк РХБ защиты - 19-y Polk RKhB Zashchity)
20th RCB Protection Regiment (20-й полк РХБ защиты - 20-y Polk RKhB Zashchity)
25th RCB Protection Regiment (25-й полк РХБ защиты - 25-y Polk RKhB Zashchity)
26th RCB Protection Regiment (26-й полк РХБ защиты - 26-y Polk RKhB Zashchity)
35th RCB Protection Regiment (35-й полк РХБ защиты - 35-y Polk RKhB Zashchity)
39th RCB Protection Regiment (39-й полк РХБ защиты - 39-y Polk RKhB Zashchity)
40th RCB Protection Regiment (40-й полк РХБ защиты - 40-y Polk RKhB Zashchity)
282nd RCB Military Training Center (282-й учебный центр войск РХБ защиты - 282-y Uchebnyy Tsentr Voysk RKhB Zashchity)
345th Operational Coordination Center of the Unified System for Identifying and Assessing the Scale of the Use of Weapons of Mass Destruction and Accidents at RCB Hazardous Facilities (345-й оперативно-координационный центр единой системы выявления и оценки масштабов применения оружия массового поражения и аварий на RKhB опасных объектах - 345-y Operativno-Koordinatsionnyy Tsentr Yedinoy Sistemy Vyyavleniya i Otsenki Masshtabov Primeneniya Oruzhiya Massovogo Porazheniya i Avariy na RKhB opasnykh ob"yektakh)
Military Academy of RCB Protection "Marshal of the Soviet Union Semën Konstantinovič Timošenko" (Военная академия РХБ защиты имени Маршала Советского Союза Семёна Константиновича Тимошенко - Voyennaya Akademiya RKhB Zashchity imeni Marshala Sovetskogo Soyuza Semyon Konstantinovich Timoshenko)
one RCB Protection Company in each Brigade
Navy
Department of RCB Protection (Кафедра РХБ защиты - Kafedra RKHB Zashchity)
National Guard
4th Independent RCB Protection Company (4-я отдельная рота РХБ защиты - 4-ya Otdel'naya Rota RKHB Zashchity)
6th Independent RCB Protection Company (6-я отдельная рота РХБ защиты - 6-ya Otdel'naya Rota RKHB Zashchity)
Saudi Arabia
Weapons of Mass Destruction Defense School (مدرسة الوقاية من أسلحة الدمار الشامل - Madrasat al-Wiqayat min 'as-Lihat al-Damar al-Shshamil)
Serbia
Atomic-Biological-Chemical (ABC) Service (Атомско-биолошко-хемијска (АБХ) служба - Atomsko-Biološko-Hemijska (ABH) Služba)
ABC Defense Center (Центар АБХ одбране - Centar ABH Odbrane)
246th ABC Defense Battalion (246. батаљон АБХ одбране - 46. Bataljon ABH Odbrane)
Singapore
Chemical, Biological, Radiological and Explosives Defence Group
Slovakia
Radiation, Chemical and Biological Protection Battalion (Prápor Radiačnej, Chemickej a Biologickej Ochrany)
Slovenia
18th Nuclear, Radiological, Chemical and Biological Defense Battalion (18. Bataljon za Jedrsko, Radiološko, Kemično in Biološko Obrambo)
South Africa
Chemical Biological Warfare Wing - 7 Medical Battalion Group
Spain
1st Nuclear Biological Chemical (NBC) Regiment "Valencia" (Regimento de Defensa Nuclear Biologica Quimica (NBQ) "Valencia" n° 1)
NBC Defense Military School (Escuela Militar de Defensa NBQ)
Epidemic Investigation Rapid Deployment Team - Central Defense Hospital "Gómez Ulla" (Equipo Desplegable Rápido de Investigación de Brotes - Hospital Central de la Defensa "Gómez Ulla")
one NBC Defense Company in each brigade
Sri Lanka
Army
14th Chemical Biological Radiology and Nuclear (CBRN) Regiment (14 වන රසායනික ජීව විද්යාත්මක විකිරණශීලී හා න්යෂ්ටික රෙජිමේන්තුව - 14 Vana Rasāyanika Jīva Vidyātmaka Vikiraṇaśīlī hā Nyaṣṭika Rejimēntuva)
Navy
Naval Nuclear Biological Chemical Defense School (නාවික න්යෂ්ටික ජීව විද්යාත්මක රසායනික ආරක්ෂක පාසල - Nāvika Nyaṣṭika Jīva Vidyātmaka Rasāyanika Ārakṣaka Pāsala)
Air Force
No.49 CBRN and Explosive Wing (රසායනික ජීව විකිරණ හා න්යෂ්ටික පුපුරණ ද්රව්ය පක්ෂාංගය - Rasāyanika Jīva Vikiraṇa hā Nyaṣṭika Pupuraṇa Dravya Pakṣāṁgaya)
Sweden
Total Defense Protection Center (Totalförsvarets Skyddscentrum)
Switzerland
Atomic, Biological, Chemical (ABC), De-mining and Unexploded Ordnance Disposal Competence Center (Kompetenzzentrum Atomar, Biologisch, Chemisch (ABC), Kampfmittelbeseitigung und Minenräumung - Centre de Compétences Nucléaire, Biologique, Chimique (NBC), Dé-minage et d'Elimination des Munitions non Explosées - Centro di Competenza Nucleare, Biologico Chimico (NBC), Eliminazione di Munizioni Inesplose e Sminamento)
77th ABC Defense School (ABC-Abwehr Schule 77 - École de Défense NBC 77 - Scuola di Difesa NBC 77)
10th ABC Defense Battalion (ABC-Abwehrbataillon 10 - Bataillon de Défense NBC 10 - Battaglione di Difesa NBC 10)
ABC Defense Intervention Company (ABC-Abwehr Einsatzkompanie - Companie d'Engagement de Défense NBC - Compagnia d'Intervento di Difesa NBC)
Tajikistan
74th Radiation Chemical and Biological Company (74-я Рота Радиацио́нной, Хими́ческой и Биологи́ческой - 74—ya Radiatsiónnoy, Khimícheskoy i Biologícheskoy)
Thailand
Royal Thai Army Chemical Department (RTACD)
Naval Science Department (NSD)
Research and Development Centre for Space and Aeronautical Science and Technology, RTAF (RDC)
Turkey
Chemical Biological Radiological Nuclear (CBRN) Defense Battalion (Kimyasal Biyolojik Radyolojik Nükleer (KBRN) Savunma Tabur), including:
CBRN Defense Special Response Unit (KBRN Savunma Özel Müdahale Birliği)
CBRN School and Training Center Command (KBRN Okul ve Eğitim Merkezi)
Ukraine
1st NPP Battalion
3rd NPP Battalion
4th NPP Battalion
5th NPP Battalion
704th Independent Radiation, Chemical, Biological (RCB) Protection Brigade (704-й окремий полк радіаційного, хімічного, біологічного (РХБ) захисту - 704-y Okremyy Polk Radiatsiynoho, Khimichnoho, Biolohichnoho (RKhB) Zakhystu)
536th Central Base of Repair and Storage (RCB Protection Weapons) (536-й центральна база ремонту і зберігання (озброєння РХБ захисту) - 536-y Tsentralʹna Baza Remontu i Zberihannya (Ozbroyennya RKhB Zakhystu))
one RCB Protection Platoon in each Brigade
United Kingdom
Inter-services
Defense Chemical Biological Radiological and Nuclear Centre
Army
28 Engineer Regiment, Royal Engineers including:
"Falcon" Squadron - Royal Tank Regiment
Navy
Royal Marines
Zulu Company, 45 Commando
Air Force
No. 27 Squadron RAF Regiment
United States
Army
Chemical Corps
Army Chemical, Biological, Radiological and Nuclear School
84th Chemical Battalion (Training)
23rd Chemical Battalion
20th Chemical Biological Radiological Nuclear and Explosives (CBRN) Command
48th Chemical Brigade
2nd Chemical Battalion
22nd Chemical Battalion (Technical Escort)
83rd Chemical Battalion
110th Chemical Battalion (Technical Escort)
Chemical, Biological, Radiological, Nuclear, and Explosives Analytical and Remediation Activity
Army Reserve
415th Chemical Brigade (Army Reserve)
92nd Chemical Battalion (Army Reserve)
457th Chemical Battalion (Army Reserve)
479th Chemical Battalion (Army Reserve)
485th Chemical Battalion (Army Reserve)
490th Chemical Battalion (Army Reserve)
455th Chemical Brigade (Army Reserve)
450th Chemical Battalion (Army Reserve)
453rd Chemical Battalion (Army Reserve)
468th Chemical Battalion (Army Reserve)
472nd Chemical Battalion (Army Reserve)
Army National Guard
31st Chemical Biological Radiological and Nuclear Brigade (Alabama NG)
145th Chemical Battalion (Alabama NG)
151st Chemical Battalion (Alabama NG)
44th Chemical Battalion (Illinois NG)
103rd Chemical Battalion (Kentucky NG)
126th Chemical Battalion (Nebraska NG)
155th Chemical Battalion (Ohio NG)
420th Chemical Battalion (Washington NG)
Independent Companies
50th Chemical Company (New Jersey NG)
108th Chemical Company (South Carolina NG)
128th Chemical Company (Pennsylvania NG)
138th Chemical Company (Georgia NG)
140th Chemical Company (California NG)
222nd Chemical Company (New York NG)
229th Chemical Company (Virginia NG)
231st Chemical Company (Maryland NG)
272nd Chemical Company (Massachusetts NG)
434th Chemical Company (Minnesota NG)
436th Chemical Company (Texas NG)
438th Chemical Company (Indiana NG)
457th Chemical Company (Wisconsin NG)
460th Chemical Company (Michigan NG)
482nd Chemical Company (Puerto Rico NG)
631st Chemical Company (Montana NG)
704th Chemical Company (Minnesota NG)
Navy
Explosive Ordnance Disposal Group One
Explosive Ordnance Disposal Group Two
Marines
Chemical Biological Incident Response Force
Air Force
368th Training Squadron "Vikings"
Coast Guard
Maritime Security Response Team (MSRT)
Joint Army National Guard and Air National Guard
CBRN and High Yield Explosives Enhanced Response Force Packages (CERFP)
6th CERFP (Texas NG)
9th CERFP (California NG)
19th CERFP (Indiana NG)
34th CERFP (Virginia NG)
35th CERFP (West Virginia NG)
55th CERFP (Minnesota NG)
102nd CERFP (Oregon NG)
781st CERFP (Georgia NG)
Alabama National Guard CERFP
Colorado National Guard CERFP
Florida National Guard CERFP
Hawaii National Guard CERFP
Illinois National Guard CERFP
Kentucky National Guard CERFP
Louisiana National Guard CERFP
Nebraska National Guard CERFP
Nevada National Guard CERFP
New England CERFP (Maine, New Hampshire, Rhode Island and Vermont National Guard)
New York National Guard CERFP
Puerto Rico National Guard CERFP
Utah National Guard CERFP
Uruguay
Chemical, Biological, Radiological and Nuclear Group (Grupo Quimico, Biologico, Radiologico y Nuclear)
Uzbekistan
Training Center for Experts on Chemical, Biological, Radiation Safety
Vietnam
Chemical Arms (Binh chủng Hóa học)
Military Environmental Chemistry Institute (Viện Hóa học-Môi trường Quân sự)
Chemicals and Nuclear radiation Incident Response Center, North (Trung tấm Ứng phó sự cố hóa học, phóng xạ hạt nhân miền Bắc)
Chemicals and Nuclear radiation Incident Response Center, Central(Trung tấm Ứng phó sự cố hóa học, phóng xạ hạt nhân miền Trung)
Chemicals and Nuclear radiation Incident Response Center, South(Trung tấm Ứng phó sự cố hóa học, phóng xạ hạt nhân miền Nam)
See also
CBRN defense
List of cyber warfare forces
List of marines and similar forces
List of mountain warfare forces
List of paratrooper forces
References
Notes
Sources
CBRN
Units
CBRN | List of CBRN warfare forces | [
"Chemistry",
"Biology"
] | 7,375 | [
"Chemical",
" biological",
" radiological and nuclear defense",
"Biological warfare"
] |
63,682,456 | https://en.wikipedia.org/wiki/Ring%20and%20Ball%20Apparatus | Ring and Ball Apparatus is used to determine the softening point of bitumen, waxes, LDPE, HDPE/PP blend granules, rosin and solid hydrocarbon resins. The apparatus was first designed in the 1910s while ASTM adopted a test method in 1916. This instrument is ideally used for materials having softening point in the range of 30 °C to 157 °C.
Components
Two brass rings.
Two steel balls.
Two ball guides to hold the balls in position.
A Support to hold the rings, balls and thermometer in position
A Glass beaker
Thermometer
Hot plate
Magnetic stirrer
Glycerol or water as heating bath
Procedure
The solid sample is taken in a Petri dish and melted by heating it on a standard hot plate. The bubble free liquefied sample is poured from the Petri dish and cast into the ring. The brass shouldered rings in this apparatus have 6.4 mm depth. The cast sample in the ring is kept undisturbed for one hour to solidify. Excess material is removed with a hot knife. The ring is set with the ball on top with ball guides on the grooved plate within the heating bath. As the temperature rises, the balls begin to sink through the rings carrying a portion of the softened sample with it. The temperature at which the steel balls touch the bottom plate determines the softening point in degrees Celsius.
References
Temperature
Polymer chemistry | Ring and Ball Apparatus | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 288 | [
"Scalar physical quantities",
"Temperature",
"Thermodynamic properties",
"Physical quantities",
"SI base quantities",
"Intensive quantities",
"Materials science",
"Thermodynamics",
"Polymer chemistry",
"Wikipedia categories named after physical quantities"
] |
63,684,284 | https://en.wikipedia.org/wiki/Nuclear%20operator | In mathematics, nuclear operators are an important class of linear operators introduced by Alexander Grothendieck in his doctoral dissertation. Nuclear operators are intimately tied to the projective tensor product of two topological vector spaces (TVSs).
Preliminaries and notation
Throughout let X,Y, and Z be topological vector spaces (TVSs) and L : X → Y be a linear operator (no assumption of continuity is made unless otherwise stated).
The projective tensor product of two locally convex TVSs X and Y is denoted by and the completion of this space will be denoted by .
L : X → Y is a topological homomorphism or homomorphism, if it is linear, continuous, and is an open map, where , the image of L, has the subspace topology induced by Y.
If S is a subspace of X then both the quotient map X → X/S and the canonical injection S → X are homomorphisms.
The set of continuous linear maps X → Z (resp. continuous bilinear maps ) will be denoted by L(X, Z) (resp. B(X, Y; Z)) where if Z is the underlying scalar field then we may instead write L(X) (resp. B(X, Y)).
Any linear map can be canonically decomposed as follows: where defines a bijection called the canonical bijection associated with L.
X* or will denote the continuous dual space of X.
To increase the clarity of the exposition, we use the common convention of writing elements of with a prime following the symbol (e.g. denotes an element of and not, say, a derivative and the variables x and need not be related in any way).
will denote the algebraic dual space of X (which is the vector space of all linear functionals on X, whether continuous or not).
A linear map L : H → H from a Hilbert space into itself is called positive if for every . In this case, there is a unique positive map r : H → H, called the square-root of L, such that .
If is any continuous linear map between Hilbert spaces, then is always positive. Now let R : H → H denote its positive square-root, which is called the absolute value of L. Define first on by setting for and extending continuously to , and then define U on by setting for and extend this map linearly to all of . The map is a surjective isometry and .
A linear map is called compact or completely continuous if there is a neighborhood U of the origin in X such that is precompact in Y.
In a Hilbert space, positive compact linear operators, say L : H → H have a simple spectral decomposition discovered at the beginning of the 20th century by Fredholm and F. Riesz:
There is a sequence of positive numbers, decreasing and either finite or else converging to 0, and a sequence of nonzero finite dimensional subspaces of H (i = 1, 2, ) with the following properties: (1) the subspaces are pairwise orthogonal; (2) for every i and every , ; and (3) the orthogonal of the subspace spanned by is equal to the kernel of L.
Notation for topologies
σ(X, X′) denotes the coarsest topology on X making every map in X′ continuous and or denotes X endowed with this topology.
σ(X′, X) denotes weak-* topology on X* and or denotes X′ endowed with this topology.
Note that every induces a map defined by . σ(X′, X) is the coarsest topology on X′ making all such maps continuous.
b(X, X′) denotes the topology of bounded convergence on X and or denotes X endowed with this topology.
b(X′, X) denotes the topology of bounded convergence on X′ or the strong dual topology on X′ and or denotes X′ endowed with this topology.
As usual, if X* is considered as a topological vector space but it has not been made clear what topology it is endowed with, then the topology will be assumed to be b(X′, X).
A canonical tensor product as a subspace of the dual of Bi(X, Y)
Let X and Y be vector spaces (no topology is needed yet) and let Bi(X, Y) be the space of all bilinear maps defined on and going into the underlying scalar field.
For every , let be the canonical linear form on Bi(X, Y) defined by for every u ∈ Bi(X, Y).
This induces a canonical map defined by , where denotes the algebraic dual of Bi(X, Y).
If we denote the span of the range of 𝜒 by X ⊗ Y then it can be shown that X ⊗ Y together with 𝜒 forms a tensor product of X and Y (where x ⊗ y := 𝜒(x, y)).
This gives us a canonical tensor product of X and Y.
If Z is any other vector space then the mapping Li(X ⊗ Y; Z) → Bi(X, Y; Z) given by u ↦ u ∘ 𝜒 is an isomorphism of vector spaces.
In particular, this allows us to identify the algebraic dual of X ⊗ Y with the space of bilinear forms on X × Y.
Moreover, if X and Y are locally convex topological vector spaces (TVSs) and if X ⊗ Y is given the -topology then for every locally convex TVS Z, this map restricts to a vector space isomorphism from the space of continuous linear mappings onto the space of continuous bilinear mappings.
In particular, the continuous dual of X ⊗ Y can be canonically identified with the space B(X, Y) of continuous bilinear forms on X × Y;
furthermore, under this identification the equicontinuous subsets of B(X, Y) are the same as the equicontinuous subsets of .
Nuclear operators between Banach spaces
There is a canonical vector space embedding defined by sending to the map
Assuming that X and Y are Banach spaces, then the map has norm (to see that the norm is , note that so that ). Thus it has a continuous extension to a map , where it is known that this map is not necessarily injective. The range of this map is denoted by and its elements are called nuclear operators. is TVS-isomorphic to and the norm on this quotient space, when transferred to elements of via the induced map , is called the trace-norm and is denoted by . Explicitly, if is a nuclear operator then .
Characterization
Suppose that X and Y are Banach spaces and that is a continuous linear operator.
The following are equivalent:
is nuclear.
There exists a sequence in the closed unit ball of , a sequence in the closed unit ball of , and a complex sequence such that and is equal to the mapping: for all . Furthermore, the trace-norm is equal to the infimum of the numbers over the set of all representations of as such a series.
If Y is reflexive then is a nuclear if and only if is nuclear, in which case .
Properties
Let X and Y be Banach spaces and let be a continuous linear operator.
If is a nuclear map then its transpose is a continuous nuclear map (when the dual spaces carry their strong dual topologies) and .
Nuclear operators between Hilbert spaces
Nuclear automorphisms of a Hilbert space are called trace class operators.
Let X and Y be Hilbert spaces and let N : X → Y be a continuous linear map. Suppose that where R : X → X is the square-root of and U : X → Y is such that is a surjective isometry. Then N is a nuclear map if and only if R is a nuclear map;
hence, to study nuclear maps between Hilbert spaces it suffices to restrict one's attention to positive self-adjoint operators R.
Characterizations
Let X and Y be Hilbert spaces and let N : X → Y be a continuous linear map whose absolute value is R : X → X.
The following are equivalent:
N : X → Y is nuclear.
R : X → X is nuclear.
R : X → X is compact and is finite, in which case .
Here, is the trace of R and it is defined as follows: Since R is a continuous compact positive operator, there exists a (possibly finite) sequence of positive numbers with corresponding non-trivial finite-dimensional and mutually orthogonal vector spaces such that the orthogonal (in H) of is equal to (and hence also to ) and for all k, for all ; the trace is defined as .
is nuclear, in which case .
There are two orthogonal sequences in X and in Y, and a sequence in such that for all , .
N : X → Y is an integral map.
Nuclear operators between locally convex spaces
Suppose that U is a convex balanced closed neighborhood of the origin in X and B is a convex balanced bounded Banach disk in Y with both X and Y locally convex spaces. Let and let be the canonical projection. One can define the auxiliary Banach space with the canonical map whose image, , is dense in as well as the auxiliary space normed by and with a canonical map being the (continuous) canonical injection.
Given any continuous linear map one obtains through composition the continuous linear map ; thus we have an injection and we henceforth use this map to identify as a subspace of .
Definition: Let X and Y be Hausdorff locally convex spaces. The union of all as U ranges over all closed convex balanced neighborhoods of the origin in X and B ranges over all bounded Banach disks in Y, is denoted by and its elements are call nuclear mappings of X into Y.
When X and Y are Banach spaces, then this new definition of nuclear mapping is consistent with the original one given for the special case where X and Y are Banach spaces.
Sufficient conditions for nuclearity
Let W, X, Y, and Z be Hausdorff locally convex spaces, a nuclear map, and and be continuous linear maps. Then , , and are nuclear and if in addition W, X, Y, and Z are all Banach spaces then .
If is a nuclear map between two Hausdorff locally convex spaces, then its transpose is a continuous nuclear map (when the dual spaces carry their strong dual topologies).
If in addition X and Y are Banach spaces, then .
If is a nuclear map between two Hausdorff locally convex spaces and if is a completion of X, then the unique continuous extension of N is nuclear.
Characterizations
Let X and Y be Hausdorff locally convex spaces and let be a continuous linear operator.
The following are equivalent:
is nuclear.
(Definition) There exists a convex balanced neighborhood U of the origin in X and a bounded Banach disk B in Y such that and the induced map is nuclear, where is the unique continuous extension of , which is the unique map satisfying where is the natural inclusion and is the canonical projection.
There exist Banach spaces and and continuous linear maps , , and such that is nuclear and .
There exists an equicontinuous sequence in , a bounded Banach disk , a sequence in B, and a complex sequence such that and is equal to the mapping: for all .
If X is barreled and Y is quasi-complete, then N is nuclear if and only if N has a representation of the form with bounded in , bounded in Y and .
Properties
The following is a type of Hahn-Banach theorem for extending nuclear maps:
If is a TVS-embedding and is a nuclear map then there exists a nuclear map such that . Furthermore, when X and Y are Banach spaces and E is an isometry then for any , can be picked so that .
Suppose that is a TVS-embedding whose image is closed in Z and let be the canonical projection. Suppose all that every compact disk in is the image under of a bounded Banach disk in Z (this is true, for instance, if X and Z are both Fréchet spaces, or if Z is the strong dual of a Fréchet space and is weakly closed in Z). Then for every nuclear map there exists a nuclear map such that .
Furthermore, when X and Z are Banach spaces and E is an isometry then for any , can be picked so that .
Let X and Y be Hausdorff locally convex spaces and let be a continuous linear operator.
Any nuclear map is compact.
For every topology of uniform convergence on , the nuclear maps are contained in the closure of (when is viewed as a subspace of ).
See also
References
Bibliography
External links
Nuclear space at ncatlab
Topological vector spaces
Tensors
Operator theory
Topological tensor products
Linear operators | Nuclear operator | [
"Mathematics",
"Engineering"
] | 2,631 | [
"Functions and mappings",
"Tensors",
"Vector spaces",
"Mathematical objects",
"Linear operators",
"Topological vector spaces",
"Space (mathematics)",
"Mathematical relations",
"Topological tensor products"
] |
70,866,058 | https://en.wikipedia.org/wiki/Havfrue | Havfrue (Mermaid) is a submarine communications cable privately owned by Aqua Comms, Meta, Google and Bulk Infrastructure, linking the United States, Ireland and Denmark.
History
Havfrue comprises a main trunk beginning in New Jersey, USA (NJFX) and landing in Blaabjerg, Denmark, which comprises six fiber pairs. Two further branches connect Ireland (Old Head Beach, Leckanvy), with six fiber pairs and Norway (Kristiansand) with two fiber pairs.
The cable was laid by TE SubCom and has a designed capacity of 108 Tbit/s. The operator and landing party in the US, Ireland and Denmark is Aqua Comms, which will market and sell capacity services and raw spectrum under the brand name 'America Europe Connect-2' (AEC-2).
Bulk Fibre Networks is utilising Ciena’s Spectrum Sharing submarine network infrastructure to provide tailored virtual fiber pairs on its part of the infrastructure, as well as Ciena's GeoMesh Extreme submarine network solution and Manage, Control and Plan (MCP) domain controller, which provides network management capabilities.
The Havfrue/AEC-2 cable system was ready for service by 1 December 2020.
In 2023, EXA Infrastructure added Havfrue to its transatlantic subsea cable route network connecting USA and Europe.
Ownership
Meta owns two fiber pairs on the Main Trunk and two fiber pairs on the Ireland branch.
Aqua Comms owns two fiber pairs on the Main Trunk and four fiber pairs on the Ireland branch.
Google owns one fiber pair on the Main Branch.
Bulk Infrastructure owns one fiber pair on the Main Trunk and both fiber pairs on the Norway Branch.
References
Transatlantic communications cables
Submarine communications cables in the North Atlantic Ocean
Infrastructure completed in 2020
Ireland–United States relations
Coastal construction
Telecommunications equipment
History of telecommunications
2020 establishments in Ireland
2020 establishments in New York (state) | Havfrue | [
"Engineering"
] | 388 | [
"Construction",
"Coastal construction"
] |
70,866,088 | https://en.wikipedia.org/wiki/Azirinomycin | Azirinomycin is an antibiotic azirine derivative with the molecular formula C4H5NO2 which is produced by the bacterium Streptomyces aureus. Azirinomycin was first isolated in 1971. Azirinomycin is toxic and therefore it cannot not be used in human medicine.
References
Further reading
Antibiotics
Azirines
Carboxylic acids | Azirinomycin | [
"Chemistry",
"Biology"
] | 80 | [
"Biotechnology products",
"Carboxylic acids",
"Functional groups",
"Organic compounds",
"Antibiotics",
"Biocides",
"Organic compound stubs",
"Organic chemistry stubs"
] |
70,867,509 | https://en.wikipedia.org/wiki/Bimodal%20atomic%20force%20microscopy | Bimodal Atomic Force Microscopy (bimodal AFM) is an advanced atomic force microscopy technique characterized by generating high-spatial resolution maps of material properties. Topography, deformation, elastic modulus, viscosity coefficient or magnetic field maps might be generated. Bimodal AFM is based on the simultaneous excitation and detection of two eigenmodes (resonances) of a force microscope microcantilever.
History
Numerical and theoretical considerations prompted the development of bimodal AFM. The method was initially thought to enhance topographic contrast in air environments. Three subsequent advances such as the capability to detect non-topography properties such electrostatic and magnetic interactions; imaging in liquid and ultra-high vacuum and its genuine quantitative features set the stage for further developments and applications.
Principles of Bimodal AFM
The interaction of the tip with the sample modifies the amplitudes, phase shifts and frequency resonances of the excited modes. Those changes are detected and processed by the feedback of the instrument. Several features make bimodal AFM a very powerful surface characterization method at the nanoscale. (i) Resolution. Atomic, molecular or nanoscale spatial resolution was demonstrated. (ii) Simultaneity. Maps of different properties are generated at the same time. (iii) Efficiency. A maximum number of four data points per pixel are needed to generate material property maps. (iv) Speed. Analytical solutions link observables with material properties.
Configurations
In AFM, feedback loops control the operation of the microscope by keeping a fixed value a parameter of the tip's oscillation. If the main feedback loop operates with the amplitude, the AFM mode is called amplitude modulation (AM). If it operates with the frequency shift, the AFM mode is called frequency modulation (FM). Bimodal AFM might be operated with several feedback loops. This gives rise to a variety of bimodal configurations. The configurations are termed AM-open loop, AM-FM, FM-FM. For example, bimodal AM-FM means that the first mode is operated with an amplitude modulation loop while the 2nd mode is operated with a frequency modulation loop. The configurations might not be equivalent in terms of sensitivity, signal-to-noise ratio or complexity.
Let's consider the AM-FM configuration. The first mode is excited to reach free amplitude (no interaction) and the changes of its amplitude and phase shift are tracked by a lock-in amplifier. The main feedback loop keeps constant the amplitude, at a certain set-point by modifying the tip vertical position (AM). In a nanomechanical mapping experiment, must be kept below 90°, i.e., the AFM is operated in the repulsive regime. At the same time, an FM loop acts on the second eigenmode. A phase-lock-loop regulates the excitation frequency by keeping the phase shift of the second mode at 90°. An additional feedback loop might be used to maintain the amplitude constant.
Theory
The theory of bimodal AFM operation encompasses several aspects. Among them, the approximations to express the Euler-Bernoulli equation of a continuous cantilever beam in terms of the equations of the excited modes, the type of interaction forces acting on the tip, the theory of demodulation methods or the introduction of finite-size effects.
In a nutshell, the tip displacement in AFM is approximated by a point-mass model,
where , , , , , and are, respectively, the driving frequency, the free resonant frequency, the quality factor, the stiffness, the driving force of the i-th mode, and the tip–sample interaction force. In bimodal AFM, the vertical motion of the tip (deflection) has two components, one for each mode,
with , , , as the static, the first, and the second mode deflections; , and are, respectively, the amplitude, frequency and phase shift of mode i.
The theory that transforms bimodal AFM observables into material properties is based on applying the virial and energy dissipation theorems to the equations of motion of the excited modes. The following equations were derived
where is a time where the oscillation of both modes are periodic; the quality factor of mode i. Bimodal AFM operation might be involve any pair of eigenmodes. However, experiments are commonly performed by exciting the first two eigenmodes.
The theory of bimodal AFM provides analytical expressions to link material properties with microscope observables. For example, for a paraboloid probe (radius ) and a tip-sample force given by the linear viscoelastic Kelvin-Voigt model, the effective elastic modulus of the sample, viscous coefficient of compressibility , loss tangent or retardation time are expressed by
For an elastic material, the second term of equation to calculate disappears because which gives . The elastic modulus is obtained from the equation above. Other analytical expressions were proposed for the determination of the Hamaker constant and the magnetic parameters of a ferromagnetic sample.
Applications
Bimodal AFM is applied to characterize a large variety of surfaces and interfaces. Some applications exploit the sensitivity of bimodal observables to enhance spatial resolution. However, the full capabilities of bimodal AFM are shown in the generation of quantitative maps of material properties. The section is divided in terms of the achieved spatial resolution, atomic-scale or nanoscale.
Atomic and molecular-scale resolution
Atomic-scale imaging of graphene, semiconductor surfaces and adsorbed organic molecules were obtained in ultra high-vacuum. Angstrom-resolution images of hydration layers formed on proteins and Young's modulus map of a metal-organic frame work, purple membrane and a lipid bilayer were reported in aqueous solutions.
Material property applications
Bimodal AFM is widely used to provide high-spatial resolution maps of material properties, in particular, mechanical properties. Elastic and/or viscoelastic property maps of polymers, DNA, proteins, protein fibers, lipids or 2D materials were generated. Non-mechanical properties and interactions including crystal magnetic garnets, electrostatic strain, superparamagnetic particles and high-density disks were also mapped. Quantitative property mapping requires the calibration of the force constants of the excited modes.
References
Scanning probe microscopy
Intermolecular forces
Scientific techniques | Bimodal atomic force microscopy | [
"Chemistry",
"Materials_science",
"Engineering"
] | 1,326 | [
"Molecular physics",
"Materials science",
"Intermolecular forces",
"Scanning probe microscopy",
"Microscopy",
"Nanotechnology"
] |
70,868,136 | https://en.wikipedia.org/wiki/Neoechinodiscus%20kozhevnikovii | Neoechinodiscus kozhevnikovii is a species of lichenicolous (lichen-eating) fungus in the order Helotiales. It is known to occur in Russia, Austria, and Switzerland, where it grows parasitically on lichens in genus Cetraria.
Taxonomy
The fungus was formally described as new to science in 2009 by lichenologist Mikhail Zhurbenko, who placed it in the genus Echinodiscus. The type specimen was collected by the author at the head of Kaskasnyunjok Creek (in the Khibiny Mountains, Murmansk Oblast); there, at an altitude of , the fungus was found growing on Cetraria islandica, which itself was growing on lichen tundra. The species epithet kozhevnikovii honours the late Dr. Yurii Kozhevnikov, a friend of the author and a "devoted explorer of Arctic wildlife".
The taxon was transferred to the genus Neoechinodiscus after it was discovered that Echinodiscus was an illegitimate homonym that had already been used for other taxa. The replacement name Neoechinodiscus was proposed by Rubén Sierra and Eduardo Molinari-Novoa in 2020.
Description
Neoechinodiscus kozhevnikovii produces plate-like (discoid), sessile apothecia that lack a distinct margin and measure 50–150 μm in diameter and about 50 μm in height. The asci are club-shaped (clavate) with a distinct stalk, contains eight spores, and typically measure 40–50 by 9–13 μm. Ascospores are narrowly oblong in shape, hyaline, lack any septa, often contain oil droplets (guttules), and measure 10–12 by 2.5–3.5 μm.
Habitat and distribution
Originally described from mountain and arctic tundras of Russia, Neoechinodiscus kozhevnikovii has also been recorded from the Lepontine Alps of Switzerland, and the Tyrol of Austria. Known hosts for the fungus are Cetraria islandica and Cetraria laevigata.
References
Helotiales
Fungi described in 2009
Lichenicolous fungi
Fungi of the Arctic
Fungus species | Neoechinodiscus kozhevnikovii | [
"Biology"
] | 468 | [
"Fungi",
"Fungus species"
] |
70,868,327 | https://en.wikipedia.org/wiki/12%20Trianguli | 12 Trianguli is a solitary star located in the northern constellation Triangulum, with an apparent magnitude of 5.37, making it faintly visible to the naked eye under ideal conditions. The star is situated 160 light years away but is approaching with a heliocentric radial velocity of . It is calculated to be about old with a stellar classification of F0 III, making it an F-type giant. It has 1.6 times the mass of the Sun and shines at 14 times the luminosity of the Sun from its photosphere at an effective temperature of .
Together with ι Trianguli and 10 Trianguli, it forms part of the obsolete Triangulum Minus.
References
F-type giants
Triangulum
Trianguli, 12
15257
11486
0717
Durchmusterung objects | 12 Trianguli | [
"Astronomy"
] | 167 | [
"Triangulum",
"Constellations"
] |
70,869,031 | https://en.wikipedia.org/wiki/Kappa%20Octantis | Kappa Octantis, Latinized from κ Octantis, is a solitary star in the southern circumpolar constellation Octans. It has an apparent magnitude of 5.55, making it visible to the naked eye under ideal conditions. The object is located at a distance of 285 light years but is approaching the Solar System with a heliocentric radial velocity of .
Kappa Octanits is an Am star, making it difficult to classify. It has been given a stellar classification of A2 mA5-A8, indicating that it is an A2 star with the metallic lines of an A5-A8 star. At present it has 2.07 times the mass of the Sun and 2.75 its radius. It shines at a luminosity of about from its photosphere at an effective temperature of 7,943 K, giving it a white glow. Kappa Octantis is said to be around 350 million years old.
References
Octans
Am stars
A-type stars
Octantis, Kappa
Octantis, 18
117374
066753
5084
PD-85 384 | Kappa Octantis | [
"Astronomy"
] | 227 | [
"Octans",
"Constellations"
] |
70,870,585 | https://en.wikipedia.org/wiki/Endococcus%20hafellneri | Endococcus hafellneri is a species of lichenicolous (lichen-eating) fungus in the family Verrucariaceae. It is found in North Asia and the Russian Far East, Estonia, and Japan, where it grows on the lobes of the lichens Flavocetraria cucullata and Cetraria islandica.
Taxonomy
The fungus was formally described as a new species in 2009 by Mikhail Zhurbenko. He placed the species provisionally in the genus Stigmidium, but unlike all other species of that genus, the new fungus has coloured (brown) ascospores. The species epithet honours German lichenologist Josef Hafellner, "in recognition of his important contribution to the knowledge of lichenicolous fungi".
In 2019, Zhurbenko transferred the taxon to the Endococcus. Having had the opportunity to collect and observe more specimens, he noted the constancy of the coloured spores, and concluded that the traits of genus Endococcus are better aligned with the characteristics of the fungus.
Description
Endococcus hafellneri produces ascomata with a perithecioid morphology–more or less rounded, with an ostiole. They are black and shiny and protrude slightly from the surface of the host lichen, measuring up to 50 μm in diameter. Infection by the fungus causes grey and sometimes perforated patches in the host lichen up to across, sometimes with a dark greyish-brown rim around the margin of the patch.
Habitat and distribution
In Asian Russia, Endococcus hafellneri has been recorded from Buryatia, Sakha, the Magadan Oblast, and the Caucasus. It was reported from Kihnu island (Estonia) in 2015, and from Hokkaido, Japan, in 2019. Known hosts for the fungus are Flavocetraria cucullata and Cetraria islandica.
References
Verrucariales
Fungi described in 2009
Fungi of Asia
Fungi of Europe
Lichenicolous fungi
Taxa named by Mikhail Petrovich Zhurbenko
Fungus species | Endococcus hafellneri | [
"Biology"
] | 429 | [
"Fungi",
"Fungus species"
] |
70,871,102 | https://en.wikipedia.org/wiki/Thiosarin | Thiosarin, sulfursarin or GBS, is the organophosphorus compound analogous to sarin. It differs structurally in that sulfur replaces the oxygen of the P=O bond. It is an extremely toxic substance related to G-agents.
Characteristics
For thiosarin, unlike sarin, the literature contains little information. It is reported as a colorless liquid with a characteristic organosulfur odor when pure. It is estimated to have a boiling point of 144-167 °C. It is a more nonpolar compound, with a solubility in water of 7 g/L. Thiosarin probably belongs to the IVA compound series, leaving it much less volatile than sarin. It has a greater persistence in the environment than sarin.
Absorption frequencies of sarin derivatives showed that the frequency of stretching of the P-F and P=S bond of thiosarin is lower than that of its oxygenated analogue.
CW history and candidate
Its toxicity was discovered in the 1970s by Friedrick Wilhelm Hoffmann and Ray King Irino. They were responsible for synthesizing and analyzing a series of sulfur G-agent compounds. The open literature reports that the compound has been cataloged as GS, but this statement is incorrect, it belongs to EA-1246. GS agents are a series of G compounds. GBS is generally lower than sarin. The little open military literature may be due to the low toxicity of this series of compounds.
The possibility of a chemical warfare agent candidate was raised when Bogomazov and his colleagues discovered that thiosarin had the ability to break through military gas mask filters, where it would then be converted to its analogue. An investigation by Vil Mirzayanov refuted these results.
Thiosarin is used as a precursor to sarin.
Synthesis
The preparation route is quite similar to that of sarin. The synthesis routes of thiosarin are manifold.
Regardless of the synthesis route chosen, the final reaction is usually the reaction of isopropyl methylthiophosphonochloridate with fluorides.
Reactions
Thiosarin has a tendency to convert to the all oxygen analogue by divers mechanisms.. In anhydrous medium, thiosarin is oxidized to form GB.
In the controlated aqueous medium, without the presence of oxygen, the tendency is to evolve hydrogen sulfide.
Sarin-S
Along with the discovery of the high toxicity of this series of compounds, Hoffmann discovered that the S-alkyl isomers, unlike the alkyl alkylphosphonothiol compounds, were less toxic than the G(S) agents.
References
Nerve agents
G-series nerve agents
Acetylcholinesterase inhibitors
Isopropyl esters
Methylphosphonofluoridates
Sulfur compounds | Thiosarin | [
"Chemistry"
] | 579 | [
"Nerve agents",
"Chemical weapons"
] |
70,871,382 | https://en.wikipedia.org/wiki/HD%20200044 | HD 200044 (HR 8044) is a solitary star in the equatorial constellation Delphinus. It has an apparent magnitude of 5.7, allowing it to be faintly seen with the naked eye. The object is located 598 light years away, but is approaching the Solar System with a heliocentric radial velocity of .
HD 200044 has a spectral classification of M3 IIIab, indicating that its an ageing red giant. It is currently on the asymptotic giant branch and is fusing hydrogen and helium in shells around an inert carbon core. As a consequence, it has expanded to 58 times the radius of the Sun and is now radiating with a luminosity over 500 times greater than that of the Sun. HD 200044's large size and high luminosity yield an effective temperature of 3,707 K, giving it a red glow. HD 200044 is suspected to be a variable star with an amplitude of 0.05 magnitudes.
There is a 10th magnitude optical companion separated away and at a position angle of as of 2014. However, the separation is increasing due to HD 200044's high proper motion.
References
Delphinus
M-type giants
Asymptotic-giant-branch stars
200044
103675
8044
BD+18 4675 | HD 200044 | [
"Astronomy"
] | 265 | [
"Delphinus",
"Constellations"
] |
70,872,217 | https://en.wikipedia.org/wiki/Graphium%20samogiticum | Graphium samogiticum is a little-known species of lichenicolous (lichen-eating) fungus in the family Microascaceae. It is found in Lithuania, where it parasitises two lichen species that inhabit abandoned gravel pits.
Taxonomy
The fungus was formally described as a new species in 2006 by Jurga Motiejūnaitė and Vagn Alstrup. The type specimen was collected in Žemaitija National Park (Plungė District); there, in an abandoned gravel pit in Žalnierkalnis, the fungus was found growing on the thallus of the crustose lichen Verrucaria bryoctona, which itself was growing on gravelly soil. The species epithet refers to the type locality: samogiticum is formed from the Latin name for Žemaitija (Samogitia).
Description
Graphium samogiticum is an anamorphic fungus, meaning that its sexual cycle has not been observed, or does not exist–only asexual and vegetative phases are known. The conidiophores made by the fungus are grouped together in black synnemata that are 80–120 μm high and 25 μm thick. The thick-walled conidia are a pale grey-brown colour with dimensions of 6.5–8 by 3–4 μm. A morphologically similar species is Graphium aphthosae, which grows on Peltigera lichens.
Known hosts for the fungus are Sarcosagium campestre and Verrucaria bryoctona. Of the twenty six known lichenicolous fungi that have a strict host preference on genus Verrucaria, Graphium samogiticum is the only anamorphic fungus. Little is known about the ecology and distribution of Graphium samogiticum; the lichens it was parasitising are inhabitants of a little-studied habitat the authors call a "pioneer epigeal community". They suggest it may have a more widespread European distribution.
References
Microascales
Fungi described in 2006
Lichenicolous fungi
Fungus species | Graphium samogiticum | [
"Biology"
] | 431 | [
"Fungi",
"Fungus species"
] |
70,872,240 | https://en.wikipedia.org/wiki/Constance%20Tom%20Noguchi | Constance Tom Noguchi (born December 8, 1948) is a research physicist, Chief of the Molecular Cell Biology Section, and Dean of the Foundation for Advanced Education in the Sciences (FAES) Graduate School at the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) of the National Institutes of Health (NIH).
Noguchi studies the underlying genetics, metabolism, and treatment of sickle cell disease and of erythropoietin and its effects on metabolism.
Noguchi has published over 250 scientific articles with over 9491 citations.
Noguchi is one of 21 Asian Americans profiled in Asian American Biographies (1994)
for their contributions to the arts, politics, and science. She is the subject of Scientist and puzzle solver, Constance Tom Noguchi (1985).
Early life and education
Constance Tom was born on December 8, 1948, in Guangzhou (Canton, China) to James Tom and Irene Cheung. Her father was a Chinese-American, and the family soon returned to the United States. Constance Tom grew up in San Francisco, California and married Philip David Noguchi in 1969.
Noguchi studied in mathematics and physics at the University of California, Berkeley, receiving her B.Sc. in 1970. She then attended George Washington University where she received her PhD in theoretical nuclear physics in 1975.
Career
Noguchi joined the National Institutes of Health (NIH) in 1975, as a fellow with Alan N. Schechter at the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Noguchi became a research physicist at NIDDK in 1985.
She became Chief of the Molecular Cell Biology Section of NIDDK in 1994, and Dean of the NIH's Foundation for Advanced Education in the Sciences (FAES) in 1999.
Noguchi studies the underlying genetics, metabolism, and treatment of sickle cell disease, in particular sickle hemoglobin polymerization.
Noguchi has developed methods to measure the severity of sickle cell disease, a disease that affects newborns. By measuring oxygen saturation, total hemoglobin concentration, and hemoglobin composition, she calculates the polymer content of sickle cells. Polymer content can be used to choose treatments and assess their effectiveness.
Noguchi has studied hydroxyurea and hemoglobin, showing that hydroxyurea can increase a form of fetal hemoglobin in sickle cell disease.
Noguchi has also shown that polymer formation correlates with mean corpuscular hemoglobin concentration (MCHC), and will vary from patient to patient.
In 1991, Noguchi isolated and cloned the human erythropoietin receptor gene.
Erythropoietin is an essential hormone for red blood cell production that is produced by the kidneys and binds to the erythropoietin receptor (EpoR). When a person's erythrocyte count is higher than the normal range for their sex, the disease state erythrocytosis can occur. Erythrocytosis has been linked to a variety of EpoR gene mutations.
Erythropoietin regulation is involved in metabolism in a number of ways, including oxygen delivery, maintenance of white adipose tissue, and the maintenance of metabolic homeostasis.
Awards and honors
1995, APIAAC outstanding achievement award, National Institutes of Health
2001, Mentoring Award, Association for Women in Science, Bethesda
References
Living people
People from Guangzhou
Women biologists
University of California, Berkeley alumni
George Washington University alumni
Molecular biologists
1948 births
National Institutes of Health people
21st-century American physicists | Constance Tom Noguchi | [
"Chemistry"
] | 745 | [
"Molecular biologists",
"Biochemists",
"Molecular biology"
] |
70,872,424 | https://en.wikipedia.org/wiki/14%20Trianguli | 14 Trianguli (14 Tri), also known as HD 15656, is a spectroscopic binary located in the northern constellation Triangulum. It has an apparent magnitude of 5.14, making it faintly visible to the naked eye in ideal conditions. Gaia DR3 parallax measurements place the system 433 light years away, and it is currently approaching the Solar System with a heliocentric radial velocity of . At its current distance, 14 Tri's brightness is diminished by 0.21 magnitude due to interstellar dust. It has an absolute magnitude of −0.46.
The visible component is an evolved red giant with a stellar classification of K5 III. It has 1.85 times the mass of the Sun, but it has expanded to 39 times its girth. It radiates 325 times the luminosity of the Sun from its photosphere at an effective temperature of , giving it an orangish-red hue. 14 Tri is slightly metal-deficient with [Fe/H] = −0.16, and spins modestly with a projected rotational velocity of . This is a single-lined spectroscopic binary that completes an eccentric orbit within 17 years. The secondary star has not been detected visually or in the spectrum and is expected to be a low-mass red dwarf or white dwarf. 14 Tri may be part of the Wolf 630 moving group.
References
Further reading
K-type giants
Triangulum
Trianguli, 14
015656
011784
0736
BD+35 00497 | 14 Trianguli | [
"Astronomy"
] | 317 | [
"Triangulum",
"Constellations"
] |
70,873,435 | https://en.wikipedia.org/wiki/Axinelline%20A | Axinelline A is a COX-2 inhibitor with the molecular formula C12H15NO6 which is produced by the bacterium Streptomyces axinellae.
References
COX-2 inhibitors
Ethyl esters
Catechols
Benzamides
Triols | Axinelline A | [
"Chemistry"
] | 56 | [
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
70,873,478 | https://en.wikipedia.org/wiki/Blastmycin | Blastmycin is an antibiotic with the molecular formula C26H36N2O9 which is produced by the bacterium Streptomyces blastmyceticus.
References
Antibiotics
Anilides
Lactones
Benzamides
Formamides | Blastmycin | [
"Chemistry",
"Biology"
] | 50 | [
"Biotechnology products",
"Organic compounds",
"Antibiotics",
"Biocides",
"Organic compound stubs",
"Organic chemistry stubs"
] |
70,873,538 | https://en.wikipedia.org/wiki/Sieve%20of%20Pritchard | In mathematics, the sieve of Pritchard is an algorithm for finding all prime numbers up to a specified bound.
Like the ancient sieve of Eratosthenes, it has a simple conceptual basis in number theory.
It is especially suited to quick hand computation for small bounds.
Whereas the sieve of Eratosthenes marks off each non-prime for each of its prime factors, the sieve of Pritchard avoids considering almost all non-prime numbers by building progressively larger wheels, which represent the pattern of numbers not divisible by any of the primes processed thus far.
It thereby achieves a better asymptotic complexity, and was the first sieve with a running time sublinear in the specified bound.
Its asymptotic running-time has not been improved on, and it deletes fewer composites than any other known sieve.
It was created in 1979 by Paul Pritchard.
Since Pritchard has created a number of other sieve algorithms for finding prime numbers, the sieve of Pritchard is sometimes singled out by being called the wheel sieve (by Pritchard himself) or the dynamic wheel sieve.
Overview
A prime number is a natural number that has no natural number divisors other than the number 1 and itself.
To find all the prime numbers less than or equal to a given integer , a sieve algorithm examines a set of candidates in the range , and eliminates those that are not prime, leaving the primes at the end. The sieve of Eratosthenes examines all of the range, first removing all multiples of the first prime 2, then of the next prime 3, and so on. The sieve of Pritchard instead examines a subset of the range consisting of numbers that occur on successive wheels, which represent the pattern of numbers left after each successive prime is processed by the sieve of Eratosthenes.
For , the th wheel represents this pattern. It is the set of numbers between 1 and the product of the first prime numbers that are not divisible by any of these prime numbers (and is said to have an associated length ). This is because adding to a number does not change whether it is divisible by one of the first prime numbers, since the remainder on division by any one of these primes is unchanged.
So with length represents the pattern of odd numbers; with length represents the pattern of numbers not divisible by 2 or 3; etc. Wheels are so-called because can be usefully visualized as a circle of circumference with its members marked at their corresponding distances from an origin. Then rolling the wheel along the number line marks points corresponding to successive numbers not divisible by one of the first prime numbers. The animation shows being rolled up to 30.
It is useful to define for to be the result of rolling up to . Then the animation generates . Note that up to , this consists only of 1 and the primes between 5 and 25.
The sieve of Pritchard is derived from the observation that this holds generally: for all , the values in are 1 and the primes between and . It even holds for , where the wheel has length 1 and contains just 1 (representing all the natural numbers). So the sieve of Pritchard starts with the trivial wheel and builds successive wheels until the square of the wheel's first member after 1 is at least . Wheels grow very quickly, but only their values up to are needed and generated.
It remains to find a method for generating the next wheel. Note in the animation that can be obtained by rolling up to 30 and then removing 5 times each member of .This also holds generally: for all , . Rolling past just adds values to , so the current wheel is first extended by getting each successive member starting with , adding to it, and inserting the result in the set. Then the multiples of are deleted. Care must be taken to avoid a number being deleted that itself needs to be multiplied by . The sieve of Pritchard as originally presented does so by first skipping past successive members until finding the maximum one needed, and then doing the deletions in reverse order by working back through the set. This is the method used in the first animation above. A simpler approach is just to gather the multiples of in a list, and then delete them. Another approach is given by Gries and Misra.
If the main loop terminates with a wheel whose length is less than , it is extended up to to generate the remaining primes.
The algorithm, for finding all primes up to , is therefore as follows:
Start with a set and representing wheel 0, and prime .
As long as , do the following:
if , then
extend by repeatedly getting successive members of starting with 1 and inserting into as long as it does not exceed or ;
increase to the minimum of and .
repeatedly delete times each member of by first finding the largest and then working backwards.
note the prime , then set to the next member of after 1 (or 3 if was 2).
if , then extend to by repeatedly getting successive members of starting with 1 and inserting into as long as it does not exceed ;
On termination, the rest of the primes up to are the members of after 1.
Example
To find all the prime numbers less than or equal to 150, proceed as follows.
Start with wheel 0 with length 1, representing all natural numbers 1, 2, 3...:
1
The first number after 1 for wheel 0 (when rolled) is 2; note it as a prime. Now form wheel 1 with length 21 = 2 by first extending wheel 0 up to 2 and then deleting 2 times each number in wheel 0, to get:
1
The first number after 1 for wheel 1 (when rolled) is 3; note it as a prime. Now form wheel 2 with length 32 = 6 by first extending wheel 1 up to 6 and then deleting 3 times each number in wheel 1, to get
1 5
The first number after 1 for wheel 2 is 5; note it as a prime. Now form wheel 3 with length 56 = 30 by first extending wheel 2 up to 30 and then deleting 5 times each number in wheel 2 (in reverse order!), to get
1 7 11 13 17 19 23 29
The first number after 1 for wheel 3 is 7; note it as a prime. Now wheel 4 has length 730 = 210, so we only extend wheel 3 up to our limit 150. (No further extending will be done now that the limit has been reached.) We then delete 7 times each number in wheel 3 until we exceed our limit 150, to get the elements in wheel 4 up to 150:
1 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71 73 79 83 89 97 101 103 107 109 113 121 127 131 137 139 143 149
The first number after 1 for this partial wheel 4 is 11; note it as a prime. Since we have finished with rolling, we delete 11 times each number in the partial wheel 4 until we exceed our limit 150, to get the elements in wheel 5 up to 150:
1 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71 73 79 83 89 97 101 103 107 109 113 127 131 137 139 149
The first number after 1 for this partial wheel 5 is 13. Since 13 squared is at least our limit 150, we stop. The remaining numbers (other than 1) are the rest of the primes up to our limit 150.
Just 8 composite numbers are removed, once each. The rest of the numbers considered (other than 1) are prime. In comparison, the natural version of Eratosthenes sieve (stopping at the same point) removes composite numbers 184 times.
Pseudocode
The sieve of Pritchard can be expressed in pseudocode, as follows:
algorithm Sieve of Pritchard is
input: an integer N >= 2.
output: the set of prime numbers in {1,2,...,N}.
let W and Pr be sets of integer values, and all other variables integer values.
k, W, length, p, Pr := 1, {1}, 2, 3, {2};
{invariant: p = pk+1 and W = Wk {1,2,...,N} and length = minimum of Pk,N and Pr = the primes up to pk}
while p2 <= N do
if (length < N) then
Extend W,length to minimum of p*length,N;
Delete multiples of p from W;
Insert p into Pr;
k, p := k+1, next(W, 1)
if (length < N) then
Extend W,length to N;
return Pr W - {1};
where is the next value in the ordered set after .
procedure Extend W,length to n is
{in: W = Wk and length = Pk and n > length}
{out: W = Wkn and length = n}
integer w, x;
w, x := 1, length+1;
while x <= n do
Insert x into W;
w := next(W,w);
x := length + w;
length := n;
procedure Delete multiples of p from W,length is
integer w;
w := p;
while p*w <= length do
w := next(W,w);
while w > 1 do
w := prev(W,w);
Remove p*w from W;
where is the previous value in the ordered set before . The algorithm can be initialized with instead of at the minor complication of making a special case when .
This abstract algorithm uses ordered sets supporting the operations of insertion of a value greater than the maximum, deletion of a member, getting the next value after a member, and getting the previous value before a member. Using one of Mertens' theorems (the third) it can be shown to use of these operations and additions and multiplications.
Implementation
An array-based doubly-linked list can be used to implement the ordered set , with storing and storing . This permits each abstract operation to be implemented in a small number of operations. (The array can also be used to store the set "for free".) Therefore the time complexity of the sieve of Pritchard to calculate the primes up to in the random access machine model is operations on words of size . Pritchard also shows how multiplications can be eliminated by using very small multiplication tables, so the bit complexity is bit operations.
In the same model, the space complexity is words, i.e., bits. The sieve of Eratosthenes requires only 1 bit for each candidate in the range 2 through , so its space complexity is lower at bits. Note that space needed for the primes is not counted, since they can printed or written to external storage as they are found. Pritchard presented a variant of his sieve that requires only bits without compromising the sublinear time complexity, making it asymptotically superior to the natural version of the sieve of Eratostheses in both time and space.
However, the sieve of Eratostheses can be optimized to require much less memory by operating on successive segments of the natural numbers. Its space complexity can be reduced to bits without increasing its time complexity. This means that in practice it can be used for much larger limits than would otherwise fit in memory, and also take advantage of fast cache memory. For maximum speed, it is also optimized using a small wheel to avoid sieving with the first few primes (although this does not change its asymptotic time complexity). Therefore the sieve of Pritchard is not competitive as a practical sieve over sufficiently large ranges.
Geometric model
At the heart of the sieve of Pritchard is an algorithm for building successive wheels. It has a simple geometric model as follows:
Start with a circle of circumference 1 with a mark at 1.
To generate the next wheel:
Go around the wheel and find (the distance to) the first mark after 1; call it .
Create a new circle with times the circumference of the current wheel.
Roll the current wheel around the new circle, marking it where a mark touches it.
Magnify the current wheel by and remove the marks that coincide.
For the first 2 iterations it is necessary to continue round the circle until 1 is reached again.
The first circle represents , and successive circles represent wheels . The animation on the right shows this model in action up to .
It is apparent from the model that wheels are symmetric. This is because is not divisible by one of the first primes if and only if is not so divisible. It is possible to exploit this to avoid processing some composites, but at the cost of a more complex algorithm.
Related sieves
Once the wheel in the sieve of Pritchard reaches its maximum size, the remaining operations are equivalent to those performed by Euler's sieve.
The sieve of Pritchard is unique in conflating the set of prime candidates with a dynamic wheel used to speed up the sifting process. But a separate static wheel (as frequently used to speed up the sieve of Eratosthenes) can give an speedup to the latter, or to linear sieves, provided it is large enough (as a function of ). Examples are the use of the largest wheel of length not exceeding to get a version of the sieve of Eratosthenes that takes additions and requires only bits, and the speedup of the naturally linear sieve of Atkin to get a sublinear optimized version.
Bengalloun found a linear smoothly incremental sieve, i.e., one that (in theory) can run indefinitely and takes a bounded number of operations to increment the current bound . He also showed how to make it sublinear by adapting the sieve of Pritchard to incrementally build the next dynamic wheel while the current one is being used. Pritchard showed how to avoid multiplications, thereby obtaining the same asymptotic bit-complexity as the sieve of Pritchard.
Runciman provides a functional algorithm inspired by the sieve of Pritchard.
See also
Sieve of Eratosthenes
Sieve of Atkin
Sieve theory
Wheel factorization
References
Primality tests
Articles with example pseudocode
Sieve theory
Algorithms | Sieve of Pritchard | [
"Mathematics"
] | 3,006 | [
"Sieve theory",
"Applied mathematics",
"Algorithms",
"Mathematical logic",
"Combinatorics"
] |
70,875,049 | https://en.wikipedia.org/wiki/Kyoung-Shin%20Choi | Kyoung-Shin Choi () is a professor of chemistry at the University of Wisconsin-Madison. Choi's research focuses on the electrochemical synthesis of electrode materials, for use in electrochemical and photoelectrochemical devices.
Early life and education
Choi studied piano at Yewon Middle School, Korea's first middle school dedicated to the arts. In high school, Choi liked Chemistry and Physics classes tremendously and decided to become a scientist. Choi attended college at Seoul National University in South Korea, earning her B.S. (major in Food and Nutrition and minor in Chemistry) in 1993 and M.S. in 1995. She worked with Jin-Ho Choy on the crystal structure, pressure-induced phase transitions, and magnetism of chromium-niobium oxide materials that adopt the double perovskite structure.
For her doctoral study, Choi came to the United States in 1995. She worked at Michigan State University in the laboratory of Mercouri G. Kanatzidis, earning her Ph.D. in chemistry in 2000. Her graduate work focused on the synthesis of various solid state antimony and bismuth-containing chalcogenides using the "molten polychalcogenide salt method."
Choi then conducted postdoctoral studies from 2000 to 2002 at the University of California, Santa Barbara with Galen D. Stucky and Eric W. McFarland. Her postdoctoral research concerned the electrochemical synthesis of nanostructured thin films.
Independent career
Choi began her independent career at Purdue University as an assistant professor in 2002, and was later promoted to associate professor. She was a visiting scholar at the National Renewable Energy Laboratory in 2008. In 2012, she moved to University of Wisconsin-Madison as a full professor of chemistry.
Choi has served as an associate editor of the journal Chemistry of Materials since 2014.
Research
The Choi research group studies electrodes and catalysts for use in photoelectrochemical and electrochemical applications. Earlier work in the group has included the crystallization of cuprous oxide in various morphologies, in which the authors utilized electrochemistry to control the crystallization process and resultant crystal morphologies.
The Choi group has extensively studied bismuth vanadate, a photoanode for light-driven water splitting. This material suffers from facile bulk electron-hole recombination, but by combining the bismuth vanadate catalyst with oxygen-evolution catalysts such as FeOOH and NiOOH, Choi and coworkers were able to minimize this deleterious process and achieve higher catalytic efficiencies. The Choi group has also studied the stability of the bismuth vanadate catalyst, as well as the effects of surface composition on the interfacial energetics of photoelectrochemical catalysis.
In one report, Choi and coworkers developed a photoelectrochemical cell (PEC), a device that can split water into hydrogen and oxygen given inputs of light and electricity. PECs are promising devices for hydrogen production, for use in a hydrogen economy. However, the anodic reaction, the oxygen evolution reaction (OER), is slow and limits the overall process. To sidestep this problem, Choi and coworkers paired the hydrogen evolution reaction (HER) with oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA). This allows them to generate FDCA, a valuable commodity chemical used in plastic production, from HMF, which can be derived from cellulose.
Awards
Source:
2006 Alfred P. Sloan Research Fellowship, Alfred P. Sloan Foundation
2006 ACS PROGRESS/Dreyfus Lectureship award, American Chemical Society
2007 ACS-ExxonMobil Solid State Chemistry Faculty Fellowship
2008 Purdue College of Science Outstanding Undergraduate Teaching Award by an Assistant Professor
2010 Iota Sigma Pi Agnes Fay Morgan Research Award
2011 University Faculty Scholar, Purdue University
2011 Volume Organizer of Materials Research Society Bulletin
2011 Chair, ACS-Division of Inorganic Chemistry, Solid State Subdivision
2013 Kavli Frontiers of Science Fellow (National Academy of Sciences)
2014 Chair, Gordon Research Conference-Electrodeposition
2014 Speaker for the Stanford Distinguished Women in Science Colloquia Series
2014 University Housing Honored Instructor
2015 Camille and Henry Dreyfus Environmental Chemistry Mentor
2015 Wisconsin Alumni Research Foundation (WARF) Innovation Award
2016 UW-Madison Villas Associate Award
2017 MIT Student-Invited Inorganic Seminar Speaker
2018 Student Selected ECS Speaker (Indiana University)
2018 Michigan State University Alumni Lectureship Award
2019 UW-Madison Villas Faculty Mid-Career Investigator Award
2023 American Association for the Advancement of Science Fellow
2023 Ho-Am Prize in Science Chemistry and Life Sciences
2024 American Academy of Arts and Sciences Fellow
References
External links
American women chemists
American women academics
Seoul National University alumni
Michigan State University alumni
Purdue University faculty
University of Wisconsin–Madison faculty
21st-century American women
American people of Korean descent
Electrochemists
Inorganic chemists
Year of birth missing (living people)
Living people | Kyoung-Shin Choi | [
"Chemistry"
] | 1,026 | [
"Electrochemistry",
"Inorganic chemists",
"Electrochemists"
] |
70,875,524 | https://en.wikipedia.org/wiki/Underwater%20survey | An underwater survey is a survey performed in an underwater environment or conducted remotely on an underwater object or region. Survey can have several meanings. The word originates in Medieval Latin with meanings of looking over and detailed study of a subject. One meaning is the accurate measurement of a geographical region, usually with the intention of plotting the positions of features as a scale map of the region. This meaning is often used in scientific contexts, and also in civil engineering and mineral extraction. Another meaning, often used in a civil, structural, or marine engineering context, is the inspection of a structure or vessel to compare actual condition with the specified nominal condition, usually with the purpose of reporting on the actual condition and compliance with, or deviations from, the nominal condition, for quality control, damage assessment, valuation, insurance, maintenance, and similar purposes. In other contexts it can mean inspection of a region to establish presence and distribution of specified content, such as living organisms, either to establish a baseline, or to compare with a baseline.
These types of survey may be done in or of the underwater environment, in which case they may be referred to as underwater surveys, which may include bathymetric, hydrographic, and geological surveys, archaeological surveys, ecological surveys, and structural or vessel safety surveys. In some cases they can be done by remote sensing, using a variety of tools, and sometimes by direct human intervention, usually by a professional diver. Underwater surveys are an essential part of the planning, and often of quality control and monitoring, of underwater construction, dredging, mineral extraction, ecological monitoring, and archaeological investigations. They are often required as part of an ecological impact study.
Types
The types of underwater survey include, but are not necessarily restricted to, archeological, bathymetric and hydrographic, ecological, geological, and construction site surveys, and inspection surveys of marine and coastal structures and vessels afloat. A survey of the vessel structural condition and the adjacent site and hydrographic conditions would also be done when assessing proposed marine salvage operations.
Archaeological surveys
Archaeological surveys of underwater sites have traditionally been done by divers, but at sites where the depth is too great, sonar surveys have been done from surface and submersible vehicles, and photomosaic techniques have been done using ROUVs. Traditional methods include direct measurement from a baseline or grid set up at the site, and triangulation by direct measurement from marks of known position installed at the site, in the same way these would be used at a terrestrial site. Accuracy may be compromised by water conditions.
This work is usually done by archaeologists who are qualified scientific divers.
Bathymetric and hydrographic surveys
Bathymetric surveys are traditionally done from the surface, by measuring depth (soundings) at measured positions along transect lines and later plotting the data onto a bathymetric chart, on which lines of constant depth (isobaths) may be drawn by interpolation of soundings. It is also conventional to provide a representative set of spot depths on the chart. Originally, soundings were made manually by measuring the length of a weighted line lowered to the bottom, bur after the development of accurate and reliable echo-sounding equipment it became the standard method. Data recording was automated when the equipment became available, and later precise position data was integrated into the data sets. Multibeam sonar with GPS position data corrected for vessel motion and combined in real time is the state of the art in the early 21st century.
Bathymetric surveys of some bodies of water have required different procedures, particularly for sinkholes, caverns and caves where a significant portion of the bottom walls, and in some cases ceilings, are not visible to the sounding equipment from the surface, and it has been necessary to use remotely operated underwater vehicles or divers to gather the data. One of the complications of this class of underwater survey is the relative difficulty of establishing a baseline, or an accurate position for the ROUV, as GPS signals do not propagate through water. In some cases a physical line has been used, but sometimes a baseline can be established using sonar transducers set up at accurately surveyed positions, and relative offsets measured.
Ecological surveys
Various techniques have been used for underwater ecological surveys. Divers are frequently used to collect data, either by direct observation and recording, or by photographic recording at recorded locations, which may be specified to a given precision depending on the requirements of the project and available location technology.
One method is for divers to use geolocated photographs taken by divers following a route recorded by a towed surface GPS receiver on a float kept above the camera by line tension. Date and time data are recorded concurrently by the camera and GPS unit, allowing position data for each photo to be extracted by post-processing or inspection. GPS precision may be augmented by Wide Area Augmentation System (WAAS). Depth data may be captured on camera from dive computers or depth gauges carried by the divers or mounted in view of the camera. The photos may be viewed on a map or via a geographic information system (GIS) for analysis. This method can also be used for spatial surveys of small areas, particularly in places where a survey vessel cannot go. To map an area the diver tows the float along bottom contours and the GPS track is used to create a map using drafting or GIS software. Spot depths may also be taken, using a digital camera to record time and depth from a depth gauge or dive computer to synchronize with the track data. This procedure can be combined with photographic recording of the benthic communities at intervals along the contour or perimeter.
Surveys by professional divers tend to be relatively expensive, and some ecological monitoring programs and data gathering programs have enlisted the aid of volunteer recreational divers to conduct data collection appropriate to their certification and in some cases, further training, such as the Australian-based Reef Life Survey. Others, such as iNaturalist, have used the crowdsourcing system of uploaded digital photographic records of observations, with location data to whatever standard is available, which can vary considerably, thereby taking advantage of the thousands of amateur photographers who record their underwater surroundings anyway. In this way millions of observations from dive sites all over the world have been accumulated.
Types of ecological survey:
Sometimes more than one type of observations are combined in a survey. For example, the Reef Life Survey procedure includes three components along the same transect: Visual count of fish, visual count of benthic fauna, and photographs of the bottom at regular intervals.
Geological surveys
A geological survey is the systematic investigation of the geology beneath a given piece of ground for the purpose of creating a geological map or model. Underwater geological surveying employs techniques from the underwater equivalent of a traditional walk-over survey, studying outcrops and landforms, to intrusive methods, such as boreholes, to the use of geophysical techniques and remote sensing methods. An underwater geological survey map typically superimposes the surveyed extent and boundaries of geological units on a bathymetric map, together with information at points (such as measurements of orientation of bedding planes) and lines (such as the intersection of faults with the seabed surface). The map may include cross sections to illustrate the three-dimensional interpretation. Much of this work is done from surface vessels by remote sensing, bur in some cases such as in flooded caves, measurement and sampling requires remotely operated underwater vehicles or direct intervention by divers.
Reflection seismology techniques are used for shipborne subsurface remote sensing. Seismic sources include air guns, sparkers and boomers.
Airborne geophysical methods include magnetic, electromagnetic, and gravity measurement.
Site surveys
Site surveys are inspections of an area where work is proposed, to gather information for a design. It can determine a precise location, access, best orientation for the site and the location of obstacles. The type of site survey and the best practices required depend on the nature of the project. In hydrocarbon exploration, for example, site surveys are run over the proposed locations of offshore exploration or appraisal wells. They consist typically of a tight grid of high resolution (high frequency) reflection seismology profiles to look for possible gas hazards in the shallow section beneath the seabed and detailed bathymetric data to look for possible obstacles on the seafloor (e.g. shipwrecks, existing pipelines) using multibeam echosounders.
A type of site survey is performed during marine salvage operations, to assess the structural condition of a stranded vessel and to identify aspects of the vessel, site and environment that may affect the operation. Such a survey may include investigation of hull structural and watertight integrity, extent of flooding, bathymetry and geology of the immediate vicinity, currents and tidal effects, hazards, and possible environmental impact of the salvage work.
Structural surveys
Structural integrity inspections of inland, coastal and offshore underwater structures, including bridges, dams, causeways, harbours, breakwaters, jetties, embankments, levees, petroleum and gas production platforms and infrastructure, pipelines, wellheads and moorings.
Vessel safety surveys
Vessel safety surveys are inspections of the structure and equipment of a vessel to assess the condition of the surveyed items and check that they comply with legal or classification society requirements for insurance and registration. They may occur at any time when there is reason to suspect that the condition has changed significantly since the previous survey, or as a condition of purchase, and the first survey is generally during construction (built under survey) or before first registration. The criteria for acceptance are defined by the licensing or registration authority for a variety of equipment vital to the safe operation of the vessel, such as hull structure, static stability, propulsion machinery, auxiliary machinery, safety equipment, lifting equipment, rigging, ground tackle, etc.
Some surveys must be done in dry dock, but this is expensive, and in some cases for intermediate surveys the underwater part of the external survey may be done afloat using divers or ROUVs to do the inspection, usually providing live video to the surveyor, or possibly video recording for later analysis. Live video has the advantage that the surveyor can instruct the diver to investigate further or provide views from other angles. Live video would normally also be recorded for the records.
Tools
Remote measurement through water
Single beam echosounders are used to measure distance of a reflecting surface, like the seabed, by comparing the time between emission of a sound signal and first receiving the reflected signal back at the transceiver, using the speed of sound in water. They are usually used to make a series of spot depth measurements along the path of the transducer, which can be used to map the bottom profile.
Multibeam echosounders use beamforming to extract directional information from the returning sound waves, producing a swath of depth readings across the path of the transducer from a single ping. The rate of data acquisition is far greater than for single beam systems, but they are susceptible to shadowing effects from high-profile surfaces offset to the side of the transducer path. This can be compensated by overlapping swaths. The data is processed to give a three dimensional image of the bottom.
Acoustic Doppler current profilers (ADCP) are hydro-acoustic current meters, used to measure water current velocities over a depth range using the Doppler effect of sound waves scattered back from particles within the water column. The traveling time of the sound waves gives the distance, and the frequency shift of the echo is proportional to the water velocity along the acoustic path.
Lidar uses a laser light source and optical receiver to measure range and direction of reflected signals, but is limited by the water transparency.
Side-scan sonar is used to efficiently create images of large areas of the sea floor, as seen from the point of view of the transducer.
Seismic sources such as sparkers and boomers are used in seismic reflection profiling, using sound pulse frequencies that effectively penetrate the solid seabed and are partially reflected by changes in acoustic impedance, often signifying a change in rock type. Boomers work in the 500 to 4000 Hz range. and sparkers in the 200 to 800 Hz range. Lower frequency will usually penetrate to greater depth, but with lower resolution.
Platforms
Dedicated survey vessels and vessels of opportunity. Diving support vessels for surface-supplied diving operations, and dive boats for scuba surveys. DSVs are often fitted for ROV support and other underwater surveys.
Autonomous survey vessels are more economical to operate than crewed vessels, and can be sent into waters that are too shallow or confined or otherwise hazardous for larger crewed vessels.
Autonomous underwater vehicles are more economical than crewed vehicles. Researchers have focused on the development of AUVs for long-term data collection in oceanography and coastal management. The oil and gas industry uses AUVs to make detailed maps of the seafloor before they start building subsea infrastructure. The AUV allows survey companies to conduct precise surveys of areas where traditional bathymetric surveys would be less effective or too costly. Also, post-lay pipe surveys which include pipeline inspection are possible. The use of AUVs for pipeline inspection and inspection of underwater man-made structures is becoming more common. Scientists use AUVs to study lakes, the ocean, and the ocean floor. A variety of sensors can also be carried to measure the concentration of various elements or compounds in the water, the absorption or reflection of light, and the presence of microscopic life. Examples include conductivity-temperature-depth sensors (CTDs), chlorophyll fluorometers, and pH sensors.
Remotely operated underwater vehicles. Survey or inspection ROVs are generally smaller than workclass ROVs and are often sub-classified as either Class I: Observation Only or Class II Observation with payload. They are used to assist with hydrographic survey, and also for inspection work. Survey ROVs, although smaller than workclass, often have comparable performance with regard to the ability to hold position in currents, and often carry similar tools and equipment - lighting, cameras, sonar, USBL (Ultra-short baseline) beacon, and strobe flasher depending on the payload capability of the vehicle and the needs of the user.
Underwater position measurement systems
Underwater acoustic positioning systems are systems for the tracking, navigation and location of underwater vehicles or divers by means of acoustic distance and/or direction measurements, and subsequent position triangulation. They are commonly used in a wide variety of underwater work, including oil and gas exploration, ocean sciences, salvage operations, marine archaeology, law enforcement and military activities.
Long baseline acoustic positioning systems (LBL systems) use networks of sea-floor mounted baseline transponders as reference points for navigation. These are generally deployed around the perimeter of a work site. The LBL technique results in very high positioning accuracy and position stability that is independent of water depth. It is generally better than 1-meter and can reach a few centimeters accuracy. LBL systems are generally used for precision underwater survey work where the accuracy or position stability of ship-based short or ultra-short baseline positioning systems does not suffice.
Short baseline acoustic positioning system (SBL acoustic positioning systems) SBL systems do not require any seafloor mounted transponders or equipment and are thus suitable for tracking underwater targets from boats or ships that are either anchored or under way. However, unlike USBL systems, which offer a fixed accuracy, SBL positioning accuracy improves with transducer spacing. Thus, where space permits, such as when operating from larger vessels or a dock, the SBL system can achieve a precision and position robustness that is similar to that of sea floor mounted LBL systems, making the system suitable for high-accuracy survey work. When operating from a smaller vessel where transducer spacing is limited (i.e. when the baseline is short), the SBL system will exhibit reduced precision.
Ultra-short baseline acoustic positioning system (USBL), also known as super short base line (SSBL), consists of a transceiver, which is mounted under a ship, and a transponder or responder on the seafloor, on a towfish, or on an ROV. A computer, is used to calculate a position from the ranges and bearings measured by the transceiver. USBLs are also used in "inverted" (iUSBL) configurations, with the transceiver mounted on an autonomous underwater vehicle, and the transponder on the installation that launches it. In this case, the signal processing happens inside the vehicle to allow it to locate the transponder for applications such as automatic docking and target tracking.
Manual measurement underwater
Measurements can be made using a variety of instruments. Vertical position relative to the surface, also known as depth measurement, may use:
Depth gauges (using pressure as a proxy)
Dive computers (using pressure as a proxy)
Measuring tapes (direct linear measurement)
Pneumofathometers (using pressure as a proxy)
Length measurement in other directions, using:
Measuring tape,
Surveyor's chain,
Calibrated distance line, particularly in cave surveys,
Towed GPS receivers on floats (by spherical trigonometry)
Inertial navigation system, integrated from accelerometer output in three dimensions
Hand-held range-finding sonar
Vernier and plain calipers, for small dimensions.
Length measurements may also be derived by triangulation from a baseline, angular measurement, and trigonometry
Angular measurements may be made using:
Magnetic compass
Protractor
Clinometer
Goniometer
Or may be derived from GPS positions, from linear triangulation and trigonometry, and from inertial navigation position data.
Non-destructive testing measurements may include:
Ultrasonic thickness measurement
Ultrasonic crack detection
Measurements of visibility, using Secchi discs and similar methods, and spot measurements of other physical and chemical characteristics by local measurementor recording by a diver, or sampling of the water and bottom composition.
Sampling and specimen collection
Samples of seafloor sediments and rock can be collected using grabs, coring devices, ROUVs and divers. Coring devices include core drills and impact penetrators. Divers and ROUV operators are more discriminating in their selection of samples than grabs and remotely operated coring devices. Biological samples can be collected by dredges, grabs, traps, or nets, but more directed sampling generally requires visual input and human intervention, and is commonly done by divers, ROUVs and crewed submersibles equipped for collection.
Recording and counting
Underwater photography. Digital underwater cameras can conveniently be used to record an image, and the time at which the photo was taken. In some cases direction, inclination and depth are also available from the camera, or can be recorded by photographing the display of appropriate instruments.
Jump cameras are cameras mounted on a frame that triggers an exposure when the frame hits the bottom. To operate, the frame is lowered until the rope slacks off, then lifted and the boat moved to the next position.
Underwater videography, the branch of electronic underwater photography concerned with capturing underwater moving images, and live video feeds, which allow a remote operator to see the underwater environment from elsewhere.
Baited remote underwater video (BRUV) is a system used in marine biology research. By attracting fish into the field of view of a remotely controlled camera, the technique records fish diversity, abundance and behaviour of species. Sites are sampled by video recording the region surrounding a baited canister which is lowered to the bottom. The video can be transmitted directly to the surface by cable, or recorded for later analysis. Baited cameras are highly effective at attracting scavengers and subsequent predators, and are a non-invasive method of generating relative abundance indices for a number of marine species.
Checklists are useful when a reasonably small range of objects or types of object are to be recorded as being present, as they reduce the amount of writing that must be done underwater. (legibility tends to suffer in cold water or in moving water)
Clipboard or and pencil, are used when sketches and measurements are to be recorded, and are versatile though not very efficient for data recording. Waterproof paper is available for use on clipboards, and can be printed with checklists.
Quadrat frames are used to establish a discrete area for examination, and can be visually examined, photographed, or both.
Presentation of results
Results of underwater surveys can be presented in several ways, depending on the target demographic and intended use of the data.
A common presentation format is a map indicating spatial distribution or general topography, often involving a depth dimension. Drawings, photographic images, graphs, tables, and text descriptions may also be used, often in conjunction with one or more maps. Maps may also be used to indicate variations over time in comparison with a baseline.
See also
References
Sonar
Geodesy
Underwater work
Surveying | Underwater survey | [
"Mathematics",
"Engineering"
] | 4,226 | [
"Applied mathematics",
"Civil engineering",
"Surveying",
"Geodesy"
] |
70,875,686 | https://en.wikipedia.org/wiki/15%20Trianguli | 15 Trianguli is a suspected variable star located in the northern constellation Triangulum, with an apparent magnitude of 5.4 making it faintly visible to the naked eye under ideal conditions, although it is suspected of being an irregular variable with a range of 0.14 magnitudes. The star is situated about 480 light years away but is approaching with a heliocentric radial velocity of .
15 Trianguli has a stellar classification of M3 III. It has 1.7 times the mass of the Sun and 118 times the radius of the Sun. It has an effective temperature of and shines at 1,668 times the luminosity of the Sun from its photosphere, giving it an orange glow. It is an asymptotic giant branch star, which means it is fusing hydrogen and helium in separate shells around an inert carbon core.
References
M-type giants
Triangulum
Trianguli, 15
016058
012086
0750
Durchmusterung objects | 15 Trianguli | [
"Astronomy"
] | 203 | [
"Triangulum",
"Constellations"
] |
70,875,914 | https://en.wikipedia.org/wiki/13%20Delphini | 13 Delphini is a binary star in the equatorial constellation Delphinus, with a combined apparent magnitude of 5.64. The system is located at a distance of 471 light years but is approaching the Solar System with a heliocentric radial velocity of about .
13 Delphini A has an apparent magnitude of 5.66, while its companion has an apparent magnitude of 8.51. As of 2016, the pair have a separation of located at a position angle of .
13 Delphini has a blended stellar classification of A0 V, indicating that it is an ordinary A-type main-sequence star. However, when the components are analysed individually, the primary star is given a class of B9V. It has 2.51 times the mass of the Sun and has an effective temperature of 9,840 K. However, the star is large for its class, having a radius almost 4 times that of the Sun and a luminosity 119 times greater. This is due to 13 Delphini having completed 86.1% of its main sequence lifetime and has led one source to classify it as a subgiant instead. It spins rapidly with a projected rotational velocity of and has an age of 307 million years.
References
Delphinus
A-type main-sequence stars
Delphini, 13
Delphini, 18
BD+05 4613
198069
102633
7953
Binary stars | 13 Delphini | [
"Astronomy"
] | 290 | [
"Delphinus",
"Constellations"
] |
70,876,095 | https://en.wikipedia.org/wiki/Schilling%20%28unit%29 | As well as being the name of a coin, the Schilling was an historical unit in three areas of measurement: numbers, volume and weight. It can be regarded as a European measure, because it was used in Bohemia, Bavaria, Silesia, Austria and Lusatia.
In Bohemian mines it was a measure of volume that corresponded to 5 wheelbarrows. The schilling was determined as follows:
1 schilling = 12 leather skins filled with water = 480 Prague pints
18 schillings = 1 quantity (Losung) of water
In Regensburg the measure was applied to salt. In Bavaria, for example, it was used as a number and a weight.
1 schilling salt = 40 'slices' (Salzscheiben)
8 schillings = 1 Pfund ("pound") of salt
In Austria a schilling corresponded to the number 30 and
in Silesia and Lusatia, the number 12. In the regional dialect it was called a Schilger in Silesia and a Schilger or Schilk in Lusatia.
240 pfennigs were minted from the 367 g Carolingian pound of silver. A schilling was determined to be twelve pfennigs, but was initially not an actual coin.
Footnotes
References
Literature
Joachim Heinrich Campe: Wörterbuch der deutschen Sprache. Volume 4, Brunswick: Schulbuchhandlung, 1810, p. 141
Obsolete units of measurement
Units of amount
Units of mass
Units of volume
Units of measurement of the Holy Roman Empire | Schilling (unit) | [
"Physics",
"Mathematics"
] | 322 | [
"Obsolete units of measurement",
"Matter",
"Units of volume",
"Units of amount",
"Quantity",
"Units of mass",
"Mass",
"Units of measurement"
] |
70,877,973 | https://en.wikipedia.org/wiki/Glossip%20v.%20Chandler | Glossip v. Chandler is a United States District Court for the Western District of Oklahoma case in which the plaintiffs challenged the State of Oklahoma's execution protocol. The initial lawsuit, Glossip v. Gross, rose to the United States Supreme Court in 2015 at the preliminary injunction stage and involved an earlier version of Oklahoma's lethal injection protocol. The case was reopened in the District Court in 2020 following an end to Oklahoma's moratorium on executions.
Background
Execution of Clayton Lockett
In 2014, Oklahoma's lethal injection protocol came under scrutiny when Clayton Lockett died of a heart attack resulting from complications during his execution. Lockett was convicted of the 1999 kidnapping, rape, and murder of a 19-year-old woman. In 2015, Lockett and other death row inmates had unsuccessfully challenged an Oklahoma law allowing the names of companies supplying drugs used in executions to be kept secret in Glossip v. Gross. Lockett was scheduled to be executed on April 29, 2014, and after doctors had declared him unconscious, Lockett attempted to raise his head and speak and complained of a burning sensation. Lockett started convulsing after receiving a round of lethal drug injections. Governor Fallin asked the Department of Corrections to conduct a full review of the state's execution procedures. Autopsy reports indicated that Oklahoma State Penitentiary officials had used potassium acetate instead of potassium chloride and that Lockett had died of a heart attack during the execution.
Initial lawsuit Glossip v. Gross
On June 25, 2014, twenty-one Oklahoma death row inmates filed a lawsuit, Charles F. Warner, et al., v. Kevin J. Gross, et al., in the United States District Court for the Western District of Oklahoma. The lawsuit claimed that Oklahoma's execution protocol was unconstitutional, stating that there is autopsy evidence suggesting that the drugs used in lethal injection make people feel as though they are drowning through a "flash pulmonary edema" and like they are being "burned alive" violating the Eighth and Fourteenth amendments of the U.S. Constitution. Richard Glossip replaced Charles Frederick Warner as the named plaintiff after Warner was executed in January 2015 before the case was decided.
The lawsuit advanced to the United States Supreme Court, and on June 29, 2015, the justices ruled 5–4 in Glossip v. Gross that the prisoners had not shown that they would be subject to an unconstitutional level of pain. The court also ruled that death row inmates challenging their execution method must present a known and available alternative. The executions of Richard Glossip, John Grant, and Benjamin Cole Sr. were stayed by the court. The lawsuit was then returned to the United States District Court for the Western District of Oklahoma. Following the Supreme Court's ruling, in October 2015 state officials imposed an execution moratorium, and the case was administratively closed by agreement for an indefinite period of time to permit the state to investigate and amend its execution procedures.
Execution of Charles Frederick Warner
On January 15, 2015, Charles Frederick Warner was executed. On September 30, 2015, in investigations surrounding the planned execution of Richard Glossip, it became apparent that potassium acetate may have been used to execute Warner. After his execution, the drug vials and syringes used in Warner's execution were submitted to the Office of Chief Medical Examiner. On October 8, 2015, it was reported that, contrary to protocol, the Oklahoma Department of Corrections officials had used potassium acetate to execute Warner on January 15, 2015. An attorney representing Glossip and other Oklahoma death row inmates said logs from Warner's execution initialed by a prison staff member indicated the use of potassium chloride; however, an autopsy report showed twelve vials of potassium acetate were used.
Planned execution of Richard Glossip
Oklahoma planned to execute Richard Glossip on September 30, 2015. Officials discovered that they had been delivered the drug potassium acetate instead of potassium chloride, which had been used in the botched execution of Lockett. After learning of the discrepancy, Governor of Oklahoma Mary Fallin called off Glossip's execution with a last-minute, indefinite stay, claiming it was a precaution since the doctor and pharmacist working with the Department of Corrections agreed that potassium chloride and potassium acetate were medically interchangeable. Scott Pruitt, Oklahoma Attorney General at the time, ordered a multicounty grand jury investigation of the execution drug error.
Moratorium
The several botched executions resulted in a moratorium on executions in Oklahoma from October 2015 until 2021. On February 13, 2020, Oklahoma announced plans to resume executions in a press conference attended by Governor Kevin Stitt, Oklahoma Attorney General Michael J. Hunter and Department of Corrections Director Scott Crow. Stitt stated that "It is important that the state is implementing our death penalty law with a procedure that is humane and swift for those convicted of the most heinous of crimes, and claimed that Oklahoma had found a "reliable supply of drugs" to resume lethal injections.
Reopening of lawsuit
Following the end of the moratorium, on February 27, 2020, more than two dozen inmates filed a Motion to Reopen Case by All Plaintiffs, claiming the new lethal injection protocol was incomplete. Although the case had been before the United States Supreme Court at the preliminary injunction stage, that had involved an earlier version of Oklahoma's lethal injection protocol. On March 19, 2020, the case was officially reopened. The plaintiffs claim the sedative midazolam, one of three drugs administered during Oklahoma's execution process, causes fluid to quickly build up in the lungs, creating a feeling of suffocation. They also claim that a second drug, potassium chloride, causes extreme pain "similar to being burned alive" if the person being executed maintains consciousness. The State of Oklahoma claims that the previously botched executions were caused by inadequate training and relaxed protocols. The State claims the protocols and training have since been updated and corrected.
In May 2020, the Attorney General of Oklahoma told the court it would not set execution dates for any of the prisoners named in the lawsuit. On July 6, 2020, a Third Amended Complaint was filed in the case and the case name was changed to Richard Glossip, et al., v. Randy Chandler et al.. This amended complaint challenges the state's new execution protocol.
In August 2021, United States District Court for the Western District of Oklahoma Judge Stephen Friot dismissed parts of the Third Amended Complaint, ruling that because six inmates had not specified an alternative execution method to lethal injection, they could no longer be included in the lawsuit. Several of the inmates refused to choose an alternative method of execution based on religious grounds. Following their removal from the lawsuit, the Oklahoma Court of Criminal Appeals set execution dates for five of the former plaintiffs, including John Grant, Julius Jones, Donald Grant, Gilbert Postelle, and James Coddington. The remaining twenty-six plaintiffs were allowed to proceed on challenges to Oklahoma's execution protocol under the United States Constitution, the Oklahoma Constitution and other laws.
On October 15, 2021, United States Court of Appeals for the Tenth Circuit ruled that the lower court made a mistake by dismissing the six prisoners from the lawsuit. Despite the former attorney general's earlier commitment to stay execution dates for plaintiffs in the lawsuit, his successor, John M. O'Connor, moved forward with scheduling dates, and John Grant was executed on October 28, 2021. An autopsy showed that John Grant suffered a flash pulmonary edema, which is a rapid build-up of fluid creating the feeling of suffocation or drowning. In addition to the edema, John Grant experienced intramuscular hemorrhaging and aspirated on his vomit as a direct result of the lethal injection.
Following the botched October 2021 execution of John Grant, four Oklahoma death row inmates who had scheduled execution dates, Gilbert Postelle, Julius Jones, Wade Lay, and Donald Grant, sued for an injunction. They argued that Oklahoma officials had not resolved concerns about the state's execution method and asked that their executions be stayed until a hearing could be held on February 28, 2022. In November 2021, the United States Court of Appeals for the Tenth Circuit rejected the inmates' request to intervene. On January 27, 2022, the day Donald Grant was scheduled to be executed, Donald Grant and Gilbert Postelle requested an emergency stay of execution from the United States Supreme Court which was denied. Donald Grant was executed by lethal injection and declared dead at 10:16 a.m CST. On February 17, 2022, Postelle was executed by lethal injection and was pronounced dead at 10:14 a.m. CST.
See also
Glossip v. Gross (2015)
Execution of Clayton Lockett
Execution of John Grant
Execution of Joseph Wood
List of botched executions
References
Capital punishment in Oklahoma
Lethal injection
2015 in United States case law
2022 in United States case law
Cruel and Unusual Punishment Clause and death penalty case law | Glossip v. Chandler | [
"Environmental_science"
] | 1,807 | [
"Toxicology",
"Lethal injection"
] |
70,878,793 | https://en.wikipedia.org/wiki/NGC%204868 | NGC 4868 is an unbarred spiral galaxy located about 240 million light-years away in the constellation Canes Venatici. It was discovered by William Herschel on March 17, 1787. A 2002 study suggests that a quasar may exist within NGC 4868.
See also
List of galaxies
New General Catalogue
References
4868
Canes Venatici
Unbarred spiral galaxies | NGC 4868 | [
"Astronomy"
] | 82 | [
"Canes Venatici",
"Constellations"
] |
70,879,190 | https://en.wikipedia.org/wiki/Innodisk | Innodisk Corporation () is a Taiwanese provider of industrial embedded flash and storage products and technologies, with a focus on enterprise, industrial and aerospace industries. Founded in 2005 and headquartered in Xizhi District, New Taipei City, its products are mainly embedded storage devices, dynamic random access memory modules, embedded peripheral modules, software and related technical services.
History
Innodisk was formally established in Taiwan in March 2005. Subsidiaries were established in the following years, with the U.S. subsidiary in October 2008, the subsidiary in Japan in February 2010 and a subsidiary in China in January 2011.
An office in the Netherlands was established in April 2012, which was restructured into a Dutch subsidiary in January 2015.
The company went public in August of the same year and was listed in October 2012. In November 2013 the stocks were listed on the OTC.
In January 2013, the company launched a new corporate identity image. In December 2015, the company established the Innodisk International Education Foundation. In May 2018, a R&D and Manufacturing Center was completed in Yilan, Taiwan.
Awards and recognitions
November 2018: Selected as Top 35 Taiwanese International Brands
October 2019: Selected as Top 35 International Brands in Taiwan
March 2019: The Dutch branch opens a new office in Eindhoven
November 2020: Selected as Top 35 International Brands in Taiwan
See also
List of companies of Taiwan
References
Companies listed on the Taipei Exchange
Computer companies of Taiwan
Computer hardware companies
Computer peripheral companies
Electronics companies established in 2005
Electronics companies of Taiwan
Manufacturing companies based in New Taipei
Multinational companies headquartered in Taiwan
Taiwanese brands
Taiwanese companies established in 2005 | Innodisk | [
"Technology"
] | 319 | [
"Computer hardware companies",
"Computers"
] |
70,879,247 | https://en.wikipedia.org/wiki/Naimi%E2%80%93Trehel%20algorithm | The Naimi–Trehel algorithm is an algorithm for achieving mutual exclusion in a distributed system.
Unlike Lamport's distributed mutual exclusion algorithm and its related version, this algorithm does not use logical clocks.
This method requires only O(log(number of processes in the network)) messages on average.
When a process invokes a critical section, it sends a request to a queue at a particular processor which is specified by a path built by the algorithm as it runs.
References
article at citeseerx.ist.psu.edu by Mohamed Naimi, Michel Trehel, André Arnold
Concurrency control algorithms
Distributed computing | Naimi–Trehel algorithm | [
"Technology"
] | 128 | [
"Computing stubs",
"Computer science",
"Computer science stubs"
] |
70,879,464 | https://en.wikipedia.org/wiki/Netherlands%20Research%20School%20for%20Astronomy | The Netherlands Research School for Astronomy (Dutch: Nederlandse Onderzoekschool voor Astronomie, also known as NOVA) is a graduate school specializing in astronomy, based in the Netherlands. This graduate school was founded in 1992.
Formation and partners
NOVA was formed by a federated partnership of the following institutions:
Anton Pannekoek Institute for Astronomy (University of Amsterdam),
Kapteyn Institute (University of Groningen),
the Leiden Observatory (Leiden University), and
Radboud University (in Nijmegen).
The astronomical institute of Utrecht University was also part of NOVA until it closed in 2012.
Three of the top research institutions that NOVA collaborates with internationally are Max Planck Society, Harvard University, and Center for Astrophysics Harvard & Smithsonian (CfA).
Goals, activities, and research areas
This graduate school has two main goals. The first goal is to conduct advanced astronomical research, and the second is to educate young astronomers at the highest international level.
Education
NOVA is involved in, among other things, distributing funds for hiring PhD students, as well as communicating astronomical research results to the press, the general public and primary and secondary education. NOVA also organizes the annual autumn school in which every astronomical PhD student participates at least once.
NOVA possesses three inflatable mobile planetariums that visit approximately 200 primary and secondary schools annually, reaching about 30,000 students per year. After an initial stop in activities during 2020 due to the COVID-19 pandemic in the Netherlands, NOVA resumed classroom visits with a high quality flat screen, pending resumption of the inflatable technique.
Support for research
Coordinating national scientific policy in the field of astronomy is among NOVA's tasks. NOVA also helps to fund telescope projects, for example the Africa Millimetre Telescope.
Astronomical research is divided by NOVA into three parts:
Origin and evolution of galaxies: from the big bang to the present
Formation and evolution of stars and planets
Astrophysics of Neutron Stars and Black Holes
Leaders, facilities, and discoveries
Since 2007, Ewine van Dishoeck has been scientific director of NOVA, and from 2017 Huub Röttgering has been chairman of the board.
NOVA astronomers rely heavily on the European Southern Observatory (ESO), most notably the Very Large Telescope (VLT) and the Atacama Large Millimeter Array (ALMA). A large fraction of the instrument projects that NOVA participates in are targeted at these facilities, as well as the future Extremely Large Telescope.
Among recent discoveries made by NOVA astronomers, one pertains to NGC 2005 which is a spherical globular cluster in the Large Magellanic Cloud (LMC). NOVA announced in 2021 proof that NGC 2005 is a relic from the merger of a smaller galaxy into the LMC, i.e. one galaxy got eaten by another.
References
External links
•NOVA home page
Astronomy institutes and departments
Astronomy in the Netherlands | Netherlands Research School for Astronomy | [
"Astronomy"
] | 589 | [
"Astronomy organizations",
"Astronomy institutes and departments"
] |
70,880,915 | https://en.wikipedia.org/wiki/375-line%20television%20system | 375-line corresponds to two different electronic television systems, both using 375 scan lines. One system (monochrome, 50 fields per second, interlaced) was used in Germany after 1936 along with the 180-line system, being replaced in a few years by the superior 441-line system. It was also tested in Italy around the same time.
In the United States a completely different system (field sequential color, 120 fields per second, interlaced) was used for early color television broadcasts
Germany
375-line (50 fps, interlaced) television was demonstrated in 1936 on the Berlin Funkausstellung. The system used electronic cameras for live exterior broadcasts.
The system was also used on experimental transmissions of the 1936 Summer Olympics (along with the 180-line system), using the Telefunken Iconoscope camera. A transmitter was setup in Berlin-Witzleben, broadcasting at 42.9 MHz. The Reichspost distributed the signal to major cities across Germany using cables.
After the Games transmissions continued to viewing rooms installed on post offices. Philips presented a radio/TV combo receiver for the system at the 1937 Berlin Funkausstellung, and Loewe also had a receiver available.
In the same year Telefunken demonstrated the 375-line system at the Paris Exposition Internationale des Arts et Techniques dans la Vie Moderne, displaying images taken from the exhibition's pavilion terrace.
Italy
In Italy 375-line television transmissions were undertaken by Arturo Castellani in 1937, with daily broadcasts from Rome, between 6pm and 9:30pm on 6.9 meters (43.45 MHz) with a power of 2 kW.
United States
In the spring of 1940, CBS staff engineer Peter Goldmark devised a system for color television, hoping to gain advantage regarding NBC and its black-and-white RCA system. The new system proposed by CBS was based on field sequential color and incompatible with existing sets but "gave brilliant and stable colors", while NBC developed a black and white compatible color TV system that was "crude and unstable but compatible".
After some tests with different line counts, on September 2, 1941, CBS announces a 375-line, 60 color frames per second system, requiring a horizontal scanning rate of 22,500 lines per second, and a vertical scanning rate of 120 fields per second (interlaced, giving a combined color picture frequency of 20 frames per second). The system was tested from CBS station WCBW New York, on June 1, 1941.
In 1945 CBS demonstrates color broadcast using test equipment and a 10 MHz bandwidth UHF channel. Later developments use higher line counts (525-line with 144 fields/second using 10 MHz video bandwidth and 441-line with 144 fields/second using 4 MHz video bandwidth are proposed in 1946), but system operation (field sequential, using a high bandwidth UHF channel) remained similar the 375-line tests.
Eventually it was shown to the general public on January 12, 1950 as the 405-line Field-Sequential Color System (FSC). The vertical resolution was 77% of monochrome, and the horizontal resolution was 54% of monochrome. The Federal Communications Commission adopted it on October 11, 1950, as the standard for color television in the United States, but it was later withdrawn.
The concept was revived by NASA in the 1960 for the Apollo color TV cameras.
References
Television technology | 375-line television system | [
"Technology"
] | 688 | [
"Information and communications technology",
"Television technology"
] |
58,479,141 | https://en.wikipedia.org/wiki/The%20Psychological%20Record | The Psychological Record is a quarterly peer-reviewed scientific journal covering behavior analysis. It was established in 1937 by Jacob Robert Kantor, with B.F. Skinner serving as founding editor of the journal's experimental department. It is published by the Association for Behavior Analysis International in partnership with Springer Science+Business Media; before that, it was published by Southern Illinois University, Carbondale. The editor-in-chief is Mitchell Fryling (California State University, Los Angeles). According to the Journal Citation Reports, the journal has a 2017 impact factor of 1.026.
See also
Florence DiGennaro Reed
References
External links
Behaviorism journals
Springer Science+Business Media academic journals
Quarterly journals
Academic journals established in 1937
Academic journals published by international learned and professional societies
English-language journals | The Psychological Record | [
"Biology"
] | 158 | [
"Behavior",
"Behaviorism",
"Behaviorism journals"
] |
58,479,429 | https://en.wikipedia.org/wiki/Ilona%20Pal%C3%A1sti | Ilona Palásti (1924–1991) was a Hungarian mathematician who worked at the Alfréd Rényi Institute of Mathematics. She is known for her research in discrete geometry, geometric probability, and the theory of random graphs.
With Alfréd Rényi and others, she was considered to be one of the members of the Hungarian School of Probability.
Contributions
In connection to the Erdős distinct distances problem, Palásti studied the existence of point sets for which the th least frequent distance occurs times. That is, in such points there is one distance that occurs only once, another distance that occurs exactly two times, a third distance that occurs exactly three times, etc. For instance, three points with this structure must form an isosceles triangle. Any evenly-spaced points on a line or circular arc also have the same property, but Paul Erdős asked whether this is possible for points in general position (no three on a line, and no four on a circle). Palásti found an eight-point set with this property, and showed that for any number of points between three and eight (inclusive) there is a subset of the hexagonal lattice with this property. Palásti's eight-point example remains the largest known.
Another of Palásti's results in discrete geometry concerns the number of triangular faces in an arrangement of lines. When no three lines may cross at a single point, she and Zoltán Füredi found sets of lines, subsets of the diagonals of a regular -gon, having triangles. This remains the best lower bound known for this problem, and differs from the upper bound by only triangles.
In geometric probability, Palásti is known for her conjecture on random sequential adsorption, also known in the one-dimensional case as "the parking problem". In this problem, one places non-overlapping balls within a given region, one at a time with random locations, until no more can be placed. Palásti conjectured that the average packing density in -dimensional space could be computed as the th power of the one-dimensional density. Although her conjecture led to subsequent research in the same area, it has been shown to be inconsistent with the actual average packing density in dimensions two through four.
Palásti's results in the theory of random graphs include bounds on the probability that a random graph has a Hamiltonian circuit, and on the probability that a random directed graph is strongly connected.
Selected publications
References
1924 births
1991 deaths
20th-century Hungarian mathematicians
Women mathematicians
Graph theorists
Probability theorists | Ilona Palásti | [
"Mathematics"
] | 517 | [
"Mathematical relations",
"Graph theory",
"Graph theorists"
] |
58,479,919 | https://en.wikipedia.org/wiki/Chemical%20Institute%20of%20Canada%20Medal | The Chemical Institute of Canada Medal or CIC Medal is the highest award that the Chemical Institute of Canada confers. Awarded annually since 1951, it is given to "a person who has made an outstanding contribution to the science of chemistry or chemical engineering in Canada".
The medal is presented at the annual Canadian Chemistry Conference and Exhibition or Canadian Chemical Engineering Conference, at which the recipient gives a plenary lecture.
The award commemorates the isolation of nickel by Frederik Cronstedt in 1751. The medals were originally sponsored by the International Nickel Company and consisted of 8 ounces (227g) of pure palladium. The sponsorship ended in 2006, since when the medals have been made of silver plated nickel.
Winners
Source (recent winners): CIC
See also
List of chemistry awards
References
Chemistry awards
Canadian science and technology awards | Chemical Institute of Canada Medal | [
"Technology"
] | 168 | [
"Science and technology awards",
"Chemistry awards"
] |
58,479,967 | https://en.wikipedia.org/wiki/Textfree | TextFree (formerly called Pinger and sometimes stylized as textfree) is a mobile application and web service that allows users to send and receive text messages, as well as make and receive VoIP phone calls, for free over the internet. The service costs nothing because it is supported by ads, but users have the option of paying for an ad-free version with enhanced features. TextFree was developed by American telecommunications provider Pinger, Inc. It was released in 2006.
TextFree states on its website that it has more than 130 million users (as of September 2022).
The mobile app runs on both iOS and Android devices, and there is a desktop version available for download on macOS and Windows. Users can also access TextFree's services online via a web browser. Competitors include GOGII, Optini and WhatsApp.
Usage
Users can communicate with others who do not use the app via texting and calling. Users can call within US and Canada, while texting is free in 35 countries. New accounts receive a new phone number and 60 free minutes. Users may t allows users to send and receive text messages directly from a computer. They provide a permanent number to their users, which they can use to send free texts for lifetime.
References
Android (operating system) software
IOS software
Instant messaging clients
Cross-platform software
Communication software | Textfree | [
"Technology"
] | 274 | [
"Instant messaging",
"Instant messaging clients"
] |
58,480,203 | https://en.wikipedia.org/wiki/Rio%20Grande%20water%20resource%20region | The Rio Grande water resource region is one of 21 major geographic areas, or regions, in the first level of classification used by the United States Geological Survey to divide and sub-divide the United States into successively smaller hydrologic units. These geographic areas contain either the drainage area of a major river, or the combined drainage areas of a series of rivers.
The Rio Grande region, which is listed with a 2-digit hydrologic unit code (HUC) of 13, has an approximate size of , and consists of 9 subregions, which are listed with the 4-digit HUCs 1301 through 1309.
This region includes the drainage within the United States of: (a) the Rio Grande Basin, and (b) the San Luis Valley, North Plains, Plains of San Agustin, Mimbres River, Estancia, Jornada Del Muerto, Tularosa Valley, Salt Basin, and other closed basins. Includes parts of Colorado, New Mexico, and Texas.
List of water resource subregions
See also
List of rivers in the United States
Water resource region
References
Lists of drainage basins
Drainage basins
Watersheds of the United States
Regions of the United States
Resource
Water resource regions | Rio Grande water resource region | [
"Environmental_science"
] | 244 | [
"Hydrology",
"Drainage basins"
] |
58,481,679 | https://en.wikipedia.org/wiki/Amy%20Townsend-Small | Amy Townsend-Small is the director of the Environmental Studies Program as well as an associate professor in the Department of Geology and Geography at the University of Cincinnati.
Early life and education
Townsend-Small was born in Seattle, Washington. She grew up in Holliston, Massachusetts, and graduated from Holliston High School. While attending Skidmore College in 1997, Townsend-Small spent a semester at the Marine Biological Laboratory in Woods Hole, Massachusetts as part of the Semester in Environmental Science program. During this semester she produced a research project investigating the use of nitrogen stable isotopes as tracers of wastewater inputs to groundwater, and has continued to work with isotopes and marine environments since.
In 1998, Townsend-Small graduated magna cum laude from Skidmore College, receiving a bachelor's degree in both English literature and environmental biology. She received a PhD in marine science from the University of Texas at Austin in 2006, where she had done dissertation research investigating carbon cycling and its relationship with climate in the Amazon River headwaters of Peru.
Career and research
Townsend-Small's dissertation research focused on examining the particulate organic matter (POM) carried downstream by rivers from the Andes Mountains in Peru to the Amazon River, paying special attention to the elemental and isotopic compositions of carbon and nitrogen in the POM. After receiving her PhD, Townsend-Small worked at the University of Texas at Austin as a postdoctoral researcher studying the connection between changing climate and the export of carbon, nitrogen, and dissolved nutrients in rivers of the Alaskan Arctic. In 2007, Townsend-Small began working as a Postdoctoral Scholar and Project Scientist in the Department of Earth System Science at the University of California Irvine, where she conducted research regarding urban greenhouse gas and water budgets in Los Angeles, California. Since 2010, Townsend-Small has been at the University of Cincinnati, where she is now an associate professor in the Department of Geology and Geography as well as the director of the Environmental Studies Program. Her current research at UCI investigates anthropogenic sources of methane and climate change feedbacks to the global carbon cycle.
Awards and honors
In 2010, Townsend-Small led a research project known as UC GRO (Groundwater Research of Ohio), run by the University of Cincinnati. The study involved testing samples of groundwater from eastern Ohio for dissolved methane concentrations in order to determine the relationship between contaminated groundwater and the process of hydraulic fracturing (fracking) for natural gas. In praise of the project's innovative and unique groundwater analysis techniques, the Ohio Environmental Council (OEC) awarded Townsend-Small the Science and Community Award in 2014.
References
Living people
Scientists from Seattle
People from Holliston, Massachusetts
University of Cincinnati faculty
Skidmore College alumni
University of Texas at Austin alumni
Environmental scientists
American women scientists
20th-century American scientists
21st-century American scientists
1976 births
American women academics
20th-century American women scientists
21st-century American women scientists | Amy Townsend-Small | [
"Environmental_science"
] | 580 | [
"American environmental scientists",
"Environmental scientists"
] |
58,481,934 | https://en.wikipedia.org/wiki/Aspergillus%20fructiculosus | Aspergillus fructiculosus (also known as Emericella fruticulosa, Aspergillus fruticans) is a species of fungus in the genus Aspergillus. The species was first described in 1965. It has been reported to produce sterigmatocystin.
References
fructiculosus
Fungi described in 1965
Fungus species | Aspergillus fructiculosus | [
"Biology"
] | 79 | [
"Fungi",
"Fungus species"
] |
58,481,983 | https://en.wikipedia.org/wiki/Aspergillus%20silvaticus | Aspergillus silvaticus is a species of fungus in the genus Aspergillus. It is from the Silvati section. The species was first described in 1955.
Growth and morphology
A. silvaticus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
silvaticus
Fungi described in 1955
Fungus species | Aspergillus silvaticus | [
"Biology"
] | 101 | [
"Fungi",
"Fungus species"
] |
58,482,023 | https://en.wikipedia.org/wiki/Aspergillus%20implicatus | Aspergillus implicatus is a species of fungus in the genus Aspergillus. It is from the Sparsi section. The species was first described in 1994. It has been reported to produce a versicolorin derivative.
Growth and morphology
A. implicatus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
implicatus
Fungi described in 1994
Fungus species | Aspergillus implicatus | [
"Biology"
] | 119 | [
"Fungi",
"Fungus species"
] |
58,482,063 | https://en.wikipedia.org/wiki/Aspergillus%20allahabadii | Aspergillus allahabadii is a species of fungus in the genus Aspergillus. It is from the Terrei section. The species was first described in 1962. It has been reported to produce asperphenamate, atrovenetins, butyrolactones, citrinin, and gregatins.
Growth and morphology
A. allahabadii has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
allahabadii
Fungi described in 1962
Fungus species | Aspergillus allahabadii | [
"Biology"
] | 136 | [
"Fungi",
"Fungus species"
] |
58,482,617 | https://en.wikipedia.org/wiki/Aspergillus%20ambiguus | Aspergillus ambiguus is a species of fungus in the genus Aspergillus. It is from the Terrei section. The species was first described in 1955. It has been reported to produce a butyrolactone and terrequinone A.
Growth and morphology
A. ambiguus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
ambiguus
Fungi described in 1955
Fungus species | Aspergillus ambiguus | [
"Biology"
] | 125 | [
"Fungi",
"Fungus species"
] |
58,482,629 | https://en.wikipedia.org/wiki/Aspergillus%20floccosus | Aspergillus floccosus is a species of fungus in the genus Aspergillus. It is from the Terrei section. The species was first described in 2011. It has been reported to produce aszonalenin, butyrolactones, citrinin, a decaturin, dihydrocitrinone, an isocoumarin, and serantrypinone.
Growth and morphology
A. floccosus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
floccosus
Fungi described in 2011
Fungus species | Aspergillus floccosus | [
"Biology"
] | 152 | [
"Fungi",
"Fungus species"
] |
58,482,644 | https://en.wikipedia.org/wiki/Aspergillus%20aureoterreus | Aspergillus aureoterreus is a species of fungus in the genus Aspergillus. It is from the Terrei section. The species was first described in 2011. It has been reported to produce citreoviridin.
References
aureoterreus
Fungi described in 2011
Fungus species | Aspergillus aureoterreus | [
"Biology"
] | 64 | [
"Fungi",
"Fungus species"
] |
58,482,655 | https://en.wikipedia.org/wiki/Aspergillus%20neoindicus | Aspergillus neoindicus is a species of fungus in the genus Aspergillus. It is from the Terrei section. The species was first described in 2011. It has been reported to produce citrinin, naphthalic anhydride, and atrovenetins.
Growth and morphology
A. neoindicus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
neoindicus
Fungi described in 2011
Fungus species | Aspergillus neoindicus | [
"Biology"
] | 129 | [
"Fungi",
"Fungus species"
] |
58,482,668 | https://en.wikipedia.org/wiki/Aspergillus%20pseudoterreus | Aspergillus pseudoterreus is a species of fungus in the genus Aspergillus. It is from the Terrei section. The species was first described in 2011. It has been reported to produce aspulvinones, asterriquinones, butyrolactones, citreoisocoumarin, citreoviridin, citrinin, 3-methylorsellinic acid, terrein, and terrequinone A.
Growth and morphology
A. pseudoterreus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
pseudoterreus
Fungi described in 2011
Fungus species | Aspergillus pseudoterreus | [
"Biology"
] | 162 | [
"Fungi",
"Fungus species"
] |
58,482,726 | https://en.wikipedia.org/wiki/Aspergillus%20amoenus | Aspergillus amoenus is a species of fungus in the genus Aspergillus. It is from the Versicolores section. The species was first described in 1930.
References
amoenus
Fungi described in 1930
Fungus species | Aspergillus amoenus | [
"Biology"
] | 51 | [
"Fungi",
"Fungus species"
] |
58,484,600 | https://en.wikipedia.org/wiki/Metarhizium%20granulomatis | Metarhizium granulomatis is a fungus in the family Clavicipitaceae associated with systemic mycosis in veiled chameleons. The genus Metarhizium is known to infect arthropods, and collectively are referred to green-spored asexual pathogenic fungi. This species grows near the roots of plants and has been reported as an agent of disease in captive veiled chameleons. The etymology of the species epithet, "granulomatis" refers to the ability of the fungus to cause granulomatous disease in susceptible reptiles.
History and taxonomy
Originally named Chameleomyces granulomatis, M. granulomatis resembles Paecilomyces viridis. Because of the polyphyletic nature of the genus Paecilomyces Sigler and co-workers decided this species was better accommodated in a new genus in the family Clavicipitaceae. The first documented case of M. granulomatis was seen in the Copenhagen Zoo, showing morphology similar to Metarhizium viride (previously called P. viridis). This fungus causes fatal disseminated mycosis in veiled chameleons (Chamaeleo calyptratus). Small subunit 18S rDNA (SSU), nuclear ribosomal internal transcribed spacer (ITS) ITS1-5.8S-ITS2, and domains D2 and D2 of the large subunit 28S rDNA (LSU) were used to demarcate the fungal species M. granulomatis and differentiate it from closely related species, particularly M. viride.
Growth and morphology
Colonies of M. granulomatis differ in morphology depending on the growth medium used. Colonies on Potato dextrose agar (PDA) after 3 days incubation at are white in colour and reach 3 mm in diameter. Cultures developed on Sabouraud dextrose agar (SDA) are similar in appearance although they grow more slowly on this medium. After 10 days, colonies on PDA reached a diameter of 27 mm and produced a diffusible brownish-grey pigment. Colonies the SDA are 12 mm in diameter and grey-ochre in colour. The hyphae of M. granulomatis are septate and bear phialides that have single apical openings (monophialides) resembling a wine bottle. The conidia produced are in short, curved, chains, appearing glassy and smooth. Conidia are spherical-to-oval and 3.3-3.8 μm in length by 1.2-1.6 μm in width. The fungus produces a yeast-like stage in vitro on PDA after 3 days incubation at 35°C.
Pathogenicity
Metarhizium granulomatis is a rare fatal disease that infects veiled chameleons. Similar symptoms of disease are seen in M. viride. Common clinical signs seen in the veiled chameleons for this fungal disease are anorexia, hemorrhages in the tongue, necrotic toes, and ulcerative skin lesions. When observing the organs commonly infected, including the visceral organs, granulomas, glossitis, pharyngitis are seen. After death, cultures from the veiled lizard can be taken from the tongue, liver, lung, heart, kidney, small and large intestines. 1 to 3 mm spherical yeast-like yellow-to-white nodules are visible in the lung, liver and kidney.
Antifungal treatment
Treatment with nystatin and/or terbinafine may prevent further spreading or infection. When isolated most isolates susceptible to terbinafine, clotrimazole, amphotericin B, voriconazole and posaconazole. Although M. granulomatis is also resistant to some of the antifungals previously mentioned such as amphotericin B, voriconazole, fluconazole, and itraconazole.
References
Clavicipitaceae
Fungi described in 2014
Fungus species | Metarhizium granulomatis | [
"Biology"
] | 853 | [
"Fungi",
"Fungus species"
] |
58,485,186 | https://en.wikipedia.org/wiki/Chaetomium%20subspirale | Chaetomium subspirale is a fungus from the phylum Ascomycota. It was described by A. H. Chivers in 1912 in America. The species has sexual fruiting bodies that are ornamented with characteristic, coiled hairs giving it a wooly appearance. C. subspirale colonies are brown, which the characteristic hairs are also responsible for. It is commonly found in various soil and dung samples. C. subspirale produces the mycotoxin, oxaspirodion, which inhibits inducible TNF-a expression and inhibits the activation of the transcription factor NF-kappaB.
History and taxonomy
Professor A.H. Chivers recognized Chaetomium subspirale in 1912 in America through the course of his work on the genus Chaetomium. Through the examination of many successive generations and the cultivation of species from different sources on various media, Chivers was able to examine a large series of specimens from various herbaria and exsiccati. This examination allowed Chivers to provide his preliminary diagnosis of C. subspirale along with a number of other species within Chaetomium. X.W. Wang conducted a phylogenetic analysis of C. subspirale. Wang's findings have led her to propose the transfer of C. subspirale to the genus Humicola as H. subspiralis. MycoBank lists this new bionomial name as a synonym for C. subspirale.
Growth and morphology
Chaetomium subspirale has been recognized for having a daily growth rate of 2.5-3.5 μm for colonies. Canadian mycologist Dr. Adrian Carter observed a moderately fast growth rate of 3.0-3.5 mm/day in Czapek's medium and Leonian's medium and a growth rate of 3.0-4.0 mm/day for the tomato paste and oatmeal-based medium, Weitzman & Silvia-Hunter's agar.
Characteristic hair help to distinguish C. subspirale. The lateral hairs are short, straight and dark, with tightly coiled tips. The terminal slender is initially delicately coiled in a spiral and then elongated and twisted later. This gives the appearance of wool threads to the fungi. In comparison, the ascogonial coil are short, stipitate and irregularly coiled. Colonies of C. subspirale have an appearance of brown due to the erect, verrucose mycelial hairs. The ascomata, which are usually 200-280 μm, take 14 days to mature. In reflected light, they give a grey appearance with a brown wall of flattened, angular (7-12 μm) cells. With a brown and distinctly septate broad base of 2.5-3.5 μm, C. subspirale also has well-developed rhizoids, which can be up to 400 μm in length. C. subspirale's barrel shaped perithecia help to distinguish it from other species of Chaetomium.
Similar taxa
Chaetomium subspirale is similar to various other species in the genus Chaetomium. However it is possible to distinguish between the species due to differentiating characteristics. A few species that C. subspirale is similar to include C. homopilatum, C. ampullare, C. sphaerale, C. pulchellum, and C. semispirale. C. subspirale has smaller ascomata with a conical beak and larger ascospores than C. homopilatum. C. ampullare and C. sphaerale are easily distinguished from C. subspirale due to the larger ascospores and ascomata of C. subspirale. C. pluchellum morphologically resembles C. subspirale, however, C. pluchellum has more slender terminal perithecial hairs. Different ascospore sizes and colony morphology on Leonian's and Czapek's media help to differentiate C. subspirale from C. semispirale.
Habitat
Chivers states that C. subspirale is commonly found in various soil and dung samples. In terms of soil, C. subspirale has been found in cultures of various substrata from New England frequently. For dung samples, C. subspirale appears in various locations and various types of dung samples. In Ontario, Canada, it has been observed on paper and rabbit, cow and deer dung. In the US, C. subspirale has appeared on the dung of sheep, dog, good, deer and rabbit. In South America, it has been reported from chicken dung, while in the Isles of Shoals, it has been recorded to appear rat dung. It is also found on dung in The Netherlands and South America. Chivers identified C. subspirale on antelope dung in Kenya as well.
Industrial use
Significant research has revealed a large number of natural products derived from fungi that have potential for anti-inflammatory and anticancer properties for human cancer cells. Some compounds have even been tested in mouse models of human cancer to demonstrate their therapeutic benefits. Oxaspiradion is one of the fungi-derived natural products with an ability to aid in anti-inflammatory and anticancer measures. Isolated from C. subspirale, oxaspirodion inhibits inducible TNF-an expression and inhibits the activation of the transcription factor NF-kappaB.
Inflammatory diseases, such as, septic shock, rheumatoid arthritis and Crohn's disease, involve TNF-a as the main pro-inflammatory cytokine. Some new therapeutic approaches target the regulation of TNF-an expression. Rether et al. used a cell-based screening system to identify a low molecular weight compounds inhibitory to the induction of TNF-an expression from a large panel of mycelial cultures of basidiomycetes, ascomycetes. Rether et al. found that oxaspirodion derived from C. subspirale inhibited the expression of a TNF-a-driven luciferase reporter gene. The NF-kappaB pathway is considered a prototypical proinflammatory signaling pathway. Oxaspirodion inhibits the activation of the transcription factor NF-kappaB, leading to interest in its potential as an anticancer therapeutic.
References
subspirale
Fungi described in 1912
Fungus species | Chaetomium subspirale | [
"Biology"
] | 1,337 | [
"Fungi",
"Fungus species"
] |
58,485,652 | https://en.wikipedia.org/wiki/Sarocladium%20kiliense | Sarocladium kiliense is a saprobic fungus that is occasionally encountered as a opportunistic pathogen of humans, particularly immunocompromised and individuals. The fungus is frequently found in soil and has been linked with skin and systemic infections. This species is also known to cause disease in the green alga, Cladophora glomerata as well as various fruit and vegetable crops grown in warmer climates.
History and taxonomy
Sarocladium kiliense was renamed from Acremonium kiliense by Grütz in 1925, and it is particularly known as Cephalosporium acremonium in medical mycology. The name Cephalosporium was used to describe colorless molds with simple unbranched conidiophores and condiogenous cells bearing at the tip or head of the unicellular conidia. For all such molds that had these characteristics, many authors have been using the name C. acremonium. However, in 1971, Walter Gams kept the name A. kiliense to describe the fungus that were frequently found in soil and were associated with skin infections. Other similar fungus were put to a new species called A. strictum.
Gams divided Acremonium into three major sections: Acremonium, Gliomastix, and Nectriodea. Acremonium comprises four major clades: A. sclerotigenum, Sarocladium, A. curvulum, and A. breve. The genus Sarocladium contains multiple species previously treated in Acremonium and those that belong to the A. strictum and A. bacillisporum clades. Sarocladium species are noted for melanogenesis, a pathogenic factor in fungal disease, which is seen in S. kiliense.
Morphology
Colonies of S. kiliense have distinct characteristics, such as its colour, when grown on different medium. When the colonies are grown on glucose peptone agar at a temperature of , colonies can reach a diameter of 50 mm in one week. The colonies have a flat topography with a grey to an orange coloration. At the microscopic level, predominant features include balls of ellipsoidal conidia accumulated at the ends of long slender phialides and have oval chlamydospores. The conidiophores are long, straight, slightly tapering phialides, arising as side-branches on hyphae. At the end of the phialides are accumulated balls of slimy conidia with an ellipsoidall shape measuring 3-6 x 1.5 mm.
Colonies that are grown on sabouraud dextrose agar have a white coloration that later becomes pink during further incubation. Microscopically, the growth mostly has fasciculate mycelium giving rise to slender phialides. When the colonies are grown on oatmeal agar at a temperature of for 10 days, the isolates form poorly differentiated phialides, and single-cells, thick-walled uncoloured chlamydospores with chromophilic walls measuring 4-8 μm in diameter on the ends of hyphae and intervening in filaments. After 7 days of incubation, the chlamydospores become apparent although sclerotia remain absent.
Ecology and growth conditions
Sarocladium kiliense is a fungus that can be found throughout the world and have been seen in various European countries and warmer countries such as Egypt, India, and Nigeria. It is commonly isolated from the soil and seen in cereal fields, hay, apples, endosperm of rye grains, tomatoes, ground nuts, pineapples, and the soils of grass lands. In addition, Sarocladium kiliense have also been found to be an aerial contaminant. Isolates that are grown at higher temperatures have larger colonies than isolates grown at lower temperatures. When colonies are grown on glucose peptone agar at a temperature of , colonies can reach a diameter of 50 mm in one week. Colonies that are grown at on malt extract agar (MEA) form smaller colonies measuring 1.8-2.3 cm in diameter.
Pathogenicity
S. kiliense has been mainly known to be a human opportunistic pathogen and infections have been found to be more frequent in tropical countries. However, in individuals who are immunocompetent, the pathogenicity of S. kiliense is very low. Infection from the fungus usually occurs through a penetrating injury or open wounds that are exposed to the fungus. Since the fungi has the ability to go through the process of melanogenesis, one of the resulting infections is mycetoma. In patients who are immunocompetent, some of the local infections that may be seen are keratitis, endophthalmitis, onychomycosis, granuloma formation, or cutaneous skin infections. On the other hand, individuals who are immunocompromised and are infected by the fungus can face severe systemic infections and may develop peritonitis. In one study, it was found that S. kiliense was reported to invade the lungs. During the study, they were able to look at the blood and see narrow septate hyphae, cylindrical conidia, and other characteristics of S. kiliense. In addition to the lungs, it has also been known to invade the upper respiratory tract mucosa, sinuses, and conjunctiva.
Despite S. kiliense being mainly known as a human and animal pathogen, it also plays a role in plant diseases. It has been noted that they are pathogenic to the green algae, Cladophora glomerata, and isolated in plants such as apples, ground nuts, pineapple, lettuce and fennels. In 2016, in India, it was reported that S. kiliense was responsible for causing fruit rots in pears. When infected pears were examined, they displayed watery discolouration if the interior tissues without any browning. This was the first case that the fungi was known to cause the rotting in pears.
Diagnosis and treatment
Individuals who are infected by S. kiliense, diagnosis can be established by isolating the fungus from the infected region, culturing it, and identifying the fungus’ typical characteristics. Additionally, diagnosis can also be performed through the sequencing of the internal transcribed spacer (ITS) regions of the ribosomal RNA gene (rDNA). Currently, there is no optimal treatment for infections caused S. kiliense since it is resistant to almost all antifungal drugs. S. kiliense infections are difficult to treat and the outcomes are usually fatal. However, there have been successful reports of amphotericin B (AMB) during the treatment of the infection while other cases were unsuccessful. Moreover, the drug voriconazole has also been shown to have success in treating life threatening S. kiliense infections within immunocompromised patients.
Metabolism
In biotechnology, S. kiliense, which use to belong to the genus Cephalosporium produces cephalosporin C, an antibiotic similar to that of penicillin. Moreover, since S. kiliense use to belong to the genus Acremonium, it was noted that species from this genus can degrade polysaccharides, pectin, Carboxymethyl cellulose, xylans, and with S. kiliense mainly degrading starch. Furthermore, the fungus is also known to oxidize manganese in the soil and produce alkaline proteases and amylases.
References
Hypocreales
Fungi described in 2011
Fungus species | Sarocladium kiliense | [
"Biology"
] | 1,601 | [
"Fungi",
"Fungus species"
] |
58,485,912 | https://en.wikipedia.org/wiki/Sporoplasm | Sporoplasm is an infectious material present in the cytoplasm of various fungi-like organisms, such as members of class Microsporidia. Sporoplasm is defined as a mass of protoplasm that gives rise to or forms a spore. The protoplasmic body that is released as an infective amoebula from a cnidosporidian cyst.
Mode of infection
It is injected to host cell through a coiled polar tube which acts as a spring-like tubular extrusion mechanism. It is mainly involved in the asexual cycle of the organism.
Reproduction
Inside the host cell, the sporoplasm multiplies to generate meronts, cells with loosely organized organelles enclosed in a simple plasma membrane. Multiplication occurs either by merogony (binary fission) or schizogony (multiple fission) or plasmotomy (division of nucleus without relation to cytoplasm to produce multi-nucleated offspring).
References
Fungi
Microsporidia | Sporoplasm | [
"Biology"
] | 214 | [
"Fungi"
] |
58,486,357 | https://en.wikipedia.org/wiki/Soft%20configuration%20model | In applied mathematics, the soft configuration model (SCM) is a random graph model subject to the principle of maximum entropy under constraints on the expectation of the degree sequence of sampled graphs. Whereas the configuration model (CM) uniformly samples random graphs of a specific degree sequence, the SCM only retains the specified degree sequence on average over all network realizations; in this sense the SCM has very relaxed constraints relative to those of the CM ("soft" rather than "sharp" constraints). The SCM for graphs of size has a nonzero probability of sampling any graph of size , whereas the CM is restricted to only graphs having precisely the prescribed connectivity structure.
Model formulation
The SCM is a statistical ensemble of random graphs having vertices () labeled , producing a probability distribution on (the set of graphs of size ). Imposed on the ensemble are constraints, namely that the ensemble average of the degree of vertex is equal to a designated value , for all . The model is fully parameterized by its size and expected degree sequence . These constraints are both local (one constraint associated with each vertex) and soft (constraints on the ensemble average of certain observable quantities), and thus yields a canonical ensemble with an extensive number of constraints. The conditions are imposed on the ensemble by the method of Lagrange multipliers (see Maximum-entropy random graph model).
Derivation of the probability distribution
The probability of the SCM producing a graph is determined by maximizing the Gibbs entropy subject to constraints and normalization . This amounts to optimizing the multi-constraint Lagrange function below:
where and are the multipliers to be fixed by the constraints (normalization and the expected degree sequence). Setting to zero the derivative of the above with respect to for an arbitrary yields
the constant being the partition function normalizing the distribution; the above exponential expression applies to all , and thus is the probability distribution. Hence we have an exponential family parameterized by , which are related to the expected degree sequence by the following equivalent expressions:
References
Random graphs | Soft configuration model | [
"Physics",
"Mathematics"
] | 414 | [
"Graph theory",
"Mathematical relations",
"Random graphs",
"Statistical ensembles",
"Statistical mechanics"
] |
58,486,553 | https://en.wikipedia.org/wiki/Fat%20storage-inducing%20transmembrane%20protein%201 | Fat storage-inducing transmembrane protein 1 is a protein that in humans is encoded by the FITM1 gene.
Function
FIT1 belongs to an evolutionarily conserved family of proteins involved in fat storage (Kadereit et al., 2008 [PubMed 18160536]).[supplied by OMIM, May 2008].
References | Fat storage-inducing transmembrane protein 1 | [
"Chemistry"
] | 74 | [
"Biochemistry stubs",
"Protein stubs"
] |
58,487,522 | https://en.wikipedia.org/wiki/Preconditioned%20Crank%E2%80%93Nicolson%20algorithm | In computational statistics, the preconditioned Crank–Nicolson algorithm (pCN) is a Markov chain Monte Carlo (MCMC) method for obtaining random samples – sequences of random observations – from a target probability distribution for which direct sampling is difficult.
The most significant feature of the pCN algorithm is its dimension robustness, which makes it well-suited for high-dimensional sampling problems. The pCN algorithm is well-defined, with non-degenerate acceptance probability, even for target distributions on infinite-dimensional Hilbert spaces. As a consequence, when pCN is implemented on a real-world computer in large but finite dimension N, i.e. on an N-dimensional subspace of the original Hilbert space, the convergence properties (such as ergodicity) of the algorithm are independent of N. This is in strong contrast to schemes such as Gaussian random walk Metropolis–Hastings and the Metropolis-adjusted Langevin algorithm, whose acceptance probability degenerates to zero as N tends to infinity.
The algorithm as named was highlighted in 2013 by Cotter, Roberts, Stuart and White, and its ergodicity properties were proved a year later by Hairer, Stuart and Vollmer. In the specific context of sampling diffusion bridges, the method was introduced in 2008.
Description of the algorithm
Overview
The pCN algorithm generates a Markov chain on a Hilbert space whose invariant measure is a probability measure of the form
for each measurable set , with normalising constant given by
where is a Gaussian measure on with covariance operator and is some function. Thus, the pCN method applied to target probability measures that are re-weightings of a reference Gaussian measure.
The Metropolis–Hastings algorithm is a general class of methods that try to produce such Markov chains , and do so by a two-step procedure of first proposing a new state given the current state and then accepting or rejecting this proposal, according to a particular acceptance probability, to define the next state . The idea of the pCN algorithm is that a clever choice of (non-symmetric) proposal for a new state given might have an associated acceptance probability function with very desirable properties.
The pCN proposal
The special form of this pCN proposal is to take
or, equivalently,
The parameter is a step size that can be chosen freely (and even optimised for statistical efficiency). One then generates and sets
The acceptance probability takes the simple form
It can be shown that this method not only defines a Markov chain that satisfies detailed balance with respect to the target distribution , and hence has as an invariant measure, but also possesses a spectral gap that is independent of the dimension of , and so the law of converges to as . Thus, although one may still have to tune the step size parameter to achieve a desired level of statistical efficiency, the performance of the pCN method is robust to the dimension of the sampling problem being considered.
Contrast with symmetric proposals
This behaviour of pCN is in stark contrast to the Gaussian random walk proposal
with any choice of proposal covariance , or indeed any symmetric proposal mechanism. It can be shown using the Cameron–Martin theorem that for infinite-dimensional this proposal has acceptance probability zero for -almost all and . In practice, when one implements the Gaussian random walk proposal in dimension , this phenomenon can be seen in the way that
for fixed , the acceptance probability tends to zero as , and
for a fixed desired positive acceptance probability, as .
References
Monte Carlo methods
Markov chain Monte Carlo
Sampling techniques | Preconditioned Crank–Nicolson algorithm | [
"Physics"
] | 720 | [
"Monte Carlo methods",
"Computational physics"
] |
58,487,990 | https://en.wikipedia.org/wiki/Dimethylstilbestrol | Dimethylstilbestrol (DMS) is a nonsteroidal estrogen of the stilbestrol group related to diethylstilbestrol which was never marketed. It is a so-called "weak", "impeded", or "short-acting" estrogen similarly to estriol and meso-butoestrol. The affinity of DMS for the ER was reported as about 10% of that of estradiol. For comparison, diethylstilbestrol had 140% of the affinity of estradiol for the ER.
The endometrial proliferation dose of DMS in women is 20 mg. A single 12 mg intramuscular injection of DMS has a duration of approximately 12 days in humans.
References
Abandoned drugs
4-Hydroxyphenyl compounds
Stilbenoids
Synthetic estrogens | Dimethylstilbestrol | [
"Chemistry"
] | 177 | [
"Drug safety",
"Abandoned drugs"
] |
58,488,142 | https://en.wikipedia.org/wiki/Upper%20Colorado%20water%20resource%20region | The Upper Colorado water resource region is one of 21 major geographic areas, or regions, in the first level of classification used by the United States Geological Survey to divide and sub-divide the United States into successively smaller hydrologic units. These geographic areas contain either the drainage area of a major river, or the combined drainage areas of a series of rivers.
The Upper Colorado region, which is listed with a 2-digit hydrologic unit code (HUC) of 14, has an approximate size of , and consists of 8 subregions, which are listed with the 4-digit HUCs 1401 through 1408.
This region includes the drainage of: (a) the Colorado River Basin above the Lee Ferry compact point which is one mile below the mouth of the Paria River; and (b) the Great Divide closed basin. Includes parts of Arizona, Colorado, New Mexico, Utah, and Wyoming.
List of water resource subregions
See also
List of rivers in the United States
References
Lists of drainage basins
Drainage basins
Watersheds of the United States
Regions of the United States
Resource
Water resource regions | Upper Colorado water resource region | [
"Environmental_science"
] | 222 | [
"Hydrology",
"Drainage basins"
] |
58,489,311 | https://en.wikipedia.org/wiki/Lower%20Colorado%20water%20resource%20region | The Lower Colorado water resource region is one of 21 major geographic areas, or regions, in the first level of classification used by the United States Geological Survey to divide and sub-divide the United States into successively smaller hydrologic units. These geographic areas contain either the drainage area of a major river, or the combined drainage areas of a series of rivers.
The Lower Colorado region, which is listed with a 2-digit hydrologic unit code (HUC) of 15, has an approximate size of , and consists of 8 subregions, which are listed with the 4-digit HUCs 1501 through 1508.
This region includes the drainage within the United States of: (a) the Colorado River Basin below the Lee Ferry compact point which is one mile below the mouth of the Paria River; (b) streams that originate within the United States and ultimately discharge into the Gulf of California; and (c) the Animas Valley, Willcox Playa, and other smaller closed basins. Includes parts of Arizona, California, Nevada, New Mexico, and Utah.
List of water resource subregions
See also
List of rivers in the United States
Water resource region
References
Lists of drainage basins
Drainage basins
Watersheds of the United States
Regions of the United States
Resource
Water resource regions | Lower Colorado water resource region | [
"Environmental_science"
] | 260 | [
"Hydrology",
"Drainage basins"
] |
58,489,414 | https://en.wikipedia.org/wiki/Killam%20Prize | The Killam Prize (previously the Izaak Walton Killam Memorial Prize) was established according to the will of Dorothy J. Killam to honour the memory of her husband Izaak Walton Killam.
Five Killam Prizes, each having a value of $100,000, were awarded annually by the Canada Council for the Arts to eminent Canadian researchers who distinguish themselves in the fields of social sciences, humanities, natural sciences, health sciences, or engineering.
In August 2021, the Canada Council announced it would transition the administration of the Killam program to the National Research Council Canada (NRC) by March 2022.
The restructured Killam Program was officially launched under the administration of the NRC in April 2022. It is now called the National Killam Program and consists of the Killam Prizes and the Dorothy Killam Fellowships.
Recipients
See also
List of medicine awards
List of social sciences awards
References
External links
Killam Laureates website
Canada Council for the Arts Killam Prizes webpage
Transition to the National Research Council of Canada from the Canada Council for the Arts
Canadian science and technology awards
fr:Prix Izaak-Walton-Killam | Killam Prize | [
"Technology"
] | 232 | [
"Science and technology awards",
"Science and technology award winners"
] |
58,489,514 | https://en.wikipedia.org/wiki/Malaysia%20Design%20Archive | The Malaysia Design Archive (MDA) is a non-profit private organization based in Kuala Lumpur oriented towards various projects to document, discuss, and preserve Malaysia's visual culture. Its leading team members are Ezrena Marwan, Jac sm Kee, and Simon Soon. Their core material collection are graphic materials tracing the development of Malaysia from the period before independence (1957) until current times. The collection is housed at their office in the Zhongshan Building, Kuala Lumpur. Access to the collection on site is free and also available via their official website as well as an online database.
See also
List of tourist attractions in Malaysia
References
External links
2008 establishments in Malaysia
Archives in Malaysia
Buildings and structures in Kuala Lumpur
Culture of Kuala Lumpur
Business and industry archives
Design history | Malaysia Design Archive | [
"Engineering"
] | 157 | [
"Design history",
"Design"
] |
58,490,342 | https://en.wikipedia.org/wiki/Falck-Hillarp%20method%20of%20fluorescence | The Falck-Hillarp method of fluorescence (the F-H method) is a technique that makes it possible to demonstrate and study, with unique precision and susceptibility, certain monoamines, among those the three catecholamines dopamine, noradrenaline, and adrenaline, as well as serotonin and related substances.
The method is based on the important and decisive discovery that these compounds are able to react with formaldehyde – in near complete absence of water – to form fluorophores, i.e. molecules that, when irradiated with light invisible to the eye, will emit visible light. This happens in a “dry” state, without extracting the monoamines from the cells during the entire procedure, a process that starts with separation of a tissue sample and ends with a thin tissue slice that can be examined in a fluorescence microscope.
The F-H method allowed, for the first time, the examiner to watch these monoamines light up in the microscope and to precisely determine in which cells they were present, and thereby understanding their functions. The method was developed by Bengt Falck and Nils-Åke Hillarp in the 1960s at the Department of Histology, University of Lund. For intense neurobiological research it became possible to demonstrate the presence of monoamines in nerve cells belonging to the central and the peripheral nervous system and for the first time comprehend that these substances act as signal substances, i.e. transmitters.
The initial publication, written already in 1961, described a wide-ranging examination of nerves supplying a large number of organs in the body. This work validated the concept of Ulf von Euler, the Nobel prize winner, that noradrenaline is the signal substance in peripheral autonomic nerves. In the same year, this first publication was followed by an explanation of the chemical background of the F–H method.
Very thin membranes, such as the rat iris or mesentery, do not have to be sectioned for microscopic studies but may simply be spread on glass, dried, and then exposed to gaseous formaldehyde for subsequent study with a fluorescence microscope.
The publication on the chemical background was later named among "The 200 Most-Cited Papers of All Time".
In 2012, the Faculty of Medicine at the University of Lund arranged a symposium “From Nerve to Pills” celebrating the 50th anniversary of the initial publication of the F-H method.
References
External links
The Falck-Hillarp Fluorescence Method,
Biochemistry methods | Falck-Hillarp method of fluorescence | [
"Chemistry",
"Biology"
] | 525 | [
"Biochemistry methods",
"Biochemistry"
] |
58,490,571 | https://en.wikipedia.org/wiki/Slicer%20%283D%20printing%29 | A slicer is a toolpath generation software used in 3D printing. It facilitates the conversion of a 3D object model to specific instructions for the printer. The slicer converts a model in STL (stereolithography) format into printer commands in G-code format. This is particularly usable in fused filament fabrication and other related 3D printing processes.
Features
A slicer initially segments the object as a stack of flat layers. It then describes these layers through linear movements of the 3D printer's extruder, the fixation laser, or an equivalent component. All these movements, together with some specific printer commands like the ones to control the extruder temperature or bed temperature, are ultimately compiled in the G-code file. This file can then be transferred to the printer for execution.
Additional features of slicer are listed below:
Infill: Printing solid objects requires a significant amount of material (such as filament) and time. To mitigate this, slicers can automatically convert solid volumes to hollow ones, thereby saving costs and reducing print time. These hollow objects can be reinforced with internal structures, like internal walls, to enhance robustness. The proportion of these structures, known as 'infill density', is a key parameter that can be adjusted in the slicer.
Supports: Since most 3D printing processes build objects layer by layer, from the bottom up, each new layer is deposited directly on top of the previous one. Consequently, every part of the object must, to some extent, rest on another part. For layers that are 'floating'—for example, the flat roof of a house or a horizontally extended arm in a figure—the slicer can automatically add supports. These supports are designed to touch the object in a manner that allows for easy detachment upon the completion of the object's production.
Rafts, skirts and brims: The printing of the first object layer, which contacts the printer bed, presents unique challenges, such as adherence issues, surface rugosity, and the smooth deposition of the initial filament. To mitigate these problems, the slicer can automatically add detachable structures. Common types of these base structures include:
A skirt: A single band encircling the object's base, without touching it.
A brim: Multiple lines of filament around the base of the object, touching but not underneath it, and extending outward.
A raft: Several layers of material forming a detachable base on which the object is printed.
List of slicer software
There is a diverse array of slicer applications available, including many that are free and open-source. Some of the most commonly used ones include:
References
3D printing
Computer printers
DIY culture
Industrial design
Industrial processes | Slicer (3D printing) | [
"Engineering"
] | 561 | [
"Industrial design",
"Design engineering",
"Design"
] |
78,142,100 | https://en.wikipedia.org/wiki/Soterenol | Soterenol (), also known as soterenol hydrochloride (; developmental code name MJ-1992) in the case of the hydrochloride salt, is a drug of the phenethylamine family described as an adrenergic, bronchodilator, and antiasthmatic which was never marketed. It is an analogue of salbutamol and acts as a β-adrenergic receptor agonist. The drug was first developed in 1964 and was first described in the literature by 1967.
References
Abandoned drugs
Amines
Antiasthmatic drugs
Beta-adrenergic agonists
Bronchodilators
Phenylethanolamines
Sulfonamides
Sympathomimetics
Isopropylamino compounds | Soterenol | [
"Chemistry"
] | 163 | [
"Drug safety",
"Functional groups",
"Amines",
"Bases (chemistry)",
"Abandoned drugs"
] |
78,142,178 | https://en.wikipedia.org/wiki/Meluadrine | Meluadrine (), also known as meluadrine tartrate (; developmental code name HSR-81) in the case of the tartrate salt, is a sympathomimetic and β2-adrenergic receptor agonist which was studied as a tocolytic drug but was never marketed. It was first described in the literature by 1994. The drug is also known as (R)-4-hydroxytulobuterol and is an active metabolite of tulobuterol.
References
Abandoned drugs
Beta2-adrenergic agonists
Chloroarenes
Enantiopure drugs
Human drug metabolites
Phenylethanolamines
Sympathomimetics
Tert-butyl compounds | Meluadrine | [
"Chemistry"
] | 161 | [
"Stereochemistry",
"Drug safety",
"Enantiopure drugs",
"Human drug metabolites",
"Chemicals in medicine",
"Abandoned drugs"
] |
78,142,324 | https://en.wikipedia.org/wiki/Norbudrine | Norbudrine (; developmental code name RD-9338), also known as norbutrine () or as N-cyclobutylnoradrenaline, is a drug of the phenethylamine and catecholamine families described as a sympathomimetic and bronchodilator which was never marketed. It is the N-cyclobutyl analogue of norepinephrine (noradrenaline). The drug was first described in the literature by 1966.
References
Abandoned drugs
Bronchodilators
Catecholamines
Cyclobutyl compounds
Phenylethanolamines
Sympathomimetics | Norbudrine | [
"Chemistry"
] | 144 | [
"Drug safety",
"Abandoned drugs"
] |
78,142,570 | https://en.wikipedia.org/wiki/Social%20acceleration | Social acceleration is a sociological concept of time in late modernity developed by German sociologist Hartmut Rosa. It was featured in his book Beschleunigung. Die Veränderung der Zeitstrukturen in der Moderne.Social acceleration describes a frenetic sense of time caused by the increase in technological advancement since the Industrial Revolution. Rosa argues that advances in communication, transportation, and production have made things happen faster, creating new expectations of efficiency and speed in all areas of life in ways that alienate people from the world.
Abstract and linear time
In Rosa's view, a medieval peasant's life was organized around nature's linear time, such as seasons and day-night cycles. Work and life tasks were dictated by nature, meaning there was little expectation for rapid change or constant activity.
In contrast, Rosa argues modern life is governed by abstract time. Abstract time structures are defined according to the task in question. Abstract time is not bound by natural linear time, but by new temporal structures, such as schedules, deadlines, or even very short windows of time such as stock transactions, which can be executed in microseconds. Abstract time treats time as a resource to be continually redefined, controlled and divided. Therefore, instead of stability, late modern subjects experience frenetic change, intensification, and pressure to keep up.
The term does not merely refer to the widely held view that modernity is characterised by a rapid pace of life. Rather, it refers to “an increase in quantity per unit of time”. Therefore, it describes a situation where the potential number of distinct experience episodes in a given timeframe has rapidly increased. Rosa suggests this creates a “contraction of the present,” described as “a decrease of the length of time for which there prevail secure expectations regarding the stability of the circumstances of action”.
Dynamic stabilization
As a phenomenologist, Rosa claims that social acceleration is present on both an international and individual level. For instance, he states that for a government's credit rating to remain to same they must accelerate the rate of production. This logic of needing to speed up just to stay where you are Rosa terms dynamic stabilization. On the individual level, social acceleration has led to burnout, since the number of possible tasks and commitments far exceeds the amount of time available. This creates a constant pressure to control, parameterise, and optimise every moment, leading individuals to feel perpetually overwhelmed and incapable of keeping pace, an experience he calls frenetic standstill.
Impact of technology
Email greatly expanded the number of messages that could be transmitted, removing the time limitations of traditional mail. However, this transition brought about new challenges, including the demand for quick replies and the potential for information overload. Additionally, social acceleration is evident on streaming services and social media trends, intensifying the enormous pressure to stay current with ever-evolving content and interactions.
Rosa views dynamics like these as demonstrating how social acceleration normalises a mode of aggression to the world, one that insists that resources be available, accessible and attainable. He claims that this mode of aggression towards the world is present in every aspect of life, from trade, to political discourse, and social interaction.
Consequences of acceleration
Rosa suggests that this relentless acceleration not only leads to burnout but also disrupts our ability to form meaningful relationships with the world, causing alienation. This difference between linear time and abstract time is key to social acceleration.
On an individual level the result is a profound shift in everyday life, with modern people feeling a constant race against time, unlike the slower pace that medieval subjects experienced, in which hard work took up most of their lives, but for whom the number of possible tasks were clearly defined. On a policy level, the rate of technological and social change is said to create an inertia effect where policymakers cannot keep up with challenging sociopolitical changes as they happen. Therefore, regulation of technologies like AI are perpetually behind the actual rate of technological change.
Rosa uses the term resonance to describe moments of brief respite from social acceleration.
See also
Overwork
Slow movement
References
Sociology
Postmodernism
German sociologists | Social acceleration | [
"Biology"
] | 847 | [
"Behavioural sciences",
"Behavior",
"Sociology"
] |
78,142,608 | https://en.wikipedia.org/wiki/Trecadrine | Trecadrine () is a drug that was originally developed as an anti-ulcer agent but was found to act as a β3-adrenergic receptor agonist with potential anti-obesity and anti-diabetic properties. It is selective for the β3-adrenergic receptor, lacking activity at the β1- and β2-adrenergic receptors. The drug is orally active. Structurally, trecadrine is a substituted β-hydroxyamphetamine and derivative of β-hydroxy-N-methylamphetamine (ephedrine, pseudoephedrine) with a tricyclic moiety attached at the amine.
References
Abandoned drugs
Anti-diabetic drugs
Anti-obesity drugs
Beta3-adrenergic agonists
Drugs for acid-related disorders
Methamphetamines
Sympathomimetics
Tricyclic compounds
Phenethylamines
Ethanolamines
Dibenzocycloheptenes | Trecadrine | [
"Chemistry"
] | 206 | [
"Drug safety",
"Abandoned drugs"
] |
78,142,655 | https://en.wikipedia.org/wiki/Churchill%20Residence | The Churchill Residence or Churchill Residency is a residential skyscraper in Dubai, United Arab Emirates. Built between 2006 and 2010, th building stands at tall with 61 floors and is the current 84th tallest building in Dubai.
History
Architecture
Created by Design and Architecture Bureau (DAR), the tower is located in the Business Bay district of Dubai. It is part of a mixed-use complex shared with a lower-rise 42-floor commercial building with which summes up over 2.5 million square feet of built-up area. The complex provide facilities such as a swimming pool, gym, sauna, tennis and basketball courts, mini golf courses, and a playground. It also provides landscaped plazas provided in the Courtyard. This feature incorporates contemporary architectural elements with premium amenities, whereas the Podium serves as a distinct feature connecting the residential towers and offering covered paths, fountains, and pedestrian-friendly pathways.
The ambience of the complex was designed to provide identity for the project and create a highly conducive environment and infrastructure for businesses from around the world that wish to establish their local, regional and international headquarters here at Business Bay.
Together with the Al Kazim Towers, the Churchill tower resembles New York City's Chrysler Building roof geometry.
See also
List of tallest buildings in Dubai
List of tallest buildings in the United Arab Emirates
List of tallest residential buildings in Dubai
References
External links
Churchill Residence at SKYDB
Churchill Residency at SkyscraperPage
Churchill Residence at SKYDB
Residential skyscrapers in Dubai
Residential buildings completed in 2010
Buildings and structures completed in 2010
2010 establishments in the United Arab Emirates
Residential skyscrapers
Postmodern architecture
Pencil towers | Churchill Residence | [
"Engineering"
] | 326 | [
"Postmodern architecture",
"Architecture"
] |
78,142,980 | https://en.wikipedia.org/wiki/Tinofedrine | Tinofedrine (; developmental code name D-8955, proposed brand name Novocebrin), also known as N-(3,3-di-3-thienyl)-2-propenyl)norephedrine, is a sympathomimetic and cerebral vasodilator of the amphetamine family which was never marketed. It is a derivative of norephedrine and an analogue of related agents like oxyfedrine, buphenine (nylidrin), and isoxsuprine. The drug was first described in the literature by 1978.
References
Abandoned drugs
Beta-Hydroxyamphetamines
Enantiopure drugs
Sympathomimetics
Thiophenes
Vasodilators
Cerebral vasodilators | Tinofedrine | [
"Chemistry"
] | 168 | [
"Pharmacology",
"Stereochemistry",
"Drug safety",
"Enantiopure drugs",
"Medicinal chemistry stubs",
"Pharmacology stubs",
"Abandoned drugs"
] |
78,143,045 | https://en.wikipedia.org/wiki/Clofenetamine | Clofenetamine (), also known as phenoxethamine or as Keithon, is a drug described as a tranquilizer, antihistamine, anticholinergic, and antiparkinsonian agent. It is a derivative of diphenhydramine and is closely structurally related to mephenhydramine, chlorphenoxamine, and embramine, among other drugs. Clofenetamine was discovered by Searle in the 1940s and was first described in the literature by 1956.
References
4-Chlorophenyl compounds
Abandoned drugs
Diethylamino compounds
Antiparkinsonian agents
Antihistamines
Anticholinergics
Ethanolamines | Clofenetamine | [
"Chemistry"
] | 147 | [
"Drug safety",
"Abandoned drugs"
] |
78,143,091 | https://en.wikipedia.org/wiki/Etaminile | Etaminile (; developmental code name OM-977) is a drug described as an antitussive (cough suppressant) which was never marketed. It was first described in the literature by 1963.
References
Abandoned drugs
Dimethylamino compounds
Antitussives
Nitriles | Etaminile | [
"Chemistry"
] | 59 | [
"Nitriles",
"Drug safety",
"Functional groups",
"Abandoned drugs"
] |
78,143,211 | https://en.wikipedia.org/wiki/Fotretamine | Fotretamine (), also known as fotrin, is an alkylating antineoplastic and immunosuppressant. The drug entered clinical trials in the Soviet Union. It was first described in the literature by 1972.
See also
List of Russian drugs
References
Abandoned drugs
Alkylating antineoplastic agents
Drugs in the Soviet Union
Immunosuppressants
4-Morpholinyl compounds
Russian drugs
Phosphazenes
1-Aziridinyl compounds | Fotretamine | [
"Chemistry"
] | 102 | [
"Pharmacology",
"Drug safety",
"Medicinal chemistry stubs",
"Pharmacology stubs",
"Abandoned drugs"
] |
78,143,396 | https://en.wikipedia.org/wiki/Clorprenaline | Clorprenaline (, , ), also known as isoprophenamine and known as clorprenaline hydrochloride (, ) in the case of the hydrochloride salt, is a sympathomimetic and bronchodilator medication which is marketed in Japan. It acts as a β-adrenergic receptor agonist or as a β-sympathomimetic. Brand names of clorprenaline in Japan are numerous and include Asnormal, Bazarl, Bronchon, Clopinerin, Conselt, Cosmoline, Fusca, Kalutein, Pentadoll, Restanolon, and Troberin. The drug was first described in the literature by 1956.
References
Beta-adrenergic agonists
Bronchodilators
Chloroarenes
Phenylethanolamines
Sympathomimetics
Isopropylamino compounds | Clorprenaline | [
"Chemistry"
] | 201 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
78,143,433 | https://en.wikipedia.org/wiki/Barbette%20ship | The barbette ship was a type of ironclad warship that was built by several navies between the 1860s and 1890s. The defining characteristic was the use of armored barbettes to partially protect the ship's main battery guns, rather than heavy gun turrets or inflexible box batteries.
Development
Following the introduction of ironclad warships in the early 1860s, naval designers grappled with the problem of mounting heavy guns in the most efficient way possible. The first generation of ironclads employed the same broadside arrangement as the old ship of the line, but it was not particularly effective for ahead or stern fire. This was particularly important to designers, since the tactic of ramming was revived following its successful employment at the decisive Austrian victory at the Battle of Lissa in 1866. Ramming required a ship to steam directly at its opponent, which greatly increased the importance of end-on fire. Designers such as Cowper Phipps Coles and John Ericsson designed the first gun turrets in the 1860s, which gave the guns a wide field of fire. These turrets were exceedingly heavy, which required them to be placed low in the ship to reduce top-weight—and produced a dangerous tendency to capsize in heavy seas, amply demonstrated by the loss of and Coles himself with the ship in a gale in 1870.
In the 1870s, designers began to experiment with an en barbette type of mounting. The barbette was a fixed armored enclosure protecting the gun. The barbette could take the form of a circular or elongated ring of armor around the rotating gun mount over which the guns (possibly fitted with a gun shield) fired. The barbette system reduced weight considerably, since the machinery for the rotating gun mount, along with the mount itself, was much lighter than that required for the gun house of a turret. The savings in weight could then be passed on to increase armor protection for the hull, improve coal storage capacity, or to install larger, more powerful engines. In addition, because barbettes were lighter, they could be placed higher in the ship without jeopardizing stability, which improved their ability to be worked in heavy seas that would have otherwise rendered turrets unusable. This also permitted a higher freeboard, which also improved seakeeping.
Ironclads equipped with barbettes were referred to as "barbette ships" much like their contemporaries, turret ships and central battery ships, which mounted their heavy guns in turrets or in a central armored battery. Many navies experimented with all three types in the 1870s and 1880s, including the British Admiral-class battleships, the French s, the Italian s, and the German s, all of which employed barbettes to mount their heavy guns. All of these navies also built turret and or central battery ships during the same period, though none had a decisive advantage over the other. The British and the Russian navies experimented with using disappearing guns afloat, including on the British and the Russian ironclad . They were not deemed particularly successful and were not repeated.
Replacement
In the late 1880s, the debate between barbette or turret mounts was finally settled. The , mounted their guns in barbettes, but the follow-on design, the , adopted a new mounting that combined the benefits of both kinds of mounts. A heavily armored, rotating gun house was added to the revolving platform, which kept the guns and their crews protected. The gun house was smaller and lighter than the old-style turrets, which still permitted placement higher in the ship and the corresponding benefits to stability and seakeeping. This innovation gradually became known simply as a turret, though the armored tube that held the turret substructure, which included the shell and propellant handling rooms and the ammunition hoists, was still referred to as a barbette. These ships were the prototype of the so-called pre-dreadnought battleships, which proved to be broadly influential in all major navies over the next fifteen years.
Use in service
Ships equipped with barbette mountings did not see a great deal of combat, owing to the long period of relative peace between their appearance in the 1870s and their obsolescence in the 1890s. Some barbette ships saw action during the British Bombardment of Alexandria in 1882, and the participated in the Battle of Fuzhou during the Sino-French War in 1884. The two Chinese ironclads, and , that took part in the Battle of the Yalu River during the First Sino-Japanese War in 1894, carried their main battery in barbettes, though they were equipped with extensive gun shields that resembled turrets. The shields were nevertheless only proof against small-arms fire. Three of their opponents at the Yalu River, the Japanese s, also mounted their guns in open barbettes.
Those barbette ships that survived into World War I were typically used only for secondary purposes. For example, the French was used as a repair ship for submarines and torpedo boats, while the German was employed as a torpedo training ship. A handful of barbette ships did see action during the war, including the British , which bombarded German positions in Flanders in 1914 and 1915.
Notes
References
Warships
Ship types
Shipbuilding | Barbette ship | [
"Engineering"
] | 1,058 | [
"Shipbuilding",
"Marine engineering"
] |
78,144,645 | https://en.wikipedia.org/wiki/Third-pound%20burger | The third-pound burger is a hamburger made with a patty that weighs one-third of a pound (approximately 5.3 ounces or 150 grams) before cooking. It is larger than the more common quarter-pound burger (4 ounces or 113 grams) typically sold by fast-food chains. The third-pound burger gained notable attention in the 1980s due to an ill-fated marketing campaign by A&W Restaurants in the United States, which has since become a case study in consumer behavior and market communication.
History
In the 1980s, A&W, under then-owner A. Alfred Taubman, sought to challenge McDonald's highly successful Quarter Pounder by introducing a larger, higher-quality hamburger. The campaign, called "Third is the Word," was designed to promote A&W's third-pound burger as a better value for the same price as McDonald's quarter-pound burger. Despite the promise of more meat for the same price, the campaign failed to resonate with consumers.
Taubman recounted the experience in his book, Threshold Resistance. He described how the company aggressively marketed the third-pound burger through TV and radio promotional spots, but sales remained lackluster. Confused as to why the burger was not selling, Taubman hired a market research firm to conduct a study.
Marketing failure
The research firm organized focus groups to understand why A&W's third-pound burgers weren't competing well with McDonald's Quarter Pounders. The results revealed a surprising source of consumer resistance: many participants mistakenly believed that one-third of a pound was smaller than one-fourth (quarter) of a pound. Focus group participants expressed confusion over the price, asking why they should pay the same amount for a "smaller" third-pound burger.
This misunderstanding stemmed from consumers focusing on the numbers "3" and "4," leading them to conclude that one-third (1/3) was smaller than one-fourth (1/4), even though the opposite is true.
A similar account was reported by The New York Times in 2014, which cited the A&W third-pound burger as one of the most vivid examples of consumer arithmetic failure. In taste tests, customers actually preferred A&W's third-pound burger to McDonald's Quarter Pounder, and it was less expensive. However, consumers misunderstood the fraction, believing they were being overcharged for a smaller burger.
According to a CBC report, more than half of the people surveyed about the burger said they didn't buy it because they thought they were getting less meat for the same price as McDonald's Quarter Pounder. The New York Times echoed this sentiment, noting that the larger number "4" in "¼" confused customers, making them think it was a better deal than "⅓".
Corporate Response
Despite the confusion and failure of the campaign, Taubman later reflected on the incident, stating that "Sometimes the messages we send to our customers through marketing and sales inf ormation are not as clear and compelling as we think they are."
Legacy
The failure of A&W's third-pound burger campaign has since become a widely discussed example of how marketing messages can be misunderstood, and how consumer numeracy plays a role in decision-making. The story is often shared in the context of marketing, advertising, and consumer behavior studies as a cautionary tale about the importance of clear communication.
In retrospect, the third-pound burger incident highlights how companies need to account for consumer perceptions and potential misunderstandings when crafting marketing strategies. Some analysts also suggest that more effective education or clearer messaging might have salvaged the campaign.
Cultural impact
The story of the third-pound burger has been referenced in business literature, marketing case studies, and even in popular culture as an example of how numbers and fractions can be confusing for the average consumer. The A&W third-pound burger incident remains a significant lesson in the history of advertising, emphasizing the gap between consumer logic and numerical understanding.
Resurgence
In recent years, A&W has embraced the anecdote as part of its brand identity. The chain occasionally revisits the story in marketing material to engage with nostalgic customers and leverage the viral nature of the story in the digital age. The third-pound burger is now seen as part of A&W's history.
See also
Quarter Pounder
References
Fast food hamburgers
Consumer behaviour
Mathematics and culture | Third-pound burger | [
"Biology"
] | 901 | [
"Behavior",
"Consumer behaviour",
"Human behavior"
] |
78,144,994 | https://en.wikipedia.org/wiki/The%20Journal%20of%20The%20Textile%20Institute | The Journal of The Textile Institute is a peer-reviewed scientific journal that covers research and advancements in the field of textile science and textile engineering. The journal's editor-in-chief is Xungai Wang. It was established in 1910 and is published by Taylor & Francis on behalf of the Textile Institute, a professional body for individuals working in textiles, clothing, and footwear industries.
Abstracting and indexing
The journal is abstracted and indexed in major databases including Inspec,Scopus, Web of Science, and Google Scholar.
According to the Journal Citation Reports, the journal has a 2023 impact factor of 1.8.
References
External links
Taylor & Francis academic journals
English-language journals
Textile journals
Academic journals established in 1910
Hybrid open access journals
Textile industry | The Journal of The Textile Institute | [
"Materials_science"
] | 157 | [
"Materials science stubs",
"Materials science journals",
"Materials science journal stubs",
"Textile journals"
] |
78,145,261 | https://en.wikipedia.org/wiki/Penflufen | Penflufen is a fungicide which was produced and patented by Bayer AG in 2006 and is used for crop protection from fungi. Penflufen is a new generation succinate-dehydrogenase inhibitor, which blocks the electron transport at complex II in the mitochondrial respiration chain. The European Chemical Agency (ECHA) has also approved the use of penflufen as a biocide in wood preservation while labelling it to be a suspected carcinogen.
References
Fungicides
Pyrazoles
Anilides
Fluoroarenes | Penflufen | [
"Chemistry",
"Biology"
] | 114 | [
"Fungicides",
"Biocides",
"Functional groups",
"Organic compounds",
"Amides",
"Organic compound stubs",
"Organic chemistry stubs"
] |
78,145,733 | https://en.wikipedia.org/wiki/Robert%20Seiwald | Robert J. Seiwald (born March 26, 1925) is an American retired chemist. He was born in Fort Morgan, Morgan County, Colorado. An only child, his parents were farmers. His father died in 1934 of pneumonia, while his mother died of breast cancer in 1935. Prior to enlisting in the United States Army during World War II in 1944, he enrolled at the University of San Francisco, where he majored in chemistry. During the war, he was a rifleman in the 89th Infantry Division and went to Europe on a ship. In 1954, he studied for his Ph.D. at St. Louis University.
In 1960, Seiwald and Joseph H. Burckhalter received a patent while working at University of Kansas, for their work on fluorescein fluorescein isothiocyanate and rhodamine isothiocyanate, the former being an antibody labeling agent which helps accurately diagnosing various diseases. In 1957, he returned to the University of San Francisco as an organic chemistry professor, a position he held until his retirement in 1999. In 1995, Seiwald and Burckhalter were inducted into the National Inventors Hall of Fame.
Personal life
Seiwald married Joan Walter in 1956. They were married until her death in on May 11, 2023, at the age of 91. The couple had five children in total.
References
1925 births
Living people
University of San Francisco faculty
University of San Francisco alumni
Saint Louis University alumni
20th-century American inventors
United States Army personnel of World War II
American organic chemists | Robert Seiwald | [
"Chemistry"
] | 325 | [
"Organic chemists",
"American organic chemists"
] |
78,145,900 | https://en.wikipedia.org/wiki/Extended%20continental%20shelf | The extended continental shelf, scientific continental shelf, or outer continental shelf, refers to a type of maritime area, established as a geo-legal paradigm by the United Nations Convention on the Law of the Sea (UNCLOS). Through the process known as the extension of the outer limit of the continental shelf or establishment of the outer edge of the continental margin, every coastal state has the privilege, granted by the international community of nations, to acquire exclusive and perpetual rights to exploit the biotic and abiotic resources found on the seabed and subsoil of these maritime areas. These areas are located beyond the 200 nautical miles that make up the state's exclusive economic zone (EEZ) and would otherwise be considered international waters.
In these deep-water areas, resource exploitation was either technically impossible with available methods or economically unfeasible. Thanks to sustained scientific and industrial progress, these oceanic waters have become increasingly accessible through new technologies, which gives these areas extraordinary geopolitical and geoeconomic importance.
Differences with other concepts of continental shelves
In the case of the scientific or extended continental shelf, the coastal state to which it has been granted is the only one entitled to exploit the natural resources found in the seabed and subsoil, whether mineral resources or other non-living resources, as well as living organisms. This includes those organisms that penetrate the seabed or have sedentary habits, defined as those that remain immobile on the seabed during exploitation or move in permanent physical contact with it.
This type of maritime space differs significantly from the geomorphological concept of a continental shelf, which is similar to an epicontinental sea. This concept identifies the submerged extensions of the landmass of the coastal state up to depths of 200 meters.
It also differs from the concept of the legal continental shelf, which refers to the right of states to exploit their maritime projections up to the limit of 200 nautical miles (regardless of the characteristics of the seabed or its depths, and whether or not there is an extension of the coast under the sea) measured from their baselines (exclusive economic zone or EEZ). In this concept, the rights to exploit the seabed and subsoil are combined with rights over the water column and surface.
Scientific or extended shelves are always located in maritime areas more than 200 nautical miles (370.4 km) from the straight baselines from which the width of the territorial sea is measured, and they do not extend beyond 350 nautical miles at the maximum.
History and characteristics
The creation and implementation of this legal concept, which allows coastal states to enjoy exclusive rights over vast oceanic territories, stems from the United Nations Convention on the Law of the Sea (UNCLOS), specifically in Part VI. This multilateral treaty was approved in April 1982 and came into force on November 16, 1994, a year after its ratification by Guyana, which fulfilled the requirement that at least 60 signatory states ratify it.
The regulations developed and issued by UNCLOS have global application. The meeting of the states that are part of the convention established the Commission on the Limits of the Continental Shelf (CLCS), and the validation of the commission gives political and legal legitimacy. This commission is based at the United Nations headquarters in New York.
For a coastal state to acquire rights over scientific continental shelves, it must rigorously follow specific steps. First, it must submit a detailed report to the CLCS, in which the state must demonstrate its rights over a specific area, outlined in a cartographic presentation. This process must consider the scientific-technical guidelines established by UNCLOS, and the report must be based on extensive data collection, including surveys and various scientific analyses, such as gravimetric, bathymetric, magnetometric, geological, geophysical, morphological, seismic, sedimentological studies, etc. Specialists in multiple disciplines, including oceanography, hydrography, geography, cartography, law, and international law, participate in this effort.
The CLCS, through a subcommission of seven members from a total of 21 technical experts in hydrography, geophysics, and geology, reviews the claim. They carefully examine the state's arguments, the technical data, and the accompanying maps. The commission can request clarifying meetings, make recommendations for modifications, or provide scientific-technical advice, potentially reprocessing the submitted data. After completing the analysis, the subcommission issues draft recommendations, which are then approved by the full commission. If the state follows these recommendations, the new limits are validated. If the commission finds excessive extensions, it may recommend adjustments, leaving disputed sections in suspense. The state may accept or revise its claim, and after further review, the commission may finally validate the submission.
Under UNCLOS Article 76.8, once the CLCS validates a state's outer limit, it is definitive and binding, enforceable against third-party states, and internationally mandatory.
Legally, the boundary is drawn by the state itself, with the CLCS only providing recommendations to ensure compliance with UNCLOS requirements. This ensures that the extension aligns with the rights developed under the convention.
The coastal state will submit to the secretary-general of the United Nations cartography, geodetic data, and additional information describing the new outer limit, permanently established, who upon receiving them will give them appropriate dissemination so that such limits are respected by the community of nations.
Formulas for measuring the outer edge of the continental margin
UNCLOS, in Article 76, established complex scientific-technical guidelines that all coastal states must follow when estimating the extent of their continental shelf. These guidelines are synthesized into a combination of 4 rules—2 formulas and 2 restrictions. These standards were debated and agreed upon over several years, finally being approved in New York City on May 13, 1999, during the fifth session.
The procedure for states wishing to expand their maritime area begins with locating the foot of the continental slope, defined as the point of greatest change in gradient at its base. Once this point is identified, formula lines are drawn to find the farthest outer envelope, which will correspond to the outer edge of the continental shelf that the state intends to defend. Each state will choose the formula to use in each section, applying the most convenient based on seabed features and distances, to achieve the greatest possible extension of exclusive continental shelf.
Each formula was proposed by a geologist, and its technical name bears the scientist's last name:
Gardiner formula or sediment thickness formula
Its application results in a line drawn through fixed points where the sedimentary rock thickness is at least 1% of the shortest distance between that point and the foot of the slope.
Hedberg formula or distance formula
When applied, a line is drawn through fixed points located no more than 60 nautical miles from the foot of the continental slope.
Subsequently, the proposal obtained is evaluated through the belonging test, in which it must be demonstrated that the continental shelf extends beyond 200 nautical miles measured from the baselines.
In the next step, restriction rules are applied, which are two:
No point of the claimed area can exceed 350 nautical miles measured from the baselines;
No point of the claimed area can exceed a distance of 100 nautical miles measured from the line where the 2500-meter isobath is located.
By combining the selected formula in the segment with the restrictions applied, the outer limits of the extended continental shelf are traced, with all segments ultimately joining in a continuous line.
Deadlines for submissions
It was established that May 2009 would be the deadline for each state party to UNCLOS to submit a report to the CLCS, arguing their claim for expansion, which could be complete or only for a section. States that submitted on time were allowed to include new supplementary information on other claimed areas in later submissions. A state that did not submit its report by the deadline was disqualified from doing so. In the case of a state that has not yet ratified UNCLOS, any self-initiated maritime boundary expansion has no legal value. It will only acquire rights if it first adheres to the convention, after which it must submit its studies to the CLCS. A 10-year period is granted for this, starting from the date of ratification; if the state fails to submit within this decade, it will lose its right to expansion permanently.
Disputed maritime territories
The procedures established by UNCLOS are based on the principle that "land dominates the sea," meaning the status of maritime spaces legitimated by its bodies derives from the status of the coastal landmasses. If the CLCS encounters overlapping jurisdiction claims or pending conflicts during the extension process—i.e., ocean areas claimed by two or more countries, including those projected from disputed islands—any submission concerning those areas will not be examined or evaluated, as the commission cannot intervene on the substantive issue. Instead, the tracing or definitive allocation will be postponed, subject to the outcome of other legal bodies or negotiation mechanisms appropriate to the nature of these disputes, such as treaties, settlements, negotiations between the parties, mediation, rulings from international courts, etc. Only if the claimants submit a joint presentation to the CLCS—a suggestion that has even been encouraged by the commission itself—or express their consent, will the delimitation not prejudice the final legal settlement.
In July 2023, the International Court of Justice ruled on the priority of a Continental Shelf over an Extended Continental Shelf in the case of the territorial and maritime dispute between Colombia and Nicaragua. Under the terms of the United Nations Convention on the Law of the Sea Article 59 disputed and overlapping claims have no legal force until the dispute is resolved between the opposing parties.
CONVEMAR is an advisory commission that makes recommendations which are not legally binding, and the commission has no jurisdiction over sovereignty issues.
See also
Disputed Territories
International Tribunal for the Law of the Sea
Continental margin
Convention on the Continental Shelf
Territorial waters
Territorial claims in the Arctic#Russia
Dispute over the extended continental shelf in the Southern Zone Sea between Argentina and Chile
Continental shelf of the United States
Continental shelf of Chile
Continental shelf of Russia
References
External links
United Nations – Commission on the Limits of the Continental Shelf
Law of the sea
Oceanography
Continental shelves | Extended continental shelf | [
"Physics",
"Environmental_science"
] | 2,055 | [
"Oceanography",
"Hydrology",
"Applied and interdisciplinary physics"
] |
78,145,977 | https://en.wikipedia.org/wiki/Affordable%20affluence | Affordable affluence refers to a cultural phenomenon where consumers use accessible luxury goods and lifestyles to project status and align themselves with a higher social class, without requiring substantial wealth. This concept is embodied by brands such as Aritzia and Erewhon Market, which position themselves as offering high-end, trendy, or health-conscious products that are relatively accessible to the average consumer.
A related concept is quiet luxury, where the ultra-wealthy signal wealth through subtle means. Quiet luxury emphasizes the widening gap between the ultra-wealthy and the general public, whereas accessible affluence provides a way for the general public to indulge in the lifestyle of the ultra-wealthy.
Origin of the term
The phrase was first used in this context in a 2023 article in The Cut called "Meet the People Working 3 Jobs to Afford Erewhon." One of the interviewees used Erewhon as an archetype of affordable affluence. It was described as “a way for regular people to position themselves adjacent to the upper class.”
Background and description
The phenomenon arises due to an individual's desire to showcase status. For years, companies have strategized how to target the average consumers by providing a product that signals an elevated social status. For instance, Aritzia partnered with celebrities and micro-influencers to make it an aspirational brand at an affordable cost. Erewhon similarly has allowed middle class consumers to subtly signal a higher degree of perceived wealth by purchasing higher priced, but still attainable items. It has allowed middle-class individuals to feel as though they are part of an exclusive culture.
This phenomenon has been seen particularly with Gen Z and Millennials in the setting of financial hardships in the 2020s. Affordable affluence is an example of the lipstick effect. Because traditional status symbols such as expensive cars became relatively more unattainable, posting clips on social media that showcase affordable affluence become an alternative status symbol. Particularly with food, the perception has evolved from a necessity to a luxury. A McKinsey & Company report demonstrated that these generations place a higher importance on groceries than restaurants, travel, and beauty/fashion.
See also
Luxury goods
Quiet luxury
References
Wealth
Social media | Affordable affluence | [
"Technology"
] | 458 | [
"Computing and society",
"Social media"
] |
78,146,206 | https://en.wikipedia.org/wiki/1ES%201741%2B196 | 1ES 1741+196 is a BL Lacertae object (BL Lac) located in the constellation of Hercules. It is located 1.2 billion light years from Earth. It was first discovered in 1996 via an Einstein Observatory X-ray satellite. Because the galaxy's synchrotron peak is found above 1 keV, it is categorized as a high-frequency peaked object.
Characteristics
The nucleus of 1ES 1741+196 is active. It has been classified as an extreme blazar due to having a flat high energy gamma ray spectrum or alternatively, a high-energy BL Lac. One accepted theory for this energy source in most active galactic nuclei is a presence of an accretion disk around its supermassive black hole. The mass of the black hole in the center of the galaxy is estimated to be 8.93 ± 0.70 Mʘ based on a fundamental plane measurement.
Apart from that, 1ES 1741+196 has an isotopic luminosity of ~ 8.2 x 1043 erg s−1, making it less luminous amongst other TeV blazars. When observed in very high energy (VHE) band, 1ES 1741+196 shows no evidence of strong flares. Its X-ray spectrum is known to be variable compared to its steady gamma ray spectrum, with it rising up by a factor of 3 in terms of variability.
The host galaxy of 1ES 1741+196 is an elliptical galaxy, one of the largest and brightest BL Lac host galaxies observed. It has a redshift magnitude relation of -24.85 and a galaxy effective radius of 51.2 kiloparsecs, which its overall luminosity distribution is obtained via a de Vaucouleurs profile. Additionally, there are two galaxy companions within the galaxy's position. They have same redshifts, with projected distances of 7.2 and 25.2 kiloparsecs. Given 1ES 1741+196 has a flat luminosity profile, its position along an impact parameter towards the neighbors and a high ellipticity, this suggests tidal forces. Further evidence also shows a presence of a tidal tail between the companions, indicating the three galaxies are interacting.
1ES 1741+196 has an extended radio jet towards the east direction with a projected position angle of °80. The jet is known to be straight despite showing signs of a 5° bend towards south by 15-20 parsecs from its core. Furthermore, the jet is known to be aligned well with a parsec-scale jet.
References
External links
1ES 1741+196 on SIMBAD
BL Lacertae objects
Hercules (constellation)
1597986
Blazars
Active galaxies
Astronomical objects discovered in 1996 | 1ES 1741+196 | [
"Astronomy"
] | 559 | [
"Hercules (constellation)",
"Constellations"
] |
78,147,448 | https://en.wikipedia.org/wiki/W.%20David%20Kingery%20Award | The W. David Kingery Award is an award presented annually by the American Ceramic Society (ACerS) to individuals who have made significant lifelong contributions to the field of ceramic science and engineering. The award is named in honor of W. David Kingery, a prominent figure in ceramics research, and is one of the highest honors bestowed in the ceramics community, celebrating sustained excellence in research, leadership, and education over the course of a career.
Background
The W. David Kingery Award was established in 1998 by ACerS to honor the memory and contributions of W. David Kingery, whose work transformed the field of ceramics. Kingery is often referred to as the "father of modern ceramics" due to his research in ceramic processing, especially in sintering, a process critical to the formation of dense ceramic bodies from powders. His interdisciplinary approach, which combined elements of materials science, chemistry, and physics, revolutionized the manufacturing and application of ceramic materials.
Kingery's research extended beyond basic science to include practical applications, from high-performance materials used in aerospace and electronics to advanced ceramic technologies in energy production and medicine. His influence as an educator was equally impactful, having authored several foundational textbooks in ceramics and materials science, including the influential Introduction to Ceramics. Throughout his career, Kingery was a prominent advocate for the advancement of ceramic engineering and education, mentoring many future leaders in the field.
Criteria
The award is conferred based on a rigorous evaluation of the nominee's career achievements. It recognizes individuals who have demonstrated sustained excellence and made significant, long-term contributions to the field of ceramics, which may include, but are not limited to:
Breakthroughs in ceramic processing and manufacturing.
Advances in understanding the mechanical, thermal, or electrical properties of ceramic materials.
Contributions to the development of novel ceramic materials for structural, electronic, biomedical, or other applications.
Leadership roles that have advanced the ceramics community, such as through educational programs, mentoring, or service to professional societies.
While the award is open to candidates from both academic and industrial sectors, recipients typically have a body of work that spans decades, influencing not only their own area of expertise but also the broader ceramics community. The award reflects both individual accomplishment and contributions that benefit society as a whole through the advancement of ceramic technology.
Notable Recipients
Many recipients of the W. David Kingery Award have been recognized for their pioneering research and contributions to ceramics, both in academic and industrial settings. These individuals have made advancements in areas such as ceramic processing, high-temperature materials, sintering technologies, and the development of ceramic materials for structural, electronic, and biomedical applications.
References
Ceramic engineering | W. David Kingery Award | [
"Engineering"
] | 530 | [
"Ceramic engineering"
] |
78,147,715 | https://en.wikipedia.org/wiki/PKS%201830-211 | PKS 1830-211 is a gravitationally-lensed blazar in the southern constellation of Sagittarius, one of the most powerful such objects known. It has a high redshift (z) of 2.507, an indicator of its significant distance. This flat-spectrum radio quasar (FSRQ) is one of the brightest extraterrestrial radio sources. In visible light, identification of this object is hampered by the galactic plane and an M-type star that lies near the line of sight.
This quasar was first detected in 1969 during a radio survey by the Parkes Observatory in Australia. In 1984, it was found to display interplanetary scintillation, suggesting structure on angular scales of less than an arc second. Radio observations in 1988 found an unusual double structure separated by an angle of ~1 arc second. The flat radio spectrum and double structure of this feature are suggestive of gravitational lensing by a foreground galaxy. Interferometric radio telescope observation was used to detect an unusually bright Einstein ring in 1991, spanning a radius of .
Radio observations of PKS 1830-211 made over a 13-month period were used to measure changes in flux density. Both components displayed dramatic changes in their flux level, with the fluctuation on one component matched by the other about 44 days later. This lent strong support to the idea this is a gravitationally lensed system. The time delay was refined to 26 days in 1998. In 1996, absorption of neutral hydrogen was detected at a redshift of 0.19, suggesting a possible second lensing galaxy for a compound gravitational lens. This object was confirmed via infrared imagery in 2005. However, this second galaxy is thought to have a negligible effect on the overall lensing.
Imaging of the quasar with the Hubble Space Telescope in 2002 identified the lens galaxy as a normal spiral galaxy at a redshift of 0.886. It is inclined at an angle of 25° to the plane of the sky, appearing nearly face-on. Based on the size of the Einstein ring, this galaxy has a mass of about , which is comparable to the Milky Way. An independent analysis of the same imaging data suggested the possible presence of a main-sequence star within of the target. A third point-like lensed image of the quasar was detected in 2020, located part way between the other two. PKS 1830-211 is a source for gamma-ray emission that undergoes significant flaring.
PKS 1830-211 has been used as a radio source for measuring redshifted molecular species, including ArH+, CF+, HCN, HCO+, H2O, NH3, and OH+. As of 2014, it is the "extragalactic object with the largest number of detected molecular species". In 2023, Rydberg atoms were detected in the foreground galaxy by the MeerKAT telescope array.
References
Further reading
Quasars
Sagittarius (constellation) | PKS 1830-211 | [
"Astronomy"
] | 617 | [
"Sagittarius (constellation)",
"Constellations"
] |
78,147,827 | https://en.wikipedia.org/wiki/Electrostatic%20solitary%20wave | In space physics, an electrostatic solitary wave (ESW) is a type of electromagnetic soliton occurring during short time scales (when compared to the general time scales of variations in the average electric field) in plasma. When a rapid change occurs in the electric field in a direction parallel to the orientation of the magnetic field, and this perturbation is caused by a unipolar or dipolar electric potential, it is classified as an ESW.
Since the creation of ESWs is largely associated with turbulent fluid interactions, some experiments use them to compare how chaotic a measured plasma's mixing is. As such, many studies which involve ESWs are centered around turbulence, chaos, instabilities, and magnetic reconnection.
History
The discovery of solitary waves in general is attributed to John Scott Russell in 1834, with their first mathematical conceptualization being finalized in 1871 by Joseph Boussinesq (and later refined and popularized by Lord Rayleigh in 1876). However, these observations and solutions were for oscillations of a physical medium (usually water), and not describing the behavior of non-particle waves (including electromagnetic waves). For solitary waves outside of media, which ESWs are classified as, the first major framework was likely developed by Louis de Broglie in 1927, though his work on the subject was temporarily abandoned and was not completed until the 1950s.
Electrostatic structures were first observed near Earth's polar cusp by Donald Gurnett and Louis A. Frank using data from the Hawkeye 1 satellite in 1978. However, it is Michael Temerin, William Lotko, Forrest Mozer, and Keith Cerny who are credited with the first observation of electrostatic solitary waves in Earth's magnetosphere in 1982. Since then, a wide variety of magnetospheric satellites have observed and documented ESWs, allowing for analysis of them and the surrounding plasma conditions.
Detection
Electrostatic solitary waves, by their nature, are a phenomenon occurring in the electric field of a plasma. As such, ESWs are technically detectable by any instrument that can measure changes to the electric field during a sufficiently short time window. However, since a given plasma's electric field can vary widely depending on the properties of the plasma and since ESWs occur in short time windows, detection of ESWs can require additional screening of the data in addition to the measurement of the electric field itself. One solution to this obstacle for detecting ESWs, implemented by NASA's Magnetospheric Multiscale Mission (MMS), is to use a digital signal processor to analyze the electric field data and isolate short-duration spikes as a candidate for an ESW. Though the following detection algorithm is specific to MMS, other ESW-detecting algorithms function on similar principles.
To detect an ESW, the data from a device measuring the electric field is sent to the digital signal processor. This data is analyzed across a short time window (in the case of MMS, 1 millisecond), taking both the average electric field magnitude and the largest electric field magnitude during that time window. If the peak field strength exceeds some multiple of the average field strength (4 times the field strength in MMS), then the time window is considered to contain an ESW. After this occurs, the ESW can be associated with the peak electric field strength and categorized accordingly. These algorithms vary in success at detection, since both the time window and detection multiplier are chosen by scientists based on the parameters they wish to detect. As such, these algorithms often have false positives and false negatives.
Interactions
One of the primary physical consequences of ESWs is their creation of electron phase-space holes, a type of structure which prevents low velocity electrons from remaining close to the source of the ESW. These phase-space holes, like the ESWs themselves, can travel stably through the surrounding plasma. Since most plasmas are overall electrically neutral, these phase-space holes often end up behaving as a positive pseudoparticle.
In general, in order to form an electron phase-space hole, the electric potential energy associated with the ESW's potential needs to exceed the kinetic energy of electrons in the plasma (behavior analogous to potential hills). Research has shown that one possible set of situations where this occurs naturally are kinetic instabilities. One observed example of this is the increased occurrence of these holes near Earth's bow shock and magnetopause, where the incoming solar wind collides with Earth's magnetosphere to produce large amounts of turbulence in the plasma.
Forms
The definition of an ESW is broad enough that, on occasion, research distinguishes between different types:
Ion-acoustic solitary waves: A type of ESW that occurs when the electric potential that causes the ESW produces an ion acoustic wave.
Electron-acoustic solitary waves: A type of ESW that produces an acoustic wave associated with electrons. These tend to be substantially faster and higher frequency than ion-acoustic solitary waves.
Supersolitary waves: A type of ESW whose electric potential include pulses on even smaller time scales than the ESW itself.
See also
Soliton
Interplanetary magnetic field
Solar wind
Electric potential
Turbulence
Time domain electromagnetics
Notes
a.An ESW itself is strictly an electromagnetic phenomenon, and as such is technically non-dependent on media. However, this technicality should be observed with caution. Nearly all conditions that give rise to an ESW are theorized to be dependent on the plasma medium they reside in.
b.Though the identity of the other 3 co-authors is known for certain, the career of K. Cerny after the publishing of their paper is poorly documented. The first name, date, school, and major associated with graduation heavily suggest that Keith Cerny is the K. Cerny credited on the paper, but this is (as-of-yet) unconfirmed.
References
Physics
Wave mechanics
Space physics
Solitons
1982 in science
Waves in plasmas
Quasiparticles | Electrostatic solitary wave | [
"Physics",
"Materials_science",
"Astronomy"
] | 1,224 | [
"Waves in plasmas",
"Physical phenomena",
"Matter",
"Outer space",
"Plasma phenomena",
"Classical mechanics",
"Waves",
"Wave mechanics",
"Condensed matter physics",
"Quasiparticles",
"Subatomic particles",
"Space physics"
] |
78,148,111 | https://en.wikipedia.org/wiki/Model%20compression | Model compression is a machine learning technique for reducing the size of trained models. Large models can achieve high accuracy, but often at the cost of significant resource requirements. Compression techniques aim to compress models without significant performance reduction. Smaller models require less storage space, and consume less memory and compute during inference.
Compressed models enable deployment on resource-constrained devices such as smartphones, embedded systems, edge computing devices, and consumer electronics computers. Efficient inference is also valuable for large corporations that serve large model inference over an API, allowing them to reduce computational costs and improve response times for users.
Model compression is not to be confused with knowledge distillation, in which a separate, smaller "student" model is trained to imitate the input-output behavior of a larger "teacher" model.
Techniques
Several techniques are employed for model compression.
Pruning
Pruning sparsifies a large model by setting some parameters to exactly zero. This effectively reduces the number of parameters. This allows the use of sparse matrix operations, which are faster than dense matrix operations.
Pruning criteria can be based on magnitudes of parameters, the statistical pattern of neural activations, Hessian values, etc.
Quantization
Quantization reduces the numerical precision of weights and activations. For example, instead of storing weights as 32-bit floating-point numbers, they can be represented using 8-bit integers. Low-precision parameters take up less space, and takes less compute to perform arithmetics with.
It is also possible to quantize some parameters more aggressively than others, so for example, a less important parameter can have 8-bit precision while another, more important parameter, can have 16-bit precision. Inference with such models requires mixed-precision arithmetics.
Quantized models can also be used during training (rather than after training). PyTorch implements automatic mixed-precision (AMP), which performs autocasting, gradient scaling, and loss scaling.
Low-rank factorization
Weight matrices can be approximated by low-rank matrices. Let be a weight matrix of shape . A low-rank approximation is , where and are matrices of shapes . When is small, this both reduces the number of parameters needed to represent approximately, and accelerates matrix multiplication by .
Low-rank approximations can be found by singular value decomposition (SVD). The choice of rank for each weight matrix is a hyperparameter, and jointly optimized as a mixed discrete-continuous optimization problem.
Training
Model compression may be decoupled from training, that is, a model is first trained without regard for how it might be compressed, then it is compressed. However, it may also be combined with training.
The "train big, then compress" method trains a large model for a small number of training steps (less than it would be if it were trained to convergence), then heavily compress the model. It is found that at the same compute budget, this method results in a better model than lightly compressed, small models.
In Deep Compression, the compression has three steps.
First loop (pruning): prune all weights lower than a threshold, then finetune the network, then prune again, etc.
Second loop (quantization): cluster weights, then enforce weight sharing among all weights in each cluster, then finetune the network, then cluster again, etc.
Third step: Use Huffman coding to losslessly compress the model.
The SqueezeNet paper reported that Deep Compression achieved a compression ratio of 35 on AlexNet, and a ratio of ~10 on SqueezeNets.
References
Review papers
Machine learning
Deep learning | Model compression | [
"Engineering"
] | 739 | [
"Artificial intelligence engineering",
"Machine learning"
] |
78,148,249 | https://en.wikipedia.org/wiki/Word%20equation | A word equation is a formal equality between a pair of words and , each over an alphabet comprising both constants (c.f. ) and unknowns (c.f. ). An assignment of constant words to the unknowns of is said to solve if it maps both sides of to identical words. In other words, the solutions of are those morphisms whose restriction to is the identity map, and which satisfy . Word equations are a central object in combinatorics on words; they play an analogous role in this area as do Diophantine equations in number theory. One stark difference is that Diophantine equations have an undecidable solubility problem, whereas the analogous problem for word equations is decidable.
A classical example of a word equation is the commutation equation , in which is an unknown and is a constant word. It is well-known that the solutions of the commutation equation are exactly those morphisms mapping to some power of . Another example is the conjugacy equation , in which and are all unknowns. The solutions of this equation are precisely those morphisms sending and to conjugate words, with the image being filled in as appropriate.
Many subclasses of word equations have been introduced, some of which include:
constant-free equations, which are those such that comprise unknowns only. Such equations have a trivial solution wherein all their unknowns are erased; as such, they are usually studied over free semigroups.
quadratic equations, which are those containing each of their unknowns at most twice. This is exactly the class of word equations on which the Nielsen Transformations algorithm (c.f. below) terminates.
word equations in one unknown, which can be checked for their solubility in linear time.
History
The study of word equations was initiated by Willard Quine as early as 1946. Quine proved that the first-order theory of word equations is essentially equivalent to the first-order theory of arithmetic. In 1954, Andrey Markov coined the term "word equation", and introduced the solubility problem for them: decide whether a given word equation admits a solution. For a long time, it was hoped that this problem was undecidable. One reason for this is that it was expected, (incorrectly, it turns out), that word equations might provide an intermediary step between Hilbert's Tenth Problem and the undecidable problems relating to Turing machines.Further contributions were made in the early 1970s with the work of André Lentin and Juri Ilich Hmelevskii. In 1976, Gennady Makanin introduced a method by which it could be determined whether any given word equation admitted a solution. That this procedure, which has come to be known as Makanin's algorithm, exists is very difficult to prove, and it is one of the most celebrated results in combinatorics on words. Makanin's algorithm is considered to be one of the most conceptually difficult existing in literature, and it is also highly intractable, requiring (in its initial formulation) triply exponential time. Thus, there were many attempts to improve upon it. In 1999, Wojciech Plandowski introduced a novel algorithm, showing that the solubility problem for word equations is in PSPACE.
In 2006, Plandowski and Wojciech Rytter showed that minimal solutions of word equations are highly (i.e., exponentially) compressible using Lempel-Ziv encoding. It is conjectured that the length of a minimal solution of a word equation is (at most) singly exponential in the length of . If this conjecture is true, then Plandowski and Rytter's result yields a straightforward "guess-and-verify" NP algorithm for the solubility problem: they show that a solution can be verified whilst working only with its LZ-compressed representation , and the conjecture being true would imply that has size polynomial in . As it stands, the last part of the complexity analysis—the question as to whether solving word equations is NP-complete—remains open. (NP-hardness follows immediately from the fact that solving word equations generalises the NP-complete problem of pattern matching).
Methods of solution
There is no "elementary" algorithm for determining whether a given word equation admits a solution. The algorithms mentioned above are all of theoretical interest, but they'll not help in solving a word equation by hand, for instance. There exist however a few methods that can sometimes help with this:
Length arguments
Because a solution to a word equation must unify its two sides, one can use the multiset of symbols occurring on either side of to deduce a linear equality in the lengths of the images of the unknowns. For instance, the form of implies that its solutions must satisfy , which narrows down the set of possible to check. Similar arguments can allow for a word equation to be "split up" into smaller ones if it can be deduced positions within the two sides of which must line up in all solutions of . For instance, the midpoints of each side of can be detected via a length argument, and hence that word equation can be split into the system .
Appeal to periodicity
Another useful tool for reasoning about word equations is the Periodicity Lemma of Fine and Wilf, which describes what happens if a certain word has multiple periods (i.e., distances at which its letters repeat). Consider, for instance, the word equation . Suppose that is one of its solutions. Then . By taking a suitable conjugacy in this identity, one can infer that there exists some conjugate of which is such that . Now a length argument permits for the midpoint of each side to be identified here, and it follows from this observation that . Herein is the commutation equation, whence and are powers of a common word. Now the infinite words and have a common prefix of length . Since , the Periodicity Lemma can be applied. Its conclusion here is that and are powers of a common word too. Thus, every solution of maps and to powers of a common word.
Nielsen transformations
Let be a word equation, such that , and . Here shall be presented a conceptually simple method (called Nielsen transformations algorithm, or Levi's Method.) to determine whether is soluble, with the caveat that the method terminates only on quadratic word equations (as defined above).
The idea of the algorithm is to "guess" how the lengths of and compare in some solution of . Either , , or . In the first case, one can apply the string-rewriting rule to , where (after the rewriting) is a new quantity whose meaning is "what's left of the old once is removed". Symmetrically, in the second case, one can apply the rule , and in the third case . The present method actually makes all three guesses; for each of them (separately) it rewrites to account for the guess having been made.
By construction, there will be some cancellation at the start of after applying each string-rewriting rule. (For instance, applying to the equation yields , which cancels down to ). The method always takes advantage of this cancellation; the hope is that it is enough to counteract the string-rewriting rule, which (in general) will have made the equation longer.
The algorithm thus amounts to exhaustively applying these transformations. It is natural to view the workings of the algorithm as the construction of a graph , whose nodes are the reached equations, and edges are the transformations between them. If the trivial word equation , (where is the empty word) is ever encountered during this construction, then is surely solvable. Conversely, if is soluble, then must appear in . So, by this method (assuming is finite) it can be determined whether admits a solution.
Systems of word equations
One can define systems of word equations in the natural way. A solution of such a system is a morphism that solves simultaneously every equation in . A natural extension is to consider Boolean formulas of word equations, in which also negation and disjunction is allowed. In fact, every system (and even every Boolean formula) of word equations, is equivalent to a single word equation. Thus, many results on word equations generalise immediately to such systems (resp. formulas). It must be said, however, that the transformation into a single word equation can introduce extra unknowns, and this is sometimes by necessity.
Two word equations (or systems thereof) are called equivalent if they have the same set of solutions. A system of word equations is called independent if it is not equivalent to any of its proper subsystems. Put another way, an independent system of word equations is one such that every can be solved "independently", i.e., without solving any of the other . An interesting compactness theorem, usually bearing the name of Andrzej Ehrenfeucht, states that an infinite system of word equations, and with a finite number of unknowns, is necessarily equivalent to one of its finite subsystems. It follows that any independent system of word equations with a finite number of unknowns is itself finite.
Expressing formal languages and relations
Word equations can be used to characterise properties of (tuples of) words. For instance, a word ends in if and only if it is the image in some solution of the word equation . Similarly, two words commute if and only if they are the images in some solution of the word equation . In this sense, word equations can be thought of as mechanisms for expressing formal languages, in analogy with automata and formal grammars. It is not known exactly which properties of (tuples of) words are expressible in via word equations in this way. In particular, to show that a relation is inexpressible by word equations is often quite challenging. (An example of an inexpressible property is " is primitive").
It should be also noted that even characterising the solution set of a single word equation is complicated. Hmelevskii proved that, although the solutions to three-unknown constant-free equations can be given in terms of finite expressions with word and integer parameters, this is not true (in general) for four-unknown constant-free equations. In fact, is an example of such a "non-parametrisable" word equation.
Extended theories and connections to string solving
One can augment word equations with other types of constraints on the values , . For instance, in 1968, Yuri Matiyasevich considered an extension of word equations by "length constraints" as a possible tool for showing the unsolvability of Hilbert's tenth problem. These length constraints amounted to linear inequalities in the unknowns , . Sometimes, allowing extra constraints (alongside word equations) leads to theories with undecidable solubility problems, but it is also possible to add less powerful constraints and end up with a theory that's still decidable. An example of the former type of constraint is requiring that some should be Abelian equivalent (i.e., anagrams of one another); an example of the latter type is requiring that some should belong to a given regular language . For Matiyasevich's extension with the length constraints, the solubility problem still has open decidability status.
There has been recent interest in the theory of word equations (and more general theories based on it), from the practical point of view of those developing software verification tools called string solvers. These tools, which are increasingly popular, seek to solve algorithmically constraint satisfaction problems about strings. Such problems take the form of a set of constraints, which an unknown set of strings must satisfy. The string solver should then determine whether strings exist which satisfy all the given constraints. A typical goal of such a tool would be to guarantee that a particular piece of software was free from some string-related vulnerability, such as cross-site scripting or code injection.
The building blocks of the constraints used in these tools are the standard questions one might ask of strings, such as "is a substring of ?", "what is the length of string ?", and "what is the index of string in string ?". Ostensibly, these constraints can be modelled by theories based on word equations, and as such, string solver tools must be capable of dealing with these theories algorithmically, (at least in the subcase of those equations and formulas that actually arise in practice).
Relation to the defect effect
The defect theorem is a central result to combinatorics on words. It says that, if a set of words satisfies a nontrivial relation, then the words of can be (simultaneously) expressed as powers of words, where . Such a set is then said to possess a "defect effect" of order . Systems of word equations, (at least "nontrivial" ones), express the fact that a certain finite set of words, (namely the images of the unknowns ), satisfy some nontrivial relation(s). So it can be said that systems of word equations cause a defect effect in the sets of words coming from solutions of .
The defect effect caused by certain systems of word equations has been studied., and there exist some surprising results to this end showing that the "dimensionality properties" of sets of words are actually quite weak. For instance, it is known that here exists an independent system of equations of size , containing unknowns, which is such that causes only a defect effect of order .
Role within abstract algebra
There has been much research into formulating and solving equations within different structures of abstract algebra (e.g., groups and semigroups). Word equations, as presented here, are simply equations in free monoids. Equations in free semigroups are closely related to these; in fact, they are just word equations with the additional requirement that the solution morphism is nonerasing. One can also consider equations in free groups, although the theory of such objects differs in many ways from the discussion presented here. Another result of Makanin's states that the solubility problem for equations in free groups is again decidable.
References
Combinatorics on words | Word equation | [
"Mathematics"
] | 2,938 | [
"Combinatorics on words",
"Combinatorics"
] |
78,148,688 | https://en.wikipedia.org/wiki/MobileNet | MobileNet is a family of convolutional neural network (CNN) architectures designed for image classification, object detection, and other computer vision tasks. They are designed for small size, low latency, and low power consumption, making them suitable for on-device inference and edge computing on resource-constrained devices like mobile phones and embedded systems. They were originally designed to be run efficiently on mobile devices with TensorFlow Lite.
The need for efficient deep learning models on mobile devices led researchers at Google to develop MobileNet. , the family has four versions, each improving upon the previous one in terms of performance and efficiency.
Features
V1
MobileNetV1 was published in April 2017. Its main architectural innovation was incorporation of depthwise separable convolutions. It was first developed by Laurent Sifre during an internship at Google Brain in 2013 as an architectural variation on AlexNet to improve convergence speed and model size.
The depthwise separable convolution decomposes a single standard convolution into two convolutions: a depthwise convolution that filters each input channel independently and a pointwise convolution ( convolution) that combines the outputs of the depthwise convolution. This factorization significantly reduces computational cost.
The MobileNetV1 has two hyperparameters: a width multiplier that controls the number of channels in each layer. Smaller values of lead to smaller and faster models, but at the cost of reduced accuracy, and a resolution multiplier , which controls the input resolution of the images. Lower resolutions result in faster processing but potentially lower accuracy.
V2
MobileNetV2 was published in March 2019. It uses inverted residual layers and linear bottlenecks.
Inverted residuals modify the traditional residual block structure. Instead of compressing the input channels before the depthwise convolution, they expand them. This expansion is followed by a depthwise convolution and then a projection layer that reduces the number of channels back down. This inverted structure helps to maintain representational capacity by allowing the depthwise convolution to operate on a higher-dimensional feature space, thus preserving more information flow during the convolutional process.
Linear bottlenecks removes the typical ReLU activation function in the projection layers. This was rationalized by arguing that that nonlinear activation loses information in lower-dimensional spaces, which is problematic when the number of channels is already small.
V3
MobileNetV3 was published in 2019. The publication included MobileNetV3-Small, MobileNetV3-Large, and MobileNetEdgeTPU (optimized for Pixel 4). They were found by a form of neural architecture search (NAS) that takes mobile latency into account, to achieve good trade-off between accuracy and latency. It used piecewise-linear approximations of swish and sigmoid activation functions (which they called "h-swish" and "h-sigmoid"), squeeze-and-excitation modules, and the inverted bottlenecks of MobileNetV2.
V4
MobileNetV4 was published in September 2024. The publication included a large number of architectures found by NAS. Compared to the architectural modules used in V3, the V4 series included the "universal inverted bottleneck", which includes both inverted residual and inverted bottleneck as special cases, and attention modules with multi-query attention.
See also
Convolutional neural network
Deep learning
TensorFlow Lite
External links
References
Computer vision
Machine learning
Google software | MobileNet | [
"Engineering"
] | 732 | [
"Artificial intelligence engineering",
"Packaging machinery",
"Machine learning",
"Computer vision"
] |
78,149,459 | https://en.wikipedia.org/wiki/Kamilah%20Taylor | Kamilah Taylor is a Jamaican software engineer; she is known for advocating for women and people of color in the tech industry.
Early life and education
Taylor was born in Jamaica, to parents Ashley Hamilton-Taylor and Delta Taylor. Her parents still reside in Jamaica, where her father is a computer science lecturer at University of the West Indies, and her mother is a teacher at St. Andrew's Prep School.
In Taylor's earlier years, she attended Mona Preparatory School in Kingston, Jamaica until the fifth grade. She completed middle school at Holcomb Bridge and attended North Spring Charter high school in Atlanta. Both of which were magnet schools centered around advanced math and sciences, as well as performing arts. She obtained a bachelor's degree in math and computer science from the University of the West Indies. She also earned a master's degree in computer science with a concentration in robotics from the University of Illinois at Urbana-Champaign.
Career
Taylor's career started at Wolfram Research, Inc directly after completing graduate school. In late 2011, she applied to LinkedIn and joined the company in 2012 as a software engineer. Taylor led the infrastructure and flagship app integrations on the LinkedIn Learning app. In 2017, she was noted as one of Business Insider’s most powerful female engineers in the United States for her work with LinkedIn. Taylor was involved via Google chat in the Girls in ICT Caribbean hackathon, which was held in Jamaica, Trinidad, and Barbados — International Girls in ICT Day in 2017.
An engineering manager for Uber tried recruiting Taylor for a developer position at the San Francisco startup. However, she declined the position due to a major sexual harassment controversy with the company. The female manager replied telling her that “sexism is systemic in tech”, which then sparked some backlash via Twitter.
Taylor is a co-author of the book, Women in Tech.
References
Wikipedia Student Program
Living people
Jamaican engineers
Systems engineers
Women systems engineers
Year of birth missing (living people) | Kamilah Taylor | [
"Engineering"
] | 401 | [
"Systems engineers",
"Systems engineering"
] |
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