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66,277,577 | https://en.wikipedia.org/wiki/European%20Processor%20Initiative | (EPI) is a European processor project to design and build a new family of European low-power processors for supercomputers, Big Data, automotive, and offering high performance on traditional high-performance computing (HPC) applications and emerging applications such as on machine learning. It is led by a consortium of European companies and universities.
The project is divided in multiple phases funded under Specific Grant Agreements. The first grant agreement is implemented under the European Commission program Horizon 2020 (FPA: 800928) in the December 2018 to November 2021 time span. The second agreement will be implemented afterwards under the EuroHPC Joint Undertaking which issued a call, which was answered in January 2021 by the same consortium (H2020-JTI-EuroHPC-2020-02 FPA in EPI (phase II)).
The processor that is to be developed is a system on a chip (SoC) that makes use of the RISC technology, implements microprocessor cores of ARM architecture and accelerators, and specialises in matrix calculations and deep learning for artificial intelligence. The processor is designed to be integrated in an exascale supercomputer, but also to be implemented in cars.
Objectives
The aim of the EPI project is to design and build a high-performance, low-power processor, implementing vector instructions and specific accelerators, such as accelerators for AI, with high-bandwidth memory access. The design will be based on the results obtained through an intensive use of simulation, the development of a complete software stack and the use of advanced semiconductor manufacturing technologies. During the development of the processor, a co-design methodology will be implemented to ensure that the processor is suitable for efficiently running many applications and that it is equipped with the appropriate software development tools. The objective of the EPI is to develop European know-how on the design and construction of processors for high-performance computing, allowing Europe technological sovereignty.
Members
EPI is a non-legal entity, a project organized by 30 institutions from 10 countries in Europe. The members of the consortium are:
History
The initiative started in 2015, in the aim to produce an exascale supercomputer by 2023. The first phase of the project started in December 2018. In the summer of 2019, the basis of the architecture was decided. In January 2020, the first prototype was presented.
Organization of the project
The European Processor Initiative has five streams of operation. The first four are technical streams (Common Platform and Global Architecture, HPC General Purpose Processor, Accelerator, Automotive platform), while the last one is dedicated to the coordination and communication activities.
See also
Quintauris, a European joint company that aims standardizing RISC-V
References
Bibliography
Michael Feldman. "European Processor Initiative Readies Prototype". The Next Platform. Boone, NC: January 27, 2020. https://www.nextplatform.com/2020/01/27/european-processor-initiative-readies-prototype/
Michael Feldman. "First European Pre-Exascale Supercomputers Forgo Homegrown CPUs". The Next Platform. Boone, NC: November 20, 2019. https://www.nextplatform.com/2019/11/20/first-european-pre-exascale-supercomputers-forgo-homegrown-cpus/ [talks about the delay in EPI]
Nitin Dahad. "European Processor Initiative Announces Common Platform For HPC." EE Times Europe. Ebersberg, Germany. November 5, 2019. https://www.eetimes.eu/european-processor-initiative-announces-common-platform-for-hpc/
Doug Black. "An Update on the European Processor Initiative". Inside HPC. 26 September 2019. https://insidehpc.com/2019/09/an-update-on-the-european-processor-initiative/
Calista Redmond. "How the European Processor Initiative is Leveraging RISC-V for the Future of Supercomputing". Inside HPC. Westborough, MA. 22 August 2019. https://insidehpc.com/2019/08/how-the-european-processor-initiative-is-leveraging-risc-v-for-the-future-of-supercomputing/
Sebastian Moss. "European Processor Initiative delivers first architectural designs to the European Commission". Data Centre Dynamics. London: June 4, 2019. https://www.datacenterdynamics.com/en/news/six-months-european-processor-initiative-delivers-architectural-designs-european-commission/
Dan Olds. "The Plan for Europe’s Homegrown Exascale HPC". The Next Platform. Boone, NC: October 20, 2018. https://www.nextplatform.com/2018/10/24/the-plan-for-europes-homegrown-exascale-hpc/ [presents EPI initial timeline]
European Commission. "European Processor Initiative: Consortium to Develop Microprocessors for Future Supercomputers". R&D World. 26 March 2018. https://www.rdworldonline.com/european-processor-initiative-consortium-to-develop-microprocessors-for-future-supercomputers/
External links
Official website
ARM architecture
Processor
Horizon 2020 projects
Information technology organizations based in Europe
Microprocessors
Science and technology in Europe
Supercomputers | European Processor Initiative | [
"Technology"
] | 1,152 | [
"Supercomputers",
"Supercomputing"
] |
66,278,380 | https://en.wikipedia.org/wiki/Joseph%20McLain | Joseph Howard McLain (July 11, 1916 – July 26, 1981) was an American chemist. He was a professor at Washington College and became college president. He is best known for his expertise in solid state chemistry and pyrotechnics. He held 30 patents, including for smoke grenades, underwater torches, and flares.
Biography
Joseph McLain was born in Weirton, West Virginia on July 11, 1916, the son of Howard and Elizabeth McLain. He spent his childhood in Baltimore, Maryland. Like his older brother, McLain was educated at Washington College. While in college, McLain was a member of Theta Chi, president of the class of 1937, and played basketball, football, lacrosse, and track. He did his doctoral work at Johns Hopkins University in chemistry. During World War II, McLain paused his education to serve as a major in the US Army Chemical Corps doing research on smoke screens and pyrotechnics.
Joseph McLain received his doctorate in 1946 and joined the faculty of Washington College the same year. While he was a professor, McLain was a partner in the Kent Manufacturing Company, which made fireworks, until there was an explosion at the plant in 1954. During the explosion, McLain rescued two women from the plant. After the disaster, McLain and his partners dissolved the company and McLain and worked on safety standards for fireworks with fellow Washington College alumnus and professor John Conkling. The pair wrote recommendations for the safe storage for fireworks that became part of the first US standards. In addition to his pyrotechnic research, McLain was active in environmental work, serving as a trustee of the Chesapeake Bay Foundation and sitting on Maryland Water Pollution Control Commission. In 1973, McLain became the president of Washington College. He is the only alumnus of the school to ever serve as president. McLain took a leave of absence from the college in 1981 and died in Baltimore at Johns Hopkins Hospital the same year.
Personal life
Joseph McLain was married to Margret Anne Hollingsworth McLain.
Publications
References
1981 deaths
People from Weirton, West Virginia
Military personnel from West Virginia
Johns Hopkins University alumni
Presidents of Washington College
Washington College alumni
Washington College faculty
1916 births
Solid state chemists
20th-century American academics | Joseph McLain | [
"Chemistry"
] | 458 | [
"Solid state chemists"
] |
66,279,348 | https://en.wikipedia.org/wiki/Sourcetrail | Sourcetrail was a FOSS source code explorer that provided interactive dependency graphs and support for multiple programming languages including C, C++, Java and Python.
History
The project was started by Eberhard Gräther after an internship at Google where he worked on Google Chrome, and noticed that he consumed a lot of time (1 month) to implement a simple feature that he expected to be done in 1–2 hours. This was his motivation to develop a tool that helps in understanding the consequences of source code modifications. The project started as a commercial project in 2016 under the name Coati. In November 2019, Sourcetrail was released as open-source software under version three of the GNU General Public License.
The project was discontinued in 2021.
Concept
Most of a programmer's time is invested in reading the source code. Therefore, Sourcetrail is intended to help the developers to understand the source code and the relationship between different components. Sourcetrail builds a dependency graph after indexing the source code files and provides a graphical overview of the source code.
It is built in an extendable way, so it could be extended to support more programming languages.
See also
Software visualization
References
External links
Archived Repository
Visualization software
Static program analysis tools
Software metrics
Infographics
Software maintenance
Software development
Software quality
Source code
Discontinued software | Sourcetrail | [
"Mathematics",
"Technology",
"Engineering"
] | 269 | [
"Metrics",
"Quantity",
"Computer occupations",
"Software metrics",
"Software engineering",
"Software maintenance",
"Software development"
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66,281,182 | https://en.wikipedia.org/wiki/Nicolaus%20Copernicus%20Astronomical%20Center%20of%20the%20Polish%20Academy%20of%20Sciences | The Nicolaus Copernicus Astronomical Center (Polish: Centrum Astronomiczne im. Mikołaja Kopernika), also CAMK or NCAC, is a Polish scientific research institute of the Polish Academy of Sciences headquartered in Warsaw, Poland. It is a leading institution in the country in the field of astronomy.
History
In the 1950s the Polish Academy of Sciences began planning for a new center for astronomers from all over Poland. However, a few years later the Academy's administration decided to withdraw from the project, and it was never funded. In the early 1970s a group of Polish astronomers proposed a new initiative. During an assembly of the Polish Academy of Sciences, professors Bohdan Paczyński and Józef Smak presented a project for a theoretical-astrophysics institute, in order to overcome problems related to the high cost of building a telescope.
In May 1971 the US National Academy of Sciences sent an envoy to Poland from Yerkes Observatory. The envoy spoke with many representatives of the Polish astronomical community, and a more precise concept of CAMK emerged. It was well received by the US National Academy of Sciences; and the US could provide substantial financial support for the CAMK's construction.
There were, in US-owned funds, nearly $351 million Polish zlotys of "wheat money". This amount of Polish zlotych had accumulated as a result of US agricultural sales to Poland following World War II. At that time the Polish currency could not be converted into other currencies, and so could not be counted in the US federal budget. It was therefore convenient for both the United States and for Poland to build CAMK with those funds. Part of the Polish "wheat debt" to the US could be cancelled, at no cost in dollars to the US government.
The CAMK center was built in Siekierki, then a rather poor district of Warsaw. The main road of Siekierki, ulica Bartycka, was also built at that time to connect the institute with the rest of the city. This new building was inaugurated on May 24, 1978. Next year, CAMK was licensed to award PhD degrees. Since then, CAMK maintains its own hotel for visitors and manages funds to support PhD students and provide research fellowships for more senior scientists.
In 1981, the martial law was declared in Poland in order to suppress the Solidarity movement. In this period, many CAMK employees chose permanent emigration. With their presence abroad, they were providing journals for the library, spare parts for the ageing computer system, and money for postdocs and short-term visitors. In fact, during the marital-law, the right to travel abroad was restricted, making research and collaborations difficult. Some CAMK scientists were even jailed for their pro-Solidarity activities.
Bans and restrictions were ultimately lifted in 1989, with the end of the so-called Polish People's Republic: Polish astronomy and CAMK started to grow and gain more international relevance. With the advent of internet in Poland, CAMK was one of the first places in Poland to connect to the world-wide-web: the early parabola used for the internet connection in the early '90s is still visible in the CAMK's front garden from ulica Bartycka.
Description
The main subjects of research include: stellar evolution, binary stars, asteroseismology, circumstellar matter, compact objects (neutron stars, black holes), accretion processes, structure and evolution of active galaxies, cosmology and extrasolar planets. In 2020 CAMK employed 69 researchers.
The CAMK center has also a Department of Astrophysics in Toruń, a Polish city famous for being Nicolaus Copernicus's hometown and its medieval old town.
References
Astronomy institutes and departments
Institutes of the Polish Academy of Sciences
Organizations established in 1976
1976 establishments in Poland
Research institutes established in 1976 | Nicolaus Copernicus Astronomical Center of the Polish Academy of Sciences | [
"Astronomy"
] | 792 | [
"Astronomy organizations",
"Astronomy institutes and departments"
] |
66,281,758 | https://en.wikipedia.org/wiki/Scope%20mount | Scope mounts are rigid implements used to attach (typically) a telescopic sight or other types of optical sights onto a firearm. The mount can be made integral to the scope body (such as the Zeiss rail) or, more commonly, an external fitting that clamp onto the scope tube via screw-tightened rings (similar to pipe shoes). The scope and mount are then fastened onto compatible interfaces on the weapon. Words such as mounts and bases are used somewhat loosely, and can refer to several different parts which are either used together or in place of each other as ways to mount optical sights to firearms.
Attachment interfaces for scope mounts vary according to weapon design and user choice. Traditionally scope mounts are fastened onto firearms via tapped screw holes (usually on the receiver) and/or clamps (onto the barrel or stock). Since the mid-20th century, dovetail rails, where the mount is slided over a straight dovetail bracket with an inverted isosceles trapezoid cross-section and fixed tight in position with clamping screws, became more common due to the ease of installation and removal. Later, the hexagonally cross-sectioned rail interface systems such as Weaver rail became popular and was later modified into the Picatinny rail in the early 1990s, which became the standardized military-use mounting interface for NATO troops in 1995. The Picatinny rail was officially replaced by the metrified NATO Accessory Rail for military use in 2009, although it remained popular in the civilian market for both scope and accessory mounting.
Scope mounts can be either one-piece (a single implement with multiple clamping rings) or multi-piece (usually two or more individual scope rings). These mounts are usually fastened with screws to specified tensions (which warrants the use of torque screwdrivers), but sometimes they are manually tightened via thumbscrews, and may even have Quick Release (QR) designs. As of 2020, the Picatinny rail is arguably the most widespread scope mounting standard for new firearms, although there are many proprietary and brand-specific types of mounts that can either be used with Picatinny rails, or as completely different design alternatives (see the section on Link between scope and firearm). Scope mounts may be offered by firearm and scope manufacturers, or bought as aftermarket accessories.
Integral scope mounts
Zeiss rail
Among scopes for rail mounts, the 22.5-degree V-shaped Zeiss rail is the most prevalent standard. It was introduced in 1990. After the patent expired in 2008, compatible scopes have been offered from manufacturers such as Blaser, Leica, Minox, Meopta, Nikon, Noblex (formerly Docter), Schmidt & Bender and Steiner. It has therefore, in some sense, become the de facto industry standard for scope mounting rails. The system has so far seen most use on the European high end market.
Swarovski SR rail
The Swarovski SR rail (patented in 2002, introduced in 2005 The Swarovski SR rail is also used by Kahles, a Swarovski subsidiary.) has a flat rail with many "teeth" as recoil lugs, and is only offered on scopes from Swarovski and its subsidiary Kahles. It separates itself from the Zeiss rail in that it is not neither stepless nor self-centering.
S&B Convex rail
A former competing standard was the halv-circle shaped Schmidt & Bender Convex rail also introduced in 2005. Schmidt & Bender after a few years changed to the Zeiss rail standard. In contrast to the Zeiss and Swarovski systems, the S&B Convex rail had the possibility to add a cant to the scope when mounting, such that the reticle is not horizontal to the ground.
70-degree prism rail
There is an older European system with an upside-down V-shape (70 degrees). This system has little widespread use today. The advantage of this system was that it at one time was offered by most European scope manufacturers, but the disadvantage was that the rail had to be drilled for a screw each time the eye relief was to be adjusted. All new standards for rail mounts have addressed this issue.
Ring mounts
Ring mounts usually consist of a base attached to the firearm and rings (usually two) attached to the sight. The rings are usually made of steel or aluminum. Common diameters on ring mounts are 25.4 mm (1 inch), 26 mm, 30 mm and 34 mm. There are big differences in the strength and ability of sustained precision on different assemblies. With weak cartridges such as .22 LR applied in light-use scenarios, a pair of skinny aluminium rings may work well, while firearms with very powerful recoil often combined with a heavy sight may require steel rings or thicker aluminum rings with recoil lugs to be used.
Sizes
Scopes for ring mounts are available in many different sizes. The most common ones are:
1 inch (25.4 mm)
30 mm
34 mm
Some less common standards are:
26 mm – Some older European scopes
35 mm – Some IOR, Vortex and Leupold models
36 mm – Some Zeiss and Hensoldt models
40 mm – Some IOR models and Swarovski dS
Lapping
For a ring assembly to grip evenly, it is important that the scope rings are circular and coaxial with the scope tube. On ring mounts that grip unevenly, the ring mount can be lapped to prevent uneven pressure when mounting. One scopes made for ring mounts, it is not uncommon to get ring marks when mounting the rings.
Ring inserts
There are insert rings on the market which allows for mounting a scope inside a ring mount of a larger diameter. An example could be to mount a scope with a 1-inch (25.4 mm) tube in a 30 mm mount using a plastic insert.
There are also special ring mounts in the market with circularly shaped ring inserts made to provide stress free mounting without lapping, with Burris Signature Rings and Sako Optilock Rings as two well-known examples. Burris Signature was introduced in 1995. A patent was applied for in 1994, and was granted in 1995. Sako Optilock has been sold since some time in the early 2000s. The trade name Optilock was registered in the US in December 1997, and has been marketed in the US since December 2001. In 2000, Sako was sold to Beretta Holding. In 2002, Burris was also sold to Beretta Holding, and thus Burris and Sako got the same owners. Burris' original patent for the rings with the circular insertes was considered to have expired in 2014, and as of 2020 is listed as "definitely expired".
In 2015, XTR Signature Rings was launched as a further development of the Burris Signature series. The XTR variant differs in that it has two circular cavities per ring assembly versus one. A patent for the XTR Signature Rings was applied for in 2016, and was granted to Burris in 2019.
Mounts for compact sights
Many reflex sights (e.g. red dot sights) and holographic sights have proprietary mounts.
Aimpoint Acro rail: A dovetail rail for attaching a sight via a clamping mechanism, and with a 4 mm wide straight recoil lug groove. The dovetail is approximately 16.5 mm wide, and is radiused so as not to have any sharp edges. The mount is compact enough to be used on pistols, as well as rifles and shotguns. Launched in 2019 together with the sights Aimpoint Acro P-1 and C-1. Also used on Aimpoint Acro C-2 and P-2, as well as Steiner MPS.
Aimpoint Micro standard: First introduced in 2007 on the small tube sight variants of Aimpoint, but today used by other manufacturers as well. Popular on rifles and shotguns, but not on handguns due to its size. The mounting standard uses four screws and one cross slot acting as a recoil lug. Used on red dot sights such as Aimpoint Micro, Vortex Crossfire, Sig Sauer Romeo 4 & 5, and some Holosun Paralow variants.
Aimpoint CompM4 mount: Launched in 2007 with the Aimpoint CompM4 sight. The sight is attached to the mount via two M5 screws from the underside, and the mount has a transverse groove acting as a recoil lug. The Aimpoint Comp line was launched in 1993. The predecessor of the CompM4, CompM2, had a 30 mm ring mount and was introduced in the American military in 2000. Some manufacturers have copied the M4 mount system, but it has mainly been used by Aimpoint.
C-More standard: A mounting standard introduced by C-More Sights. Uses two screws and two circular notches acting as recoil lugs. Used on red dot sights such as Delta Optical MiniDot, Kahles Helia, Vortex Razor and Sig Sauer Romeo3.
Docter/Noblex standard: The mounting pattern which through the 2010s was used by the largest number of manufacturers, perhaps due to the wide range of aftermarket mounts available. The mounting standard uses two screws and four circular notches acting as recoil lugs. Used on red dot sights such as Docter/Noblex sights, Burris Fastfire, Vortex Viper, Leica Tempus, etc.
Shield standard: A proprietary standard used by Shield Sights. Similar in shape to the Noblex/Docter footprint, but with other dimensions. In addition to the Shield red dot sights, it is also used on the Leupold Delta Point Pro.
Trijicon RMR/SRO-standard: Has two screw holes, and two shallow circular notches acting as recoil lugs. Mainly used on the Trijicon RMR and SRO red dot sights, as well as on some Holosun sights.
Other: Some notable red dot sights which have unique footprints not compatible with any of the above are Sig Sauer Romeo 1, Holosun Paralow 403A, Holosun 509T and Swampfox Kraken MRDS. There also exists reflex sights for ring mounts (e.g. Aimpoint CompM2 with a 30 mm tube) or with an integrated Picatinny base.
Link between scope and firearm
Bases
By bases, is usually meant an interconnecting part between the scope and the firearm. For example, a base may have a picatinny attachment on the underside, while the upper side may have either a ring (e.g. 30 mm) or rail mounting (e.g. Zeiss rail). On some assemblies, the upper and lower parts of the base are separate parts that must be screwed together and fastened to a specified torque. A base can thus sometimes constitute a complete scope mount assembly, but is most often used to refer to the lower part of a two-part scope mount assembly.
The firearm interface which sits on the firearm and to which the scope mount is attached is often called the base or rail.
Some types of bases are:
Standard mounts
Picatinny rail: Standardized slot distances.
Weaver rail: Varying width between the slots.
Proprietary and brand specific mounts
Claw mount. Several types, for example Suhl Claw Mounts, Ziegler ZP mount, and others.
Pivot mount. Several types, for example EAW, MAKlick, Steyr Luxus, and others.
Aimpoint Micro, also used by other red dot manufacturers. (Not compatible with Aimpoint Comp or the Aimpoint ACRO mounting standards. See Red dot sight#Mounting types for more red dot mounting standards).
Blaser saddle mount
Contessa 12 mm "Euro rail" mount
Browning X-Lock
Double dovetail, which is rotated and tapped into place. Several types, for example the Leupold Dual Dovetail
Mauser M03 Double Square Mount
Picatinny-against-picatinny (Burris Eliminator)
Pulsar type rail mount. Has some visual similarities with the Zeiss rail, but is incompatible due to a wider base and steeper angle.
Redfield type with windage adjustable mount, also known Redfield Standard Junior. Similar concepts are made by other manufacturers, e.g. "Leupold standard", "Burris TU/SU". Also manufactured by Weaver. Specifications can vary between manufacturers.
Ruger integral type (used on Ruger No. 1, M77, Gunsite Scout, the Ranch series of the Mini-14 and Mini-30, Deerfield carbine, Model 96 (.44 Magnum only) and Ruger PC carbine.)
Sako Optilock, either with rings separate from the bases, or with rings as part of the bases. Bases come in various variantes to fit either Sako tapered dovetail rail (available for three different types of action lengths), Tikka straight dovetail (11 mm or 17 mm), Weaver or Picatinny.
Sako tapered dovetail rail (used on SAKO models Sako 75, Sako 85, L461, L579, S491, M591, L61R, L691, M995 and TRG-S)
Sauer ISI mount (Sauer 303, and a very few editions of Sauer 202)
Sauer SUM mount (Sauer 404)
Schultz & Larsen integral Slide & Lock type
"STANAG" Claw Mount, used on FN FAL, HK G3, HK33, G3SG/1 and MP5. Most STANAG bases must be used with corresponding STANAG rings, but there are also STANAG bases for scopes with rails.
Dovetail rail (for example 11 mm, 17 mm or 19 mm). The flank angle varies, and dovetail rail mounts may therefore be regarded as non-standardized, even for a given witdth.
Trijicon ACOG/VCOG rail
Screw pattern on bases
On receivers without an integrated attachment for mounting a scope, for example, an integrated Picatinny rail, the base is usually screwed on as a separate part. Such mounts are often model-specific to the firearm, and depend on factors such as the radius of the receiver bridge, the type of screw and the distance between the screw holes. A common fastening method is by screws. These are often metric M3.5x0.6 mm or US #6–48 (⌀ 3.5 mm, 0.53 mm pitch) or #8–40 (⌀ 4.2 mm, 0.64 mm pitch).
Many European assemblies use M3.5 screws, such as SAKO Optilock, Recknagel and original CZ rings. Since #6–48 and M3.5x0.6 have near identical diameters and almost equal pitch, there is a potential for confusion, and upon mixing the wrong screw will enter the threads, but will gradually become tighter to screw until the thread is destroyed. In case of damage, the hole must often be drilled and re-threaded, and M4x0.7 or #8–40 may then be relevant alternatives.
Remington 700 pattern
The Remington 700 Short Action (SA) scope base attachment pattern is particularly widespread, and is for example used on models such as:
Remington Model 722, 40x, 78, 740, 742, 760, 710, 721, 722 and 725
Mauser M1996 straight pull and Roesser Titan 16
Mauser SR-97
Sauer 100, Sauer 101, Mauser M18 (not the M12)
Bergara B14 LA
Haenel Jäger 10
Sabatti Rover LA
The Remington 700 Long Action (LA) naturally has a longer distance between the front and rear screw holes, and therefore continuous scope mount assemblies for the 700 LA do not fit on the 700 SA nor the above-mentioned firearms. However, two-piece scope mounts in general interchange for the mentioned models.
List of common screw patterns
Bases with a rounded bottom for mounting on a round receiver bridges should ideally have a slightly smaller radius than the receiver in order to provide two points of contact and give a stable attachment. Conversely, a slightly too large radius on the mount will result in just one point of contact and a less stable attachment.
In the table below, the radius refers to the curvature of the mounting surface on the receiver bridge. The base is often attached with two screws on the front receiver bridge and two screws on the rear receiver bridge, but sometimes with several more screws. The hole distances are measured from center-to-center. Some common hole distances are respectively).
The two front screws are referred to in the list below as screws 1 and 2, and the front hole spacing is thus referred to as «distance 1–2». In the same way, the rear hole distance is called «distance 3–4». The distance between these is largely determined by the receiver length, and is stated here as «distance 2–3»
Other features
Quick release
Quick release (QR) can refer to several different variants of scope mounts which can be mounted and disassembled quickly without tools.
Tilt
In some cases, it may be relevant to add extra inclination to the scope to be able to shoot at longer (or shorter) distance. For example, this is popular for long range shooting, where it is common to use a tilt of 6 mrad (20 MOA). Extra tilt can be achieved several ways, like for example with a tilted Picatiny rail (e.g. 6 mrad tilt), with bases or rings (e.g. 6 mrad tilt) or with special insert rings (e.g. Burris Pos-Align).
Scope height
The height of scope sight can be important for the cheek rest support (often called cheek weld) to gain correct eye placement, as well as for calculating ballistics (e.g. a ballistic table). The latter is particularly relevant at very close ranges (e.g. ), while at longer distances, such as in long range shooting, the scope height has less impact on the ballistic calculations.
The height of a scope sight can be measured in many ways. With regard to ballistic calculations, it is generally only measured from the center of the bore axis to the center of the scope sight (sightline). With regard to cheek support, several methods are used: On firearms with a picatinny rail, the height is measured from the top of the picatinny rail on the firearm. On most other types of bases it is common to measure from the top radius of the receiver bridge.
When the bottom measuring point is determined, the height is then measured up to either the optical center or the bottom of the scope tube, on scopes for ring mounts. The difference between these two measuring methods is distance from the optical center to the bottom of the scope tube, and usually corresponds to half of the tube diameter (e.g. 15 mm on binoculars with a 30 mm tube).
See also
M-LOK
Bipod
References
Mechanical standards
Firearm components | Scope mount | [
"Technology",
"Engineering"
] | 3,932 | [
"Firearm components",
"Mechanical standards",
"Components",
"Mechanical engineering"
] |
55,053,454 | https://en.wikipedia.org/wiki/Classical%20Electrodynamics%20%28book%29 | Classical Electrodynamics is a textbook written by theoretical particle and nuclear physicist John David Jackson. The book originated as lecture notes that Jackson prepared for teaching graduate-level electromagnetism first at McGill University and then at the University of Illinois at Urbana-Champaign. Intended for graduate students, and often known as Jackson for short, it has been a standard reference on its subject since its first publication in 1962.
The book is notorious for the difficulty of its problems, and its tendency to treat non-obvious conclusions as self-evident. A 2006 survey by the American Physical Society (APS) revealed that 76 out of the 80 U.S. physics departments surveyed require all first-year graduate students to complete a course using the third edition of this book.
Overview
Advanced topics treated in the first edition include magnetohydrodynamics, plasma physics, the vector form of Kirchhoff's diffraction theory, special relativity, and radiation emitted by moving and colliding charges. Jackson's choice of these topics is aimed at students interested in theoretical physics in general and nuclear and high-energy physics in particular. The necessary mathematical methods include vector calculus, ordinary and partial differential equations, Fourier series, Green's function, and some special functions (the Bessel functions and Legendre polynomials).
In the second edition, some new topics were added, including the Stokes parameters, the Kramers–Kronig dispersion relations, and the Sommerfeld–Brillouin problem. The two chapters on special relativity were rewritten entirely, with the basic results of relativistic kinematics being moved to the problems and replaced by a discussion on the electromagnetic Lagrangian. Materials on transition and collision radiation and multipole fields were modified. A total of 117 new problems were added.
While the previous two editions use Gaussian units, the third uses SI units, albeit for the first ten chapters only. Jackson wrote that this is in acknowledgement of the fact virtually all undergraduate textbooks on electrodynamics employ SI units and admitted he had "betrayed" an agreement he had with Edward Purcell that they would support each other in the use of Gaussian units. In the third edition, some materials, such as those on magnetostatics and electromagnetic induction, were rearranged or rewritten, while others, such as discussions of plasma physics, were eliminated altogether. One major addition is the use of numerical techniques. More than 110 new problems were added.
Table of contents (third edition)
Introduction and Survey
Chapter 1: Introduction to Electrostatics
Chapter 2: Boundary-value Problems in Electrostatics I
Chapter 3: Boundary-value Problems in Electrostatics II
Chapter 4: Multipoles, Electrostatics of Macroscopic Media, Dielectrics
Chapter 5: Magnetostatics, Faraday's Law, Quasi-static Fields
Chapter 6: Maxwell Equations, Macroscopic Electromagnetism, Conservation Laws
Chapter 7: Plane Electromagnetic Waves and Wave Propagation
Chapter 8: Waveguides, Resonant Cavities, and Optical Fibers
Chapter 9: Radiating Systems, Multipole Fields and Radiation
Chapter 10: Scattering and Diffraction
Chapter 11: Special Theory of Relativity
Chapter 12: Dynamics of Relativistic Particles and Electromagnetic Fields
Chapter 13: Collisions, Energy Loss, and Scattering of Charged Particles, Cherenkov and Transition Radiation
Chapter 14: Radiation by Moving Charges
Chapter 15: Bremsstrahlung, Method of Virtual Quanta, Radiative Beta Processes
Chapter 16: Radiation Damping, Classical Models of Charged Particles
Appendix on Units and Dimensions
Bibliography
Index
Editions
Reception
According to a 2015 review of Andrew Zangwill's Modern Electrodynamics in the American Journal of Physics, "[t]he classic electrodynamics text for the past four decades has been the monumental work by J. D. Jackson, the book from which most current-generation physicists took their first course."
First edition
L.C. Levitt, who worked at the Boeing Scientific Research Laboratory, commented that the first edition offers a lucid, comprehensive, and self-contained treatment of electromagnetism going from Coulomb's law of electrostatics all the way to self-fields and radiation reaction. However, it does not consider electrodynamics in media with spatial dispersion and radiation scattering in bulk matter. He recommended Electrodynamics of Continuous Media by Lev Landau and Evgeny Lifshitz as a supplement.
Second edition
Reviewer Royce Zia from the Virginia Polytechnic Institute wrote that according to many students and professors, a major problem with the first edition of the book was how mathematically heavy the book was, which distracted students from the essential physics. In the second edition, many issues were addressed, more insightful discussions added and misleading diagrams removed. Extended chapters on the applications of electromagnetism brought students closer to research.
Third edition
Physicist Wayne Saslow from Texas A&M University observed that some important new applications were added to the text, such as fiber optics and dielectric waveguides, which are crucial in modern communications technology, and synchrotron light sources, responsible for advances in condensed-matter physics, and that fragments of the excised chapter on magnetohydrodynamics and plasma physics were scattered throughout the text. Saslow argued that Jackson's broad background in electrical engineering, nuclear and high-energy physics served him well in writing this book.
Ronald Fox, a professor of physics at the Georgia Institute of Technology, opined that this book compares well with Classical Electricity and Magnetism by Melba Phillips and Wolfgang Panofsky, and The Classical Theory of Fields by Lev Landau and Evgeny Lifshitz. Classical Electrodynamics is much broader and has many more problems for students to solve. Landau and Lifshitz is simply too dense to be used as a textbook for beginning graduate students. However, the problems in Jackson do not pertain to other branches of physics, such as condensed-matter physics and biophysics. For optimal results, one must fill in the steps between equations and solve a lot of practice problems. Suggested readings and references are valuable. The third edition retains the book's reputation for the difficulty of the exercises it contains, and for its tendency to treat non-obvious conclusions as self-evident. Fox stated that Jackson is the most popular text on classical electromagnetism in the post-war era and that the only other graduate book of comparable fame is Classical Mechanics by Herbert Goldstein. However, while Goldstein's text has been facing competition from Vladimir Arnold's Mathematical Methods of Classical Mechanics, Jackson remained unchallenged (as of 1999). Fox took an advanced course on electrodynamics in 1965 using the first edition of Jackson and taught graduate electrodynamics for the first time in 1978 using the second edition.
Jagdish Mehra, a physicist and historian of science, wrote that Jackson's text is not as good as the book of the same name by Julian Schwinger et al. Whereas Jackson treats the subject as a branch of applied mathematics, Schwinger integrates the two, illuminating the properties of the mathematical objects used with physical phenomena. Unlike Jackson, Schwinger employs variational methods and Green's functions extensively. Mehra took issue with the use of SI units in the third edition, which he considered to be more appropriate for engineering than for theoretical physics. More specifically, he argued that electric and magnetic fields should not have different units because they are components of the electromagnetic field strength tensor. Jackson himself responded to Mehra's review.
Andrew Zangwill, a physicist at the Georgia Institute of Technology, noted the mixed reviews of Jackson after surveying the literature and reviews on Amazon. He pointed out that Jackson often leaves out the details in going from one equation to the next, which is often quite difficult. He stated that four different instructors at his school had worked on an alternative to Jackson using lecture notes developed in roughly a decade with the goal of strengthening the student's understanding of electrodynamics rather than treating it as a topic of applied mathematics.
Thomas Peters from the University of Zürich argued that while Jackson has historically been training students to perform difficult mathematical calculations, a task that is undoubtedly important, there is much more to electrodynamics than this. He wrote that Modern Electrodynamics by Andrew Zangwill offers a "stimulating fresh look" on this subject.
James Russ, an experimental high-energy physicist at the Carnegie Mellon University, was of the opinion that examples are challenging, and the fine points of physics are often left as exercises. He added that Modern Electrodynamics by Andrew Zangwill is a better choice for beginning graduate students, but Jackson offers more comprehensive coverage and remains a fine reference. He recommended having both on the shelf.
See also
List of textbooks in electromagnetism
A Treatise on Electricity and Magnetism
Introduction to Electrodynamics (textbook)
Classical Mechanics (textbook)
General Relativity (textbook)
Notes
References
Further reading
Electromagnetism
Electrodynamics
Physics textbooks
1962 non-fiction books | Classical Electrodynamics (book) | [
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55,053,716 | https://en.wikipedia.org/wiki/GW170817 | GW170817 was a gravitational wave (GW) signal observed by the LIGO and Virgo detectors on 17 August 2017, originating from the shell elliptical galaxy NGC 4993, about 140 million light years away. The signal was produced by the last moments of the inspiral process of a binary pair of neutron stars, ending with their merger. , it is the only GW detection to be definitively correlated with any electromagnetic observation. Unlike the five prior GW detections—which were of merging black holes and thus not expected to have detectable electromagnetic signals—the aftermath of this merger was seen across the electromagnetic spectrum by 70 observatories on 7 continents and in space, marking a significant breakthrough for multi-messenger astronomy. The discovery and subsequent observations of GW170817 were given the Breakthrough of the Year award for 2017 by the journal Science.
The gravitational wave signal, designated GW170817, had an audible duration of approximately 100 seconds, and showed the characteristic intensity and frequency expected of the inspiral of two neutron stars. Analysis of the slight variation in arrival time of the GW at the three detector locations (two LIGO and one Virgo) yielded an approximate angular direction to the source. Independently, a short gamma-ray burst (sGRB) of around 2 seconds, designated GRB 170817A, was detected by the Fermi and INTEGRAL spacecraft beginning 1.7 seconds after the GW merger signal. These detectors have very limited directional sensitivity, but indicated a large area of the sky which overlapped the gravitational wave position. The co-occurrence confirmed a long-standing hypothesis that neutron star mergers describe an important class of sGRB progenitor event.
An intense observing campaign was prioritized, to scan the region indicated by the gravitational wave detection for the expected emission at optical wavelengths. During this search, 11 hours after the signal, an astronomical transient SSS17a, later designated kilonova AT 2017gfo, was observed in the galaxy . It was captured by numerous telescopes, from radio to X-ray wavelengths, over the following days and weeks, and was found to be a fast-moving, rapidly-cooling cloud of neutron-rich material, as expected of debris ejected from a neutron-star merger.
In October 2018, astronomers reported that, in retrospect, an sGRB event detected in 2015 () may represent an earlier case of the same astrophysics reported for GW170817. The similarities between the two events in terms of gamma ray, optical, and x-ray emissions, as well as to the nature of the associated host galaxies, were considered "striking", suggesting that the earlier event may also be the result of a neutron star merger, and that together these may signify a hitherto-unknown class of kilonova transients, making kilonovae more diverse and common in the universe than previously understood. Later research further construed —another sGRB predating GW170817—also to be a kilonova, again based its resemblance to the signature.
Announcement
The observations were officially announced on 16 October 2017 at press conferences at the National Press Club in Washington, D.C., and at the ESO headquarters in Garching bei München in Germany.
Some information was leaked before the official announcement, beginning on 18 August 2017 when astronomer J. Craig Wheeler of the University of Texas at Austin tweeted "New LIGO. Source with optical counterpart. Blow your sox off!" He later deleted the tweet and apologized for scooping the official announcement embargo. Other people followed up on the rumor, and reported that the public logs of several major telescopes listed priority interruptions in order to observe , a galaxy away in the Hydra constellation. The collaboration had earlier declined to comment on the rumors, not adding to a previous announcement that there were several triggers under analysis.
Gravitational wave detection
The gravitational wave signal lasted for approximately 100 seconds starting from a frequency of 24 hertz. It covered approximately 3,000 cycles, increasing in amplitude and frequency to a few hundred hertz in the typical inspiral chirp pattern, ending with the collision received at 12:41:04.4 UTC. It arrived first at the Virgo detector in Italy, then 22 milliseconds later at the LIGO-Livingston detector in Louisiana, United States, and another 3 milliseconds later at the LIGO-Hanford detector in the state of Washington, in the United States. The signal was detected and analyzed by a comparison with a prediction from general relativity defined from the post-Newtonian expansion.
An automatic computer search of the LIGO-Hanford datastream triggered an alert to the LIGO team about 6 minutes after the event. The gamma-ray alert had already been issued at this point (16 seconds post-event), so the timing near-coincidence was automatically flagged. The LIGO/Virgo team issued a preliminary alert (with only the crude gamma-ray position) to astronomers in the follow-up teams at 40 minutes post-event.
Sky localisation of the event required combining data from the three interferometers, but this was delayed by two problems. The Virgo data were delayed by a data transmission problem, and the LIGO Livingston data were contaminated by a brief burst of instrumental noise a few seconds prior to the event peak, which persisted parallel to the rising transient signal in the lowest frequencies. These required manual analysis and interpolation before the sky location could be announced about 4.5 hours after the event. The three detections localized the source to an area of 31 square degrees in the southern sky at 90% probability. More detailed calculations later refined the localization to within 28 square degrees. In particular, the absence of a clear detection by the Virgo interferometer implied that the source was localized within one of its blind spots, a constraint which reduced the search area considerably.
Gamma ray detection
The first electromagnetic signal detected was GRB 170817A, a short gamma-ray burst, detected after the merger time and lasting for about 2 seconds.
GRB 170817A was first recorded by the Fermi Gamma-ray Space Telescope, which issued an automatic alert just 14 seconds after the detection. After the LIGO/Virgo circular 40 minutes later, manual processing of data from the INTEGRAL gamma-ray telescope retrieved independent data for the event. The difference in arrival time between Fermi and INTEGRAL helped to improve the sky localization.
This GRB was relatively faint given the proximity of the host galaxy , possibly due to its jets not being pointed directly toward Earth, but rather at an angle of about 30 degrees off axis.
Electromagnetic follow-up
A series of alerts to other astronomers were issued, beginning with a report of the gamma-ray detection and single-detector LIGO trigger at 13:21 UTC, and a three-detector sky location at 17:54 UTC. These prompted a massive search by many survey and robotic telescopes. In addition to the expected large size of the search area (about 150 times the area of a full moon), this search was challenging because the search area was near the Sun in the sky and thus visible for at most a few hours after dusk for any given telescope.
In total six teams (One-Meter, Two Hemispheres (1M2H), DLT40, VISTA, Master, DECam, and Las Cumbres Observatory (Chile)) imaged the same new source independently in a 90-minute interval. The first to detect optical light associated with the collision was the 1M2H team running the Swope Supernova Survey, which found it in an image of taken 10 hours and 52 minutes after the GW event by the Swope Telescope operating in the near infrared at Las Campanas Observatory, Chile. They were also the first to announce it, naming their detection SSS17a in a circular issued 1226 post-event. The new source was later given an official International Astronomical Union (IAU) designation AT 2017gfo.
The 1M2H team surveyed all galaxies in the region of space predicted by the gravitational wave observations, and identified a single new transient. By identifying the host galaxy of the merger, it is possible to provide an accurate distance consistent with that based on gravitational waves alone.
The detection of the optical and near-infrared source provided a huge improvement in localisation, reducing the uncertainty from several degrees to 0.0001 degree; this enabled many large ground and space telescopes to follow up the source over the following days and weeks.
Within hours after localization, many additional observations were made across the infrared and visible spectrum. Over the following days, the color of the optical source changed from blue to red as the source expanded and cooled.
Numerous optical and infrared spectra were observed; early spectra were nearly featureless, but after a few days, broad features emerged indicative of material ejected at roughly 10 percent of light speed. There are multiple strong lines of evidence that AT 2017gfo is indeed the aftermath of GW170817. The color evolution and spectra are dramatically different from any known supernova. The distance of NGC 4993 is consistent with that independently estimated from the GW signal. No other transient has been found in the GW sky localisation region. Finally, various archive images show nothing at the location of AT 2017gfo, ruling out a foreground variable star in the Milky Way.
The source was detected in the ultraviolet (but not in X-rays) 15.3 hours after the event by the Swift Gamma-Ray Burst Mission. After initial lack of X-ray and radio detections, the source was detected in X-rays 9 days later using the Chandra X-ray Observatory, and 16 days later in the radio using the Karl G. Jansky Very Large Array (VLA) in New Mexico. More than 70 observatories covering the electromagnetic spectrum observed the source.
The radio and X-ray light increased to a peak 150 days after the merger, diminishing afterwards. Astronomers have monitored the optical afterglow of GW170817 using the Hubble Space Telescope. In March 2020, continued X-ray emission at 5-sigma was observed by the Chandra Observatory 940 days after the merger.
Other detectors
No neutrinos consistent with the source were found in follow-up searches by the IceCube and ANTARES neutrino observatories and the Pierre Auger Observatory. A possible explanation for the non-detection of neutrinos is because the event was observed at a large off-axis angle and thus the outflow jet was not directed towards Earth.
Astrophysical origin and products
The origin and properties (masses and spins) of a double neutron star system like GW170817 are the result of a long sequence of complex binary star interactions. The gravitational wave signal indicated that it was produced by the collision of two neutron stars with a total mass of solar masses (). If low spins are assumed, consistent with those observed in binary neutron stars that will merge within a Hubble time, the total mass is . The total energy output of the gravitational wave was ≃63 Foe.
The masses of the progenitor stars have greater uncertainty. The chirp mass, a directly observable parameter which may be roughly equated to the geometric mean of the prior masses, was measured at . The larger progenitor () has a 90% chance of being between , and the smaller () has a 90% chance of being between . Under the low spin assumption, the ranges are for and for , inside a 12 km radius.
The neutron star merger event resulted in a spherically expanding kilonova, characterized by a short gamma-ray burst followed by a longer optical afterglow powered by the radioactive decay of heavy r-process nuclei. GW170817 therefore confirmed neutron star mergers to be viable sites for the r-process, where the neucleosynthesis of around half the isotopes in elements heavier than iron can occur. A total of 16,000 times the mass of the Earth in heavy elements is believed to have formed, including approximately 10 Earth masses just of the two elements gold and platinum.
A hypermassive neutron star was believed to have formed initially, as evidenced by the large amount of ejecta (much of which would have been swallowed by an immediately forming black hole). At first, the lack of evidence for emissions being powered by neutron star spindown, which would occur for longer-surviving neutron stars, suggested it collapsed into a black hole within milliseconds. However, a more detailed analysis of the GW170817 signal tail later found evidence of further features consistent with the seconds-long spindown of an intermediate or remnant hypermassive magnetar, the energy of which was below the estimated sensitivity of the LIGO search algorithms at the time. This was confirmed in 2023 by a statistically independent method of analysis revealing the central engine of GRB170817A. , the precise nature of the ultimately stable remnant remains uncertain.
Scientific importance
Scientific interest in the event was enormous, with dozens of preliminary papers (and almost 100 preprints) published the day of the announcement, including 8 letters in Science, 6 in Nature, and 32 in a special issue of The Astrophysical Journal Letters devoted to the subject. The interest and effort was global: The paper describing the multi-messenger observations is coauthored by almost 4,000 astronomers (about one-third of the worldwide astronomical community) from more than 900 institutions, using more than 70 observatories on all 7 continents and in space.
The event also provided a limit on the difference between the speed of light and that of gravity. Assuming the first photons were emitted between zero and ten seconds after peak gravitational wave emission, the difference between the speeds of gravitational and electromagnetic waves, vGW − vEM, is constrained to between −3×10−15 and +7×10−16 times the speed of light, which improves on the previous estimate by about 14 orders of magnitude.
In addition, GW170817 allowed investigation of the equivalence principle (through Shapiro delay measurement) and Lorentz invariance. The limits of possible violations of Lorentz invariance (values of 'gravity sector coefficients') are reduced by the new observations by up to ten orders of magnitude.
The event also excluded some alternatives to general relativity, including variants of scalar–tensor theory, Hořava–Lifshitz gravity, Dark Matter Emulators, and bimetric gravity, Furthermore, an analysis published in July 2018 used GW170817 to show that gravitational waves propagate fully through the 3+1 curved spacetime described by general relativity, ruling out hypotheses involving "leakage" into higher, non-compact spatial dimensions.
Gravitational wave signals such as GW170817 may be used as a standard siren to provide an independent measurement of the Hubble constant. An initial estimate of the constant derived from the observation is (km/s)/Mpc, broadly consistent with current best estimates. Further studies improved the measurement to (km/s)/Mpc. Together with the observation of future events of this kind, the uncertainty is expected to reach two percent within five years and one percent within ten years.
Electromagnetic observations help support the theory that neutron star mergers contribute to rapid neutron capture (r-process) nucleosynthesis—previously assumed to be associated with supernova explosions—and are therefore the primary source of r-process elements heavier than iron, including gold and platinum. The first identification of r-process elements in a neutron star merger was obtained during a re-analysis of GW170817 spectra. The spectra provided direct proof of strontium production during a neutron star merger. This also provided the most direct proof that neutron stars are made of neutron-rich matter. Since then, several r-process elements have been identified in the ejecta including yttrium, lanthanum and cerium.
In October 2017, Stephen Hawking, in his last broadcast interview, discussed the overall scientific importance of GW170817. In September 2018, astronomers reported related studies about possible mergers of neutron stars (NS) and white dwarfs (WD): including NS-NS, NS-WD, and WD-WD mergers.
See also
Gravitational-wave astronomy
List of gravitational wave observations
Multi-messenger astronomy
Notes
References
External links
Related videos (16 October 2017):
Neutron stars
Gravitational waves
August 2017
2017 in science
2017 in outer space
Hydra (constellation) | GW170817 | [
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55,054,778 | https://en.wikipedia.org/wiki/Plane%20of%20polarization | For light and other electromagnetic radiation, the plane of polarization is the plane spanned by the direction of propagation and either the electric vector or the magnetic vector, depending on the convention. It can be defined for polarized light, remains fixed in space for linearly-polarized light, and undergoes axial rotation for circularly-polarized light.
Unfortunately the two conventions are contradictory. As originally defined by Étienne-Louis Malus in 1811, the plane of polarization coincided (although this was not known at the time) with the plane containing the direction of propagation and the magnetic vector. In modern literature, the term plane of polarization, if it is used at all, is likely to mean the plane containing the direction of propagation and the electric vector, because the electric field has the greater propensity to interact with matter.
For waves in a birefringent (doubly-refractive) crystal, under the old definition, one must also specify whether the direction of propagation means the ray direction (Poynting vector) or the wave-normal direction, because these directions generally differ and are both perpendicular to the magnetic vector (Fig.1). Malus, as an adherent of the corpuscular theory of light, could only choose the ray direction. But Augustin-Jean Fresnel, in his successful effort to explain double refraction under the wave theory (1822 onward), found it more useful to choose the wave-normal direction, with the result that the supposed vibrations of the medium were then consistently perpendicular to the plane of polarization. In an isotropic medium such as air, the ray and wave-normal directions are the same, and Fresnel's modification makes no difference.
Fresnel also admitted that, had he not felt constrained by the received terminology, it would have been more natural to define the plane of polarization as the plane containing the vibrations and the direction of propagation. That plane, which became known as the plane of vibration, is perpendicular to Fresnel's "plane of polarization" but identical with the plane that modern writers tend to call by that name!
It has been argued that the term plane of polarization, because of its historical ambiguity, should be avoided in original writing. One can easily specify the orientation of a particular field vector; and even the term plane of vibration carries less risk of confusion than plane of polarization.
Physics of the term
For electromagnetic (EM) waves in an isotropic medium (that is, a medium whose properties are independent of direction), the electric field vectors (E and D) are in one direction, and the magnetic field vectors (B and H) are in another direction, perpendicular to the first, and the direction of propagation is perpendicular to both the electric and the magnetic vectors. In this case the direction of propagation is both the ray direction and the wave-normal direction (the direction perpendicular to the wavefront). For a linearly-polarized wave (also called a plane-polarized wave), the orientations of the field vectors are fixed (Fig.2).
Because innumerable materials are dielectrics or conductors while comparatively few are ferromagnets, the reflection or refraction of EM waves (including light) is more often due to differences in the electric properties of media than to differences in their magnetic properties. That circumstance tends to draw attention to the electric vectors, so that we tend to think of the direction of polarization as the direction of the electric vectors, and the "plane of polarization" as the plane containing the electric vectors and the direction of propagation.
Indeed, that is the convention used in the online Encyclopædia Britannica, and in Feynman's lecture on polarization. In the latter case one must infer the convention from the context: Feynman keeps emphasizing the direction of the electric (E) vector and leaves the reader to presume that the "plane of polarization" contains that vector — and this interpretation indeed fits the examples he gives. The same vector is used to describe the polarization of radio signals and antennas (Fig.3).
If the medium is magnetically isotropic but electrically non-isotropic (like a doubly-refracting crystal), the magnetic vectors B and H are still parallel, and the electric vectors E and D are still perpendicular to both, and the ray direction is still perpendicular to E and the magnetic vectors, and the wave-normal direction is still perpendicular to D and the magnetic vectors; but there is generally a small angle between the electric vectors E and D, hence the same angle between the ray direction and the wave-normal direction (Fig.1). Hence D, E, the wave-normal direction, and the ray direction are all in the same plane, and it is all the more natural to define that plane as the "plane of polarization".
This "natural" definition, however, depends on the theory of EM waves developed by James Clerk Maxwell in the 1860s — whereas the word polarization was coined about 50 years earlier, and the associated mystery dates back even further.
History of the term
Three candidates
Whether by accident or by design, the plane of polarization has always been defined as the plane containing a field vector and a direction of propagation. In Fig.1, there are three such planes, to which we may assign numbers for ease of reference:
(1) the plane containing both electric vectors and both propagation directions (i.e., the plane normal to the magnetic vectors);
(2a) the plane containing the magnetic vectors and the wave-normal (i.e., the plane normal to D);
(2b) the plane containing the magnetic vectors and the ray (i.e., the plane normal to E).
In an isotropic medium, E and D have the same direction, so that the ray and wave-normal directions merge, and the planes (2a) and (2b) become one:
(2) the plane containing both magnetic vectors and both propagation directions (i.e., the plane normal to the electric vectors).
Malus's choice
Polarization was discovered — but not named or understood — by Christiaan Huygens, as he investigated the double refraction of "Iceland crystal" (transparent calcite, now called Iceland spar). The essence of his discovery, published in his Treatise on Light (1690), was as follows. When a ray (meaning a narrow beam of light) passes through two similarly oriented calcite crystals at normal incidence, the ordinary ray emerging from the first crystal suffers only the ordinary refraction in the second, while the extraordinary ray emerging from the first suffers only the extraordinary refraction in the second. But when the second crystal is rotated 90° about the incident rays, the roles are interchanged, so that the ordinary ray emerging from the first crystal suffers only the extraordinary refraction in the second, and vice versa. At intermediate positions of the second crystal, each ray emerging from the first is doubly refracted by the second, giving four rays in total; and as the crystal is rotated from the initial orientation to the perpendicular one, the brightnesses of the rays vary, giving a smooth transition between the extreme cases in which there are only two final rays.
Huygens defined a principal section of a calcite crystal as a plane normal to a natural surface and parallel to the axis of the obtuse solid angle. This axis was parallel to the axes of the spheroidal secondary waves by which he (correctly) explained the directions of the extraordinary refraction.
The term polarization was coined by Étienne-Louis Malus in 1811. In 1808, in the midst of confirming Huygens' geometric description of double refraction (while disputing his physical explanation), Malus had discovered that when a ray of light is reflected off a non-metallic surface at the appropriate angle, it behaves like one of the two rays emerging from a calcite crystal. As this behavior had previously been known only in connection with double refraction, Malus described it in that context. In particular, he defined the plane of polarization of a polarized ray as the plane, containing the ray, in which a principal section of a calcite crystal must lie in order to cause only ordinary refraction. This definition was all the more reasonable because it meant that when a ray was polarized by reflection (off an isotopic medium), the plane of polarization was the plane of incidence and reflection — that is, the plane containing the incident ray, the normal to the reflective surface, and the polarized reflected ray. But, as we now know, this plane happens to contain the magnetic vectors of the polarized ray, not the electric vectors.
The plane of the ray and the magnetic vectors is the one numbered (2b) above. The implication that the plane of polarization contains the magnetic vectors is still found in the definition given in the online Merriam-Webster dictionary. Even Julius Adams Stratton, having said that "It is customary to define the polarization in terms of E", promptly adds: "In optics, however, the orientation of the vectors is specified traditionally by the 'plane of polarization,' by which is meant the plane normal to E containing both H and the axis of propagation." That definition is identical with Malus's.
Fresnel's choice
In 1821, Augustin-Jean Fresnel announced his hypothesis that light waves are exclusively transverse and therefore always polarized in the sense of having a particular transverse orientation, and that what we call unpolarized light is in fact light whose orientation is rapidly and randomly changing. Supposing that light waves were analogous to shear waves in elastic solids, and that a higher refractive index corresponded to a higher density of the luminiferous aether, he found that he could account for the partial reflection (including polarization by reflection) at the interface between two transparent isotropic media, provided that the vibrations of the aether were perpendicular to the plane of polarization. Thus the polarization, according to the received definition, was "in" a certain plane if the vibrations were perpendicular to that plane!
Fresnel himself found this implication inconvenient; later that year he wrote:
Adopting this hypothesis, it would have been more natural to have called the plane of polarisation that in which the oscillations are supposed to be made: but I wished to avoid making any change in the received appellations.
But he soon felt obliged to make a less radical change. In his successful model of double refraction, the displacement of the medium was constrained to be tangential to the wavefront, while the force was allowed to deviate from the displacement and from the wavefront. Hence, if the vibrations were perpendicular to the plane of polarization, then the plane of polarization contained the wave-normal but not necessarily the ray. In his "Second Memoir" on double refraction, Fresnel formally adopted this new definition, acknowledging that it agreed with the old definition in an isotropic medium such as air, but not in a birefringent crystal.
The vibrations normal to Malus's plane of polarization are electric, and the electric vibration tangential to the wavefront is D (Fig.1). Thus, in terms of the above numbering, Fresnel changed the "plane of polarization" from (2b) to (2a). Fresnel's definition remains compatible with the Merriam-Webster definition, which fails to specify the propagation direction. And it remains compatible with Stratton's definition, because that is given in the context of an isotropic medium, in which planes (2a) and (2b) merge into (2).
What Fresnel called the "more natural" choice was a plane containing D and a direction of propagation. In Fig.1, the only plane meeting that specification is the one labeled "Plane of vibration" and later numbered (1) — that is, the one that modern authors tend to identify with the "plane of polarization". We might therefore wish that Fresnel had been less deferential to his predecessors. That scenario, however, is less realistic than it may seem, because even after Fresnel's transverse-wave theory was generally accepted, the direction of the vibrations was the subject of continuing debate.
"Plane of vibration"
The principle that refractive index depended on the density of the aether was essential to Fresnel's aether drag hypothesis. But it could not be extended to birefringent crystals — in which at least one refractive index varies with direction — because density is not directional. Hence his explanation of refraction required a directional variation in stiffness of the aether within a birefringent medium, plus a variation in density between media.
James MacCullagh and Franz Ernst Neumann avoided this complication by supposing that a higher refractive index corresponded always to the same density but a greater elastic compliance (lower stiffness). To obtain results that agreed with observations on partial reflection, they had to suppose, contrary to Fresnel, that the vibrations were within the plane of polarization.
The question called for an experimental determination of the direction of vibration, and the challenge was answered by George Gabriel Stokes. He defined the plane of vibration as "the plane passing through the ray and the direction of vibration" (in agreement with Fig.1). Now suppose that a fine diffraction grating is illuminated at normal incidence. At large angles of diffraction, the grating will appear somewhat edge-on, so that the directions of vibration will be crowded towards the direction parallel to the plane of the grating. If the planes of polarization coincide with the planes of vibration (as MacCullagh and Neumann said), they will be crowded in the same direction; and if the planes of polarization are normal to the planes of vibration (as Fresnel said), the planes of polarization will be crowded in the normal direction. To find the direction of the crowding, one could vary the polarization of the incident light in equal steps, and determine the planes of polarization of the diffracted light in the usual manner. Stokes performed such an experiment in 1849, and it found in favor of Fresnel.
In 1852, Stokes noted a much simpler experiment that leads to the same conclusion. Sunlight scattered from a patch of blue sky 90° from the sun is found, by the methods of Malus, to be polarized in the plane containing the line of sight and the sun. But it is obvious from the geometry that the vibrations of that light can only be perpendicular to that plane.
There was, however, a sense in which MacCullagh and Neumann were correct. If we attempt an analogy between shear waves in a non-isotropic elastic solid, and EM waves in a magnetically isotropic but electrically non-isotropic crystal, the density must correspond to the magnetic permeability (both being non-directional), and the compliance must correspond to the electric permittivity (both being directional). The result is that the velocity of the solid corresponds to the H field, so that the mechanical vibrations of the shear wave are in the direction of the magnetic vibrations of the EM wave. But Stokes's experiments were bound to detect the electric vibrations, because those have the greater propensity to interact with matter. In short, the MacCullagh-Neumann vibrations were the ones that had a mechanical analog, but Fresnel's vibrations were the ones that were more likely to be detected in experiments.
Modern practice
The electromagnetic theory of light further emphasized the electric vibrations because of their interactions with matter, whereas the old "plane of polarization" contained the magnetic vectors. Hence the electromagnetic theory would have reinforced the convention that the vibrations were normal to the plane of polarization — provided, of course, that one was familiar with the historical definition of the plane of polarization. But if one was influenced by physical considerations alone, then, as Feynman and the Britannica illustrate, one would pay attention to the electric vectors and assume that the "plane" of polarization (if one needed such a concept) contained those vectors.
However, it is not clear that a "plane of polarization" is needed at all: knowing what field vectors are involved, one can specify the polarization by specifying the orientation of a particular vector, or, as Born and Wolf suggest, by specifying the "plane of vibration" of that vector. Hecht also prefers the term plane of vibration (or, more usually, plane-of-vibration), which he defines as the plane of E and the wave-normal, in agreement with Fig.1 above.
Remaining uses
In an optically chiral medium — that is, one in which the direction of polarization gradually rotates as the wave propagates — the choice of definition of the "plane of polarization" does not affect the existence or direction ("handedness") of the rotation. This is one context in which the ambiguity of the term plane of polarization causes no further confusion.
There is also a context in which the original definition might still suggest itself. In a non-magnetic non-chiral crystal of the biaxial class (in which there is no ordinary refraction, but both refractions violate Snell's law), there are three mutually perpendicular planes for which the speed of light is isotropic within the plane provided that the electric vectors are normal to the plane. This situation naturally draws attention to a plane normal to the vibrations as envisaged by Fresnel, and that plane is indeed the plane of polarization as defined by Fresnel or Malus.
In most contexts, however, the concept of a "plane of polarization" distinct from a plane containing the electric "vibrations" has arguably become redundant, and has certainly become a source of confusion. In the words of Born & Wolf, "it is… better not to use this term."
See also
E-plane and H-plane
Plane of incidence
Notes
References
Bibliography
W.S. Aldis, 1879, A Chapter on Fresnel's Theory of Double Refraction, 2nd Ed., Cambridge: Deighton, Bell, & Co. / London: George Bell & Sons.
M. Born and E. Wolf, 1970, Principles of Optics, 4th Ed., Oxford: Pergamon Press.
J.Z. Buchwald, 1989, The Rise of the Wave Theory of Light: Optical Theory and Experiment in the Early Nineteenth Century, University of Chicago Press, .
O. Darrigol, 2012, A History of Optics: From Greek Antiquity to the Nineteenth Century, Oxford, .
A. Fresnel, 1822, De la Lumière (On Light), in J. Riffault (ed.), Supplément à la traduction française de la cinquième édition du "Système de Chimie" par Th.Thomson, Paris: Chez Méquignon-Marvis, 1822, pp.1–137,535–9; reprinted in Fresnel, 1866–70, vol.2, pp.3–146; translated by T. Young as "Elementary view of the undulatory theory of light", Quarterly Journal of Science, Literature, and Art, vol.22 (Jan.–Jun.1827), pp.127–41, 441–54; vol.23 (Jul.–Dec.1827), pp.113–35, 431–48; vol.24 (Jan.–Jun.1828), pp.198–215; vol.25 (Jul.–Dec.1828), pp.168–91, 389–407; vol.26 (Jan.–Jun.1829), pp.159–65.
A. Fresnel, 1827, "Mémoire sur la double réfraction", Mémoires de l'Académie Royale des Sciences de l'Institut de France, vol. (for 1824, printed 1827), pp.45–176; reprinted as "Second mémoire…" in Fresnel, 1866–70, vol.2, pp.479–596; translated by A.W. Hobson as "Memoir on double refraction", in R.Taylor (ed.), Scientific Memoirs, vol. (London: Taylor & Francis, 1852), pp.238–333. (Cited page numbers are from the translation.)
A. Fresnel (ed. H. de Senarmont, E. Verdet, and L. Fresnel), 1866–70, Oeuvres complètes d'Augustin Fresnel (3 volumes), Paris: Imprimerie Impériale; vol.1 (1866), vol.2 (1868), vol.3 (1870).
E. Hecht, 2017, Optics, 5th Ed., Pearson Education, .
C. Huygens, 1690, Traité de la Lumière (Leiden: Van der Aa), translated by S.P. Thompson as Treatise on Light, University of Chicago Press, 1912; Project Gutenberg, 2005. (Cited page numbers match the 1912 edition and the Gutenberg HTML edition.)
B. Powell (July 1856), "On the demonstration of Fresnel's formulas for reflected and refracted light; and their applications", Philosophical Magazine and Journal of Science, Series 4, vol.12, no.76, pp.1–20.
J.A. Stratton, 1941, Electromagnetic Theory, New York: McGraw-Hill.
E. T. Whittaker, 1910, A History of the Theories of Aether and Electricity: From the Age of Descartes to the Close of the Nineteenth Century, London: Longmans, Green, & Co.
Light
Optics
Physical optics
Polarization (waves)
Electromagnetic radiation
Antennas (radio)
History of physics
Planes (geometry) | Plane of polarization | [
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"Waves",
"Radiation",
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" molecular",
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55,055,036 | https://en.wikipedia.org/wiki/NGC%204993 | NGC 4993 (also catalogued as NGC 4994 in the New General Catalogue) is a lenticular galaxy located about 140 million light-years away in the constellation Hydra. It was discovered on 26 March 1789 by William Herschel and is a member of the NGC 4993 Group.
NGC 4993 was the site of GW170817, a collision of two neutron stars, the first astronomical event detected in both electromagnetic and gravitational radiation, a discovery given the Breakthrough of the Year award for 2017 by the journal Science. Detecting a gravitational wave event associated with the gamma-ray burst provided direct confirmation that binary neutron star collisions produce short gamma-ray bursts.
Physical characteristics
NGC 4993 has several concentric shells of stars and a large dust lane—with a diameter of approximately a few kiloparsecs—which surrounds the nucleus and is stretched out into an "s" shape. The dust lane appears to be connected to a small dust ring with a diameter of ~. These features in NGC 4993 may be the result of a recent merger with a gaseous late-type galaxy that occurred about 400 million years ago. However, Palmese et al. suggest that the galaxy involved in the merger was a gas-poor galaxy.
Dark matter content
NGC 4993 has a dark matter halo with an estimated mass of .
Globular clusters
NGC 4993 has an estimated population of 250 globular clusters.
The luminosity of NGC 4993 indicates that the globular cluster system surrounding the galaxy may be dominated by metal-poor globular clusters.
Supermassive black hole
NGC 4993 has a supermassive black hole with an estimated mass of roughly 80 to 100 million solar masses ().
Galactic nucleus activity
The presence of weak O III, NII and SII emission lines in the nucleus of NGC 4993 and the relatively high ratio of [NII]λ6583/Hα suggest that NGC 4993 is a low-luminosity AGN (LLAGN). The activity may have been triggered by gas from the late-type galaxy as it merged with NGC 4993.
Neutron star merger observations
In August 2017, rumors circulated regarding a short gamma-ray burst designated GRB 170817A, of the type conjectured to be emitted in the collision of two neutron stars. On 16 October 2017, the LIGO and Virgo collaborations announced that they had detected a gravitational wave event, designated GW170817. The gravitational wave signal matched prediction for the merger of two neutron stars, two seconds before the gamma-ray burst. The gravitational wave signal, which had a duration of about 100 seconds, was the first gravitational wave detection of the merger of two neutron stars.
An optical transient, (also known as SSS 17a), was detected in NGC 4993 11 hours after the gravitational wave and gamma-ray signals, allowing the location of the merger to be determined. The optical emission is thought to be due to a kilonova. The discovery of AT 2017gfo was the first observation (and first localisation) of an electromagnetic counterpart to a gravitational wave source.
GRB 170817A was a gamma-ray burst (GRB) detected by NASA's Fermi and ESA's INTEGRAL on 17 August 2017. Although only localized to a large area of the sky, it is believed to correspond to the other two observations, in part due to its arrival time 1.7 seconds after the GW event.
See also
Gravitational-wave astronomy
List of gamma-ray bursts
List of gravitational wave observations
Neil Gehrels Swift Observatory
Ultra-Fast Flash Observatory Pathfinder
References
External links
GRB 170817A – NASA/IPAC Extragalactic Database (NED)
GRB 170817A – Max Planck Institute for Extraterrestrial Physics (MPE)
GRB 170817A - INTEGRAL Science Data Center (ISDC)
The galaxy NGC 4993 in the constellation of Hydra Starmap
Active galaxies
Astronomical objects discovered in 1789
Elliptical galaxies
Lenticular galaxies
Shell galaxies
Hydra (constellation)
4993
45657 | NGC 4993 | [
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] | 840 | [
"Hydra (constellation)",
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55,058,695 | https://en.wikipedia.org/wiki/Service%20automation%20framework | The Service Automation Framework (SAF) is a set of best practices for the automated delivery of services. The concept builds further on the self-service practices of ITIL and IT Service Management. In its current form, the SAF is published as in a series of volumes, covering different processes of service automation. The Service Automation Framework is maintained and updated by the Service Automation Framework Alliance, an independent body of knowledge for the advancement of service automation.
SAF describes processes, procedures, tasks, and checklists which are not organization-specific, but can be applied by an organization for establishing integration with the organization's strategy, delivering value, and maintaining a minimum level of competency. It allows the organization to establish a baseline from which it can plan, implement, and measure. It is used to demonstrate compliance and to measure improvement. Since December 2016, APMG-International provides the examination for the SAF.
References
IT service management | Service automation framework | [
"Technology"
] | 190 | [
"Computer industry",
"IT service management"
] |
55,059,510 | https://en.wikipedia.org/wiki/Immunological%20memory | Immunological memory is the ability of the immune system to quickly and specifically recognize an antigen that the body has previously encountered and initiate a corresponding immune response. Generally, they are secondary, tertiary and other subsequent immune responses to the same antigen. The adaptive immune system and antigen-specific receptor generation (TCR, antibodies) are responsible for adaptive immune memory.
After the inflammatory immune response to danger-associated antigen, some of the antigen-specific T cells and B cells persist in the body and become long-living memory T and B cells. After the second encounter with the same antigen, they recognize the antigen and mount a faster and more robust response. Immunological memory is the basis of vaccination. Emerging resources show that even the innate immune system can initiate a more efficient immune response and pathogen elimination after the previous stimulation with a pathogen, respectively with PAMPs or DAMPs. Innate immune memory (also called trained immunity) is neither antigen-specific nor dependent on gene rearrangement, but the different response is caused by changes in epigenetic programming and shifts in cellular metabolism. Innate immune memory was observed in invertebrates as well as in vertebrates.
Adaptive immune memory
Development of adaptive immune memory
Immunological memory occurs after a primary immune response against the antigen. Immunological memory is thus created by each individual, after a previous initial exposure, to a potentially dangerous agent. The course of secondary immune response is similar to primary immune response. After the memory B cell recognizes the antigen it presents the peptide: MHC II complex to nearby effector T cells. That leads to activation of these cells and rapid proliferation of cells. After the primary immune response has disappeared, the effector cells of the immune response are eliminated.
However, antibodies that were previously created in the body remain and represent the humoral component of immunological memory and comprise an important defensive mechanism in subsequent infections. In addition to the formed antibodies in the body there remains a small number of memory T and B cells that make up the cellular component of the immunological memory. They stay in blood circulation in a resting state and at the subsequent encounter with the same antigen these cells are able to respond immediately and eliminate the antigen. Memory cells have a long life and last up to several decades in the body.
Immunity to chickenpox, measles, and some other diseases lasts a lifetime. Immunity to many diseases eventually wears off. The immune system's response to a few diseases, such as dengue, counterproductively worsens the next infection (antibody-dependent enhancement).
As of 2019, researchers are still trying to find out why some vaccines produce life-long immunity, while the effectiveness of other vaccines drops to zero in less than 30 years (for mumps) or less than six months (for H3N2 influenza).
Evolution of adaptive immune memory
The evolutionary invention of memory T and B cells is widespread; however, the conditions required to develop this costly adaptation are specific. First, in order to evolve immune memory the initial molecular machinery cost must be high and will demand losses in other host characteristics. Second, middling or long lived organisms have higher chance of evolving such apparatus. The cost of this adaption increases if the host has a middling lifespan as the immune memory must be effective earlier in life.
Furthermore, research models show that the environment plays an essential role in the diversity of memory cells in a population. Comparing the influence of multiple infections to a specific disease as opposed to disease diversity of an environment provide evidence that memory cell pools accrue diversity based on the number of individual pathogens exposed, even at the cost of efficiency when encountering more common pathogens. Individuals living in isolated environments such as islands have a less diverse population of memory cells, which are, however, present with sturdier immune responses. That indicates that the environment plays a large role in the evolution of memory cell populations.
Previously acquired immune memory can be depleted by measles in unvaccinated children, leaving them at risk of infection by other pathogens in the years after infection.
Memory B cells
Memory B cells are plasma cells that are able to produce antibodies for a long time. Unlike the naive B cells involved in the primary immune response the memory B cell response is slightly different. The memory B cell has already undergone clonal expansion, differentiation and affinity maturation, so it is able to divide multiple times faster and produce antibodies with much higher affinity (especially IgG).
In contrast, the naive plasma cell is fully differentiated and cannot be further stimulated by antigen to divide or increase antibody production. Memory B cell activity in secondary lymphatic organs is highest during the first 2 weeks after infection. Subsequently, after 2 to 4 weeks its response declines. After the germinal center reaction the memory plasma cells are located in the bone marrow which is the main site of antibody production within the immunological memory.
Memory T cells
Memory T cells can be both CD4+ and CD8+. These memory T cells do not require further antigen stimulation to proliferate; therefore, they do not need a signal via MHC. Memory T cells can be divided into two functionally distinct groups based on the expression of the CCR7 chemokine receptor. This chemokine indicates the direction of migration into secondary lymphatic organs. Those memory T cells that do not express CCR7 (these are CCR7-) have receptors to migrate to the site of inflammation in the tissue and represent an immediate effector cell population. These cells were named memory effector T cells (TEM). After repeated stimulation they produce large amounts of IFN-γ, IL-4 and IL-5. In contrast, CCR7 + memory T cells lack proinflammatory and cytotoxic function but have receptors for lymph node migration. These cells were named central memory T cells (TCM). They effectively stimulate dendritic cells, and after repeated stimulation they are able to differentiate in CCR7- effector memory T cells. Both populations of these memory cells originate from naive T cells and remain in the body for several years after initial immunization.
Experimental techniques used to study these cells include measuring antigen-stimulated cell proliferation and cytokine release, staining with peptide-MHC multimers or using an activation-induced marker (AIM) assay.
Innate immune memory
Many invertebrates such as species of fresh water snails, copepod crustaceans, and tapeworms have been observed activating innate immune memory to instigate a more efficient immune response to second encounter with specific pathogens, despite missing an adaptive branch of the immune system. RAG1-deficient mice without functional T and B cells were able to survive the administration of a lethal dose of Candida albicans when exposed previously to a much smaller amount, showing that vertebrates also retain this ability. Despite not having the ability to manufacture antibodies like the adaptive immune system, innate immune system has immune memory properties as well. Innate immune memory (trained immunity) is defined as a long-term functional reprogramming of innate immune cells evoked by exogenous or endogenous insults and leading to an altered response towards a second challenge after returning to a non-activated state.
When innate immune cells receive an activation signal; for example, through recognition of PAMPs with PRRs, they start the expression of proinflammatory genes, initiate an inflammatory response, and undergo epigenetic reprogramming. After the second stimulation, the transcription activation is faster and more robust. Immunological memory was reported in monocytes, macrophages, NK cells, ILC1, ILC2, and ILC3 cells. Concomitantly, some nonimmune cells, for example, epithelial stem cells on barrier tissues, or fibroblasts, change their epigenetic state and respond differently after priming insult.
Mechanism of innate immune memory
At the steady state, unstimulated cells have reduced biosynthetic activities and more condensed chromatin with reduced gene transcription. The interaction of exogenous PAMPs (β-glucan, muramyl peptide) or endogenous DAMPs (oxidized LDL, uric acid) with PRR initiates a cellular response. Triggered Intracellular signaling cascades lead to the upregulation of metabolic pathways such as glycolysis, Krebs cycle, and fatty acid metabolism. An increase in metabolic activity provides cells with energy and building blocks, which are needed for the production of signaling molecules such as cytokines and chemokines.
Signal transduction changes the epigenetic marks and increases chromatin accessibility, to allow binding of transcription factors and start transcription of genes connected with inflammation. There is an interplay between metabolism and epigenetic changes because some metabolites such as fumarate and acetyl-CoA can activate or inhibit enzymes involved in chromatin remodeling. After the stimulus let up, there is no need for immune factors production, and their expression in immune cells is terminated. Several epigenetic modifications created during stimulation remain. Characteristic epigenetic rewiring in trained cells is the accumulation of H3K4me3 on immune genes promoters and the increase of H3k4me1 and H3K27ac on enhancers. Additionally, cellular metabolism does not return to the state before stimulation, and trained cells remain in a prepared state. This status can last from weeks to several months and can be transmitted into daughter cells. Secondary stimulation induces a new response, which is faster and stronger.
Evolution of innate immune memory
Immune memory brings a major evolutionary advantage when the organism faces repeated infections. Inflammation is very costly, and increased effectivity of response accelerates pathogen elimination and prevents damage to the host's own tissue. Classical adaptive immune memory evolved in jawed vertebrates and in jawless fish (lamprey), which is approximately just 1% of living organisms. Some form of immune memory is, therefore, reported in other species. In plants and invertebrates, faster kinetics, increased magnitude of immune response and an improved survival rate can be seem after secondary infection encounters. Immune memory is common for the vast majority of biodiversity on earth.
It has been proposed that immune memory in innate and adaptive immunity represents an evolutionary continuum in which a more robust immune response evolved first, mediated by epigenetic reprogramming. In contrast, specificity through antigen-specific receptors evolved later in some vertebrates.
Evolutionary mechanisms leading to the development of immunological memory
The emergence of the adaptive immune system is rooted in the deep history of evolution dating back roughly 500 million years. Investigations and recent studies found that two major events led to the emergence of the same. These two macroevolutionary events were the origin of RAG and two whole rounds of genome duplication (WGD).The early origins and evidence for emergence of features resembling AIS dates to the era where jawed and jawless vertebrates diverged phylogenetically. Early investigations around the 1970s led to the discovery of unique inverted repeat flanking signal sequences while groups studied the RAG genome. These so-called RAG transposons invaded regions of genome which may have been involved in AIS. Culmination of several works and review suggests that these disruptions could have been selected for a rearrangement to maintain genomic integrity which ultimately led to mechanisms like RAG diversifications in AIS. This discovery led to the hypothesis that there was an invasion event of a regulatory element-like region because these repeats resembled a remnant transposable element. This invasion was argued to be necessary for the emergence of BCR and TCR-dependent immunity as we see now in all gnathostomes .According to recent scientific findings around 450-500mya the vertebrate genome went through two rounds of whole genome duplication. This is usually referred to as the “2R hypothesis”. Such intense genomic events lead to gene sub-functionalization, neofunctionalization or in many cases lead to loss of functions. Ohno, 40 years ago proposed that the evolutionary events which led to whole genome duplication was key for the emergence of the diversity we see in adaptive immunity and memory. Further works illustrate that newer genic regions which arose because of this duplication event, are major contributors to today's adaptive immune systems which control immunological memory in gnathostomes. Okada’s work on investigating ohnologues that arose from WGD is clear proof of the same, that today AIS systems are remnants of the WGD events
See also
Immunity (medical)
Seroconversion
Serostatus
Virgin soil epidemic
References
Immune system | Immunological memory | [
"Biology"
] | 2,600 | [
"Immune system",
"Organ systems"
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55,059,805 | https://en.wikipedia.org/wiki/Unit%201855 | Unit 1855 was a unit for human experimentation that belonged to the central Epidemic Prevention and Water Purification Department of the North China Army of the Imperial Japanese Army, stationed in Beijing between 1938 and 1945.
Unit 1855 was established by the North China Army in 1938. The unit was located in a facility not far from the Temple of Heaven in Beijing, and had a staff of about 2000 men. The unit was commanded by the surgeon Col. Nishimura Yeni, who reported directly to Shirō Ishii at Unit 731.
According to the testimony of the Korean Choi Hyung Shi, who worked as an interpreter with Unit 1855 between 1942 and 1943, the Unit conducted experiments with plague, cholera and typhus on Chinese and Korean immigrants to China:
"When I first arrived there, some one hundred prisoners were already in the cells. Whenever the Japanese doctors made contact with the people being tested, they always did so through an interpreter. The test subjects were infected with plague, cholera and typhus. Those not yet infected were kept in different rooms. There were large mirrors in the rooms with the subjects so that those undergoing the testing could be observed better. I spoke with the prisoners using a microphone and looking through the glass panel, interpreted the questions from the doctors: "Do you have diarrhea? Do you have a headache? Do you feel chilly?" The doctors made careful records of all answers. With the typhus test, ten people were forced to drink a mixture of the germs, and five were administered the vaccine. The two groups were separated from each other. The vaccine proved effective with all five to whom it was administered. The other five suffered horribly. In the plague tests, the prisoners suffered with chills and fever, and groaned in pain...until they died. From what I saw, one person was killed every day."
It has been estimated, that Unit 1855 killed about 1000 people between 1938 and 1945.
The unit evacuated the facilities in Beijing during the Japanese defeat in 1945, and the Chinese entered the building, which was not destroyed and was still standing as of 1996.
Branches
Unit 1855 had a branch in Chinan, which was a combination of prison and experiment center.
References
Japanese biological weapons program
Imperial Japanese Army
Japanese prisoner of war and internment camps
Japanese human subject research
Beijing in World War II
Medical experimentation on prisoners of war
Japanese war crimes in China | Unit 1855 | [
"Chemistry",
"Biology"
] | 481 | [
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55,062,424 | https://en.wikipedia.org/wiki/Nokia%20130%20%282017%29 | Nokia 130 (2017) is a Nokia-branded mobile phone developed by HMD Global. It was released on 17 July 2017.
Specifications
The phone has almost the same features as the predecessor. It is slightly larger (111.5 x 48.4 x 14.2 mm compared to 106 x 45.5 x 13.9 mm), has small optical design changes, image support, a file manager, and more games, like Air Strike, Danger Dash, Ninja Up, Sky Gift and Nitro Racing. It also features a rear-camera and an LED-flashlight at the top.
Even though the camera can be used to take photos and record videos, the resolution is limited to 640 x 480 pixel for images and 176 x 144 pixel for videos. Furthermore, by default, videos are recorded in only 9.598 frames per second and the built in memory of 8 MB holds less than 2 minutes of video footage. Neither the used image or video resolution nor their quality can be changed.
The Nokia 130 uses a Mini-SIM card for the Single as well as the Dual-SIM model and has a dedicated microSDHC card slot.
Even though the Nokia 130 has a camera, can display images and supports GPRS as well as EDGE, it is not able to display images that were received in a MMS-messages. The phone does support Bluetooth 3.0, but it can neither be paired with iOS devices nor can it receive images via a Bluetooth connection when no microSD card is inserted.
The phone does not have a front-camera, and does not include WLAN nor GPS.
Gallery
References
External links
130 (2017)
Mobile phones introduced in 2017
Mobile phones with user-replaceable battery | Nokia 130 (2017) | [
"Technology"
] | 347 | [
"Mobile technology stubs",
"Mobile phone stubs"
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55,062,864 | https://en.wikipedia.org/wiki/EZCast | EZCast is a line of digital media players, built by Actions Microelectronics, that allows users to mirror media content from smart devices, including mobile devices, personal computers, and project to high-definition televisions.
History
The first generation of EZCast was developed in 2013, shipped 1 million units within a year, and accumulated more than 2 million EZCast app users worldwide. The latest device in the family, called EZCast 4K, was launched in November 2016 which supports 4K HEVC video streaming.
EZCast technology is built into a dongle that interacts with EZCast app to stream content from smart devices, and it works across Android, ChromeOS, iOS, macOS, Windows and Windows Phone.
EZCast SDK has been released to enable third party development on Android and iOS.
In 2018 became possible to voice control EZCast 2 and EZCast 4K devices using Google Assistant.
Technology
EZCast devices all come equipped with Actions Microelectronics SoCs and Linux-based software that supports Miracast/DLNA and/or USB video for iOS and Android.
References
Electronics companies of Taiwan
Wireless display technologies | EZCast | [
"Technology"
] | 242 | [
"Wireless networking",
"Wireless display technologies"
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55,063,733 | https://en.wikipedia.org/wiki/Insilico%20Medicine | Insilico Medicine is a biotechnology company headquartered in Boston, Massachusetts, with additional facilities in Pak Shek Kok, Hong Kong in Hong Kong Science Park near the Chinese University of Hong Kong, and in New York, at The Cure by Deerfield. The company combines genomics, big data analysis, and deep learning for in silico drug discovery.
History
In 2011, Alex Zhavoronkov published an article in the journal PLOS One with Dr. Charles Cantor, previously director of the Human Genome Project at the Department of Energy (DOE) and founder of Sequenom on the International Aging Research Portfolio (IARP), establishing a public data set tracking government research funding and outcomes. This work formed the basis for an artificial intelligence (AI) pharmacological analysis platform.
Zhavoronkov assertedly founded Insilico Medicine in 2014, as an alternative to animal testing for research and development programs in the pharmaceutical industry, using AI and deep-learning techniques to analyze how a compound will affect cells and what drugs can be used to treat the cells in addition to possible side effects. Through its Pharma.AI division, the company provides machine learning services to different pharmaceutical, biotechnology, and skin care companies. Insilico is known for hiring mainly through hackathons such as their own MolHack online hackathon.
The company has multiple collaborations in the applications of next-generation artificial intelligence technologies such as the generative adversarial networks (GANs) and reinforcement learning to the generation of novel molecular structures with desired properties. In 2016, Insilico published an algorithm that it called the "Insilico Pathway Activation Network Decomposition Analysis" or "iPANDA" algorithm, asserted to allow researchers "to quickly and efficiently analyze signaling and metabolic pathway perturbation states using gene expression data". In conjunction with Alan Aspuru-Guzik's group at Harvard, they published a journal article about an improved architecture for molecular generation which combines GANs, reinforcement learning, and a differentiable neural computer.
In 2017, Insilico was named one of the Top five AI companies by NVIDIA for its potential for social impact. Insilico has resources in Belgium, Russia, and the UK and hires talent through hackathons and other local competitions. By mid-2017, Insilico had raised $8.26 million in funding from investors including Deep Knowledge Ventures, JHU A-Level Capital, Jim Mellon, and Juvenescence. In 2019 it raised another $37 million from Fidelity Investments, Eight Roads Ventures, Qiming Venture Partners, WuXi AppTec, Baidu, Sinovation, Lilly Asia Ventures, Pavilion Capital, BOLD Capital, and other investors.
The company "focused exclusively on drug discovery until 2019 when it began developing its own therapeutics". In January 2021, Insilico entered into a partnership with Fosun Pharma, to facilitate entry into the Chinese market. Later in 2021 after developing a novel preclinical candidate molecule for a novel target, the company announced a series C $255 million megaround from Warburg Pincus, Sequoia Capital, Orbimed, Mirae Asset Financial Group, and over 25 biotechnology, AI, and pharmaceutical investors. By mid-2021, it claimed to have nominated eight preclinical candidates. Another $60 million in new Series D financing was raised in 2022. it was reported that over $400 million had been invested in the company. In 2023, Zhavoronkov stated that he "moved the company's R&D to China to capitalize on 'half a trillion dollars' worth of infrastructure and hundreds of thousands of scientists [provided by the government] to enable AI-designed drugs". In mid-2024, it was reported that the corporate headquarters had relocated to Boston, Massachusetts. In November 2024, Insilico was named one of the top 50 AI innovators by Fortune magazine.
Research
The company "applies DL, big data, and genomis for in silico drug discovery" for various conditions. It has sought to develop AI to "identify novel drug targets for untreated diseases", and has pursued dual-purpose therapeutics, "going after a specific disease or several diseases while targeting ageing at the same time".
In 2019, the company in partnership with researchers at the University of Toronto, used AI to design potential new drugs. One was reported to have shown promising initial results when tested in mice. Research areas for therapeutics have included fibrosis, immunology, oncology and the central nervous system. To demonstrate the capacity of their proprietary AI platforms, the company published two projects on identifying therapeutic targets for ageing and amyotrophic lateral sclerosis in 29 March and 28 June 2022, respectively.
The company has collaborated with scientists at the University of Chicago, George Mason University, and University of Liverpool, focusing on ageing. For ALS, the company worked with researchers from Answer ALS, Johns Hopkins University School of Medicine, Harvard Medical School, Mayo Clinic, Tsinghua University, and 4B Technologies Limited. In 2023, it was reported that Insilico had initiated "one of the first mid-stage human trials of a drug discovered and designed by artificial intelligence".
Outside of human drugs, in 2021 the company partnered with Swiss company Syngenta weedkillers.
References
External links
Deborah Borfitz, "Insilico Medicine’s AI-Driven Platform Pushes The Envelope Of Drug Discovery", Bio-IT World (15 December 2022).
Biotechnology companies of Hong Kong
Drug discovery companies
Biogerontology organizations
Life extension organizations
Organizations established in 2014
Warburg Pincus companies | Insilico Medicine | [
"Chemistry"
] | 1,164 | [
"Drug discovery companies",
"Drug discovery"
] |
61,297,896 | https://en.wikipedia.org/wiki/K2-58 | K2-58 (also designated as EPIC 206026904) is a G-type main-sequence star in the constellation of Aquarius, approximately 596 light-years from the Solar System. The star is metal-rich, having 155% of the Solar abundance of elements heavier than helium. The star is located in a region where a hypothetical observer in the K2-58 system can see Venus transiting the sun.
Planetary system
The planetary system has three confirmed exoplanets, named K2-58 b, K2-58 c, and K2-58 d, discovered in 2016.
References
Aquarius (constellation)
Planetary systems with three confirmed planets
K-type main-sequence stars
J22151722-1402593
Planetary transit variables | K2-58 | [
"Astronomy"
] | 159 | [
"Constellations",
"Aquarius (constellation)"
] |
61,300,301 | https://en.wikipedia.org/wiki/Wolf%20distribution | Wolf distribution is the species distribution of the wolf (Canis lupus). Originally, wolves occurred in Eurasia above the 12th parallel north and in North America above the 15th parallel north. However, deliberate human persecution has reduced the species' range to about one-third, because of livestock predation and fear of wolf attacks on humans. The species is now extirpated in much of Western Europe, Mexico, and the contiguous United States, and completely from the British Isles and the Japanese archipelago. In modern history, the gray wolf occurs mostly in wilderness and remote areas, particularly in Canada, Alaska, the Northern United States, Europe and Asia from about the 75th parallel north to the 12th parallel north. Wolf population declines have been arrested since the 1970s, and have fostered recolonization and reintroduction in parts of its former range, due to legal protection, changes in land-use and rural human population shifts to cities. Competition with humans for livestock and game species, concerns over the danger posed by wolves to people, and habitat fragmentation pose a continued threat to the species. Despite these threats, because of the gray wolf's relatively widespread range and stable population, it is classified as Least Concern on the IUCN Red List.
In Africa the population of wolves is limited to the northern regions with the African golden wolf (Canis lupaster) north of the Sahara and the Ethiopian wolf (Canis simensis) in Ethiopia.
Europe
Decline
Wolf populations strongly declined across Europe during the 18th and 19th centuries largely due to human persecution, and by the End of World War II in Europe they had been extirpated from all of Central Europe and almost all of Northern Europe.
The extirpation of Northern Europe's wolves first became an organized effort during the Middle Ages, and continued until the late 19th century. In England, wolf eradication was enforced by legislation, and the last wolf was killed in the early 16th century during the reign of Henry VII (reigned 1485–1509). Wolves lasted longer in Scotland, where they sheltered in vast tracts of forest, which were subsequently burned down. Wolves managed to survive in the forests of Braemar and Sutherland until 1684. The extirpation of wolves in Ireland followed a similar course, with the last wolf believed to have been killed in 1786. A wolf bounty was introduced in Sweden in 1647, after the extirpation of moose and reindeer forced wolves to feed on livestock. The Sami extirpated wolves in northern Sweden in organized drives. By 1960, few wolves remained in Sweden, because of the use of snowmobiles in hunting them, with the last specimen being killed in 1966. The gray wolf was extirpated in Denmark in 1772 and Norway's last wolf was killed in 1973. The species was decimated in 20th century Finland, despite regular dispersals from Russia. The gray wolf was only present in the eastern and northern parts of Finland by 1900, though its numbers increased after World War II.
In Central Europe, wolves were dramatically reduced in number during the early 19th century, because of organized hunts and reductions in ungulate populations. In Bavaria, the last wolf was killed in 1847, and had disappeared from the Rhine regions by 1899. In Switzerland, wolves were extirpated in the 20th century; they are naturally coming back from Italy since the 1990s. In 1934, Nazi Germany became the first state in modern history to place the wolf under protection, though the species was already extirpated in Germany at this point. The last free-living wolf to be killed on the soil of present-day Germany before 1945 was the so-called "Tiger of Sabrodt", which was shot near Hoyerswerda, Lusatia (then Lower Silesia) in 1904. Today, wolves have returned to the area. Wolf hunting in France was first institutionalized by Charlemagne between 800 and 813, when he established the louveterie, a special corps of wolf hunters. The louveterie was abolished after the French Revolution in 1789, but was reestablished in 1814. In 1883, up to 1,386 wolves were killed, with many more by poison.
In Eastern Europe, some wolves remained because of the area's contiguity with Asia and its large forested areas. However, Eastern European wolf populations were reduced to very low numbers by the late 19th century. Wolves were extirpated in Slovakia during the first decade of the 20th century and, by the mid-20th century, could only be found in a few forested areas in eastern Poland. Wolves in the eastern Balkans benefitted from the region's contiguity with the former Soviet Union and large areas of plains, mountains and farmlands. Wolves in Hungary occurred in only half the country around the start of the 20th century, and were largely restricted to the Carpathian Basin. Wolf populations in Romania remained largely substantial, with an average of 2,800 wolves being killed annually out of a population of 4,600 from 1955 to 1965. An all-time low was reached in 1967, when the population was reduced to 1,550 animals. The extirpation of wolves in Bulgaria was relatively recent, as a previous population of about 1,000 animals in 1955 was reduced to about 100–200 in 1964. In Greece, the species disappeared from the southern Peloponnese in 1930. Despite periods of intense hunting during the 18th century, wolves never disappeared in the western Balkans, from Albania to the former Yugoslavia. Organized persecution of wolves began in Yugoslavia in 1923, with the setting up of the Wolf Extermination Committee (WEC) in Kočevje, Slovenia. The WEC was successful in reducing wolf numbers in the Dinaric Alps.
In Southern Europe, some wolves remained because of greater cultural tolerance of the species. Wolf populations only began declining in the Iberian Peninsula in the early 19th century, and was reduced by a half of its original size by 1900. Wolf bounties were regularly paid in Italy as late as 1950. Wolves were extirpated in the Alps by 1800, and numbered only 100 by 1973, inhabiting only 3–5% of their former Italian range.
Recovery
The recovery of European wolf populations began after the 1950s, when traditional pastoral and rural economies declined and thus removed the need to heavily persecute wolves. By the 1980s, small and isolated wolf populations expanded in the wake of decreased human density in rural areas and the recovery of wild prey populations.
The gray wolf has been fully protected in Italy since 1976, and now holds a population of over 1,269–1,800. Italian wolves entered France's Mercantour National Park in 1993, and at least fifty wolves were discovered in the western Alps in 2000. By 2013 the 250 wolves in the Western Alps imposed a significant burden on traditional sheep and goat husbandry with a loss of over 5,000 animals in 2012. There are approximately 2,000 wolves inhabiting the Iberian Peninsula, of which 150 reside in northeastern Portugal. In Spain, the species occurs in Galicia, Leon, and Asturias. Although hundreds of Iberian wolves are illegally killed annually, the population has expanded south across the river Duero and east to the Asturias and Pyrenees Mountains.
In 1978, wolves began recolonising central Sweden after a 12-year absence, and have since expanded into southern Norway. As of 2020, the total number of Swedish and Norwegian wolves is estimated to be 450. The gray wolf is protected in Sweden but with a 12% annual rate of poaching, and partially controlled in Norway. The Scandinavian wolf populations owe their continued existence to neighbouring Finland's contiguity with the Republic of Karelia, which houses a large population of wolves. Wolves in Finland are protected only in the southern third of the country, and can be hunted in other areas during specific seasons, though poaching remains common, with 90% of young wolf deaths being due to human predation, and the number of wolves killed exceeds the number of hunting licenses, in some areas by a factor of two. Furthermore, the decline in the moose populations has reduced the wolf's food supply. Since 2011, the Netherlands, Belgium and Denmark have also reported wolf sightings presumably by natural migration from adjacent countries. In 2016, a female wolf tracked 550 kilometers from a region southwest of Berlin to settle in Jutland, Denmark where male wolves had been reported in 2012 for the first time in 200 years. Wolves have also commenced breeding in Lower Austria's Waldviertel region for the first time in over 130 years.
Wolf populations in Poland have increased to about 800–900 individuals since being classified as a game species in 1976. Poland plays a fundamental role in providing routes of expansion into neighbouring Central European countries. In the east, its range overlaps with populations in Lithuania, Belarus, Ukraine, and Slovakia. A population in western Poland expanded into eastern Germany and in 2000 the first pups were born on German territory. In 2012, an estimated 14 wolf packs were living in Germany (mostly in the east and north) and a pack with pups has been sighted within 15 miles of Berlin; the number increased to 46 packs in 2016. The gray wolf is protected in Slovakia, though an exception is made for wolves killing livestock. A few Slovakian wolves disperse into the Czech Republic, where they are afforded full protection. Wolves in Slovakia, Ukraine and Croatia may disperse into Hungary, where the lack of cover hinders the buildup of an autonomous population. Although wolves have special status in Hungary, they may be hunted with a year-round permit if they cause problems.
Romania has a large population of wolves, numbering 2,500 animals. The wolf has been a protected animal in Romania since 1996, although the law is not enforced. The number of wolves in Albania and North Macedonia is largely unknown, despite the importance the two countries have in linking wolf populations from Greece to those of Bosnia and Herzegovina and Croatia. Although protected, sometimes wolves are still illegally killed in Greece, and their future is uncertain. Wolf numbers have declined in Bosnia and Herzegovina since 1986, while the species is fully protected in neighbouring Croatia and Slovenia.
Although wolf-dog hybridization in Europe has raised concern among conservation groups fearing for the gray wolf's purity, genetic tests show that introgression of dog genes into European gray wolf populations does not pose a significant threat. Also, as wolf and dog mating seasons do not fully coincide, the likelihood of wild wolves and dogs mating and producing surviving offspring is small.
Asia
Historical range and decline
During the 19th century, gray wolves were widespread in many parts of the Holy Land east and west of the Jordan River. However, they decreased considerably in number between 1964 and 1980, largely because of persecution by farmers. The species was not considered common in northern and central Saudi Arabia during the 19th century, with most early publications citing sources which involved animals either from southwestern Asir, northern rocky areas bordering Jordan, or areas surrounding Riyadh.
The gray wolf's range in the Soviet Union encompassed nearly the entire territory of the country, being absent only on the Solovetsky Islands, Franz-Josef Land, Severnaya Zemlya, and the Karagin, Commander and Shantar Islands. The species was extirpated twice in Crimea, once after the Russian Civil War, and again after World War II. Following the two world wars the Soviet wolf populations peaked twice, with 30,000 wolves being harvested annually out of a population of 200,000 during the 1940s, and 40,000–50,000 harvested during peak years. Soviet wolf populations reached a low around 1970, disappearing over much of European Russia. The population increased again by 1980 to about 75,000, with 32,000 being killed in 1979. Wolf populations in northern Inner Mongolia declined during the 1940s, primarily because of poaching of gazelles, the wolf's main prey. In British-ruled India, wolves were heavily persecuted because of their attacks on sheep, goats and children. In 1876, 2,825 wolves were bountied in the North-Western Provinces (NWP) and Bihar. By the 1920s, wolf eradication remained a priority in the NWP and Awadh. Overall, over 100,000 wolves were killed for bounties in British India between 1871 and 1916.
Wolves in Japan were extirpated during the Meiji restoration period, in a campaign known as ōkami no kujo. The wolf was deemed a threat to ranching, which the Meiji government promoted at the time, and targeted via a bounty system and a direct chemical poisoning campaign inspired by the similar contemporary American campaign. The last Japanese wolf was a male killed on January 23, 1905 near Washikaguchi (now called Higashi Yoshiro). The now-extirpated Japanese wolves were descended from large Siberian wolves, which colonized the Korean Peninsula and Japan, before it separated from mainland Asia, 20,000 years ago during the Pleistocene. During the Holocene, the Tsugaru Strait widened and isolated Honshu from Hokkaido, thus causing climatic changes leading to the extinction of most large-bodied ungulates inhabiting the archipelago. Japanese wolves likely underwent a process of island dwarfism 7,000–13,000 years ago in response to these climatological and ecological pressures. C. l. hattai (formerly native to Hokkaidō) was significantly larger than its southern cousin C. l. hodophilax, as it inhabited higher elevations and had access to larger prey, as well as a continuing genetic interaction with dispersing wolves from Siberia.
Gray wolves had a wide historic range in China encompassing nearly all of mainland China, including southern China. A systematic review by Wang et al. in 2016, found museum specimens from wolves from across China, in 13 provinces, including several in southern China - two specimens sampled from two southern Chinese provinces (Zhejiang and Fujian) in 1974, and one from southern Yunnan in 1985. This study also reviewed more than 100 articles and found modern, recent records of gray wolves in every continental province of China between 1964 and the present except for three provinces - Tianjin, Jiangsu, and Fujian. Wolves were recorded in South China (in Yunnan province) as late as 2011, and in the two southernmost provinces (Guangdong and Guangxi) in the year of 2000. From these findings, the researchers concluded that wolves are still present across all parts of continental China.
Modern range
There is little reliable data on the status of wolves in the Middle East, save for those in Israel and Saudi Arabia, though their numbers appear to be stable, and are likely to remain so. Throughout the Middle East, the species is only protected in Israel. Israel has a stable population of 80-100 Indian wolves and 100-150 Arabian wolves, which are legally protected under the 1955 Wildlife Protection Law. Elsewhere, it can be hunted year-round by Bedouins. Israel's conservation policies and effective law enforcement maintain a moderately sized wolf population, which radiates into neighbouring countries, while Saudi Arabia has vast tracts of desert, where about 300–600 wolves live undisturbed. The wolf survives throughout most of its historical range in Saudi Arabia, probably because of a lack of pastoralism and abundant human waste. Turkey may play an important role in maintaining wolves in the region, because of its contiguity with Central Asia. Although Turkish wolves have no legal protection, they may number about 7,000 individuals. The mountains of Turkey have served as a refuge for the few wolves remaining in Syria. A small wolf population occurs in the Golan Heights, and is well protected by the military activities there. Wolves living in the southern Negev desert are contiguous with populations living in the Egyptian Sinai and Jordan.
The northern regions of Afghanistan and Pakistan are important strongholds for the wolf. It has been estimated that there are about 300 wolves in approximately of Jammu and Kashmir in northern India, and 50 more in Himachal Pradesh. Overall, India supports about 800–3,000 wolves, scattered among several remnant populations. Although protected since 1972, Indian wolves are classed as endangered, with many populations lingering in low numbers or living in areas increasingly used by humans. Little is known of current wolf populations in Iran, which occurred throughout the country in low densities during the mid-1970s. Although present in Nepal and Bhutan, there is no information on wolves occurring there.
Wolf populations throughout Northern and Central Asia are largely unknown, but are estimated in the hundreds of thousands based on annual harvests. Since the fall of the Soviet Union, continent-wide culling of wolves has ceased, and wolf populations have increased to about 25,000–30,000 animals throughout the former Soviet Union. In China and Mongolia, wolves are only protected in reserves. Mongolian populations have been estimated at 10,000–30,000, while the status of wolves in China is more fragmentary. The north has a declining population of an estimated 400 wolves, while Xinjiang and Tibet hold about 10,000 and 2,000 respectively. In 2008, an authoritative reference stated that the gray wolf could be found across mainland China.
In 2017, a comprehensive study found that the gray wolf was present across all of mainland China, both in the past and today. It exists in southern China, which refutes claims made by some researchers in the Western world that the wolf had never existed in southern China. In 2019, a genomic study on the wolves of China included museum specimens of wolves from southern China that were collected between 1963 and 1988. The wolves in the study formed 3 clades: north Asian wolves that included those from northern China and eastern Russia, Himalayan wolves from the Tibetan Plateau, and a unique population from southern China. One specimen from Zhejiang province in eastern China shared gene flow with the wolves from southern China, however its genome was 12-14 percent admixed with a canid that may be the dhole or an unknown canid that predates the genetic divergence of the dhole. The wolf population from southern China is believed to be still existing in that region. On Hainan Island, historical records of gray wolves exist until 1931, where they are estimated to have become extinct around 1941.
North America
Historical range and decline
Originally, the gray wolf occupied all of North America north of about 20°N. It occurred all over the mainland, except for the southeastern United States and the tropical and subtropical areas of Mexico. Large continental islands occupied by wolves included Newfoundland, Vancouver Island, the southeastern Alaskan islands, and throughout the Arctic Archipelago and Greenland. While Lohr and Ballard postulated that the gray wolf had never been present on Prince Edward Island, analysis of references to the island's native fauna in unpublished and published historical records has found that gray wolves were resident there at the time of the first French settlement in 1720. In his November 6, 1721 letter to the French Minister of the Marine, Louis Denys de La Ronde reported that the island was home to wolves "of a prodigious size", and sent a wolf pelt back to France to substantiate his claim. As the island was cleared for settlement, the gray wolf population may have been extirpated, or relocated to the mainland across the winter ice: the few subsequent wolf reports date from the mid-19th century and describe the creatures as transient visitors from across the Northumberland Strait.
The decline of North American wolf populations coincided with increasing human populations and the expansion of agriculture. In Canada, the gray wolf was extirpated in New Brunswick and Nova Scotia between 1870 and 1921, and in Newfoundland around 1911. It vanished from the southern regions of Quebec and Ontario between 1850 and 1900. The gray wolf's decline in the prairies began with the extirpation of the American bison and other ungulates in the 1860s–70s. From 1900 to 1930, the gray wolf was virtually eliminated from the western U.S. and adjoining parts of Canada, because of intensive predator control programs aimed at eradicating the species. By the start of the 20th century, the species had almost disappeared from the eastern U.S., excepting some areas of the Appalachians and the northwestern Great Lakes Region. The gray wolf was extirpated by federal and state governments from all of the U.S. by 1960, except in Alaska and northern Minnesota. The decline in North American wolf populations was reversed from the 1930s to the early 1950s, particularly in southwestern Canada, because of expanding ungulate populations resulting from improved regulation of big game hunting. This increase triggered a resumption of wolf control in western and northern Canada. Thousands of wolves were killed from the early 1950s to the early 1960s, mostly by poisoning. This campaign was halted and wolf populations increased again by the mid-1970s.
Modern range
The gray wolf is found in approximately 80% of its historical range in Canada, thus making it an important stronghold for the species. Canada is home to about 52,000–60,000 wolves, whose legal status varies according to province and territory. First Nations residents may hunt wolves without restriction, and some provinces require licenses for residents to hunt wolves while others do not. In Alberta, wolves on private land may be baited and hunted by the landowner without requiring a license, and in some areas, wolf hunting bounty programs exist. Large-scale wolf population control through poisoning, trapping and aerial hunting is also presently conducted by government-mandated programs in order to support populations of endangered prey species such as woodland caribou.
In Alaska, the gray wolf population is estimated at 6,000–7,000, and can be legally harvested during hunting and trapping seasons, with bag limits and other restrictions. In 1978, wolves were protected in the United States under the federal Endangered Species Act as it was determined that they were in danger of going extinct and needed protection to aid their recovery. Canadian wolves began to naturally recolonize northern Montana around Glacier National Park in 1979, and the first wolf den in the western U.S. in over half a century was documented there in 1986. The wolf population in northwest Montana initially grew as a result of natural reproduction and dispersal to about 48 wolves by the end of 1994. From 1995 to 1996, wolves from Alberta and British Columbia were reintroduced into Yellowstone National Park and Idaho and expanded their range into the northern Rocky Mountains and Pacific Northwest. Wolves began swimming the Snake River from Idaho to Oregon in the 1990s. The vast majority clustered in their historic range in the northeast corner of the state, where the forests are full of elk and deer. In 2010, state biologists noticed wolves dispersing into the Cascade Range. Washington state officials observed wolves from Idaho, Montana, Oregon, and British Columbia dispersing into eastern Washington and the North Cascades. The California Department of Fish and Wildlife (CDFW) monitored the expansion of wolves in Oregon and began in 2011 to prepare for the possibility of wolves recolonizing the state. The repopulation of wolves in California was recognized in late December 2011, when OR-7, a male wolf from Oregon, became the first confirmed wild wolf in California since 1924. The first resident wolf pack was confirmed in 2015. Additional wolves have been tracked entering the state, as the Cascade Range extends south from Oregon into northern California. Wolves are dispersing into the Sierra Nevada and other portions of their historic habitat.
Wolves from the Greater Yellowstone Ecosystem have dispersed into Colorado several times in the 21st century. In 2021, scientists documented the first litter of pups born to wolves in the state since the wolves' original extirpation. This resident wolf pack is monitored by Colorado Parks & Wildlife. In 2020, voters narrowly approved wolf reintroduction into the state. In December of 2023, ten wolves were released on public lands in Colorado's Summit and Grand Counties.
Occasionally, Eastern wolves (Canis lycaon) from Canada disperse into Upstate New York. This has been officially confirmed three times in the 21st century. The most recent wolf to enter New York was killed by a hunter who mistook it for a coyote.
The Western Great Lakes forests are inhabited by wolves which includes the provinces of Manitoba and Ontario along with the Midwestern states of Michigan, Minnesota, and Wisconsin which are estimated to have 4,400 wolves. Management under the Endangered Species Act allowed the wolves in Minnesota to flourish and repopulate northern Wisconsin and the Upper Peninsula of Michigan. Wolves were removed from federal protection in January 2021 with management authority remaining with state and tribal authorities. This was reversed except in Idaho, Montana, Wyoming, and parts of nearby states by a court order on February 10, 2022.
The Mexican wolf (Canis lupus baileyi) was reintroduced to Arizona, New Mexico, and the Sierra Madre Occidental in Mexico in 1998. Reintroduced Mexican wolves in Arizona and New Mexico are protected under the ESA and, as of late 2002, number 28 individuals in eight packs. On March 9, 2022, two new breeding pairs of Mexican gray wolves were released into the wild in the state of Chihuahua in northern Mexico, bringing the total number of Mexican gray wolves in the country to around 45 wild individuals. in March 2024, the Fish and Wildlife Services discovered that the wild population of Mexican gray wolves in the American Southwest had increased to 257 wolves, with 144 wolves (36 packs) in New Mexico and 113 wolves (20 packs) in Arizona. The annual pup survival rate was 62%. 113 wolves (44% of the population) have collars for monitoring and management.
In 1991, Kentucky's Land Between the Lakes partnered with the U.S. Fish and Wildlife Service for the Red Wolf Recovery Program, a captive breeding program.
See also
List of gray wolf populations by country
References
Bibliography
Animal migration
Biogeography
Population ecology
Population genetics
Wolves | Wolf distribution | [
"Biology"
] | 5,220 | [
"Ethology",
"Biogeography",
"Animal migration",
"Behavior"
] |
61,302,173 | https://en.wikipedia.org/wiki/Brazilian%20Mathematical%20Society%20Award | The Brazilian Mathematical Society Award is the highest award for mathematical expository writing. It consists of a prize of R$20,000 and a certificate, and is awarded biennial by the Brazilian Mathematical Society in recognition of an outstanding expository article on a mathematical topic.
Winners
See also
List of mathematics awards
External links
Brazilian Mathematical Society Award .
Regulations Governing the Brazilian Mathematical Society Award.
References
Mathematics awards
Awards established in 2013
Brazilian Mathematical Society | Brazilian Mathematical Society Award | [
"Technology"
] | 88 | [
"Science and technology awards",
"Science award stubs",
"Mathematics awards"
] |
61,302,860 | https://en.wikipedia.org/wiki/Aladdin%20%28hotel%20and%20casino%29 | The Aladdin was a hotel and casino located on the Las Vegas Strip in Paradise, Nevada. Toy manufacturer Edwin S. Lowe originally opened the 450-room Tallyho Hotel on the property in 1962. The Tallyho was the only major hotel in Nevada to not include a casino; it closed at the end of the year and was sold to Kings Crown Inns of America, a hotel chain which reopened the property a month later as the King's Crown Tallyho. The company added a casino and showroom but plans to open the casino were halted when the Nevada Gaming Control Board declined to issue a gambling license because of concerns about the resort being inadequately financed.
Milton Prell purchased the hotel and began an extensive $3 million renovation of the property before reopening it as the Aladdin on April 1, 1966. A 19-story hotel tower was added in 1976. After various ownership changes, the Aladdin was closed in 1997 and demolished the following year to make room for a new Aladdin resort that opened in 2000.
History
Tallyho (1962–1963)
The English Tudor-styled Tallyho hotel was conceived by owner Edwin S. Lowe, a New York toy manufacturer who also served as the president of the hotel. Lowe, who believed that there were some Las Vegas tourists who were not interested in gambling, chose not to add a casino to the Tallyho. The hotel was built on the Las Vegas Strip, across the street from the Dunes resort. Construction of the Tallyho was underway in March 1962, with an opening planned for July. In May 1962, the Clark County Ground Water Board denied an application for a water well that would be used for a nine-hole pitch and putt golf course, which Lowe planned to construct at the rear of the property. A nine-hole golf course was ultimately added to the final plans.
In June 1962, the hotel's opening was delayed until October 1, 1962. Simultaneously, county officials discovered that the three-story stucco hotel may be in violation of fire codes. A request was made for the owner to propose plans to fireproof the hotel's wooden roof and attic. County officials suggested the installation of either a sprinkler system or sheet rock in the attic, as well as the addition of fire-proof materials on the roof of the hotel structures. In November 1962, key positions in the resort were being named while an opening date of Christmas week was being planned.
The Tallyho Hotel and Country Club opened on December 24, 1962, at a cost of $12 million. Grand opening celebrations were held in February 1963. It was the only major resort in Nevada to not include a casino. The hotel featured 450 rooms, 32 villas, six restaurants, horseback and bicycle-riding facilities, and a helicopter service to take guests to nearby attractions such as Mount Charleston and Lake Mead. Despite the lack of a casino, the business was operating successfully at the time of its opening. However, the Tallyho closed on October 10, 1963, because of low revenue caused by the lack of a casino. The closure affected 100 employees, and Lowe conceded that it was a mistake to not open the hotel with an adjoining casino.
King's Crown Tallyho (1963–1966)
Kings Crown Inns of America, Incorporated, a chain of hotels, purchased the Tallyho at a cost of $7 million, and reopened it as the King's Crown Tallyho on November 5, 1963. Kings Crown planned to add a casino and showroom as soon as possible. The Tallyho was Kings Crown's first hotel in the western United States.
Lighting and sound system details for the showroom were being finalized in March 1964, while Kings Crown planned to have the showroom opened in the summer. Sound men who designed the showroom consulted with sound engineers at the University of California, Los Angeles. Film producer Steve Parker, husband of actress Shirley MacLaine, was named as the head of the hotel's showroom, to be named the Crown Room Theater-Restaurant. In addition, Parker was named as a part owner in the resort. In April 1964, a fire started in one of the hotel rooms and caused smoke damage to part of the hotel. The fire was believed to have been started by a cigarette.
Groundbreaking ceremonies for the casino and showroom were scheduled for the weekend of April 11–12, 1964. Celebrities, including MacLaine, were expected to attend the ceremonies. Other additions in the $3 million expansion project would include a convention hall and another restaurant. Future plans included the addition of a 15-story hotel structure with 500 rooms. Construction of the casino and showroom was underway in May 1964, while Parker was planning a show that would feature non-topless showgirls, a concept that was not present in other showgirl shows in Las Vegas.
By the end of 1964, a partnership of six corporations, with a total of 17 stockholders, was seeking a gambling license to open the casino as part of a $500,000 investment. On December 22, 1964, the Nevada Gaming Control Board deferred action on the approval of a gambling license until the following month to allow time for an investigation of the partnership's finances. A New Year's Eve opening date had been planned for the casino, while the possibility remained for a showroom lounge and two new restaurants to open at that time, although they ultimately did not. A total of 500 people were expected to be employed at the resort's new facilities. In January 1965, the Gaming Board considered the request for a gambling license, but agreed to the hotel's request to delay action for another 30 days so financial agreements could be worked out between people in the partnership. By that time, the partnership consisted of 18 people with a total investment of $800,000.
In February 1965, as the Gaming Board was considering the issuance of a gambling license, the hotel submitted multiple partnership changes that would include increasing Parker's ownership from eight percent to twenty percent. The Gaming Board deferred action on the gambling license until the following month. Board member W. E. Leypoldt said, "I don't think it's fair to ask us to act on something that's entirely different from what was presented Monday. It would do the casino industry a great deal of harm if you opened and in six months went broke because of lack of financing."
The request for a gambling license was withdrawn in March 1965, to allow more time to reorganize the partnership. Later that month, a suit was filed by Kings Crown Tallyho Inn Incorporated, Equitable Real Estate Investment Trust, and Fidelity Real Estate Investment Trust, all of which requested that the present leasees of the hotel be removed for not paying $632,000 in rent and other payments. The companies stated that other groups were interested in taking over the resort as soon as the leasees, including Chuck Luftig and Edward Nealis, could be removed.
Phone service to the hotel was cut off in April 1965, due to unpaid phone bills dating back to January. All 50 non-permanent guests were asked to leave the hotel. Luftig and Nealis were removed as lessees at the end of the month, after a judge ruled that the hotel be vacated and returned to Kings Crown. The next month, Luftig and Nealis asked for a $3.3 million judgment, alleging that Kings Crown failed to finish necessary improvements to the property during the period of August 1964 to January 1965, leading to financial losses.
Aladdin (1966–1998)
On January 1, 1966, Milton Prell agreed to purchase the King's Crown Tallyho, which was owned by three trusts overseen by the Cook brothers of Indiana. Prell agreed to purchase the resort for $10 million, which would be delivered in monthly payments.
Prell announced plans to remove the old English theme and reopen the resort as the Oriental-themed Aladdin on April 16 following an extensive $3 million renovation. Prell also planned to construct a $20 million, 40-story hotel addition with 600 rooms. Construction of the high-rise was expected to begin later in the year. Martin Stern Jr. was the architect for the Aladdin project, while R. C. Johnson and Associates was the contractor and was hired to construct new facilities and renovate existing structures. Renovation plans included the remodeling of the showroom and lounge, as well as the casino and the hotel's front side. Elevators and escalators were also installed at the hotel's two main front entrances. The original English-themed room wings were kept, but received an Arabian Nights theme along with the rest of the resort. The Aladdin was named after the character of the same name. A serrated canopy was added along with a $750,000, 15-foot "Aladdin's Lamp" sign.
Two weeks after Prell took over the property, a new opening date of April 1 was announced due to the fast progress of renovations, while construction of the high-rise was expected to begin in the fall. Later in the month, Prell requested a gambling license to operate 27 table games and 350 slot machines, with casino operations to be financed at a cost of $400,000 through Prell and his partners, Gil Gilbert and Sidney Krystal. Prell owned a 20-percent interest in the hotel corporation, while Gilberts, the corporate vice president, held five percent and Krystal, secretary-treasurer, had seven percent. A large group of investors owned the remaining stock. Prell named Joe Rollo and Bernie Richards, both of Beverly Hills, to serve as entertainment director and head of orchestrations respectively. The Gaming Board recommended approval of Prell's request for a gambling license in February 1966. Prell was approved the next month for gaming and liquor licenses, with approval to operate 351 slot machines and 29 table games.
Opening and ownership changes
The resort opened as Milton Prell's Aladdin at midnight on April 1, 1966, becoming the first major resort to open on the Las Vegas Strip in nine years. The Aladdin included the largest casino on the Las Vegas Strip and the 500-seat Bagdad Theatre. People present at the grand opening included Prell and his wife, as well as County Commission Chairman William H. Briare, Las Vegas mayor Oran K. Gragson, and Las Vegas Sun publisher Hank Greenspun. The Aladdin, located on , included a golf course and five dining facilities. A week after opening, the sign for the Dunes casino welcomed the Aladdin and wished the new resort "good luck." The Aladdin was considered one of the most luxurious resorts on the Las Vegas Strip, although profits were usually low. Construction of the high-rise hotel addition was scheduled to begin in October 1966.
In September 1966, nine people – including Prell's daughter Sheila – were approved to invest $287,500 for a combined 11.5 percent interest in the Aladdin. At the end of 1966, Prell stopped making payments to the trusts, stating he could not afford the overall $10 million sale price. The trusts agreed to reduce the sale price to $5 million, and Prell's purchase of the property was completed on February 9, 1967. Prell Hotel Corporation was the new owner.
In May 1967, the Aladdin was host to Elvis and Priscilla Presley's wedding.
In 1968, MK Investment Corporation made a failed offer to purchase the Aladdin. Renovations totaling $750,000 were completed in August 1969, which included making the Sinbad Lounge enclosed and leveled above the casino floor with Arabic motif.
In 1969, Parvin Dohrmann Corporation took over the Aladdin, and the company was renamed as Recrion Corporation. In February 1971, a group led by Las Vegas resident Walter Gardner agreed to purchase the Aladdin at a cost of $16.5 million. The sale was to be completed once the new owners received licensing to operate the Aladdin's casino. Recrion's agreement with Gardner required that the sale be completed by May 15, 1971. Gardner was a former executive at the Binion's Horseshoe in downtown Las Vegas, and his group included six unnamed investors. In May 1971, Recrion granted the group an extension in order to raise the money to complete the purchase. The deal was cancelled later in the month after Gardner failed to make the purchase, which resulted in Recrion filing a $250,000 suit against Gardner.
By the end of 1971, Recrion was planning a $5 million sale of the Aladdin, which would help pay off the resort's debts. The Aladdin was sold to Sam Diamond, St. Louis politicians Peter Webbe and Sorkis Webbe, and St. Louis attorney Richard L. Daly for $5 million. The new owners announced plans for the $25 million, 24-story, 800-room Regency Tower, to be built adjacent to the Aladdin and expected to be opened in late 1973. Under the new owners, a $60 million face lift was conducted, including the addition of a 17-story tower and the new 7,500-seat Performing Arts Center replacing the golf course, which was $4 million over budget.
Construction began on the 19-story "Tower of Majesty" in May 1975. It was designed by Lee Linton, and built by the Del E. Webb Corporation. The tower opened on June 1, 1976.
A $250,000 porte-cochere continued the tower's arabesques. The Aladdin added a new $300,000 blockbuster sign with little neon, huge attraction panels and none of the arabesque of the Aladdin's original sign. The Aladdin celebrated the grand opening of their new "Aladdin Theatre for the Performing Arts" with singer Neil Diamond being paid $650,000 for four shows; July 2 through July 5, 1976. In 1981, heavy metal band Iron Maiden played at the Aladdin – it was their first-ever concert in America.
In August 1979, several individuals were convicted by a Detroit Federal Jury of conspiring to allow hidden owners to exert control over the resort, and the Nevada Gaming Commission then closed the hotel.
The resort was sold to Wayne Newton and Ed Torres in 1980 for $85 million, snubbing an offer from comedian Johnny Carson. Newton sold his share to Torres 21 months later. Newton sued NBC, who had alleged in broadcasts, that his purchase of the Aladdin was tied to the mafia. He won a $22.8 million judgement, which was overturned on appeal. In February 1984, the Aladdin went into Chapter 11 bankruptcy.
In 1986, Japanese businessman Ginji Yasuda purchased the Aladdin out of bankruptcy for $54 million. Yasuda spent an additional $35 million to refurbish the resort. Yasuda was removed as the casino's operator by state regulators in September 1988. Yasuda placed the resort in Chapter 11 bankruptcy in October 1989, and died two months later. The property was publicly put up for sale in 1990, after months of unsuccessful private attempts to locate a buyer.
The New Jersey–based Bell Atlantic-Tricon Leasing Corporation acquired the resort out of bankruptcy from Ginji Corporation in 1991. That year, Bell Atlantic-Tricon put the property up for sale at a minimum price of $44 million. In January 1994, businessman Donald Trump considered purchasing the Aladdin for $51 million, although Bell Atlantic-Tricon declined to sell the property for less than $60 million. Trump decided not to purchase the Aladdin as he felt the price was too high. Interest in the property increased following the news of Trump's potential purchase, with several prospective buyers emerging. At the time, the resort consisted of a 1,000-room hotel and a 37,000 square-foot casino. Later in 1994, Jack Sommer, a Las Vegas real estate developer, and the Sommer Family Trust purchased the hotel. The Sommer Family Trust owned the Aladdin through Aladdin Gaming Corporation – which also operated the resort – and Aladdin Holdings LLC. A pair of endangered peregrine falcons nested on the hotel tower during the mid-1990s.
In May 1996, plans were approved by the Clark County Commission for a $600 million renovation and expansion of the Aladdin, which had 1,100 hotel rooms at the time. Sommer and the county spent six months working on the design of the project, which would retain the original hotel tower and theater. The expansion would include four new hotel towers, including a centerpiece 400-foot-high rectangular tower. Other additions would include a 256-room timeshare condominium, a 300-room hotel-casino, and a shopping mall that would be co-managed by Eddie DeBartolo. The hotel would continue operations during the expansion project, which was expected to take 24 to 30 months. On December 6, 1996, American psychedelic rock band Phish performed at the Aladdin, marking the first appearance in Las Vegas by the band. The performance was ultimately released as a CD/DVD release entitled Vegas 96. The concert featured a guest appearance by members of the band Primus and a group of Elvis impersonators.
In January 1997, Aladdin Gaming Corporation announced that London Clubs International would invest $50 million for a 25 percent interest in the Aladdin resort. London Clubs planned to add a luxury gaming facility to the Aladdin, aimed at attracting high rollers. The new facility would include 30 gaming tables and 100 slot machines. It would be part of the two-year renovation and expansion project, which was expected to cost $750 million and was scheduled to begin later in 1997. The new gaming facility would feature a European design. The Aladdin had been struggling to compete against larger resorts on the Las Vegas Strip.
In March 1997, Aladdin Holdings announced that the resort would add a shopping mall as part of the expansion project. It would feature the Aladdin's Arabian theme and was expected to open in 1999, with TrizecHahn Corporation handling construction, leasing, and operations. The mall, to be known as Desert Passage, was expected to cost $210 million. For the expansion project, Jack Sommer considered various options, which included closing the resort to renovate it, and demolishing the resort entirely to build a new one.
Closure and demolition
On September 25, 1997, it was announced that the Aladdin would close in two months and eventually be demolished to make room for a new Aladdin resort that would be three times larger than the original, and would include the Desert Passage mall. The Aladdin had 1,485 employees, while the new resort would employ over 7,000 people. The Aladdin's 7,000-seat Theater for the Performing Arts would be retained and modernized for the new resort. Among the final performances in the Aladdin theater was Jane's Addiction.
The Aladdin closed at 6:00 p.m. on November 25, 1997. Few casino guests expressed sadness about the closure. The Aladdin theater hosted its final performance later that night, with a show by Mötley Crüe. The performance turned chaotic when the band encouraged the audience to stand up, as one person tried to grab the hat worn by guitarist Mick Mars, accidentally knocking him down. Demolition was expected to begin in December 1997, and an implosion of the hotel tower was expected to occur in February 1998. The Aladdin's porte cochere contained 9,230 light bulbs, which cost a total of $23,499 to light up during 1997. In February 1998, Aladdin Gaming announced that it had financed plans for the new Aladdin resort, expected to cost $826 million. National Content Liquidators conducted an on-site liquidation sale of the Aladdin beginning on March 6, 1998.
On April 27, 1998, the hotel tower was imploded at 7:27 p.m. to make way for construction of the new Aladdin resort. It was the fifth Las Vegas resort to be imploded. The tower was imploded by Controlled Demolition, Inc., who had handled every hotel implosion on the Strip to this point. According to company president Mark Loizeaux, the tower used a poor concrete block design. He said, "This is the worst construction I've ever seen. It's shoddy. It's a poor man's high-rise. It is extremely susceptible to collapse. It is not a building I'd want to be in in an earthquake". The design meant that bringing down the tower in the implosion would be easy, but it also posed a challenge for getting the building to come down in the right direction. Because the tower would be easy to bring down during the implosion, Loizeaux decreased the amount of explosives from 370 pounds to 232 pounds.
An estimated 20,000 people arrived to watch the implosion from nearby. Aladdin executives set up a 1,000-person tent near the Aladdin and charged $250 a ticket for people to watch the implosion from inside the tent, with the proceeds benefiting the Make-A-Wish Foundation of Southern Nevada. The old resort's sign read, "Out of the dust Aladdin rises anew. See you in 2000." Frank Wright, the curator of the Nevada State Museum, said about the Aladdin's lack of success: "I don't know why it never made it. It never had the glamour of the Sands or the exotic dancers of the Tropicana or the Dunes or Stardust. Maybe it was location, but the Hacienda was farther out, and it was a success." Don Payne, the former chief of the Las Vegas News Bureau, said the Aladdin "certainly couldn't match the Flamingo or the Dunes. It never had the big name entertainment policy. It didn't have the advertising the big guys had. But it was a well-thought-of place."
New resort (since 2000)
The new Aladdin resort opened in August 2000. It experienced financial problems and entered Chapter 11 bankruptcy protection in September 2001. In February 2002, Aladdin Gaming was searching for potential buyers. The resort was sold in bankruptcy on June 20, 2003 to a partnership of Planet Hollywood and Starwood. After a renovation, the resort began operating in 2007 under the name "Planet Hollywood".
Film history
Robert Hirsch, a Las Vegas location consultant and the former director of the Nevada Motion Picture Division, said that film and television crews "always loved the porte cochere" of the Aladdin, but that they "just didn't like the rest of the place." The Aladdin's casino was featured substantially in the 1979 film Going in Style and the 1986 film Heat. The porte cochere and casino appeared in the 1993 film, Best of the Best II, while the theatre appeared in the 1997 documentary film, Dancing for Dollars. Behind Closed Doors, a documentary series, shot footage of the hotel tower's demolition preparations prior to its implosion. The series also placed cameras inside the tower to give an interior view of the building during the implosion. The Aladdin was also featured in a 1998 episode of Ohh Nooo! Mr. Bill Presents, in which the character of Mr. Bill performs at the resort. Footage of the implosion was used in Gambling, Gods and LSD (2002), in the closing credits of the 2003 film The Cooler and in the 2021 film The Misfits.
See also
List of casinos in Nevada
References
1962 establishments in Nevada
Casino hotels
Casinos in the Las Vegas Valley
Companies that have filed for Chapter 11 bankruptcy
Companies that filed for Chapter 11 bankruptcy in 1984
Companies that filed for Chapter 11 bankruptcy in 1989
Defunct casinos in the Las Vegas Valley
Defunct hotels in the Las Vegas Valley
Demolished hotels in Clark County, Nevada
1997 disestablishments in Nevada
Buildings and structures demolished in 1998
Las Vegas Strip
Resorts in the Las Vegas Valley
Buildings and structures demolished by controlled implosion | Aladdin (hotel and casino) | [
"Engineering"
] | 4,902 | [
"Buildings and structures demolished by controlled implosion",
"Architecture"
] |
61,303,090 | https://en.wikipedia.org/wiki/Evelyn%20Brower%20Man | Evelyn Brower Man (October 7, 1904 – September 3, 1992) was an American biochemist. She was a leading woman in developing the first test to detect hormone levels in the thyroid gland.
Early life and education
Evelyn B. Man was born in Lawrence, New York, but she grew up in North Stonington, Connecticut. Man's father, Edward Man, was an attorney from New York City and her mother was Mary Hewitt Man.
Man graduated from Wheeler High School, and then, in 1925, she graduated from Wellesley College with a degree in chemistry. Man graduated from Yale with a doctorate degree in physiological chemistry in 1932.
Career
From 1928 to 1961, Man worked as a researcher, and technician, and then a professor at Yale. She worked at a lab at Yale with John P. Peters and Herman Yannet where they developed the first test to detect hormone levels in the thyroid gland. The test was called Butanol-Extractable Iodine (BEI) test. In 1961, Man continued her research at Brown University, where she discovered infants with low hormone levels in the thyroid gland later developed a cognitive disability as children. Man advocated for infants to get their thyroid hormone levels tested. Man also studied the effects of nuclear radiation on the thyroid gland in Japanese survivors.
In 1970, Man retired from Brown University. Throughout her career, Man published 156 scientific papers and published her last paper in 1991.
For her work, Man was awarded the American Thyroid Association's Distinguished Service Award in 1976 and the United Cerebral Palsy Award for Research.
Death
On September 3, 1992, Man died of lung cancer in her home in West Hartford, Connecticut. Man was 87 years old at the time of her death.
References
1904 births
1992 deaths
Yale Faculty of Arts and Sciences
Biochemists
Wellesley College alumni
Yale University alumni | Evelyn Brower Man | [
"Chemistry",
"Biology"
] | 367 | [
"Biochemistry",
"Biochemists"
] |
61,303,201 | https://en.wikipedia.org/wiki/Virginia%20Tucker | Virginia Layden Tucker (1909 – January 19, 1985) was an American mathematician whose work at the National Advisory Committee for Aeronautics (NACA), the precursor to NASA, allowed engineers to design and improve upon airplanes. Tucker was one of the first human computers at the NACA, served as a recruiter for the program, and later worked as an aerodynamicist and an advocate for women in mathematics.
Life and career
Tucker was born in Hertford, North Carolina in 1909. She was the valedictorian of Perquimans High School's first graduating class in 1926 and is an alumna of the North Carolina College for Women where she graduated in 1930 with a B.A. in mathematics and a minor in education.
Tucker spent the next four years as a high school mathematics teacher in her hometown. In 1935, she was recruited to work at the Langley Memorial Aeronautical Laboratory (now Langley Research Center), the main research center for the National Advisory Committee for Aeronautics, at the time. Tucker was one of five women from around the country recruited to be part of Langley's first "computer pool". As human computers, these women were responsible for processing the large amounts of data gathered from flight, wind tunnel, and aeronautical tests conducted at the facility, as the NACA did not have electrical computers at the time.
As World War II began in 1939, the rapid development of aeronautical technologies became a main priority of the U.S. Military and as a result, the demand for human computers at Langley grew rapidly. Tucker traveled across the country (particularly the South) recruiting and training female mathematicians for the program.
In 1946, Tucker was promoted to the position of Overall Supervisor for Computing at Langley overseeing around 400 female "human computers", many of whom she recruited.
In 1948, Tucker left the NACA to become a researcher at the Northrop Corporation. She also became an advocate for women in engineering, working as the director of the Los Angeles Section of the Society of Women Engineers (SWE) chair of SWE's National Finance Committee from 1955 to 1956, and as SWE's representative to the Los Angeles Technical Societies Council in 1957.
Tucker left Northrop after 17 years and returned to North Carolina where she became the supervisor of a local school system until her retirement in 1974.
Virginia Tucker died on January 19, 1985, at the age of 75.
See also
Hidden Figures
Grace Hopper
Katherine Johnson
Women in computing
References
1909 births
1985 deaths
20th-century American mathematicians
Human computers
National Advisory Committee for Aeronautics
Mathematicians from North Carolina
People from Hertford, North Carolina
University of North Carolina at Greensboro alumni
20th-century American women mathematicians | Virginia Tucker | [
"Technology"
] | 533 | [
"Human computers",
"History of computing"
] |
61,304,144 | https://en.wikipedia.org/wiki/Coherent%20Raman%20scattering%20microscopy | Coherent Raman scattering (CRS) microscopy is a multi-photon microscopy technique based on Raman-active vibrational modes of molecules. The two major techniques in CRS microscopy are stimulated Raman scattering (SRS) and coherent anti-Stokes Raman scattering (CARS). SRS and CARS were theoretically predicted and experimentally realized in the 1960s. In 1982 the first CARS microscope was demonstrated. In 1999, CARS microscopy using a collinear geometry and high numerical aperture objective were developed in Xiaoliang Sunney Xie's lab at Harvard University. This advancement made the technique more compatible with modern laser scanning microscopes. Since then, CRS's popularity in biomedical research started to grow. CRS is mainly used to image lipid, protein, and other bio-molecules in live or fixed cells or tissues without labeling or staining. CRS can also be used to image samples labeled with Raman tags, which can avoid interference from other molecules and normally allows for stronger CRS signals than would normally be obtained for common biomolecules. CRS also finds application in other fields, such as material science and environmental science.
Background
Coherent Raman scattering is based on Raman scattering (or spontaneous Raman scattering). In spontaneous Raman, only one monochromatic excitation laser is used. Spontaneous Raman scattering's signal intensity grows linearly with the average power of a continuous-wave pump laser. In CRS, two lasers are used to excite specific vibrational modes of molecules to be imaged. The laser with a higher photon energy is normally called the pump laser and the laser with a lower photon energy is called Stokes laser. In order to produce a signal their photon energy differences must match the energy of a vibrational mode:
,
where the .
CRS is a nonlinear optical process, where the signal level is normally a function of the product of the powers of the pump and Stokes lasers. Therefore, most CRS microscopy experiments are performed with pulsed lasers, where higher peak power improved the signal levels of CRS significantly.
Coherent anti-Stokes Raman scattering (CARS) Microscopy
In CARS, anti-Stokes photons (higher in energy, shorter wavelength than the pump) are detected as signals.
In CARS microscopy, there are normally two ways to detect the newly generated photons. One is called forward-detected CARS, the other called epi-detected CARS. In forward-detected CARS, the generated CARS photons together with pump and Stokes lasers go through the sample. The pump and Stokes lasers are completely blocked by a high optical density (OD) notch filter. The CARS photons are then detected by a photomultiplier tube (PMT) or a CCD camera. In epi-detected CARS, back-scattered CARS photons are redirected by a dichroic mirror or polarizing beam splitter. After high OD filters are used to block back-scattered pump and Stokes lasers, the newly generated photons are detected by a PMT. The signal intensity of CARS has the following relationship with the pump and Stokes laser intensities , the number of molecules in the focus of the lasers and the third order Raman susceptibility of the molecule:
The signal-to-noise ratio (SNR), which is a more important characteristic in imaging experiments depends on the square root of the number of CARS photons generated, which is given below:
There are other non-linear optical processes that also generate photons at the anti-Stokes wavelength. Those signals are normally called non-resonant (NR) four-wave-mixing (FWM) background in CARS microscopy. These background can interfere with the CARS signal either constructively or destructively. However, the problem can be partially circumvented by subtracting the on- and off-resonance images or using mathematical methods to retrieve the background free images.
Stimulated Raman scattering (SRS) microscopy
In SRS, the intensity of the energy transfer from the pump wavelength to the Stokes laser wavelength is measured as a signal. There are two ways to measure SRS signals, one is to measure the increase of power in Stokes laser, which is called stimulated Raman gain (SRG). The other is to measure the decrease of power in the pump laser, which is called stimulated Raman loss (SRL). Since the change of power is on the order of 10−3 to 10−6 compared with the original power of pump and Stokes lasers, a modulation transfer scheme is normally employed to extract the SRS signals. The SRS signal depends on the pump and Stokes laser powers in the following way:
Shot noise limited detection can be achieved if electronic noise from detectors are reduced well below optical noise and the lasers are shot noise limited at the detection frequency (modulation frequency). In the shot noise limited case, the signal-to-noise ratio (SNR) of SRS is
The signal of SRS is free from the non-resonant background which plagues CARS microscopy, although a much smaller non-resonant background from other optical process (e.g. cross-phase modulation, multi-color multi-photon absorption) may exist.
SRS can be detected in either the forward direction and epi directions. In forward-detected SRS, the modulated laser is blocked by a high OD notch filter and the other laser is measured by a photodiode. Modulation transferred from the modulated laser to the originally unmodulated laser is normally extracted by a lock-in amplifier from the output of photodiode. In epi-detected SRS, there are normally two methods to detect the SRS signal. One method is to detect the back-scattered light in front of the objective by a photodiode with a hole at the center. The other method is similar to the epi-detected CARS microscopy, where the back-scattered light goes through the objective and is deflected to the side of the light path, normally with the combination of a polarizing beam splitter and a quarter wave-plate. The Stokes (or pump) laser is then detected after filtering out the pump (or Stokes laser).
Two-color, multi-color, and hyper-spectral CRS microscopy
One pair of laser wavelengths only gives access to a single vibrational frequency. Imaging samples at different wavenumbers can provide a more specific and quantitative chemical mapping of the sample. This can be achieved by imaging at different wavenumbers one after another. This operation always involves some type of tuning: tuning of one of the lasers' wavelengths, tuning of a spectral filtering device, or tuning of the time delay between the pump and Stokes lasers in the case of spectral-focusing CRS. Another way of performing multi-color CRS is to use one picosecond laser with a narrow spectral bandwidth (<1 nm) as pump or Stokes and the other laser with broad spectral bandwidth. In this case, the spectrum of the transmitted broadband laser can be spread by a grating and measured by an array of detectors.
Spectral-focusing CRS
CRS normally use lasers with narrow bandwidth lasers, whose bandwidth < 1 nm, to maintain good spectral resolution ~ 15 cm−1. Lasers with sub 1 nm bandwidth are picosecond lasers. In spectral-focusing CRS, femtosecond pump and Stokes lasers are equally linearly chirped into picosecond lasers. The effective bandwidth become smaller and therefore, high spectral resolution can be achieved this way with femtosecond lasers which normally have a broad bandwidth. The wavenumber tuning of spectral-focusing CRS can be achieved both by changing the center wavelength of lasers and by changing the delay between pump and Stokes lasers.
Applications
Coherent Raman histology
One of the major applications for CRS is label-free histology, which is also called coherent Raman histology, or sometimes stimulated Raman histology. In CRH, CRS images are obtained at lipid and protein images and after some image processing, an image similar to H&E staining can be obtained. Different from H&E staining, CRH can be done on live and fresh tissue and doesn't need fixation or staining.
Cell metabolism
The metabolism of small molecules like glucose, cholesterol, and drugs are studied with CRS in live cells. CRS provide a way to measure molecular distribution and quantities with relatively high throughput.
Myelin imaging
Myelin is rich in lipid. CRS is routinely used to image myelin in live or fixed tissues to study neurodegenerative diseases or other neural disorders.
Pharmaceutical research
The functions of drugs can be studied by CRS too. For example, an anti-leukemia drug imatinib are studied with SRS in leukemia cell lines. The study revealed the possible mechanism of its metabolism in cells and provided insight about ways to improve drug effectiveness.
Raman tags
Even though CRS allows label-free imaging, Raman tags can also be used to boost signal for specific targets. For example, deuterated molecules are used to shift Raman signal to a band where the interference from other molecules is absent. Specially engineered molecules containing isotopes can be used as Raman tags to achieve super-multiplexing multi-color imaging with SRS.
Comparison to confocal Raman microscopy
Confocal Raman microscopy normally uses continuous wave lasers to provide a spontaneous Raman spectrum over a broad wavenumber range for each point in an image. It takes a long time to scan the whole sample, since each pixel requires seconds for data acquisition. The whole imaging process is long and therefore, it is more suitable for samples that do not move. CRS on the other hand measures signals at single wavenumber but allows for fast scanning. If more spectral information is needed, multi-color or hyperspectral CRS can be used and the scanning speed or data quality will be compromised accordingly.
Comparison between SRS and CARS
In CRS microscopy, we can regard SRS and CARS as two aspects of the same process. CARS signal is always mixed with non-resonant four-wave mixing background and has a quadratic dependence on concentration of chemicals being imaged. SRS has much smaller background and depends linearly on the concentration of the chemical being imaged. Therefore, SRS is more suitable for quantitative imaging than CARS. On the instrument side, SRS requires modulation and demodulation (e.g. lock-in amplifier or resonant detector). For multi-channel imaging, SRS requires multichannel demodulation while CARS only needs a PMT array or a CCD. Therefore, the instrumentation required is more complicated for SRS than CARS.
On the sensitivity side, SRS and CARS normally provide similar sensitivities. Their differences are mainly due to detection methods. In CARS microscopy, PMT, APD or CCDs are used as detectors to detect photons generated in the CARS process. PMTs are most commonly used due to their large detection area and high speed. In SRS microscopy, photodiodes are normally used to measure laser beam intensities. Because of such differences, the applications of CARS and SRS are also different.
PMTs normally have relatively low quantum efficiency compared with photodiodes. This will negatively impact the SNR of CARS microscopy. PMTs also have reduced sensitivity for lasers with wavelengths longer than 650 nm. Therefore, with the commonly used laser system for CRS (Ti-sapphire laser), CARS is mainly used to image at high wavenumber region (2800–3400 cm−1). The SNR of CARS microscopy is normally poor for fingerprint imaging (400–1800 cm−1).
SRS microscopy mainly uses silicon photodiode as detectors. Si photodiodes have much higher quantum efficiency than PMTs, which is one of the reasons that the SNR of SRS can be better than CARS in many cases. Si photodiodes also suffer reduced sensitivity when the wavelength of laser is longer than 850 nm. However, the sensitivity is still relatively high and allows for imaging in fingerprint region (400–1800 cm−1).
See also
References
Microscopy
Raman spectroscopy | Coherent Raman scattering microscopy | [
"Chemistry"
] | 2,489 | [
"Microscopy"
] |
61,307,135 | https://en.wikipedia.org/wiki/IED%20Design%20Awards | The IED Design Awards consist of an awards gala organized by the Madrid headquarters of the Istituto Europeo di Design since 2016, whose purpose is to honor all those people and projects that stand out within the design world. Encompassing everything ranging from brands, professionals, entrepreneurs and to even groups, the IED presents awards every year to diverse projects and initiatives, raising awareness and promoting them, recognizing their importance and quality, and highlighting the value of design and creativity.
The awards take place on a ceremony that, since 2017, has been held in the Italian Embassy in Madrid. The finalists and winners are chosen by a committee of experts madep up of outstanding professionals from the design world and members of the management team of the different IED schools in Madrid.
The IED Design Awards include over 18 categories, encompassing the fashion world, interior design, digital design, product design, graphic design and process design, among others.
In 2018, the Honorific Award category was added, in order to pay homage to the career of an exceptional professional from the design field. In 2018, the award was granted to the publicist Toni Segarra, who is considered to be the 'best creative of the 20th Century'. At the 2019 edition, the British fashion designer, Katharine Hamnett, was awarded the honor for her outstanding career and her pioneering activism in favor of the sustainability of the fashion industry, which started over 30 years ago.
Awards
2016
The ceremony took place the 20th of May 2016 at the Aula Magna of IED Madrid, and was hosted by Patricia Conde.
2017
The ceremony took place on 15 June in the Italian Embassy in Spain, and was hosted by the actress and model Laura Sánchez. The ceremony also featured the presence of the Italian ambassador, Stefano Sannino
2018
The ceremony, held on 21 June in the gardens of the Italian Embassy in Spain, would once again feature the presence of the Italian Ambassador. The journalist and presenter Sandra Barnerda, was responsible for hosting this ceremony.
2019
The ceremony was held on 20 June in the gardens of the Italian Embassy in Spain. Sandra Barneda once again hosted the ceremony.
See also
List of fashion awards
References
Bibliography
External links
Official website
Fashion awards
Design awards | IED Design Awards | [
"Engineering"
] | 444 | [
"Design",
"Design awards"
] |
61,308,580 | https://en.wikipedia.org/wiki/Anti-structure | In crystallography, an anti-structure is obtained from a salt structure by exchanging anion and cation positions.
For instance, calcium fluoride, CaF2, crystallizes in a cubic motif called the fluorite structure. The same crystal structure is found in numerous ionic compounds with formula AB2, such as ceria (CeO2), zirconia (cubic ZrO2), uranium dioxide (UO2). In the corresponding anti-structure, called the antifluorite structure, anions and cations are swapped, such as beryllium carbide (Be2C) or lithium oxide (Li2O), potassium sulfate (K2SO4).
Other anti-structures include:
anti-SnO2: Ti2N
anti-PbCl2: Co2P
anti-CdCl2: Co2N
anti-CdI2: Cs2O
anti-NbS2: Hf2S
anti-ReO3: Cu3N
anti-LaF3: Cu3P, Cu3As
References
Crystallography | Anti-structure | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 227 | [
"Crystallography",
"Condensed matter physics",
"Materials science"
] |
69,190,374 | https://en.wikipedia.org/wiki/Mental%20illness%20denial | Mental illness denial or mental disorder denial is a form of denialism in which a person denies the existence of mental disorders. Both serious analysts and pseudoscientific movements question the existence of certain disorders.
A minority of professional researchers see disorders such as depression from a sociocultural perspective and argue that solutions should be sought through fixing a dysfunction in the society, not in the person's brain.
Insight
In psychiatry, insight is the ability of an individual to understand their mental health, and anosognosia is the lack of awareness of a mental health condition.
Certain psychological analysts argue this denialism is a coping mechanism usually fueled by narcissistic injury. According to Elyn Saks, probing patient's denial may lead to better ways to help them overcome their denial and provide insight into other issues. Major reasons for denial are narcissistic injury and denialism. In denialism, a person tries to deny psychologically uncomfortable truth and tries to rationalize it. This urge for denialism is fueled further by narcissistic injury. Narcissism gets injured when a person feels vulnerable (or weak or overwhelmed) for some reason like mental illness.
Scholarly criticism of psychiatric diagnosis
Scholars have criticized mental health diagnoses as arbitrary. According to Thomas Szasz, mental illness is a social construct. He views psychiatry as a social control and mechanism for political oppression. Szasz wrote a book on the subject in 1961, The Myth of Mental Illness.
See also
Anti-intellectualism
References
Denialism
Mental disorders | Mental illness denial | [
"Biology"
] | 308 | [
"Mental disorders",
"Behavior",
"Human behavior"
] |
69,191,109 | https://en.wikipedia.org/wiki/Interning%20%28computer%20science%29 | In computer science, interning is re-using objects of equal value on-demand instead of creating new objects. This creational pattern is frequently used for numbers and strings in different programming languages. In many object-oriented languages such as Python, even primitive types such as integer numbers are objects. To avoid the overhead of constructing a large number of integer objects, these objects get reused through interning.
For interning to work the interned objects must be immutable, since state is shared between multiple variables. String interning is a common application of interning, where many strings with identical values are needed in the same program.
History
Lisp introduced the notion of interned strings for its symbols. The LISP 1.5 Programmers Manual describes a function called intern which either evaluates to an existing symbol of the supplied name, or if none exists, creates a new symbol of that name. This idea of interned symbols persists in more recent dialects of Lisp, such as Clojure in special forms such a (def symbol) which perform symbol creation and interning.
In the object-oriented programming paradigm interning is an important mechanism in the flyweight pattern, where an interning method is called to store the intrinsic state of an object such that this can be shared among different objects which share different extrinsic state, avoiding needless duplication.
Interning continues to be an important technique for managing memory use in programming language implementations; for example, the Java Language Specification requires that identical string literals (that is, literals that contain the same sequence of code points) must refer to the same instance of class String, because string literals are "interned" so as to share unique instances. In the Python programming language small integers are interned, though the details of exactly which are dependent on language version.
Motivation
Interning saves memory and can thus improve performance and memory footprint of a program. The downside is time required to search for existing values of objects which are to be interned.
See also
Flyweight pattern
Hash consing
References
External links
Design Patterns - University of Washington
String interning in Python
A standard library package for interning in Go - The Go Blog
Software optimization
String (computer science) | Interning (computer science) | [
"Mathematics",
"Technology"
] | 445 | [
"Sequences and series",
"Computer science",
"Mathematical structures",
"String (computer science)"
] |
69,191,814 | https://en.wikipedia.org/wiki/Brenda%20Almond | Brenda Margaret Almond (; 19 September 1937 – 14 January 2023) was a British philosopher, known for her work on philosophy of education and applied ethics. She was an elected member of the Austrian Academy of Sciences.
Biography
Almond co-founded the Society for Applied Philosophy in 1982 with her then colleague at Surrey University Anthony O'Hear and co-founded the International Journal of Applied Philosophy in 1983 part of a conscious strategy of moving philosophy away from abstract and abstruse debates towards issues that affect people in their everyday lives. Almond’s writing highlights issues like health and family and social relations. In 1987, at a time when HIV/AIDS was still barely understood, she wrote in The Times on the difficult balance of health and safety over risk and freedom. “What is clear”, she wrote, “is that in the absence of a vaccine or cure, the virus will increasingly move towards the centre of the world stage”. Almond went on to write a book setting out key debates in the area called AIDS: A Moral Issue (MacMillan) in 1990. Among the topics discussed here are confidentiality, autonomy and welfare, the role of the media, legal implications of infection in Britain and the US, coping with the threat of death, along with some theological reflections.
Almond also organised and reported on academic conferences on the issue including one held at Surrey University in 1986 focussing on medical confidentiality and discrimination and the Third International Conference on AIDS in Washington in 1987.
In later years, Almond moved on to issues such as biotechnologies and even debates about who and what constituted a “legitimate target” during a war. In an opinion piece for the magazine Philosophy Now she accused fellow philosophers of still preferring to “stick to tired and familiar academic debates while the world burns”.
Almond was later a professor emeritus at Hull University.
Almond argued that ultimately the freedom to opt out of the education system altogether must be protected, as well as the freedom to choose a religious education in a secular state, or a secular education in a religious state in Education and the Individual, (written when she was in her thirties, under her married name), and went on to write Moral Concerns, The Philosophical Quest and Exploring Ethics: A Traveller's Tale and The Fragmenting Family. As part of a personal profile of Almond, the Times Higher Education Supplement says "she argues that the family is about more than stability in the present: it is about the past and the future" and notes that the book emphasises G. K. Chesterton's description of the family as "this frail cord, flung from the forgotten hills of yesterday to the invisible mountains of tomorrow".
As well as being a philosophy professor, Almond sought to present her particular view of individual rights to a wider public. She argued regularly for maintenance of the “welfare of the child provision” when legislation was crafted to reflect the changing technologies of birth and raised ethical issues surrounding the use of human embryos.
Ailsa Stevens wrote in an article that appeared in BioNews that Almond, "felt that anxieties over hybrid embryo research had been fuelled by confusion over the definition of an embryo".
Almond died in Sussex on 14 January 2023, at the age of 85. In an appreciation published by The Guardian, her son Martin Cohen noted that her "authentic voice" was to be found in her best-known title, The Philosophical Quest (1990), a mix of conventional, essentially educational, summaries of the core themes of philosophy, alongside more fluid, creative passages in which the narrator records receiving philosophical letters from a mysterious correspondent called Sophia, even as her later writing centred on defence of the "traditional family" from both social and technological changes.
Selected publications
Awards and honors
She was awarded an Honorary doctorate by the University of Utrecht in 1998. In 1999 she was named an elected member of the Austrian Academy of Sciences.
References
1937 births
2023 deaths
20th-century British philosophers
21st-century British philosophers
Alumni of University College London
British women philosophers
English philosophers
Environmental ethicists
Members of the Austrian Academy of Sciences
Academics of the University of Hull
People from Liverpool | Brenda Almond | [
"Environmental_science"
] | 829 | [
"Environmental ethicists",
"Environmental ethics"
] |
69,192,283 | https://en.wikipedia.org/wiki/Perkinsida | Perkinsida is an order of alveolates in the phylum Perkinsozoa.
References
Perkinsozoa
Alveolata orders | Perkinsida | [
"Biology"
] | 30 | [
"Eukaryotes",
"Eukaryote stubs"
] |
69,192,937 | https://en.wikipedia.org/wiki/Helena%20Edlund | Helena Edlund is a Swedish professor and molecular biologist. She received her Ph.D. from Umeå University in 1991. She is a professor in Molecular Developmental Biology at Umeå University where she researches Type 2 diabetes and β-cell function. She is one of the founders, along with Thomas Edlund and Olof Karlsson, of the biopharmaceutical company Betagenon.
In 2000, Edlund was the recipient of the Minkowski Prize given by the European Association for the Study of Diabetes (EASD) for her work in factors controlling beta-cell identity and glucose homeostasis. She is a member of the Royal Swedish Academy of Sciences. She has written numerous articles on beta cell differentiation, beta cell function, pancreatic development, and Type 2 diabetes.
References
External links
Mini CV Helana Edlund Scientific Advisory Board, Oslo University Hospital
Living people
Molecular biologists
Umeå University alumni
Diabetologists
Minkowski Prize recipients
Members of the Royal Swedish Academy of Sciences
Year of birth missing (living people) | Helena Edlund | [
"Chemistry"
] | 209 | [
"Molecular biologists",
"Biochemists",
"Molecular biology"
] |
69,193,526 | https://en.wikipedia.org/wiki/Isomorphic%20Labs | Isomorphic Labs Limited is a London-based company which uses artificial intelligence for drug discovery. Isomorphic Labs was founded by Demis Hassabis, who also serves as the CEO. The company was incorporated on February 24, 2021 and announced on November 4, 2021. It was established under Alphabet Inc. as a spin-off from its AI research lab DeepMind, of which Hassabis is also founder and CEO.
The company draws upon DeepMind's AlphaFold technology, which can be used to predict protein structures in the human body with high accuracy, allowing its researchers to find new target pathways for drug delivery.
In December 2022, Isomorphic Labs announced its second office location in Lausanne, Switzerland.
In January 2024, Isomorphic Labs partnered with Novartis AG and Eli Lilly and Company to work together on AI drug discovery and research.
In May 2024, Google DeepMind and Isomorphic Labs announced the release of AlphaFold 3, freely available on the AlphaFold server for non-commercial research. AlphaFold 3 is not limited to predicting how proteins fold, it can also predict the interactions with molecules typically found in drugs such as ligands or antibodies, which is expected to significantly accelerate drug discovery.
In November 2024, preliminary results of CASP16 showed AlphaFold 3-based models did not significantly outperform older methods for predicting protein-ligand interactions. The top performing models in the CASP16 Pose Prediction for Pharma Targets section were ClusPro and CoDock utilizing AlphaFold 2 based predictions, human visual inspection, and manual adjustments.
References
External links
Alphabet Inc.
Biotechnology companies
Drug discovery companies
Artificial intelligence companies
Companies based in London
2021 establishments in the United States | Isomorphic Labs | [
"Chemistry",
"Engineering",
"Biology"
] | 343 | [
"Biotechnology organizations",
"Drug discovery companies",
"Drug discovery",
"Biotechnology companies"
] |
69,193,536 | https://en.wikipedia.org/wiki/Markita%20del%20Carpio%20Landry | Markita del Carpio Landry is a Bolivian-American chemist who is an associate professor in the department of chemical engineering at the University of California, Berkeley. Her research considers nanomaterials for brain imaging and the development of sustainable crops. She was a recipient of the 2022 Vilcek prize for creative promise. del Carpio Landry's work has been featured on NPR, popular mechanics, the San Francisco Chronicle, and C&E News.
Early life and education
del Carpio Landry's parents are both teachers, and she has said that her early training was in curiosity-based science. Landry earned her bachelor's degrees at the University of North Carolina at Chapel Hill, where she majored in both chemistry and physics. She moved to the University of Illinois Urbana-Champaign for doctoral studies and earned a Ph.D. in chemical physics. Her research considered the development of single-molecule spectroscopies for investigating DNA polymer oxidative damage. del Carpio Landry was a National Science Foundation postdoctoral scholar at the Massachusetts Institute of Technology. She performed research at both the Technical University of Munich and Osaka University. del Carpio Landry is a fluent speaker of French, English, and Spanish.
Research and career
In July 2016, del Carpio Landry was appointed to the faculty at Berkeley, where she started to explore nanotechnology-based approaches to image neuromodulation in the brain using synthetic nanoparticle-polymer conjugates. Such materials are incredibly versatile, with tunable chemical and physical properties. They can be processed using low cost fabrication techniques, permitting the creation of biomimetic structures. She uses functionalism carbon nanotubes to detect the neurotransmitters dopamine and norepinephrine with high spatial and temporal resolution. She simultaneously develops near-infrared fluorescent probes to explore fundamental biological processes.
del Carpio Landry has also demonstrated that carbon nanotubes can be used to deliver DNA into plant cells with applications in plant genome editing. Delivering DNA to plants is complicated due to the rigid, multi-layer cell walls, yet del Carpio Landry has also demonstrated that nanoparticles can be used to deliver RNA into plants. During the COVID-19 pandemic, del Carpio Landry started to explore nanosenors for detecting the spike proteins of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and to increase the sensitivity of RT-qPCR detection of SARS-CoV-2 infections.
Awards and honors
2017 Frontiers of Engineering Symposium
2017 Chan-Zuckerberg Biohub
2018 International Union of Pure and Applied Chemistry World Leading Chemist
2018 Howard Hughes Medical Institute Gilliam Fellowship
2018 Sloan Research Fellowship
2018 Burroughs Wellcome Fund
2019 Frontiers of Science Alumni
2019 Chemical & Engineering News Talented 12
2019 Prytanean Faculty Award
2019 DARPA Young Investigator Award
2020 University of Illinois Urbana-Champaign Young Alumni Award
2020 Emerging Leader in Molecular Spectroscopy Award
2020 Cell Press 100 Most Inspiring Hispanic/Latinx Scientists in America
2021 Nature Estée Lauder Research Awards for Inspiring Women in Science
2021 National Science Foundation CAREER Award
2021 Dreyfus Foundation Teacher Scholar Award
2022 Vilcek Prize for Creative Promise in Biomedical Science
2022 Chan-Zuckerberg Biohub
Selected publications
Ouassil, N.*, Pinals, R.L.*, O’Donnell, J.T.D., Wang, J., Landry, M.P.‡ Supervised Learning Model to Predict Protein Adsorption to Nanoparticles. Science Advances (2022)
Zhang, H.*, Goh, N.S.*, Wang, J., Demirer, G.S., Butrus, S., Park, S-J, Landry, M.P.‡ Nanoparticle Cellular Internalization is Not Required for RNA Delivery to Mature Plant Leaves. Nature Nanotechnology (2021)
Demirer, G.S., Zhang, H., Goh, N.S., Chang, R., Landry, M.P.‡ Carbon nanocarriers deliver siRNA to intact plant cells for efficient gene knockdown. Science Advances (2020). 6 (26)
Jeong, S., Yang, D., Beyene, A.G., O’Donnell, J.T.D., Gest, A. M., Navarro, N., Sun, X., Landry, M.P.‡ High Throughput Evolution of Near Infrared Serotonin Nanosensors. Science Advances (2019). 5 (12), 1-12
Beyene, A. G., Delevich, K., O’Donnell, J.T.D., Piekarski, D.J., Lin, W.C., Thomas, A.W., Yang, S.J., Kosillo, P., Yang, D., Wilbrecht, L., Landry, M.P.‡ Imaging Striatal Dopamine Release Using a Non-Genetically Encoded Near-Infrared Fluorescent Catecholamine Nanosensor. Science Advances (2019). 5 (7), 1-11
Demirer, G.S., Zhang, H., Matos, J., Goh, N., Cunningham, F.J., Sung, Y., Chang, R., Aditham, A.J., , Chio, L., Cho, M.J., Staskawicz, B., Landry, M.P.‡ High Aspect Ratio Nanomaterials Enable Delivery of Functional Genetic Material Without DNA Integration in Mature Plants. Nature Nanotechnology (2019). 14, 456-464
Zhang, H.*, Demirer, G.S.*, Zhang, H., Ye, T., Goh, N.S., Aditham, A.J., Cunningham, F.J., Fan, C., Landry, M.P.‡ Low-dimensional DNA Nanostructures Coordinate Gene Silencing in Mature Plants. PNAS (2019). 116 (15), 7543-7548
References
UC Berkeley College of Chemistry faculty
American women chemists
University of North Carolina at Chapel Hill alumni
University of Illinois Urbana-Champaign alumni
National Science Foundation
Nanomaterials
American people of Bolivian descent
Year of birth missing (living people)
Living people
21st-century American women | Markita del Carpio Landry | [
"Materials_science"
] | 1,338 | [
"Nanotechnology",
"Nanomaterials"
] |
69,193,576 | https://en.wikipedia.org/wiki/Mercedes-Benz%20M150%20engine | The Mercedes-Benz M150 engine is a naturally-aspirated and supercharged, 7.7-liter, straight-8 engine, designed, developed and produced by Mercedes-Benz from 1938 to 1944.
Applications
Mercedes-Benz 770 Großer (W150)
References
Mercedes-Benz engines
Straight-eight engines
Engines by model
Gasoline engines by model | Mercedes-Benz M150 engine | [
"Technology"
] | 75 | [
"Engines",
"Engines by model"
] |
69,193,658 | https://en.wikipedia.org/wiki/Mercedes-Benz%20M07%20engine | The Mercedes-Benz M07 engine is a naturally-aspirated and supercharged, 7.7-liter, straight-8 engine, designed, developed and produced by Mercedes-Benz; between 1930 and 1938.
Applications
Mercedes-Benz 770 Großer (W07)
References
Mercedes-Benz engines
Straight-eight engines
Engines by model
Gasoline engines by model | Mercedes-Benz M07 engine | [
"Technology"
] | 77 | [
"Engines",
"Engines by model"
] |
69,193,759 | https://en.wikipedia.org/wiki/Mercedes-Benz%20M124%20engine | The Mercedes-Benz M124 engine is a prototype supercharged, 5.8-liter, straight-8 engine manufactured by Mercedes-Benz in 1939.
Applications
1939 Mercedes-Benz 580K (W129) (prototype)
References
Mercedes-Benz engines
Straight-eight engines
Engines by model
Gasoline engines by model | Mercedes-Benz M124 engine | [
"Technology"
] | 64 | [
"Engines",
"Engines by model"
] |
69,193,983 | https://en.wikipedia.org/wiki/Mercedes-Benz%20M24%20engine | The Mercedes-Benz M24 engine is a supercharged, 5.0-liter and 5.4-liter, straight-8 engine, designed, developed and produced by Mercedes-Benz; between 1934 and 1944.
Applications
Mercedes-Benz W31
Mercedes-Benz 500K
Mercedes-Benz 540K
References
Mercedes-Benz engines
Straight-eight engines
Engines by model
Gasoline engines by model | Mercedes-Benz M24 engine | [
"Technology"
] | 78 | [
"Engines",
"Engines by model"
] |
69,194,971 | https://en.wikipedia.org/wiki/Mercedes-Benz%20M22%20engine | The Mercedes-Benz M22 engine is a naturally-aspirated and supercharged, 3.8-liter and 4.0-liter, straight-8 engine, designed, developed and produced by Mercedes-Benz; between 1933 and 1934.
Applications
Mercedes-Benz 380
References
Mercedes-Benz engines
Straight-eight engines
Engines by model
Gasoline engines by model | Mercedes-Benz M22 engine | [
"Technology"
] | 73 | [
"Engines",
"Engines by model"
] |
69,195,464 | https://en.wikipedia.org/wiki/National%20Initiative%20for%20Cybersecurity%20Careers%20and%20Studies | National Initiative for Cybersecurity Careers and Studies (NICCS) is an online training initiative and portal built as per the National Initiative for Cybersecurity Education framework. This is a federal cybersecurity training subcomponent, operated and maintained by Cybersecurity and Infrastructure Security Agency.
Overview
The National Initiative for Cybersecurity Careers and Studies was created by the Cybersecurity and Infrastructure Security Agency as a hub that provides access to cybersecurity resources, such as courses and career development, to the public. Its mission is to strengthen the cybersecurity workforce and awareness of cybersecurity and cyberspace through accessible education. With over 6,000 cyber security training courses, career pathway tools, and up-to-date coverage on cybersecurity events and news, NICCS aims to empower current and future generations of cybersecurity professionals.
History
The initiative was launched by Janet Napolitano, then-Secretary of Homeland Security of Department of Homeland Security on February 21, 2013. The primary objective of the initiative is to develop and train the next generation of American cyber professional by involving academia and the private sector.
Goals and Objectives
NICCS was founded with the overarching goal of being a national resource for cybersecurity education, careers, and training. It aims to provide its nation with resources to ensure the workforce has the proper training and education in the cybersecurity field. NICCS advocates for cybersecurity awareness, training, education, career advancement, and broadening its nation’s cybersecurity professionals workforce. The initiative employs several strategies to achieve its goals, such as implementing K-12 and collegiate-level programs, disseminating scholarship information, and offering varied training courses.
NICCS values cybersecurity as a priority in the nation's development. It believes that cybersecurity is integral to the success of several organizations and businesses. NICCS aims to educate and train the nation’s workforce using rapidly developing technology in the cybersecurity field.
Federal Virtual Training Environment
NICCS hosts Federal Virtual Training Environment, a completely free online cybersecurity training system for federal and state government employees. It contains more than 800 hours of training materials on ethical hacking, and surveillance, risk management, and malware analysis.
Training Programs
The NICCS seeks to provide trained, and certified cybersecurity professionals to the nation. They have developed a college to workforce pipeline with the CyberCorps Scholarship for Service program. They have also partnered with the NSA to identify, and recognize institutions that have a robust cybersecurity program, and designate them as CAE’s, or Center of Academic Excellence. In addition, they provide support and resources to K-12 teachers, and students to help them increase their cyber education. They have also partnered with training institutions across the United States to connect individuals with bootcamps, workshops, and training for certifications. They have also endorsed certain certifications like Network+ and Security+ that are relevant to cybersecurity professionals.
Similar Programs and Initiatives
National Cybersecurity Workforce Framework: Sets a universally accepted way to describe cybersecurity work, and workers
Cybersecurity and Infrastructure Security Agency: Responsible for ensuring critical infrastructure security and resilience
National Institute of Standards and Technology: Sets technological standards to help promote cooperation and foster innovation
DoD Cyber Workforce Framework: Establishes descriptions for the type of cybersecurity work individuals based on their tasks
See also
Cybersecurity and Infrastructure Security Agency
National Cyber Security Division
National Initiative for Cybersecurity Education
References
Initiatives_in_the_United_States
Computer network security | National Initiative for Cybersecurity Careers and Studies | [
"Engineering"
] | 741 | [
"Cybersecurity engineering",
"Computer networks engineering",
"Computer network security"
] |
69,196,020 | https://en.wikipedia.org/wiki/1105%20%28number%29 | 1105 (eleven hundred [and] five, or one thousand one hundred [and] five) is the natural number following 1104 and preceding 1106.
Mathematical properties
1105 is the smallest positive integer that is a sum of two positive squares in exactly four different ways, a property that can be connected (via the sum of two squares theorem) to its factorization as the product of the three smallest prime numbers that are congruent to 1 modulo 4. It is also the smallest member of a cluster of three semiprimes (1105, 1106, 1107) with eight divisors, and the second-smallest Carmichael number, after 561, one of the first four Carmichael numbers identified by R. D. Carmichael in his 1910 paper introducing this concept.
Its binary representation 10001010001 and its base-4 representation 101101 are both palindromes, and (because the binary representation has nonzeros only in even positions and its base-4 representation uses only the digits 0 and 1) it is a member of the Moser–de Bruijn sequence of sums of distinct powers of four.
As a number of the form for 1105 is the magic constant for magic squares, and as a difference of two consecutive fourth powers it is a rhombic dodecahedral number (a type of figurate number), and a magic number for body-centered cubic crystals. These properties are closely related: the difference of two consecutive fourth powers is always a magic constant for an odd magic square whose size is the sum of the two consecutive numbers (here .
References
Integers | 1105 (number) | [
"Mathematics"
] | 329 | [
"Elementary mathematics",
"Integers",
"Mathematical objects",
"Numbers"
] |
69,197,337 | https://en.wikipedia.org/wiki/4-Phenylphenol | 4-Phenylphenol, also known as biphenyl-4-ol and 4-hydroxybiphenyl is an organic compound. It is a phenol analog of biphenyl.
Production
4-Phenylphenol can be obtained from the Suzuki coupling of phenylboronic acid with 4-iodophenol in the presence of 10% palladium on carbon and potassium carbonate.
Properties
4-Phenylphenol is a flammable, difficult to ignite, white, scaly solid with a phenol-like odor that is very slightly soluble in water.
References
4-Hydroxyphenyl compounds
Biphenyls | 4-Phenylphenol | [
"Chemistry"
] | 150 | [
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
69,197,818 | https://en.wikipedia.org/wiki/1%2C1%2C1-Tris%28diphenylphosphinomethyl%29ethane | 1,1,1-Tris(diphenylphosphinomethyl)ethane, also called Triphos, is an organophosphorus compound with the formula CH3C[CH2PPh2]3. An air-sensitive white solid, it is a tripodal ligand ("three-legged") of idealized C3v symmetry. It was originally prepared by the reaction of sodium diphenylphosphide and CH3C(CH2Cl)3:
3 Ph2PNa + CH3C(CH2Cl)3 → CH3C[CH2PPh2]3 + 3 NaCl
It forms complexes with many transition metals, usually as a tripodal ligand. Such complexes are used to analyze mechanistic aspects of homogeneous catalysts. For example, rhodium forms complexes with CH3C[CH2PPh2]3 like [(triphos)RhCl(C2H4)], [(triphos)RhH(C2H4)], and [(triphos)Rh(C2H5)(C2H4)], provide model intermediates in the catalytic cycle for hydrogenation of alkenes.
Triphos sometimes behaves as a bidentate ligand. Illustrative cases include fac-[Mn(CO)3Br(η2-triphos)] and [M(CO)4(η2-triphos)], where M is Cr, Mo, or W. Triphos serves as a tridentate-bridging ligand in an icosahedral Au13 cluster. The phosphine bridges three chlorogold(I) groups to form the tripod molecule of trichloro-1,1,1-(diphenylphosphinomethyl)ethanetrigold(I), CH3C[CH2PPh2AuCl]3.
Related ligands
Tris(aminomethyl)ethane, a tripodal triamine (CH3C(CH2NH2)3)
Bis(diphenylphosphinoethyl)phenylphosphine (PhP(C2H4PPh2)2)
Tris(2-diphenylphosphinoethyl)amine N[CH2CH2PPh2]
References
Tertiary phosphines
Phenyl compounds
Chelating agents
Tridentate ligands | 1,1,1-Tris(diphenylphosphinomethyl)ethane | [
"Chemistry"
] | 508 | [
"Chelating agents",
"Process chemicals"
] |
69,199,096 | https://en.wikipedia.org/wiki/Intrinsic%20bond%20orbitals | Intrinsic bond orbitals (IBO) are localized molecular orbitals giving exact and non-empirical representations of wave functions. They are obtained by unitary transformation and form an orthogonal set of orbitals localized on a minimal number of atoms. IBOs present an intuitive and unbiased interpretation of chemical bonding with naturally arising Lewis structures. For this reason IBOs have been successfully employed for the elucidation of molecular structures and electron flow along the intrinsic reaction coordinate (IRC).
IBOs have also found application as Wannier functions in the study of solids.
Theory
The IBO method entails molecular wave-functions calculated using self-consistent field (SCF) methods such as Kohn-Sham density functional theory (DFT) which are expressed as linear combinations of localized molecular orbitals.
In order to arrive at IBOs, intrinsic atomic orbitals (IAOs) are first calculated as representations of a molecular wave function for which each IAO can be assigned to a specific atom. This allows for a chemically intuitive orbital picture as opposed to the commonly used large and diffuse basis sets for the construction of more complex molecular wavefunctions.
IAOs are constructed from tabulated free-atom AOs of standard basis-sets under consideration of the molecular environment. This yields polarized atomic orbitals that resemble the free-atom AOs as much as possible, before orthonormalization of the polarized AOs results in the set of IAOs. IAOs are thus a minimal basis for a given molecule in which atomic contributions can be distinctly assigned. The sum of all IAOs spans exactly over the molecular orbitals which renders them an exact representation of the wavefunction. Since IAOs are associated with a specific atom, they can provide atom specific properties such as the partial charge. Compared to other charges, such as the Mulliken charge, the IAO charges are independent of the employed basis set.
IBOs are constructed as a linear combination over IAOs with the condition of minimizing the number of atoms over which the orbital charge is spread. Each IBO can thereby be divided into the contributions of the atoms as the electronic occupation of orbital on atom . The localization is performed in the spirit of the Pipek-Mezey localization scheme, maximizing a localization functional .
with or . While the choice of the exponent does not affect the resulting IBOs in most cases, the choice of localizes the orbitals in aromatic systems unlike .
The process of IBO construction is performed by unitary tranfomation of canonical MOs, which ensures that the IBOs remain an exact and physically accurate representation of the molecular wavefunction due to the invariance of Slater determinant wavefunctions towards unitary rotations.
The unitary matrix , which produces the localized IBOs upon matrix multiplication with set of occupied MOs , is thereby chosen to effectively minimize spread of IBOs over the atoms of a molecule. The product is a set of localized IBOs, closely resembling the chemically intuitive shapes of molecular orbitals, allowing for distinction of bond types, atomic contributions and polarization.
Application in structure and bonding
In his original paper introducing IBOs, Knizia showed the versatility of his method for describing not only classical bonding situations, such as the σ and π bond, but also aromatic systems and non-trivial bonds. The differentiation of σ and π bonds in acrylic acid is possible based on IBO geometries, as are the identification of the IBOs corresponding to the oxygen lone pairs. Benzene provided an example of a delocalized aromatic system to test the IBO method. Apart from the C-C and C-H σ-bonds, the six electron π-system is expressed as three delocalized IBOs. Representation of non-Lewis bonding was demonstrated on diborane B2H6, with one IBO stretching over B-H-B, corresponding to the 3-center-2-electron bond.
Transition metal compounds
IBO analysis was used to explain the stability of electron rich gold-carbene complexes, mimicking reactive intermediates in gold catalysis. While these complexes are sometimes depicted with a Au-C double bond, representing the sigma donation of the carbene and π backbonding of Au, IBO analysis points towards a minimal amount of π-backbonding with the respective orbital mainly localized on Au. The σ-donating carbene orbital is likewise strongly polarized towards C. Stabilization of the compound thus occurs through strong donation of the aromatic carbene substituents into the carbene carbon p-orbitals, outcompeting the Au-π-backdonation. IBO analysis was thus able to negate the double bond character of the gold-carbene complexes and provided deep insight into the electronic structure of Cy3P-Au-C(4-OMe-C6H4)2) (Cy = cyclohexyl).
The π-backbonding character was again evaluated for gold-vinylidene complexes, as another common type of gold catalysis intermediates. IBO analysis revealed significantly stronger π-backbonding for the gold-vinylidenes compared to the gold-carbenes. This was attributed to the geometric inability of aromatic vinylidene substituents to compete with Au for π-interactions since the respective orbitals are perpendicular to each other.
Knizia and Klein similarly employed IBO for the analysis of [Fe(CO)3NO]–. The even polarization of IBOs between Fe and N points towards a covalently bonded NO ligand. The double bond occurs via two d-p π-interactions and results in a formal Fe0 center. Confirmed by further calculations, IBO proved as a fast and straightforward method to interpret bonding in this case. Making use of the low computational cost, a Cloke-Wilson rearrangement catalyzed by [Fe(CO)3NO]– was investigated by constructing the IBOs for every stationary point along the IRC. It was found that one of the Fe-NO π bonds takes active part in catalysis by electron transfer to and from the substrate, explaining the unique catalytic activity of [Fe(CO)3NO]– compared to the isoelectronic [Fe(CO)4]2–.
Apart from the above mentioned compounds, the IBO method has been employed to investigate various other transition metal complexes, such as gold-diarylallenylidenes or diplatinum diboranyl complexes, proving as a valuable tool to gain insight into the extent and nature of bonding.
Main group compounds
IBO analysis has been employed in main group chemistry to elucidate oftentimes non-trivial electronic structure. The bonding of phosphaaluminirenes was, for example, investigated showing a 3-center-2π-electron bond of the AlCP cycle. Further application was found for confirming the distonic nature of a phosphorus containing radical cation reported by Chen et al. (see figure). While the IAO charge analysis yielded a positive charge on the chelated P, IBOs showed the localization of the unpaired electron on the other P atom, confirming the spatial separation of radical site and charge.
Another example is the elucidation of the electronic structure of the hexamethylbenzene dication. Three π bonding IBOs were found between the basal C5Me5 plane and the apical C, reminiscent of Cp* coordination complexes. The three π bonds are thereby polarized towards the apical C, which in turn coordinates to a CH3+ cation with its lone pair. IBO analysis therefore revealed the Lewis-acidic and Lewis-basic character of the apical C.
Applications of IBO for cluster compounds have included zirconium doped boron clusters. IBO analysis showed, that the unusual stability of the neutral ZrB12 cluster stems from several multicenter σ bonds. The B-B σ bonding orbitals extend to the central Zr atom, forming the mulicenter bonds. This example displays the method's aptitude to analyze cluster compounds and multicenter bonding.
Valence virtual intrinsic bond orbitals
Although IBOs typically describe occupied orbitals, the description of unoccupied orbitals can likewise be of value for interpreting chemical interactions. Valence virtual IBOs (vvIBOs) were introduced with the investigation of high valent formal Ni(IV) complexes. The bonding and antibonding manifold of the compound were described using IBOs and vvIBOs respectively. Compared to the widely used HOMO/LUMOs which are often spread over the whole molecule and can be difficult to interpret, vvIBOs allow for more direct interpretation of chemical interactions with unoccupied orbitals.
Electron flow along the IRC
In 2015, Knizia and Klein introduced the analysis of electron flow in reactions with IBO as a non-empirical and straight-forward method of evaluating curly arrow mechanisms. Since IBOs are exact representations of Kohn-Sham wavefunctions, they can provide physical conformation for curly arrows mechanisms based on first-principles. IBOs usually represent chemical bonds and lone pairs, this method allows for elucidation of bond rearrangements in terms of the elemental steps and their sequence. By calculating the root mean square deviations of the partial charge distributions compared to the initial charge distribution, IBOs taking active part in a reaction can be distinguished from those that remain unchanged along the IRC.
Knizia and Klein demonstrate the versatility of this method in their original report, first presenting a simple SN2-type self-exchange reaction of H3CCl and Cl–, followed by the migration of π bonds in a substitution reaction (SN2) and π- to σ-bond transformations in a Claisen rearrangement. Electron flow can be easily followed by observing the migration of an IBO and bond types are easily distinguished based on the geometries of the IBOs. The value of IBO analysis along the IRC especially shows for complex reactions, such as a cyclopropanation reaction with only one transition state and without intermediates, reported by Haven et al. Calculations by Knizia and Klein yielded a precise curly arrow mechanism for this reaction.
Closed-shell systems
Examples of IBO analysis along the IRC included the investigation of C-H bond activation by gold-vinylidene complexes. Through this method, it is possible to discern between concerted and stepwise reactions. The previously thought single step C-H activation reaction was in this case revealed to consist of three distinct phases: i) hydride transfer, ii) C-C bond formation and iii) sigma to pi rearrangement of the lone pair coordinated to Au.
Other reports of IBO analysis along the IRC include the elucidation and confirmation of a previously proposed mechanism for a [3,3]-sigmatropic rearrangement of a Au(I)-vinyl species or the epoxidation of alkene by peracids. For the latter, the textbook four curly arrow mechanism was found to be physically inaccurate. Instead, seven changing IBOs were found, yielding an ideal mechanism featuring seven curly arrows. The combination of IBO analysis with other computational methods, such as natural bond orbital (NBO) analysis for a Ti-catalyzed pyrrole synthesis or natural localized molecular orbital (NLMO) analysis for an intramolecular cycloaddition of a phosphaalkene to an arene has likewise led to insightful results regarding the specifics of the reaction mechanisms.
Open-shell systems
Klein and Knizia furthermore introduced the first examples of IBOs used for analysis of open-shell systems during proton-coupled electron transfer (PCET) and hydrogen atom transfer (HAT). The differentiation between pCET, a separate but concerted electron and proton transfer, and HAT, the transfer of a hydrogen atom, were shown for two well-studied model systems of enzymatic Fe-oxo active sites. IBOs along the IRC were calculated for the alpha and beta spin manifold respectively. While the IBO of the alpha spin electron travelled together with the proton to take part in the formation of a new H-O bond in case of HAT, the electron was transferred to the Fe-center separated from the transferred proton for PCET. The successful application of the IBO method for these two examples of open-shell systems was suggested to pave the way for broader applications to similar problems.
See also
Localized molecular orbitals
References
Electronic structure methods | Intrinsic bond orbitals | [
"Physics",
"Chemistry"
] | 2,587 | [
"Quantum chemistry",
"Quantum mechanics",
"Computational physics",
"Electronic structure methods",
"Computational chemistry"
] |
69,200,574 | https://en.wikipedia.org/wiki/HIPRA | HIPRA is a biotech pharmaceutical company headquartered in Amer, Catalonia, Spain focused on prevention for animal and human health, with a product base of vaccines and diagnostic services.
HIPRA has an international presence in 40 countries with its own subsidiaries, 3 R&D centres and production plants located in Europe (Spain) and America (Brazil).
In addition, its international distribution network maintains open distribution channels with more than 100 countries, covering all 5 continents.
Since 2020, the company has been developing a vaccine against COVID-19.
History
HIPRA got founded in 1971, in a small laboratory in Madrid. The name HIPRA comes from the surnames of its former creators: Hidalgo and Prada.
In 1991 HIPRA had a workforce of 100 people and a turnover of 10 million euros, it was an important year in HIPRA's history, with a new management team, and a redefined company expansion policy.
In the year 2000, the company began internationalization, beginning the implementation of its own subsidiaries around the world. Currently HIPRA has commercial subsidiaries in 40 countries. It also has 3 research centers and 6 production plants located in Europe and America.
In 2009 HIPRA began to focus on prevention; therefore, it stopped investing in pharmacological products.
In 2021 the new Human Health division was created by HIPRA to create new products. The same year, GoodGut was acquired by HIPRA, a biotechnological start-up dedicated to the research and development of diagnostic tests for digestive diseases.
Animal health
HIPRA has developed more than 100 vaccines for different animal species, both production and companion animals, against a wide variety of biological targets. In addition to its Amer plant, the company has another plant in Brazil, in the Porto Alegre conurbation. It also has a university research centre in the United States.
HIPRA's animal health products include vaccines, vaccination devices, integrated traceability services and diagnostic kits.
External links
hipra.com , company website
References
Biotechnology companies of Spain
Pharmaceutical companies of Spain
Vaccination-related organizations | HIPRA | [
"Biology"
] | 421 | [
"Vaccination-related organizations",
"Vaccination"
] |
69,201,249 | https://en.wikipedia.org/wiki/Mercedes-Benz%20M19%20engine | The Mercedes-Benz M19 engine is a naturally-aspirated, 3.8-liter, straight-8 engine, designed, developed and produced by Mercedes-Benz; between 1932 and 1933.
Applications
Mercedes-Benz 380 S (W10)
Mercedes-Benz 380 S (W19)
References
Mercedes-Benz engines
Straight-eight engines
Engines by model
Gasoline engines by model | Mercedes-Benz M19 engine | [
"Technology"
] | 78 | [
"Engines",
"Engines by model"
] |
69,201,422 | https://en.wikipedia.org/wiki/Mercedes-Benz%20M08%20engine | The Mercedes-Benz M08 engine is a naturally-aspirated and supercharged, 4.6-liter and 5.0-liter, straight-8 engine, designed, developed and produced by Mercedes-Benz; between 1928 and 1940.
Overview
Typ Nürburg 460 engine (1928–1929)
The engine was a 4,622cc straight-8 side-valve unit for which maximum output was given as at 3,400 rpm
Typ Nürburg 460 engine (1929–1932)
For 1929, the company's first eight-cylinder model was extensively reworked by the newly appointed Technical Director Hans Nibel. The 8-cylinder engine and most other technical details were carried over unchanged from the 1928 car including the ratios chosen for the four-speed manual transmission.
Typ Nürburg 500 engine (1931–1933)
In 1931, the car became available with an enlarged 4,918cc engine which now also featured a twin downdraft carburettor. Maximum output was now listed as at 3,100 rpm and claimed top speed increased to 110 km/h (69 mph).
Typ 500 engine (1932–1936)
In 1932 the W08 lost the “Nürburg” name, being sold simply as the Mercedes-Benz Typ 500. The 4,918cc side-valve engine with its twin downdraft carburetor was unchanged, as were the four-speed optional overdrive transmission, wheelbase, and list of standard body types.
Typ 500 engine (1936–1939)
1936 saw an increase in claimed maximum output from the engine to at 3,300 rpm. The cylinder capacity at 4,918cc was unchanged, but there was a marginal raising of the compression ratio. The claimed top speed was now raised further to 123 km/h (76 mph). The model was discontinued in 1939 without any immediate successor. Twenty-four years passed before the next 8-cylinder engined Mercedes-Benz appeared; with the Mercedes-Benz 600, in 1963.
Applications
Mercedes-Benz Nürburg 460 (W08)
References
Mercedes-Benz engines
Straight-eight engines
Engines by model
Gasoline engines by model | Mercedes-Benz M08 engine | [
"Technology"
] | 438 | [
"Engines",
"Engines by model"
] |
69,201,841 | https://en.wikipedia.org/wiki/Natural%20resonance%20theory | In computational chemistry, natural resonance theory (NRT) is an iterative, variational functional embedded into the natural bond orbital (NBO) program, commonly run in Gaussian, GAMESS, ORCA, Ampac and other software packages. NRT was developed in 1997 by Frank A. Weinhold and Eric D. Glendening, chemistry professors at University of Wisconsin-Madison and Indiana State University, respectively. Given a list of NBOs for an idealized natural Lewis structure, the NRT functional creates a list of Lewis resonance structures and calculates the resonance weights of each contributing resonance structure. Structural and chemical properties, such as bond order, valency, and bond polarity, may be calculated from resonance weights. Specifically, bond orders may be divided into their covalent and ionic contributions, while valency is the sum of bond orders of a given atom. This aims to provide quantitative results that agree with qualitative notions of chemical resonance. In contrast to the "wavefunction resonance theory" (i.e., the superposition of wavefunctions), NRT uses the density matrix resonance theory, performing a superposition of density matrices to realize resonance. NRT has applications in ab initio calculations, including calculating the bond orders of intra- and intermolecular interactions and the resonance weights of radical isomers.
History
During the 1930s, Professor Linus Pauling and postdoctoral researcher George Wheland applied quantum-mechanical formalism to calculate the resonance energy of organic molecules. To do this, they estimated the structure and properties of molecules described by more than one Lewis structure as a linear combination of all Lewis structures:
where aiκ and Ψaκ denote the weight and single-electron eigenfunction from the wavefunction for a Lewis structure κ, respectively. Their formalism assumes that localized valence bond wavefunctions are mutually orthogonal.
While this assumption ensures that the sum of the weights of the resonance structures describing the molecule is one, it creates difficulties in computing aiκ. The Pauling-Wheland formalism also assumes that cross-terms from density matrix multiplication may be neglected. This facilitates the averaging of chemical properties, but, like the first assumption, is not true for actual wavefunctions. Additionally, in the case of polar bonding, these assumptions necessitate the generation of ionic resonance structures that often overlap with covalent structures. In other words, superfluous resonance structures are calculated for polar molecules. Overall, the Pauling-Wheland formulation of resonance theory was unsuitable for quantitative purposes. Glendening and Weinhold sought to create a new formalism, within their ab initio NBO program, that would provide an accurate quantitative measure of resonance theory, matching chemical intuition. To do this, instead of evaluating a linear combination of wavefunctions, they express a linear combination of density operators, Γ, (i.e., matrices) for localized structures, where the sum of all weights, ωα, is one.
where and
In the context of NBO, the true density operator Γ represents the NBOs of an idealized natural Lewis structure. Once NRT has generated a set of density operators, Γα, for localized resonance structures, α, a least-squares variational functional is employed to quantify the resonance weights of each structure. It does this by measuring the variational error, δw, of the linear combination of resonance structures to the true density operator Γ.
To evaluate a single resonance structure, δref, the absolute difference between a single term expansion and the true density operator, approximated as the leading reference structure, can be taken. Now, the extent to which each reference structure represents the true structure may be evaluated as the "fractional improvement", fw.
From this equation, it is evident that as fw approaches one and δw approaches zero, δref becomes a better representation of the true structure.
Updates
In 2019, Glendening, Wright and Weinhold introduced a quadratic programming (QP) strategy for variational minimization in NRT. This new feature is integrated into NBO 7.0 version of their program. In this program, the matrix root-mean square deviation (Frobenius norm) of the resonance weights is calculated.
The mean-squared density matrices, representing deviation from the true density matrix, may be rewritten as a Gram matrix, and an iterative algorithm is used to minimize the Gram matrix and solve the QP.
Theory
Generation of resonance structures and their density matrices
From a given wavefunction, Ψ, a list of optimal NBOs for a Lewis-type wavefunction are generated along with a list of non-Lewis NBOs (e.g., incorporating some antibonding interactions). When these latter orbitals have nonzero value, there is "delocalization" (i.e., deviation from the ideal Lewis-type wavefunction). From this, NRT generates a "delocalization list" from deviation from the parent structure and describes a series of alternative structures reflecting the delocalization. A threshold for the number of generated resonance structures can be set by controlling the desired energetic maximum (NRTTHR threshold). The NBOs for a resonance structure formula can then be, subsequently, calculated from the CHOOSE option. Operationally, there are three ways in which alternative resonance structures may be generated: (1) from the LEWIS option, considering the Wiberg bond indices; (2) from the delocalization list; (3) specified by the user.
Below is an example of how NRT may generate a list of resonance structures.
(1) Given an input wavefunction, NRT creates a list of reference Lewis structures. The LEWIS option tests each structure and rejects those that do not conform to the Lewis bonding theory (i.e., those that do not fulfill the octet rule, pose unreasonable formal charges, etc.).
(2) The PARENT and CHOOSE operations determine the optimal set of NBOs corresponding to a specific resonance structure. Additionally, CHOOSE is able to eliminate identical resonance structures.
(3) A user may then call SELECT to select the structure that best matches to the true molecular structure. This option may also show other structures within a defined energy threshold NRTTHR, deviating from optimal Lewis density.
(4) Two other operations, CONDNS and KEKULE, are ran to remove redundant ionic structures and append structures related by bond shifts, respectively.
(5) Lastly, SECRES is called to calculate the NBOs and density matrices of each resonance structure.
Generation of resonance weights
To compute the variational error, δw, NRT offers the following optimization methods: the steepest descent algorithms BFGS and POWELL and a "simulated annealing method" ANNEAL and MULTI. Most commonly, the NRT program computes an initial guess of the resonance weights by the following relation:
where the weight is proportional to the exponential of the non-Lewis density, ρ, of structure α. Then the BFGS and POWELL steepest descent methods optimize for the nearest local minimum in energy.
In contrast, the ANNEAL option finds the global maximum of the fractional improvement, fw, and performs a controlled, iterative random walk across the fw surface. This method is more computationally expensive than the BFGS and POWELL steepest descent methods.
After optimization, SUPPL evaluates the weight of each resonance structure and modifies the list of resonance structures by either retaining or adding resonance structures of high weight and deleting or excluding those of low weight. It continues this process until either convergence is achieved or oscillation occurs.
Updates
In NBO version 7.0, the $NRTSTR function does not need to be called to generate a list of representative resonance structures, and the $CHOOSE algorithm has been adapted to be "essentially identical to the NLS [natural Lewis structure] algorithm", increasing the overall optimization of each resonance structure by reducing the amount to which the parent Lewis structure contributes to the resonance structure.
Applications
Main group chemistry
Bond order of the pnictogen bond
In 2015, Liu et al., conducted ab initio MP2/aug-cc-pvDZ calculations and used NRT in NBO version 5.0 to determine the natural bond order (i.e., a measure of electron density) of noncovalent weak "pnicogen bond" interactions—analogous to the hydrogen bond—between various compounds. Their results are summarized in the following table.
These results indicate that the ionic bond order of the O· · · P pnictogen bond is the greatest contribution to the total bond order. Therefore, this weak, noncovalent interaction is primarily electrostatic.
Bond order of Ge2M compounds
In 2018 Minh et al., used NRT in the NBO 5.G program, with density obtained from the B3P86/6-311+G(d) level of theory, to calculate the bond orders in a series of Ge2M compounds, where M is a first-row transition metal. The results are found in the following table.
These results show that the Ge–Ge bond order ranges from 1.5 to 2.4, while the Ge–M bond order ranges from 0.3 to 1.7. Furthermore, the Ge–Ge bond is primarily covalent, whereas the Ge–M bond usually has an equal mix of covalent and ionic nature. Exceptions to this are Cr, Mn, and Cu, where the ionic component is dominant because of smaller overlap with the 4s orbital of the M atom, leading to less stability. Interactions with M = Cr, Mn, and Cu are described as an electron transfer from the 4s atomic orbital on the M atom to a pi molecular orbital of the Ge2 fragment. Interactions with the other M atoms are described by two electron transfers: firstly, an electron transfer from the Ge2 fragment into an empty 3d atomic orbital on M and secondly, an electron transfer from the 3d atomic orbital on M into an antibonding orbital on Ge2.
Resonance structures and bond order of regium bonds
In 2019, Zheng et al., used NRT at the wB97XD level in the GENBO 6.0W program to generate natural Lewis resonance structures and calculate the bond orders of regium bond interactions between phosphonates and metal halides MX (M = Cu, Ag, Au; X = F, Cl, Br). In a regium bond interaction, electron donors participate in a charge transfer to the metal species. Results of this analysis are shown in the following figures and tables.
In the case of H3PO:· · · MX complexes, these results indicate that ωI is “the best natural Lewis structure” and the lone pair of electrons on the oxygen atom interact with a MX sigma antibonding orbital.
Zheng et al., also analyzed MX interactions with trans- and cis-phosphinuous acid to compare the electron donating abilities of phosphorus and oxygen atoms. The results above demonstrate that when phosphorus acts as the electron donor the weights of ωI and ωII are similar. This is indicative of 3-center 4-electron bonding models. Despite greater mixing, ωII is determined to be the best natural Lewis structure for both the trans- and cis- complexes, with CuBr and AgBr as the only exceptions. Researchers explain that this result is consistent with analyses showing the preference for phosphorus to form covalent interactions. Overall, "the degree of covalency for P–M bonds decreases in the order of F> Cl > Br, Au > Cu > Ag, while the degree of noncovalent for O–M bonds, there is an increase according to F < Cl < Br, Au < Cu < Ag in the entire family."
Weight of resonance structures of arsenic radicals
In 2015, Viana et al., used NRT to determine the weight of resonance structures of the arsenic radical isomers of AsCO, AsSiO and AsGeO, which are of interest in the fields of astrochemistry and astrobiology. The results are shown in the following figures and table.
According to Viana et al., “for most of the isomers, the percentage weight of the secondary resonance structure is negligible. In cyclic structures, the resonance weights lead to very similar percentage values.”
Limitations
Calculating chemical and physical properties by using linear combinations of density matrices, rather than wavefunctions, may result in negative, and therefore erroneous, resonance weights because it is mathematically impossible to expand the density matrix without introducing negative values.
See also
Natural bond orbital
Chirgwin-Coulson Weights
References
External links
Frank Weinhold
https://www2.chem.wisc.edu/users/weinhold
https://scholar.google.com/citations?user=47IzzwYAAAAJ&hl=en
Eric D. Glending
https://www.indstate.edu/cas/chem_phys/eric-d-glendening
https://scholar.google.com/citations?user=iRjJ1Y0AAAAJ&hl=en
Natural Bond Orbital 7.0 Homepage
https://nbo7.chem.wisc.edu/
Quantum chemistry
Computational chemistry | Natural resonance theory | [
"Physics",
"Chemistry"
] | 2,739 | [
"Quantum chemistry",
"Quantum mechanics",
"Theoretical chemistry",
"Computational chemistry",
" molecular",
"Atomic",
" and optical physics"
] |
77,958,629 | https://en.wikipedia.org/wiki/NGC%206605 | NGC 6605 is an open cluster located in the constellation Serpens. It was discovered by the British astronomer John Herschel in 1826.
Description
With a visual magnitude of 6.0, this cluster is visible to the naked eye from a very dark location free of light pollution. Elsewhere, however, the cluster can be observed with small binoculars.
NGC 6605 is located approximately 3.1 degrees southwest of Gamma Scuti, a magnitude 4.67 star in the constellation Scutum.
The apparent size of the cluster is 29 arc minutes, which, given the distance of 1144 pc and through simple calculation, equates to an actual size of about 31 light years.
See also
Pleiades
References
Open clusters
6605
Serpens | NGC 6605 | [
"Astronomy"
] | 151 | [
"Constellations",
"Serpens"
] |
77,958,790 | https://en.wikipedia.org/wiki/1%2C2-Cyclobutanedione | 1,2-Cyclobutanedione is an organic compound with the formula . It is one of two isomers of cyclobutanedione, the other being 1,3-cyclobutanedione. It is prone to polymerization. It is prepared by desilylation of 1,2-bis(trimethylsiloxy)cyclobutene.
Related compounds
Moniliformin, a naturally occurring derivative of 1,2-butanedione
References
Cyclobutanes
Enols
Diketones | 1,2-Cyclobutanedione | [
"Chemistry"
] | 117 | [
"Enols",
"Functional groups"
] |
77,959,269 | https://en.wikipedia.org/wiki/WISE%20J2354%2B0240 | WISE J2354+0240 (WISE J235402.77+024015.0, WISE 2354+0240) is a brown dwarf or free-floating planetary-mass object. It is a Y-dwarf, meaning it is one of the coldest directly imaged astronomical objects.
It was discovered in 2015, using the Wide-field Infrared Survey Explorer and spectroscopy from the Hubble Space Telescope. The authors find that the J-band peak in the spectrum is narrower than the Y0 standard and therefore assigned a spectral type of Y1, with an estimated temperature of 300−400 Kelvin. The age was estimated to be at least 1.5 billion years. Parallax measurement places this object at 7.7 parsec from the solar system.
Near-infrared photometry was later obtained with Hubble and a temperature of 335 ±11 K and a mass of 11 ±3 was estimated. WISE 2354+0240 was observed with the JWST and the temperature was estimated to be K. The object is not described in detail in this work. The authors however mention that they see a number of absorption features in their sample, including water vapor, methane, ammonia, carbon monoxide and carbon dioxide. They note that none of their objects show absorption due to phosphine, which is predicted to occur in these objects.
See also
List of Y-dwarfs
WISE J0825+2805 another Y-dwarf discovered by Schneider et al. 2015
Notes
References
Y-type brown dwarfs
Brown dwarf stubs
Astronomical objects discovered in 2015
WISE objects
Rogue planets
Pisces (constellation) | WISE J2354+0240 | [
"Astronomy"
] | 330 | [
"Pisces (constellation)",
"Constellations"
] |
77,959,365 | https://en.wikipedia.org/wiki/USS%20Sumter%20Three | In late August and early September 1972, a series of incidents on board the USS Sumter (LST-1181) off the coast of Vietnam resulted in three Black marines being charged with three counts of mutiny and eleven counts of assault, with the possibility of execution. This was "the first time since the US Civil War that American sailors or Marines had been charged with mutiny at sea".
The event that led to the arrests was a song played over the ship's radio station. Private First Class (PFC) Alexander Jenkins Jr., a 19-year-old Black marine in his role as the ship's DJ, decided to play a song by a Black artist that was popular among Black Americans at the time. The normal shipboard radio fare, which broadcast to the hundreds of sailors and marines on board, had up to this time been mainly popular white artists. As Jenkins recalled years later, "playing 'White Man’s Got a God Complex' by The Last Poets really set the white guys off." During the following days, an increasing number of disagreements and fistfights broke out between white and Black sailors and marines on board, with "some started by whites, others by Blacks."
Three Black marines were singled out as the "ringleaders", transported by helicopter to a military base in Da Nang and charged with mutiny, as well as assault, riot, and resisting arrest. The charges were so extreme that one GI underground newspaper called it an "outrageous" case of "racist prosecution". They were then transferred to Okinawa, where they spent months in the brig with the military prosecutor "pushing for 65 years of prison" after being ordered by the Marine Corps to drop the mutiny charges as clearly excessive. With the help of civilian lawyers and the prospect of charges of racism being aired during the trial, the military eventually backed down and settled for less than fully honorable discharges for the three. Three white marines also initially faced charges ranging from dereliction of duty to disorderly conductnowhere near as serious as mutiny or assault. However, they were acquitted or received no punishment. The events were characterized by The New York Times as "about race but also about structural racism."
Background
The late 1960s and early 1970s were a contentious time for race relations in the U.S. Military as the civil rights and Black liberation movements found expression within the armed forces. Especially Black troops were responding to discrimination and racism in various ways. In 1971, a Congressional Black Caucus investigation concluded, "Racism has become institutionalized at all levels of the military...Black and other minority servicemen are victims of discrimination from the time that they enter the services until the time that they are discharged." The Caucus also reported that "sixty-four percent" of Black sailors and "seventy-three percent" of Black marines felt their branch of the military to be "a poor place for Blacks to be". All of this combined with growing antiwar sentiment within the military, reflecting similar sentiments in U.S. society and worldwide. The U.S. ground war in Southeast Asia had essentially stalemated with Army grunts increasingly refusing to fight or resisting the war in various other ways. By 1972, the U.S. military was forced to shift from ground operations and turn increasingly to air bombardment. This meant that a large part of U.S. combat operations was now concentrated in the Navy's Seventh Fleet and launched from its aircraft carriers in the Gulf of Tonkin.
Also in 1972, several unprecedented developments on board U.S. Navy ships dramatically exposed the intersection of antiwar sentiment, civil rights issues, discontent over working and safety conditions, and racism. By late that year approximately 12 percent “of new Navy recruits were black” and they were often "thrust into the dreariest, most menial, and most unpopular jobs on board" In October, "racial unrest triggered the worst shipboard riot in U.S. Navy history" on board the giant aircraft carrier, the USS Kitty Hawk. When arrests were made, all 25 of those arrested were Black. A Black Navy official observed, "Anytime you have a so-called race riot and you lock up 25 blacks, that has to raise some questions." As word spread in the fleet about the incidents on board the Kitty Hawk, many of the Black sailors on the USS Constellation were “swearing an affinity with their beleaguered brothers on the Kitty Hawk.” They formed a group called the “Black Fraction,” and attempted to negotiate with the ship's captain, but were told that "six of them would be given immediate less-than-honorable discharges” and 250 men would be administratively discharged. Over 100 sailors responded with a sit-in, forcing the captain to return the ship to shore. Once docked, 144 crew members left the ship, including 8 whites. The Constellation returned to sea but returned a few days later to pick up the mutinous sailors. Most of the men, however, refused to board and “staged a defiant dockside strike - perhaps the largest act of mass defiance in naval history.” During this same month, another riot occurred on board the oiler USS Hassayampa at the Subic Bay Naval Base in the Philippines. Again, of the 11 crewmen arrested, all were Black.
While the incidents aboard the USS Sumter took place the month before these other incidents, they had similar precipitating causes.
Mutiny at sea
These were the opening words of a song played by the Black marine DJ, PFC Jenkins, to the hundreds of men aboard the USS Sumter in late August 1972. The Black GIs onboard hadn't complained about the usual fare of white artists on the ship's radio, but for many of the white GIs, especially the white Marine sergeants and officers, this song and its lyrics were a problem. "The spoken word song centered on drugs, poverty, white supremacy, and the killings of Blacks and Native Americans." Jenkins quickly found himself in "a small room" being "questioned by a group of higher-ranking white Marines" and being accused of "playing music that would incite a riot." A white Marine captain got so incensed he "jumped out of his chair so forcefully that it flipped over." The tension and animosity were just beginning.
Over the following days, several fistfights broke out with increasing frequency between Black and white GIs"some started by whites, other by Blacks." Meanwhile, Jenkins was ordered to stop playing The Last Poets, an order which so upset the 65 Black marines on board that 64 of them sent an informal complaint to the commanding Marine officer on the ship. The marines insisted that "they were being denied the right to play their own music", and requested a meeting with their battalion commander. The request was denied, "further inflaming" the tensions on board. In response, some of the Black marines were heard humming The Last Poets''' tune as they carried out their shipboard duties. According to the Omega Press, a GI underground newspaper based out of Okinawa, Japan, "Whites, armed with pipes and wrenches, roamed the ship at times looking for blacks." One of the Black marines onboard who wasn't charged told The New York Times, "We were nonviolent until they came after us and said they didn’t like our music. Then there were riots." During one of the fights between Black and white marines on September 8, a Marine officer reported being hit by Jenkins as he attempted to separate the fighters. Jenkins didn't remember hitting him, but he was accused nonetheless. Soon, Jenkins, PFC Roy L. Barnwell, and Lance CPL James S. Blackwell found themselves "singled out as leaders" and charged with mutiny, assault, riot and resisting arrest. These were the "most severe" charges brought against any of the GIs involved in any of the incidents and rebellions which were discussed above, as well as the most severe brought against any marines since the Civil War.
Hearing and trials
Once the Sumter Three arrived in Okinawa, they were able to obtain civilian lawyers, which significantly changed the dynamics of the case. The attorneys were able to mount a strong defense, including documenting some of the discrimination and racism experienced by the Black marines on board the ship. For example, the Black marine's daily routine often included "verbal attacks from white sergeants and officers", mess cooks serving them "cold and inedible food", unannounced uniform and bunk inspections, harassment and punishment for petty infractions, and more. One Black marine was confined to the brig for three days on bread and water for a minor uniform infraction, another had a "wrench thrown at him," while another was "attacked with a knife". None of these incidents were ever "investigated by the Marine leadership."
When the official Article 32 hearing commenced (the military's version of a preliminary hearing), the marines' civilian lawyers were able to quickly challenge and dispute the initial charges of mutiny as it was clear nothing like mutiny had taken place. However, the military soon added additional charges, including "riot and criminal slander". The slander charges were lodged against Blackwell for calling his marine commander a racist. Jenkins was scheduled for "a special court-martial on charges of disrespecting an officer and resisting arrest", while Barnwell and Blackwell were facing "general courts-martial for numerous counts of assault and resisting arrest." The military offered the three marines a deal to avoid court-martial by accepting undesirable discharges, but the marines refused. Blackwell told the press that he, Jenkins, and Blackwell were willing "to give up 10 years of our life to stop this". "[A]ll we want to do is just expose the marine corps of its racism, show how black and other third world GIs are constantly being railroaded into court and then given bad discharges and time."
During a lengthy five-week pre-trial hearing, many of the remaining additional charges were shown to be groundless, with even the investigating officer recommending that may be dropped or changed. In the end all charges were dropped on Barnwell and Blackwell, and they received honorable discharges for the "good of the service". Jenkins received a three-month sentence for two minor offenses after a special court-martial and was given "a general discharge under honorable conditions".
Conclusion
In the book American Defense Reform: Lessons from Failure and Success in Navy History, two military experts looked at the incidents on board the Sumter, the Kitty Hawk, the Constellation, and the Hassayampa, and called them "just the tip of an iceberg of unrest." During four months in 1972, they cataloged 98 race-related criminal cases, and they reported that "the Navy was suffering from an epidemic of sabotage by sailors disgruntled with social or racial conditions that were threatening the readiness of the entire fleet."
The events on board the Sumter and the military's prosecution of the Sumter Three were some of the earlier events during this period and the racial underpinnings could not be ignored. Even the chief of naval operations, Elmo Zumwalt, was critical of what he called the "lily-white racist Navy". Historically, "racial bias" has often played a role in the military's decisions about who to prosecute for racial unrest. A 1972 Department of Defense study reported that Black GIs "received a higher proportion of general and undesirable discharges than whites of similar aptitude and education." As recently as 2015 a study by Protect Our Defenders, a "legal justice group", found that Black service members were still "substantially more likely than white service members to face military justice or disciplinary action".
For those directly involved, the repercussions were long-lasting. According to The New York Times'', Jenkins, Barnwell, and Blackwell had difficult lives after their experiences on board the ship. As Jenkins put it, "That situation on the Sumter screwed up my whole life."
See also
Events
Fort Dix 38
Fort Hood Three
Fort Lewis Six
Intrepid Four
Presidio mutiny
General
Racism against African Americans in the U.S. military
External links
Sir! No Sir!, a film about GI resistance to the Vietnam War
A Matter of Conscience - GI Resistance During the Vietnam War
Waging Peace in Vietnam - US Soldiers and Veterans Who Opposed the War
References
United States Navy personnel of the Vietnam War
United States Navy in the Vietnam War
African-American history of the United States military
Vietnam War
United States Marine Corps
Discrimination
Civil rights and liberties
African-American United States Navy personnel | USS Sumter Three | [
"Biology"
] | 2,592 | [
"Behavior",
"Aggression",
"Discrimination"
] |
77,959,614 | https://en.wikipedia.org/wiki/Carlos%20Silva%20Acu%C3%B1a | Carlos Silva Acuña, a native of Mexico and a Canadian citizen, is a chemical physicist. He serves as a full professor in the Departments of Physics and Chemistry at the Université de Montréal and holds the Canada Excellence Research Chair in Light-Matter Interactions. He has been the Director of the Institut Courtois since July 2023. He is known for his work on ultrafast and nonlinear spectroscopy of advanced materials.
Education
Carlos Silva Acuña earned a bachelor's degree in Chemistry from Luther College in 1992. He completed a Ph.D. in Chemical Physics at the University of Minnesota in 1998, supervised by the late Professor Paul Barbara. Afterward, he conducted postdoctoral research at the Cavendish Laboratory, University of Cambridge, where he worked under the supervision of Professor Sir Richard Friend. During this period, he developed his program in ultrafast spectroscopy of materials.
Career
Carlos Silva Acuña began his career as an EPSRC Advanced Research Fellow (ARF) at the University of Cambridge and served as a Nonstipendiary Research Fellow at Darwin College, Cambridge. From 2005 to 2018, he was a professor in the Department of Physics at the Université de Montréal, where he held a Canada Research Chair in Organic Semiconductor Materials. In 2017, he took a joint appointment at the Georgia Institute of Technology, where he was a professor in the Schools of Chemistry and Biochemistry and Physics, and a courtesy professor in the School of Materials Science and Engineering.
Research
Carlos Silva Acuña is recognized for his work in nonlinear coherent optical spectroscopy of organic and hybrid semiconductor materials.
As a postdoctoral research fellow and later an EPSRC Advanced Research Fellow at the University of Cambridge he established an ultrafast spectroscopy research program in the Optoelectronics Group of the Cavendish Laboratory. His early research focused on exciton physics in conjugated polymers and and the electronic dynamics in polymer donor:acceptor blends.
In 2005, at Université de Montréal, Carlos Silva Acuña set up an ultrafast spectroscopic laboratory, focusing on the relaxation dynamics of photogenerated carriers in organic semiconductors.
In 2018, he joined Georgia Tech, where he and his team established a laboratory specializing in nonlinear ultrafast spectroscopy and quantum optics. Their work aimed at understanding the optical and electronic properties of molecular and hybrid semiconductor materials, with a focus on hybrid organic-inorganic metal-halides, quantum materials, and conjugated polymers.
In 2023, he returned to Université de Montréal as the holder of a Canada Excellence Research Chair (CERC) in Light-Matter Interactions. His research under the CERC program aims to advance the understanding of the properties of microscopic systems composed of many interacting light-induced particles in solid-state materials. This research has potential applications photonics and quantum technologies.
DEI
Carlos Silva Acuña emphasizes the importance of diversity, equity, and inclusion (DEI) in science, technology, engineering, and mathematics (STEM). He believes that scientific research and academic progress benefit from a diverse and inclusive talent pool. His research group reflects this commitment, and he is active in promoting inclusivity within the academic community.
Through his Canada Excellence Research Chair (CERC) in Light-Matter Interaction, Silva Acuña support Parité Sciences (PS), a project aimed at achieving gender parity in STEM fields. Parité Sciences provides training to Cégep and high-school STEM educators across Québec to create a more equitable environment for future scientists.
Awards and Honours
In 2005, Carlos Silva Acuña was granted a Canada Research Chair in Organic Semiconductor Materials, which was renewed in 2010. In the same year, he received the Herzberg Medal from the Canadian Association of Physicists, recognizing his contributions to physics.
In 2011, he was granted a Visiting Professorship by the Leverhulme Trust for his visit to Imperial College London. In 2014, he was appointed to the Université de Montréal Research Chair in Organic Semiconductor Materials.
In 2016, Silva Acuña received the Brockhouse Medal by the Canadian Association of Physicists for his work in condensed matter and materials physics.
In 2023, Silva Acuña was awarded the Canada Excellence Research Chair in Light-Matter Interactions and the Institut Courtois Director’s Research Chair, for his leadership in light-matter interactions research.
In 2024, Silva Acuña was named a finalist in the 16th annual TLN 10 Most Influential Hispanic Canadians.
References
Chemical physicists
Living people
1970 births | Carlos Silva Acuña | [
"Chemistry"
] | 879 | [
"Chemical physicists"
] |
77,960,589 | https://en.wikipedia.org/wiki/Ekco%20Cloud | Ekco Cloud Ltd, trading as EKCO, is an IT cloud based services provider headquartered in Dublin, Republic of Ireland. The business was founded in 2017 as Internet Corp. by Eoin Blacklock and Jonathan Crowe, before rebranding as EKCO in 2020.
History
Eoin Blacklock and Jonathan Crowe created the business in 2017, after previously setting up KeepItSafe, an IT cloud computing business. KeepItSafe was sold to US internet business J2 Global in 2010. Blacklock and Crowe stayed on at J2 Global, growing the business until they departed in 2016. When registering the business, they had planned to call the business Evil Internet Corp. as an inside joke about taking over the world referencing Austin Powers, but dropped the Evil when completing the registration. The new business was funded by €8 million brought in by IBI Corporate Finance, with a further €16 million provided by Ulster Bank. A further €8.4 million was raised by ACT Venture Capital in 2019. The finance raised was used to purchase four businesses in Netherlands, four in the United Kingdom, including Cloudhelix, and Datastring in Ireland over the first 2 and a half years of operation. By 2020, the company provided cloud services to blue chip companies such as PostNL, Heineken, Schiphol airport in Amsterdam and CPL Resources and in February of that year renamed themselves as EKCO.
In 2021, EKCO purchased CTI Global, a cloud infrastructure and IT security firm owned by Denis O'Brien. The company grew further in June 2021 by purchasing cybersecurity provider Kontex Security, which with its earlier purchases of Ward Solutions and Caveo Systems, made it the second largest Irish owned business in the cybersecurity market. This was followed up in August with the purchase of cloud services business Unity Technology Solutions, increasing EKCO's annual turnover to €103 million. In October 2022, Corten Capital, a London-based private equity firm became its majority shareholder when they purchased a stake worth €300 million.
During February 2023, EKCO, Microsoft and the National Cyber Security Centre collaborated to launch a new Secure Configuration Framework for Microsoft Office 365. EKCO continued with their purchasing spree, buying Waterford based Radius Technologies, which specialised in end-to-end IT services for small to medium-sized businesses, and iSYSTEMS, a cloud migration and cyber security services company, making EKCO one of the fastest-growing managed cloud and security services providers in Europe. The purchase was followed up in December by buying Milton Keynes based Bluecube, an IT security services company, taking their employee count to 860 and revenue to over €150 million. In the same month, Don Robert, the chair of the London Stock Exchange and a co-founder of EKCO's largest shareholder Corten Capital, became chairman of the company while EKCO became Ireland's first IT cloud provider to be awarded Microsoft Managed Service Provider achieving all four of the Microsoft security specialisations. In April 2024, EKCO continued the purchasing streak by buying CTS Group, a provider of cloud and managed IT services to law firms and barristers in Britain and Ireland that had gone into administration. The purchase had taken EKCO staff numbers to over 1000.
References
Cloud infrastructure
Cloud platforms
Companies based in Dublin (city)
Computer security companies
Irish companies established in 2017
Technology companies established in 2017 | Ekco Cloud | [
"Technology"
] | 696 | [
"Cloud infrastructure",
"Cloud platforms",
"Computing platforms",
"IT infrastructure"
] |
77,961,692 | https://en.wikipedia.org/wiki/Mucoromyceta | Mucoromyceta is a subkingdom of fungi which includes the divisions Calcarisporiellomycota, Glomeromycota, Mortierellomycota and Mucoromycota. This enormous group includes almost all molds.
Description
Molds in this group have a stalk which at the top has a caplike structure that includes the spores.
References
Further reading
Subkingdoms
Fungus taxa
Taxa described in 2018 | Mucoromyceta | [
"Biology"
] | 93 | [
"Fungus taxa",
"Fungi",
"Eukaryotes by classification",
"Fungi by classification"
] |
77,962,465 | https://en.wikipedia.org/wiki/Touch%20pool | A touch pool or touch tank is a type of aquarium attraction in public aquariums where members of the public, especially young people, are allowed to touch the wildlife within the tanks. Tanks will be stocked with species which are not dangerous to touch to provide an opportunity for individuals to learn more about those species. Tanks are good for discussion and learning opportunities for children and family, helping with ecological education and understanding of ecosystems.
Typical species in installations include Ray (fish), catsharks, flatfish, starfish, sea urchins, crabs, mollusks and other shellfish.
Touch pools have been critiqued for how sanitary they are: humans are often touching the protective mucus of the fish and other wildlife in the tank, leading to potential health complications. Other critiques include the quality of life for the organisms in the tank, and the lack of mimicry of real aquatic environments. Other researchers have evaluated the elevated risk of health impacts for humans who interact with the animals, through potential health concerns.
See also
Shark tunnel
References
Human–animal interaction
Aquariums | Touch pool | [
"Biology"
] | 215 | [
"Human–animal interaction",
"Animals",
"Humans and other species"
] |
77,962,594 | https://en.wikipedia.org/wiki/Mucorrhea | Mucorrhea or mucorrhoea is discharge of mucus, especially when excessive.
The term may refer to mucous rectal discharge or refer to the emission of a large amount of mucus through the feces.
The term mucorrhea' or cervical mucorrhea is also used in gynecology and refers to increased cervical discharge at ovulation.
Causes
Simple traces of mucus are not an expression of any pathology, because it is normal physiology, while an excessive quantity of the substance could simply arise from excessive stimulation of the anus.
Excessive emission of mucus without defecation can indicate anal lesions, even of tumor origin, or pathologies such as colitis, ulcerative colitis, intestinal dysbiosis, gonorrhea, food intolerances, chronic constipation, etc. If, however, it is present at the time of defecation, it could be a symptom of internal lesions. In this case, in addition to tumor masses, there may be chronic inflammatory diseases, or the presence of mucus could occur due to constipation, hemorrhoids, anal fissures, mucorectal prolapses, rectocele.
A study on 31 patients shows that majority of patients with solitary rectal ulcer syndrome present with mucorrhoea. A study on a 36-year-old woman with solitary rectal ulcer syndrome also shows that the patient presents with mucorrhea.
Irritable bowel syndrome (IBS) patients may also present with mucorrhoea.
See also
Anal canal
Ulcerative colitis
Diarrhea
Spinnbarkeit
References
Bibliography
Medical signs
Defecation | Mucorrhea | [
"Biology"
] | 356 | [
"Excretion",
"Defecation"
] |
77,963,491 | https://en.wikipedia.org/wiki/Mothra%20%28star%29 | Mothra, or EMO J041608.838-240358.60, is a binary system with a possible transient, in the constellation of Eridanus. Mothra is in the galaxy cluster MACS J0416.1-2403, nicknamed the "Christmas Tree Galaxy Cluster".
Distance and galaxy
Mothra is one of the most distant known stars; it is 5.4 gigaparsecs (17.6 billion light years) away. They had to magnify to a factor of 4,000 to find EMO J041608.838-240358.60. EMO stands for extremely magnified object. LS1 is the host galaxy of the EMO J041608.838-240358.60 system, a dwarf galaxy or globular cluster with a mass of 10,000-1,000,000 solar masses.
Physical properties
Mothra consists of two supergiant stars, a yellow supergiant and a blue supergiant. Mothra A is a yellow supergiant or yellow hypergiant. It has a size of 271 solar radii, based on a luminosity of 50,000 solar luminosities and a temperature of 5,250 kelvin. Mothra A has an initial mass of 15 solar masses. Mothra B is the blue supergiant. It has an size of 95.5 solar radii based on a luminosity of 125,000 solar luminosities and a temperature of 14,000 kelvin. The orbital characteristics of the binary system is currently unknown. Mothra A had a possible transient event, for 120-230 days it swelled up to 3,000 solar radii, and cooled down to 4,000 kelvin.
See also
Godzilla (star), another kaiju star.
References
Binary systems
Eridanus (constellation) | Mothra (star) | [
"Astronomy"
] | 392 | [
"Eridanus (constellation)",
"Astronomical objects",
"Constellations",
"Binary systems"
] |
77,963,815 | https://en.wikipedia.org/wiki/Bitcoin%20Satoshi%20Vision | Bitcoin Satoshi Vision (BSV) is a cryptocurrency that is a hard fork of Bitcoin Cash. Bitcoin Satoshi Vision was created in November 2018 by a group of individuals led by Craig Steven Wright, who has claimed since 2015 to be Satoshi Nakamoto, the creator of the original bitcoin.
History
2018 Split from Bitcoin Cash
On 15 November 2018, a hard fork chain split of Bitcoin Cash occurred between two rival factions called Bitcoin Cash and Bitcoin SV. On 15 November 2018 Bitcoin Cash traded at about $289, and Bitcoin SV traded at about $96.50, down from $425.01 on 14 November for the un-split Bitcoin Cash.
The split originated from what was described as a "civil war" in two competing Bitcoin Cash camps. The first camp, supported by entrepreneur Roger Ver and Jihan Wu of Bitmain, promoted the software entitled Bitcoin ABC (short for Adjustable Blocksize Cap), which would maintain the block size at 32 MB. The second camp led by Craig Steven Wright and billionaire Calvin Ayre put forth a competing software version Bitcoin SV, short for "Bitcoin Satoshi Vision", which would increase the block size limit to 128 MB.
2019 De-Listing from Binance
In April 2019, an online feud broke out between those who supported the claims of Bitcoin SV supporter Craig Wright that he was Satoshi Nakamoto, and those who did not. The feud resulted in cryptocurrency exchange Binance de-listing Bitcoin SV from their platform, stating that
"At Binance, we periodically review each digital asset we list to ensure that it continues to meet the high level of standard we expect. When a coin or token no longer meets this standard, or the industry changes, we conduct a more in-depth review and potentially delist it. We believe this best protects all of our users.
When we conduct these reviews, we consider a variety of factors. Here are some that drive whether we decide to delist a digital asset:
- Commitment of team to project
- Level and quality of development activity
- Network / smart contract stability
- Level of public communication
- Responsiveness to our periodic due diligence requests
- Evidence of unethical / fraudulent conduct
- Contribution to a healthy and sustainable crypto ecosystem"
2021 Network Attack
In August 2021, Bitcoin SV suffered a 51% attack, after previously suffering attacks in June and July of the same year. Such an attack involves cryptocurrency miners gaining control of more than half of a network's computing power; these kinds of network attacks have the goal of preventing new transactions from gaining confirmations, allowing the attackers to double-spend coins. Adam James, senior editor at OKEx Insights claimed that "In the intermediate term, the attack has seemingly somewhat-negligible impact on its current price action," however "Faith in [Bitcoin SV] will likely be reduced following the incident."
2024 High Court Ruling
In March 2024, Mr Justice James Mellor in the British High Court ruled that Wright is not Satoshi Nakamoto.
See also
Bitcoin scalability problem
List of bitcoin forks
List of cryptocurrencies
References
Cryptography
Bitcoin
Bitcoin clients
Currency | Bitcoin Satoshi Vision | [
"Mathematics",
"Engineering"
] | 689 | [
"Applied mathematics",
"Cryptography",
"Cybersecurity engineering"
] |
77,964,607 | https://en.wikipedia.org/wiki/Levacetylleucine | Levacetylleucine, sold under the brand name Aqneursa, is a medication used for the treatment of neurological manifestations of Niemann-Pick disease type C. Levacetylleucine is a modified version of the amino acid leucine (N-Acetyl-L-Leucine). It is the L form of acetylleucine. It is taken by mouth.
The most common side effects include abdominal pain, difficulty swallowing, upper respiratory tract infections, and vomiting.
Levacetylleucine was approved for medical use in the United States in September 2024. Levacetylleucine is the second medication approved by the US Food and Drug Administration (FDA) for the treatment of Niemann-Pick disease type C. The FDA considers it to be a first-in-class medication.
Medical uses
Levacetylleucine is indicated for the treatment of neurological manifestations of Niemann-Pick disease type C in people weighing at least .
Adverse effects
The most common side effects include abdominal pain, difficulty swallowing, upper respiratory tract infections, and vomiting.
Levacetylleucine may cause embryo-fetal harm if used during pregnancy.
History
The safety and efficacy of levacetylleucine for the treatment of Niemann-Pick disease type C were evaluated in a randomized, double-blind, placebo-controlled, two-period, 24-week crossover study. The duration was twelve weeks for each treatment period. The study enrolled 60 participants. To be eligible for the study participants had to be four years of age or older with a confirmed diagnosis of Niemann-Pick disease type C and at least mild disease-related neurological symptoms. Participants could receive miglustat, an enzyme inhibitor, as background treatment in the study.
The US Food and Drug Administration (FDA) granted the application for levacetylleucine priority review, fast track, orphan drug, and rare pediatric disease designations. The FDA granted approval of Aqneursa to IntraBio Inc.
Society and culture
Legal status
Levacetylleucine was approved for medical use in the United States in September 2024.
Names
Levacetylleucine is the international nonproprietary name.
Research
N-Acetyl-L-Leucine is being studied for the treatment of GM2 gangliosidoses (Tay-Sachs and Sandhoff diseases), ataxia-telangiectasia, Lewy body dementia, amyotrophic lateral sclerosis, restless legs syndrome, multiple sclerosis, and migraine.
References
Further reading
External links
Amides
Amino acids
Orphan drugs | Levacetylleucine | [
"Chemistry"
] | 541 | [
"Amino acids",
"Biomolecules by chemical classification",
"Amides",
"Functional groups"
] |
77,965,598 | https://en.wikipedia.org/wiki/Ahmed%20Almheiri | Ahmed Almheiri (Arabic: أحمد المهيري) is an Emirati theoretical physicist. He is currently an assistant professor of physics at New York University Abu Dhabi, Saadiyat Island. He is known for his works on the AdS/CFT correspondence, black hole information paradox and black hole firewalls.
Education and career
Ahmed completed his undergraduate studies from University of Toronto in 2008. He obtained his Ph.D in physics from University of California, Santa Barbara in 2014 under the supervision of Joseph Polchinski. His thesis titled The Black Hole Firewall and Top-Down Constructions of AdS/CFT was awarded the Winifred and Louis Lancaster Dissertation Award in 2014. He has held postdoctoral positions at Stanford University (2014–17) where he worked on the realization of the AdS/CFT correspondence as a quantum error correction code, and at the Institute for Advanced Study (2017–22) during which he made contributions to calculating the entropy for the radiation of a black hole. He joined New York University Abu Dhabi as a faculty member since 2022.
Awards
Ahmed was jointly awarded the New Horizons in Physics Prize by the Fundamental Physics Prize Foundation in 2021 for "calculating the quantum information of a black hole and its radiation". He was awarded the Pride of Emirates medal in 2020 by His Highness Sheikh Mohammed Bin Rashid Al Maktoum. In November 2024, he was jointly awarded the Mohammed bin Rashid Knowledge Award (MBRKA) by the Mohammed bin Rashid Al Maktoum Foundation.
Research publications
A list of Ahmed's research publications can be found in the INSPIRE HEP database.
Books
Ahmed served as an editor for the autobiographical memoir Memories of a Theoretical Physicist by Joseph Polchinski.
References
External links
Profile in the Mathematics Genealogy Project
Profile in the Physics Academic Tree
1986 births
Emirati scientists
Theoretical physicists
Living people | Ahmed Almheiri | [
"Physics"
] | 376 | [
"Theoretical physics",
"Theoretical physicists"
] |
77,965,739 | https://en.wikipedia.org/wiki/Verrucaria%20fuscozonata | Verrucaria fuscozonata is a rare species of saxicolous (rock-dwelling) crustose lichen in the family Verrucariaceae. It is only known to occur in a single location in northeastern Finland.
Taxonomy
Verrucaria fuscozonata was described as new to science in 2020 by the Finnish lichenologists Juha Pykälä, Annina Kantelinen and Leena Myllys. It belongs to the genus Verrucaria, a group of lichens characterised by their small, flask-shaped fruiting bodies (perithecia) and crustose growth form. While it shares some morphological similarities with other Verrucaria species, particularly those in the V. subtilis complex, V. fuscozonata is genetically distinct. Its unique genetic profile, based on internal transcribed spacer sequence analysis, sets it apart from other known Verrucaria species.
Description
The thallus (lichen body) of Verrucaria fuscozonata is pale grey and primarily , meaning it grows within the rock rather than on its surface. A distinctive feature of this species is the presence of dark lines between adjacent thalli, which gives rise to its species epithet fuscozonata, referring to these dark zonal markings.
The perithecia are small (0.11–0.26 mm in diameter) and mostly in the rock, leaving shallow to deep pits. They are relatively numerous, with 120–140 perithecia per square centimetre. A key diagnostic feature of V. fuscozonata is its , an outer layer covering the perithecium. In this species, the involucrellum extends to the base of the perithecium and is tightly appressed to it, measuring 50–60 μm in thickness.
The spores of V. fuscozonata are moderately large for the genus, measuring 21–29 μm long and 10–13 μm wide. They are non-septate (lacking internal divisions) and enclosed in a thin .
Habitat and distribution
Verrucaria fuscozonata is known only from a single location in northeastern Finland, specifically in the Oulanka area of the Koillismaa region. The only known specimen was found growing on dolomite rock on a river shore.
This highly restricted distribution makes V. fuscozonata one of the rarest known Verrucaria species in Finland. Its apparent preference for dolomite substrate in a riparian environment suggests it may have specific ecological requirements, though more research is needed to confirm this. The species' rarity and limited known distribution make it a subject of interest for further lichenological surveys in Finland and potentially in neighbouring regions with similar geological features.
See also
List of Verrucaria species
References
fuscozonata
Lichen species
Lichens described in 2020
Lichens of Northern Europe
Species known from a single specimen
Taxa named by Leena Myllys | Verrucaria fuscozonata | [
"Biology"
] | 609 | [
"Individual organisms",
"Species known from a single specimen"
] |
77,967,710 | https://en.wikipedia.org/wiki/AR%20Cephei | AR Cephei (AR Cep) is a variable star in the constellation Cepheus. It is classified as a semiregular star, and has a maximum apparent magnitude of +7.32.
Distance
AR Cephei is located approximately 1,114 light-years (350 parsecs) from the Solar System, and has a radial velocity of -14.58000 ± 0.48 km/s, meaning that it is moving toward the Sun at ~14 kilometers every second.
History
Aernout de Sitter discovered the star in 1933. It was given its variable star designation, AR Cephei, in 1939.
See also
List of variable stars
T Cephei
References
Semiregular variable stars
Cephei, AR
Cepheus (constellation)
Variable stars | AR Cephei | [
"Astronomy"
] | 161 | [
"Constellations",
"Cepheus (constellation)"
] |
77,967,774 | https://en.wikipedia.org/wiki/Rings%20of%20Earth | The rings of Earth are a proposed set of planetary rings that may have at one point been present around Earth during the Ordovician period. These rings may have formed during the Ordovician impact spike approximately 466 million years ago. They were first formally proposed by a team of scientists working with the Monash University in September 2024, and have been a subject of interest for several years prior to the study.
Background
The Ordovician Period was the geologic period and system that the Earth was in when the rings are believed to have formed. The Ordovician spanned from million years ago to million years ago. During this period, an event known as the Ordovician meteor event occurred, when a high level of L chondrite meteorites hit Earth. The meteorites may have been caused by a large parent body that was in diameter.
History
Formation
The parent body that produced the L chondrite meteorites is believed to have passed Earth's Roche limit, leading to the body being torn apart and its debris being scattered around, which eventually led to the formation of a debris ring.
Post-formation
The rings are believed to have been present approximately 466 million years ago. The Hirnantian glaciation may be a direct result of the rings shielding light from reaching the Earth, and the rings may have existed for up to 40 million years.
Studies
2024 study
The ring was first formally proposed after 21 impact craters from the meteor event were found to be located along a straight band around the Earth's equator. Andrew G. Tomkins, Erin L. Martin and Peter A. Cawood, working with Monash University, released a study in September 2024 that gave evidence on the existence of the rings.
The study noted that all 21 craters produced as a result of the meteor event fell within an equatorial band range of ≤30°, despite the fact that ~70% of the Earth has a crust suitable for the preservation of craters. The study also noted that the chances of all 21 craters falling within the 30° range was one in 25 million, and would be highly unlikely unless the craters were caused by a dissolved ring system.
See also
Rings of Rhea, a set of theorized rings around Rhea
References
Hypothetical astronomical objects
Earth sciences
20240912
Planetary rings
Solar System | Rings of Earth | [
"Astronomy"
] | 468 | [
"Astronomical hypotheses",
"Outer space",
"Astronomical myths",
"Hypothetical astronomical objects",
"Astronomical objects",
"Solar System"
] |
77,968,114 | https://en.wikipedia.org/wiki/Stellar%20flyby | Stellar flyby refers to the close passage of two or more stars, which remain unbound after their passage
Close encounters with the Sun
The Sun resides in a region of relatively low stellar density in the Milky Way. Thus, close stellar flybys are relatively rare. However, once in a while a star can come relatively close. One example is Scholz's star (WISE designation WISE 0720−0846 or fully WISE J072003.20−084651.2), which is a dim binary stellar system 22 light-years (6.8 parsecs) from the Sun in the constellation Monoceros near the galactic plane. The system passed through the Solar System's Oort cloud roughly 70,000 years ago. Gliese 710 or HIP 89825, an orange 0.6 M☉ star in the constellation Serpens Cauda, is projected to pass near the Sun in about 1.29 million years at a predicted minimum distance of 0.051 parsecs—0.1663 light-years (10,520 astronomical units) (about 1.60 trillion km) – about 1/25th of the current distance to Proxima Centauri.
Close flybys in different environments
Close flybys are usually relatively rare among field stars, but are more common in star clusters In these groups of stars the stellar density is much higher, so that close passages of between stars are more common. In particular in young star clusters, open clusters and globular clusters stellar flybys are thought to be common. In young clusters, such close stellar flybys might influence the frequency and size of protoplanetary discs, and influence the planet formation process in these environments.
References
Astronomy | Stellar flyby | [
"Astronomy"
] | 357 | [
"nan"
] |
77,968,557 | https://en.wikipedia.org/wiki/D-square%20law | The d-square law or -law is a relationship between diameter and time for an isolated, spherical droplet when it evaporates quasi-steadily, which was first observed by Boris Sreznevsky in 1882, and was explained by Irving Langmuir in 1918. If and are the droplet diameter and time, then -law pertains to the relation
where is the initial time, is the initial droplet diameter and is called the evaporation constant.
References
Equations of fluid dynamics
Combustion | D-square law | [
"Physics",
"Chemistry"
] | 103 | [
"Equations of fluid dynamics",
"Equations of physics",
"Combustion",
"Fluid dynamics stubs",
"Fluid dynamics"
] |
77,970,038 | https://en.wikipedia.org/wiki/Stuff%20Matters | Stuff Matters: Exploring the Marvelous Materials That Shape Our Man-Made World is a 2014 non-fiction book by the British materials scientist Mark Miodownik. The book explores many of the common materials people encounter during their daily lives and seeks to explain the science behind them in an accessible manner. Miodownik devotes a chapter each to ten such materials, discussing their scientific qualities alongside quirky facts and anecdotes about their impacts on human history. Called "a hugely enjoyable marriage of science and art", Stuff Matters was critically and commercially successful, becoming a New York Times best seller and a winner of the Royal Society Prize for Science Books.
Background
Miodownik was working at University College London as a professor of materials and society at the time the book was published. He first gained interest in his field of study during his teenage years following an attempted robbery while on the subway. He was stabbed with a razor through multiple layers of clothing, leading him to be curious about the qualities of steel that provided for such a sharp and strong edge. The author would go on to earn a doctorate in jet engine alloys before entering into academic work. He was an occasional presenter on instructional television programs, and the year after publishing Stuff Matters he was the recipient of the American Association for the Advancement of Science's Public Engagement with Science Award. Stuff Matters was the author's first published popular science work.
Synopsis
Each of the book's chapters begins with the same photograph of Miodownik sitting on the rooftop of his London apartment. In each iteration of the photo, a different object is circled a teacup in one chapter, a flowerpot in another, and so on with that chapter focused on the history and science of the material of which the highlighted item consists. Over the course of the book, Miodownik covers a number of materials that have been around for a long time (steel, paper, glass, porcelain), some introduced last century (concrete, plastics, carbon fiber), and a few relatively new inventions (graphene, aerogels). He includes a chapter on chocolate due in large part to his own obsession with the sweet. Miodownik seeks to draw connections from the materials to the lives of the people who use them, saying, "The material world is not just a display of our technology and culture, it is part of us. We invented it, we made it, and in turn, it makes us who we are."
The author takes varying approaches to explaining each material's attributes and their importance, since according to him, the "materials and our relationships with them are too diverse for a single approach to suit them all". In the process of describing the book's subjects he intersperses scientific knowledge with insights into the materials' impacts on human history. For instance, historically the Chinese had a technological edge over the rest of the world in many respects (they alone held the secret to making porcelain for hundreds of years, for one example). However, their culture preferred other materials over glass, and Miodownik surmises that the resulting lack of advancement with that substance later held the culture back scientifically, as glass is a key component in such tools as microscopes and telescopes. Elsewhere, the author describes how the sudden 19th-century surge in popularity of billiards can be linked to the invention of both nylon and vinyl (the need for a cheap alternative to ivory for making pool balls led to the increased development of celluloid, the success of which led to further innovation in plastics).
While much of the book relates the history of the selected materials, Miodownik also devotes time to many of their futures, including the development of a type of concrete that is infused with bacteria meant to self-repair cracks as they occur. Also described are aerogels, which are ultralight materials that are the best thermal insulators known to man. Composed of over 99% air, these materials are able to produce Rayleigh scattering in much the same way as the Earth's atmosphere, thereby appearing blue to the naked eye. This effect, combined with the aerogel's light weight, leads Miodownik to say that holding a sample is "like holding a piece of sky". The material is extremely expensive to make, however, and outside of occasional specific applications for NASA (it was a key component of that agency's Stardust mission), practical uses have been difficult to find.
Miodownik writes that civilization is built on the materials around us, and that we acknowledge their importance by naming our historical eras after them. The Stone, Bronze, and Iron Ages are well known, and Miodownik argues that the steel age likely began in the late 19th century and we could be considered to be currently living in the silicon age. The constant desire for improvements in our lives (improved comfort, improved safety, etc.) drives the constant improvements to the materials that comprise our world. Therefore, Miodownik concludes, materials are "a multi-scale expression of our human needs and desires".
Reception
Stuff Matters was a New York Times best seller and won the 2014 Royal Society Prize for Science Books as well as the 2015 National Academies Communication Award. The book released to generally positive reviews. Writing for The New York Times Book Review, Rose George praised Miodownik's blend of science and storytelling. The Wall Street Journal called it a "thrilling account of the modern material world", while The Independent was impressed with the "learned, elegant discourse" Miodownik conducts in each chapter. The Observer Robin McKie considered the book "deftly written" and appreciated the author's conclusions drawn from the historical record. The reviewer for the Financial Times enjoyed the book but was critical of the occasional error, as when Miodownik mistakenly identifies the Greek word for chocolate as being much older than it is.
The reviewer for Entertainment Weekly wrote that Miodownik occasionally lapsed into technical speak in a book meant for a broader audience, but that the author's clear enthusiasm for his subject outweighed any such negative aspects. Science News considered Miodownik's explanations of the more science-intensive material to be accessible and praised the humor interspersed throughout the book. Stuff Matters was well-received by certain trade journals as well. The American Ceramic Society Bulletin wrote that Miodownik's writing worked both as an introduction to the layperson as well as a "reminder of the field's broad purpose" for those with more knowledge on the subject, while the journal of the Boston Society of Architects particularly enjoyed the book's chapter on concrete. Bill Gates reviewed the book favorably on his website, writing, "In political contests, voters sometimes put more weight on whether they'd like to have a beer with a candidate than on the candidate's qualifications. Miodownik would pass anyone's beer test, and he has serious qualifications."
References
English-language non-fiction books
2014 non-fiction books
Materials science
Houghton Mifflin books
Science books | Stuff Matters | [
"Physics",
"Materials_science",
"Engineering"
] | 1,437 | [
"Applied and interdisciplinary physics",
"Materials science",
"nan"
] |
77,970,049 | https://en.wikipedia.org/wiki/S%20Cephei | S Cephei (S Cep), also designated as HD 206362, is a carbon star and Mira-type variable in the constellation Cepheus. Based on the measurement of its annual parallax by the Gaia satellite, the star is approximately ∼1,590 ly (∼487 pc) away from Earth.
The Gaia satellite shows anomalies in the proper motion of S Cephei compared to its long-term proper motion. These anomalies could indicate the presence of an orbiting companion such as a red dwarf or a brown dwarf.
S Cephei is a carbon star of spectral type C7.3e. It is also a Mira-type variable star whose apparent magnitude varies from 6.6 to 12.5 in the form of a pulsation over a period of 484 days. Its variability was discovered by Karl Hencke in 1858.
See also
Mu Cephei
ST Cephei
References
Variable stars
Cepheus (constellation)
Supergiants | S Cephei | [
"Astronomy"
] | 202 | [
"Constellations",
"Cepheus (constellation)"
] |
77,970,596 | https://en.wikipedia.org/wiki/Mira%20Doig | Mira Victoria Doig is a British biochemist and analytical chemist known for her contributions to mass spectrometry.
After attending Sittingbourne Girls Grammar School, Diog completed her undergraduate degree in biochemistry at the University of London. In 1981, she completed her doctoral studies in analytical chemistry.
Doig worked in industry starting at Glaxo Wellcome before moving to ABS Laboratories in 1996. Since 2023, she has worked at Bioapp Solutions, and as the Chief Scientific Officer for MC Analytical.
Doig was chair of the British Mass Spectrometry Society from 2004 to 2006. She was awarded life membership by the Society for her contributions to mass spectrometry.
References
Mass spectrometrists
Alumni of the University of London
Year of birth missing (living people)
Living people
British biochemists
Scientists from Kent | Mira Doig | [
"Physics",
"Chemistry"
] | 169 | [
"Biochemists",
"Mass spectrometry",
"Spectrum (physical sciences)",
"Mass spectrometrists"
] |
77,971,726 | https://en.wikipedia.org/wiki/Armesocarb | Armesocarb (developmental code name MLR-1019), also known as (R)-mesocarb or L-mesocarb, is a selective atypical dopamine reuptake inhibitor (DRI). It is currently under development for the treatment of Parkinson's disease and sleep disorders.
It is the active (R)-enantiomer of the formerly clinically used stimulant-like drug mesocarb (MLR-1017; brand name Sydnocarb).
Pharmacology
Mesocarb is known to be a highly selective DRI. However, in 2021, it was discovered that mesocarb is not a conventional DRI but acts as a dopamine transporter (DAT) allosteric modulator or non-competitive inhibitor.
In accordance with its nature as an atypical DAT blocker, the drug exhibits atypical effects compared to conventional DRIs. For example, mesocarb shows greater antiparkinsonian activity in animals compared to other DRIs.
Mesocarb has wakefulness-promoting effects in animals. Armesocarb, as the active enantiomer of mesocarb, shows greater therapeutic potency than the racemic form in animals. In contrast, the (S)- or D-enantiomer of mesocarb is virtually inactive in animal behavioral tests.
History
Armesocarb was first described in the scientific literature as an enantiopure compound by 2005 and again in 2017.
Clinical studies
As of April 2023, armesocarb is undergoing phase 1 clinical trials for Parkinson's disease and is in preclinical development for sleep disorders. The latter indication may specifically target excessive daytime sleepiness (EDS) in people with Parkinson's disease. Armesocarb is also in development for the treatment of levodopa-induced dyskinesia.
See also
MRZ-9547 ((R)-phenylpiracetam)
List of Russian drugs
References
Anilides
Antidyskinetic agents
Antiparkinsonian agents
Dopamine reuptake inhibitors
Enantiopure drugs
Experimental drugs
Imines
Oxadiazoles
Stimulants
Substituted amphetamines
Ureas
Wakefulness-promoting agents | Armesocarb | [
"Chemistry"
] | 480 | [
"Organic compounds",
"Stereochemistry",
"Enantiopure drugs",
"Ureas"
] |
77,972,365 | https://en.wikipedia.org/wiki/Mesdopetam | Mesdopetam (; developmental code names IRL-790, IPN60170) is a dopamine D2 and D3 receptor antagonist with preference for the D3 receptor which is under development for the treatment of Parkinson's disease, drug-induced dyskinesia, and psychotic disorders. It has been described by its developers as having "psychomotor stabilizing" properties.
Pharmacology
The described intention behind mesdopetam was to develop a novel dopamine D2 and D3 receptor antagonist based on agonist- rather than antagonist-like structural motifs and with agonist-like physicochemical properties (e.g., smaller molecular size, greater hydrophilicity). It was hypothesized that this would result in an antagonist with specific dopamine receptor interactions more similar to those of agonists like dopamine but without any intrinsic activity, in turn resulting in different in vivo effects than conventional dopamine receptor antagonists. Specifically, antidyskinetic and antipsychotic effects with fewer or no motor side effects was sought. There is also extensive preclinical research to suggest that D3 receptor antagonists reduce levodopa-induced dyskinesia without compromising the antiparkinsonian effects of levodopa.
Mesdopetam has 6- to 8-fold preference for the dopamine D3 receptor (Ki = 90nM) over the dopamine D2 receptor (Ki = 540–750nM). It displays a paradoxical agonist-like binding mode in spite of its lack of activational efficacy. By antagonizing D3 autoreceptors, D3 receptor antagonists like mesdopetam have been found to disinhibit dopamine release in the prefrontal cortex, ventral tegmental area, and striatum, which might be involved in the possible therapeutic benefits of these agents. The drug is also a ligand of the sigma σ1 receptor (Ki = 870nM) and has some affinity for certain serotonin receptors including the serotonin 5-HT1A and 5-HT2A receptors. In animals, mesdopetam has no effect on spontaneous locomotor activity at assessed doses but antagonizes levodopa-induced dyskinesia and reduces dextroamphetamine- and dizocilpine-induced locomotor hyperactivity.
Side effects
Side effects of mesdopetam in clinical trials have been reported to include worsened parkinsonism, headache, fatigue, asthenia, and dissociation.
Clinical development
Mesdopetam was first described in the literature in 2012. As of September 2024, it is in phase 2/3 clinical trials for Parkinson's disease, phase 1 trials for drug-induced dyskinesia, and is in preclinical development for psychotic disorders (specifically Parkinson's disease psychosis). It is also of interest for potential treatment of impulse control disorders. In 2019, mesdopetam received an with a novel -"dopetam" suffix supposedly representing a new mechanism of action among dopamine receptor modulators. In 2023, it was reported that mesdopetam failed to meet a primary anti-dyskinetic endpoint in a phase 2b trial. However, indications of efficacy were still seen and a phase 3 trial is being planned. No dopamine D3 receptor antagonists have yet completed development or been approved for the treatment of levodopa-induced dyskinesia.
See also
Pirepemat
References
External links
Mesdopetam - AdisInsight
Mesdopetam (IRL790) - IRLAB Therapeutics
Amines
Antidyskinetic agents
Antipsychotics
D2 antagonists
D3 antagonists
Experimental drugs
Fluoroarenes
Organosulfur compounds
Sigma receptor ligands | Mesdopetam | [
"Chemistry"
] | 811 | [
"Organosulfur compounds",
"Functional groups",
"Organic compounds",
"Amines",
"Bases (chemistry)"
] |
77,972,999 | https://en.wikipedia.org/wiki/Truncated%20triangular%20pyramid%20number | A truncated triangular pyramid number is found by removing (truncating) some smaller tetrahedral number (or triangular pyramidal number) from each of the vertices of a bigger tetrahedral number.
The number to be removed (truncated) may be same or different from each of the vertices.
Properties
A truncated number is not the same as the volume or area of the truncated shape.
Instead numbers relate more to the problem of how densely given solid objects can pack in space. Dense packing of convex objects is related to problems like the arrangement of molecules in condensed states of matter and to the best way to transmit encoded messages over a noisy channel. Kepler's conjecture, which postulated that the densest packings of congruent spheres in 3-dimensional space have packing density (fraction of space covered by the spheres) = pi / sqrt 18 = 74.048% was proved by variants of the face-centered cubic (FCC) lattice packing.
It is hypothesised that a regular tetrahedron might possibly be the convex body having the smallest possible packing density. In contrast to this, the densest known packing of truncated tetrahedra can have an exceptionally high packing fraction φ = 207/208 = 0.995192...
Truncated numbers are also relevant to cluster science in inorganic chemistry. Central to the chemical and physical study of clusters is a understanding of their molecular and electronic structures which is determined by the number of atoms in a cluster of given size and shape and their arrangement or disposition. Semiconductors are one of the most active areas of cluster research.
Examples
Tetrahedral Number 20 yields Truncated Triangular Pyramid Number 7 by truncating Tetrahedral number (or triangular pyramidal number) 4,4,4 and 1 from its vertices
Tetrahedral Number 35 yields Truncated Triangular Pyramid Number 19 by truncating Tetrahedral number (or triangular pyramidal number) 4 from each of the vertices
Tetrahedral Number 286 yields Truncated Triangular Pyramid Number 273 by truncating Tetrahedral number (or triangular pyramidal number) 4,4,4 and 1 from its vertices
Tetrahedral Number 560 also yields Truncated Triangular Pyramid Number 273 by truncating Tetrahedral number (or triangular pyramidal number) 84,84,84 and 35 from its vertices
Tetrahedral Number 816 yields Truncated Triangular Pyramid Number 689 by truncating Tetrahedral number (or triangular pyramidal number) 56,35,35 and 1 from its vertices
Tetrahedral Number 969 yields Truncated Triangular Pyramid Number 833 by truncating Tetrahedral number (or triangular pyramidal number) 56,35,35 and 10 from its vertices
Related numbers
Certain truncated triangular pyramid numbers possess other characteristics:
273 (number) is also a sphenic number and an idoneal number
204 (number) is also a square pyramidal number and a nonagonal number
In other fields
Truncated triangular silver nanoplates synthesized in large quantities using a solution phase method
Theoretical study of hydrogen storage in a truncated triangular pyramid molecule
Packing and self-assembly of truncated triangular bipyramids
References
Numbers | Truncated triangular pyramid number | [
"Mathematics"
] | 626 | [
"Figurate numbers",
"Mathematical objects",
"Numbers"
] |
77,973,234 | https://en.wikipedia.org/wiki/E-Defense | The 3-D Full-Scale Earthquake Testing Facility or E-Defense () is an earthquake shaking table facility in Miki, Hyōgo Prefecture, Japan. Operated by the Japanese National Research Institute for Earth Science and Disaster Resilience (NIED), it was the largest 3D earthquake shake table in the world when it was commissioned.
History
After the destructive Great Hanshin earthquake of 1995, the Science and Technology Agency established a round-table conference, which in May 1996 recommended that an earthquake research centre be founded to prevent future earthquake damage in urban areas. It was recommended that the research centre should have a three-dimensional shake table.
Development of the table's actuators began in 1995, and the design and construction of E-Defense began in 1998 or 1999 (sources vary), intending to replicate the ground motions of the Great Hanshin earthquake. Mitsubishi Heavy Industries machinery systems designed and constructed the facility, which is located at Miki Earthquake Disaster Memorial Park. Construction of the table's foundation started in 1999 and was completed in 2001. Operations began in 2005 after a total construction cost of 45 billion yen. The nickname "E-Defense" was selected in a public competition, with the letter "E" standing for Earth.
E-Defense could not reproduce the ground motions of the 2011 Tōhoku earthquake due to the long period and long duration of the shaking. NIED tried to simulate the ground motions of this earthquake for five minutes but was initially only able to manage 1.5 minutes of shaking due to insufficient oil for the actuators. After more accumulators were installed and bypass valves were added to the actuators, they achieved the goal of five minutes of sustained shaking.
Facility
The table is 20 by 15 metres (an area of 300 square metres), making it the largest earthquake shaking table in the world when it was constructed. It can move in the x, y, and z directions and perform yaw, pitch, and roll rotations. It can accelerate up to 1 g horizontally in both directions and up to 1.5 g vertically. It can have a maximum payload of 1,200 tons. The table has five horizontal actuators for both directions and 14 vertical actuators, each with a maximum driving force of 4,500 kilonewtons. They can generate frequencies with good accuracy up to 15 hertz and can be increased to 30 hertz with lower accuracy. Universal joints are placed between the actuators and the table.
The facility is on a six-hectare site, which includes several buildings. These are the experiment building, which contains the shaking table; the operation building, which contains the control system for the shaking table; the hydraulic unit building, which contains equipment that powers the shaking table; and the preparation building, where test structures are prepared.
Experiments
As of 2020, 113 experiments have been run on the table, at an average of 7.1 experiments per year. Experiments are either projects run by the NIED, projects run jointly by the NIED and other organisations, or run by other organisations. Most of the design and construction time for experiments takes place outside the main E-Defense facility to maximise the use of the table. Experimental structures are placed onto the table using two cranes with a combined maximum loading capacity of 9000 kilonewtons.
Due to the high cost of running the experiments, it is E-Defense policy that the results not be intellectual property of the conductors of the experiments but instead shared by the international earthquake engineering community. This is so that the results can have a high impact.
References
Further reading
Earthquake engineering
Research institutes in Japan
Miki, Hyōgo
Earthquake and seismic risk mitigation
Science and technology in Japan | E-Defense | [
"Engineering"
] | 752 | [
"Structural engineering",
"Earthquake engineering",
"Earthquake and seismic risk mitigation",
"Civil engineering"
] |
77,973,337 | https://en.wikipedia.org/wiki/WISEA%20J1141%E2%88%923326 | WISEA J1141−3326 (WISE J114156.67-332635.5, W1141) is a Y-dwarf, which means it is one of the coldest directly imaged astronomical objects. It is likely a free-floating planetary-mass object.
W1141 was discovered in 2014 from data of the Wide-field Infrared Survey Explorer and at first the spectral type was estimated to be Y0, but no spectroscopic confirmation was present at the time. In 2017 a spectrum from Gemini South was published, confirming it as a Y0 spectral type. This work found it to be metal-rich, between 100 Myrs and 1 Gyr young and low-mass (3–8 ). It has a tangential velocity of about 41 km/s. It was found that this object overlaps with a background galaxy in early observations, contaminating the measured brightness. This had led to a falsely detection of a blue color, which is attributed to the contamination.
See also
List of Y-dwarfs
References
Brown dwarf stubs
WISE objects
Hydra (constellation)
Rogue planets
Y-type brown dwarfs | WISEA J1141−3326 | [
"Astronomy"
] | 232 | [
"Hydra (constellation)",
"Constellations"
] |
77,973,582 | https://en.wikipedia.org/wiki/CWISEP%20J1446%E2%88%922317 | CWISEP J1446−2317 (CWISEP J144606.62−231717.8, CWISEP 1446−2317) is a brown dwarf or planetary-mass object. It is a Y-dwarf with a spectral type of Y1.
CWISEP J1446−2317 was discovered as an unusual red object (Spitzer ch1-ch2 = 3.71 ±0.44 mag) in the new combined WISE/NEOWISE catalog, called CatWISE. The object was found using supervised machine-learning, by using XGBoost. The temperature was estimated to be lower than 381 Kelvin for this object. Follow-up observations however revised the color to ch1-ch2 = 2.986 ±0.048 mag, making it the fifth reddest object at the time, with an estimated temperature of 310−360 K. The mass was estimated between 2 and 20 for an age range of ~500 Myr–13 Gyr. The object is however unlikely to be young because of its high tangential velocity of around 60 km/s. If this object is similar to other ultracool dwarf in the solar neighbourhood, it would have an age of about 1.5–6.5 Gyrs and therefore a mass of 4–14 according to the authors.
In 2024 observations of CWISEP J1446−2317 with JWST were published. These observations were carried out with NIRSpec and MIRI spectroscopy. These observations established this object to have a spectral type of Y1, due to the narrow J-band peaks. There were however difficulties to precisely determine the spectral type. CWISEP J1446−2317 is not discussed in detail in this work. The authors however mention that they detect absorption features in their sample. These include water vapor, methane, ammonia, carbon monoxide and carbon dioxide. None of the objects in their sample show absorption due to phosphine, which is predicted to be present in the atmosphere of these cold objects.
See also
List of Y-dwarfs
References
Y-type brown dwarfs
Brown dwarf stubs
Astronomical objects discovered in 2020
WISE objects
Rogue planets
Libra (constellation) | CWISEP J1446−2317 | [
"Astronomy"
] | 457 | [
"Libra (constellation)",
"Constellations"
] |
77,973,680 | https://en.wikipedia.org/wiki/ESO%20286-19 | ESO 286-19 known as IRAS 20551-4250, is a galaxy merger located in the constellation of Microscopium. It is located 609 million light years away from Earth. It is an ultraluminous infrared galaxy.
Characteristics
ESO 286-19 is a late-stager merger. A product of two colliding disk galaxies, it is found distorted, with a long tidal tail that is extending to the right from its main body while the shorter tidal tail is curving towards the left direction. It has knotted structures. There is a distribution of cold molecular gas from the galaxy's southeast region.
A single nucleus has been detected in ESO 286–19 by both XMM Newton and Chandra X-ray Observatory although undetected by NuSTAR. According to observations made by Chandra, the soft X-ray emission of the galaxy is elongated while having a point-like hard X-ray emission. However, its polarized flux is faint.
ESO 286-19 is also an extremely bright galaxy with a luminosity of LIR ~ 1012 LΘ. It also experiences a starburst. A spectroscopic and photometric analysis found the galaxy has an old stellar population mass of 3 x 1011 MΘ. It also has much young, recently formed stars of 8 x 109 MΘ contributing to ~ 2 of the stellar mass. The galaxy also has molecular hydrogen with a mass of 4 x 1010 MΘ.
According to results from Cycle 2 observations conducted by Atacama Large Millimeter Array, ESO 286-19 harbors an obscured active galactic nucleus. The nucleus shows HCN/HCO+/HNC J = 3-2 emission lines that are found vibrationally excited with a high energy level of v 2 = 1. Due to a likely line opacity correction, the lines are found to have an excitation temperature and flux ratio amidst v 2 = 1f and v = 0. Additionally, a broad emission line component was found from a CO J = 3-2 emission line with a measurement of full width at half maximum (FWHM) ~ 500 km s−1. This finding suggested it was caused by molecular outflow in the galaxy with a mass of Moutf ~ 5.8 x 106 MΘ and a kinetic power of Poutf ~ 1%. Based on the outflow, it has an X-ray luminosity of L2-10keV = 2.1 x 1041 ergs−1.
References
286-19
Luminous infrared galaxies
20551-4250
065817
Galaxy mergers
Interacting galaxies | ESO 286-19 | [
"Astronomy"
] | 531 | [
"Microscopium",
"Constellations"
] |
77,973,703 | https://en.wikipedia.org/wiki/John%20D.%20Aitchison | John D Aitchison is a Canadian American molecular cell biologist, systems cell biologist, and academic. He serves as a Principal Investigator at Seattle Children's Research Institute and Professor in the Department of Pediatrics, an Affiliate/Adjunct Professor in the Department of Biochemistry, at the University of Washington (UW). Serving as an Affiliate Professor at the Institute for Systems Biology (ISB), he is also an adjunct professor at University of Alberta (UAlberta).
Aitchison's research interests include using systems biology to understand complex biological phenomena. His work has spanned from basic cell biology, using yeast as a model system, focusing on understanding molecular mechanisms of nuclear transport and peroxisome biogenesis and function to host-pathogen interactions, studying how viruses and other pathogens influence cellular function. His research lab also developed and applied systems biology approaches to reveal fundamental insights into cell biology, host-pathogen interactions, and infectious disease.
Education
From 1982 to 1992, Aitchison studied at the Department of Biochemistry at McMaster University, earning his B.Sc. in Biotechnology and Genetic Engineering and his PhD in Biochemistry with Richard Rachubinski. He then served as a Medical Research Council of Canada Post-Doctoral Fellow, followed by an HHMI Post-Doctoral Associate at Rockefeller University with Günter Blobel until 1997.
Career
Aitchison was a scholar for both the Medical Research Council of Canada and the Alberta Heritage Foundation for Medical Research, while also working as an assistant professor at UAlberta. In 2000, he joined ISB in Seattle, as a founding faculty member, where he progressed to director of integrative biology – a position he concurrently held at Seattle Biomedical Research Institute (SBRI), also known as the Center for Infectious Disease Research (CIDR), from 2011 to 2013. Between 2011 and 2018, he held various positions at SBRI/CIDR, including director, senior vice president, executive director, scientific director, chief science officer, and president. In 2018, SBRI/CIDR was integrated into Seattle Children's in 2018, where he codirected the Center for Global Infectious Disease Research through 2024.
Research
Systems cell biology
Aitchison's research into the complex dynamics of cellular organization has focused on peroxisome biogenesis and function as well as nucleocytoplasmic transport.
Aitchison conducted research on peroxisomes which focused on their biogenesis as an integrated program from signaling through transcription, translation, and building the organelle. His group developed technologies, analysis tools and systems approaches, including 'omics, network modeling, machine learning, combined with molecular cell biology.
Aitchison's work in yeast on nuclear transport mechanisms and the nuclear pore complex has led to insights into structure of the nuclear pore complex, and the discovery of a large family of nuclear transport factors – broadly termed karyopherins (aka importins and exportins). Together with his colleagues, he introduced the "virtual gating" model, elucidating the rapid and selective transport of large macromolecules across nuclear pore complexes in eukaryotic cells. His work has also led to the discovery of a role for the nuclear pore complex in control of chromatin organization, and thereby, regulation of gene expression.
Host-pathogen interactions
Aitchison and his lab have conducted research that merges high-throughput technologies, computational biology, and systems biology to understand cellular organization, dynamics, and host-pathogen interactions, especially in global infectious diseases. He unveiled mechanisms shaping cellular dynamics and host-pathogen interactions during infections from viruses and other pathogens. Among insights into host-based immune responses using systems approaches, he proposed that upon infection, viruses induce vulnerabilities into host cells that can be exploited to kill virally infected cells. The proposal is based on the fact that viruses alter host cells in dramatic ways, including hijacking host cell proteins to support viral replication. He showed that such cells can be selectively killed to abrogate virus production using the concept of synthetic lethality.
Covid therapeutics
Aitchison and his colleagues have also developed a cohort of nanobodies from llama antibodies as potent COVID-19 therapeutics and identified effective cocktails that act synergistically to prevent infection and respiratory disease, presenting an approach to combat the respiratory infections and future pandemics.
Selected articles
Aitchison JD, Blobel G, Rout MP. (1996) Kap104p: a karyopherin involved in the nuclear transport of messenger RNA binding proteins. Science 274(5287):624-7
Rout, M. P., Aitchison, J. D., Suprapto, A., Hjertaas, K., Zhao, Y., & Chait, B. T. (2000). The yeast nuclear pore complex: composition, architecture, and transport mechanism. The Journal of Cell Biology, 148(4), 635–652.
Aitchison JD, Rout MP. (2001) The nuclear pore complex as a transport machine. Journal of Biological Chemistry 276 (20), 16593-16596
Ramsey SA, Smith JJ, Orrell D, Marelli M, Petersen TW, de Atauri P, Bolouri H, Aitchison JD. (2006) Dual feedback loops in the GAL regulon suppress cellular heterogeneity in yeast. Nat Genet. 38(9):1082-7
Smith, J. J., & Aitchison, J. D. (2013). Peroxisomes take shape. Nature Reviews Molecular Cell Biology, 14(12), 803–817.
Van de Vosse DW, Wan Y, Lapetina DL, Chen WM, Chiang JH, Aitchison JD, Wozniak RW. (2013) A role for the nucleoporin Nup170p in chromatin structure and gene silencing. Cell.152(5):969-83
Mast FD, Fridy PC, Ketaren NE, Wang J, Jacobs EY, Olivier JP, Sanyal T, Molloy KR, Schmidt F, Rutkowska M, Weisblum Y, Rich LM, Vanderwall ER, Dambrauskas N, Vigdorovich V, Keegan S, Jiler JB, Stein ME, Olinares PDB, Hatziioannou T, Sather DN, Debley JS, Fenyö D, Sali A, Bieniasz PD, Aitchison JD, Chait BT, Rout MP. (2021) Highly synergistic combinations of nanobodies that target SARS-CoV-2 and are resistant to escape. Elife. 2021 10:e73027.
Mast FD, Navare AT, van der Sloot AM, Coulombe-Huntington J, Rout MP, Baliga NS, Kaushansky A, Chait BT, Aderem A, Rice CM, Sali A, Tyers M, Aitchison JD. (2020) Crippling life support for SARS-CoV-2 and other viruses through synthetic lethality. J Cell Biol. 219(10):e202006159
Litvak V, Ratushny AV, Lampano AE, Schmitz F, Huang AC, Raman A, Rust AG, Bergthaler A, Aitchison JD, Aderem A. (2012) A FOXO3-IRF7 gene regulatory circuit limits inflammatory sequelae of antiviral responses. Nature 18;490(7420):421-5
References
Molecular biologists
21st-century American academics
University of Washington faculty
Academic staff of the University of Alberta
McMaster University alumni
Living people
Year of birth missing (living people) | John D. Aitchison | [
"Chemistry"
] | 1,633 | [
"Molecular biologists",
"Biochemists",
"Molecular biology"
] |
77,974,053 | https://en.wikipedia.org/wiki/WISE%20J1206%2B8401 | WISE J1206+8401 (WISE J120604.38+840110.6, WISE 1206+8401) is a brown dwarf or planetary-mass object, discovered in 2015 with WISE and the Hubble Space Telescope. It has the spectral type Y0.
The object was found to be metal-rich in a work from 2017 and the research team found a mass of 6−14 . A later work from 2023 found a mass of 17 ±5 . It was observed with JWST, using NIRSpec and MIRI spectroscopy. This object is not discussed in detail in this work, but the researchers report the detection of molecular absorption features in their sample, including water vapor, methane, ammonia, carbon monoxide and carbon dioxide. None of their objects have any detection of phosphine. One paper mentions that WISE J1206+8401 does have deeper carbon dioxide and carbon monoxide features, when compared to other Y-dwarfs. This makes this Y-dwarf similar to CWISEP J1047+5457.
See also
List of Y-dwarfs
References
Y-type brown dwarfs
Brown dwarf stubs
Astronomical objects discovered in 2015
WISE objects
Rogue planets
Camelopardalis | WISE J1206+8401 | [
"Astronomy"
] | 252 | [
"Camelopardalis",
"Constellations"
] |
70,692,965 | https://en.wikipedia.org/wiki/Black%20Shark%205 | The Black Shark 5, Black Shark 5 Pro and Black Shark 5 RS are Android-based gaming smartphones designed and manufactured by Xiaomi, announced on 30 March 2022.
References
Android (operating system) devices
Mobile phones introduced in 2022
Xiaomi smartphones
Mobile phones with multiple rear cameras
Mobile phones with 4K video recording | Black Shark 5 | [
"Technology"
] | 67 | [
"Mobile technology stubs",
"Mobile phone stubs"
] |
70,692,985 | https://en.wikipedia.org/wiki/Meir%20Bialer | Meir Bialer (born January 30, 1948) is an Israeli pharmacologist who is a David H. Eisenberg Emeritus (active) Professor of Pharmacy at the School of Pharmacy, Faculty of Medicine, of The Hebrew University of Jerusalem in Israel.
Biography
Bialer was born in Petach Tikva, Israel, to a Jewish family. He completed his service in the Israeli Army in 1971-73.
He received his B.Sc. Pharm in Pharmacy in 1969, his M.Sc. in Medicinal Chemistry from The Hebrew University of Jerusalem in 1971, his MBA in 1976 and his PhD in Medicinal Chemistry from the same university in 1977, with a dissertation on "Antiviral Structure-Activity Relationship of Distamycin and its Derivatives."
After post-doctoral studies at the University of Florida (1977–79) and University of Kentucky (1979–80), he became a Lecturer (1980–84) and then Senior Lecturer (1984–88) and then Associate Professor (1988–93) at the School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem. In 1993 he became a Full Professor at the School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem. Currently, he is serving as a David H. Eisenberg Emeritus (active) Professor at the School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem.
Bialer was president of the Israel League Against Epilepsy, a branch of the International League Against Epilepsy (ILAE), from 1996 to 2001, and as the chair of ILAE-Europe from 2009 to 2017. He also served as president of Israel Society of Clinical Pharmacy and Biopharmaceutics (ISCPB), a member of the European Society of Pharmaceutical Sciences (EUFEPS) (1991–2001).
Research work
Bialer’s research interests include:
Pharmacokinetics of new antiepileptic drugs (AEDs) and pharmacokinetic-based design of new antiepileptics and CNS drugs. In this regard he has been utilizing structure pharmacokinetic pharmacodynamic relationship (SPPR) studies to design and develop new CNS drugs with better potency, lack of teratogenicity, and a wide safety margin;
Pharmacokinetic analysis of new drugs, sustained release dosage forms, and novel drug delivery systems (DDS);
Stereospecific pharmacokinetic and pharmacodynamic analysis of chiral drugs;
Pharmacogenetics of CNS drugs;
Pharmacoresistance to AEDs.
In these areas, he has 264 peer-reviewed publications, and is an author of 16 book chapters. Since 1981 he has supervised 22 MSc students and 31 PhD students.
Awards
A Fellow of the American Association of Pharmaceutical Sciences - AAPS (1992)
Kaye Innovation Awards at The Hebrew University of Jerusalem (2000, 2006, and 2007)
Ambassador for Epilepsy Award of The International League Against Epilepsy – ILLAE and The International Bureau for Epilepsy (IBE; 2001)
European Epileptology Award (2022)
Personal life
Meir married Shoshana Novak in 1970. They have two children Michal Bialer-Mor Yosef and Oded Bialer, as well as five grandchildren: Adi, Omri and Roni Bialer and Adam and Eitan Mor Yosef.
Selected publications
S. Eyal, B. Yagen, E. Sobol, Y. Altschuler, M. Shmuel and M. Bialer: The activity of antiepileptic drugs as histone deacetylase inhibitors. Epilepsia 45:737-744 (2004).
M. Bialer, D.R. Doose, B. Murthy, C. Curtin, S-S Wang, R.E. Twyman and S. Schwabe: Pharmacokinetic interactions of topiramate. Clin. Pharmacokinet. 43:763-780 (2004).
E. Perucca, J. French and M. Bialer. Developing novel antiepileptic drugs (AEDs): Challenges, incentives and recent advances. Lancet Neurol., 6:793-804 (2007).
M. Bialer, S.J. Johannessen, H.J. Kupferberg, R.H. Levy, E. Perucca and T. Tomson: Progress report on new antiepileptic drugs: A summary of the Eight Eilat Conference (EILAT VIII). Epilepsy Res.73:1-52 (2007).
M. Bialer. Generic products of antiepileptic drugs (AEDs): Is it an issue? Epilepsia, 48:1825-1832 (2007).
M. Bialer, H. S. White. Key factors in the discovery and development of new antiepileptic drugs (AEDs). Nature Rev. Drug Discov. 9: 68-83 (2010).
H. S. White, A. B. Alex, A. Pollock, N. Hen, T. Shekh-Ahmed, K. S. Wilcox, J. H. McDonough, J. P. Stables, D. Kaufmann, B. Yagen, B. Bialer. A new derivative of valproic acid amide possesses a broad-spectrum antiseizure profile and unique activity against status epilepticus and organophosphate neuronal damage. Epilepsia 53:134-146 (2012)
M. Bialer. Chemical properties of antiepileptic drugs (AEDs). Adv. Drug Deliv. Rev. 64: 887-895 (2012).
M. Bialer, P. Soares-da-Silva. Pharmacokinetics and drug interactions of eslicarbazepine acetate. Epilepsia.53: 935-946 (2012).
M. Bialer, E. Perucca. Does Cannabidiol Have Antiseizure Activity Independent of its Interactions with Clobazam? An Appraisal of the Evidence from Randomized Controlled Trials. Epilepsia, 61: 1082-1089 (2020)
R. Odi, D. Bibi, T. Wager, M. Bialer. A Perspective into the physicochemical and biopharmaceutic properties of marketed antiepileptic drugs - from phenobarbital to cenobamate and beyond. Epilepsia, 61:1543-1552 (2020).
R. Odi, V. Franco, E. Perucca, M. Bialer. A perspective on bioequivalence and switchability of generic AED products. Epilepsia 62: 285-302 (2021).
R. Odi, R.W. Invernizzi, T. Gallily, E. Perucca, M. Bialer. Fenfluramine repurposing from weight loss to epilepsy; what we do and do not know. Pharmacol Ther.226, 107866 (2021).
M. Bilaer, E. Perucca. Lorcaserin for Dravet Syndrome- A potential advance over fenfluramine? CNS Drugs, 21:115-122 (2022).
References
University of Florida alumni
Academic staff of the Hebrew University of Jerusalem
Pharmacologists
People from Petah Tikva
1948 births
Living people
Hebrew University of Jerusalem alumni
University of Kentucky alumni
Israeli biochemists | Meir Bialer | [
"Chemistry"
] | 1,604 | [
"Pharmacology",
"Biochemists",
"Pharmacologists"
] |
70,693,925 | https://en.wikipedia.org/wiki/Stein%20Aerts | Stein Aerts is a Belgian bio-engineer and computational biologist. He leads the Laboratory of Computational Biology at VIB and KU Leuven (University of Leuven), and is director of VIB.AI, the VIB Center for AI & Computational Biology. He has received several accolades for his research into the workings of the genomic regulatory code.
Early life and education
Aerts was born and raised in Heusden-Zolder, Belgium, where he completed his secondary education at Heilig-Hart College. He obtained a Master's degree in Bioscience Engineering (Molecular Biology) from the University of Leuven, and subsequently combined a job as Assistant IT Project Leader at Janssen Pharmaceutica with advanced studies in Applied Computer Science at the University of Brussels. He obtained a PhD in Engineering (Bioinformatics), working at the Department of Electrical Engineering ESAT-SCD at the University of Leuven.
Academic career
Aerts completed his postdoc training working on the genomics of gene regulation in the fruit fly model Drosophila melanogaster in the lab of Bassem Hassan at VIB in Leuven, including a research visit at the Developmental Biology Institute of Marseille, Luminy (IBDML), in France, with Denis Thierry and Carl Herrmann.
In 2009, Aerts was appointed assistant professor at the University of Leuven, where he is now full professor, and heads the Laboratory of Computational Biology at the KU Leuven Department of Human Genetics. Since 2016, he was also appointed VIB group leader. Aerts teaches several courses, including Introduction to Bioinformatics, Bioinformatics: Structural and Comparative Genomics, Bioinformatics and Systems Biology: Sequence, Structure & Evolution and Bioinformatics and Systems Biology: Expression, Regulation and Networks at the University of Leuven. His research focuses on deciphering the genomic regulatory code, using a combination of single-cell, machine-learning, and high-throughput experimental approaches.
Research
Aerts research interest in regulatory genomics and gene regulatory networks cover a wide range of experimental and computational approaches, applied in the context of neuronal development, neurodegeneration, as well as cancer.
During his PhD research, Aerts invented one of the first bioinformatics algorithms for the prediction of genomic enhancers (ModuleSearcher) and developed several bioinformatics tools for the analysis of cis-regulatory sequences (TOUCAN) and for gene prioritisation (Endeavour). Other scientific contributions include new bioinformatics methods for the analysis of single-cell gene regulatory networks, namely iRegulon, SCENIC and cisTopic; a new experimental technique for massively parallel enhancer reporter assays (CHEQ-seq); and a deep learning implementation for enhancer modelling (DeepMEL and DeepFlyBrain).
Aerts co-founded the Fly Cell Atlas consortium and generated a single-cell atlas of the ageing Drosophila brain. In 2022, the consortium announced the completion of a single-nucleus transcriptomic atlas of the adult fruit fly, which they hope will serve as a valuable resource for the research community and as a reference for studies of gene function at single-cell resolution.
The generation of cell and tissue atlases help research to study biological processes, not only in flies but also for modeling human diseases at a whole-organism level with cell-type resolution. Aerts is also part of a pan-European research consortium called LifeTime, which aims to track, understand and target human cells during the onset and progression of complex diseases, and to analyse their response to therapy at single-cell resolution.
Outreach
As an advocate for open science, Aerts deposits the data and methods developed by his team on open repositories, or makes them freely available as open source software and databases.
MendelCraft, a MineCraft mod developed by the Aerts lab, is a video game designed to teach children about DNA, genetics, and the laws of Mendel, by allowing them to cross and clone different breeds of virtual chickens.
Awards
ERC Advanced Grant 2023
Elected EMBO member 2022
Francqui Chair at ULB 2022
ERC Consolidator Grant
2017 Prize for Bioinformatics and Computational Science from the Biotech Fund
2016 Astrazeneca Foundation Award Bioinformatics
References
Living people
Year of birth missing (living people)
Biotechnologists
Computational biologists
KU Leuven alumni
People from Heusden-Zolder
Janssen Pharmaceutica people
Vrije Universiteit Brussel alumni
Academic staff of KU Leuven
Belgian molecular biologists | Stein Aerts | [
"Biology"
] | 953 | [
"Biotechnologists"
] |
70,694,306 | https://en.wikipedia.org/wiki/Reduction-sensitive%20nanoparticles | Reduction-sensitive nanoparticles (RSNP) consist of nanocarriers that are chemically responsive to reduction. Drug delivery systems using RSNP can be loaded with different drugs that are designed to be released within a concentrated reducing environment, such as the tumor-targeted microenvironment. Reduction-Sensitive Nanoparticles provide an efficient method of targeted drug delivery for the improved controlled release of medication within localized areas of the body.
Redox sensitive nanoparticles vs. reduction sensitive nanoparticles
Nanoparticles are small in size with maximized surface area and have an enhanced level of solubility; these elements result in an improved bioavailability. Reduction-Sensitive Nanoparticles are nanoparticles that are responsive to reduction signaling environments. Redox-Sensitive Nanoparticles can be responsive to signaling through a reduction activation or an oxidative activation. Therefore, degradation of chemical bonds can be either activated through oxidants or reductants in the localized area. The cleavage/degradation of chemical bonds will enable the drugs loaded within the nanoparticle to be released into the body. Depending on the activation mechanism, Redox-Sensitive Nanoparticles can be associated with Reduction-Sensitive Nanoparticles if the chemical activation method is through reduction.
Nanoparticle drug loading
Nanoparticle Drug Loading is dependent on the mass ratio of the drug being loaded and the drug-loaded nanoparticle. Variations necessary to consider are the pore volume size, the surface, shape, and charge of the nanoparticle. The mode of drug loading will depend on the type of drug being administered, which will vary depending on the illness that is treated.
Drug Release
One of the limitations of nanoparticles for drug delivery is the insufficient or slow release of drugs. The rate of release is a critical element to identify how slowed drug release could limit the proper concentration of treatment. If the drug is not administered in concentrations high enough it could result in undertreatment of tumor cells with little to no effect. Concentration thresholds must be met to initiate cell death amongst tumor cells. However, the uncontrolled release of treatment could also permit adverse side effects. RSNPs have improved rates of drug release which improves the medication concentrations that can be administered to a specific area.
RSNPs consist of reduction or redox-sensitive bonds. After administration in the body, the RSNP will eventually come into contact with the tumor microenvironment (TME). Nanoparticles can be synthesized to activate when exposed to selective characteristics of the tumor microenvironments. TMEs depict unique characteristics that create a differing microenvironment in comparison to healthy tissue. Thus, nanoparticles can be designed to react to the unique elements of TMEs such as the formation of a reducing environment. The reducing abilities of the TMEs are due to the expression of reducing agents. RSNPs are formulated to express reduction-sensitive bonds that are cleaved when exposed to reducing agents. After the reduction occurs the degradation of the nanoparticles commences and the loaded drugs begin to release.
Physicochemical characterization
RSNPs
The physicochemical characteristics of nanoparticles are inclusive of the size, shape, chemical composition, stability, topography, surface charge, and surface area. Deviations of these characteristics can be impacted by the classification of the nanoparticle. For example, the RSNP can be classified as a polymeric, micelle, or lipid-polymeric hybrid. The reduction sensitivity of nanoparticles is reliant on the reduction-responsive chemical structures infused into the nanoparticle. Reduction occurs when the number of electrons increases in a chemical species. Reduction sensitive nanoparticles depict high plasma stability and quick responsiveness/activation. The reducing environment of tumor cells is greatly impacted by the oxidation and reduction states of NADPH/NADP+ and Glutathione.
Tumor microenvironment
For the effective application of RSNPs, the physicochemical characteristics of the tumor microenvironment must also be considered. The characteristics depicted by the TME are tumor hypoxia, angiogenesis, metabolism, acidosis, reactive oxygen species (ROS), etc. The elements of the tumor microenvironment can affect the reduction-inducing environment. Tumor cells abnormally regulate redox homeostasis leading to differences in the redox balance and increases in ROS levels. Research trends have shown that increased levels of ROS are correlated with high levels of antioxidant activity, such as intracellular GSH.
Reducing agents
Glutathione (GSH) or γ-glutamyl-cysteinyl-glycine is a critical biological reducing agent for drug delivery applications; it creates an effective reducing environment in the cytosol and nucleus of a cell. Glutathione is an antioxidant that is naturally produced in the liver and takes part in tissue building, tissue repair, immune responses, chemical production, and protein production. GSH is also a significant signaler of cell differentiation, proliferation, apoptosis, and ferroptosis. Furthermore, the glutathione concentration in the tumor microenvironment is reportedly at least four times higher compared to regular tissue. This is due to the high metabolic needs of tumor cells; for example, the rapid proliferation rates of tumor cells.
The over-expression of nicotinamide adenine dinucleotide phosphate NADPH can lead to higher ROS levels. NADPH has a lower concentration than GSH in the reducing environment. NADPH is an electron donor that exists among all organisms; additionally, the NADPH is used as a source of reduction to drive anabolic reactions and redox balances. The reduction and oxidation states of NADPH/NADP+ will influence the reduced responsiveness of the environment. Cancer cells express a unique NADPH homeostasis due to the adaptive alterations of signaling pathways and metabolic enzymes.
Subtypes
Reduction sensitive bonds
Disulfide bonds
Redox-Sensitive Nanoparticles with Disulfide bonds are commonly observed in medical research. RSNP can consist of disulfide bonds that are cleaved and introduced to a reduction condition. Additionally, the reduction of glutathione results in the formation of sulfhydryl groups. In large concentrations of GSH, the disulfide bonds are capable of being cleaved. Following the activation process, the degradation of the drug carrier results in the drug release. These linkages are commonly used between hydrophilic and hydrophobic segments in copolymers. Moreover, RSNP's hydrophilic shells will degrade in response to the reducing environment. The disulfide bonds are used as linkers and cross-linking agents. Disulfide bonds can be expressed attached to the side chains, the backbone, on the surface, and as linkages between moieties.
Disulfide bonds can also act as cross-linking agents in micelles nanoparticles. Micelles lack the structural stability as a nanocarrier for drug delivery. The lack of stability can result in the loss of drugs after administration and before reaching the infected area. This occurrence can potentially cause adverse side effects from the improper release of medication. Disulfide bonds can be used as crosslinked structures to increase the structural stability of micelle nanocarriers. In general, these crosslinks are located in the shell or the core of micelles nanoparticles.
Diselenide bonds
Redox-Sensitive Nanoparticles with Diselenide bonds share comparable reduction responsiveness to disulfide bonds. Diselenide consists of two selenium atoms along with an additional element or radical. Diselenide bonds are dynamic covalent bonds that can be exchange between molecules. Diselenide bonds have an estimated bond energy of 172 kJ/mol, and disulfide bonds have estimated bond energy of 268 kJ/mol; the lower bond energy holds a higher potential to design an increased sensitive redox-responsive delivery. Diselenide bonds have been observed to be attached to hydrophobic parts of amphiphilic triblocks or hyperbranched copolymers to create micelles.
Succinimide-thioether bonds
Succinimide-thioether linkages express sensitivity to reducing environments and can be cleaved as a result. Succinimide-thioether bonds show slower rates of release in comparison to disulfide bonds; however, succinimide-thioether nanoparticles are still sensitive to the reducing environment and are cleaved by GSH for fast intracellular release.
Trimethyl benzoquinone bonds
Nanoparticles with Trimethyl Benzoquinone have demonstrated responsiveness to reduced environments. The experiments that have been conducted testing TMBQ are limited in observing the full scope of TMBQ nanoparticles in delivery systems.
Development/Synthesis
The synthesis of reduction sensitive nanoparticles is dependent on the mechanism subtype of the nanoparticle. Additionally, the synthesis can vary within subtype classes depending on how the different reduction sensitive bonds are expressed. The deviations of RSNPs can range from attachments to the backbone, side chains, on the surface, etc. Research has been conducted with reduction sensitivity mechanisms using polymeric, lipid-polymer hybrids, and micelles nanoparticles. The production methods would be dependent on the delivery method design for the nanoparticle. Polymeric nanoparticle synthesis occurs from the addition of electrolyte-saturated or a nonelectrolyte-saturated solution with a water-miscible solvent; additionally, the mixture should be constantly stirred. Lipid micelles are formed by amphiphilic molecules through self-assembly. Lipid-polymer hybrids have multiple synthesis methods which consist of the single-step method, the two-step method, nanoprecipitation, emulsification-solvent evaporation, and a non-conventional two-step method.
Advantages
Reduction Sensitive Nanoparticles provide a mode of localized drug delivery by targeting elements of the tumor microenvironment. RSNP has the advantages of high stability when adhering to hydraulic degradation, fast responsiveness to the intracellular reducing environment, and drug release occurs in the cytosol and cell nucleus. Furthermore, drug release in the cytosol and cell nucleus has shown the potential to effectively administer treatment of more potent and poorly soluble anticancer drugs. The quick-release of RSNPs has the potential to offer an effective treatment for multidrug-resistant tumors. This addresses an important limitation of nanoparticles. Nanoparticle drug delivery often exhibits slow drug release. The slow release can lead the nanomedicine to be released at low concentrations; moreover, these limited concentrations inhibit the cell death of the tumor cells. Polymeric RSNPs have shown improved solubility, stability, biocompatibility, and decreased drug toxicity; for example, carbohydrate polymers.
Limitations
The effectiveness of reduction-sensitive nanoparticles is dependent on the responsiveness of the RSNP throughout the body. The microtumor and inflammatory environments contain higher concentrations of reducing agents in contrast to healthy cells; however, healthy cells still express GSH and NADPH. RSNPs are designed to be receptive to higher concentrations of reducing agents for the ability to distinguish between cancer cells and healthy cells. Furthermore, the other limitations are dependent on other characterizations, such as the type of nanoparticle; For example, micelles nanoparticles' lower levels of physical stability which can lead to drug loss and release in unwanted locations. Additionally, polymeric nanoparticles cannot effectively target the tumor and often undergo drug release too early.
Applications
Tumor/cancer treatments
Reduction Sensitive Nanoparticles are used as nanomedicines for drug delivery. As nanocarriers, RSNP can be loaded with drugs for disease therapeutics. This is commonly observed in the use of tumor and cancer treatments. Cancer cells create reducing environments that are used for RSNP activation. RSNPS can also increase the penetration of cancer treatment to the cancer cells. Specific applications include, but are not limited to Breast Cancer, Liver Cancer (hepatoma), Melanoma, Lung Cancer, Malignant Glioma, Ovarian Cancer, Cervical Cancer, Subcutaneous EAT, Pancreatic Cancer, Colon Cancer, Prostate Cancer, etc.
Inflammatory diseases
The development of RSNP for inflammatory diseases has been explored to a lesser extent. Regardless, in more recent years reduction-sensitive and redox-sensitive nanoparticles have gained more momentum in the realm of inflammatory diseases. Further advances have demonstrated Research has been conducted to evaluate the potential of RSNP as a therapeutic for inflammatory bowel disease. The activation mechanism consisted of pH and redox sensitivity. The outcomes of the experiment demonstrated higher selectivity to the reducing potential; therefore establishing the promising potential of RSNPs for the treatment of inflammatory bowel disease. Other studies have demonstrated potential applications as activatable magnetic resonance contrast agents. These proposed agents would help detect and monitor the treatment of inflammatory diseases by applying redox dysregulation.
References
Nanoparticles by physical property
Drug delivery devices | Reduction-sensitive nanoparticles | [
"Chemistry"
] | 2,756 | [
"Pharmacology",
"Drug delivery devices"
] |
70,694,579 | https://en.wikipedia.org/wiki/Geastrum%20huneckii | Geastrum huneckii is a species of earthstar fungus in the family Geastraceae. Found in Mongolia, it was formally described as a new species in 1981 by German mycologist Heinrich Dörfelt. The species epithet honours his colleague Siegfried Huneck. Characteristics of the fungus include its hygroscopic exoperidium with four rays, a white endoperidium with a well-delimited peristome, and basidiospores measuring 5.5–6.5 μm in diameter.
References
huneckii
Fungi described in 1981
Fungi of Asia
Fungus species | Geastrum huneckii | [
"Biology"
] | 123 | [
"Fungi",
"Fungus species"
] |
70,694,820 | https://en.wikipedia.org/wiki/Dimethoxytrityl | Dimethoxytrityl, often abbreviated DMT, is a protecting group widely used for protection of the 5'-hydroxy group in nucleosides, particularly in oligonucleotide synthesis.
It is usually bound to a molecule, but can exist as a stable cation in solution, where it appears bright orange.
References
Protecting groups | Dimethoxytrityl | [
"Chemistry"
] | 73 | [
"Protecting groups",
"Functional groups",
"Reagents for organic chemistry"
] |
70,694,899 | https://en.wikipedia.org/wiki/Frederick%20S.%20Holmes | Frederick S. Holmes was an American safe and vault engineer, and inventor who designed the largest vaults in the world. During his career, Holmes designed over 200 vaults throughout the United States, Canada and Japan from 1895 to 1941. The majority of Holmes designed vaults are located in New York's Financial District; many are publicly accessible and in buildings on the National Register of Historic Places. His name is engraved on the builder's plaques, typically located on the vault door's encased jamb controls.
Holmes' vault designs evolved over time to keep up with attacks from safe-crackers or 'Yeggmen' adept at vault penetration. A Holmes advertisement from 1921 reads, "Newly discovered methods of attack necessitate radical departures from hitherto accepted standards of design". Holmes specialized in jamb-controlled vaults where the combination locks and bolt-throwing mechanism are located inside the vault creating a solid vault door with no spindle holes. Entry requires two points of attack (door and jamb), which doubles the time required for burglars to breach the vault.
Holmes was an expert in his field and described as 'one of the leading, if not the leading vault engineer of America, and a man whose word is unquestioned by those who have had transactions with him'. In recognition of significant contributions to the field of bank vault engineering, a tribute was written in The Journal of the Franklin Institute stating, “Coincident with the modern development of the safe and bank vault industry was that of the profession of the Bank Vault Engineer. The industry owes much of its progress to the work done by the pioneers of this profession: William H. Hollar, John M. Mossman, George L. Damon, Emil A. Strauss, Frederick S. Holmes, Benjamin F. Tripp, and George L. Remington.” Holmes is known to have collaborated with all these vault engineering greats except for Strauss.
Holmes collaborated with prominent architects such as Cass Gilbert and Alfred Bossom and leading vault builders including Bethlehem Steel, Carnegie Steel, Damon Safe & Iron Works, Diebold, Herring-Hall-Marvin, J&J Taylor, LH Miller Safe & Iron Works, Mosler Safe, Remington & Sherman, and York Safe & Lock.
Early life
Frederick Stacy Holmes was born on August 27th, 1865 in Boston, MA to George W. Holmes and Frances A. Stacy. His father was from Maine and worked as a Pattern Maker and his mother was from New Hampshire and was a housewife. Holmes attended Boston High School and received private engineering instruction in New Hampshire.
Career
Homes first worked as a Pattern Maker like his father, a Machinist and then a Mechanical Draftsman. He worked his way up to General Superintendent for safe and vault manufacturers in Chicago, Boston, and Philadelphia before venturing out on his own. Holmes was co-owner of Hoyer & Holmes with Isaiah Wellington Hoyer in Philadelphia that specialized in safe and vault design and construction. He worked as a Bank Vault Engineer for John M. Mossman from 1900-1904 where he designed the Maiden Lane Safe Deposit Company vault among others. Frederick S. Holmes started his company of the same name in 1901 and by 1910 was designing jamb-controlled vaults for which he was known. He was in private practice for 40 years where he designed his most notable vaults: Federal Reserve Bank of Cleveland, Federal Reserve Bank of New York, One King West Hotel & Residence in Toronto, and Sun Life Insurance in Montreal.
Personal life
Frederick S. Holmes married Katherine E. Vincent from New Hampshire on March 27th, 1886 in Chelsea, MA. He was involved with industry groups such as the American Society of Mechanical Engineers (1913-1930), the Bankers Club (1920-1930), the Investigating Committee of Architects & Engineers (1926), the Engineers’ Club (1920-1930), the Hardware Club of New York (1914), and the New York State Society of Professional Engineers (1936). Holmes had an active social life with membership in the American Club in Toronto (1920), the Brotherhood of Man (1924), the New York Athletic Club (1914-1941), and the Saint Nicholas Society of the City of New York (1920-1930). His political affiliations changed throughout his life; he was a registered Republican (1914-1930) and Independent (1924, 1926, 1931-1932). In 1932, Holmes was critically injured when struck by an automobile while walking home. He was 67 years old at the time and suffered a fractured skull from the hit-and-run driver. Holmes recovered and managed to work another nine years before retiring in 1941 at the age of 76. He died eight years later from arteriosclerotic heart disease on November 10th, 1948 in Hathorne, MA at the age of 84 and was buried at Exeter Cemetery in New Hampshire.
Published works
This list includes articles, copyrights, court testimony, interviews, patents, and speeches by Frederick S. Holmes in chronological order.
References
External links
Holmes Advertisements
Holmes Biographical Info
Jamb-Controlled Vault Evolution
19th-century American inventors
Banking
Federal Reserve Bank buildings
Financial District, Manhattan
Locks (security device)
Mechanical engineering
Security engineering
20th-century American inventors | Frederick S. Holmes | [
"Physics",
"Engineering"
] | 1,053 | [
"Systems engineering",
"Security engineering",
"Applied and interdisciplinary physics",
"Mechanical engineering"
] |
70,695,227 | https://en.wikipedia.org/wiki/Carbomyces%20emergens | Carbomyces emergens is a desert truffle in the genus Carbomyces, a small genus common to the Chihuahuan desert in the southwestern United States and Mexico. C. emergens is regarded as the most common and widely distributed species in Carbomyces, also serving as the genus' type species. C. emergens belongs to the Carbomycetaceae family, in the order Pezizales, class Pezizomycetes, division Ascomycota.
Naming and history
The name Carbomyces emergens comes from Latin and Greek root words. For the genus, carbo from Latin meaning “carbon” and -myces from Greek meaning “fungus” gives the literal name “carbonized fungus”. This is in reference to the original author of the species, Helen Margaret Gilkey, who described the dried periderm of the fungus as having a “texture somewhat that of carbonized wood”. The specific epithet emergens comes from Latin and means emerging. This name describes the way that the fungus emerges at the Earth's surface during maturity.
Carbomyces emergens, one of only three species in the Carbomyces genus, was first discovered in Carlsbad, New Mexico by Helen Margaret Gilkey in 1954. Gilkey originally placed Carbomyces in the family Terfeziaceae. However, species in Carbomyces have fertile tissues separated into pockets by sterile veins that are markedly different than other species in Terfeziaceae. This led to Carbomyces being placed in its own family, Carbomycetaceae in 1971 by J.M. Trappe. This family has since been widely accepted by several authors. In 2001, Trappe & Weber described C. emergens in detail.
In the same paper, Trappe & Weber transferred a previously misplaced species from Abstoma to Carbomyces. The species was originally Abstoma longii, and would’ve been renamed Carbomyces longii, but this epithet was already used within Carbomyces, so it was named C. gilbertsonii instead. Carbomyces has been determined to be related to Terfezia and Kalaharituber.
Description and morphology
Carbomyces emergens is a hypogeous desert truffle. The term desert truffle refers to several edible fungi that grow either entirely under the surface of the earth, or partially covered by it. Many are dispersed primarily dispersed by animals. C. emergens is white to cream in color or yellow to brownish orange, with an occasionally cracked, glaucous surface. The fruiting body is 5-30mm x 8-40mm in size. The fungus has only been found loose on sand or dirt, indicating that the fruiting body emerges at maturity and is released.
On a microscopic level, C. emergens has a two-layered peridium with the texture of carbonized wood. The fungus is found as with a gleba of large, thin-walled hyphae, which disintegrates at maturity to form a powdery spore mass. It has brown-walled, nonamyloid asci, sub-globose to globose in shape. Each ascus contains eight clustered ascospores, which are globose or ellipsoid, smooth or minutely roughened, or verrucose. C. emergens has “nest-like” areas with asci, separated with sterile veins. The ascomata is hypogeous, is found singularly or in clusters, and has regular to compressed or turbinate stereothecia.
Distribution and habitat
Carbomyces emergens is endemic to desert habitats. It's been found across the southwestern United States, from New Mexico to southern California, in the Chihuahuan desert. It has also recently been found in Mexico in the central Chihuahuan desert. However, most of the world remains unexplored for hypogeous fungi, so this range being even more extensive is highly probable.
Carbomyces emergens has been found on arid lands, in xeric conditions, on sandy soils, sand hills and dunes. Every collection occurrence of C. emergens indicates that the fungus is only found lying loose on soil where it is then windblown into arroyos, brush patches, and the like. It has been documented in close range to Artemisia, Atriplex, Prosopis, and various herbaceous species.
Life cycle and ecology
Not much is known of the ecology of Carbomyces species. C. emergens has been found to appear from September to April. The truffles are thought to emerge at maturity and dry in the desert sun and dry air. The glebal cells, which are thin-walled and inflated, disintegrate to form a powdery mass containing spores, asci, and cell fragments. Ecologically, C. emergens has been thought to use animal mycophagy as its primary spore dispersal strategy. It is often eaten by rodents, especially the spotted ground squirrel.
Many desert truffles form mycorrhizal associations with annual or perennial plants, but C. emergens has only been found as arbuscular mycorrhizae. C. emergens likely forms mycorrhizal associations with desert shrubs or trees, such as Cistaceae. While there is not much information about the associations that it forms, C. emergens is thought to mainly form ectomycorrhizal associations with perennial hosts.
References
Pezizales
Truffles (fungi)
Fungi of North America
Fungus species | Carbomyces emergens | [
"Biology"
] | 1,165 | [
"Fungi",
"Fungus species"
] |
70,696,070 | https://en.wikipedia.org/wiki/Local%20Volume | The Local Volume is a collection of more than 500 galaxies located in an area of the observable universe near us, within a spherical region with a radius of 11 megaparsecs from Earth or up to a radial velocity of redshift of z < 0.002 (550 km/s).
It was in this region of the universe where the Local Volume Legacy (LVL) project took place for the study of 258 galaxies through cycles of observations made by the Spitzer Space Telescope using the Infrared Array Camera (IRAC) and the Multiband Imaging Photometer (MIPS).
This Local Volume study included all galaxies within a 3.5 megaparsec subvolume and a collection of spiral and irregular galaxies within 11 megaparsecs. The goals of the study were to collect data on the rate of star formation, stellar mass in old star populations, cosmic dust, and starlight interference.
We can also define the Local Volume by the distance of 10 Mpc over which the Hubble Space Telescope can distinguish stellar populations in galaxies. This definition can be extended to 15 Mpc to cover a full range of galaxy environments, from voids to clusters and massive clusters. In the future, it should be possible to extend our definition of Local Volume to even greater distances.
Within the Local Volume is the Local Sheet, an area of flattened space containing about 60 galaxies that share the same velocity and is about 7 megaparsecs in radius and about 0.5 megaparsecs thick. The Local Group, of which the Milky Way and the Andromeda galaxy are part, is part of the Local Sheet and therefore, of the Local Volume. The Local Volume, in turn, is included in the Laniakea Supercluster.
Local Volume galaxies have a preferred movement called virgocentric flow, towards the Virgo cluster, caused by its overwhelming gravity.
Among the member galaxies of the Local Volume, there are several large galaxies or particular galaxies such as Centaurus A, the Bode galaxy (M81), the Cigar galaxy (M82), the Circinus galaxy, the Southern Pinwheel galaxy (M83), the Pinwheel galaxy (M101), the Sombrero Galaxy (M104), NGC 1512, M51, M74, M66 and M96.
Recently, following Hubble Space Telescope observations, two dwarf galaxies, Pisces A and Pisces B, have been identified as having migrated into the Local Volume from the neighboring Local Void.
See also
Laniakea Supercluster
Pisces–Cetus Supercluster Complex
Observable universe
References
External links
Local Volume Legacy Survey Institute of Astronomy
How Far Away Is It - 12 - The Local Galaxy Volume (1080p) - YouTube
Observational astronomy
Galaxies | Local Volume | [
"Astronomy"
] | 580 | [
"Galaxies",
"Astronomical objects",
"Observational astronomy",
"Astronomical sub-disciplines"
] |
70,697,300 | https://en.wikipedia.org/wiki/Nestor-Guillermo%20progeria%20syndrome | Nestor-Guillermo progeria syndrome is an extremely rare novel genetic disorder that is part of a group of syndromes called progeria. This disorder is characterized by the same symptoms of other progeria syndromes, which are premature aging with accompanying aged physical appearance, osteolysis, osteoporosis, scoliosis and lipoatrophy, however, what makes this disorder unique from other progeroid syndromes is the absence of any atherosclerotic, cardiovascular, and metabolic symptoms/complications, this makes the life-span of a person with NGPS somewhat longer than the average life-span of someone with progeria itself, although in place of the complications mentioned above, there's also additional symptoms, such as joint stiffness, growth retardation, facial dysmorphisms, wide cranial sutures, micrognathia, atrophic skin and a high risk of developing severe skeletal abnormalities
This syndrome is caused by mutations in the BANF1 gene, in chromosome 11q13.1, and is inherited in an autosomal recessive pattern
Discovery
This rare disorder was discovered when 2 seemingly healthy twin boys named Nestor and Guillermo were born in Spain, starting at the age of 2, they rapidly started aging, when they were 10 years old, they had lost their hair, their skin started wrinkling, their bones started weaking and their stature barely increased, it was clear they had progeria; however, their doctors couldn't find what type of progeria they had, since they didn't present cardiovascular abnormalities and they didn't have the known genetic mutations of the mentioned progeroid syndromes, that's when their shared genetic mutations (BANF1) were discovered, and with that discovery came the revelation of a novel progeroid syndrome, by 2011, they were already 20–30 years old.
References
Progeroid syndromes
Autosomal recessive disorders | Nestor-Guillermo progeria syndrome | [
"Biology"
] | 399 | [
"Senescence",
"Progeroid syndromes"
] |
70,698,043 | https://en.wikipedia.org/wiki/Gracilaria%20parvispora | Gracilaria parvispora, also known by the common names long ogo, red ogo, or simply ogo, is a large species of marine red alga in the genus Gracilaria, endemic to Hawaii. It is highly sought after as an edible seaweed and is popular in mariculture and the marine aquarium trade. Also known as limu ogo in Hawaiian.
Description
Gracilaria parvispora is composed of pointed, cylindrical branches, in diameter, extending from a central axis, in diameter, with a single holdfast. Individuals reach lengths upwards of . As with other species of Gracilaria, Gracilaria parvispora can be highly variable based on environmental conditions. Though generally red in coloration, it may also be yellow, brown, green, white, and black depending on sunlight, water flow, and depth. The branching of the central axis is also variable, with individuals generally, though not always, displaying three orders of branching and lower water flow and salinity bringing out denser branch growth.
Large, thick-walled medullary cells grade down to in diameter, giving way to a subcortex 1-2 cells thick and a 1-layered cortex in this species. Tetrasporangia () are scattered and often pear-shaped. Spermatangia take the form of dimples with modified surrounding cells. Cystocarps are in diameter and are only partially filled by a small internal spore mass. Gonimoblast tissue is thin-walled. Tubular nutritive cells and lateral and vertical pit connections of the pericarp are conspicuous; the pericarp contents are star-shaped.
Distribution
Natural distribution
Gracilaria parvispora is endemic to Hawaii, with localized distribution around the islands of Oahu and Molokai. It can be found in Kāneʻohe Bay, Ke’ehi Lagoon, One’ula Beach, and ‘Ewa Beach and at Hau’ula, Coconut Island, and the Oceanic Institute of Hawaii Pacific University. Populations of Gracilaria parvispora in Molokai are the result of experimental outplantings of spore-bearing gravel, introduced between 1983 and 1985 east of Kaunakakai.
It is hypothesized that Gracilaria parvispora is native to Asia and was later introduced to Hawaii for cultivation, though there is no actual evidence. Gracilaria parvispora may have also been a narrow endemic to the islands until its range was expanded by aquaculture. Occurrences of Gracilaria bursa-pastoris from Korea and Japan may actually represent a misidentification of Gracilaria parvispora.
Presence in Baja California Sur
Gracilaria parvispora is an introduced species in Baja California Sur and has been found in San Ignacio Lagoon, San Buto, San Juan de la Costa, and La Concha Beach. The alga's current distribution in the eastern Pacific Ocean and its impacts on native biodiversity remain relatively unknown.
Ecology
Gracilaria parvispora inhabits reef flats and areas with sand-coated rocky substrate. It is tolerant of a wide range of environmental conditions, preferring nutrient rich water, moderate to high lighting and current, dKH between 8 and 12, pH between 8.1 and 8.4, water salinity between 1.010 and 1.025 SG, water temperature between , calcium between 390 and 440 ppm, magnesium between 1,200 and 1,400 ppm, phosphate between 0.01 and 0.1 ppm, and nitrate between 1 and 20 ppm.
Under ideal conditions, the alga is a fast grower and rapidly absorbs micronutrients, capable of increasing its biomass by 150% or more in a single month. In fact, it is one of the fastest growing species of Gracilaria and is one of the larger species of red algae native to the Hawaiian Islands. Though once common in the region, the alga has become overharvested, with the invasive Gracilaria salicornia having largely replaced Gracilaria parvispora around the island of Oahu.
Conservation
Alongside Gracilaria coronopifolia and Asparagopsis taxiformis, Gracilaria parvispora is one of the three most highly sought after edible seaweeds in the Hawaiian Islands; there may possibly be an export market for dried Gracilaria parvispora. In Hawaii, it has historically been incorporated into recipes representing Hawaiian, Korean, Filipino, Japanese and Caucasian cuisines, such as poke, or eaten raw.
In the 1930s, Gracilaria parvispora began to be commercially harvested in Oahu and would become the most popular seaweed in Honolulu fish markets up until the 1970s. Since then, overharvesting has made this species increasingly rare in the wild; its limited availability led to the importation and mariculture of Atlantic Gracilaria tikvaheae as a replacement, which differs from Gracilaria parvispora in taste, texture, and appearance. In 1988, the collection of fertile Gracilaria parvispora, with cystocarps, was outlawed.
Mariculture
Mariculture of Gracilaria parvispora has been extensively researched. In 1991, researchers at the University of Arizona experimented on growing Gracilaria parvispora in Hawaiian fishponds along Molokai's south shore. It was successfully maricultured at mean yields of when grown inside floating baskets. Lower water current, at water velocities such as , were found to be desirable. Higher current, at water velocities such as , may encourage undesirable epiphyte growth, including Lyngbya majuscula, Hypnea cervicornis, and Acanthophora spicifera. Growing Gracilaria parvispora attached to lines submerged in Ualapue Pond also yielded high growth rates albeit with poor recovery as the thalli were often severed. Growing Gracilaria parvispora in Ualapue Pond within bottom culture pens resulted in low growth rates due to low light penetration and smothering by silt. Gracilaria parvispora is also difficult to maintain in tank cultures, failing to develop desirable, fine branches (likely due to excessive water flow) and eventually fragmenting into necrotic pieces after several weeks. Resources necessary for water exchange in tank cultures are also prohibitively expensive and energy intensive, including shoreline modifications, a pumping station, and a seawater discharge point.
Nutrition
In 2003, researchers at the University of Hawaiʻi analyzed the nutritional composition of twenty-two edible Hawaiian seaweed species, including Gracilaria parvispora. Fresh Gracilaria parvispora was found to be composed of 90.4 ± 0.1% water. Composition and caloric content of dried, powdered Gracilaria parvispora was found to be 48.1 ± 0.4% ash, 7.6 ± 0.4% total protein, 22.9 ± 0.9% soluble carbohydrate, 2.8 ± 0.3% crude lipid, and for powder. The riboflavin content of dried, powdered Gracilaria parvispora was found to be . The essential mineral element content of dried, powdered Gracilaria parvispora was found to be 1.48% nitrogen, 0.15% phosphorus, 16.00% potassium, 0.49% magnesium, 0.38% calcium, 3.99% sulfur, boron, zinc, manganese, iron, and copper. Like other aquacultured Gracilaria species, Gracilaria parvispora did not have an unusually high nutritional value.
In aquaria
Gracilaria parvispora is a highly functional macroalga in marine aquaria and is the most popular species of Gracilaria in the marine aquarium hobby. It is known to be very hardy, though it should ideally be supplemented with trace elements, such as iron. In addition, Gracilaria parvispora can both be grown attached to substrate or left unattached and gently tumbled to dislodge detritus from its branches. Often, this alga is used in refugia for nutrient export, though it also has applications as a hitching post for seahorses and for display. Due to its rapid growth rate, trimmings of Gracilaria parvispora can be harvested from a refugium and used as a nutritious food source for various herbivorous fish and invertebrates, including tangs, rabbitfish, pygmy angelfish, and blennies. If the alga begins to turn white, the affected thallus should be removed as this is a sign of decomposition.
See also
Edible seaweed
Gracilaria
Limu (algae)
List of marine aquarium plant species
Mariculture
Refugium (fishkeeping)
Seaweed farming
References
External links
iNaturalist
Algae of Hawaii
Edible algae
Edible seaweeds
Endemic fauna of Hawaii
Flora of Northwestern Mexico
Flora of the Pacific
Gracilariales
Hawaiian cuisine
Marine biota of North America
Marine fauna of the Gulf of California
Plants described in 1985
Seaweeds
Species described in 1985
Taxa named by Isabella Abbott | Gracilaria parvispora | [
"Biology"
] | 1,947 | [
"Seaweeds",
"Algae",
"Edible algae"
] |
70,699,065 | https://en.wikipedia.org/wiki/Posovolone | Posovolone (developmental code name Co 134444) is a synthetic neurosteroid which was under development as a sedative/hypnotic medication for the treatment of insomnia.
It is orally active and acts as a GABAA receptor positive allosteric modulator. In animals, posovolone shows anticonvulsant, anxiolytic-like, ataxic, and sleep-promoting effects and appeared to produce effects similar to those of pregnanolone. Development of the agent was started by 1999 and appears to have been discontinued by 2007. In 2021, an was registered for posovolone with the descriptor of "antidepressant". Posovolone was originally developed by Purdue Pharma.
See also
List of investigational antidepressants
List of investigational sleep drugs
List of neurosteroids
References
External links
CO 134444 - AdisInsight
5α-Pregnanes
Sterols
Anticonvulsants
Antidepressants
Anxiolytics
Experimental psychiatric drugs
GABAA receptor positive allosteric modulators
Hypnotics
Imidazoles
Ketones
Neurosteroids
Pregnanes
Sedatives | Posovolone | [
"Chemistry",
"Biology"
] | 249 | [
"Hypnotics",
"Behavior",
"Ketones",
"Functional groups",
"Sleep"
] |
70,699,900 | https://en.wikipedia.org/wiki/Pol.is | Polis (or Pol.is) is wiki survey software designed for large group collaborations. An example of a civic technology, Polis allows people to share their opinions and ideas, and its algorithm is intended to elevate ideas that can facilitate better decision-making, especially when there are lots of participants.
Polis has been credited for assisting the passage of legislation in Taiwan. Pol.is has also been used in America, Canada, Singapore, Philippines, Spain and other governments around the world.
Pol.is was founded by Colin Megill, Christopher Small, and Michael Bjorkegren after the Occupy Wall Street and Arab Spring movements.
In Taiwan, pol.is has been "one of the key parts" of vTaiwan's suite of open-source tools for its citizen engagement efforts arising out of the Sunflower Student Movement. vTaiwan claims that of the 26 national issues related to technology were discussed on the platform and 80% led to government action. Pol.is is also utilized by "Join," a national platform for online deliberation run by the Taiwanese government. Megill credits Audrey Tang and CL Kao, a cofounder of g0v, with convincing him to open-source pol.is.
In 2023, Megill advised OpenAI on how to facilitate deliberation at scale in a way that was more efficient that Polis, which still required significant human labor and analysis at the time. He helped to award $1 million in grants to teams working on solving the problem of deliberation at scale.
Reception
Andrew Leonard, The Financial Times, and VentureBeat describe Pol.is as a possible antidote to the divisiveness of traditional internet discourse by gamifying consensus. Audrey Tang agreed saying, "Polis is quite well known in that it's a kind of social media that instead of polarizing people to drive so called engagement or addiction or attention, it automatically drives bridge making narratives and statements. So only the ideas that speak to both sides or to multiple sides will gain prominence in Polis."
Carl Miller praised the technology as having "gamified finding consensus."
Darshana Narayanan, in an op-ed in the Economist, argues that open-source machine-learning-based tools like Polis can help to bypass the influence of special interests or experts.
Jamie Susskind cited polis and vTaiwan as a model for democracies, particularly around digital policy issues.
See also
Deliberative democracy
Deliberative opinion poll
Habermas machine
Recommender system#Decision-making
Social media#Criticism, debate and controversy
External links
Media coverage of the organization compiled by Pol.is
Can Taiwan Reboot Democracy? by Click (BBC) via YouTube
References
Algorithms
Open source projects
Deliberative groups
Participatory democracy
E-democracy | Pol.is | [
"Mathematics",
"Technology"
] | 575 | [
"E-democracy",
"Applied mathematics",
"Algorithms",
"Mathematical logic",
"Computing and society"
] |
70,699,929 | https://en.wikipedia.org/wiki/Drug-induced%20gingival%20enlargement | Drug-induced gingival enlargement (DIGE), also referred to as drug-induced gingival hyperplasia (DIGH) or drug-induced gingival overgrowth (DIGO), is a side effect of many systemic medications for which the Gingervae are not the target receptor. It is normally resultant of medications including immunoregulators, calcium channel blockers and anticonvulsants. When allowed to progress assisted by routinely poor oral hygiene, DIGE can lead to pain and disfigurement, however there are great variations in its presentation and severity dependent on the case. It is suggested that enlargement is aided by genetic predispositions, tending to occur more frequently in the papillae of the anterior Gingivae in younger age groups.
Class of drugs
The main classes of drugs that result in gingival hyperplasia are as follows.
Anticonvulsants
Anticonvulsant agents, such as phenytoin, are associated with common forms of gingival overgrowth. It is caused by the increase of metabolites from the breakdown of anticonvulsants in the body. It should also be noted that concurrent usage of different anticonvulsants in children has resulted in accumulative gingival enlargement.
Immunosuppressive drugs
Immunoregulators are often prescribed to patients who have organ transplantations and/or some autoimmune diseases. Common immunosuppressive drugs linked to gingival hyperplasia are cyclosporin and tacrolimus.
The most frequently used immunosuppressive drug is cyclosporin, which is commonly prescribed after an organ transplant. Nearly 53% of patients taking cyclosporin after renal transplants presented with gingival growth. Inflammation from bacterial overgrowth in the gingiva and cyclosporin's main metabolite, hydroxycyclosporin, stimulate production of collagen, while simultaneously inhibiting collagen breakdown — leading to a net increase in production of gingival tissues. Tacrolimus, on the other hand, is less toxic than cyclosporin, causing less severe gingival overgrowth, hepatic and renal toxicity.
Management
If gingival overgrowth becomes a legitimate concern, initial management would be proper oral hygiene habits as it is the least invasive option to alleviate overgrowth. Otherwise, it may also be advisable to cease medication, although this should only be done with the patients’ medical practitioners’ consent, and complete resorption may still take up to 8 weeks. In cases where medication cannot be paused, patients’ medical practitioners or consultants should be consulted to discuss treatment options. Replacement drugs may be suggested. For example, vigabatrin may substitute phenytoin as anticonvulsant. However, this method may be ineffective for long-standing overgrowth.
Another option is the surgical removal of excess tissue via gingivectomy. This method is widely successful, although recurrence has been reported for certain drugs. Nonetheless, the procedure is associated with risk of hemorrhage in the highly inflamed and vascularized gingiva. As such, laser or ND:YAG laser has been suggested for accurate, cauterized, and sterilized incisions. Other nonsurgical interventions such as fast mimicking diet regime and nonsurgical periodontal therapy has also been suggested for alleviating gingival overgrowth, thus reducing the need for surgical intervention. However, they could not prevent or fully resolve gingival overgrowth alone.
References
Periodontal disorders
Drug-induced diseases | Drug-induced gingival enlargement | [
"Chemistry"
] | 768 | [
"Drug-induced diseases",
"Drug safety"
] |
70,700,062 | https://en.wikipedia.org/wiki/Maria%20Start | Maria Start (born 14 December 1966) is a British automata maker and restorer. She trained in Fashion design in Maidenhead, Berkshire, and now specialises in the conservation and restoration of antique automata, with a focus on 19th Century automata.
Maria Start is co-founder of "The House of Automata". Together with her husband, Michael Start, they restore and deal in antique automata. Founded in London, it is now based in the North of Scotland, where “The House of Automata” operates from a workshop studio.
Media and television
Maria Start features as an expert on Salvage Hunters- The Restorers, produced by Quest and Discovery Channel. Together with her husband Michael, they appear in Series 3, 4, 5 and 6, as experts in Automata restoration & similar mechanical toys and games.
References
External links
The House of Automata
The House of Automata
The House of Automata - YouTube
Login • Instagram
Salvage Hunters on Quest discovery+ | Stream 55,000+ Real-Life TV Episodes
Michael Start
Automata Convention
1966 births
Living people
Automata (mechanical)
Conservator-restorers
21st-century British women | Maria Start | [
"Engineering"
] | 237 | [
"Automata (mechanical)",
"Automation"
] |
70,700,466 | https://en.wikipedia.org/wiki/H3T45P | H3T45P is an epigenetic modification to the DNA packaging protein histone H3. It is a mark that indicates the phosphorylation the 45th threonine residue of the histone H3 protein.
During apoptosis, H3T45 phosphorylation is required for structural changes inside the nucleosome that enable DNA nicking and/or fragmentation.
The H3T45 residue appears to be a nucleosome gatekeeper, regulating DNA accessibility at transcription target sites. This could be a new regulatory network that coordinates gene expression to enable the necessary cell expansion that comes with cell proliferation. It could be a particularly distinctive target for cancer therapies and as a biomarker.
Phosphorylation of the nucleosome DNA entry-exit region improves access to DNA binding complexes, and the combination of phosphorylation and acetylation has the ability to alter DNA accessibility to transcription regulatory complexes dramatically.
Nomenclature
The name of this modification indicates the protein phosphorylation of threonine 45 on histone H3 protein subunit:
Serine/threonine/tyrosine phosphorylation
The addition of a negatively charged phosphate group can lead to major changes in protein structure, leading to the well-characterized role of phosphorylation in controlling protein function. It is not clear what structural implications histone phosphorylation has, but histone phosphorylation has clear functions as a post-translational modification.
Clinical effect of modification
In vitro and in vivo, the kinase responsible for H3T45ph is protein kinase C-delta. H3T45ph causes structural changes inside the nucleosome to promote DNA nicking and/or fragmentation due to its nucleosomal location.
H3T45 is phosphorylated by a histone kinase complex that includes the conserved S-phase replication start enzyme Cdc7, its activating protein Dbf4, and a number of other components. The H3T45 residue appears to be a nucleosome gatekeeper, regulating DNA accessibility at transcription target sites. This could be a new regulatory network that coordinates gene expression to enable the necessary cell expansion that comes with cell proliferation.
H3T45 phosphorylation promotes H3K56 acetylation. Phosphorylation of the nucleosome DNA entry-exit region improves access to DNA binding complexes, and the combination of phosphorylation and acetylation has the ability to alter DNA accessibility to transcription regulatory complexes dramatically.
Histone modifications
The genomic DNA of eukaryotic cells is wrapped around special protein molecules known as histones. The complexes formed by the looping of the DNA are known as chromatin.
Post-translational modification of histones such as histone phosphorylation has been shown to modify the chromatin structure by changing protein:DNA or protein:protein interactions. Histone post-translational modifications modify the chromatin structure. The most commonly associated histone phosphorylation occurs during cellular responses to DNA damage, when phosphorylated histone H2A separates large chromatin domains around the site of DNA breakage. Researchers investigated whether modifications of histones directly impact RNA polymerase II directed transcription. Researchers choose proteins that are known to modify histones to test their effects on transcription, and found that the stress-induced kinase, MSK1, inhibits RNA synthesis. Inhibition of transcription by MSK1 was most sensitive when the template was in chromatin, since DNA templates not in chromatin were resistant to the effects of MSK1. It was shown that MSK1 phosphorylated histone H2A on serine 1, and mutation of serine 1 to alanine blocked the inhibition of transcription by MSK1. Thus results suggested that the acetylation of histones can stimulate transcription by suppressing an inhibitory phosphorylation by a kinase as MSK1.
Mechanism and function of modification
Phosphorylation introduces a charged and hydrophilic group in the side chain of amino acids, possibly changing a protein's structure by altering interactions with nearby amino acids. Some proteins such as p53 contain multiple phosphorylation sites, facilitating complex, multi-level regulation. Because of the ease with which proteins can be phosphorylated and dephosphorylated, this type of modification is a flexible mechanism for cells to respond to external signals and environmental conditions.
Kinases phosphorylate proteins and phosphatases dephosphorylate proteins. Many enzymes and receptors are switched "on" or "off" by phosphorylation and dephosphorylation. Reversible phosphorylation results in a conformational change in the structure in many enzymes and receptors, causing them to become activated or deactivated. Phosphorylation usually occurs on serine, threonine, tyrosine and histidine residues in eukaryotic proteins. Histidine phosphorylation of eukaryotic proteins appears to be much more frequent than tyrosine phosphorylation. In prokaryotic proteins phosphorylation occurs on the serine, threonine, tyrosine, histidine or arginine or lysine residues. The addition of a phosphate (PO43-) molecule to a non-polar R group of an amino acid residue can turn a hydrophobic portion of a protein into a polar and extremely hydrophilic portion of a molecule. In this way protein dynamics can induce a conformational change in the structure of the protein via long-range allostery with other hydrophobic and hydrophilic residues in the protein.
Epigenetic implications
The post-translational modification of histone tails by either histone-modifying complexes or chromatin remodeling complexes is interpreted by the cell and leads to complex, combinatorial transcriptional output. It is thought that a histone code dictates the expression of genes by a complex interaction between the histones in a particular region. The current understanding and interpretation of histones comes from two large scale projects: ENCODE and the Epigenomic roadmap. The purpose of the epigenomic study was to investigate epigenetic changes across the entire genome. This led to chromatin states, which define genomic regions by grouping different proteins and/or histone modifications together.
Chromatin states were investigated in Drosophila cells by looking at the binding location of proteins in the genome. Use of ChIP-sequencing revealed regions in the genome characterized by different banding. Different developmental stages were profiled in Drosophila as well, an emphasis was placed on histone modification relevance. A look in to the data obtained led to the definition of chromatin states based on histone modifications. Certain modifications were mapped and enrichment was seen to localize in certain genomic regions.
The human genome is annotated with chromatin states. These annotated states can be used as new ways to annotate a genome independently of the underlying genome sequence. This independence from the DNA sequence enforces the epigenetic nature of histone modifications. Chromatin states are also useful in identifying regulatory elements that have no defined sequence, such as enhancers. This additional level of annotation allows for a deeper understanding of cell specific gene regulation.
Methods
The histone mark can be detected in a variety of ways:
1. Chromatin Immunoprecipitation Sequencing (ChIP-sequencing) measures the amount of DNA enrichment once bound to a targeted protein and immunoprecipitated. It results in good optimization and is used in vivo to reveal DNA-protein binding occurring in cells. ChIP-Seq can be used to identify and quantify various DNA fragments for different histone modifications along a genomic region.
2. Micrococcal Nuclease sequencing (MNase-seq) is used to investigate regions that are bound by well-positioned nucleosomes. Use of the micrococcal nuclease enzyme is employed to identify nucleosome positioning. Well-positioned nucleosomes are seen to have enrichment of sequences.
3. Assay for transposase accessible chromatin sequencing (ATAC-seq) is used to look in to regions that are nucleosome free (open chromatin). It uses hyperactive Tn5 transposon to highlight nucleosome localisation.
References
Epigenetics
Post-translational modification | H3T45P | [
"Chemistry"
] | 1,783 | [
"Post-translational modification",
"Gene expression",
"Biochemical reactions"
] |
70,703,174 | https://en.wikipedia.org/wiki/Slick%20%28hiding%20place%29 | A slick (, noun form of the Hebrew root ס-ל-ק, "to remove") is a type of hiding place for weapons. They were used by the militant Zionist groups operating in Mandatory Palestine, including Haganah, Lehi and Irgun. They were built all over the country in order to provide easy access to weapons, which were used to protect settlements and carry out offensive operations.
References
Rooms
Types of secret places | Slick (hiding place) | [
"Engineering"
] | 90 | [
"Rooms",
"Architecture"
] |
70,703,473 | https://en.wikipedia.org/wiki/Robert%20E.%20Ireland | Robert E. Ireland (1929 – February 4, 2012) was an American chemist and the Thomas Jefferson Chair Professor of chemistry at the University of Virginia. He is known for his textbook Organic Synthesis and his contributions to the Ireland–Claisen rearrangement chemical reaction.
Academic career
Ireland earned his A.B. in chemistry in 1951 at Amherst College and earned his Ph.D. in chemistry in 1954 from the University of Wisconsin with William Summer Johnson, and did his postdoctoral work at UCLA with William Gould Young. In 1956, he joined the chemistry department of University of Michigan. In 1965, he became a professor of organic chemistry at the California Institute of Technology. In 1985 he became the director of the Merrell Dow Research Institute in Strasbourg, France. A year later, he became the chair of the chemistry department of University of Virginia.
Awards and honors
Ernest Guenther Award, 1977
Personal life
Ireland was married to wife Margaret and had two sons, Mark and Robert.
References
External links
1929 births
2012 deaths
American organic chemists
Amherst College alumni
University of Wisconsin–Madison alumni
University of Michigan faculty
California Institute of Technology faculty
University of Virginia faculty | Robert E. Ireland | [
"Chemistry"
] | 230 | [
"Organic chemists",
"American organic chemists"
] |
70,704,512 | https://en.wikipedia.org/wiki/Cuphophyllus%20colemannianus | Cuphophyllus colemannianus is a species of agaric (gilled mushroom) in the family Hygrophoraceae. It has been given the recommended English name of toasted waxcap. The species has a European distribution, occurring mainly in agriculturally unimproved grassland. Threats to its habitat have resulted in the species being assessed as globally "vulnerable" on the IUCN Red List of Threatened Species.
Taxonomy
The species was first described from Britain in 1854 by naturalist Andrew Bloxam as Hygrophorus colemannianus. It was transferred to the genus Cuphophyllus by the French mycologist Marcel Bon in 1985.
Recent molecular research, based on cladistic analysis of DNA sequences, has confirmed that Cuphophyllus colemannianus is a distinct species.
Description
Basidiocarps are agaricoid, up to 50mm (5 in) tall, the cap hemispherical at first, becoming broadly convex to flat when expanded, up to 50mm (3 in) across. The cap surface is smooth, slightly greasy when damp, brown with paler margin. The lamellae (gills) are waxy, thick, decurrent (running down the stipe), white to pale buff. The stipe (stem) is smooth, white, lacking a ring. The spore print is white, the spores (under a microscope) smooth, inamyloid, ellipsoid, c. 7.5 to 9 by 5 to 6μm.
Distribution and habitat
The Toasted Waxcap is widespread but generally rare throughout Europe. It is also known from Greenland. Like most other European waxcaps, Cuphophyllus colemannianus occurs in old, agriculturally unimproved, short-sward grassland (pastures and lawns), with a marked preference for calcareous sites.
Recent research suggests waxcaps are neither mycorrhizal nor saprotrophic but may be associated with mosses.
Conservation
Cuphophyllus colemannianus is typical of waxcap grasslands, a declining habitat due to changing agricultural practices. As a result, the species is of global conservation concern and is listed as "vulnerable" on the IUCN Red List of Threatened Species. Cuphophyllus colemannianus also appears on the official or provisional national red lists of threatened fungi in several European countries, including Croatia, Czech Republic, Denmark, Finland, Germany, Norway, and Sweden.
See also
List of fungi by conservation status
References
Fungi of Europe
Hygrophoraceae
Fungi described in 1854
Fungus species | Cuphophyllus colemannianus | [
"Biology"
] | 526 | [
"Fungi",
"Fungus species"
] |
70,704,600 | https://en.wikipedia.org/wiki/Protein%20nanoparticles | Protein nanotechnology is a burgeoning field of research that integrates the diverse physicochemical properties of proteins with nanoscale technology. This field assimilated into pharmaceutical research to give rise to a new classification of nanoparticles termed protein (or protein-based) nanoparticles (PNPs). PNPs garnered significant interest due to their favorable pharmacokinetic properties such as high biocompatibility, biodegradability, and low toxicity Together, these characteristics have the potential to overcome the challenges encountered with synthetic NPs drug delivery strategies. These existing challenges including low bioavailability, a slow excretion rate, high toxicity, and a costly manufacturing process, will open the door to considerable therapeutic advancements within oncology, theranostics, and clinical translational research.
Continued advancement within this field is required for the clinical translation of PNPs. As of 2022, only one PNP formulation (Abraxane) and five VLPs (Gardasil, Ceravix, Mosquirix, Sci-B-Vac, Gardasil9) are approved by the FDA for clinical use. FDA approval of PNPs formulations is restrained by complications arising from in-vivo interactions between PNPs and the biological environment that jeopardize their safety or function. For example, PNPs may undergo protein conformation changes, form a protein corona, or induce inflammation and may risk patient well-being.
Synthesis methods
To capitalize on the favorable characteristics of PNPs, improvements within PNP synthesis methods are being widely explored. Advancements or the development of new synthesis methods are desirable as existing methods (sonochemistry, thermal decomposition, and colloidal/ hydrothermal/microemulsion methods) contribute to systemic toxicity and are limited to hydrophilic drugs. As a result, recent advancements seek to overcome these challenges and achieve commercial-size production.
In addition, newly developed PNP synthesis methods such as electrospray or desolvation provide a more sustainable approach as compared to traditional nanoparticle methods. Unlike synthetic nanoparticles, PNPs can be synthesized under mild conditions and without toxic chemicals or organic solvents. PNPs are also naturally sourced and readily degradable. Yet, despite these advantages and the addition of new synthesis methods, the methods remain relatively expensive and do not deliver full control of PNP size, greatly limiting their application in biomedicine
Types of protein
Numerous proteins are utilized in PNP synthesis. They are often sourced naturally from animal and plant sources. Accordingly, generally shared advantages of animal proteins include high biocompatibility, biodegradability, non-immunogenicity, drug loading efficiency, cell uptake, and easy and cost-effective production. Tables 2–4 below compile the common proteins used in PNP synthesis. The types of PNPs share similar physical properties such as high biocompatibility, non-immunogenicity, high drug efficiency, high biodegradability, and high cell uptake. Due to the abundance of proteins necessary for proper bodily function, the body has developed processes to update proteins into tissues and cells. PNPs take advantage of these natural processes to enhance their cellular uptake. This abundance and the natural sourcing subsequent purification of the proteins also reduce the immunogenic responses and produce low toxicity levels in the body. As the PNPs are degraded, the tissues assimilate the amino acids into energy or protein production.
Protein nanoparticle modifications
PNPs can be chemically modified to increase particle stability, reduce degradation, and enhance favorable characteristics. Crosslinking is a common modification that can utilize synthetic or natural cross-linkers. Natural cross-linkers are significantly less toxic than synthetic cross-linkers.
Driving factors in the modification of PNPs stem from their surface properties (surface charge, hydrophobicity, functional groups, etc.). Functional groups can bind to tissue-specific ligands for targeted drug delivery. Functional ligands may include protein receptors, antibodies, and smaller peptides. The purpose of ligand binding is to direct the PNP to the target cells, thereby reducing systemic toxicity, and improving the retention and excretion of the PNP within tissues. The optimal ligand for PNP modification is dependent on the target cell. Modification of a PNP surface with ligands can be achieved through chemical conjugation, though chemical dyes for imaging and peptides for immune activation can also be attached [11,33,34]. One example is the ligand anti-human epidermal growth factor receptor 2 which targets breast cancer cells. The following provides additional applications of ligand modifications and their therapeutic applications [12].
In addition to chemical conjugation, genetic modification can facilitate direct attachment of the modifying protein monomers with the PNP surface. This results in a co-assembly and a solution to existing challenges with direct attachments or large proteins. Attaching large proteins to PNPs interferes with the self-assembly process and induces steric interactions. Though, smaller protein attachments are generally tolerated by protein NPs. A significant limitation to direct attachment via genetic modification of protein monomers is that it cannot accommodate the attachment of multiple components. Enzymatic ligation helps overcome this limitation by providing a site-specific covalent link to the PNP surface following PNP assembly. This strategy can also provide greater control over the density and ratios of attached proteins.
The modification of VLPs is unique due to their nanocage architecture. PNPs with cage structures can fully encapsulate functional components in their interior, termed co-encapsulation. Drug encapsulation within VLP cages can occur through two processes. This first process occurs in-vitro and requires the disassembly of the cage and reassembling it with the presence of the drug components to be encapsulated [8]. Since loading efficiency is influenced through electrostatic interactions, the drug compounds cannot be fully encapsulated without interfering with the VLP cage self-assembly. Another process is the encapsulation of drug components in-vivo. This involves direct genetic attachment of the drug components to the interior of the VLP cage. This process guides drugs for encapsulation directly to the interior of the cage.
Therapeutic drug delivery applications
Due to PNPs’ breadth of favorable pharmacokinetic properties such as high biocompatibility, high biodegradability, high modifiability, low toxicity, high cell uptake, and a fast excretion rate, PNPs are prime candidates for anti-cancer therapy. Previous anticancer therapies relied on the enhanced permeability effect to passively accumulate within tumors. This resulted in greater toxicity due to higher concentrations required to achieve critical drug efficacy levels. Newer strategies allow PNPs to actively target the tumor microenvironment via the attachment of ligands and site-specific protein receptors. Active targeting decreases the total concentration of drugs required to deliver an effective dose, thereby reducing systemic side effects.
In addition to active tumor targeting, PNPs can also be engineered to respond to changing external environments such as pH, temperature, or enzyme concentration. The tumor microenvironment is slightly acidic, so PNPs can be engineered to only release their drug cargo under specific tumor physiological conditions.
Another application is photothermal or photodynamic therapy. PNPs selectively accumulate into the tumor microenvironment where they are subsequently irradiated using a 1064 nm wavelength laser. The light energy is transferred into heat energy, increasing the temperature of the tumor microenvironment to inhibit tumor growth. Ferritin is a favorable protein for this application due to its high thermal stability.
In-vivo imaging is another application of PNPs. PNPs can carry fluorescent dyes that selectively accumulate in the tumor microenvironment. This is important because a significant limitation of Green Fluorescent Protein, the standard protein for tumor imaging, is its insufficient deep tissue penetration. Due to their small size, PNPs can deliver fluorescent dyes deep into the tissue overcoming this challenge and providing more accurate tumor imaging. This strategy may also be applied to MRI imaging using PNPs carrying magnetic components to tumor microenvironments for subsequent scanning.
Other applications include vaccine development through VLPs carrying immunogenic components. Since VLPs are not carrying any attenuated genetic material, these vaccines pose a safer alternative, especially for the immunocompromised or elderly. PNPs may also treat neurological diseases as they can cross the blood-brain barrier [28]. Lastly. PNPs may find applications within ophthalmic drug delivery as PNPs have a significantly longer circulation time in the eye than eye drops.
Drug delivery challenges and regulations
Despite numerous pharmacokinetic advantages of PNPs, there remain several critical challenges to their clinical translation. Only two PNPs have been FDA-approved, despite over 50 PNP formulations to date (2022). The two FDA-approved drugs include Abraxane, an albumin nanoparticle carrying paclitaxel used for breast cancer, non-small cell lung cancer, and pancreatic cancer treatment. The second FDA-approved PNP is Ontak, a protein conjugate carrying L-2 and Diphtheria toxin used for cutaneous T-cell lymphoma. The two approved formulations are summarized in Table 5 below. The low approval rate of PNPs is due to limited existing control over drug encapsulation and the pharmacokinetic variability between PNP batches. Balancing both the repeatability of these two properties and their relative interactions is important because it ensures the predictability of their clinical outcomes, greater patient safety, and that protein loading does not interfere with the PNP's properties.
Another limitation surrounds the cost and ability of large-scale production. Many synthesis methods that can deliver greater homogeneity between produced nanoparticles are also more costly options or cannot achieve mass production. This limitation is compounded by the lower yields of PNP manufacturing. This limits the availability of PNPs to broad clinical adoption [20,29].
References
Protein complexes
Nanotechnology | Protein nanoparticles | [
"Chemistry",
"Materials_science",
"Engineering"
] | 2,124 | [
"Pharmacology",
"Drug delivery devices",
"Materials science",
"Nanomedicine",
"Nanotechnology"
] |
70,704,752 | https://en.wikipedia.org/wiki/Valley%20View%20Leasing%20and%20Mining%20Company%20Mill | The Valley View Leasing and Mining Company Mill, also known as the Matterhorn Mill, near Ophir, Colorado, is a flotation mill which was built in 1920 and was renovated in 1961. It was listed on the National Register of Historic Places in 2010.
It is in plan and tall.
The mill is located in the valley of the Lake Fork of the San Miguel River at an elevation of 9,431 feet, and at the base of the east slope of 11,845 foot high San Bernardo Mountain in the Trout Lake Mining District just north of Lizard Head Pass. The mill is located approximately 30 degrees from true north, however, the following description refers to nominal directions. Thus, the structure extends roughly 146 feet east to west and 46 feet north to south. At its highest point at the east, the mill is ninety-six feet in height and is visible above the surrounding forest from the highway. To the west, the 146-foot long mill extends down a west slope in five steps to the mill tailings pond located on what was a bench above the Lake Fork of the San Miguel River. The area around the mill is forested, though to the east it is sparse within the 150-foot setback from the highway. Access is by a circular roadway system that connects to the highway north and south of the mill site. The dirt access road leads to the 1960s storage bin of the mill. Beyond is the original grade of the abandoned Rio Grande Southern Railroad spur that extended 200 feet northerly from the Matterhorn Depot across the east elevation of the mill and terminating at the northeast corner according to the 1922 Sanborn Map. The spur passed through a rock cut constructed in 1919 in preparation for the construction of the mill. The Sanborn Map also noted that the mill was electrified, steam heated, and supplied with water from the nearby “creek” that was stored in a 10,000 gallon tank located on the hillside above the mill.
Designated a San Miguel County Landmark December 16, 2005, the Matterhorn Mill was typical of the first generation of flotation mills used to concentrate ores prior to shipment to distant smelters for final processing. The Matterhorn Mill included the four systems of a typical mill, as described in period texts, such as Antoine Marc Gaudin's Flotation (New York: McGraw Hill, 1932): 1) an ore delivery system, 2) a crushing and storage section, 3) the concentration section, and 4) filtration and bagging/shipping section. Typical of a flotation mill, the ore from the mine traveled down through fifteen levels to be reduced into concentrates. The levels augmented the economical processing of ore utilizing gravity. Nearly all the equipment remaining in the mill clearly illustrates the flotation process.
It was designed by Walter L. Reed and was built by Otto Beselack.
In 2009 it was owned by the U.S. Forest Service.
In 2020, at 100 years of age, it was announced that the mill was "undergoing a restoration project that will stabilize the remaining architecture, improve the structural integrity and cleanup the mining waste and tailings piles. Following the completion of the mill repairs and cleanup, a historic preservation easement will facilitate the conveyance of the mill from the U.S. Forest Service to San Miguel County to sustain the Matterhorn Mill for public enjoyment and education."
It is located off Colorado State Highway 145, about south of Ophir, within what was the historic townsite of Matterhorn, Colorado, which was known as San Bernardo, Colorado before 1908.
See also
Trout Lake (Colorado)
References
External links
National Register of Historic Places in San Miguel County, Colorado
Buildings and structures completed in 1920
Industrial buildings and structures on the National Register of Historic Places in Colorado
Flotation mills | Valley View Leasing and Mining Company Mill | [
"Engineering"
] | 767 | [
"Flotation mills",
"Mining equipment"
] |
70,704,819 | https://en.wikipedia.org/wiki/Maria%20Ruth%20B.%20Pineda-Cortel | Dr. Maria Ruth B. Pineda-Cortel is an associate professor and laboratory coordinator at the University of Santo Tomas (UST) where she teaches at the Department of Medical Technology of the Faculty of Pharmacy. She also does research at the university's Research Center for the Natural Sciences and Applied Sciences (RCNAS). Pineda-Cortel has done extensive research focusing on gestational diabetes mellitus (GDM, also known as diabetes during pregnancy) and polycystic ovarian syndrome (PCOS) as a way to shed light on diseases that only affect women. As a woman of science, she advocates and works towards improving healthcare for women. Pineda-Cortel has also done research covering many health-related issues that include the effects of climate change on infectious diseases that are prevalent in the Philippines, such as dengue and malaria.
Education
Pineda-Cortel studied at the University of Santo Tomas in Manila, Philippines where she received all of her degrees: Bachelor of Science in Medical Technology, Master of Science in Medical Technology, and Doctor of Philosophy with a major in Biological Sciences.
Career and research
Gestational Diabetes Mellitus
Pineda-Cortel focuses her research on early-detection and diagnosis of GDM in pregnant women in the Philippines. The prevalence of GDM in the Philippines is around 30%, and Pineda-Cortel aims to increase accessibility and availability of standard diagnostic and screening tests for GDM to prevent further health complications in the mother and the baby. Her goal is to find early genetic biomarkers that can be identified in pregnant women to prevent the development of GDM. She carries out her experiments by collecting blood samples every trimester from a group of pregnant women with no diabetes (non-GDM group) and another group of pregnant women that have diabetes before pregnancy and/or had GDM during past pregnancies (GDM group). The RNA from the blood samples are then analyzed through differential gene expression to compare the read counts of relevant genes between the non-GDM group and the GDM group during first, second, and third trimester. In one of her studies, she concludes that the gene variant rs7754840 of the CDKAL1 gene (known to inhibit insulin production) does not increase susceptibility to GDM. Another one of her studies also suggests that iron deficiency anemia in pregnant women decreases the risk of developing GDM. Pineda-Cortel's research is an effort to end the cycle of transgenerational diabetes as its prevalence continues to increase all over the world.
Dengue and climate change
Pineda-Cortel also does research to determine the effects of climate change and other environmental factors on dengue incidence and number of cases per region. Her studies show a strong correlation between the incidence of dengue and temperature, rainfall and humidity. Because the Philippines lie in the tropics, these three climate variables are the main driving force of dengue fever. Warmer temperatures speed up the extrinsic incubation period of the dengue virus and the development of mosquitoes which increases disease transmission rates. In addition, her research also demonstrates that rainfall contributes to an increase in dengue cases as stagnant water provides breeding grounds for mosquitoes. With these contributing factors in mind, Pineda-Cortel developed prediction models of dengue cases in four studied regions in the Philippines.
Selected publications
Awards and recognition
References
External links
Wikipedia Student Program
21st-century Filipino scientists
21st-century Filipino women scientists
Filipino women scientists
Diabetes
Filipino biologists
Women biologists
Climate change
Dengue fever
Filipino educators
21st-century Filipino women educators
Tropical diseases
Parasitic diseases
Clinical chemists
Living people
Year of birth missing (living people)
ASEAN
University of Santo Tomas
University of Santo Tomas alumni
Academic staff of the University of Santo Tomas | Maria Ruth B. Pineda-Cortel | [
"Chemistry"
] | 780 | [
"Biochemists",
"Clinical chemists"
] |
70,705,439 | https://en.wikipedia.org/wiki/17%20Delphini | 17 Delphini is a solitary star in the equatorial constellation Delphinus. It has an absolute magnitude of −0.64 and apparent magnitude of 5.18, allowing it to be faintly seen with the naked eye. Located 517 light years away, it is approaching the Solar System with a heliocentric radial velocity of .
17 Delphini is an orange giant that is most likely on the horizontal branch (84% probability). At present it has 2.33 times the mass of the Sun, but at an age of 832 million years — has expanded to 23.36 times the radius of the Sun. It shines at from its enlarged photosphere at an effective temperature of 4,616 K, giving it an orange glow. 17 Del has an iron abundance 64% that of the Sun and spins modestly with a projected rotational velocity of .
17 Del is suspected to be a variable star of unknown type ranging from 5.16 to 5.27.
References
Delphinus
K-type giants
Delphini, 17
199253
103294
8011
Suspected variables
BD+13 4572 | 17 Delphini | [
"Astronomy"
] | 229 | [
"Delphinus",
"Constellations"
] |
70,705,948 | https://en.wikipedia.org/wiki/Proacrodon | Proacrodon is a dubious genus of extinct mammal from South America. Its type species is Proacrodon transformatus. The only known specimen, a lower premolar or molar, is now lost, and its affinities are unknown.
In 1899, Santiago Roth named the new genus and species Proacrodon transformatus on the basis of a single tooth collected in Patagonia. The genus name comes from Greek πρό "before", άκρος "pointed", and όδών "tooth", and refers to the shape of the tooth, which rises higher in its anterior portion than its posterior portion. Roth compared the taxon to Megacrodon, which he named in the same paper, and to Hyrachyus. Florentino Ameghino synonymized Proacrodon with his own genus Trimerostephanus without seeing the specimen firsthand. In 1904, Palmer listed both Proacrodon and Trimerostephanos as members of Isotemnidae. In 1948 George Gaylord Simpson listed the taxon as a possible litoptern and concluded that the taxon was a nomen vanum, viewing Ameghino's proposal of synonymy with Trimerostephanos as possible but not reliable.
The locality where the tooth was collected is not known with certainty, but was probably in the Musters Formation.
References
Works cited
Litopterns
Nomina dubia
Fossil taxa described in 1899
Prehistoric placental genera | Proacrodon | [
"Biology"
] | 302 | [
"Biological hypotheses",
"Nomina dubia",
"Controversial taxa"
] |
70,706,897 | https://en.wikipedia.org/wiki/Naphthablin | Naphthablin is a naphthoquinone compound with the molecular formula C29H36O8 which is produced by the bacterium Streptomyces aculeolatus.
References
Heterocyclic compounds with 4 rings
Oxygen heterocycles
Isobutyrate esters
Primary alcohols
Triols
1,4-Naphthoquinones
Hydroxyketones | Naphthablin | [
"Chemistry"
] | 79 | [
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
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