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62,189,939 | https://en.wikipedia.org/wiki/Jos%20de%20Villiers | Josias Eduard de Villiers (nicknamed Jos, Koelenhof; 27 December 1843 – 16 August 1898) was a Cape Colony and South African Republic surveyor, politician, and amateur astronomer. He surveyed the first neighborhood in Johannesburg, Randjeslaagte. He predicted that Johannesburg would become a city rather than disappearing like other ghost towns (as most South African civil servants of the era did), and De Villiers Street there is named after him.
Early life
From Stellenbosch, De Villiers was the second son of Jacob Isaac de Villiers by his first wife, Ester Elisabeth Johanna Hoffman. De Villiers grew up on Koelenhof farm and later in Stellenbosch, studying at the South African College and becoming a surveyor. In 1863, he was still in Cape Colony working as a surveyor, but shortly afterward left for the Orange Free State. In 1865, he was tasked with surveying the farms in Ladybrand, part of the so-called "Conquered Area" from the Free State-Basotho Wars. He settled in Boshof and represented the area from 1875 to 1882 in the Volksraad (Parliament) of the Free State. After the resolution of the long-running diamond fields dispute of the 1870s stemming from Sir Henry Barkly declaring the entire area British territory, the Free State appointed De Villiers to define its boundary with Griqualand West.
On the rand
By the time gold was discovered in the Witwatersrand, De Villiers had settled in the area. Sir Joseph Robinson, 1st Baronet surveyed mining claims on Langlaagte Farm where gold would first be found, and he also inspected the 600 plots that made up the spoil tip Randjeslaagte, the seed of Johannesburg, with the help of W.H.A. Pritchard between 19 October and 3 November 1886. The streets ran north to south and east to west artificially, with no regard to terrain, and were quite broad, countering the Transvaal government's expectation of a mere mining hamlet similar to Barberton or Pilgrim's Rest. His goal was to offer as many housing plots as possible to save money, while selling the corners as valuable business offices.
The massive influx of prospective miners as well as the first merchants led the city to contract with De Villiers for expansion from 600 to 986 plots. To this end, in April 1887, the two parts of Randjeslaagte were thus connected. At the time, the claims were not proving lucrative, and the Ford and Jeppe syndicate paying for the surveys was under pressure from residents to reduce mining activity. De Villier's street plan continued from southern Marshalltown, but at the end of Bree Street some streets remained unjoined in the "nod," but the plan was never to connect Randjeslaagte together. His plots continued west to Ferreirasdorp, but to the east the owners of plots in Randjeslaagte began auctioning off land on 8 June 1887 that would become the city's first upscale suburb, Doornfontein.
Last years
In 1895, De Villiers sold his property in Johannesburg to move to Cape Town and devote himself full-time to his hobby of astronomy. In August 1896, he joined an expedition to the island of Vadsøya in Norway to view an eclipse, using his surveying skills to set up their equipment. Two years later, he was one of 16 killed in a train crash in Mostert's Hoek coming back home from Vryburg, where he had been campaigning for the Parliament of the Cape of Good Hope as a candidate for the Afrikaner Bond. At the time of his death, he was working on building an elaborate observatory at his house, Ambleside, in Sea Point.
Personal life
De Villiers and his wife Christina Maria Elizabeth de Vos had three sons.
Sources
(en) Potgieter, D.J. (chief ed.) 1972. Standard Encyclopaedia of Southern Africa. Cape Town: Nasionale Opvoedkundige Uitgewery.
(af) Sandler, E.A. in Beyers, C.J. (chief ed.) (1981). Suid-Afrikaanse Biografiese Woordeboek, vol. IV. Durban: Butterworth & Kie (Edms) Bpk.
(af) Van der Waal, Gerhard-Mark (1986). Van mynkamp tot metropolis. Die boukuns van Johannesburg, 1886–1940. Johannesburg: Chris van Rensburg Publikasies (Edms.) Beperk.
1898 deaths
1843 births
Cape Colony people
Orange Free State people
Astronomers
South African Republic politicians
Surveyors
Railway accident deaths in South Africa | Jos de Villiers | [
"Astronomy"
] | 971 | [
"People associated with astronomy",
"Astronomers"
] |
62,194,268 | https://en.wikipedia.org/wiki/Robert%20Kennedy%20%28chemist%29 | Robert Travis Kennedy is an American chemist specializing in bioanalytical chemistry including liquid chromatography, capillary electrophoresis, and microfluidics. He is currently the Hobart H. Willard Distinguished University Professor of Chemistry and the chair of the department of chemistry at the University of Michigan. He holds joint appointments with the Department of Pharmacology and Department Macromolecular Science and Engineering. Kennedy is an Associate Editor of Analytical Chemistry and ACS Measurement Science AU.
Early life and education
Kennedy was born on November 11, 1962, in Sault Ste. Marie, Michigan. He earned a Bachelor of Science degree in chemistry at the University of Florida in 1984 and a Ph.D. from the University of North Carolina-Chapel Hill (UNC) in 1988 while working under James Jorgenson. He was an NSF post-doctoral fellow at UNC from 1989-1991 with R. Mark Wightman.
Academic career and research interests
Kennedy became a professor of chemistry at the University of Florida in 1991. After 11 years, he moved to the University of Michigan. He has graduated approximately 80 graduate students. Kennedy’s research focuses on developing analytical instrumentation and methods that can help solve biological problems. He is considered a leader in the field of analytical chemistry, and an expert in endocrinology, neurochemistry, and high-throughput analysis. Major contributions to analytical chemistry include affinity probe capillary electrophoresis, in vivo neurochemical measurements, and ultra-high pressure liquid chromatography. He has been a Lilly Analytical Research Fellow, Alfred P. Sloan Fellow, NSF Presidential Faculty Fellow, and AAAS Fellow.
Honors and awards
EAS Award for Outstanding Achievements in the Fields of Analytical Chemistry (2023)
Martin Medal (2019)
Ralph N. Adams Award in Bioanalyical Chemistry (2016)
ACS Award in Chromatography (2017)
CASSS Award for Outstanding Achievements in Separation Science (2017)
Marcel Golay Award for Lifetime Achievement in Capillary Chromatography (2012)
Eastern Analytical Symposium Award for Separation Science (2012)
McKnight Award for Technical Innovations in Neuroscience (2010)
Rackham Distinguished Faculty Achievement Award (2009)
American Microchemical Society’s Benedetti-Pichler Memorial Award (2001)
References
American chemists
University of Michigan faculty
Electrophoresis
Chromatography
1962 births
Living people
University of Florida alumni
University of North Carolina at Chapel Hill alumni
Fellows of the American Association for the Advancement of Science
Recipients of the Presidential Early Career Award for Scientists and Engineers
People from Sault Ste. Marie, Michigan
University of Florida faculty
Chemists from Michigan | Robert Kennedy (chemist) | [
"Chemistry",
"Biology"
] | 537 | [
"Chromatography",
"Separation processes",
"Instrumental analysis",
"Biochemical separation processes",
"Molecular biology techniques",
"Electrophoresis"
] |
62,194,568 | https://en.wikipedia.org/wiki/Karletta%20Chief | Karletta Chief is a Diné hydrologist, best known for her work to address environmental pollution on the Navajo Nation and increase the participation of Native Americans in STEM. She is a professor at the University of Arizona.
Education
Chief earned her B.S. and M.S. in civil and environmental engineering at Stanford University. She completed her PhD in hydrology and water resources at the University of Arizona in 2007, where she is now a faculty member.
Career
One of Chief's research interests is addressing food, energy and water challenges in Indigenous communities with methods that include their traditional values. In particular, she has researched the impacts of the 2015 Gold King Mine spill on residents of the Navajo Nation. Her research regarding the effects of the Gold King spill have aided several communities affected by the disaster. As part of this work, Chief gives public presentations in the Navajo language, especially to farmers, ranchers, and families who are affected by pollution and mining waste. She has said that her scientific research and her identity are closely linked, telling Science Friday, “my identity is water-based [from the Bitter Water Clan]. And so that motivates me to do the work that I do.”
Chief was featured in a short film produced by Science Friday in 2018, and is one of the interviewees in the feature documentary Hacking at Leaves.
Selected awards and honors
Most Promising Engineer/Scientist, American Indian Science and Engineering Society (AISES), 2011
Distinguished Alumni Scholar, Stanford University, 2013
Native American 40 Under 40, National Center for American Indian Enterprise Development, 2015
Professional of the Year, AISES, 2016
Woman of the Year, Phoenix Indian Center, 2016
Featured Speaker, Society for the Advancement of Chicanos/Native Americans in STEM (SACNAS), 2019
Ambassador Award (2020)
Fellow, American Geophysical Union
Selected publications
Chief, K., R. E. Emanuel, and O. Conroy-Ben (2019), Indigenous symposium on water research, education, and engagement, Eos, 100, https://doi.org/10.1029/2019EO114313. Published on 24 January 2019.
References
American women scientists
Hydrologists
Native American women academics
American women academics
Native American academics
Navajo scientists
Stanford University School of Engineering alumni
Year of birth missing (living people)
Living people
21st-century Native American women
Native American women scientists
Women hydrologists
Navajo women
21st-century Native American scientists
Native American women engineers | Karletta Chief | [
"Environmental_science"
] | 493 | [
"Hydrology",
"Hydrologists"
] |
62,198,068 | https://en.wikipedia.org/wiki/Comparison%20of%20OS%20emulation%20or%20virtualization%20apps%20on%20Android | There are many apps in Android that can run or emulate other operating systems, via utilizing hardware support for platform virtualization technologies, or via terminal emulation. Some of these apps support having more than one emulation/virtual file system for different OS profiles, thus the ability to have or run multiple OS's. Some even have support to run the emulation via a localhost SSH connection (letting remote ssh terminal apps on device access the OS emulation/VM, VNC, and XSDL. If more than one of these apps that support these protocols or technologies are available on the android device, via androids ability to do background tasking the main emulator/VM app on android can be used to launch multiple emulation/vm OS, which the other apps can connect to, thus multiple emulated/VM OS's can run at the same time. However, there are a few emulator or VM apps that require that the android device to be rooted for the app to work, and there are others that do not require such. Some remote terminal access apps also have the ability to access Android's internally implemented Toybox, via device loopback support. Some VM/emulator apps have a fixed set of OS's or applications that can be supported.
Since Android 8 (Oreo) and later versions of Android, some of these apps have been reporting issues as Google has heightened the security of file-access permissions on newer versions of Android. Some apps have difficulties or have lost access to SD card. It is also been reported that some of the apps have trouble utilizing packages like udisks2, Open vSwitch, Snort (software), and Mininet, due to new hardware or Android API restrictions on apps that have been put into place in the recent years. Due to this, many of these app developers and their community members are stating that the emulation/VM app can run itself and an OS without being rooted, however not all packages will be able to run unless the device is rooted.
OS emulators or VM Android apps
The following is a list of OS emulators and OS virtualization Android apps.
Terminal emulation apps utilizing internal OS
See also
Comparison of platform virtualization software
List of computer system emulators
OS virtualization and emulation on Android
Mobile virtualization
References
Software comparisons
Android (operating system) | Comparison of OS emulation or virtualization apps on Android | [
"Technology"
] | 491 | [
"Software comparisons",
"Computing comparisons"
] |
62,198,576 | https://en.wikipedia.org/wiki/Karen%20Aplin | Karen Aplin is a British atmospheric and space physicist. She is currently a professor at the University of Bristol. Aplin has made significant contributions to interdisciplinary aspects of space and terrestrial science, in particular the importance of electrical effects on planetary atmospheres. She was awarded the 2021 James Dungey Lectureship of the Royal Astronomical Society.
Education and research career
After attending The High School, Gloucester, Aplin completed a BSc in Natural Sciences at Durham University in 1997. She was president of Durham University Orchestral Society and received the Norah C. Bowes bequest for the arts. She completed her PhD in experimental atmospheric physics in the Department of Meteorology at the University of Reading in 2000. She took up research posts at the University of Hertfordshire and the STFC Rutherford Appleton Laboratory, working on aspects of space and atmospheric instrumentation, before becoming head of the physics laboratories at Oxford University in 2009. In 2018 she moved to the University of Bristol.
Work on atmospheric electricity
Aplin's research has focussed on innovative instrumentation as applied to problems in space and atmospheric science, in particular electrical effects and measurements. She currently maintains the Snowdon space-weather observatory. She has performed experimental work on the atmospheric effects of ions formed by cosmic rays, but has been keen to stress that the formed "particles are too small to act as cloud condensation nuclei", and thus there is unlikely to be a strong cosmic-ray link to global cloud cover.
Her work on atmospheric electricity also extends to the link between volcanoes, lightning and radon gas, and to other solar system bodies, in particular the ultraviolet and galactic cosmic ray effects on Neptune's atmosphere.
In a similarly interdisciplinary spirit, Aplin has researched the influence of the climate and weather on western orchestral composers.
Awards and recognition
2021: James Dungey Lectureship of the Royal Astronomical Society.
2019: Visiting professor at the University of Bath (previously visiting senior research fellow)
2015 – present: Editor of the Journal of Electrostatics
2009 – present: Editor for the open-access journal History of Geo- and Space Sciences
References
Living people
British space scientists
Atmospheric electricity
Academics of the University of Bristol
Alumni of the University of Reading
Year of birth missing (living people)
British women physicists
Alumni of Trevelyan College, Durham | Karen Aplin | [
"Physics"
] | 454 | [
"Physical phenomena",
"Electrical phenomena",
"Atmospheric electricity"
] |
51,756,257 | https://en.wikipedia.org/wiki/Big%20memory | Big memory computers are machines with a large amount of random-access memory (RAM). The computers are required for databases, graph analytics, or more generally, high-performance computing, data science and big data. Some database systems called in-memory databases are designed to run mostly in memory, rarely if ever retrieving data from disk or flash memory. See list of in-memory databases.
Details
The performance of big memory systems depends on how the central processing units (CPUs) access the memory, via a conventional memory controller or via non-uniform memory access (NUMA). Performance also depends on the size and design of the CPU cache.
Performance also depends on operating system (OS) design. The huge pages feature in Linux and other OSes can improve the efficiency of virtual memory. The transparent huge pages feature in Linux can offer better performance for some big-memory workloads. The "Large-Page Support" in Microsoft Windows enables server applications to establish large-page memory regions which are typically three orders of magnitude larger than the native page size.
References
Big data
Data management
Distributed computing problems
Technology forecasting
Transaction processing | Big memory | [
"Mathematics",
"Technology"
] | 230 | [
"Distributed computing problems",
"Computational problems",
"Data management",
"Data",
"Big data",
"Mathematical problems"
] |
51,757,408 | https://en.wikipedia.org/wiki/NGC%20256 | NGC 256 (also known as ESO 29-SC11) is open cluster in the Tucana constellation. It was discovered by John Frederick William Herschel on April 11, 1834.
References
External links
ESO objects
0256
Open clusters
Tucana | NGC 256 | [
"Astronomy"
] | 51 | [
"Tucana",
"Constellations"
] |
51,757,457 | https://en.wikipedia.org/wiki/NGC%20257 | NGC 257 is a spiral galaxy in the Pisces constellation. It was discovered on December 29, 1790, by Frederick William Herschel.
References
Notes
External links
Astronomical objects discovered in 1790
Pisces (constellation)
Spiral galaxies
002818
00493
0257 | NGC 257 | [
"Astronomy"
] | 55 | [
"Pisces (constellation)",
"Constellations"
] |
51,757,526 | https://en.wikipedia.org/wiki/NGC%20258 | NGC 258 is a lenticular galaxy located in the Andromeda constellation. It was discovered by George Stoner in 1848.
References
External links
Andromeda (constellation)
Lenticular galaxies
Astronomical objects discovered in 1848
0258
002829 | NGC 258 | [
"Astronomy"
] | 49 | [
"Andromeda (constellation)",
"Constellations"
] |
51,757,886 | https://en.wikipedia.org/wiki/NGC%20259 | NGC 259 is a spiral galaxy located in the constellation Cetus. It was discovered by William Herschel in 1786.
One supernova has been observed in NGC 259: SN 2017jbj (type II, mag. 16.9).
References
External links
Cetus
Spiral galaxies
Astronomical objects discovered in 1786
0259
002820 | NGC 259 | [
"Astronomy"
] | 69 | [
"Cetus",
"Constellations"
] |
51,758,341 | https://en.wikipedia.org/wiki/Susan%20Brantley | Susan L. Brantley (born 1958) is an American geologist and geochemist who is the Dr. Hubert Barnes and Dr. Mary Barnes Professor at Pennsylvania State University. Her research dominantly studies interactions between fluids and minerals at low temperatures, biological reactions in water-rich fluids within soils, and the geochemical processes that convert rock into soil. However, among many other topics, she has also published work on carbon dioxide emissions from volcanoes, and the environmental impact of shale gas extraction and nuclear waste disposal. During her career, Brantley has published over 200 research papers and book chapters, has been awarded academic prizes and fellowships by many of the world's leading geoscience societies, and has been described as "one of the leading aqueous geochemists of her generation."
Awards and recognition
Fellowships and memberships
Fellow of the American Geophysical Union
Fellow of the Geological Society of America
Fellow of the Geochemical Society
Fellow of the European Association of Geochemistry
Fellow of the International Association of GeoChemistry
Member of the National Academy of Sciences
Professional awards
Robert Garrels Award, The Geobiology Society (2019)
Urey Medal of the European Association of Geochemistry (2018)
Geochemistry Division Medal of the American Chemical Society (2017)
Wollaston Medal of the Geological Society of London (2016)
Honorary doctorate, University of Lausanne, Switzerland (2013)
Presidential Award of the Soil Science Society of America (2012)
Honorary doctorate, University of Toulouse III - Paul Sabatier University, France (2011)
Arthur L. Day Medal of the Geological Society of America (2011)
References
Living people
Date of birth missing (living people)
American geochemists
American women geologists
Pennsylvania State University faculty
Princeton University alumni
Fellows of the American Geophysical Union
Members of the United States National Academy of Sciences
Wollaston Medal winners
21st-century American geologists
21st-century American chemists
21st-century American women scientists
1958 births
American women academics
Presidents of the Geochemical Society | Susan Brantley | [
"Chemistry"
] | 398 | [
"Geochemists",
"Presidents of the Geochemical Society",
"American geochemists"
] |
51,758,505 | https://en.wikipedia.org/wiki/Q-system%20%28genetics%29 | Q-system is a genetic tool that allows to express transgenes in a living organism. Originally the Q-system was developed for use in the vinegar fly Drosophila melanogaster, and was rapidly adapted for use in cultured mammalian cells, zebrafish, worms and mosquitoes. The Q-system utilizes genes from the qa cluster of the bread fungus Neurospora crassa, and consists of four components: the transcriptional activator (QF/QF2/QF2w), the enhancer QUAS, the repressor QS, and the chemical de-repressor quinic acid. Similarly to GAL4/UAS and LexA/LexAop, the Q-system is a binary expression system that allows to express reporters or effectors (e.g. fluorescent proteins, ion channels, toxins and other genes) in a defined subpopulation of cells with the purpose of visualising these cells or altering their function. In addition, GAL4/UAS, LexA/LexAop and the Q-system function independently of each other and can be used simultaneously to achieve a desired pattern of reporter expression, or to express several reporters in different subsets of cells.
Origin
The Q-system is based on two out of the seven genes of the qa gene cluster of the bread fungus Neurospora crassa. The genes of the qa cluster are responsible for the catabolism of quinic acid, which is used by the fungus as a carbon source in conditions of low glucose. The cluster contains a transcriptional activator qa-1F, a transcriptional repressor qa-1S, and five structural genes. The qa-1F binds to a specific DNA sequence, found upstream of the qa genes. The presence of quinic acid disrupts interaction between qa-1F and qa-1S, thus disinhibiting the transcriptional activity of qa-1F.
Genes qa-1F, qa-1S and the DNA binding sequence of qa-1F form the basis of the Q-system. The genes were renamed to simplify their use as follows: transcriptional activator qa-1F as QF, repressor qa-1S as QS, and the DNA binding sequence as QUAS. The quinic acid represents the fourth component of the Q-system.
The original transactivator QF appeared to be toxic when expressed broadly in Drosophila. To overcome this problem, two new transactivators were developed: QF2 and QF2w.
Use in Drosophila
Basic use
The Q-system functions similarly to, and independently of, the GAL4/UAS and the LexA/LexAop systems. QF, QF2 and QF2w are analogous to GAL4 and LexA, and their expression is usually under the control of cell-type specific promoter, such as nsyb (to target neurons) or tubulin (to target all cells). QUAS is analogous to UAS and LexAop, and is placed upstream of an effector gene, such as GFP. QS is analogous to GAL80, and may be driven by any promoter (e.g. tubulin-QS). Quinic acid is a unique feature of the Q-system, and it must be fed to the flies or maggots in order to alleviate the QS-induced repression. In some ways, quinic acid is analogous to temperature in the case of GAL80ts.
In its basic form, two transgenic fly lines, one containing a QF transgene and the other one containing a QUAS transgene, are crossed together. Their progeny that had both a QF transgene and a QUAS transgene will be expressing a reporter gene in a subset of cells (e.g. nsyb-QF2, QUAS-GFP flies express GFP in all neurons). If a fly also expresses QS in some of the cells, the activity of QF will be repressed in these cells, but it may be restored of a fly is fed quinic acid (e.g. a nsyb-QF2, QUAS-GFP, tub-QS fly expresses no GFP when its diet doesn't contain quinic acid, and expresses GFP in its neurons when fed quinic acid). The use of QS repressor and quinic acid allows to fine-tune the temporal control of transgene expression.
Chimeric transactivators
Chimeric transactivators GAL4QF and LexAQF allow to combine the use of all three binary expression systems. GAL4QF binds to UAS, and may be repressed by QS while being unaffected by GAL80. Similarly, LexAQF binds to LexAop, and may be repressed by QS. LexAQF represents a useful extension of the LexA/LexAop system that doesn't have its own repressor.
Intersectional expression
A variety of expression patterns may be achieved by combination of the three binary expression systems and the FLP/FRT or other recombinases. Expression patterns may be constructed as AND, OR, NOR etc. logic gates to e.g. narrow down expression patterns of available GAL4 lines. The resulting expression pattern somewhat depends on the developmental timing of activation of the transcription factors (discussed in ).
Use in other organisms
Q-system appeared to be working successfully in a variety of organisms. It has been used to drive expression of luciferase, as a proof of principle, in cultured mammalian cells. In zebrafish the Q-system has been successfully used with several tissue-specific promoters, and was shown to work independently of the GAL4/UAS system when expressed in the same cell. In C. elegans the Q-system has been shown to work in muscles and in neuronal tissue. In 2016, the Q-system was used to target, for the first time, the olfactory neurons of malaria mosquitoes Anopheles gambiae. In 2019, the Q-system in Anopheles mosquitoes was used to examine the functional responses of olfactory neurons to odors. In 2019, the Q-system was introduced into the Aedes aegypti mosquito to capture tissue specific expression patterns. These successes make the Q-system the system of choice when developing genetic tools for other organisms. Currently the main shortcoming of the Q-system is the low number of available transgenic lines, but it will be overcome as the scientific community creates and shares these resources, such as by the use of the GAL4>QF2 HACK system to convert existing GAL4 transgenic insertions to QF2. DNA binding domain of QF2 fused with VP16 transcriptional activator domain was successfully applied in Penicillium to gain control over the penicillin producing secondary metabolite gene cluster in a scalable manner.
References
Genetics | Q-system (genetics) | [
"Biology"
] | 1,471 | [
"Genetics"
] |
51,758,582 | https://en.wikipedia.org/wiki/Cell%20division%20orientation | Cell division orientation is the direction along which the new daughter cells are formed. Cell division orientation is important for morphogenesis, cell fate and tissue homeostasis. Abnormalities in the cell division orientation leads to the malformations during development and cancerous tissues. Factors that influence cell division orientation are cell shape, anisotropic localization of specific proteins and mechanical tensions.
Implication for morphogenesis
Cell division orientation is one of the mechanisms that shapes tissue during development and morphogenesis. Along with cell shape changes, cell rearrangements, apoptosis and growth, oriented cell division modifies the geometry and topology of live tissue in order to create new organs and shape the organisms. Reproducible patterns of oriented cell divisions were described during morphogenesis of Drosophila embryos, Arabidopsis thaliana embryos, Drosophila pupa, zebrafish embryos and mouse early embryos. Oriented cell divisions contribute to the tissue elongation and the release of mechanical stress. While in the first case oriented cell division acts as active contributor to the morphogenesis, the latter case is a passive response to the external mechanical tensions.
Implication for tissue homeostasis
In several tissues, such as columnar epithelium, the cells divide along the plane of the epithelium. Such divisions insert new formed cells in the epithelium layer. The disregulation of the orientation of cell divisions result in the creation of the cell out of epithelium and is observed at the initial stages of cancer.
Regulation
More than a century ago Oskar Hertwig proposed that the cell division orientation is determined by the shape of the cell (1884), known as Hertwig rule. In the epithelium the cells 'reads' its shape through the specific cell junction called tricellular junctions (TCJ). TCJ provide mechanical and geometrical clues for the spindle apparatus to ensure that cell divide along its long axis. Several factors could regulate cell shape and therefore orientation of cell division. Among these factors is the anisotropic mechanical stress. This stress could be the result of the external mechanical deformation of generated intracellularly by non-isotropic localization of specific proteins.
References
Cell biology
Cell anatomy
Cell cycle
Cellular processes
Developmental biology
Morphology (biology) | Cell division orientation | [
"Biology"
] | 473 | [
"Behavior",
"Developmental biology",
"Cell biology",
"Morphology (biology)",
"Reproduction",
"Cellular processes",
"Cell cycle"
] |
51,758,742 | https://en.wikipedia.org/wiki/HD%20150248 | HD 150248 is a Sun-like star 87 light-years (26.6 parsecs) from the Sun. HD 150248 is a G-type star and a near solar twin. HD 150248's photometric color is also very close to that of the Sun; however, it has a lower abundance of metals, and has an apparent visual magnitude of 7.02. At 6.2 billion years old, this star is 1.6 billion years older than the Sun and has passed the stable burning stage. HD 150248 is found on the border between the constellations Scorpius and Ara.
To date, no solar twin with an exact match to that of the Sun has been found. However, there are some stars that come very close to being identical, and thus considered solar twins by the astronomical community. An exact solar twin would be a G2V star with a 5,778K temperature, be 4.6 billion years old, with solar metallicity, and a 0.1% solar luminosity variation. Stars with an age of 4.6 billion years, such as the Sun, are at the most stable state. Proper metallicity and size are also very important to low luminosity variation.
Comparison to the Sun
See also
List of nearest stars
References
150248
G-type main-sequence stars
Solar analogs
081746
Durchmusterung objects
Scorpius | HD 150248 | [
"Astronomy"
] | 296 | [
"Scorpius",
"Constellations"
] |
51,758,810 | https://en.wikipedia.org/wiki/VISTA%20%28protein%29 | V-domain Ig suppressor of T cell activation (VISTA) is a type I transmembrane protein that functions as an immune checkpoint and is encoded by the VSIR gene.
Structure and function
VISTA is approximately 50 kDa and belongs to the immunoglobulin superfamily and has one IgV domain.
VISTA is part of the B7 family, is primarily expressed in white blood cells and its transcription is partially controlled by p53. There is evidence that VISTA can act as both a ligand and a receptor on T cells to inhibit T cell effector function and maintain peripheral tolerance. Similarly, VISTA and TIM-3 may co-exist on macrophages infiltrating different human and mouse tumours where they can co-regulate immunotherapy resistance.
Clinical significance
VISTA is produced at high levels in tumor-infiltrating lymphocytes, such as myeloid-derived suppressor cells and regulatory T cells, and its blockade with an antibody results in delayed tumor growth in mouse models of melanoma and squamous cell carcinoma. It is also up-regulated in tumour-associated macrophages in various malignancies, including melanoma, especially in immunotherapy-resistant human context.<ref name =
Monocytes from HIV-infected patients produce higher levels of VISTA compared to uninfected individuals. The increased VISTA levels correlated with an increase in immune activation and a decrease in CD4-positive T cells.
As a drug target
There is an ongoing cancer immunotherapy clinical trial for a monoclonal antibody targeting VISTA in advanced cancer. Preliminary results of the phase I clinical trial show good safety tolerance and anti-cancer activity in patients with advanced tumours. Another ongoing clinical trial involves a small molecule that antagonizes the programmed death-ligands 1 and 2 (PD-L1 and PD-L2), and VISTA pathways in patients with advanced solid tumors or lymphomas.
References
Further reading
External links
Immune system | VISTA (protein) | [
"Biology"
] | 417 | [
"Immune system",
"Organ systems"
] |
51,759,087 | https://en.wikipedia.org/wiki/HD%20117939 | HD 117939 is a Sun-like star in the southern constellation of Centaurus. With an apparent visual magnitude of 7.29 it is too faint to be viewed with the naked eye, but is within the range of binoculars or a small telescope. It is located at a distance of 98.5 light years from the Sun based on parallax measurements, and is drifting further away with a radial velocity of +82 km/s. This is an intermediate disk star with a high proper motion, traversing the celestial sphere at an angular rate of .
An ordinary G-type main-sequence star with a stellar classification of G4V, this star is an "excellent photometric match for the Sun"; the atmospheric properties of the star make it a near solar twin. It is older than the sun at 6.1 billion years, but is more chromospherically active.
To date no exact solar twin (precisely matching all important properties of the Sun) has been found. However, there are some stars that come very close to being identical to the Sun, and as such are dubbed solar twins by astronomers. An exact solar twin would be a 4.6 billion years old G2V star with a 5,778K temperature, the correct metallicity, and a 0.1% solar luminosity variation. G2V stars with an age of 4.6 billion years or more have typically reached their most stable state. Proper metallicity and size are also important to low luminosity variation.
Sun comparison
Chart compares the sun to HD 117939.
See also
List of nearest stars
References
G-type main-sequence stars
Solar analogs
Centaurus
Durchmusterung objects
9450
117939
066238 | HD 117939 | [
"Astronomy"
] | 356 | [
"Centaurus",
"Constellations"
] |
51,759,243 | https://en.wikipedia.org/wiki/HD%2071334 | HD 71334 is a Sun-like star 126.7 light years (38.85 parsecs) from the Sun. HD 150248 is a G-type star and an older solar analog. It is older than the sun at 8.1 billion years, compared to the sun at 4.6 billion years old. At 8.1 billion years old, HD 71334 has passed its stable burning stage. HD 71334 has a lower metallicity that the Sun. HD 71334 is found in the constellations of Puppis. Puppis is one of the 88 modern constellations recognized by the International Astronomical Union. HD 71334 has a brightness of 7.8.
Sun comparison
Chart compares the sun to HD 71334.
See also
List of nearest stars
References
71334
G-type main-sequence stars
Solar analogs
Puppis
9263
Durchmusterung objects
041317 | HD 71334 | [
"Astronomy"
] | 191 | [
"Puppis",
"Constellations"
] |
51,759,510 | https://en.wikipedia.org/wiki/AppLovin | AppLovin Corporation is an American mobile technology company headquartered in Palo Alto, California. Founded in 2012, it operated in stealth mode until 2014. AppLovin enables developers of all sizes to market, monetize, analyze and publish their apps through its mobile advertising, marketing, and analytics platforms MAX, AppDiscovery, and SparkLabs. AppLovin operates Lion Studios, which works with game developers to promote and publish their mobile games. AppLovin also has large investments in various mobile game publishers. In 2020, 49% of AppLovin's revenue came from businesses using its software and 51% from consumers making in-app purchases.
History
AppLovin was founded in 2012 by Adam Foroughi, John Krystynak, and Andrew Karam. Foroughi stated that the AppLovin name came from Bloglovin', a content organizing company, contrary to reports of a homage to the Christopher Mintz-Plasse character from the 2007 film Superbad.
The company operated in stealth mode until 2014, raising $4 million in financing from angel investors, Streamlined Ventures and the Webb Investment Network. Before emerging from stealth mode, AppLovin acquired customers including Opentable and Spotify. In October 2014, AppLovin purchased the German mobile ad-network Moboqo.
On September 26, 2016, it was reported that AppLovin had agreed to be acquired by the Chinese private equity firm, Orient Hontai Capital, for $1.42 billion; the acquisition deal was subsequently abandoned for debt investment after opposition to the plans from CFIUS. The company was ranked #10 on the 2016 Deloitte Fast 500 North America list, and again in 2018. Foroughi was recognized on the 2017 San Francisco Business Times "40 Under 40" list.
In July 2018, AppLovin launched Lion Studios, which works with mobile developers to publish and promote their games. The convertible note facility that AppLovin received from Hontai Capital was fully refinanced in August 2018, after AppLovin raised a significant credit facility from U.S.-based investors. Hontai retains a small equity stake in AppLovin. That same month, the private equity firm KKR & Co. Inc. acquired a minority stake in AppLovin for $400 million. In September 2018, AppLovin acquired the in-app bidding company MAX. It added partnerships with Adjust and Facebook Audience Network to its in-app bidding for developers.
In 2019, the company acquired SafeDK, a software development kit management platform for ad quality, performance and stability in mobile apps. AppLovin also announced it had invested in several mobile game studios including PeopleFun, Firecraft Studios and Belka Games.
In 2020, Pocket Gamer ranked AppLovin on its list of Top 50 Mobile Game Makers. In February 2020, AppLovin invested in the mobile game studios Geewa, and Redemption Games, and it acquired Machine Zone (MZ).
In February 2021, AppLovin announced the acquisition of mobile app measurement company Adjust.
In March 2021, AppLovin company filed for an IPO in order to raise $100 million.
On April 15, 2021, AppLovin became a public company, trading on the Nasdaq under the ticker APP. AppLovin began trading at US$70 per share, with a total valuation of approximately US$24 billion.
On October 6, 2021, AppLovin announced the acquisition of mobile monetization company MoPub from Twitter for $1.1 billion. The sale was finalized on January 3, 2022.
On August 9, 2022, AppLovin made an offer to buy Unity Technologies in exchange for $17.54 billion of stock. The proposal for merger would result in Unity CEO John Riccitiello becoming the CEO of the combined entity. AppLovin's bid would require Unity to terminate its recent deal to merge with ironSource. Later that month, Unity's board rejected the offer and committed to complete its acquisition of ironSource.
References
External links
Companies based in Palo Alto, California
Marketing companies established in 2012
American companies established in 2012
2021 initial public offerings
Mobile technology companies
Companies listed on the Nasdaq
Kohlberg Kravis Roberts companies | AppLovin | [
"Technology"
] | 870 | [
"Mobile technology companies"
] |
51,766,099 | https://en.wikipedia.org/wiki/Steve%20Granick | Steve Granick is an American scientist and educator. In 2023 he joined the University of Massachusetts-Amherst as the Robert Barrett Endowed Chair of Polymer Science and Engineering, with joint appointment in the Chemistry, Physics, and Chemical Engineering Departments after serving as director of the Institute for Basic Science Center for Soft and Living Matter, an interdisciplinary blue-sky research center in Ulsan, South Korea that pursues basic science research. Until 2015 he was professor at the University of Illinois at Urbana-Champaign. He is a member of the American Academy of Arts and Sciences and the U.S. National Academy of Sciences.
Education
Granick obtained his B.A. in sociology from Princeton University in 1978 by correspondence and after initially dropping out during his Junior year. He earned his Ph.D. in chemistry from the University of Wisconsin in 1982 with John D. Ferry. He did postdoctoral work at the University of Minnesota with M. V. Tirrell and at the Collège de France with Nobel-laureate Pierre-Gilles de Gennes.
Academic career
Granick joined the faculty of the University of Illinois at Urbana-Champaign in 1985 and rose through the ranks to become Racheff Chair Professor of Materials Science and Engineering and concurrently professor of physics and biophysics, professor of chemistry, and professor of chemical and biomolecular engineering. In 2014, after thirty years at the University of Illinois, he moved to South Korea to join the Institute for Basic Science (IBS), founding the Center for Soft and Living Matter with additional appointments as professor of chemistry and physics at UNIST. In 2023 he joined the University of Massachusetts-Amherst as the Robert Barrett Endowed Chair of Polymer Science and Engineering, with joint appointment in the chemistry, physics, and chemical engineering departments.
Research and achievements
Granick is the author of more than 300 scientific articles and has made fundamental contributions to the chemistry and physics of soft materials. By early 2023, his publications had received over 30,000 citations with h-index of 93.
His research interests range from the study of active matter to the chemistry and physics of visualized macromolecules, vesicles, and supracolloidal materials. The early work in Granick's career focused on confined liquids. Granick was a pioneer in the field of nanorheology and molecular tribology. Other early work concerned molecular mobility at polymer surfaces. This progressed to later studies showing how biological membranes interact with their environments.
More recently, Granick and his research team work across disciplines to explore imaging, assembly, behavior and interactions of molecules, colloidal particles, and their assemblies. He made the first measurements of polymer surface diffusion in the key limit of dilute concentration and he identified the important class of physical problems where diffusion is anomalous yet Brownian. His laboratory became interested in many instances of molecular mobility measured at the single-molecule level, including active matter and transport in living cells.
The other principal current area of Granick's research concerns Janus colloidal particles, their self-assembly at rest and driven outside equilibrium. The scientific importance is to understand natural selection in the colloid world.
Public service and international experience
Steve Granick served as Chair of the Department of Energy (DOE) Council on Materials Panel on Polymers at Interfaces and Chair of the Division of Polymer Physics of the American Physical Society (APS). He holds or has held honorary or visiting positions at numerous international universities.
Honors and awards
Granick was elected Member of the U.S. National Academy of Sciences in 2015, and Member of the American Academy of Arts and Sciences in 2016. He is a Fellow of the American Physical Society. He is the recipient of numerous international awards, including the APS (American Physical Society) national Prize for Polymer Physics, the ACS (American Chemical Society) national Prize for Surface and Colloid Science, and the Paris-Sciences Medal.
References
External links
Steve Granick’s group at the University of Illinois
IBS Center for Soft and Living Matter in South Korea
Living people
1953 births
21st-century American physicists
20th-century American physicists
21st-century American chemists
Princeton University alumni
University of Wisconsin–Madison College of Letters and Science alumni
University of Illinois Urbana-Champaign faculty
Members of the United States National Academy of Sciences
American expatriates in South Korea
Institute for Basic Science
Tribologists
Fellows of the American Physical Society
University of Massachusetts Amherst faculty | Steve Granick | [
"Materials_science"
] | 889 | [
"Tribology",
"Tribologists"
] |
51,766,182 | https://en.wikipedia.org/wiki/Lenovo%20Z2%20Plus | The Lenovo Z2 Plus is a smartphone manufactured by Lenovo. It is a part of Lenovo's premium smartphone line in 2017, and has two variants.
Lenovo Z2 Plus is the Indian version of Lenovo Zuk Z2, that was launched in China in May, 2016.
Lenovo Z2 Plus is a mid-range smartphone launched in January 2017. It comes with a 5-inch Full HD having a resolution of 1080 x 1920 pixels with a pixel density of 441 ppi. The phone runs on a 2.15 GHz Quad core Qualcomm Snapdragon 820 processor and it comes with 4 GB RAM. 4 GB of RAM ensures the phone runs smoothly with multiple applications open simultaneously. The Lenovo Z2 Plus also packs in a graphics processor, and 64 GB of internal storage and does not support expandable storage.
The Lenovo Z2 Plus originally ran on Android 6.0.1 "Marshmallow" and is powered by a 3500 mAh battery. It is a dual SIM smartphone, and connectivity options include GPS, HotSpot, WiFi, and Bluetooth. The rear camera on the Lenovo Z2 Plus is a 13 MP with Auto Focus, Face Detection, HDR, Panorama Mode, Geo-tagging, Touch Focus, Digital Zoom, and Video Recording. The smartphone also has a Front Facing Camera capable of shooting 8 MP.
Specifications and configurations
This 5-inch device comes with an IPS display with Full HD resolution having a pixel density of 441 ppi. The body is made of Rollercage design with a fibreglass frame. It is available in two distinctive colors: Black and White. It features Adreno 530 GPU for handling high graphic demanding operations like Gaming, Virtual Reality, Augmented Reality. It comes with a maximum clockspeed of 2.15 GHz and features a Qualcomm Snapdragon 820, 64-Bit Custom Kryo Cores, Adreno 530 processor. Lenovo Z2 Plus comes in two configurations 3 GB DDR4 RAM / 32 GB ROM and 4 GB DDR4 RAM / 64 GB ROM. It weighs about 149grams and has a dimensions of 141.65mm x 68.88mm x 8.45mm.
The phone has an internal memory of 32 GB for a 3 GB RAM model and 64 GB for a 4 GB RAM model and cannot be expanded further. Lenovo Z2 Plus comes with a 3500mAh High Density Lithium polymer non-removable battery and supports fast charge. Z2 plus offers a large connectivity options like 4G, GPS with Glonass, WiFi, Hotspot, Bluetooth 4. 1, Dual SIM and USB Type C connectivity. Sensors like 3-axis gyro sensor, 3-axis electronic compass sensor, 3-axis Acceleration Sensor, Light Sensor, Hall Sensor (Proximity Sensor), Distance Sensor (Pedometer), Fingerprint recognition. The fingerprint uses a special technology called self learning fingerprint. It detects irregularities in the finger like skin peel, wound, dry skin, etc. and adjusts itself to identify the owner's fingerprint. For this purpose, it uses an advanced CAC Algorithm.
Comparison
External links
For detailed information about the phone visit this link
References
Z2 Plus
Mobile phones with 4K video recording
Mobile phones introduced in 2017
Discontinued flagship smartphones | Lenovo Z2 Plus | [
"Technology"
] | 687 | [
"Discontinued flagship smartphones",
"Flagship smartphones"
] |
51,766,238 | https://en.wikipedia.org/wiki/List%20of%20estrogens | This is a list of steroidal estrogens or derivatives of estradiol, estrone, and estriol. Most esters of these estrogens are not included in this list; for esters, see here instead.
Estradiol derivatives
17α-Substituted estradiol derivatives
Nitrogen mustard-coupled alkylating antineoplastic estradiol derivatives
17β-Aminoestrogens
Estrone derivatives
Nitrogen mustard-coupled alkylating antineoplastic estrone derivatives
Estriol derivatives
17α-Substituted estriol derivatives
Other estrogen derivatives
Epimers
Equine estrogens
See also
List of steroids
Notes
? = Chemical names that are unverified.
References
Estrogens
Steroids
Estrogens | List of estrogens | [
"Chemistry"
] | 153 | [
"nan"
] |
51,767,855 | https://en.wikipedia.org/wiki/Amanita%20flavorubens | Amanita flavorubens, also known as the yellow American blusher or the yellow American blushing amanita, is a species of fungus in the family Amanitaceae.
Description
The cap of is wide, yellow to brassy yellow to lemon yellow, sometimes dark orange brown, sometimes with pigment entirely washed out by rain becoming pallid, sometimes very deep wine red in its entirety due to bruising during development, subovoid to hemispheric to plano-convex to convex, depressed in the center, slightly tacky to dull to subviscid to subvelvety, with an incurved or downcurved, rimose, and nonstriate margin (may become slightly striate with age). It is adorned with conspicuous, woolly to felty, yellow warts; bald underneath the warts; the margin not lined, or only faintly lined at maturity.
The volva is present as yellow to orange to bright orange-yellow flocculent to confluent warts, friable, sparsely and irregularly distributed, easily removable, pulverulent, splotchy brown around the center, yellow at the edge. The flesh is thick over the stem, thinning evenly to the margin, white or yellowish, bright yellow just under the cap skin. The gills are free to very narrowly adnate, subcrowded to crowded, creamy ivory to cream to off-white, 3–8 mm broad, with a white pulverulent edge and also a small decurrent tooth. The short gills are truncate to subtruncate to subattenuate to attenuate to attenuate in steps, unevenly distributed, of diverse lengths, and plentiful. The stem is 5.2–15 cm × 0.7–1.4 cm, usually narrowing upward, infrequently narrowing downward, flaring at the top, yellow to white or very pale yellowish white and pruinose to finely powdery above the ring, white to yellow or occasionally with scattered yellowish surface fibrils and fibrillose below the ring, sometimes silky longitudinally striate.
The bulb is 15–25 × 15–21 mm, more or less turnip-shaped, with light red-pinkish stains; interior of the bulb is often the place where wine-red staining first appears intensely. The ring is membranous, superior, skirt-like, flaring then collapsing, pale yellowish white to cream to white, slightly more yellow underneath, with a thickened edge. The volva is absent or present as rings of yellow-brown warts on the bulb or brilliant yellow loose patches appressed to the stem and are large, friable, detersile, sometimes lost during collecting. The flesh is white or slightly pink, hollow or partially hollowed in the middle to stuffed.
The spores measure 7.8–11 × 5.4–7 μm and are ellipsoid to elongate (infrequently broadly ellipsoid) and amyloid. Clamps are not present at bases of basidia.
Rain will quickly wash pigment away from the yellow-orange pileus. Bruising is sometimes reported only from the stem base for this species, but it commonly bruises throughout the fruiting body. Occasionally, especially in areas with dense root mats, specimens will be found in which the entire pileus is wine-colored from bruising during expansion through the root mat. A researcher has found one specimen with the cap intensely bruised before expansion.
The cap had a dark red brown color in the center and elsewhere ranged from brown to pale yellow brown at the cap margin. The cap warts were in concentric rings and somewhat concolorous with the surrounding cap skin, but always with a distinct yellow tint. The odor is of clean laundry.
Distribution and habitat
A. flavorubens was originally described from the U.S. state of Ohio, and is also known from forests associated with beech (Fagus grandifolia), oak (Quercus), pine (Pinus), birch (Betula), and Canadian hemlock (Tsuga canadensis) from south-eastern Canada to the state of Alabama in eastern North America, central Mexico, and south-eastern Arizona.
A. flavorubens is one of the few taxa in North America that are known to have a western population disjunct from an eastern primary area of distribution.
References
flavorubens
Fungus species | Amanita flavorubens | [
"Biology"
] | 922 | [
"Fungi",
"Fungus species"
] |
51,770,370 | https://en.wikipedia.org/wiki/Lira%20512 | Lira 512 (also known as Lira XT) was an IBM PC XT compatible computer made by the Yugoslav (now Serbian) company EI Niš in the late 1980s.
It was first presented to the public in April 1988 at the “Kompjuter ‘88” computer show in Belgrade. Soon after that, Lira 512 was also presented in Yugoslav computer press. The main purpose of Lira 512 was to be used in computer classrooms.
What separates Lira 512 from most of the other XT compatibles is that keyboard is included just above in the same case (together with the 3.5’’ floppy drive), which made it similar in appearance to the original Atari ST or the Amiga 500.
Specifications
Lira 512 has the following technical specifications:
CPU: Intel 8088 running at 4.77 MHz or 10 MHz (turbo)
ROM: 8 KB Award BIOS, expandable to 32KB
RAM: 512 KB (expandable up to 640 KB)
Operating system: MS DOS 3.21
Secondary storage: 3.5’’ Panasonic 720KB floppy drive
Display: two display adapters (only one can be used at a time)
Hercules compatible adapter (monochrome text or graphic )
CGA compatible adapter (color text , or graphic , )
Sound: beeper
I/O ports: composite, RF and DE9 RGB video output, RS-232 (DB25 male + DE9 male connector reserved for the mouse), parallel port (DB25 female connector), external floppy connector, DA15 PC joystick female connector, light pen and expansion connector
Power supply 40W
Lira has two display adapters (monochrome Hercules compatible and color CGA compatible), where the active video adapter is chosen by the back-panel switch. A 40W power adapter is also installed in the same case.
Image gallery
Other Lira models
Lira XT Tower
Lira XT Tower was released about a year after the original Lira 512, because it was realized that the compact case limited hardware expansion. To address this issue, especially to allow for the installation of a hard disk, the case was changed to a slimline tower.
Lira AT
The new Lira AT was released at about the same time as the Lira XT Tower, with a similar looking slimline tower case. Lira AT was a IBM PC AT compatible, equipped with a 80286 CPU, 1MB of RAM, a EGA compatible video adapter, two 3.5" floppy drives and a 40MB hard disk. Serial production of this model started in December 1989.
Lira 386
The Lira 386, based on a 80386 CPU, was ready for production by 1990.
References
IBM PC compatibles | Lira 512 | [
"Technology"
] | 565 | [
"Computing stubs",
"Computer hardware stubs"
] |
51,770,542 | https://en.wikipedia.org/wiki/Honor%208 | The Honor 8 is a smartphone made by Huawei under their Honor sub-brand. It is a successor of the Huawei Honor 7 within the Huawei Honor series.
Specifications
Hardware
The Honor 8 is a smartphone made by Honor, a sub-brand of the Huawei Group, as part of the Huawei Honor series. It has an eight-core HiSilicon Kirin 950 processor, a Mali-T880 MP4 GPU, and a 3000 mAh (typical) battery. The phone comes with 32 or 64 gigabytes (GB) of storage and 4 GB LPDDR4 RAM. It has a , 2.5D glass liquid-crystal display (LCD) with 1080×1920 pixel resolution and "multilayer optical filming" to catch and reflect light.
The phone's dual 12 megapixel (MP) camera setup is flush to the phone's reverse glass panel. One of the rear cameras has a lens to capture details, and the other has an RGB sensor to record color data. The two resulting images are then merged. The camera app has a "Wide Aperture" mode, among others, which allows users to adjust the focus and depth of field after a photograph has been taken. The Honor 8 also has a forward-facing 8 MP camera.
Other features include an earpiece with built-in notification LED, a fingerprint sensor on the phone's back side, an infrared port allowing the phone to act as a universal remote, dual SIM-card support in select versions, a USB 2.0 with Type-C interface connector, and QuickCharge support. In addition to scanning fingerprints, the fingerprint sensor serves as a customizable "smart button", enabling users to open apps or scroll up or down the screen. Users can also tap their knuckles on the screen to take screenshots or recordings, or draw letters to open specific applications.
The Honor 8 measures by by and weighs . It has an aluminum bezel, metal trim, and glass back. In China, Honor 8 is available in the following colors: midnight black, sapphire blue, sunrise gold, sakura pink, and pearl white. Some hardware versions are only available in select colors. In the United States, Honor 8 is available in midnight black, sapphire blue, and pearl white. In November 2016, Honor announced that sakura pink, which was initially available only in China, would be sold in Europe.
Software
The Honor 8 launched with Android Marshmallow with Honor's Emotion UI interface (EMUI 4.0).
On February 11, 2017, Honor began to officially roll out EMUI 5, which is based on Android Nougat, to the Honor 8. According to Honor, the Honor 8 was not supposed to receive Android Oreo due to hardware limitations. However, in 2018, Huawei announced that the Honor 8 will be getting the Android Oreo update. The final firmware update, which included Android Oreo was released September 2018.
Release
Honor 8 launched in China in July 2016. Registrations were accepted until July 18; sales began on July 19. Honor confirmed more than 5 million registrations, or indications of interest, within four days of the phone's launch in China.
Honor hosted launch events in San Francisco and Paris in August 2016 to debut the Honor 8 in the United States and Europe, respectively. The phone launched in the U.S. on August 16, becoming the first flagship model (and second overall, following the Honor 5X earlier in 2016) marketed by Honor in the country. The "unlocked" phone is compatible with GSM networks (AT&T and T-Mobile). Honor sells the phone directly to customers and select online retailers such as Amazon.com and Best Buy, rather than through wireless carriers. The sapphire blue model was exclusive to Best Buy for the first 60 days of the phone's availability in the United States.
Honor 8's launch in Sweden included a world record attempt to complete the highest smartphone livestream. On September 5, the phone was placed in a weather balloon at Swedish Space Corporation's Esrange Space Center and carried into the air. The record for highest smartphone livestream, which was verified by Guinness World Records, was achieved despite the weather balloon's failure to reach the goal.
Honor began accepting pre-orders in the Middle East region on August 24, 2016; sales started on September 1.
Sales volume of Honor 8 worldwide exceeded 1.5 million units within the first two months of its launch.
Promotion
According to Honor's president George Zhao, the brand's U.S. launch strategy replicates the successful campaign in China by highlighting Honor 8's "cool design, serious components, [and] appealing prices" and by targeting millennials. To appeal to younger users, Honor focuses on the phone's "unique" aesthetics, high-performing dual-lens cameras, and fingerprint sensor.
Gift card rebate offers were available to U.S. customers who pre-ordered the Honor 8 through the brand's website or select retailers by September 3. In addition to its standard one-year warranty, Honor has offered an extended warranty to fix glass covering damages during the first three months after purchase. Honor has also guaranteed continuous software updates for the Honor 8 for at least two years, in an attempt to attract consumers.
Reception
Alex Dobie of Android Central called the Honor 8 an appealing phone with a "less industrial" and "more elegant" appearance than its predecessor. Business Insider Jeff Dunn said of the phone and its price: "Huawei's newest phone looks great, feels great, and runs with aplomb. There's a sense of heft and flair to it that cannot come from something you'd call 'cheap. Cherlynn Low of the technology blog network Engadget complimented the phone's camera and design.
Honor 8 has been compared to the Samsung Galaxy S7 and iPhone. Fast Company Harry McCracken, who tested a "pre-release" version of the phone, was impressed and called the Honor 8 worthy competitor to the more expensive Samsung Galaxy S7. Matthew Miller of ZDNet appreciated the phone's appearance and value. He called the model a "fingerprint magnet", but opined, "phones like this are really going to make people question paying double for the latest Samsung Galaxy or Apple iPhone".
Honor 8 earned "editor's choice" awards from the aforementioned Android Central as well as from Tom's Guide and was named the year's best mobile phone in the "middle class" category by Ljud & Bild. The Honor 8 also made it onto Android Police's list of the six best midrange smartphones of 2016, standing alongside the Moto Z Play, the OnePlus 3 and 3T, ZTE Axon 7, and BlackBerry DTEK60.
See also
List of Huawei phones
Honor (brand)
Honor 8x
Huawei Nova 3i
Huawei Mate 9
Huawei Mate 10
Huawei Mate 10 Lite
Huawei Mate 20
References
External links
(August 16, 2016, Android Authority)
(August 17, 2016, Engadget)
Huawei Honor
Mobile phones with multiple rear cameras
Mobile phones introduced in 2016
Discontinued flagship smartphones
Mobile phones with infrared transmitter | Honor 8 | [
"Technology"
] | 1,482 | [
"Discontinued flagship smartphones",
"Flagship smartphones"
] |
64,463,469 | https://en.wikipedia.org/wiki/Basic%20Number%20Theory | Basic Number Theory is an influential book by André Weil, an exposition of algebraic number theory and class field theory with particular emphasis on valuation-theoretic methods. Based in part on a course taught at Princeton University in 1961–62, it appeared as Volume 144 in Springer's Grundlehren der mathematischen Wissenschaften series. The approach handles all 'A-fields' or global fields, meaning finite algebraic extensions of the field of rational numbers and of the field of rational functions of one variable with a finite field of constants. The theory is developed in a uniform way, starting with topological fields, properties of Haar measure on locally compact fields, the main theorems of adelic and idelic number theory, and class field theory via the theory of simple algebras over local and global fields. The word `basic’ in the title is closer in meaning to `foundational’ rather than `elementary’, and is perhaps best interpreted as meaning that the material developed is foundational for the development of the theories of automorphic forms, representation theory of algebraic groups, and more advanced topics in algebraic number theory. The style is austere, with a narrow concentration on a logically coherent development of the theory required, and essentially no examples.
Mathematical context and purpose
In the foreword, the author explains that instead of the “futile and impossible task” of improving on Hecke's classical treatment of algebraic number theory, he “rather tried to draw the conclusions from the developments of the last thirty years, whereby locally compact groups, measure and integration have been seen to play an increasingly important role in classical number theory”. Weil goes on to explain a viewpoint that grew from work of Hensel, Hasse, Chevalley, Artin, Iwasawa, Tate, and Tamagawa in which the real numbers may be seen as but one of infinitely many different completions of the rationals, with no logical reason to favour it over the various p-adic completions. In this setting, the adeles (or valuation vectors) give a natural locally compact ring in which all the valuations are brought together in a single coherent way in which they “cooperate for a common purpose”. Removing the real numbers from a pedestal and placing them alongside the p-adic numbers leads naturally – “it goes without saying” to the development of the theory of function fields over finite fields in a “fully simultaneous treatment with number-fields”. In a striking choice of wording for a foreword written in the United States in 1967, the author chooses to drive this particular viewpoint home by explaining that the two classes of global fields “must be granted a fully simultaneous treatment […] instead of the segregated status, and at best the separate but equal facilities, which hitherto have been their lot. That, far from losing by such treatment, both races stand to gain by it, is one fact which will, I hope, clearly emerge from this book.”
After World War II, a series of developments in class field theory diminished the significance of the cyclic algebras (and, more generally, the crossed product algebras) which are defined in terms of the number field in proofs of class field theory. Instead cohomological formalism became a more significant part of local and global class field theory, particularly in work of Hochschild and Nakayama, Weil, Artin, and Tate during the period 1950–1952.
Alongside the desire to consider algebraic number fields alongside function fields over finite fields, the work of Chevalley is particularly emphasised. In order to derive the theorems of global class field theory from those of local class field theory, Chevalley introduced what he called the élément idéal, later called idèle, at Hasse's suggestion. The idèle group of a number field was first introduced by Chevalley in order to describe global class field theory for infinite extensions, but several years later he used it in a new way to derive global class field theory from local class field theory. Weil mentioned this (unpublished) work as a significant influence on some of the choices of treatment he uses.
Reception
The 1st edition was reviewed by George Whaples for Mathematical Reviews and Helmut Koch for Zentralblatt. Later editions were reviewed by Fernando Q. Gouvêa for the Mathematical Association of America and by Koch for Zentralblatt; in his review of the second edition Koch makes the remark "Shafarevich showed me the first edition in autumn 1967 in Moscow and said that this book will be from now on the book about class field theory". The coherence of the treatment, and some of its distinctive features, were highlighted by several reviewers, with Koch going on to say "This book is written in the spirit of the early forties and just this makes it a valuable source of information for everyone who is working about problems related to number and function fields."
Contents
Roughly speaking, the first half of the book is modern in its consistent use of adelic and idèlic methods and the simultaneous treatment of algebraic number fields and rational function fields over finite fields. The second half is arguably pre-modern in its development of simple algebras and class field theory without the language of cohomology, and without the language of Galois cohomology in particular. The author acknowledges this as a trade-off, explaining that “to develop such an approach systematically would have meant loading a great deal of unnecessary machinery on a ship which seemed well equipped for this particular voyage; instead of making it more seaworthy, it might have sunk it.” The treatment of class field theory uses analytic methods on both commutative fields and simple algebras. These methods show their power in giving the first unified proof that if K/k is a finite normal extension of A-fields, then any automorphism of K over k is induced by the Frobenius automorphism for infinitely many places of K. This approach also allows for a significantly simpler and more logical proof of algebraic statements, for example the result that a simple algebra over an A-field splits (globally) if and only if it splits everywhere locally. The systematic use of simple algebras also simplifies the treatment of local class field theory. For instance, it is more straightforward to prove that a simple algebra over a local field has an unramified splitting field than to prove the corresponding statement for 2-cohomology classes.
Chapter I
The book begins with Witt’s formulation of Wedderburn’s proof that a finite division ring is commutative ('Wedderburn's little theorem'). Properties of Haar measure are used to prove that `local fields’ (commutative fields locally compact under a non-discrete topology) are completions of A-fields. In particular – a concept developed later – they are precisely the fields whose local class field theory is needed for the global theory. The non-discrete non-commutative locally compact fields are then division algebras of finite dimension over a local field.
Chapter II
Finite-dimensional vector spaces over local fields and division algebras under the topology uniquely determined by the field's topology are studied, and lattices are defined topologically, an analogue of Minkowski's theorem is proved in this context, and the main theorems about character groups of these vector spaces, which in the commutative one-dimensional case reduces to `self duality’ for local fields, are shown.
Chapter III
Tensor products are used to study extensions of the places of an A-field to places of a finite separable extension of the field, with the more complicated inseparable case postponed to later.
Chapter IV
This chapter introduces the topological adele ring and idèle group of an A-field, and proves the `main theorems’ as follows:
both the adele ring and the idèle group are locally compact;
the A-field, when embedded diagonally, is a discrete and co-compact subring of its adele ring;
the adele ring is self dual, meaning that it is topologically isomorphic to its Pontryagin dual, with similar properties for finite-dimensional vector spaces and algebras over local fields.
The chapter ends with a generalized unit theorem for A-fields, describing the units in valuation terms.
Chapter V
This chapter departs slightly from the simultaneous treatment of number fields and function fields. In the number field setting, lattices (that is, fractional ideals) are defined, and the Haar measure volume of a fundamental domain for a lattice is found. This is used to study the discriminant of an extension.
Chapter VI
This chapter is focused on the function field case; the Riemann-Roch theorem is stated and proved in measure-theoretic language, with the canonical class defined as the class of divisors of non-trivial characters of the adele ring which are trivial on the embedded field.
Chapter VII
The zeta and L-functions (and similar analytic objects) for an A-field are expressed in terms of integrals over the idèle group. Decomposing these integrals into products over all valuations and using Fourier transforms gives rise to meromorphic continuations and functional equations. This gives, for example, analytic continuation of the Dedekind zeta-function to the whole plane, along with its functional equation. The treatment here goes back ultimately to a suggestion of Artin, and was developed in Tate's thesis.
Chapter VIII
Formulas for local and global different and discriminants, ramification theory, and the formula for the genus of an algebraic extension of a function field are developed.
Chapter IX
A brief treatment of simple algebras is given, including explicit rules for cyclic factor sets.
Chapters X and XI
The zeta-function of a simple algebra over an A-field is defined, and used to prove further results on the norm group and groupoid of maximal ideals in a simple algebra over an A-field.
Chapter XII
The reciprocity law of local class field theory over a local field in the context of a pairing of the multiplicative group of a field and the character group of the absolute Galois group of the algebraic closure of the field is proved. Ramification theory for abelian extensions is developed.
Chapter XIII
The global class field theory for A-fields is developed using the pairings of Chapter XII, replacing multiplicative groups of local fields with idèle class groups of A-fields. The pairing is constructed as a product over places of local Hasse invariants.
Third edition
Some references are added, some minor corrections made, some comments added, and five appendices are included, containing the following material:
A character version of the (local) transfer theorem and its extension to the global transfer theorem.
Šafarevič's theorem on the structure of Galois groups of local fields using the theory of Weil groups.
Theorems of Tate and Sen on the Herbrand distribution.
Examples of L-functions with Grössencharacter.
Editions
References
Mathematics books
Algebraic number theory | Basic Number Theory | [
"Mathematics"
] | 2,241 | [
"Algebraic number theory",
"Number theory"
] |
64,466,240 | https://en.wikipedia.org/wiki/Icons%20of%20Mathematics | Icons of Mathematics: An Exploration of Twenty Key Images is a book on elementary geometry for a popular audience. It was written by Roger B. Nelsen and Claudi Alsina, and published by the Mathematical Association of America in 2011 as volume 45 of their Dolciani Mathematical Expositions book series.
Topics
Each of the book's 20 chapters begins with an iconic mathematical diagram, and discusses an interrelated set of topics inspired by that diagram, including results in geometry, their proofs and visual demonstrations, background material, biographies of mathematicians, historical illustrations and quotations, and connections to real-world applications.
The topics include:
The geometry of circles and triangles, star polygons, Platonic solids, and figurate numbers
The Pythagorean theorem, Thales's theorem on right triangles in semicircles, and geometric interpretations of the arithmetic mean, geometric mean, and harmonic mean
Dido's problem on surrounding as large an area as possible with a given perimeter, and curves of constant width
Tessellations, polygon triangulations, and rep-tiles
Similar figures and spirals
The mathematics of the yin and yang symbol and other self-complementary shapes, and of tatami arrangements.
Audience and reception
Reviewer E. J. Barbeau recommends the book to high-school level mathematics students and teachers. Cheryl McAllister suggests it as auxiliary material for both high school and general-audience college mathematics courses, and Hans-Wolfgang Henn adds that it also makes enjoyable light reading for professional mathematicians.
References
Elementary geometry
Popular mathematics books
2011 non-fiction books
Mathematical Association of America | Icons of Mathematics | [
"Mathematics"
] | 329 | [
"Elementary mathematics",
"Elementary geometry"
] |
64,466,245 | https://en.wikipedia.org/wiki/Matrix%20factorization%20of%20a%20polynomial | In mathematics, a matrix factorization of a polynomial is a technique for factoring irreducible polynomials with matrices. David Eisenbud proved that every multivariate real-valued polynomial p without linear terms can be written as AB = pI, where A and B are square matrices and I is the identity matrix. Given the polynomial p, the matrices A and B can be found by elementary methods.
Example
The polynomial x2 + y2 is irreducible over R[x,y], but can be written as
References
External links
A Mathematica implementation of an algorithm to matrix-factorize polynomials
Polynomials
Algebra
Polynomial factorization algorithms | Matrix factorization of a polynomial | [
"Mathematics"
] | 131 | [
"Polynomials",
"Algebra"
] |
64,467,255 | https://en.wikipedia.org/wiki/Sunkoshi%20Marin%20Diversion%20Project | 'Sunkoshi Marin Diversion Project' (सुनकोशी मरिन डाइभर्सन आयोजना) is one of the National Pride Projects being developed by Ministry of Energy, Water Resources and Irrigation (Nepal). The project got status of National Pride Projects in 20 January 2020.
The project is an inter-basin transfer project to transfer water from Sunkoshi River to the Marin Khola, a tributary of Bagmati River. The flow will be discharged to the Bagmati Irrigation System to irrigate additional 122,000 ha of land in Rautahat, Dhanusha, Mahottari, Sarlahi and Bara.
The design flow of the project is 67 m3/s. The intake has a 12 m high diversion dam in Sunkoshi river. The flow is transferred via 13.3 km long tunnel. The project also has a power station to generate 38.62 MW of electricity. The powerhouse is located in Kamalamai municipality.
The project cost is NPR 37.2 billion for irrigation and NPR 46.19 billion for hydro-electricity.
See also
List of National Pride Projects of Nepal
References
Irrigation in Nepal
Interbasin transfer
National Pride Projects | Sunkoshi Marin Diversion Project | [
"Environmental_science"
] | 244 | [
"Hydrology",
"Interbasin transfer"
] |
64,473,976 | https://en.wikipedia.org/wiki/Mark%20Petrokovets | Mark Iosifovich Petrokovets (; 10 April 1937 – 18 November 2006) was a Soviet and Belarusian scientist prominent in the fields of tribology, the study of frictional interaction between surfaces, and well known for his classical influential handbooks "Introduction to Tribology" and "Friction and wear in polymer-based materials".
Biography
Mark Petrokovets was born to a Jewish family in Gomel, Belarus, on April 10, 1937. He graduated with MS in mathematics from Francysk Skaryna Gomel State University in 1959. He spent 3 years as a high school teacher in Brest region. In 1963, he was invited to Gomel Institute of Mathematics and Computer Science (it was later renamed to Metal–Polymer Research Institute of National Academy of Sciences of Belarus), where he spent all his life, working as a lab technician, senior mechanic, junior, senior, lead and chief researcher. He obtained PhD degree from Latvian Academy of Sciences in 1970. The main focus of his research was the mechanics of the actual area of touch with viscoelastic contact. He received Doctor of Science degree in 1993. His doctoral thesis were dedicated to developing models of discrete contact in relation to metal-polymer friction nodes.
For many years, Mark Petrokovets was a member of the editorial board of the international scientific journals "Friction and Wear” and “Materials, Technology, Tools”. He was a member of Society of Tribologists and Lubrication Engineers (STLE).
Research
Mark Petrokovets’ scientific work was associated with geometric and thermal calculations of metal-polymer gears, the development of methods for calculating thin-layer plain bearings, assessment of the deformity of polymers. He developed original approaches to solving the problems of tribology, which can include
the problems of modeling discrete friction contact,
the development of calculated methods of determining the actual area of touch,
the creation of an adequate model of friction and wear of polymers and composite materials.
In the last decade of his life, Mark Petrokovets was actively engaged in the problems of discrete contact at the nanometer scale. He is the author of more than 100 scientific works and publications, including 7 monographs. Mark Petrokovets was a co-author of the collective monograph "Tribology. Research and applications: The experience of the USA and ex-USSR", published simultaneously in English and Russian.
Selected publications
Introduction to Tribology. N. K. Myshkin, C. K. Kim, M. I. Petrokovets. Cheong Moon Gak Publishers, Seoul, 1997.
Friction and wear in polymer-based materials. V. A. Bely, A. I. Sviridenok, M. I. Petrokovets, V. G. Savkin. Pergamon Press, Oxford, 1982. .
Tribology of polymers: adhesion, friction, wear, and mass-transfer. M. I. Petrokovets, N. K. Myshkin, A. V. Kovalev. Tribology International, vol.38, p. 910-921.
Tribology. Principles and applications (in Russian). N. K. Myshkin, M. I. Petrokovets. Gomel, IMMS NANB, 2002.
See also
Belarusian encyclopedia, vol.12, Minsk, 2000, p. 332
The path to science: Notable doctors and professors - graduates of Gomel Universities // Issue II, F. Skaryna Gomel State University, 2005.
References
Belarusian scientists
Soviet scientists
Nanotechnologists
Tribologists
People from Gomel
1937 births
2006 deaths
Soviet mechanical engineers | Mark Petrokovets | [
"Materials_science"
] | 754 | [
"Nanotechnology",
"Tribologists",
"Nanotechnologists",
"Tribology"
] |
64,474,040 | https://en.wikipedia.org/wiki/Hiroshi%20Fujita | (born 7 December 1928 in Osaka) is a retired Japanese mathematician who worked in partial differential equations. He obtained his Ph.D. at the University of Tokyo, under the supervision of Tosio Kato.
Mathematical contributions
His most widely cited paper, published in 1966, studied the partial differential equation
and showed that there is a "threshold" value for which implies the existence of nonconstant solutions which exist for all positive and all real values of the variables. By contrast, if is between and then such solutions cannot exist. This paper initiated the study of similar and analogous phenomena for various parabolic and hyperbolic partial differential equations. The impact of Fujita's paper is described by the well-known survey articles of Levine (1990) and Deng & Levine (2000).
In collaboration with Kato, Fujita applied the semigroup approach in evolutionary partial differential equations to the Navier–Stokes equations of fluid mechanics. They found the existence of unique locally defined strong solutions under certain fractional derivative-based assumptions on the initial velocity. Their approach has been adopted by other influential works, such as Giga & Miyakawa (1985), to allow for different assumptions on the initial velocity. The full understanding of the smoothness and maximal extension of such solutions is currently considered as a major problem of partial differential equations and mathematical physics.
Selected publications
Tosio Kato and Hiroshi Fujita. On the nonstationary Navier-Stokes system. Rend. Sem. Mat. Univ. Padova 32 (1962), 243–260.
Hiroshi Fujita and Tosio Kato. On the Navier-Stokes initial value problem. I. Arch. Rational Mech. Anal. 16 (1964), 269–315.
Hiroshi Fujita. On the blowing up of solutions of the Cauchy problem for . J. Fac. Sci. Univ. Tokyo Sect. I 13 (1966), 109–124.
Mathematical theory of sedimentation analysis (book)
Functional-Analytic Methods for Partial Differential Equations (1990, Springer), Proceedings of a Conference and a Symposium held in Tokyo, Japan, July 3–9, 1989. Edited by Hiroshi Fujita, Teruo Ikebe and Shige T. Kuroda.
Proceedings of the Ninth International Congress on Mathematical Education, Edited by Hiroshi Fujita et al.
References
Japanese mathematicians
1928 births
People from Osaka
Mathematical analysts
University of Tokyo alumni
Living people | Hiroshi Fujita | [
"Mathematics"
] | 486 | [
"Mathematical analysis",
"Mathematical analysts"
] |
64,474,493 | https://en.wikipedia.org/wiki/IPhone%2012 | The iPhone 12 and iPhone 12 Mini (stylized and marketed as iPhone 12 mini) are smartphones developed and marketed by Apple Inc. They are the fourteenth-generation iPhones, succeeding the iPhone 11. They were unveiled at a virtually held Apple Special Event at Apple Park in Cupertino, California, on October 13, 2020, alongside the "premium flagship" iPhone 12 Pro and iPhone 12 Pro Max and HomePod Mini. Pre-orders for the iPhone 12 started on October 16, 2020, and the phone was released in most countries on October 23, 2020, alongside the iPhone 12 Pro and fourth-generation iPad Air. Pre-orders for the iPhone 12 Mini began on November 6, 2020, and the phone was released on November 13, 2020, alongside the iPhone 12 Pro Max.
The major upgrades over the iPhone 11 include the addition of a Super Retina XDR OLED as opposed to the Liquid Retina LED-backlit LCD IPS panel on the iPhone 11 and XR, 5G support, the introduction of MagSafe, Apple A14 Bionic system on a chip (SoC) and high-dynamic-range video Dolby Vision 4K up to 30 fps. The iPhone 12 and iPhone 12 Mini, like the iPhone 12 Pro and iPhone 12 Pro Max, are the first iPhone models from Apple to no longer include a power adapter or EarPods headphones found in prior iPhone models; however, a USB-C to Lightning cable is included; this change was retroactively applied to other iPhone models sold by Apple, such as the iPhone XR, iPhone 11 and the second-generation iPhone SE.
Design
The iPhone 12 and 12 Mini is the first major redesign since the iPhone X. It features a chassis with flat edges, similar to the iPhone 4 and iPhone 5 designs, as well as the iPad Pro since 2018, and the 4th-generation iPad Air, which was also released in 2020. The notch size is similar to previous iPhone models, despite speculation about a reduction in width. The borders around the display are thinner by 35% than any previous model. The new design also comes with a ceramic-hardened front glass, marketed as Ceramic Shield, while the back retains the previous generation Dual-Ion Exchange strengthened glass.
On April 20, 2021, at Apple's Special Event “Spring Loaded”, Apple revealed a new purple color option which became available on April 30, 2021.
The iPhone 12 and 12 Mini are available in six colors: Black, White, Product Red, Green, Blue, and Purple.
Specifications
Hardware
The iPhone 12 and iPhone 12 Mini use Apple's six-core A14 Bionic processor, which contains a next-generation neural engine. They both have three internal storage options: 64, 128, and 256 GB. Both also carry an IP68 water and dust resistance rating along with dirt and grime, and is water-resistant up to six meters (20 feet) for 30 minutes. However, the manufacturer warranty does not cover liquid damage to the phone.
The iPhone 12 series are the first iPhone models to be supplied from launch without EarPods or a wall adapter, which Apple says was done to reduce carbon emissions and waste since most users already own them. Apple also claims 70% more boxes can fit on a pallet given the smaller box, and thus further reducing emissions. A USB-C to Lightning cord is still included. This change also applies retroactively to all other iPhone models still in production. To comply with French law regarding wireless device radiation and health which requires phones to be bundled with and promote use of hands-free accessories by children under 14, iPhone models will still include EarPods in this market.
A magnetic connector known as MagSafe is introduced on the iPhone 12 models, allowing accessories such as cases and charging cords to be attached to the rear of the device. Accessories can also be stacked together.
The devices support 5G cellular communications. This allows upload speeds of up to 200 Mbit/s and download speeds of up to 4 Gbit/s. However, only models sold in the U.S. support the fastest mmWave technology; those sold elsewhere in the world, including Canada, support only sub-6 GHz frequency bands. A new feature called Smart Data Mode enables 5G only when necessary to preserve battery life.
Displays
The iPhone 12 features a display with Super Retina XDR OLED technology at a resolution of 2532 × 1170 pixels and a pixel density of about 460 ppi. The iPhone 12 Mini features a display with the same technology at a resolution of 2340 × 1080 pixels, and a pixel density of about 476 ppi. Both phones have a peak brightness of 1200 nits when viewing HDR content equivalent to the iPhone 12 Pro, and normal brightness of 625 nits. Both phones also use an improved glass-ceramic covering called Ceramic Shield which is co-developed with Corning Inc. Apple describes it as having "4 times better drop performance" and being "tougher than any smartphone glass".
Batteries
The iPhone 12 has a 10.78 Wh (2,815 mAh) battery, a slight decrease from the 11.91 Wh (3,110 mAh) battery found in the iPhone 11 and identical to the battery found in the iPhone 12 Pro. The iPhone 12 Mini has a 8.57 Wh (2,227 mAh) battery. Like previous iPhones, the battery is not user-replaceable..Drawback of iPhone 12 is the speaker damage.Apple also approve it's their manufacturing defect.|archieve-https://support.apple.com/en-in/iphone-12-and-iphone-12-pro-service-program-for-no-sound-issues. </ref>
Chipsets
Both the iPhone 12 and 12 Mini have the Apple A14 Bionic, the first ARM-based smartphone system-on-a-chip (SoC) manufactured on the 5 nm process node. However, unlike previous years, they are not the first Apple devices to receive the newest A-series processor, with the fourth-generation iPad Air being the first. Both phones use Qualcomm's Snapdragon X55 5G modem.
Speaker
iPhone have a small amount of defect in speker's specifically in iPhone 12 and iPhone 12 Pro which can cause damage in ear speaker.iPhone admit that it was a manufacturing defect.And some of iPhone 12 users may experience sound issues due to a component that might fail on the receiver module. Affected devices were manufactured between October 2020 and April 2021.|archieve- https://support.apple.com/en-in/iphone-12-and-iphone-12-pro-service-program-for-no-sound-issues. </ref>
Cameras
Both phones have two rear 12-megapixel cameras: wide and ultra-wide. The wide camera is a 26 mm full-frame equivalent with an f/1.6 aperture which captures 27% more light than the f/1.8 aperture in the iPhone 11 and a seven-element lens. The ultra-wide camera is a 13 mm full-frame equivalent with an f/2.4 aperture and a five-element lens.
All cameras now support Night Mode for both photo and time-lapse video at full resolution. Smart HDR has been improved thanks to Smart HDR 3. This iPhone model is the first capable of shooting 10-bit high dynamic range Dolby Vision 4K video at up to 30 fps which allows for greater brightness and deeper shadows.
The front-facing, TrueDepth camera features a 12-megapixel camera with an f/2.2 aperture. This model also added Night Mode to the front-facing camera.
Sensors
The iPhone 12 and 12 Mini include mostly the same sensors found on prior iPhone models going back to the iPhone X. These include an accelerometer, gyroscope, barometer, proximity sensor, ambient light sensor, and a digital compass. The devices also include the Face ID sensor for biometric authentication.
Software
Both phones originally shipped with iOS 14. The devices come with the stock iOS apps, such as Safari, Weather, and Messages, and they include Siri, the personal assistant in iOS. They received iOS 15 on September 20, 2021, iOS 16 on September 12, 2022, iOS 17 on September 18, 2023, and most recently, iOS 18 on September 16, 2024.
Reception
The iPhone 12 received largely positive reviews. The Verge called it a "beautiful, powerful, and incredibly capable device", praising the new design reminiscent of the iPhone 5, the speed of the A14 Bionic processor, its 5G capabilities, addition of the OLED display like on the high end iPhones, combined with much slimmer bezels than previous iPhone models and improved battery life over iPhone 11. Engadget also gave the iPhone 12 a positive review, praising the MagSafe wireless charging and accessories magnetic attachment as well as the redesigned camera system, a greatly improved display like in its Pro counterparts.
iPhone 12 was the third best-selling and was the most popular model globally in Q2 2021.
Apple was criticized for the continued reliance on Face ID as the sole biometric option to unlock the device, which is incompatible with face masks. iOS 14.5 allowed the use of a paired Apple Watch to unlock the phone while wearing a mask, while iOS 15.4 allows unlocking with a mask on, without an Apple Watch. The third-generation iPhone SE is the only iPhone currently produced by Apple that supports Touch ID, an alternative unlocking option that is compatible with face masks. All models can still use a passcode to log in.
The iPhone 12 mini has received more mixed reviews. Some praised the phone for being a new small phone, while others criticized the price and inferior battery life compared to the full-size 12 (although the battery life of the iPhone 12 mini is longer than that of the second-generation iPhone SE).
"OLED-gate"
Within two weeks after its public release, a thread was started at Apple Support Communities describing a problem with the iPhone 12 and iPhone 12 Pro OLED panel black pixels not shutting off completely in black scenes, resulting in what was described as "ugly glowing". A considerable number of users have since posted replies reporting the same problem, photos and videos have been shared online demonstrating the issue. As of January 2021, Apple has not yet made an official statement.
EarPods and power adapter controversy
Apple no longer includes either EarPods or a power adapter in the boxes of all iPhone 12 and 12 Pro models, claiming that it is an environmental initiative and no longer including them would reduce e-waste and permit smaller iPhone boxes, allowing more devices to be transported simultaneously to decrease its carbon footprint. The boxes only include a USB-C to Lightning cable, incompatible with the existing USB-A power adapters that Apple previously supplied with its devices. Users can still use their existing USB-A power adapters and cables but must purchase a USB-C power adapter sold separately to enable fast charging.
The iPhone 12 was sold in France with EarPods as the law required that smartphones be bundled with “hands-free kits” or a “headset” in order to protect children aged 14 and younger from electromagnetic radiation.
In December 2020, a Brazilian consumer rights watchdog Procon-SP Foundation requested Apple to provide proof that not including chargers is beneficial to the environment. The watchdog argues that Apple removing the charger is harming consumers and wants to force the company to include one as it claims the charger is an essential component.
The Verge reported the reason power adapters and EarPods are no longer included could be to offset the increased cost of 5G components. These new components are reported to cost 30% more than their predecessors.
Repairability concerns
iFixit and Australian YouTuber Hugh Jeffreys discovered that a number of key components such as the cameras would malfunction or display warnings if they are replaced with new ones or those taken from an otherwise identical donor unit. Internal Apple documents also mention that, beginning with the iPhone 12 and in subsequent models, authorized technicians would have to run the phones through an internal System Configuration tool to reprogram repaired units in order to account for hardware changes. While Apple has yet to comment on the issue, the inability to replace key system components have raised concerns about right to repair and planned obsolescence. However, the iPhone 12 Mini does not have this issue. Apple later addressed the issue with the release of iOS 14.4, which displays a warning message if the phone detects an unpaired camera module but otherwise allows for full functionality.
Electromagnetic radiation concerns
In September 2023, the French watchdog agency notified Apple that sales of the iPhone 12 must be halted in France due to the device exceeding the legal specific absorption rate for consumer electronics. The agency also requested that Apple must recall all iPhone 12s that have been produced in order to meet safety regulations. However, this coincided with the release of the iPhone 15 models where Apple also discontinued the iPhone 12 globally.
Despite the move however, France's digital minister did emphasize the iPhone 12's radiation levels remained well below the threshold deemed harmful by scientific studies. Even Apple, "...disputed the findings and said the device complies with regulations..." [Regulations | source 39]. This highlighted a discrepancy between the agency's tests and real-world phone usage scenarios.
See also
Comparison of smartphones
History of the iPhone
List of iPhone models
Timeline of iPhone models
Explanatory notes
References
External links
– official site
Mobile phones introduced in 2020
Mobile phones with 4K video recording
Mobile phones with multiple rear cameras
Products and services discontinued in 2023
Discontinued flagship smartphones | IPhone 12 | [
"Technology"
] | 2,819 | [
"Discontinued flagship smartphones",
"Flagship smartphones"
] |
64,474,587 | https://en.wikipedia.org/wiki/Burt%27s%20solar%20compass | Burt's solar compass or astronomical compass/sun compass is a surveying instrument that makes use of the Sun's direction instead of magnetism. William Austin Burt invented his solar compass in 1835. The solar compass works on the principle that the direction to the Sun at a specified time can be calculated if the position of the observer on the surface of the Earth is known, to a similar precision. The direction can be described in terms of the angle of the Sun relative to the axis of rotation of the planet.
This angle is made up of the angle due to latitude, combined with the angle due to the season, and the angle due to the time of day. These angles are set on the compass for a chosen time of day, the compass base is set up level using the spirit levels provided, and then the sights are aligned with the Sun at the specified time, so the image of the Sun is projected onto the cross grating target. At this point the compass base will be aligned true north–south. It is then locked in place in this alignment, after which the sighting arms can be rotated to align with any landmark or beacon, and the direction can be read off the verniers as an angle relative to true north.
This device avoided the problems of the normal magnetic compass used by surveyors, which displayed erratic readings when in a locality of high iron ore content and inconsistent and unknown local magnetic variation. The instrument was found to be so accurate that it was the choice of the United States government when surveying public lands, state boundaries, and railroad routes. It won awards from various organizations and was used by surveyors from the nineteenth into the twentieth century.
History
Burt became a United States deputy surveyor in 1833 and began surveying government land for a territory northwest of the Ohio River. By 1834, he and his surveying crew were surveying territory in the lower peninsula of Michigan. He was surveying land in the upper peninsula of Michigan by 1835 to be used by new settlers. Here he found that his sensitive compass that worked by magnetic field attraction was fluctuating erratically because of the iron ore deposits in the area that interfered with the field. Burt devised an instrument attachment that relied on sunlight, not magnetism, to find true north. He called the resulting product a True Meridian Finding instrument. It overcame the vagaries of the surveyor's compass caused by interference from iron ore deposits in a local land mass district.
Burt first used the solar instrument in his Michigan surveys. He found large outcropping deposits of iron ore at Negaunee in Marquette County in his later 1844 survey of the upper peninsula of the state of Michigan. This would become known as the Marquette Iron Range. His crew found small deposits of iron ore in the state's lower peninsula at about the same time. His accidental discovery of these iron deposits in Michigan contributed much to America's Industrial Revolution. The Calumet and Hecla Mine of Michigan's Copper Country was discovered with Burt's instrument, and it became the leading copper producer in the world.
Burt's solar compass uses the location of the Sun with astronomical tables and enables surveyors to run more accurate lines, saving them much time. Burt had a model of his instrument built in 1835 by William James Young, a professional instrument maker. He then submitted this solar compass to a committee at the Franklin Institute in Philadelphia. They examined its characteristics and then awarded Burt twenty dollars in gold and the John Scott Medal for its technology. Burt patented his solar compass innovation on February 25, 1836. It has since been referred to as Burt's solar compass or astronomical compass. He used it in the 1836–1837 season to survey the fifth principal meridian in Iowa.
Burt improved on the instrument over the years with certain mechanics to make it simpler to operate with better accuracy. In 1840, he received another patent on his improved solar compass. He resubmitted the updated version of the instrument to the Franklin Institute where they found it to be more accurate and easier to use than the first version. The Federal Land Office general surveyor E. S. Haines examined Burt's surveying instrument in December 1840 and reported in a 1841 letter that with its four-year experience in surveying it was found to be superior in technology to the normal compass then used by most surveyors. The Commissioner of the Federal Land Office sent letters to surveyors general throughout the United States saying Burt's compass was being manufactured by the surveyor Henry Ware and available for purchase.
Burt in 1849 went to Washington with his son to apply for a renewal of his solar compass original patent of 1835 that was about to expire. The land commissioner committee, which consisted of senators from Michigan and other states, recognizing the value of Burt's solar compass in public land surveys, persuaded him to forego renewal and petition congress for suitable advance compensation. Burt did as was suggested believing that he would be compensated appropriately. However, the compensation indicated did not materialize in Burt's lifetime or at any time thereafter. Since there was no patent on Burt's solar compass after 1850, instrument makers manufactured and sold "Burt's solar compass" to surveyors as a commercial product. The inventor spent thousands of dollars to perfect his instrument, but only received eighty dollars in sales of his tool for his labors.
In the preface to his Key to Solar Compass and Surveyor's Companion (1858) by his associate William S. Young, Burt refers to the many requests for such a book on how to use his solar compass. He explains that the common surveyor's compass had problems with the true meridian at different localities. It also had problems from day to day with different readings from that expected as a constant or from previous readings. It was determined that a magnetic compass was prone to interference from the local attraction of iron ore. A more accurate guide for the surveyor was desired, so the solar compass was created by Burt.
Surveyor Bela Hubbard noted in 1845 that with Burt's solar compass they could survey a straight line through iron-rich country, which would have been an impossible task using the normal compass instrument. The original impetus for Burt's solar compass was for use where the old fashion compass was vulnerable to large land iron deposits that made unusable readings. It was then found to be superior in general to the common compass, even when local iron ore deposits were not a problem. A solar compass attachment to the surveyor's transit was still the recommended method for obtaining the true north direction as instructed in the 1973 surveyor's manual of the US Bureau of Land Management. The instrument was widely adopted for surveying land in the United States and mandatory for government surveying from the mid-nineteenth century until the year 2000, when the satellite Global Positioning System technology became the preferred method of surveying.
Description
Principle of operation
Surveyors can locate true north by viewing the Sun or other astronomical objects like stars or the Moon, which have a direction from any given point on the surface of the Earth. It can be calculated precisely for a given date and time, and is not influenced by local variations in the magnetic field due to local deposits of minerals such as iron ore. Burt's instrument allows surveyors to determine the true north direction in reference to the Sun rather than being influenced by the Earth's magnetic field. It is made of brass and therefore has no magnetic influence on a compass needle, as it was originally a small attachment to a standard surveyor's common compass.
Application of the solar compass requires knowledge of the apparent motion of the Sun around the Earth, relative to the Earth as the center of the frame of reference, and more specifically, relative to the position of the instrument when set up to use in a survey. An understanding of the latitudinal and seasonal declination and the longitudinal variation with time of day are necessary, as the compass has specific sub-assemblies to take each of these variables into account.
At the Earth's equator at the equinoxes, the Sun has no seasonal declination, rises due east, and sets due west. At noon the Sun is at its highest point, directly overhead. It is at its lowest point at midnight, and appears to move in the plane of the equator. At locations away from the equator, the noon altitude of the Sun will be reduced by the angle of the Earth's local horizontal to the polar axis the latitude so at a latitude of 10° south or north, the noon altitude will be at the equinoxes. This angle is known to the surveyor and is set on the latitude arc of the instrument so that with the base leveled, and the compass aligned with true north, the axis of the hour arc will be parallel to the polar axis.
The rotational axis of the Earth is tilted from the perpendicular to the plane of its orbit around the Sun. This angle causes the altitude angle of the Sun to vary with the seasons by an amount which depends on the direction of the misalignment. It varies predictably throughout the year, increasing and decreasing smoothly at a calculable rate, and is constant for everywhere on Earth at the same time. This value is also known to the surveyor, as it is published in a set of tables in an almanac. A correction for this declination is made on the declination arc of the compass, which is mounted to rotate on the polar axis on top of the latitude arc, as the latitude and declination angles are additive. The angle of the Sun due to time of day is set on the hour angle arc, which is perpendicular to the polar axis. This angle is calculated from longitude and GMT, also tabulated for the convenience of surveyors and navigators, as the calculations are tedious to perform in the field, and any error could have extensive effects.
Assuming a spherical Earth, if a straight line were drawn from the rising to the setting sun, and from the sun at noon and at midnight on the equinoxes, both of these lines would pass through the Earth's center and the equator would intersect these lines. This is not so when the sun has north or south declination because its apparent motion will be at an angle to the equatorial plane, equal to the amount of the sun's declination north or south, so that when the sun has north or south declination, and the Earth is regarded as the center of its revolutions, the line from the Sun to the center of the Earth describes a cone.
This conical motion of the Sun can also be illustrated by the dished spokes of the wheel of a covered wagon with the rim representing the Sun's apparent path, the hub representing the Earth, and the spokes being lines drawn from the Sun's path. It may be seen that a line drawn from the Sun to the Earth's center would pass north or south of the equator, equal in degree to its declination north or south. The instrument has an equatorial movement, with a mechanical attachment for sighting a star as a reference.
Construction and operation
Burt's solar compass consists of a main plate mounted to the tripod stand and leveled using the two orthogonal attached spirit levels. It carries a common compass needle box, having divisions for the north end of the needle of about 36 degrees, with a vernier to read the needle's variation, and the three adjustable arcs of the solar instrument: one is set for the latitude of the location; another for the seasonal declination of the Sun; and the third for the hour of the day adjusted for longitude of the location. The sights to set alignment by the Sun are mounted on the movable arm of the declination arc and have a small lens for focusing an image of the Sun's disc on the target grating. The upper plate is aligned with the Sun and remains stationary after polar alignment, while bearings are taken with the sights on the lower plate. The lower plate carries the surveying sights and can be rotated relative to the upper plate, and may be clamped in any position to the upper plate. There is a graduated ring on the lower plate which displays the relative rotation between the north-aligned top plate and the surveying sight-line on the bottom plate, and has verniers to allow precise reading of the angle.
The latitude arc is attached perpendicular to the upper plate. The hour arc is fixed perpendicular to the movable upper part of the latitude arc, and the declination arc swivels on a polar axis over and perpendicular to the declination arc. The positions of the arcs can be finely adjusted by screws and the angles read with a vernier. Clamp screws are provided where necessary to lock the components in place. At one end of the adjustable limb of the declination arc there are small lenses set up to focus an image of the Sun's disc onto a target plate inscribed with parallel pairs of perpendicular lines to frame the image when correctly aligned.
The operation is as follows:
Set the Sun's declination for that day, obtained by means of tables, on a scale attached perpendicular to the time arc.
Set the latitude of the location on a scale in the alidade.
Set the approximate local time on the arc that rotates on a polar axis.
Orient the instrument, while it remains level, so the image of the Sun appears between two scribed lines on the screen opposite to the lens. The time dial is finely adjusted to bring the image between a second pair of scribed lines perpendicular to the first pair. The main axis of the upper plate will then point to the pole.
The pinnula (sighting vanes) may then be aligned with a terrestrial object and its bearing read from the angle scale.
The magnetic declination may be read from a compass attached to the base plate.
Reception
Burt improved the instrument over the years and it won awards from various organizations for its technology as being simple, rugged, inexpensive, reliable and accurate and was used by surveyors from the nineteenth into the twentieth century. In 1851, he exhibited his latest version at the Great Exhibition World's Fair in London. There it was examined and endorsed by scholar John Herschel. Burt received a prize from the fair for his compass instrument design. He then received another medal for his simpler, more accurate version by jurors of Astronomical Instruments with a personal compliment by Albert Edward, Prince of Wales, on October 15, 1851, at Hyde Park, London, England.
This instrument was invented to get away from the highly variable and unreliable readings given by the common compass of the day in a locality with a magnetic field anomaly caused by large iron ore deposits. The instrument was found to be so accurate that it was specified by the United States government for surveying public lands, state boundaries, and railroad routes. Burt's instrument was used to survey 75 per cent of the public lands of the United States, consisting of nearly a billion acres. It had saved the government millions of dollars because of its general inexpensive price tag and the accuracy of the survey. It surveyed mineral lands in many states, including Michigan, Wisconsin, Minnesota, Arkansas, and Colorado. Its project expenditure to survey a section of land was only a fraction of what it used to cost before his invention. An example of comparison was the boundary line between Iowa and Minnesota that was surveyed before at with the use of the old-fashioned instruments, while with Burt's solar compass it was only .
See also
References
Sources
Burt, John, History of Solar Compass Invented by William A. Burt (1878).
Kuno Gross The Bagnold sun-compass, history and utilization Books on demand 2011
Further reading
R. A. Bagnold and W. J. Harding King, "Journeys in the Libyan Desert 1929 and 1930", The Geographical Journal, Vol. 78, No. 6 (Dec., 1931), pp. 524, 526–535
Tuttle, Charles Richard, General History of the state of Michigan with biographical sketches, R. D. S. Tyler & Co., Detroit Free Press Company, 1873
W. B. Kennedy Shaw, "Desert Navigation: Some Experiences of the Long Range Desert Group", The Geographical Journal, V.102, Number 5, 1943, pp. 253–258 Published by The Royal Geographical Society
External links
suncompass.co.uk
sun compass
sun compass
Abrams sun compass
Abrams sun compass on YouTube
Theory of sun compass
MkII sun compass
Desert Storm sun compass
American inventions
Navigational equipment
Orientation (geometry) | Burt's solar compass | [
"Physics",
"Mathematics"
] | 3,333 | [
"Topology",
"Space",
"Geometry",
"Spacetime",
"Orientation (geometry)"
] |
54,585,837 | https://en.wikipedia.org/wiki/Sodium%20magnesium%20sulfate | Sodium magnesium sulfate is a double sulfate of sodium and magnesium. There are a number of different stoichiometries and degrees of hydration with different crystal structures, and many are minerals.
Members include:
Blödite or bloedite: sodium magnesium sulfate tetrahydrate Na2Mg(SO4)2•4H2O
Disodium magnesium disulfate decahydrate Na2Mg(SO4)2•10H2O
Disodium magnesium disulfate hexadecahydrate Na2Mg(SO4)2•16H2O
Na2SО4·MgSO4·2.5H2O
Konyaite Na2Mg(SO4)2•5H2O
Löweite Na12Mg7(SO4)13•15H2O.
Vanthoffite Na6Mg(SO4)4
Na2Mg2(SO4)3 langbeinite form stable from 569.2 to 624.7°C
Na2Mg2(SO4)3 quenched monoclinic form
Na2Mg3(SO4)4 orthorhombic form
Na2Mg(SO4)2 triclinic form
Salts containing other anions in addition to sulfate
Na2Mg3(OH)2(SO4)4•4H2O
Tychite hexasodium dimagnesium sulfate tetracarbonate Na6Mg2SO4(CO3)4
Uklonskovite NaMgSO4F•2H2O
References
External links
Sulfates
Magnesium compounds
Sodium compounds
Double salts | Sodium magnesium sulfate | [
"Chemistry"
] | 337 | [
"Sulfates",
"Double salts",
"Salts"
] |
54,588,474 | https://en.wikipedia.org/wiki/XO-6b | XO-6b is a transiting exoplanet, a hot Jupiter, orbiting the star XO-6 around 760 light years (230 parsecs) away from Earth. It was discovered in 2016 by the XO planet search team.
Physical properties
XO-6b is one of the puffiest planets ever discovered, with a maximum mass of 4.4 times of Jupiter. It is over twice as wide, making it one of the largest exoplanets ever found (see list of largest exoplanets). Later estimates, however, make it around two times the mass of Jupiter.
XO-6b has a tight orbit, which means a year on it is only about 4 days. XO-6 is slightly more than one-tenth as far from its host star as Mercury is to the sun.
XO-6
XO-6b orbits XO-6, a faint 10th magnitude star in the constellation Camelopardalis. Due to its magnitude, this star is too faint to be seen with the naked eye, but can be seen with a telescope. XO-6 is a F-type main-sequence star with about 1.5 times the mass of the Sun. It is also radiating 4 times as bright, and is almost twice the size of the Sun. It is also hotter, with a temperature of 6720 kelvins, which gives it the typical hue of an F-type star. Unlike most other stars of its kind, XO-6 rotates rapidly at a rate of 43 km/s.
References
Further reading
Exoplanets discovered in 2016
Transiting exoplanets
Hot Jupiters
Camelopardalis | XO-6b | [
"Astronomy"
] | 346 | [
"Camelopardalis",
"Constellations"
] |
54,589,355 | https://en.wikipedia.org/wiki/NGC%203642 | NGC 3642 is a spiral galaxy in the constellation Ursa Major. The galaxy has a low-ionization nuclear emission-line region. It is located at a distance of circa 30 million light years from Earth, which, given its apparent dimensions, means that NGC 3642 is about 50,000 light years across. The galaxy is characterised by an outer pseudoring, which was probably formed after the accretion of a gas rich dwarf galaxy.
Structure
NGC 3642 is a spiral galaxy without a bar. In the nucleus there is a supermassive black hole with an estimated mass of 26-31 million M⊙, based on the intrinsic velocity dispersion as measured by the Hubble Space Telescope, or 15 million M⊙, based on the bulge luminosities in near-infrared Ks-band.
Around the nucleus, a one-armed spiral forms a ring, and it is possible that it leads material towards the nucleus. The nucleus is surrounded by an inner flocculent spiral. The outer part of the spiral forms a pseudoring that extends for about half a circle. The outer part of the spiral is warped, while its main part features an ordinary differentially rotating disk. The HI gas is also warped and extends further on the western side.
Nearby galaxies
The galaxy belongs to the NGC 3642 group (also known as the NGC 3610 group), a galaxy group that also includes NGC 3610, NGC 3619, NGC 3669, NGC 3674 and NGC 3683. Other nearby galaxies include NGC 3440, NGC 3445, NGC 3458, NGC 3543 and NGC 3613.
Gallery
References
External links
Unbarred spiral galaxies
Ursa Major
3642
06385
34889 | NGC 3642 | [
"Astronomy"
] | 351 | [
"Ursa Major",
"Constellations"
] |
54,589,443 | https://en.wikipedia.org/wiki/Anatoly%20Zayats | Anatoly V. Zayats is a British experimental physicist of Ukrainian origin known for his work in nanophotonics, plasmonics, metamaterials and applied nanotechnology. He is currently a Chair in Experimental Physics and the head of the Photonics & Nanotechnology Group at King's College London. He is a co-director of the London Centre for Nanotechnology and the London Institute for Advanced Light Technologies
Education
Zayats was educated at the Moscow Institute of Physics and Technology.
Career and research
Zayats's current research interests are in areas of nanophotonics, plasmonics and metamaterials, optical spin-orbit effects and topological photonics, nonlinear and ultrafast optics and spectroscopy, photo-active nanomaterials, scanning probe microscopy and optical properties of surfaces, thin films, semiconductors and low-dimensional structures.
Zayats may be most widely-known for his contributions to the development of nano-optics of surface plasmon polaritons, nonlinear plasmonics and nanophotonics, hyperbolic and epsilon-near-zero metamaterials and their applications in ultrasensitive bio- and chemical sensing and nonlinear optics, plasmonic hot-electrons for photochemical transformations as well photonic spin-orbit effects in nanophotonics for directional routing of guided modes, directional optical forces and discovery of photonic skyrmions.
Zayats currently leads the Engineering and Physical Sciences Research Council programme grant 'New perspectives in photocatalysis and near-surface chemistry: catalysis meets plasmonics' (2022-2028) (CPLAS), investigating light-driven energy-conversion at the nanoscale for stimulating chemical transformations. This is a multidisciplinary collaborative project between King's College London, Imperial College London and the UK Catalysis Hub. CPLAS is the third EPSRC programme grant that Zayats has led; Active Plasmonics ran from 2009 to 2015. and Reactive Plasmonics, from 2015 to 2021.
Zayats is the holder of the ERC Advanced Grants Integrated Plasmonic Metamaterials (2013-2018) and Integrating Complex Beams and Metasurfaces.(2018-2023).
In 2017, together with Stefan Maier (Imperial College London) and Franco Cacialli (UCL), he founded the London Institute for Advanced Light Technologies, a joint virtual research centre between King's College London, Imperial College London and University College London, focusing on the emerging topics in optical research, and in particular providing an interdisciplinary and collaborative environment and a framework for interactions with the photonic industry, and training for PhD students.
Zayats served as a member of the A*STAR Data Storage Institute's Scientific Advisory Board.
Zayats is a founding co-editor-in-chief of the SPIE-Chinese Laser Press journal Advanced Photonics.
Publications
Zayats's research has been published in leading peer reviewed scientific journals.
Awards and honours
2022 – Elected Member of Academia Europaea
2021 - Humboldt Prize
2018 - Distinguished Lecture in Transformative Science and Engineering (Nanjing University, China)
2014 - Fellow of the Royal Society of Chemistry (FRSC)
2013 - Royal Society Wolfson Research Merit Award
2012 - Fellow of SPIE
2008 - Fellow of The Optical Society
2006 - Fellow of the Institute of Physics (FInstP)
References
Academics of King's College London
British academics
British physicists
British people of Ukrainian descent
Living people
Ukrainian expatriates in the United Kingdom
Year of birth missing (living people)
Members of Academia Europaea | Anatoly Zayats | [
"Materials_science"
] | 743 | [
"Metamaterials scientists",
"Metamaterials"
] |
54,589,646 | https://en.wikipedia.org/wiki/Aequationes%20Mathematicae | Aequationes Mathematicae is a mathematical journal. It is primarily devoted to functional equations, but also publishes papers in dynamical systems, combinatorics, and geometry. As well as publishing regular journal submissions on these topics, it also regularly reports on international symposia on functional equations and produces bibliographies on the subject.
János Aczél founded the journal in 1968 at the University of Waterloo, in part because of the long publication delays of up to four years in other journals at the time of its founding.
It is currently published by Springer Science+Business Media, with Zsolt Páles of the University of Debrecen as its editor in chief. János Aczél remains its honorary editor in chief.
It is frequently listed as a second-quartile mathematics journal by SCImago Journal Rank.
References
Functional equations
Mathematics journals
Academic journals established in 1968 | Aequationes Mathematicae | [
"Mathematics"
] | 183 | [
"Mathematical analysis",
"Mathematical objects",
"Functional equations",
"Equations"
] |
54,589,726 | https://en.wikipedia.org/wiki/Bluetooth%20mesh%20networking | Bluetooth Mesh is a computer mesh networking standard based on Bluetooth Low Energy that allows for many-to-many communication over Bluetooth radio. The Bluetooth Mesh specifications were defined in the Mesh Profile and Mesh Model specifications by the Bluetooth Special Interest Group (Bluetooth SIG). Bluetooth Mesh was conceived in 2014 and adopted on .
Overview
Bluetooth Mesh is a mesh networking standard that operates on a flood network principle. It's based on the nodes relaying the messages: every relay node that receives a network packet that
authenticates against a known network key
is not in message cache
has a TTL ≥ 2
can be retransmitted with TTL = TTL - 1. Message caching is used to prevent relaying recently seen messages.
Communication is carried in the messages that may be up to 384 bytes long, when using Segmentation and Reassembly (SAR) mechanism, but most of the messages fit in one segment, that is 11 bytes. Each message starts with an opcode, which may be a single byte (for special messages), 2 bytes (for standard messages), or 3 bytes (for vendor-specific messages).
Every message has a source and a destination address, determining which devices process messages. Devices publish messages to destinations which can be single things / groups of things / everything.
Each message has a sequence number that protects the network against replay attacks.
Each message is encrypted and authenticated. Two keys are used to secure messages: (1) network keys – allocated to a single mesh network, (2) application keys – specific for a given application functionality, e.g. turning the light on vs reconfiguring the light.
Messages have a time to live (TTL). Each time message is received and retransmitted, TTL is decremented which limits the number of "hops", eliminating endless loops.
Architecture
Bluetooth Mesh has a layered architecture, with multiple layers as below.
Types of nodes
Nodes that support the various features can be formed into a particular mesh network topology.
Theoretical limits
The practical limits of Bluetooth Mesh technology are unknown. Some limits that are built into the specification include:
Mesh models
As of version 1.0 of Bluetooth Mesh specification, the following standard models and model groups have been defined:
Foundation models
Foundation models have been defined in the core specification. Two of them are mandatory for all mesh nodes.
Configuration Server (mandatory)
Configuration Client
Health Server (mandatory)
Health Client
Generic models
Generic OnOff Server, used to represent devices that do not fit any of the model descriptions defined but support the generic properties of On/Off
Generic Level Server, keeping the state of an element in a 16-bit signed integer
Generic Default Transition Time Server, used to represent a default transition time for a variety of devices
Generic Power OnOff Server & Generic Power OnOff Setup Server, used to represent devices that do not fit any of the model descriptions but support the generic properties of On/Off
Generic Power Level Server & Generic Power Level Setup Server, including a Generic Power Actual state, a Generic Power Last state, a Generic Power Default state and a Generic Power Range state
Generic Battery Server, representing a set of four values representing the state of a battery
Generic Location Server & Generic Location Setup Server, representing location information of an element, either global (Lat/Lon) or local
Generic User/Admin/Manufacturer/Client Property Server, representing any value to be stored by an element
Generic OnOff Client & Generic Level Client
Generic Default Transition Time Client
Generic Power OnOff Client & Generic Power Level Client
Generic Battery Client
Generic Location Client
Generic Property Client
Sensors
Sensor Server & Sensor Setup Server, representing a sensor device. Sensor device may be configured to return a measured value periodically or on request; measurement period (cadence) may be configured to be fixed or to change, so that more important value range is being reported faster.
Sensor Client
Time and scenes
Time Server & Time Setup Server, allowing for time synchronization in mesh network
Scene Server & Scene Setup Server, allowing for up to 65535 scenes to be configured and recalled when needed.
Scheduler Server & Scheduler Setup Server
Time Client, Scene Client & Scheduler Client
Lighting
Light Lightness Server & Light Lightness Setup Server, representing a dimmable light source
Light CTL Server, Light CTL Temperature Server & Light CTL Setup Server, representing a CCT or "tunable white" light source
Light HSL Server, Light HSL Hue Server, Light HSL Saturation Server & Light HSL Setup Server, representing a light source based on Hue, Saturation, Lightness color representation
Light xyL Server & Light xyL Setup Server, representing a light source based on modified CIE xyY color space.
Light LC (Lightness Control) Server & Light LC Setup Server, representing a light control device, able to control Light Lightness model using an occupancy sensor and ambient light sensor. It may be used for light control scenarios like Auto-On, Auto-Off and/or Daylight Harvesting.
Light Lightness Client, Light CTL Client, Light HSL Client, Light xyL Client & Light LC Client
Provisioning
Provisioning is a process of installing the device into a network. It is a mandatory step to build a Bluetooth Mesh network.
In the provisioning process, a provisioner securely distributes a network key and a unique address space for a device. The provisioning protocol uses P256 Elliptic Curve Diffie-Hellman Key Exchange to create a temporary key to encrypt network key and other information. This provides security from a passive eavesdropper.
It also provides various authentication mechanisms to protect network information, from an active eavesdropper who uses man-in-the-middle attack, during provisioning process.
A key unique to a device known as "Device Key" is derived from elliptic curve shared secret on provisioner and device during the provisioning process. This device key is used by the provisioner to encrypt messages for that specific device.
The security of the provisioning process has been analyzed in a paper presented during the IEEE CNS 2018 conference.
The provisioning can be performed using a Bluetooth GATT connection or advertising using the specific bearer.
Terminology used in the Bluetooth Mesh Model and Mesh Profile specifications
Destination: The address to which a message is sent.
Element: An addressable entity within a device.
Model: Standardized operation of typical user scenarios.
Node: A provisioned device.
Provisioner: A node that can add a device to a mesh network.
Relay: A node able to retransmit messages.
Source: The address from which a message is sent.
Implementations
Approved ("qualified") by Bluetooth SIG
Free and open-source software implementations
Free software and open source software implementations include the following:
The official (included in Linux kernel by Linus Torvalds in 2001) Linux Bluetooth protocol stack BlueZ, dual free-licensed under the GPL and the LGPL, supports Mesh Profile, from release version 5.47, by providing meshctl tool (deprecated) to configure mesh devices. Release version 5.53 introduced mesh-cfgclient tool for configuring mesh networks. BlueZ was approved as a "qualified" software package by Bluetooth SIG in 2005. BlueZ is not considered to be a qualified Bluetooth Mesh stack as Bluetooth Mesh is not listed in aforementioned qualification record as a supported profile.
Apache Mynewt NimBLE, free-licensed under the Apache License 2.0, supports Bluetooth Mesh from release version 1.2.0. It was qualified on with QDID 131934.
Zephyr OS Mesh, free-licensed under the Apache License 2.0, supports Bluetooth Mesh from release version 1.9.0. Zephyr OS Mesh 1.14.x was qualified on with QDID 139259.
See also
Cabir (computer worm)
BlackArch
Bluejacking
Bluebugging
Bluesnarfing
AirDrop
References
Bluetooth
Open standards
Mesh networking | Bluetooth mesh networking | [
"Technology"
] | 1,653 | [
"Wireless networking",
"Mesh networking",
"Bluetooth"
] |
54,590,122 | https://en.wikipedia.org/wiki/Chasing%20Coral | Chasing Coral is a 2017 American documentary film about a team of divers, scientists and photographers around the world who document the disappearance of coral reefs. Chasing Coral was produced by Exposure Labs and directed by Jeff Orlowski. It premiered at the 2017 Sundance Film Festival and was released globally on Netflix as a Netflix Original Documentary in July 2017. Jeff Orlowski has previously directed the movie Chasing Ice in 2012, which shares a similar plot to Chasing Coral.
Soundtrack
Saul Simon MacWilliams and Dan Romer composed the score for the film. Romer also co-wrote an original song, "Tell Me How Long", featuring Kristen Bell.
Reception
The film won the Audience Award for U.S. Documentary at the 2017 Sundance Film Festival.
References
External links
2017 films
2017 documentary films
2017 in the environment
2010s American films
2010s English-language films
American documentary films
Coral reefs
Documentary films about environmental issues
Documentary films about global warming
Documentary films about marine biology
Documentary films about photographers
Documentary films about water and the environment
English-language documentary films
Films scored by Dan Romer
Nature photography
Netflix original documentary films
Satellite Award–winning films | Chasing Coral | [
"Biology"
] | 223 | [
"Biogeomorphology",
"Coral reefs"
] |
54,590,538 | https://en.wikipedia.org/wiki/Stankoprom | Stankoprom () is a Russian designer and manufacturer of machine tools based in Moscow. It was established in 2013 on the initiative of the Ministry of Industry and Trade of Russia and Rostec State Corporation. as part as Russia's Import substitution strategy to reduce the country's reliance on foreign-made machine tools. It includes scientific centers as well as manufacturing plants. Stankoprom is part of the state-owned holding company Rostec, and it incorporates 14 machine tool manufacturers.
History
Stankoprom Holding was established in 2013 on the initiative of the Ministry of Industry and Trade of Russia and Rostec State Corporation
. Stankoprom is the parent organization of Rostec State Corporation.
Operation
Stankoprom JSC, within the framework of Rostec State Corporation, has the status of a center for technological audit of technological equipment purchased by the corporation's organizations, as well as ensuring centralized supplies of machine tool products to the corporation's enterprises.
In October 2014 the Russian government decided to appoint Stankoprom as an engineering competence center and the locomotive of the process of introducing domestic machine tools into production.
In 2014 Stankoprom and the representative company of the German Siemens concern in Russia and Central Asia signed an agreement on cooperation in the development of complex high-precision machines, as well as the implementation of technical re-equipment projects for domestic enterprises. According to Sergey Makarov, CEO of Stankoprom, one of the main goals of the company is to create a joint venture with Siemens "with the mandatory transfer of the most modern machine tool technologies and localization of production in Russia."
In 2018 from the report of Prosecutor General Yuri Chaika on the state of law and order in Russia, it became known that Stankoprom holding had not made a single domestic machine tool in four years, thereby disrupting the program to create serial production of machine tool products, for which a large amount of money was allocated. In this regard, a criminal case was opened on the fact of embezzlement by fraud in a large amount of budgetary funds.
In May 2021 it became known about the signing of an agreement on the localization of production of mobile turning and milling complexes that have no analogues in Russia between Stankoprom and the German manufacturer TRAWEMA GMBH. The agreement implied a full range of production — from design to production of finished products on the basis of the "VNIIINSTUMENT" ("ВНИИИНСТРУМЕНТ") enterprise, which is part of the Stankoprom holding. Due to the sanctions, this agreement was not implemented.
Structure
Structure of the company:
Scientific Centers
Vniialmaz
Vniiautogenmash
Vniti Em
Vniiinstrument
Mikron
Ulyanovsky Niat
Machine Manufacturing
Savelovo Machine Building Plant
Neftehimautomatika
Remos-PM
Tools Manufacturing
Instrumental Plant-PM
Trade and Engineering
Foreign Trade Enterprise Stankoimport (Llc)
Foreign Trade Enterprise Stankoimport (Ojsc)
RT-Stankoinstrument
References
External links
Official website
Rostec
Manufacturing companies established in 2013
Industrial machine manufacturers
Russian brands | Stankoprom | [
"Engineering"
] | 657 | [
"Industrial machine manufacturers",
"Industrial machinery"
] |
54,591,147 | https://en.wikipedia.org/wiki/Emanuel%20Gil-Av | Emanuel Gil-Av (Zimkin) (7 August 1916 – 24 March 1996) was an Israeli chemist. The main emphasis of his work constituted chiral chromatography for the analytical separation of enantiomers.
Life and Work
Emanuel Gil-Av was born 1916 in Pensa of Tzarist Russia. After the death of his father, a physician, the family moved first to Central Europe and in 1928 to Tel-Aviv, Israel, where Gil-Av attended High School. Gil-Av studied petroleum chemistry at the University of Strasbourg. In 1940 he escaped the German occupation to England where he worked at first in the chemical laboratory of Chaim Weizmann, followed by the Petrochemical Ltd. in Manchester. After World War II, he moved to Palestine and he joined the Daniel Sieff Institute in Rehovot which was later on to become the Weizmann Institute of Science. In 1951 he earned his PhD under the supervision of Ernst David Bergmann.
In his study of oil shale deposits, Gil-Av developed complex-forming stationary phases employing silver(I) ions for selective olefin separations by gas chromatography (GC). In co-operation with the centre of peptide chemistry at the Weizmann Institute of Science, he developed methods of the gas-chromatographic resolution of racemic α-amino acids. By coating a glass capillary column with the chiral stationary phase (CSP) N-trifluoroacetyl-L-isoleucine lauryl ester, Gil-Av et al. carried out in 1966 the first gas-chromatographic enantioseparation of racemic amino acids as N-trifluoroacetyl-O-alkyl derivatives. Many racemic compounds, amenable for enantioselective interaction via hydrogen bonding with the CSP, could be analytically enantioseparated by GC.
Further contributions of Gil-Av and associates are concerned with the use of chiral mobile phase additives (CMPAs) in liquid chromatography (LC), enantiomeric separation of helicenes by supramolecular LC, the temperature-dependent reversal of enantioselectivity by enthalpy-entropy compensation and non-linear effects leading to enantiomeric enrichment during chromatography on achiral stationary phases.
Literature
Emanuel Gil-Av, Present status of enantiomeric analysis by gas chromatography, J. Mol. Evol. 6 (1975) 131–144.
Nelu Grinberg: Emanuel Gil-Av (1916-1996): A man with a legacy, In: Chirality, 1998;10(5):372.
Volker Schurig: In Memoriam – Emanuel Gil-Av. In: Journal of High Resolution Chromatography 19 (1996) 462.
Volker Schurig: On the Centenary of Emanuel Gil-Av, Former Professor of the Weizmann Institute of Science and Pioneer of Enantioselective Chromatography, Isr. J. Chem. 56 (2016) 890–906.
References
1916 births
1996 deaths
People from Penza
People from Penzensky Uyezd
Jewish Russian scientists
Soviet emigrants to Mandatory Palestine
Analytical chemists
University of Strasbourg alumni
Academic staff of Weizmann Institute of Science | Emanuel Gil-Av | [
"Chemistry"
] | 701 | [
"Analytical chemists"
] |
54,592,282 | https://en.wikipedia.org/wiki/Minimum-Pairs%20Protocol | The minimum-pairs (or MP) is an active measurement protocol to estimate in real-time the smaller of the forward and reverse one-way network delays (OWDs). It is designed to work in hostile environments, where a set of three network nodes can estimate an upper-bound OWD between themselves and a fourth untrusted node. All four nodes must cooperate, though honest cooperation from the fourth node is not required. The objective is to conduct such estimates without involving the untrusted nodes in clock synchronization, and in a manner more accurate than simply half the round-trip time (RTT). The MP protocol can be used in delay-sensitive applications (such as placing content delivery network replicas) or for secure Internet geolocation.
Methodology
The MP protocol requires the three trusted network nodes to synchronize their clocks, and securely have access to their public keys, which could be achieved through a closed public key infrastructure (PKI) system. The untrusted node need not follow suit because it is not assumed to cooperate honestly. To estimate an upper bound to the smaller of the forward and reverse OWD between node A and the untrusted node X (see figure for notation), X first establishes an application-layer connection to all three nodes. This could be done transparently over the browser using, e.g., WebSockets. The three nodes then take turns in exchanging digitally-signed timestamps.
Assuming node A begins, it sends a signed timestamp to X. Node X forwards that message to the other two nodes. When the message is received, its receiving time is recorded. The receiving node then verifies the signature, and calculates the time it took the message to traverse the network from its originator to the recipient passing by the untrusted node. This is done by subtracting the timestamp in the message from the receiving time. Node B then repeats the process, followed by node C. After all three nodes have taken turns, they end-up with six delay estimates corresponding to the links:
A → X → B and B → X → A
A → X → C and C → X → A
B → X → C and C → X → B
To estimate the smaller of the forward and reverse OWDs on the three network links between A, B, C and X, the minimum of each such pairs above is taken (i.e., the larger is discarded). Each of the three pairs then represents an approximate to the smaller OWD on each link, which generates a system of three equations in three unknowns. Solving those simultaneously for a, b, and c (see figure) gives the delay estimate.
Numerical example
Assume the actual delays (e.g., in millisecond) to node X from nodes A, B and C and vice versa are as follows:
Those are the unknown delays. We need to estimate the smaller of the forward and reverse on each of the three links. In this example, the smaller is 5 ms, 4 ms, and 2 ms on the links between X and the three trusted nodes respectively (A, B, and C). When the nodes exchange the timestamp messages, they can only see the following:
A → X → B = 9 ms and B → X → A = 14 ms (9 ms is the smaller)
A → X → C = 9 ms and C → X → A = 8 ms (8 ms is the smaller)
B → X → C = 12 ms and C → X → B = 6 ms (6 ms is the smaller)
The system of equations thus becomes:
which results in estimates to the smaller OWDs of:
In this case, the absolute errors are , , and on all three links respectively. In comparison, the average RTT would calculate the OWD on all three links as 5.5 ms, 6 ms, and 3 ms, resulting in absolute errors of 0.5 ms, 2 ms, and 1 ms respectively. Therefore, the MP protocol is more accurate in this example.
Analysis
Injecting artificial delays by, e.g., holding onto the message for a little while instead of promptly forwarding it, enables the untrusted node to increase the estimated OWDs. The MP protocol can thus estimate an upper bound for OWDs on all three links collectively between the trusted nodes and the untrusted one. For example, if the estimated delays (forward or reverse) were 30 ms, 40 ms, and 50 ms, the actual cannot be 60 ms, 70 ms and 80 ms because that means the untrusted node managed to reduce all three together, which is hard to achieve since delays are bound by the physical characteristics of the transmission media. Note however that the untrusted node may in some case be able to reduce a subset of the links, but not all, by selectively delaying some of the links.
Compared to the average (i.e., RTT/2), the MP protocol never returns an estimate to the smaller of the forward and reverse OWD that is larger than that returned by the average method. Additionally, the probability distribution of absolute error for the MP protocol has been derived as a function of the underlying delay distribution. This is useful as it enables the calculation of expected error knowing the nature of delays on the links between the untrusted node and the trusted ones.
See also
Network delay
Trusted system
References
Telecommunication theory
Computer networking
Computer network security
Computational trust | Minimum-Pairs Protocol | [
"Technology",
"Engineering"
] | 1,120 | [
"Computer networking",
"Cybersecurity engineering",
"Computer engineering",
"Computer networks engineering",
"Computer science",
"Computer network security",
"Computational trust"
] |
54,593,711 | https://en.wikipedia.org/wiki/Int-Ball | The Int-Ball, also known as the JEM Internal Ball Camera, is a series of experimental, autonomous, self-propelled, and maneuverable ball cameras, deployed in the Japanese Kibō module of the International Space Station. The devices are intended to perform some of the photo-video documentation tasks aboard the ISS, reducing the workload of the station's crew. there have been two different Int-Ball cameras delivered to the station.
Internal Ball Camera
The first ball camera was delivered aboard SpaceX CRS-11 on June 4, 2017. The Int-Ball was designed by the Japan Aerospace Exploration Agency and is controlled and monitored by a team of JAXA ground controllers.
The Int-Ball naturally floats in the station's zero-gravity environment, allowing it to maneuver freely within the ISS. It weighs , and is in diameter. The device contains 3 reaction wheels and an array of 12 small electric fans mounted on the ball's outer surface. The unit shares many similarities with Earth-based drone motion control and drone camera systems. The Int-Ball's motion control system is capable of executing a rotation on any axis, and is also capable of overall movement in any general direction. The internal structural elements and outer body of the Int-Ball system were produced using 3D printing. The simulated "eyes", consisting of two blue light rings mounted on the exterior of the ball, represent the direction of the "gaze" of the Int-Ball, which is in fact a single camera lens situated in the approximate center of the two "eyes". The lights serve as a visual indicator that the camera is recording, and can also indicate errors by turning red. The device can be recharged via USB.
The Int-Ball system was designed with the hope of reducing or eliminating the amount of time spent by astronauts aboard the ISS in photo-video documentation activities, which have been estimated to consume approximately 10% of the astronauts' work time. The robotic photo-video documentation duties that the Int-Ball performs have been likened by some to the types of responsibilities that the fictional R2-D2 of the Star Wars movie series appeared to undertake.
Internal Ball Camera 2
The Int-Ball 2 is an updated version of the device. In addition to the floating camera ball, this system features a docking station.
See also
CIMON, floating robot deployed on the ISS by Airbus
Kirobo, interactive humanoid robot deployed on the ISS by JAXA
Robonaut2, semi-humanoid robot deployed on the ISS by NASA
References
JAXA
International Space Station
Space photography and videography
2017 robots | Int-Ball | [
"Astronomy"
] | 522 | [
"Outer space",
"Space photography and videography"
] |
54,593,972 | https://en.wikipedia.org/wiki/Steroid%20reductase | Steroid reductases are reductase enzymes that are involved in steroid biosynthesis and metabolism. They include:
5α-Reductase
5β-Reductase
See also
Steroidogenic enzyme
References
Oxidoreductases | Steroid reductase | [
"Chemistry"
] | 54 | [
"Oxidoreductases",
"Bioinorganic chemistry"
] |
54,594,268 | https://en.wikipedia.org/wiki/Apscaviroid | Apscaviroid is a genus of ssRNA viroids that belongs to the family Pospiviroidae.
Taxonomy
References
External links
ICTV Report: Pospiviroidae
Viroids
Virus genera | Apscaviroid | [
"Biology"
] | 42 | [
"Virus stubs",
"Viruses"
] |
54,594,294 | https://en.wikipedia.org/wiki/TACK | TACK is a group of archaea, its name an acronym for Thaumarchaeota (now Nitrososphaerota), Aigarchaeota, Crenarchaeota (now Thermoproteota), and Korarchaeota, the first groups discovered. They are found in different environments ranging from acidophilic thermophiles to mesophiles and psychrophiles and with different types of metabolism, predominantly anaerobic and chemosynthetic. TACK is a clade that is sister to the Asgard branch that gave rise to the eukaryotes. It has been proposed that the TACK clade be classified as Crenarchaeota and that the traditional "Crenarchaeota" (Thermoproteota) be classified as a class called "Sulfolobia", along with the other phyla with class rank or order. After including the kingdom category into ICNP, the only validly published name of this group is kingdom Thermoproteati (Guy and Ettema 2024).
Classification
Thermoproteota (formerly Crenarchaeota). It is the best known edge and the most abundant archaea in the marine ecosystem. They were previously called sulfobacteria because of their dependence on sulfur and are important as carbon fixers. There are hyperthermophiles in hydrothermal vents and other groups are the most abundant at depths of less than 100 m.
"Aigarchaeota". It is a phylum proposed from the genome of the candidate species Caldiarchaeum subterraneum found deep within a gold mine in Japan. Genomic sequences of this group have also been found in geothermal environments, both terrestrial and marine.
"Geoarchaeota". It includes thermophilic organisms that live in acidic environments reducing ferric iron. Alternatively it has been proposed that this and earlier group actually belong to the phylum Nitrososphaerota.
Nitrososphaerota (formerly Thaumarchaeota). It includes mesophilic or psychrophilic organisms (medium and low temperatures), of ammonia-oxidant chemolytoautotrophic metabolism (nitrifying) and that can play an important role in biochemical cycles, such as the nitrogen and carbon cycles.
"Bathyarchaeota". It is abundant in the sediments of the seabed with a shortage of nutrients. At least some lineages develop through homoacetogenesis, a type of metabolism hitherto thought unique to bacteria.
"Korarchaeota". They have only been found in hydrothermal environments and in low abundance. They seem diversified at different phylogenetic levels according to temperature, salinity (fresh or marine water) and geography.
Phylogeny
The relationships are roughly as follows:
Eocyte hypothesis
The eocyte hypothesis proposed in the 1980s by James Lake suggests that eukaryotes emerged within the prokaryotic eocytes.
One piece of evidence supporting a close relationship between TACK and eukaryotes is the presence of a homolog of the RNA polymerase subunit Rbp-8 in Thermoproteota but not in Euryarchaea.
See also
List of Archaea genera
References
Archaea taxa | TACK | [
"Biology"
] | 689 | [
"Archaea",
"Archaea taxa"
] |
54,594,340 | https://en.wikipedia.org/wiki/NGC%207075 | NGC 7075 is an elliptical galaxy located about 290 million light-years away in the constellation of Grus. NGC 7075 was discovered by astronomer John Herschel on September 4, 1834. It is classfied a radio galaxy.
NGC 7075 contains a Fanaroff-Riley class I radio source called PKS 2128-388. It has an unresolved core component. Its eastern radio jet, is found to have faint emission which extends out by ≈1.9 kpc from its nucleus. A CO disc is found in NGC 7075 but unresolved. According to Atacama Large Millimeter Array observations, a hole is present in the gas distribution, indicating gas disc disturbance.
IC 5105 Group
According to A. M. Garcia, NGC 7075 is part of the IC 5105 group (also known as LGG 445). This group of galaxies contains at least 19 members. The other galaxies in the group are: NGC 7057, NGC 7060, NGC 7072, NGC 7087, NGC 7110, NGC 7130, IC 5105, IC 5105A, IC 5128, IC 5139, and eight galaxies in the ESO catalogue.
See also
List of NGC objects (7001–7840)
Radio galaxy
M87
NGC 7016
References
External links
Elliptical galaxies
Radio galaxies
Grus (constellation)
7075
66895
Astronomical objects discovered in 1834 | NGC 7075 | [
"Astronomy"
] | 291 | [
"Grus (constellation)",
"Constellations"
] |
54,594,383 | https://en.wikipedia.org/wiki/Perfect%20obstruction%20theory | In algebraic geometry, given a Deligne–Mumford stack X, a perfect obstruction theory for X consists of:
a perfect two-term complex in the derived category of quasi-coherent étale sheaves on X, and
a morphism , where is the cotangent complex of X, that induces an isomorphism on and an epimorphism on .
The notion was introduced by for an application to the intersection theory on moduli stacks; in particular, to define a virtual fundamental class.
Examples
Schemes
Consider a regular embedding fitting into a cartesian square
where are smooth. Then, the complex
(in degrees )
forms a perfect obstruction theory for X. The map comes from the composition
This is a perfect obstruction theory because the complex comes equipped with a map to coming from the maps and . Note that the associated virtual fundamental class is
Example 1
Consider a smooth projective variety . If we set , then the perfect obstruction theory in is
and the associated virtual fundamental class is
In particular, if is a smooth local complete intersection then the perfect obstruction theory is the cotangent complex (which is the same as the truncated cotangent complex).
Deligne–Mumford stacks
The previous construction works too with Deligne–Mumford stacks.
Symmetric obstruction theory
By definition, a symmetric obstruction theory is a perfect obstruction theory together with nondegenerate symmetric bilinear form.
Example: Let f be a regular function on a smooth variety (or stack). Then the set of critical points of f carries a symmetric obstruction theory in a canonical way.
Example: Let M be a complex symplectic manifold. Then the (scheme-theoretic) intersection of Lagrangian submanifolds of M carries a canonical symmetric obstruction theory.
Notes
References
See also
Behrend function
Gromov–Witten invariant
Differential topology
Symplectic geometry
Hamiltonian mechanics
Smooth manifolds | Perfect obstruction theory | [
"Physics",
"Mathematics"
] | 385 | [
"Theoretical physics",
"Classical mechanics",
"Hamiltonian mechanics",
"Topology",
"Differential topology",
"Dynamical systems"
] |
54,594,690 | https://en.wikipedia.org/wiki/Gil%20Chaverri%20Rodr%C3%ADguez | Gil Chaverri Rodríguez (March 15, 1921, in Heredia, Costa Rica – May 27, 2005, in San José, Costa Rica) was a Costa Rican chemist and physicist. Chaverri created an original arrangement of the periodic table of chemical elements, published in 1952 in the Journal of Chemical Education. His arrangement of the periodic table was based on the electronic structure of each element, and was used in Costa Rican schools.
Childhood and early education
José Gil Chaverri Rodriguez was born in Heredia, Costa Rica on March 15, 1921, to José Joaquín Chaverri Zúñiga and María Josefa Rodríguez Solera. His family later moved to San José, where he attended primary school at Escuela Buenaventura Corrales (1928-1933) and secondary school at the Colegio Seminario de San José (Seminary School, 1934-1937) and the Liceo de Costa Rica (1938-1939).
University education
At the University of Costa Rica he earned a degree in agricultural engineering from the Faculty of Agronomy in 1944.
He went from there to Cornell University, where he received a Masters in Sciences in 1945.
He also studied engineering at the University of Costa Rica from 1955-1957.
In 1959, he received a scholarship from the National Academy of Sciences of the United States, which enabled him to attend Iowa State University. There he completed a Ph.D. thesis on the Application of the solubility-product principle to the dissolution of phosphate rock in 1962.
In addition to his scientific studies, he was a gifted linguist, reading and speaking English, French and German by the time he finished high school, and later studying Russian, Latin, Greek, Italian and Portuguese.
Career
Gil Chaverri Rodriguez began teaching in 1942, at the Colegio Seminario.
From 1946-1978 he taught chemistry at the University of Costa Rica, where he held a number of position. He was head of the Chemical Laboratory of the Ministry of Agriculture and Livestock (Laboratorio Químico del Ministerio de Agricultura y Ganadería) from 1948-1956. He was the founding Director of the Center for Agronomic Research (Centro de Investigación Agronómica, CIA) from 1956-1960, and Dean of the Faculty of Sciences and Letters from 1965-1971.
He published both educational and scientific works, including textbooks such as
Ley de acción de masas y sus aplicaciones ("Law of mass action and its applications", 1950).
From 1978 to 1999 he taught at the Escuela Autónoma de Ciencias Médicas. He retired in 1999.
Periodic Table
Chaverri Rodríguez created an arrangement of the Periodic Table of Chemical Elements, published in 1952 in the Journal of Chemical Education. His arrangement is based on the electronic structure of the elements, which allows for the placement of the lanthanide and actinide series in a logical sequence according to their atomic number. It has been used for teaching chemistry in Costa Rican schools.
Personal
Chaverri Rodríguez was married to Antonieta Polini Castro, with whom he lived in the San Antonio district of the Desamparados canton of San José. They had seven children. His wife predeceased him by two years.
Gil Chaverri Rodríguez died at the Hospital México, San José, Costa Rica on May 27, 2005. Although he had suffered from Parkinson's disease for some time, the immediate cause of death was a heart attack.
References
1921 births
2005 deaths
Costa Rican chemists
People involved with the periodic table
Cornell University alumni
Costa Rican expatriates in the United States
Iowa State University alumni | Gil Chaverri Rodríguez | [
"Chemistry"
] | 743 | [
"Periodic table",
"People involved with the periodic table"
] |
54,595,901 | https://en.wikipedia.org/wiki/Androsterone%20sulfate | Androsterone sulfate, also known as 3α-hydroxy-5α-androstan-17-one 3α-sulfate, is an endogenous, naturally occurring steroid and one of the major urinary metabolites of androgens. It is a steroid sulfate which is formed from sulfation of androsterone by the steroid sulfotransferase SULT2A1 and can be desulfated back into androsterone by steroid sulfatase.
See also
Androsterone glucuronide
Steroid sulfate
C19H30O5S
References
External links
Metabocard for Androsterone Sulfate (HMDB02759) - Human Metabolome Database
5α-Reduced steroid metabolites
Androgen esters
Androstanes
Human metabolites
Ketones
Sulfate esters | Androsterone sulfate | [
"Chemistry",
"Biology"
] | 181 | [
"Ketones",
"Biotechnology stubs",
"Functional groups",
"Biochemistry stubs",
"Biochemistry"
] |
54,596,568 | https://en.wikipedia.org/wiki/NGC%206939 | NGC 6939 is an open cluster in the constellation Cepheus. It was discovered by William Herschel in 1798. The cluster lies 2/3° northwest from the spiral galaxy NGC 6946. The cluster lies approximately 4,000 light years away and it is over a billion years old.
Observation
NGC 6939 is located near the border of the constellations Cepheus and Cygnus, at the southwest corner of Cepheus. The open cluster is located two degrees southwest of Eta Cephei and 2/3° northwest from the spiral galaxy NGC 6946, which has visual magnitude 8.7. They appear as two patches of haze with 10x50 binoculars. NGC 6939 can be seen and glimpsed with 7x35 binoculars where as 25x200 binoculars are required to start resolve the cluster. The cluster can be glimpsed with 4 inches telescope and is resolved at x72 magnification. NGC 6939 is included in the Herschel 400 Catalogue.
Characteristics
NGC 6939 is an old open cluster, located 400 parsec above the galactic plane and 8.400 parsec away from the galactic centre. With the use of photometric studies, the age of the cluster was estimated to be between 1,0 and 1,3 billion years!, using as sample 638 stars within the field. The metallicity of the cluster is slightly subsolar (-0.19±0.09).
Some of its members are variable stars: a study in 1998 led to the discovery of six variable stars among the red giants of the cluster, with two of which are Algol type and V466 Cephei appears to be a W Ursae Majoris type. A further study in 2004 identified further 10 variables near the cluster, five of which were W Ursae Majoris type and one RR Lyrae.
References
External links
Open clusters
Cepheus (constellation)
6939
Astronomical objects discovered in 1798 | NGC 6939 | [
"Astronomy"
] | 393 | [
"Constellations",
"Cepheus (constellation)"
] |
54,596,960 | https://en.wikipedia.org/wiki/Androstenediol%20sulfate | Androstenediol sulfate, also known as androst-5-ene-3β,17β-diol 3β-sulfate, is an endogenous, naturally occurring steroid and a urinary metabolites of androstenediol. It is a steroid sulfate which is formed from sulfation of androstenediol by steroid sulfotransferase and can be desulfated back into androstenediol by steroid sulfatase.
See also
Steroid sulfate
C19H30O5S
References
Androgen esters
Androstanes
Secondary alcohols
Human metabolites
Sulfate esters | Androstenediol sulfate | [
"Chemistry",
"Biology"
] | 138 | [
"Biochemistry stubs",
"Biotechnology stubs",
"Biochemistry"
] |
54,597,460 | https://en.wikipedia.org/wiki/Hyperkin | Hyperkin is an American video game peripheral manufacturer and distributor, founded in 2006, based in Los Angeles, California. They distribute accessories for major gaming consoles, in addition to creating clone consoles that play retro games with modern resolutions and on modern devices, most notably the RetroN series of clone consoles. As with most other NES clones, Hyperkin's NES clones (excluding the Retron5 as it utilizes software emulation) suffer from imperfect sound due to a design flaw in the sound hardware.
In 2011, the company became the exclusive distributor of Dance Battle VS. In addition, they released the Remotext, a Blu-ray remote control and keypad game controller hybrid for the PlayStation 3, and a battery-expanding attachment for the Nintendo 3DS called the Powerplus. They also created the Supaboy, a handheld Super Nintendo. In 2016 Hyperkin released the Supaboy S featuring a bigger 4.3" screen displaying in the 16:9 aspect ratio, making games look stretched. The Supaboy S also introduces an NTSC/PAL switch, improving compatibility with PAL-region games. In 2018, Hyperkin released the Supaboy SFC, which is an upgrade of the Supaboy S with buttons resembling the Super Famicom and PAL SNES. The Supaboy SFC also has the ability to switch between stretch 16:9 and letterboxed 4:3 aspect ratios by holding down the brightness button.
In 2014, the company released the Retron 5, an Android-based console with five cartridge ports that allowed for play of five different types of retro games.
The Retron 5 utilizes code violating the GPL and several non-commercial licenses. As it is an emulator, the Retron5 does not have the sound problems present in Hyperkin's other consoles.
In 2017, the company released the Smart Boy, a smartphone add-on that allows the device to play Game Boy games. The Smart Boy gained an official license by Samsung for use on their phones. They also released the RetroN 77, an emulation-based Atari 2600 clone that can play most, if not all, of the original game cartridges in 1080p.
In 2019, at E3, Hyperkin announced they will make a console that can play Nintendo 64 cartridges in HD, and output to HDMI. The console is expected to be named the Ultra Retron. The release date is not known. It is not officially known yet whether the console uses an FPGA or emulation, however the unit demonstrated at E3 displayed a lightning bolt icon implying the console uses a Raspberry Pi single-board computer instead of an FPGA. Additionally, the demo unit was displaying graphical artifacts only present in a Nintendo 64 emulator.
References
Video game companies based in California
Computer companies of the United States
Computer hardware companies
Computer peripheral companies
Companies based in Los Angeles | Hyperkin | [
"Technology"
] | 586 | [
"Computer hardware companies",
"Computers"
] |
54,597,635 | https://en.wikipedia.org/wiki/NGC%206940 | NGC 6940 is an open cluster in the constellation Vulpecula. It was discovered by William Herschel in 1784. The cluster is nearly a billion years old and it is located 2,500 light years away. It is considered the finest open cluster in the constellation.
Observation
It is located a bit more than two degrees south-southeast of 41 Cygni and three and a half degrees southwest from 52 Cygni. The cluster is bright enough to be seen even with small binoculars, which can partially resolve it. NGC 6940 is included in the Herschel 400 Catalogue.
Characteristics
NGC 6940 has hundreds of members. The cluster is quite scattered and in between its members are also visible field stars.
For example, two bright stars, an 8.6 mag B8III giant star at the NE edge and a 9.1 mag A0III giant at the SW corner of the cluster are too young to be true members of NGC 6940 and are probably background stars. The brightest star (lucida) of NGC 6940 is the red giant FG Vulpeculae, a semiregular variable star whose magnitude ranges from 9.0 to 9.5 every 80 days approximately. NGC 6940 is rich in red giants, more than 20 according to WEBDA database. Based on the spectroscopic analysis of twelve of them, the cluster age was estimated to be 1.1 billion years, with a turn-off mass of 2 M⊙. Its metallicity is close to the one of the Sun. In NGC 6940 have been detected 8 variable stars whose variability is consistent with the delta Scuti variables.
A study of the cluster by ROSAT in soft X-rays revealed four sources that are identified as cluster members. One more source was attributed to a possible cluster K0 giant star member, which was later confirmed to be a cluster member. Three of these sources were identified as binary stars, from a total of six known to exist in the cluster. The luminosity of the sources was typical of RS Canum Venaticorum variables, close binaries that could retain very active coronal sources despite the age of the cluster.
References
External links
Open clusters
Vulpecula
6940
Astronomical objects discovered in 1784 | NGC 6940 | [
"Astronomy"
] | 452 | [
"Vulpecula",
"Constellations"
] |
54,599,352 | https://en.wikipedia.org/wiki/Lane%20Anderson%20Award | The Lane Anderson Award is an annual award presented to Canadian non-fiction science in two categories; adult and young readers. It is funded by the Fitzhenry Family Foundation, and headed by Sharon Fitzhenry and Hollister Doll. Winners receive a plaque and a prize of 10,000 dollars. Winners are selected based on a book's relevance to current events and on its ability to relate scientific issues to everyday life.
Winners
Young Readers
Adult
References
Canadian non-fiction literary awards
Science writing awards
Awards established in 2011
2011 establishments in Canada | Lane Anderson Award | [
"Technology"
] | 109 | [
"Science and technology awards",
"Science writing awards"
] |
57,874,207 | https://en.wikipedia.org/wiki/NGC%203837 | NGC 3837 is an elliptical galaxy located about 290 million light-years away in the constellation Leo. It was discovered by astronomer William Herschel on April 26, 1785. NGC 3837 is a member of the Leo Cluster.
See also
List of NGC objects (3001–4000)
NGC 3842
References
External links
3837
36476
6701
Leo (constellation)
Leo Cluster
Elliptical galaxies
Astronomical objects discovered in 1785 | NGC 3837 | [
"Astronomy"
] | 85 | [
"Leo (constellation)",
"Constellations"
] |
57,875,269 | https://en.wikipedia.org/wiki/Daniel%20Tordera | Daniel Antonio Tordera Salvador (born 17 January 1986) is a Spanish chemist, material scientist and writer. He is currently an Assistant Professor in the Physical Chemistry Department at the University of Valencia.
Early life and education
Tordera was born in Valencia, where he studied Chemistry at the University of Valencia. He graduated First of his promotion in 2009. He then moved to Strasbourg, where he earned his Material Science Engineers degree at the École européene de chimie, polymères et matériaux. He earned his PhD at the University of Valencia in 2014, working on light-emitting electrochemical cells. He worked as a postdoctoral researcher at the University of Linköping, studying photonics and plasmonic materials. He was then a researcher at Holst Centre (TNO) in Eindhoven working on organic photodetectors, position which he held until October 2020 when he accepted a position as Assistant Professor at the University of Valencia.
Research
Tordera joined University of Valencia in 2009 where he worked in light-emitting electrochemical cells (LECs). He determined the elusive operational mechanism of LECs and dramatically increased the performance of these devices. He was a visiting scientist at University of California, Santa Barbara, where he applied his knowledge on conjugated polyelectrolytes. He then started a company with the aim of commercializing products based on his findings. He joined the University of Linköping to research the optical and thermal properties of plasmonic nanoholes. He worked on the development of a plasmonic thermoelectric device, a photoconductive paper and a plasmonic display, among others. He then joined Holst Centre leading a team working on near-infrarred organic photodetectors. There he created the first large-area thin-film vein detector and contributed to the progress of photodetectors in the fields of biometrics and healthcare. He has published over 50 publications in peer-reviewed scientific journals and is the inventor of 4 patents.
Awards
2020 - Society of Information Display Distinguished Paper.
2015 - Nanomatmol Award: Best PH.D. in Nanotechnology and Molecular Materials in Spain by the Spanish Royal Society of Chemistry.
2015 - Outstanding Doctorate Award by the Universidad de Valencia.
2012 - European Materials Research Society Spring Meeting Young Scientist Award.
2010 - Award “Suschem Young Chemistry Researchers” to the Highest Academic Achievement in Spain by the Spanish Royal Society of Chemistry
Personal life
Daniel Tordera considers himself a politically active person. He has developed a satirical political video game Pedro Sanchez Simulator that was played by more than 50,000 people in less than a month and gained lot of media attention. He enjoys writing, photography and making music.
He received the honor of being one of the 10 finalists to the 2018 Planeta awards for his novel "El Arte de la Fuga"
References
External links
Google Scholar.
1986 births
Living people
Materials scientists and engineers
University of Valencia alumni
Spanish chemists
People from Valencia | Daniel Tordera | [
"Materials_science",
"Engineering"
] | 611 | [
"Materials scientists and engineers",
"Materials science"
] |
57,876,996 | https://en.wikipedia.org/wiki/Binary%20angular%20measurement | Binary angular measurement (BAM) (and the binary angular measurement system, BAMS) is a measure of angles using binary numbers and fixed-point arithmetic, in which a full turn is represented by the value 1. The unit of angular measure used in those methods may be called binary radian (brad) or binary degree.
These representation of angles are often used in numerical control and digital signal processing applications, such as robotics, navigation, computer games, and digital sensors, taking advantage of the implicit modular reduction achieved by truncating binary numbers. It may also be used as the fractional part of a fixed-point number counting the number of full rotations of e.g. a vehicle's wheels or a leadscrew.
Representation
Unsigned fraction of turn
In this system, an angle is represented by an n-bit unsigned binary number in the sequence 0, ..., 2n−1 that is interpreted as a multiple of 1/2n of a full turn; that is, 360/2n degrees or 2π/2n radians. The number can also be interpreted as a fraction of a full turn between 0 (inclusive) and 1 (exclusive) represented in binary fixed-point format with a scaling factor of 1/2n. Multiplying that fraction by 360° or 2π gives the angle in degrees in the range 0 to 360, or in radians, in the range 0 to 2π, respectively.
For example, with n = 8, the binary integers (00000000)2 (fraction 0.00), (01000000)2 (0.25), (10000000)2 (0.50), and (11000000)2 (0.75) represent the angular measures 0°, 90°, 180°, and 270°, respectively.
The main advantage of this system is that the addition or subtraction of the integer numeric values with the n-bit arithmetic used in most computers produces results that are consistent with the geometry of angles. Namely, the integer result of the operation is automatically reduced modulo 2n, matching the fact that angles that differ by an integer number of full turns are equivalent. Thus one does not need to explicitly test or handle the wrap-around, as one must do when using other representations (such as number of degrees or radians in floating-point).
Signed fraction of turn
Alternatively, the same n bits can also be interpreted as a signed integer in the range −2n−1, ..., 2n−1−1 in the two's complement convention. They can also be interpreted as a fraction of a full turn between −0.5 (inclusive) and +0.5 (exclusive) in signed fixed-point format, with the same scaling factor; or a fraction of half-turn between −1.0 (inclusive) and +1.0 (exclusive) with scaling factor 1/2n−1.
Either way, these numbers can then be interpreted as angles between −180° (inclusive) and +180° (exclusive), with −0.25 meaning −90° and +0.25 meaning +90°. The result of adding or subtracting the numerical values will have the same sign as the result of adding or subtracting angles, once reduced to this range. This interpretation eliminates the need to reduce angles to the range when computing trigonometric functions.
Example
In the orbital data broadcast by the Global Positioning System, angles are encoded using binary angular measurement. In particular, each satellite broadcasts an ephemeris containing its six Keplerian orbital elements. Four of these are angles, which are encoded as 32-bit binary angles. In the lower-precision almanac data, 24-bit binary angles are used.
See also
Grade, 1/400 of a full turn
Binary scaling
CORDIC, algorithms for trigonometric functions
Constructible polygon, including all polygons with 2n sides
References
Units of plane angle
Binary arithmetic | Binary angular measurement | [
"Mathematics"
] | 818 | [
"Arithmetic",
"Binary arithmetic"
] |
57,877,415 | https://en.wikipedia.org/wiki/H%26M%20Design%20Award | The H&M Design Award is an design prize for fashion graduates. The prize was established in 2012 to support young designers with starting careers in fashion. The prize is awarded every year by Hennes & Mauritz AB (H&M), a Swedish multinational clothing-retail company. This prize was not awarded in 2021 or 2022.
Recipients
See also
List of fashion awards
References
External links
H&M Design Award Official Website
Fashion awards
Design awards
Awards established in 2012 | H&M Design Award | [
"Engineering"
] | 96 | [
"Design",
"Design awards"
] |
57,877,443 | https://en.wikipedia.org/wiki/StackPath | StackPath was an American edge computing platform provider headquartered in Dallas, Texas. Its founding team was led by Lance Crosby, who also co-founded SoftLayer Technologies, acquired by IBM in 2013.
Acquisitions
MaxCDN (CDN), 2016
Staminus (DDoS mitigation), 2016
Fireblade (WAF), 2016
Cloak (VPN), 2016
Highwinds Network Group (CDN and VPN), 2017
Server Density (Monitoring)
Subsidiaries
MaxCDN
NetDNA, LLC was founded in 2009 as a content delivery network (CDN) with a focus on enterprise customers. The company was founded by David Henzel and Christopher Ueland in Los Angeles.
In 2010, NetDNA partnered with Wowza to launch the HDDN.com brand, a CDN for streaming video.
By 2010, the MaxCDN brand was created as a simpler CDN for both small and large businesses. MaxCDN, LLC operated as a division of NetDNA, LLC.
In 2011, Ben Neumann was CEO of NetDNA. In 2011, NetDNA completed a funding round with Chelsea Management in Los Angeles.
In 2013, NetDNA rebranded the company and its services as MaxCDN, conslidating other services such as HDDN.com under the same name, with the original NetDNA enterprise service rebranded as MaxCDN Enterprise.
MaxCDN was acquired by StackPath in 2016.
Divestitures
In 2019, StackPath sold its VPN lines of business, including IPVanish (acquired as part of the Highwinds Network Group) and Encrypt.me (the new brand of Cloak), to J2 Global.
In August 2023, Stackpath sold its CDN line of business (primarily approximately 100 select enterprise customer contracts as well as other assets) to Akamai following its decision to cease its content delivery network operations. The transaction did not include the acquisition of StackPath personnel or technology.
Investors
StackPath has received funding from investors including Abry Partners, Juniper Networks, and Cox Communications.
Founders
StackPath was founded May 5, 2015, by Lance Crosby, Greg Bock, Steven Canale, Ryan Carter, Paul Drew, Kenji Fukasawa, Jason Gulledge, Andrew Higginbotham, James Leaverton, Andrew Maten, Dawn Mumm, Nick Nelson, and Josh Reese.
References
Content delivery networks
Companies based in Dallas
Internet technology companies of the United States
American companies established in 2015
Internet security
DDoS mitigation companies
Cloud infrastructure
Cloud computing providers | StackPath | [
"Technology"
] | 517 | [
"Cloud infrastructure",
"IT infrastructure"
] |
57,877,600 | https://en.wikipedia.org/wiki/Dshell | Dshell is an open source, Python-based, forensic analysis framework developed by the U.S. Army Research Laboratory, MD. This tool provides users with the ability to develop custom analysis modules which helps them understand events of cyber intrusion. This framework handles stream reassembly of both IPv4 and IPv6 network traffic and also includes geolocation and IP-to-ASN mapping for each connection. Additionally, the framework plug-ins are designed to aid in the understanding of network traffic and present results to the user in a concise, useful manner. Since Dshell is written entirely in Python, the code base can be customized to particular problems by modifying an existing decoder to extract different information from existing protocols.
The U.S. Army Research Laboratory (ARL) released a version of Dshell to GitHub social coding website on December 17, 2014, with more than 100 downloads and 2,000 unique visitors in 18 countries. Before it was publicly released, Dshell had a small, select community of users in several government organizations. Users could use the tool to find the exact information they needed from network data including looking up names, reassembled website requests or decoded malware traffic. ARL chose to release Dshell to GitHub because sharing it with the world created more security teams gaining another specialized tool to keep their networks secure. Furthermore, increasing the security of the Internet as a whole by increasing the number of skilled eyes looking for bugs and potential improvements throughout the code.
In 2014, NASA released more than 1,000 open source projects. Other agencies, such as the National Security Agency, the National Guard and the Air Force Research Laboratory joined shortly after the following year.
GitHub was chosen for Dshell because it allows members to easily download software code, store edits, and provide a mechanism to offer feedback to the original designer. Additionally, rolling enhancements into the official version make it easier to share the software across organizations, bypassing constant emailing or sending CDs. As of June 2016, users have created more than 11,000 copies of the tool and have offered approximately 62 suggested modifications to the original software.
There are additional modules within the Dshell framework that can be accessed to increase network security; however, the ability to rapidly develop and share analytical modules is the core strength of the framework.
References
Computer security software
United States Army equipment | Dshell | [
"Engineering"
] | 484 | [
"Cybersecurity engineering",
"Computer security software"
] |
57,879,180 | https://en.wikipedia.org/wiki/Etiocholanedione | Etiocholanedione, also known as 5β-androstanedione or as etiocholane-3,17-dione, is a naturally occurring etiocholane (5β-androstane) steroid and an endogenous metabolite of androgens like testosterone, dihydrotestosterone, dehydroepiandrosterone (DHEA), and androstenedione. It is the C5 epimer of androstanedione (5α-androstanedione). Although devoid of androgenic activity like other 5β-reduced steroids, etiocholanedione has some biological activity of its own. The compound has been found to possess potent haematopoietic effects in a variety of models. In addition, it has been found to promote weight loss in animals and in a double-blind, placebo-controlled clinical study in humans conducted in 1993. These effects are said to be similar to those of DHEA. Unlike DHEA however, etiocholanedione cannot be metabolized further into steroid hormones like androgens and estrogens.
References
External links
Etiocholanedione (HMDB0003769) - Human Metabolome Database
Experimental anti-obesity drugs
Diketones
Etiocholanes
Steroid hormones | Etiocholanedione | [
"Chemistry",
"Biology"
] | 290 | [
"Biochemistry stubs",
"Biotechnology stubs",
"Biochemistry"
] |
57,879,382 | https://en.wikipedia.org/wiki/Navicula%20de%20Venetiis | A navicula de Venetiis or "little ship of Venice" was an altitude dial used to tell time and which was shaped like a little ship. The cursor (with a plumb line attached) was slid up/down the mast to the correct latitude. The user then sighted the sun through the pair of sighting holes at either end of the "ship's deck". The plumb line then marked what hour of the day it was. Some naviculas had additional information inscribed, such as the latitude of some common English towns, some zodiac signs, etc.
References
Sundials | Navicula de Venetiis | [
"Astronomy"
] | 127 | [
"Astronomy stubs"
] |
57,880,587 | https://en.wikipedia.org/wiki/List%20of%20sequenced%20algae%20genomes | This list of sequenced algal genomes contains algal species known to have publicly available complete genome sequences that have been assembled, annotated and published. Unassembled genomes are not included, nor are organelle-only sequences. For plant genomes see the list of sequenced plant genomes. For plastid sequences, see the list of sequenced plastomes. For all kingdoms, see the list of sequenced genomes.
Dinoflagellates (Alveolata)
See also List of sequenced protist genomes.
Cryptomonad
Glaucophyte
Green algae
Haptophyte
Heterokonts/Stramenopiles
Red algae (Rhodophyte)
Rhizaria
References
Plant | List of sequenced algae genomes | [
"Engineering",
"Biology"
] | 157 | [
"Lists of sequenced genomes",
"DNA sequencing",
"Genetic engineering",
"Genome projects"
] |
57,881,967 | https://en.wikipedia.org/wiki/Trinitrogen | Trinitrogen also known as the azide radical is an unstable molecule composed of three nitrogen atoms. Two arrangements are known: a linear form with double bonds and charge transfer, and a cyclic form. Both forms are highly unstable, though the linear form is the more stable of the two. More-stable derivatives exist, such as when it acts as a ligand, and it may participate in azido nitration, which is a reaction between sodium azide and ammonium cerium nitrate.
The linear form of N3 was discovered in 1956 by B. A. Thrush by photolysis of hydrogen azide. As a linear and symmetric molecule, it has D∞h symmetry, with a nitrogen–nitrogen bond length averaging 1.8115 Å. The first excited electronic state, A2Σu, is 4.56 eV above the ground state.
The cyclic form was identified in 2003 by N. Hansen and A. M. Wodtke using ultraviolet photolysis of chlorine azide. Although the reaction yielded mostly the linear form, about 20% of the molecules were cyclic. The ring has C2v symmetry—an isosceles triangle—in contrast to the linear form that has equal N–N bond-lengths.
References
External links
Homonuclear triatomic molecules
Nitrogen compounds
Allotropes of nitrogen | Trinitrogen | [
"Chemistry"
] | 271 | [
"Allotropes of nitrogen",
"Allotropes"
] |
57,882,429 | https://en.wikipedia.org/wiki/Megaphorb | Megaphorbs are areas with a community of tall, exuberant, perennial herbs. The plant communities provide ground cover and often exist on the margins of wooded areas, terrain that has recently been cleared, or in disturbed areas adjacent to creeks or rivers. These plant communities are often found in mountainous areas.
Areas that a megaphorb layer frequents are margins of wooded areas or forests that have recently been deforested or where logging has occurred. Given the now newly open area it provides ample conditions for a megaphorb layer to produce. Other areas in which megaphorbs may appear are along the banks of streams and rivers where there is a lack of plant life and nothing obstructing the upwards growth of the plants. The root systems provide structure to riverbanks, reducing erosion in seasons of heavy rainfall. Once peak growing conditions are over, the megaphorb layer begins to die off, which provides decaying plant material to the surrounding area. This feeds detritivore species, and eventually boosts the nutrient ratio within the soil.
References
Ecology | Megaphorb | [
"Biology"
] | 221 | [
"Ecology"
] |
57,882,535 | https://en.wikipedia.org/wiki/Tachyspory | Tachyspory is a form of dehiscence where seed is rapidly released from a cone or fruit upon maturity, as opposed to bradyspory, the gradual release of seed over time. It is a word used in botany to describe seed dispersal.
"Tachy" is a word-forming element meaning "rapid, swift, fast", from Latinized comb. form of Greek takhy "swift".
References
Plant physiology | Tachyspory | [
"Biology"
] | 89 | [
"Plant physiology",
"Plants"
] |
57,883,127 | https://en.wikipedia.org/wiki/Organizing%20center | Organizing center may refer to:
Microtubule organizing center
Spemann's Organizer
Certain groups of cells in mesoderm formation, see FGF and mesoderm formation
Primitive streak in Amniotes responsible for gastrulation
a small cell group underneath the stem cells in Arabidopsis and other plants
animal cap cells treated with activin
Pattern formation
Developmental biology | Organizing center | [
"Biology"
] | 76 | [
"Behavior",
"Developmental biology",
"Reproduction"
] |
57,883,846 | https://en.wikipedia.org/wiki/Systainer | Systainers (from sys-tem con-tainers) are modular inter-stacking plastic containers used for transporting power tools. Boxes from different manufacturers are compatible and can be stacked and clipped together. A design using four joining clips was introduced by Festool Tooltechnic in 1993. In 2010 the T-Loc variant was introduced using a rotating handle for connecting and locking of containers, in combination with redesigned feet.
To reduce plastic pollution, Festool designed the Systainer to first allow distribution of products, then be reused in stacking form as reusable packaging for tool transportation and storage.
Several power tool manufacturers use or offer Systainer-compatible variants. Other manufacturers use the alternative Sortimo L-BOXX design.
The term "Systainer" was trademarked in the United States in January 1994.
Dimensions
Variations
In 2009, the design of Tanos' T-Loc stacking boxes was registered in the name of Timo Kuhls.
In 2011, the design of Makita's Makpac stacking boxes was registered in the names of Yuji Yamamoto and Kiyozumi Kokawa.
In 2014, the design of Tanos' cantilever toolbox was registered in the name of Timo Kuhls.
Beginning in 2014, the students at the Heinrich-Hübsch wood-working college in Karlsruhe started making wooden containers for each students' tools. The "Woodbox" design is high, with a transparent area for drill bits in the lid, and a T-Loc closing handle compatible with other systainer cases. In 2016 the teacher of the class, Peter Winklhofer, made the PDF plans available to enable other carpenters and students to build their own versions of the case.
In 2015, the design of Hitachi's micro-sized Hit-Case stacking boxes was registered in the name of Yi-Hung Lin.
In mid-2019, Systainer³ was announced jointly by Festool, Bott, and Tanos. These containers have integrated slide rail slots for direct connection to van racking, and front handles, along with backward compatibility.
Stacking order
References
Further reading
Classic (1992): (expired)
Maxi (1999):
T-Loc (2009):
T-Loc (2009), credit card size (ID-1 format) label holder/attachment interface:
Toolbox (2013):
External links
Woodbox plans from Heinrich-Hübsch college, via BM-Online
Compatibility matrix for Systainer variants
Packaging
Shipping containers
Power tools
Products introduced in 1993
Logistics in Germany
Mechanical_standards | Systainer | [
"Physics",
"Engineering"
] | 531 | [
"Mechanical standards",
"Power tools",
"Physical quantities",
"Power (physics)",
"Mechanical engineering"
] |
57,884,219 | https://en.wikipedia.org/wiki/Machuca%20Massacre | The Machuca massacre () was a massacre that took place in the Colombian village of Machuca, near Segovia, Antioquia on October 18, 1998. Guerillas belonging to the National Liberation Army (ELN) dynamited an oil pipeline, which caused a spreading fire to the village. Seventy people lost their lives, many of them children.
Details
On October 18, 1998, members of the Cimarrones subgroup of the ELN bombed a section of the Ocensa pipeline in Antioquia Department. The blast caused a fireball of crude oil that engulfed the village of Machuca. At first, at least forty were believed to be killed. The death rate eventually hit 70. It was one of the deadliest incidents to civilians in the three decade long Colombian conflict.
Aftermath
The ELN took responsibility for the bombing, but not the deaths. It said that the Colombian army were the ones who ignited the spilled oil. The head of the Colombian armed forces condemned the ELN.
On November 12, Nicolas Rodriguez, head of the ELN, said that the attack was a "grave mistake" and that they would investigate those responsible. State defense chiefs denied the allegations. The bombing hurt the credibility of the ELN, especially as it entered peace negotiations with the government just a week prior to the attack.
The pipeline was operated by British Petroleum (BP). The Guardian reported that BP provided arms equipment to the Colombian army brigade guarding the pipeline, a claim it denied.
See also
List of massacres in Colombia
Notes
1998 murders in Colombia
Massacres of the Colombian conflict
Massacres in 1998
20th-century mass murder in Colombia
October 1998 events in South America
Attacks on buildings and structures in 1998
Improvised explosive device bombings in 1998
Improvised explosive device bombings in Colombia
Industrial fires and explosions
Oil spills in South America
Fires in Colombia
Building and structure arson attacks in South America
Arson in 1998
Attacks on energy sector
Terrorist incidents in Colombia in the 1990s
Terrorist incidents involving incendiary devices
Attacks on buildings and structures in Colombia | Machuca Massacre | [
"Chemistry"
] | 409 | [
"Industrial fires and explosions",
"Explosions"
] |
67,438,557 | https://en.wikipedia.org/wiki/Marin%20Art%20and%20Garden%20Center | The Marin Art and Garden Center is a botanical garden and arts organization in Ross, California. The site is and features gardens and historic buildings, including the Barn Theater, which is home to theater company the Ross Valley Players. Admission to the gardens is free.
The property was added to the National Register of Historic Places on June 6, 2022.
History
The land where the Marin Art and Garden Center sits was part of Rancho Punta de Quentin, a 10,000-acre Mexican land grant purchased by James Ross in 1859. A few years later, the property went to Ross's daughter Annie and her husband George Worn. The acres that make up the current Marin Art and Garden Center were eventually owned by the Jonathan Kittle family, who put the land up for sale in 1943.
The Marin Art and Garden Center was founded in 1945 by women members of the Marin Conservation League. This project was led by the League's president, Caroline Sealy Livermore, who organized fundraising to obtain the $25,000 needed to buy the property. The site was the location for the Marin County Fair from 1947 to 1970.
Gardens and features
The Marin Art and Garden Center's master plan was designed by landscape architect Thomas Church. It contains several different gardens, including those focused on roses, edible plants, plants used in basketry, and native plants. There are three species of redwood on the site, including the dawn redwood. A giant sequoia on the property was brought in from Yosemite Valley during the Worns' ownership.
Buildings on the property include modernist buildings and the Octagon House, which was once a pump house and later the José Moya del Piño Library. There are also an art studio by Gardner Dailey and the "Bottle House" by Ray Oleson, both built in the late 1940s. The property's border is marked by crinkle-crankle brick walls.
Pixie Park Playground, designed by Robert Royston, is located at the center. It was founded in 1952 by Elizabeth Terwilliger and American Association of University Women as a space for MAGC volunteers' children.
Ross Valley Players
The Barn Theater is the headquarters of the Ross Valley Players. The barn was built in 1860 on the farm later owned by the Kittle family. During the Great Depression, the community in Ross began using the barn as a theater. The Ross Valley Players assisted in the effort to turn the land into a garden in 1945.
See also
National Register of Historic Places listings in Marin County, California
Mount Tamalpais Mountain Theater
References
Gardens in California
Botanical gardens in California
Parks in Marin County, California
Octagon houses in California
Bottle houses
National Register of Historic Places in Marin County, California
Barn theatres | Marin Art and Garden Center | [
"Engineering"
] | 550 | [
"Bottle houses",
"Architecture"
] |
67,439,159 | https://en.wikipedia.org/wiki/Plastic%20sequestration | Plastic sequestration is a means of plastic waste management that secures used plastic out of industry and out of the environment into reusable building blocks made by manual compaction. Plastic sequestration is motivated by environmental protection and modeled on the Earth's process of carbon sequestration. Emerging out of the struggle of towns and communities in the Global South to deal with plastic pollution, plastic sequestration compaction methods are characterized by being locally based, non-capital, non-industrial and low-tech. Plastic sequestration is defined by the goals of securing plastic out of the environment and out of high energy/carbon industrial systems. Based on eliminating the chemical and physical and abiotic and biotic degradation pathways, plastic sequestration aims to achieve these goals, by terminally reducing the net surface area of thin film plastics. The building blocks that emerge from plastic sequestration are used in applications that further protect from degradation and permanently keep plastic out of industrial processes, thereby preventing their carbon emissions.
Methodology
Preparation
In general, plastic sequestration begins by segregating plastic from organics and other materials. The plastic is then cleaned and dried before it is manually compacted into dense blocks—typically using a stick or a press.
Examples
Examples of plastic sequestration include ecobricks, cigbricks, ocean ecobricks,ubuntu blox, specifically made dense plastic boards and blocks, and some products of the precious plastic movement. The methods of plastic sequestration is fundamentally distinct from landfilling and plastic burial. The Global Ecobrick Alliance, defines plastic sequestration as a non-industrial, manual, carbon-neutral compaction of used, clean and dry plastic that achieves a density over 0.33g/ml and a specific surface degradation rate (SSDR) below 0.1 μm year−1.
Building Sequestration
Building with the blocks that result from compaction is a part of the process of plastic sequestration. Typically, Cob_(material) / adobe / earth building are used to completely encase the blocks. Earth building applications must protect from all forms of plastic degradation (i.e. heat, light, friction, fire, etc.). Earth building methods ensure that the blocks can be extricated undamaged from the construction when it comes to its end. Earth building methods also ensure that the construction process remains carbon-neutral.
Theory
The concept of plastic sequestration as an ecological service that follows Earth's example of carbon sequestration was laid out at the Le Havre University, 50th Annual Bandung Spirit Conference, in a paper presented by Ani Himawati and Russell Maier. Building on this concept, the Global Ecobrick Alliance developed a theoretical framework and criteria for plastic sequestration in order to exclude applications that are not ecological services, and to encourage sequestration methodologies and applications that are. The criteria of plastic sequestration are based on the principles of Earthen Ethics, that delineate the parameters of ecological contribution, research by Center for International Environmental Law on the carbon impact of the plastic industry, and the science of preventing polymer degradation.
The process secures plastic from all forms of chemical and physical degradation and from industrial processing.
Outputs are indefinitely reusable, while tending towards applications that are of long-term earthen immersion.
The process must be conducted as a not-for-profit, for-Earth enterprise.
The process results in the sequestration of more carbon and more plastic than is added through emissions and replacement plastic.
The process and its outputs support the diversification of life.
The enterprise tracks and publicly discloses all the plastic, carbon and biodiversity impacts of its process.
Science
The goal of plastic sequestration is to create the conditions to prevent the physical and chemical degradation of plastic (i.e. depolymerization, chemical modification, mass loss or mineralization to CO2 and H2O) and the emissions of industrial processing. Plastic polymer degradation occurs in two ways: (i) physical, such as cracking, embrittlement, and flaking, or (ii) chemical, referring to changes at the molecular level. Chemical and physical degradation happens through biotic and abiotic pathways. Plastic sequestration methods must prevent chemical and physical degradation, by blocking biotic (microbial action) and abiotic (light, heat, acids, etc.) degradation pathways and by preventing industrial reprocessing. Emissions occur when plastic is processed industrially (i.e. recycling, landfilling, incineration)
Preventing Chemical and Physical Degradation
Research into the polymer degradation shows that in the environment, degradation occurs on the exposed surface of plastic and that net degradation is directly proportional to the amount of surface area exposed. Mathematical extrapolation indicates that a thin film of HDPE plastic (high surface area) can degrade 1100 times faster than a bead of plastic of the same weight (low surface area). Whereas a thin film of plastic will degrade in 1.8 ± 0.4 years a bead of plastic will endure for 2000 ± 400 years. Furthermore, by reducing the specific surface degradation rate (SSDR) of the low-surface-area plastic, it can endure indefinitely. Thus, plastic sequestration methodologies prioritize the terminal reduction of net surface area of the thin film plastics through compaction and building methods that prevent abiotic and biotic degradation, reducing the SSDR of the plastic to below 0.1 μm year–1.
Preventing Industrial Emissions & Dispersal
On average globally, each metric ton of plastic processed by recycling, land-filing and incineration generates 689kg, 65Kg and 2967kg of CO2e respectively. Research also shows that of all the plastic generated over all-time, the industrial processing of plastic has dispersed 91% of into the biosphere. There it is subject to the chemical and physical degradation pathways mentioned above. Plastic sequestration aims to avoid these emissions and this dispersal by preventing plastic's industrial processing.
Earthen immersion
Research has shown that covering plastic in earth is an effective method of preventing abiotic plastic degradation (i.e. preventing exposure to sunlight, friction, heat, etc.). Even plastic that is designed to degrade, when it is buried in low-oxygen soil, abiotic and biotic are prevented. Research also shows that submerging plastic in inert soil (minimal bacteria, micro-organisms) can further slow plastic degradation.
Earth emulation
Plastic sequestration is modeled on Earth's planetary process of carbon sequestration. Earthen carbon sequestration occurs through the carbon cycle's short and long-term processes: (i) the Earth's process of cycling carbon as life's building blocks (ii) the long-term process of removing carbon out of the atmosphere and sequestering it into geological storage. In the same way, plastic sequestrated blocks have a short and long-term plan: (i) blocks are made to be indefinitely reusable. (ii) blocks are put to use into longer and longer term buildings. Just as the Earth sequestered carbon under ground indefinitely, long-term plastic sequestration applications immerse its blocks in earthen constructions, blocking biotic and abiotic forms of plastic degradation (i.e. photo-degradation, heat, fire and friction).
History
Context
Since 1950 an estimated 8,300 million metric tons (Mt) of virgin plastics have been produced worldwide; 9% of which has been recycled, 12% were incinerated and 79% have accumulated in landfills or the natural environment.
In the early 2000s, the increase in plastic products and packaging became an overwhelming problem for rural towns and communities. Without recourse to industrial [plastic recycling], incineration or waste exportation, plastic waste began to become a serious aesthetic and environmental issue for towns and villages in the global south.
Global South emergence
Driven by local aesthetic and environmental concerns, plastic solution innovation has been led by communities in the global south. In particular, grass roots methods practically and physically dealing with plastic pollution first emerged in the global south. Examples include Ecobrick movement, Ubuntu Blox, and the Precious Plastic brick creation.
These methods of plastic compaction were characterized by being locally based, non-capital, and non-industrial. The original focus of these methods was to turn large amounts of waste plastic into valuable, saleable products (i.e. bricks, boards, blocks, etc.) that could be "sustainable substitute for equivalents" to traditional construction materials.
Shift to sequestration
Over the last decade, research on plastic loose in the environment has demonstrated clearly the deleterious effects on human health and ecological effects. leading to a steady increase in the awareness of the effects of dumped, recycled and burned plastic. As awareness increased, the focus of grassroots upcycling shifted from creating products of value to a focus on securing plastic from contaminating the biosphere and being industrially processed, leading to the concept of 'plastic sequestration' being coined. Plastic sequestration emerged to focus on the value of 'the absence of plastic from the biosphere' and the value of avoiding the carbon impact of industrial processing.
Global North emergence
On January 1, 2018, China banned plastic imports in its National Sword program. Displaced plastic exports from Europe and America were diverted to Indonesia, Turkey, India, Malaysia, and Vietnam where lacking environmental regulations have resulted in wholesale air, water and earth pollution around processing plants. Through popular documentaries and investigative journalism, public skepticism of industrial and government recycling programs began to increase. 2018 Consequently, a movement in western countries turned to methods such as ecobricking and home-made plastic recycling machines, to manage plastic instead.
References
Pollution control technologies | Plastic sequestration | [
"Chemistry",
"Engineering"
] | 2,004 | [
"Pollution control technologies",
"Environmental engineering"
] |
67,439,252 | https://en.wikipedia.org/wiki/Lam%27s%20problem | In finite geometry, Lam's problem is the problem of determining if a finite projective plane of order ten exists.
The order ten case is the first theoretically uncertain case, as all smaller orders can be resolved by purely theoretical means.
Lam's problem is named after Clement W. H. Lam who experimentally determined that projective planes of order ten do not exist via exhaustive computational searches.
Introduction
A finite projective plane of order is a collection of points and lines such that
any two points define a unique line,
any two lines meet at a unique point,
there are exactly points on every line, and
there are exactly lines through every point.
A consequence of this definition is that a projective plane of order will contain points and lines.
The incidence relation between points and lines may equivalently be described using an incidence matrix. In this context a projective plane of order
is equivalent to a matrix with entries such that every row and column has ones
and the inner product between any two rows or columns is exactly .
Using the incidence matrix representation, Lam's problem is equivalent to determining if there is a way of placing 0s and 1s in a matrix such that there are exactly eleven 1s in each row and column and any pair of
rows share a single 1 in the same column.
Lam considered studying the existence of a projective plane of order ten in his PhD thesis but was dissuaded by his thesis advisor H. J. Ryser who believed the problem was too difficult.
Resolution
Edward Assmus presented a connection between projective planes and coding theory at the conference Combinatorial Aspects of Finite Geometries in 1970.
He studied the code generated by the rows of the incidence matrix of a hypothetical projective plane of order ten and derived a number of restrictive properties that such a code must satisfy.
In particular, the enumerator polynomial of the code is completely determined by the number of words of weights 12, 15, and 16 in the code.
Over the next two decades a number of computer searches showed that the hypothetical code associated with the projective plane of order ten does not contain words of weights 15, 12, and 16—which implied that it must contain words of weight 19.
Finally, Clement Lam, Larry Thiel and Stanley Swiercz used about three months of time on a Cray-1A supercomputer to show that words of weight 19 are also not present in the code.
This resolved Lam's problem in the negative.
Their result was independently verified in 2021 by using a SAT solver to generate computer-verifiable certificates for the correctness of the exhaustive searches.
References
Finite geometry
Combinatorial design | Lam's problem | [
"Mathematics"
] | 530 | [
"Combinatorial design",
"Combinatorics"
] |
67,439,420 | https://en.wikipedia.org/wiki/One%20Through%20Zero%20%28The%20Ten%20Numbers%29 | One Through Zero (The Ten Numbers) is a monumental series of sculptures by the American artist Robert Indiana. The work depicts the numerical digits 1, 2, 3, 4, 5, 6, 7, 8, and 9 and 0. The work was created between 1980 and 2001. The numbers are made from polychrome aluminium with each measuring 72 x 72 x 36 in. (182.9 x 182.9 x 91.4 cm.).
The use of numbers became prominent in Indiana's artworks from the end of the 1950s and became an established part of his style in the 1960s. The design of the numbers was inspired by a printer's calendar Indiana found in his loft in Coenties Slip. The piece was first created for a property developer in Indianapolis; the work was then donated to the Indianapolis Museum of Art. The work was subsequently created for a siting in Park Avenue in New York City in 2003 as part of the 'Art on the Park' series, outside Beverly Hills City Hall in 2005, and on Lime Street, London from 2013 as part of the City of London's 'Sculpture in the City' series. An edition of One Through Zero (The Ten Numbers) made from COR-TEN steel was displayed in London's Regent's Park in 2019.
Indiana had previously created a work with the poet Robert Creeley of a book of poems with poems about each number facing Indiana's screen printed coloured numbers.
Interpretation and meaning
The digits can be arranged in any order to generate new meanings and interpretations.
Indiana ascribed particular meanings to the colours that he chose for each digit.
Indiana's website ascribes the meanings as:
One: Red and blue, associated with birth
Two: Green and blue, signifying infancy
Three: Orange and blue representing youth
Four: Yellow and red, connected to adolescence
Five: White and blue signifying the 'pre-prime' of life
Six: Green and red signifying the prime of life
Seven: Blue and orange suggesting the 'early autumn' of life
Eight: Purple and red signalling autumn
Nine: Black and yellow conveying a sense of warning
Ten: The use of grey signals the end of the biological life cycle
References
1980 sculptures
Sculptures by American artists
Numbers | One Through Zero (The Ten Numbers) | [
"Mathematics"
] | 452 | [
"Arithmetic",
"Mathematical objects",
"Numbers"
] |
67,442,125 | https://en.wikipedia.org/wiki/Yiddish%20symbols | A number of Yiddish symbols have emerged to represent the language and the Yiddishist movement over history. Lacking a central authority, however, they have not had the prominence of those of the Hebrew revival and the Zionist symbols of Israel. Several of the Yiddish symbols are drawn from Yiddish songs in the klezmer tradition.
Yiddish symbols
The Golden Peacock
The Golden Peacock (Yiddish: די גאלדענע פאווע) has historically been a common symbol in Yiddish literature, popularized by "Di Goldene Pave". It has often been a subject of Yiddish poetry, including a collection under that title from Moyshe-Leyb Halpern. Yiddishpiel uses a logo of golden peacock plumage surrounding its theatre building, while The Forward has used gold in its masthead (also recalling Di Goldene Medine) since 2015, A variation of this symbol has been used as the logo of the Yiddish cafe Pink Peacock in Glascow, Scottland.
The Golden Goat
The traditional Jewish lullaby "Raisins and Almonds" popularized the golden goat as a Yiddish symbol, echoing that in Chad Gadya, a traditional Passover song. The Yiddish Book Center has adopted the golden goat as its logo since 2012, designed by Alexander Isley with lettering from El Lissitzky's lithographs of Chad Gadya.
Komets-Alef
In the modern era, some have turned to the komets-alef in search of a symbol for the Yiddish language, a letter that "Oyfn Pripetshik" highlights as a distinctive letter in Yiddish orthography in a play on a Yiddish alphabet song. This particular letter () is also used to represent Yiddish on Duolingo, replacing a "Yiddish flag" on the pattern of the flag of Israel but in black with a menorah, promoted by a user from Wikimedia Commons which was used for a time in the Duolingo Incubator.
Flags
There is no historical language or ethnic flag for Yiddish speakers, though in the 21st century there have been some minor proposals for digital use as flag icons for languages.
Flag with a menorah
It appeared on the internet around 2012, when it was published on Wikipedia. Rapidly, it disseminated in the internet, becoming number one result in any google search for “Yiddish flag”. Soon after, Duolingo, a vocabulary learning app, started using it for promoting its Yiddish course. Following the publication of the article "What Flag Should Yiddish Fly?", which criticized the flag for its gloomy appearance and resemblance to the flag of Israel (which was considered inappropriate due to an unfavorable policy towards Yiddish in Israel's early years), Duolingo changed it to the komets alef. Claims that the flag originated in anarchist milieu in the early 20th century are not true.
See also
Yiddishkeit
Yiddishist movement
References
Jewish symbols
Lists of symbols
Yiddish
Language identifiers | Yiddish symbols | [
"Mathematics"
] | 607 | [
"Symbols",
"Lists of symbols"
] |
67,444,140 | https://en.wikipedia.org/wiki/Dactyliosolen | Dactyliosolen is a genus of diatoms belonging to the family Rhizosoleniaceae.
Species:
Dactyliosolen alternans
Dactyliosolen antarcticus
Dactyliosolen areolatus
References
Diatoms
Diatom genera | Dactyliosolen | [
"Biology"
] | 61 | [
"Diatoms",
"Algae"
] |
67,444,163 | https://en.wikipedia.org/wiki/Rhizosoleniaceae | Rhizosoleniaceae is a family of diatoms belonging to the order Rhizosoleniales.
Genera:
Calyptrella Castillo, 1996
Dactyliosolen A.F.Castracane, 1886
Guinardia H.Peragallo, 1892
Henseniella F.Schütt ex G.B.De Toni, 1894
Neocalyprella Hernàndez-Becerril
Neocalyptrella Castillo, 1997
Proboscia B.G.Sundstrom, 1986
Pseudosolenia B.G.Sundstrom, 1986
Rhizosolenia T.Brightwell, 1858
Urosolenia F.E.Round & R.M.Crawford, 1990
References
Diatoms
Diatom families | Rhizosoleniaceae | [
"Biology"
] | 154 | [
"Diatoms",
"Algae"
] |
67,444,568 | https://en.wikipedia.org/wiki/Diatoma | Diatoma is a genus of diatoms belonging to the family Fragilariaceae.
The genus has cosmopolitan distribution.
Species:
Diatoma angusticostata
Diatoma arcuatum
Diatoma auritum
Diatoma elongata
References
Diatoms
Diatom genera | Diatoma | [
"Biology"
] | 61 | [
"Diatoms",
"Algae"
] |
67,444,847 | https://en.wikipedia.org/wiki/Rhodium%28IV%29%20fluoride | Rhodium(IV) fluoride is a chemical compound of rhodium and fluorine. It is formed when rhodium(III) bromide reacts with bromine trifluoride. Iridium(IV) fluoride, palladium(IV) fluoride and platinum(IV) fluoride have the same crystal structure.
References
Rhodium compounds
Fluorides
Platinum group halides | Rhodium(IV) fluoride | [
"Chemistry"
] | 89 | [
"Fluorides",
"Salts"
] |
67,446,631 | https://en.wikipedia.org/wiki/Dot%20planimeter | A dot planimeter is a device used in planimetrics for estimating the area of a shape, consisting of a transparent sheet containing a square grid of dots. To estimate the area of a shape, the sheet is overlaid on the shape and the dots within the shape are counted. The estimate of area is the number of dots counted multiplied by the area of a single grid square. In some variations, dots that land on or near the boundary of the shape are counted as half of a unit. The dots may also be grouped into larger square groups by lines drawn onto the transparency, allowing groups that are entirely within the shape to be added to the count rather than requiring their dots to be counted one by one.
The estimation of area by means of a dot grid has also been called the dot grid method or (particularly when the alignment of the grid with the shape is random) systematic sampling. Perhaps because of its simplicity, it has been repeatedly reinvented.
Application
In forestry, cartography, and geography, the dot planimeter has been applied to maps to estimate the area of parcels of land. In botany and horticulture, it has been applied directly to sampled leaves to estimate the average leaf area.
In medicine, it has been applied to Lashley diagrams as an estimate of the size of brain lesions.
In mineralogy, a similar technique of counting dots in a grid is applied to cross-sections of rock samples for a different purpose, estimating the relative proportions of different constituent minerals.
Theory
Greater accuracy can be achieved by using a dot planimeter with a finer grid of dots. Alternatively, repeatedly placing a dot planimeter with different irrational offsets from its previous placement, and averaging the resulting measurements, can lead to a set of sampled measurements whose average tends towards the true area of the measured shape. The method using a finer grid tends to have better statistical efficiency than repeated measurement with random placements.
According to Pick's theorem, published by Georg Alexander Pick in 1899, the version of the dot planimeter with boundary dots counting as 1/2 (and with an added correction term of −1) gives exact results for polygons that have the dots as their vertices. According to Blichfeldt's theorem, published by Hans Frederick Blichfeldt in 1914, it is always possible to shift a dot planimeter relative to a given shape without rotating it so that the number of dots within the shape is at least equal to its area.
The Gauss circle problem concerns the error that would be obtained by using a dot planimeter to estimate the area of a circle. As its name suggests, it was studied in the early 19th century by Carl Friedrich Gauss. The maximum error is known to be bounded by a fractional power of the radius of the circle, with exponent between 1/2 and 131/208.
Related devices
The dot planimeter differs from other types of planimeter, which measure the area of a shape by passing a device around its boundary.
The Steinhaus longimeter is a similar transparency-based device for estimating the length of curves by counting crossings.
References
External links
Dot planimeter, Chris Staecker, Fairfield University
Area
Dimensional instruments
Lattice points
Mathematical tools
Measuring instruments | Dot planimeter | [
"Physics",
"Mathematics",
"Technology",
"Engineering"
] | 651 | [
"Scalar physical quantities",
"Physical quantities",
"Dimensional instruments",
"Applied mathematics",
"Quantity",
"Lattice points",
"Measuring instruments",
"Size",
"Number theory",
"Mathematical tools",
"History of computing",
"nan",
"Wikipedia categories named after physical quantities",
... |
67,447,218 | https://en.wikipedia.org/wiki/Huff%20model | In spatial analysis, the Huff model is a widely used tool for predicting the probability of a consumer visiting a site, as a function of the distance of the site, its attractiveness, and the relative attractiveness of alternatives. It was formulated by David Huff in 1963. It is used in marketing, economics, retail research and urban planning, and is implemented in several commercially available GIS systems.
Its relative ease of use and applicability to a wide range of problems contribute to its enduring appeal.
The formula is given as:
where :
is a measure of the attractiveness of store j
is the distance from the consumer's location, i, to store j.
is an attractiveness parameter
is a distance decay parameter
is the total number of stores, including store j
References
Retail analytics
Economics models
Spatial analysis | Huff model | [
"Physics"
] | 163 | [
"Spacetime",
"Space",
"Spatial analysis"
] |
67,447,407 | https://en.wikipedia.org/wiki/Sherpa%20%28fabric%29 | Sherpa is a fabric with a pile on one side and flat on the other side.
Structure
Sherpa is a curly piled fabric structure made of synthetic yarns like acrylic or polyester. The texture is soft and fluffy, useful in jackets resembling wool or sheepskin on the piled side. Sherpa fleece is a knitted type of fabric usable in line clothing and winter wear.
History
It was Collins & Aikman (An American manufacturer of decorative fabrics and automotive supplies) who first developed this fabric. Sherpa was the registered trademark of the company.
Use
Mainly it is used in the lining of coats and for adult's and children's jackets.
See also
Polar fleece
References
Textiles | Sherpa (fabric) | [
"Physics"
] | 148 | [
"Materials stubs",
"Materials",
"Matter"
] |
67,448,402 | https://en.wikipedia.org/wiki/Sanitary%20movement | The sanitary movement of urban planning began in the United Kingdom in 1838, with the Central Poor Law Commission's findings on the "physical causes of fever in the Metropolis which might be prevented by proper sanitary measures". Basing its sanitation beliefs on miasma theory (as opposed to germ theory), its agenda was based on the construction of sewage systems, street-paving, and the provision of clean water. The movement spread to the United States in the 1840s, reaching its peak in 1880 before declining in the 1890s. Edwin Chadwick played a major part in inspiring the movement.
While the sanitary movement never theorized about the model city or urban design, as it was only interested in cities due to their environmental importance for disease, the movement did nevertheless spur a 'townsite consciousness' about certain general principles that cities should follow. These included an open and green setting without crowding or congestion, with access to clean air, water, and exercise opportunities, as well as not having dark and unventilated buildings or polluting industries in built-up areas.
See also
History of urban planning
Sanitation
History of water supply and sanitation
History of public health
References
Urban planning | Sanitary movement | [
"Engineering"
] | 236 | [
"Urban planning",
"Architecture"
] |
67,450,278 | https://en.wikipedia.org/wiki/2021%20Sv%C4%9Btec%20train%20crash | The 2021 Světec train crash was a collision of two freight trains, which occurred at Světec railway station in Světec, Czech Republic on 4 April 2021 at 14:16 CEST. An express freight train (), no. 54334, operated by ORLEN Unipetrol Doprava (UNIDO) and hauled by a CZ Class 753.7, collided with a continuous freight train (), no. 66403, operated by ČD Cargo (ČDC) and hauled by a CZ Class 123. The driver of the UNIDO train, which was carrying tank cars filled with propane and butane, died upon impact. The driver of the ČD Cargo train, which was carrying coal, saved himself by jumping out of the locomotive. A fire broke out on one of the locomotives, and 9 firefighter units and an air ambulance responded to the accident. According to preliminary information, the railway signalling had worked correctly, so the accident was probably caused by the UNIDO train driver killed in the crash.
The total damage was calculated at about 50 million CZK (34 mil. CZK to the UNIDO train, 9 mil. CZK to the ČDC train, 4.5 mil. CZK to the infrastructure).
References
Světec train crash
Accidents and incidents involving České dráhy
Svetec train crash
Derailments in the Czech Republic
Svetec train crash
Ústí nad Labem Region
Train collisions in the Czech Republic | 2021 Světec train crash | [
"Technology"
] | 307 | [
"Railway accidents and incidents",
"Rail accident stubs"
] |
67,451,331 | https://en.wikipedia.org/wiki/Muellerella%20ventosicola | Muellerella ventosicola is a species of lichenicolous fungus in the family Verrucariaceae. It shows preference to growing on species of the genus Rhizocarpon but can also associate with other genera.
Muellerella ventosicola has been reported growing on Rhizocarpon geographicum in Iceland, Sicily and in Ukraine, on Rhizocarpon grande in Ukraine and an unknown Rhizocarpon species in the Tatra Mountains of Poland. It has also been reported on the genera Ophioparma and Protoparmelia.
References
Verrucariales
Fungi described in 2003
Fungi of Iceland
Fungi of Europe
Fungus species
Lichenicolous fungi | Muellerella ventosicola | [
"Biology"
] | 140 | [
"Fungi",
"Fungus species"
] |
67,451,399 | https://en.wikipedia.org/wiki/Organization%20for%20Ethical%20Source | The Organization for Ethical Source (OES) is a non-profit organization founded by Coraline Ada Ehmke in December 2020, to support the ethical source movement, which promotes that "software freedom must always be in service of human freedom". The organization is dedicated to "giving technologists tools and resources to ensure that their work is being used for social good and to minimize harm". It develops tools to "promote fair, ethical, and pro-social outcomes for those who contribute to, or are affected by, open source technologies".
The organization aims to support the ethical source movement, promoting ethics and social responsibility in open source. The movement has facilitated a new kind of license, the Hippocratic License, inspired by the medical Hippocratic Oath. The license has been criticized as non-enforceable and non-open source, including by Bruce Perens, co-founder of the Open Source Initiative and author of the Open Source Definition. The license has triggered debate within the open source movement. The Hippocratic License has been classified as non-free by the Free Software Foundation, while the Open Source Initiative stated, on Twitter, that the license is not an open source software license and that software distributed under such license is not open source.
During the 2021 controversy around Richard Stallman returning to the FSF board, after his resignation in 2019, the OES issued a statement against it, and was one of the signatory organizations of an open letter with thousands of signatures.
See also
Contributor Covenant
Inclusive language
Open source movement
Women in Computing
References
External links
Free and open-source software organizations
Organizations established in 2020
Non-profit technology
Intellectual property activism
Digital rights organizations
Charities based in Switzerland | Organization for Ethical Source | [
"Technology"
] | 342 | [
"Information technology",
"Non-profit technology"
] |
67,452,168 | https://en.wikipedia.org/wiki/Food-entrainable%20oscillator | The food-entrainable oscillator (FEO) is a circadian clock that can be entrained by varying the time of food presentation. It was discovered when a rhythm was found in rat activity. This was called food anticipatory activity (FAA), and this is when the wheel-running activity of mice decreases after feeding, and then rapidly increases in the hours leading up to feeding. FAA appears to be present in non-mammals (pigeons/fish), but research heavily focuses on its presence in mammals. This rhythmic activity does not require the suprachiasmatic nucleus (SCN), the central circadian oscillator in mammals, implying the existence of an oscillator, the FEO, outside of the SCN, but the mechanism and location of the FEO is not yet known. There is ongoing research to investigate if the FEO is the only non-light entrainable oscillator in the body.
Discovery
In 1922, the study of food anticipatory activity (FAA) began with scientist Curt Richter after he observed a rhythm in the wheel activity of rats in relation to constant feeding times. In his experiment, Richter would feed rats held in constant environmental conditions at noon daily for twenty-five minutes. The wheel activity of the rats was recorded to decrease immediately after feeding, then rapidly increase within 2 to 3 hours before feeding again. This daily 24-hour pattern persisted and was discovered to depend upon the time of food presentation. Richter attributed this behavior to the "clock-like functioning" of the stomach.
The occurrence of anticipatory behavior was confirmed in additional research regarding the effects of daily feeding schedules on both rat and mice behavior. For example, Bolles and deLorge found that rats exposed to a 24-hour light-dark (LD) cycle displayed anticipatory wheel-running activity when maintained under a 24-hour feeding schedule. This same anticipatory rhythm, however, was not maintained under 19 and 29-hour feeding schedules, suggesting that FAA was controlled either by the external 24-hour light cues or by a 24-hour circadian clock. Although, it was soon discovered that rats' activity followed externally imposed light schedules for up to 28-hours, but was lost at 29-hours. Thus, light cues were found to be neither a necessary nor sufficient input to produce anticipatory behavior.
Further research of FAA in the 1970s documented that an autonomous circadian oscillator outside the suprachiasmatic nucleus (SCN) must control the food anticipatory activity. The SCN is a region in the brain known to control circadian rhythms in mammals which can be influenced by external light cues. Researcher Friedrich Stephan established that SCN-lesioned rats maintained in constant light (LL) show anticipatory lever-pressing behavior with feeding schedules under 23 and 25-hours, but not 18 or 30-hour schedules. Anticipatory wheel-running was also observed with feeding schedules under 23-hours, but not with 18-hour schedules. Stephan attributed these results to a circadian oscillator, named the food-entrainable oscillator (FEO), that controls the output of anticipatory behavior. The FEO was determined to be autonomous and circadian because its 24-hour rhythm persisted in constant conditions and could also be entrained to a range of feeding intervals. Results suggested that anticipatory wheel running activity developed within 2–4 days of the experiment and as quickly in rats with SCN lesions than as in the controls. Furthermore, restricted feeding schedules were found to be capable of entraining these circadian oscillators and enabling rats to anticipate a 24-hour feeding schedule. This was an important discovery in the field of circadian biology, as it highlighted the potential existence of other circadian oscillators outside the SCN, which was believed to be the master circadian clock in mammals.
Results in experiments with SCN-lesioned mice demonstrated that lesions of the SCN abolish free-running and light-dark (LD) entrained behavioral rhythms, but do not interfere with the development of anticipatory wheel-running or lever-pressing behavior. Thus, the FEO must be located outside of the SCN. Other experiments have also concluded that the FEO does not exist in dozens of other brain regions, although the anatomical location of the FEO remains an unsolved circadian mystery.
Mechanism
The components of a circadian clock are the input, pacemaker, and output. The input of the self-sustaining oscillator, FEO, is food and the output is food anticipatory activity (FAA). This activity is correlated with an increase in an organism's activity leading up to feeding time. The FAA is present in constant conditions such as fasting/time-restricted feeding, and it synchronizes to food that is presented in time intervals that follow a circadian (24 hour) rhythm. Time-restricted feeding is when all of the caloric intake for a day is limited to certain times of the day. A frequent circadian timekeeping mechanism involves CLOCK/BMAL genes, cryptochrome/period genes, and a transcription/translation feedback loop (TTFL) operating in the suprachiasmatic nucleus (SCN). Clock genes are transcribed and translated into a protein product, and this protein accumulates and inhibits the promoter of the clock genes from initiating transcription. However, CLOCK mutant, cryptochrome (Cry) knockout, period (Per) knockout, and SCN knockout mice all had FAA present, so the FEO appears to not operate through the traditional circadian timekeeping mechanism.
Circadian genes
Studies have shown that Per1, Per2, and Per3 knockout mice continue to have robust FAA; these genes are not necessary for FEO oscillatory activity. Research into Bmal1 knockout mice has been more mixed, but many studies have concluded that FAA can be achieved without the Bmal1 gene. Cry1, Cry2, and NPAS2 (Clock gene paralog) knockout mice also show FAA activity, so none of these are necessary for the FEO. Still, these circadian genes have a modulatory effect on FEO activity. Mice that have their Per1/Per2/Per3 genes knocked out have FEO rhythms with shortened periods, and the same is true for Cry1 knockout mice. Cry2 knockout mice have longer periods for their FEO rhythms. Thus, the Per and Cry genes are involved but not necessary for FEO timekeeping. NPAS2 knockout mice show delayed expression of FAA, so it affects the input/output of FAA or the FEO timekeeping itself. The studies that looked at these knockout mice were conducted by Pitts et al., Iijima et al., and Pendergast et al. Yet, clock gene expression drastically increases in the dorsomedial hypothalamic nuclei (DMH) during restricted feeding, and this expression continues without feeding, indicating the circadian oscillatory activity of the FEO. Thus, it is likely that traditional clock genes are heavily involved or necessary for the FEO. This is still not resolved.
Neurotransmitter signaling
Out of the researched neurotransmitters, only disrupting the dopamine signaling pathway appears to disrupt normal FAA. It is postulated that the FEO may be in the dopaminergic circuitry. Mice without a functional Dopamine D1 receptor have attenuated FAA. Mice that are given a D1 receptor agonist show FAA without restricted feeding (a condition required for it otherwise). Thus, the dopamine pathway regulates the FAA, but it is unclear if it impacts the input, pacemaker, or output portion of the FEO pathway.
Hormone and neuropeptide signaling
Hormones involved with the regulation of food intake have been investigated for their role in the FEO timekeeping mechanism. Leptin, a hormone that suppresses food intake, is not required for FAA, but it influences the extent of FAA. Ghrelin, a hormone that increases in the plasma leading up to mealtime and activates the dopaminergic pathway, also has a modulatory effect on FAA but is not necessary for it. The signaling pathways of leptin and ghrelin lead to the hypothalamus’ melanocortin system, and research into this system has also shown that it modulates, but is not necessary for, FAA.
The neuropeptides, Orexin A and B, stimulate food intake, and they have a modulatory effect on FAA but are not necessary for it. Neuropeptide Y also stimulates food intake and increases expression prior to restricted feeding, but it has not been found to affect FAA. Proteins involved in the SCN pathway (Prokineticin 2 (PK2), vasoactive intestinal peptide (VIP), pituitary adenylate cyclase-activating peptide (PACAP)) do not influence the FAA. Sirtuin 1(Sirt1) regulates physiological responses to food intake, and appears to modulate, but not be necessary for FAA. RGS16, a gene regulating G-protein coupled receptor signaling, attenuates FAA but is also not necessary for it.
Location in mammals
Search for FEO
Up until the 1990s it was believed that the SCN controlled all aspects of timekeeping. However, it is well accepted that peripheral tissues including the liver and the gut also contain molecular machinery. These peripheral oscillators receive phase-resetting information from SCN but also respond to other entraining factors such as fasting/feeding being the most important. The SCN can inhibit or activate hypothalamic behavior that stimulates behavior, neuroendocrine stimulation for hormone secretion, and pre-autonomic hypothalamic neurons that affect parasympathetic and sympathetic autonomic centers in the brain stem and spinal cord (dorsal motor nucleus of the vagus), intermediolateral column of the spine). Both neuronal signaling and peripheral tissues such as the gut and liver are believed to send metabolic information to the hypothalamus via the nucleus of the solitary tract (NTS) and the parabrachial nucleus. These peripheral clocks and SCN provide information to hypothalamus about energy homeostasis. Although precise location is not identified, it appears that these oscillators are mainly entrained by feeding and fasting signals, alterations in timing, amount/composition of food, and disruption of normal clock.
Hypothalamic
Identification for possible anatomical location(s) of the FEO remains unsolved. However, recent work highlights where the FEO may not be located, leading to alternative possibilities that the FEO may not be in a distinct anatomical location. Work by Gooley et al. suggests that the dorsomedial hypothalamic nuclei (DMH) may be involved in the generation of the food anticipatory activity (FAA). Upon inducing cell-specific lesions to the DMH, the FAA in rats are diminished and is further supported by measuring EEG in these rodents. However, these reports have been challenged by Landry et al. that show that DMH-lesioned rats still portray behavior of meal anticipation even during periods of complete food deprivation.
Nutrient sensor
Nutrient sensors of the mammalian species, in particular AMP-activated protein kinase (AMPK). AMPK has been suggested as a potential source of peripheral oscillator being that it is a critical nutrient sensor that is found in every tissue of the body. In the hypothalamus, AMPK measures balance of available energy (ATP). Activated AMPK responds to increased food intake and increased expression of orexigenic neuropeptides NPY and agouti-related protein (AgRP) in the arcuate nucleus of the hypothalamus. It has been proposed that AMPK is an internal oscillator of nutrients as opposed to light in the thought that light could not penetrate all cells of mammalian tissues. AMPK also contributes to circadian phosphorylation of CRY1, reducing association of Per2. The presence or absence of glucose and fatty acids, loss of AMPK in the mouse liver has led to disrupted circadian rhythms in hepatic clock genes, pointing to the idea that AMPK has very tight connections in how nutrient regulation in peripheral tissues can have a role in specifically altering the circadian clock.
Another nutrient sensor in cAMP-response element (CRE) binding protein (CREB) also play a role and may be involved as part of FEO location. It has been suggested that the CREB in peripheral tissues such as the liver is involved in circadian phosphorylation and appetite regulation. Specifically, the phosphorylation of CREB is increased during periods of fasting and decreased during periods of feeding. In both rat and hamster models, light stimulus at night has been found to increase CREB phosphorylation and this has led to increased c-fos transcription as well as increase Per transcription in the SCN that is believed to be involved in entrainment. It is believed that feeding-induced alterations of a possible FEO site such as the CREB only take place in peripheral tissues, suggestive that this may be a mechanism in which food-induced alterations can influence desynchronization between central and peripheral clocks.
Gut
Gut signaling in mammals may be key in understanding the entrainment of feeding/fasting in both rodents and humans-particularly the gut microbiome, bile acids, incretins, nutrients, and metabolites. An example of this is the liver's response when food is accessible with noted ~5000 active liver transcripts upregulated in anticipation of food in rodents compared to ~350 transcripts during food restriction. These anticipatory food mechanisms point to an interconnectedness of peripheral oscillators such as the liver and gut microbiota. It has been shown that animals and humans that experience “shift work” outside of their normal fasting/feeding cycles demonstrate disruption in feeding cycles as noted by alterations of circadian genes. Supporting this, human observational work has noted lower energy expenditure at night and single nucleotide polymorphisms (SNPs) in the CLOCK gene with noted susceptibility to increased risk of metabolic syndrome. With this in mind, the gut is such a peripheral target for the FEO due to its connection to the brain and ingested foods. Candidate targets in the gut for entrainment could be the gut lumen that shares such intimate contact with foods, distinctly the enteroendocrine cells (EECs). The identification of EECs as a possible source of FEO is that they contain many nutrient sensing and dependent receptors that can trigger section of gut peptides including incretins, peptide YY, cholecystokinin, gastrin, serotonin, and secretin.
Non-mammals
In pigeons
In pigeons, there is evidence of a FEO that functions separately from photic-entrainable oscillators. The experimental design to confirm the presence of FEO in rats was to lesion their SCNs, but because it is impossible to lesion the SCNs of pigeons, to prove FEO presence the pigeons were kept in 12 hr light and 12 hr dark light cycle and fed at a fixed time every day. In anticipation of feeding, the core body temperature of the pigeons rose. When the pigeons were not given their daily meal, their normal anticipatory behavior persisted. It was only with ad lib feeding that caused the birds to free run, which confirms the presence of a separate, food-entrainable oscillator.
In goldfish
An experimental study designed to determine if food entrainable oscillator activity occurs in goldfish Carassius auratus found that goldfish demonstrated FAA and that scheduled feedings were able to entrain locomotor activity rhythms in goldfish. When given a single meal once a day in the middle of the day, the fish developed anticipation of the food, and this anticipation continued even once the fish were moved from LD conditions to constant conditions of DD. Additionally, when the feeding cycle was shifted by 9 hrs in DD, the fish were able to resynchronize their activity rhythms to feeding times. The continuation of the fish's synchronization and adaptation to new feeding times in DD proves that feeding, not light was causing the rhythms in anticipatory activity.
However, more research is needed to definitively prove the presence of an FEO in fish. It is evident that in DD the food is acting as the only thing that can entrain the fish, but it is possible that in LD an FEO and light-entrainable oscillator (LEO) work together and are coupled to cause anticipatory rhythms. It is also possible that another mechanism allows fish to anticipate food times, so the study concludes that fish either have separate but coupled FEO and LEO's or a single oscillator that entrains to both food and light.
In 2008, further research was done to examine the presence of an FEO in Carassius auratus. When goldfish were first exposed to a 12:12 LD cycle and fed at 12:00. When moved to constant light, the fish exhibited food-anticipatory activity and had a free-running period of about 24 hours. Because the goldfish were able to remember feeding times when their light cycle was disrupted, this study suggests that the goldfish are able to remember daily feeding times and thus have a food entrainable oscillator, though its location remains unknown.
References
Circadian rhythm | Food-entrainable oscillator | [
"Biology"
] | 3,701 | [
"Behavior",
"Sleep",
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71,773,546 | https://en.wikipedia.org/wiki/Ministry%20of%20Electricity%20and%20Energy%20%28Yemen%29 | The Ministry of Electricity and Energy () is a cabinet ministry of Yemen.
Ministers
The current minister is Mana'a Saleh Yaslam, (28 July 2022– )
Anwar Mohamed Ali Kalshat, ( 18 December 2020– 27 July 2022)
See also
Cabinet of Yemen
References
Government ministries of Yemen | Ministry of Electricity and Energy (Yemen) | [
"Engineering"
] | 65 | [
"Energy organizations",
"Energy ministries"
] |
71,774,065 | https://en.wikipedia.org/wiki/VV%20Ursae%20Majoris | VV Ursae Majoris is a binary star system in the northern circumpolar constellation of Ursa Major, abbreviated VV UMa. It is a variable star system with a brightness that cycles around an apparent visual magnitude of 10.19, making it too faint to be visible to the naked eye. The system is located at a distance of approximately 1,500 light years based on parallax measurements.
This star was found to be variable by H. K. Gitz in 1936 based on photographic plates taken in Moscow, then S. Kaho published an ephemeris in 1939 using observed minima. In 1950, O. Struve computed the orbital elements for a single-lined spectroscopic binary system with a short orbital period of just . He found a stellar classification of A0V for the primary component. P. Broglia and P. Conconi analyzed the light curve of the system in 1977, and determined this to be a semidetached binary with the secondary component being significantly less massive than the primary. In 1996, V. Simon found a periodic variation in the system minima with a cycle length of 22 years. He proposed that this variation is being driven by a third component in the system.
This is an eclipsing binary; a semi-detached Algol-type system. The best fit spectral type for the primary component is A1.5–2V, matching an A-type main-sequence star. The secondary is a cooler, overluminous, late G-type star; it is a slightly evolved subgiant star that is filling its Roche lobe. The system displays an intrinsic low amplitude variability, which is probably coming from the primary. Multiple pulsation periods have been detected. There is no evidence of an infrared excess.
The light-travel time effect provides information about the properties of the purported third component in the system. It has 0.787 times the mass of the Sun and is orbiting at a distance of from the inner pair with an eccentricity of 0.35 and a period of .
References
Further reading
A-type main-sequence stars
G-type subgiants
Algol variables
Eclipsing binaries
Pulsating variables
Ursa Major
Durchmusterung objects
047279
Ursae Majoris, VV | VV Ursae Majoris | [
"Astronomy"
] | 473 | [
"Ursa Major",
"Constellations"
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71,774,250 | https://en.wikipedia.org/wiki/One%20Life%20%282023%20film%29 | One Life is a 2023 biographical drama film directed by James Hawes. Based on the true story of British humanitarian Nicholas Winton, the film alternates between following Anthony Hopkins as a 79-year old Winton reminiscing on his past, and Johnny Flynn as a 29-year old Winton who successfully helps 669 predominantly Jewish children in German-occupied Czechoslovakia to hide and flee in 1938–39, just before the beginning of World War II. Helena Bonham Carter, Lena Olin, Romola Garai, Alex Sharp and Jonathan Pryce co-star in supporting roles.
One Life had its world première at the Toronto International Film Festival on 9 September 2023, and its European première at the 2023 London Film Festival. It was released in the United Kingdom on 1 January 2024 by Warner Bros. Pictures, and later in the United States on 15 March 2024 by Bleecker Street. The film received mostly positive reviews, with praise for the performances of the cast, particularly Hopkins and Bonham Carter.
Plot
When 29-year-old London stockbroker Nicholas Winton visits Czechoslovakia in 1938, just weeks after the Munich Agreement was signed, he encounters families in Prague who had fled the rise of the Nazis in Germany and Austria. They are living in poor conditions, with little or no shelter or food and in fear of the invasion of the Nazis. Winton is introduced to Doreen Warriner, head of the Prague office of the British Committee for Refugees from Czechoslovakia (BCRC).
Horrified by the conditions in the refugee camps, Winton decides to save Jewish children himself. Actively supported by his mother Babette, herself a German-Jewish migrant who has since converted to the Church of England, he overcomes bureaucratic hurdles, collects donations and looks for foster families for the children brought to England. Many of them are Jews who are at imminent risk of deportation. A race against time begins as it is unclear how long the borders will remain open before a probable Nazi invasion.
Fifty years later, in 1988, Winton, now 79 years old, cleans up some of the clutter in his office, which his wife Grete asked him to do. He finds his old documents in which he recorded his work for the BCRC, with photos and lists of both the children they wanted to bring to safety and those they successfully saved. Winton still blames himself for not being able to rescue more.
At lunch with his old friend Martin, Winton thinks about what he should do with his main scrapbook, full of documents. He is considering donating them to a Holocaust museum, but at the same time he wants to draw some attention to the current plight of refugees as he continues working for the underpriviledged, so he decides against it.
The documents end up in the hands of the That's Life! production team, a TV show produced by the BBC with presenter Esther Rantzen. Winton is invited onto the show and asked to sit in the audience. That's Life surprises Winton by inviting some of the children he helped save onto the show to meet him.
A short time after the show airs, Winton is invited back, as the public response was overwhelming. This time, he and his wife are shown that most members of the studio audience directly owe their lives to his humanitarian effort. As of the production date of the film, over 6,000 people are alive thanks to Winton.
Cast
Production
In September 2020 Anthony Hopkins and Johnny Flynn were announced as being attached to a biopic about Sir Nicholas Winton called ‘’One Life’’. From a Lucinda Coxon and Nick Drake screenplay, Aisling Walsh was set to direct with See-Saw Films and BBC Film producing through executive producers Rose Garnett and Simon Gillis, and producers Iain Canning, Emile Sherman, and Joanna Laurie. FilmNation Entertainment and Cross City Films were to be managing international sales. In September 2022 it was revealed that James Hawes was attached to direct his feature film debut while Helena Bonham Carter had joined the cast as Winton’s mother, Babi Winton. It was also revealed that Guy Heeley was on board as producer and that the screenplay was based on the book ‘’If It’s Not Impossible…The Life of Sir Nicholas Winton,’’ written by his daughter Barbara Winton. Also announced as joining the cast were Jonathan Pryce, Romola Garai and Alex Sharp. Filming took place in London in September 2022, with principal photography also taking place in Prague.
Winton’s daughter requested that Hopkins should play her father. Hopkins read the script and accepted the part. Winton’s son praised Hopkins’ portrayal of his father. One survivor called the film a “fitting tribute”. The extras making up the recreation of the show’s audience are the actual children of those Winton had saved.
Critical response
Ian Freer in Time Out described it as a "remarkable World War II story told conventionally but elevated by a superb Anthony Hopkins". In The Guardian, Peter Bradshaw wrote "You'd need a heart of stone not to be touched by this extraordinary true story". Reviewing the film for The Observer, Wendy Ide gave the film three out of five stars.
Robbie Collin of The Daily Telegraph gave the film four out of five stars. The Spectators Deborah Ross praised the themes, performances and the film's message. Clarisse Loughrey of The Independent offered a more mixed review, though praised Hopkins' performance.
Writing for The Guardian, Matthew Reisz, whose father was one of the children Winton had saved, felt the film betrayed Winton. Nicola Gissing, another descendant of a saved child, wrote a letter to the paper in response, defending the film.
Controversy
Despite rescuing predominantly Jewish children, on the BBC Film website this fact was omitted. Cinema operators in the UK therefore mentioned in their advertising for One Life that Nicholas Winton had saved "children from Central Europe". Following protests, BBC Film changed the film's description, writing instead that Winton had saved "predominantly Jewish" children.
Awards
One Life won Cinema for Peace Dove for The Most Valuable Film of the Year 2024 in Berlin.
References
External links
2020s British films
2020s English-language films
2023 biographical drama films
British biographical drama films
British historical drama films
British war drama films
Films about Jews and Judaism
Films scored by Hauschka
Films directed by James Hawes
Films set in the 1930s
Films shot in London
Films shot in Prague
See-Saw Films films
BBC Film films
FilmNation Entertainment films
Warner Bros. films
World War II films based on actual events
Rescue of Jews during the Holocaust
English-language historical drama films
English-language biographical drama films | One Life (2023 film) | [
"Biology"
] | 1,365 | [
"Rescue of Jews during the Holocaust",
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71,775,593 | https://en.wikipedia.org/wiki/Resilience%20engineering | Resilience engineering is a subfield of safety science research that focuses on understanding how complex adaptive systems cope when encountering a surprise. The term resilience in this context refers to the capabilities that a system must possess in order to deal effectively with unanticipated events. Resilience engineering examines how systems build, sustain, degrade, and lose these capabilities.
Resilience engineering researchers have studied multiple safety-critical domains, including aviation, anesthesia, fire safety, space mission control, military operations, power plants, air traffic control, rail engineering, health care, and emergency response to both natural and industrial disasters. Resilience engineering researchers have also studied the non-safety-critical domain of software operations.
Whereas other approaches to safety (e.g., behavior-based safety, probabilistic risk assessment) focus on designing controls to prevent or mitigate specific known hazards (e.g., hazard analysis), or on assuring that a particular system is safe (e.g., safety cases), resilience engineering looks at a more general capability of systems to deal with hazards that were not previously known before they were encountered.
In particular, resilience engineering researchers study how people are able to cope effectively with complexity to ensure safe system operation, especially when they are experiencing time pressure. Under the resilience engineering paradigm, accidents are not attributable to human error. Instead, the assumption is that humans working in a system are always faced with goal conflicts, and limited resources, requiring them to constantly make trade-offs while under time pressure. When failures happen, they are understood as being due to the system temporarily being unable to cope with complexity. Hence, resilience engineering is related to other perspectives in safety that have reassessed the nature of human error, such as the "new look", the "new view", "safety differently", and Safety-II.
Resilience engineering researchers ask questions such as:
What can organizations do in order to be better prepared to handle unforeseeable challenges?
How do organizations adapt their structure and behavior to cope effectively when faced with an unforeseen challenge?
Because incidents often involve unforeseen challenges, resilience engineering researchers often use incident analysis as a research method.
Resilience engineering symposia
The first symposium on resilience engineering was held in October 2004 in Soderkoping, Sweden. It brought together fourteen safety science researchers with an interest in complex systems.
A second symposium on resilience engineering was held in November 2006 in Sophia Antipolis, France. The symposium had eighty participants. The Resilience Engineering Association, an association of researchers and practitioners with an interest in resilience engineering, continues to hold bi-annual symposia.
These symposia led to a series of books being published (see Books section below).
Themes
This section discusses aspects of the resilience engineering perspective that are different from traditional approaches to safety.
Normal work leads to both success and failure
The resilience engineering perspective assumes that the nature of work which people do within a system that contributes to an accident is fundamentally the same as the work that people do that contributes to successful outcomes. As a consequence, if work practices are only examined after an accident and are only interpreted in the context of the accident, the result of this analysis is subject to selection bias.
Fundamental surprise
The resilience engineering perspective posits that a significant number of failure modes are literally inconceivable in advance of them happening, because the environment that systems operate in are very dynamic and the perspectives of the people within the system are always inherently limited. These sorts of events are sometimes referred to as fundamental surprise. Contrast this with the approach of probabilistic risk assessment which focuses on evaluate conceivable risks.
Human performance variability as an asset
The resilience engineering perspective holds that human performance variability has positive effects as well as negative ones, and that safety is increased by amplifying the positive effects of human variability as well as adding controls to mitigate the negative effects. For example, the ability of humans to adapt their behavior based on novel circumstances is a positive effect that creates safety. As a consequence, adding controls to mitigate the effects of human variability can reduce safety in certain circumstances
The centrality of expertise and experience
Expert operators are an important source of resilience inside of systems. These operators become experts through previous experience at dealing with failures.
Risk is unavoidable
Under the resilience engineering perspective, the operators are always required to trade-off risks. As a consequence, in order to create safety, it is sometimes necessary for a system to take on some risk.
Bringing existing resilience to bear vs generating new resilience
The researcher Richard Cook distinguishes two separate kinds of work that tend to be conflated under the heading resilience engineering:
Bringing existing resilience to bear
The first type of resilience engineering work is determining how to best take advantage of the resilience that is already present in the system. Cook uses the example of setting a broken bone as this type of work: the resilience is already present in the physiology of bone, and setting the bone uses this resilience to achieving better healing outcomes.
Cook notes that this first type of resilience work does not require a deep understanding of the underlying mechanisms of resilience: humans have been setting bones long before the mechanism by which bone heals was understood.
Generating new resilience
The second type of resilience engineering work involves altering mechanisms in the system in order to increase the amount of the resilience. Cook uses the example of new drugs such as Abaloparatide and Teriparatide, which mimic Parathyroid hormone-related protein and are used to treat osteoporosis.
Cook notes that this second type of resilience work requires a much deeper understanding of the underlying existing resilience mechanisms in order to create interventions that can effectively increase resilience.
Hollnagel perspective
The safety researcher Erik Hollnagel views resilient performance as requiring four systemic potentials:
The potential to respond
The potential to monitor
The potential to learn
The potential to anticipate.
This has been described in a White Paper from Eurocontrol on Systemic Potentials Management https://skybrary.aero/bookshelf/systemic-potentials-management-building-basis-resilient-performance
Woods perspective
The safety researcher David Woods considers the following two concepts in his definition of resilience:
graceful extensibility: the ability of a system to develop new capabilities when faced with a surprise that cannot be dealt with effectively with a system's existing capabilities
sustained adaptability: the ability of a system to continue to keep adapting to surprises, over long periods of time
These two concepts are elaborated in Woods's theory of graceful extensibility.
Woods contrasts resilience with robustness, which is the ability of a system to deal effectively with potential challenges that were anticipated in advance.
The safety researcher Richard Cook argued that bone should serve as the archetype for understanding what resilience is in the Woods perspective. Cook notes that bone has both graceful extensibility (has a soft boundary at which it can extend function) and sustained adaptability (bone is constantly adapting through a dynamic balance between creation and destruction that is directed by mechanical strain).
In Woods's view, there are three common patterns to the failure of complex adaptive systems:
decompensation: exhaustion of capacity when encountering a disturbance
working at cross purposes: when individual agents in a system behave in a way that achieves local goals but goes against global goals
getting stuck in outdated behaviors: relying on strategies that were previously adaptive but are no longer so due to changes in the environment
Resilient Health care
In 2012 the growing interest for resilience engineering gave rise to the sub-field of Resilient Health Care. This led to a series of annual conferences on the topic that are still ongoing as well as a series of books, on Resilient Health Care, and in 2022 to the establishment of the Resilient Health Care Society (registered in Sweden). (https://rhcs.se/)
Books
Resilience Engineering: Concepts and Precepts by David Woods, Erik Hollnagel, and Nancy Leveson, 2006.
Resilience Engineering in Practice: A Guidebook by Jean Pariès, John Wreathall, and Erik Hollnagel, 2013.
Resilient Health Care, Volume 1: Erik Hollnagel, Jeffrey Braithwaite, and Robert L. Wears (eds), 2015.
Resilient Health Care, Volume 2: The Resilience of Everyday Clinical Work by Erik Hollnagel, Jeffrey Braithwaite, Robert Wears (eds), 2015.
Resilient Health Care, Volume 3: Reconciling Work-as-Imagined and Work-as-Done by Jeffrey Braithwaite, Robert Wears, and Erik Hollnagel (eds), 2016.
Resilience Engineering Perspectives, Volume 1: Remaining Sensitive to the Possibility of Failure by Erik Hollnagel, Christopher Nemeth, and Sidney Dekker (eds.), 2016.
Resilience Engineering Perspectives, Volume 2: Remaining Sensitive to the Possibility of Failure by Christopher Nemeth, Erik Hollnagel, and Sidney Dekker (eds.), 2016.
Governance and Control of Financial Systems: A Resilience Engineering Perspective by Gunilla Sundström and Erik Hollnagel, 2018.
References
Safety engineering
Hazard analysis | Resilience engineering | [
"Engineering"
] | 1,966 | [
"Safety engineering",
"Systems engineering",
"Hazard analysis",
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71,775,978 | https://en.wikipedia.org/wiki/Cognitive%20systems%20engineering | Cognitive systems engineering (CSE) is a field of study that examines the intersection of people, work, and technology, with a focus on safety-critical systems. The central tenet of cognitive systems engineering is to treat a collection of people and technology as a single unit, one that is capable of performing cognitive work. This unit is referred to as a joint cognitive system.
CSE draws on concepts from cognitive psychology and cognitive anthropology, such as Edwin Hutchins's distributed cognition, James Gibson's ecological theory of visual perception, Ulric Neisser's perceptual cycle, and William Clancey's situated cognition. CSE techniques include cognitive task analysis and cognitive work analysis.
History
Cognitive systems engineering emerged in the wake of the Three Mile Island (TMI) accident. At the time, existing theories about safety were unable to explain how the operators at TMI could be confused about what was actually happening inside of the plant.
Following the accident, Jens Rasmussen did early research on cognitive aspects of nuclear power plant control rooms. This work influenced a generation of researchers who would later come to be associated with cognitive systems engineering, including Morten Lind, Erik Hollnagel, and David Woods.
Following the publication of a textbook on cognitive systems engineering by Kim Vicente in 1999 the techniques employed to establish a cognitive work analysis (CWA) were used to aid the design of any kind of system were humans have to interact with technology. The tools outlined by Vicente were not tried and tested, and there are few if any published accounts of the five phases of analysis being implemented.
"Cognitive systems engineering" vs "Cognitive engineering"
The term "cognitive systems engineering" was introduced in a 1983 paper by Hollnagel and Woods.
Although the term cognitive engineering had already been introduced by Don Norman, Hollnagel and Woods deliberately introduced new terminology. They were unhappy with the framing of the term cognitive engineering, which they felt focused too much on improving the interaction between humans and computers, through the application of cognitive science. Instead, Hollnagel and Woods wished to emphasize a shift in focus from human-computer interaction to joint cognitive systems as the unit of analysis.
Despite the intention by Hollnagel and Woods to distinguish cognitive engineering from cognitive systems engineering, some researchers continue to use the two terms interchangeably.
Themes
Joint cognitive systems
As mentioned in the Origins section above, one of the key tenets of cognitive systems engineering is that the base unit of analysis is the joint cognitive system. Instead of viewing cognitive tasks as being done only by individuals, CSE views cognitive work as being accomplished by a collection of people coordinating with each other and using technology to jointly perform cognitive work as a system.
Studying work in context
CSE researchers focus their studies on work in situ, as opposed to studying how work is done in controlled laboratory environments. This research approach, known as macrocognition, is similar to the one taken by naturalistic decision-making. Examples of studies of work done in context include Julian Orr's ethnographic studies of copy machine technicians, Lucy Suchman's ethnographic studies of how people use photocopiers, Diane Vaughan's study of engineering work at NASA in the wake of the Space Shuttle Challenger disaster, and Scott Snook's study of military work in the wake of the 1994 Black Hawk shootdown incident.
Coping with complexity
A general thread that runs through cognitive systems engineering research is the question of how to design joint cognitive systems that can deal effectively with complexity, including common patterns in how such systems can fail to deal effectively with complexity.
Anomaly response
As mentioned in the Origins section above, CSE researchers were influenced by TMI. One specific application of coping with complexity is the work that human operators must do when they are supervising a process such as nuclear power plant, and they must then deal with a problem that arises. This work is sometimes known as anomaly response or dynamic fault management. This type of work often involves uncertainty, quickly changing conditions, and risk tradeoffs in deciding what remediation actions to take.
Coordination
Because joint cognitive systems involve multiple agents that must work together to complete cognitive tasks, coordination is another topic of interest in CSE. One specific example is the notion of common ground and its implications for building software that can contribute effectively as agents in a joint cognitive system.
Cognitive artifacts
CSE researchers study how people use technology to support cognitive work and coordinate this work across multiple people. Examples of such cognitive artifacts, which have been studied by researchers, include "the bed book" used in intensive care units, "voice loops" used in space operations, "speed bugs" used in aviation, drawings and sketches in engineering work, and the various tools used in marine navigation.
Of particular interest to CSE researchers is how computer-based tools influence joint cognitive work, in particular the impact of automation, and computerized interfaces used by system operators.
Founders and Foundational Contributors
Erik Hollnagel*
David Woods*
Robert Hoffman
Philip Smith
Jens Rasmussen
Emily Patterson
Laura Millitello
Books
Cognitive Systems Engineering: The Future for a Changing World by Philip J. Smith and Robbert R. Hoffman, eds. 2017
Joint Cognitive Systems: Patterns in Cognitive Systems Engineering by David Woods and Erik Hollnagel, 2005. 978-0849328213
Joint Cognitive Systems: Foundations of Cognitive Systems Engineering by Erik Hollnagel and David Woods, 2005. 978-0367864156
Cognitive Systems Engineering by Jens Rasmussen, Annelise Mark Pejtersen, and L.P. Goodstein, 1994.
See also
Cognitive work analysis
Ecological interface design
References
External links
Journals
Cognition, Technology & Work
International Journal of Human-Computer Studies
Ergonomics
Computer Supported Cooperative Work (CSCW): The Journal of Collaborative Computing and Work Practices
Systems engineering | Cognitive systems engineering | [
"Engineering"
] | 1,178 | [
"Systems engineering"
] |
71,779,078 | https://en.wikipedia.org/wiki/Alexis%20Ir%C3%A9n%C3%A9e%20du%20Pont | Alexis Irénée du Pont (February 14, 1816 – August 23, 1857) was an American business executive who ran the Eleutherian Mills gunpowder factory in Delaware. He was fatally injured along with five of his employees in an accidental explosion at the powder mills. He was the youngest child of Éleuthère Irénée du Pont, founder of E. I. du Pont de Nemours & Company.
Life and career
Born in New Castle County, Delaware, Alexis Irénée du Pont attended Mount Airy College in Germantown, Pennsylvania, and the New Haven Gymnasium in Connecticut from 1829 to 1831. Classmates included his nephew, James Irénée Bidermann, the only child of his father's business partner, Jacques Antoine Bidermann, and his sister, Evelina Gabrielle du Pont. Alexis Irénée completed scientific studies at the University of Pennsylvania from 1831 to 1835, though he never received his degree.
In December 1836, he married Joanna Maria Smith (1815–1876), daughter of Philadelphia merchant Francis Gurney Smith and sister of physician Thomas Mackie Smith, who had recently married Alexis Irénée's sister, Eleuthera du Pont Smith. Alexis Irénée and Joanna had eight children, including Francis Gurney du Pont, Eugène du Pont, and Alexis Irénée du Pont Jr.
Alexis Irénée du Pont became a partner in E. I. du Pont de Nemours & Company in 1837 and continued in this capacity until his death on August 23, 1857, having been fatally injured in an explosion at the powder mills a day earlier.
References
1816 births
1857 deaths
Alexis Irénée
People from New Castle County, Delaware
University of Pennsylvania alumni
19th-century American businesspeople
American business executives
Deaths from explosion | Alexis Irénée du Pont | [
"Chemistry"
] | 347 | [
"Deaths from explosion",
"Explosions"
] |
71,779,599 | https://en.wikipedia.org/wiki/Abhijit%20Sen%20%28physicist%29 | Abhijit Sen is Emeritus Scientist and INSA fellow, Sr. Professor, of the Institute for Plasma Research, Chandrasekhar Chair. Sen has published more than 300 research paper in reputed journals.
Education
Sen received a National Merit Scholarship from the Government of India during his education (1962–66). Sen completed his Bachelor of Science at Gujarat University in Physics in 1963. He later completed both a Master of Science and Doctor of Philosophy in Physics at the University of Tennessee in 1971. Following his doctoral studies, Sen became a Postdoctoral researcher at Oak Ridge National Laboratory.
Award and honours
Sen's awards include:
Young Scientist award from Indian National Science Academy
Fellow, Gujarat Science Society
Fellow of Indian Academy of Sciences
Fellow of National Academy of Sciences, India
Fellow of Indian National Science Academy
Fellow of American Physical Society
Fellow of Institute of Physics
Senior Associate of International Centre for Theoretical Physics
Science leadership
Sen is member of many organisations
Chairman of International Union of Pure and Applied Physics
Chairman of board of governors Indian Institute of Geomagnetism
Member Editorial board of Plasma Sources Science and Technology, Plasma Physics and Controlled Fusion, Nuclear Fusion (journal), Pramana (journal), Indian Journal of Physics
Member Academic Council Visva-Bharati University Indian Institute of Geomagnetism
Member Science and technology advisory committee ITER
References
Living people
1943 births
Indian physicists
Indian plasma physicists
Plasma physicists
Fellows of the American Physical Society | Abhijit Sen (physicist) | [
"Physics"
] | 283 | [
"Plasma physicists",
"Plasma physics"
] |
71,780,252 | https://en.wikipedia.org/wiki/Tank%20cascade%20system | The tank cascade system () is an ancient irrigation system spanning the island of Sri Lanka. It is a network of thousands of small irrigation tanks () draining to large reservoirs that store rainwater and surface runoff for later use. They make agriculture possible in the dry-zone, where periods of drought and flooding otherwise make it difficult to support paddy fields and livestock.
Originating in the 1st millennium BCE, the system was designated as a Globally Important Agricultural Heritage System by the United Nations Food and Agriculture Organization in 2017. Centralized bureaucratic management of large-scale systems was implemented from the 3rd to the 13th centuries. Small-scale systems continued to be well-maintained up until the abolishment of compulsory labor, following British consolidation of control over the island. Efforts since independence to rehabilitate the tanks have resulted in much of the system being restored, as well as the addition and integration of new reservoirs. The reservoirs total to 2.7% of the country's surface area and have a significant effect on the ecology of the island.
Etymology
A catchment site within the system is referred to as a () in Sinhala, and this term is translated into English as "tank".
These tanks are connected in a series, referred to as a cascade, so that an ephemeral waterflow can be used, stored for future use, or conveyed elsewhere. The native term in Sinhala for a cascade is , which is a compound word combining ("hanging") and ("next to one another").
Geography
The tank cascade system is largely located in the semi-arid north-central section of the island, which experiences equatorial heat, limited freshwater, and erratic rainfall patterns. The monsoon cycle in the region, coupled with low water retention in the soils of the region, results in minimal groundwater storage capacity, high rates of evaporation, and low or variable precipitation, meaning that "in this hard rock region...no stable human settlement would have been possible without recourse to the storage of surface water in small tanks." Granite and charnockite underlie in this area, decreasing permeability. The "undulating topography" of the island's dry zone is also appropriate for pond or reservoir construction, with small dams being able to create large reservoirs.
Overall, Sri Lanka has 80 major dams and 18,000 extant tanks. Between 10,000 and 14,000 tanks are in active use as irrigation sources; the majority of these hold water in the north-central lowland dry zone. The total surface area of all reservoirs in Sri Lanka was estimated in 1988 to be , of the country's area. Of this, 39,000 hectares correspond to just 44 major ancient reservoirs.
History
Whereas the agriculture of Fertile Crescent arose from stored water in low bottomland soil, and the agriculture of ancient Egypt was dependent on retained Nile River flood waters, ancient Sri Lankans used a chain of reservoir systems as their water source. Sri Lanka has been called a "hydraulic civilization." Similar ancient water engineering projects in tropical and subtropical climates include the qanats of Iran, oases in the Near East and North Africa, and the Gurganj Dam of Amu Darya.
Researchers theorise that the evolution of the tank cascade began with rain-fed agriculture and then became increasingly sophisticated beginning with diverting rivulets, then permanent rivers, followed by a leap forward with the construction of spillways, weirs and ultimately sluices, then the construction of reservoirs, until, at the apogee of development, ancient Sri Lankans were able to successfully dam up perennial rivers and use the water as they saw fit. Historic uses of the tank cascade system included human needs (drinking water, sanitation, food production), ecosystem enrichment, urban development, administrative boundary setting ("water cordons"), and natural disaster mitigation.
Rainwater reservoirs were being constructed on the island as early as 300 BCE—there are assertions that Sorabora Wewa in Mahiyangana was constructed by the yaksha spirits before the theory postulated as the Indo-Aryan migration to the island—and an estimated total of 30,000 tanks have been built over the history of Sri Lanka.
The existence of what is now called the tank cascade system is recorded in the Dīpavaṃsa and the two Mahāvaṃsa chronicles, which describe tanks, ponds, water holes, dams, canals, irrigation funding grants, irrigation income, irrigation taxes, and irrigation laws.
An estimated 15,000 tanks were built between 300 and 1300 CE, during the Anuradhapura Kingdom (437 CE–845 CE) and Polonnaruwa kingdom (846 CE–1302 CE) eras. Sri Lanka irrigation engineers of this period were supposedly summoned or hired by other kingdoms for their expertise.
In the 9th century, bureaucracy to organise the irrigation system included a committee known as the Twelve Great Reservoirs.
The most famous surviving exemplars of the irrigation infrastructure used by Sri Lankan elites are the Abhayavapi rainwater reservoir in Anuradhapura built by Pandukabhaya (437–366 BCE) and the "lion rock" fortress Sigiriya, a UNESCO World Heritage Site. The only possible source of water at Sigiriya (which sits 360 meters atop the plain) is rainwater, which was cunningly managed through a network of pools, underground channels and drains.
Other historic landmarks of Sri Lanka water engineering include the lion pond of Mihinthale, the stone lotus pond of Polonnaruva, and the architecture of Kumara Pokuna, the royal baths of Parakramabahu the Great.
Thousands of modest tanks with hyperlocal catchment areas were built at the same time as "the larger and more impressive network of irrigation systems that [were]…controlled and directed by the kings and other higher echelons of the irrigation bureaucracy." The extensive tank cascade infrastructure incorporated local and regional Buddhist monasteries by providing them with their own irrigation access and related incomes. In contemporary Sri Lanka, "Buddhist monks of any given village…are often consulted on water management decisions and lead agro-based cultural festivities."
Eventually the tank cascade system entered a period of decline and partial abandonment. Maintenance of the system between the 1200s and the 1700s CE, considered the "dark ages of tank civilization," is poorly understood. Very little is known of this period as the historical record is thin, but the Rājākariya labour system may have been involved. Dutch colonial administrators (1640–1796 CE) mostly concerned themselves with cultivation of coastal areas and lucrative crops like cinnamon and seem to have ignored the inland tank cascade systems. During the British colonial period, the Rājākariya system was abolished and the tank cascade system seemingly suffered as a result.
In the late 1800s CE an effort was made to reclaim and reorganise the surviving remnants of the tank cascade system; water sluices were replaced on several hundred tanks, and restoration projects were initiated for larger elements including Yodha Ela canal, Kala Wewa tank, Kantale tank, Giant's Tank and Minneriya-Elahara. British records also tell of village irrigation managers creating sluices from hollow tree trunks or clay pots turned pipes.
The Sri Lankan Department of Agricultural Services has overseen irrigation-management groups, called Farmers Organizations, since 1979. Sri Lanka's current water management plan seeks to preserve the ecosystem and cultural benefits of the system while making large-scale investments in drinking water systems, sewage treatment plants, and commercial-industrial water infrastructure. In addition to the tank cascade system, surface irrigation has been used on the island since the mid-20th century. One source says "the tanks have been largely untouched since the 1970s with the development of large irrigation and hydropower schemes."
Similar historic tank cascade systems can be found in Tamil Nadu state in southern India and West Bengal state in eastern India.
Hydrology and function
Village tanks and cascades are "naturalized" and generally built with permeable natural materials rather than concreted in place. Tanks can be any size from small vernal pools to huge perennial lakes "thousands of hectares in surface area."
These tanks are connected into a series, the "cascade" or , so that an ephemeral waterflow can be used, stored for future use, or conveyed elsewhere. The water flows through channels and spillways within a small or medium-sized drainage area (called kiul ela and ranging in size from 13 to 26 km2, with an average size of 20 km2.).
The cascade network draws from or serves to a variety of reservoirs: pahala wewa (village tank), kulu wewa (forest tanks), pin wewa (temple tanks), olagam wewa (supplementary tanks), ilaha wewa (storage tanks), et al. Tanks are edged with earthen embankments (or bund) called wekandas with integrated water gates called kuto sorowwas, horowwas (sluice) or bisokotuwas (valve pit) that release water into the canal system. The extent or expanse of water in the reservoir is called diyagiluma; the “dry lakebed” or “meadow” or parkland that the cascade potentially fills with water is wew pitiya. Village livestock congregate at the wew pitiya in the dry season. The upland stream channels are called diya para, the drainage channel exiting a village tank and paddy field is called kiwul ela.
The upstream edge of the tank is usually planted with a protective treeline called gasgommana and a reed bed for filtration, called perahana; the downstream edge is planted with biodiverse "interceptor" vegetation called kattakaduwa, intended as a bioremediation trap for salts and other contaminants. The gosgommana may be planted with indigenous species including Bassia longifolia, Terminalia arjuna, Crateva adansonii and Diosoyros malabarica. Herbs and medicinal plants are grown in the upper thaulla area of the system, and vegetables are often grown on the mounded barriers that separate paddy fields.
Some upstream elements of the system were designed to trap sediment that could eventually block the canals, while other upstream "forest tanks" serve as watering holes to keep wildlife out of the human water supply. Still other tank elements are engineered to recharge the aquifer. Studies of similar tank cascade systems in India found that they increase well recharge by 40 per cent and decrease surface runoff by 75 per cent.
The cascade network can be understood as an integrated, human-managed ecosystem "where water and land resources are organized within the micro-catchments of the dry zone landscape, providing basic needs to human, floral and faunal communities through water, soil, air and vegetation."
Use
The system remains an important part of the modern Sri Lankan irrigation network, and supports much of the agriculture in the country. The stored water is mainly used for paddy field cultivation of Asian rice (Oryza sativa). The paddy fields are called wela; the fields closest to the water gate are called purara wela or purana vela, depending on transliteration (meaning old fields). The purara wela were originally communal. Fields further away are called akkara wela (acre field), and were often developed during the European colonial period, are privately owned, and have a less favourable water supply.
The farmers of the Sri Lankan paddy fields originally grew heritage rice varieties like Suwandal but have now largely transitioned to Green Revolution strains of rice.
There are more than 7,500 village-scale tanks in use today, along with many other reservoirs that are either larger or that are no longer used for traditional purposes.
Locals coordinate water use through Farmers Organizations and "appoint a person called Jala Palaka [water controller], who is supposed to release water according to the requirement of the farmers and the domestic users. The normal practice is that the water controller retains some water in the tank for domestic purposes."
Village water management practices vary and depend on the social structure of the community and "locally evolved" systems.
Historic village tanks had strict codes surrounding the use of the various bodies of water in the tank cascade system, with designated areas for bathing, cleaning, watering animals, laundry and so forth. In many districts, the village tank system provides drinking water through well recharge; the existence of a small to moderately sized tank raises the groundwater levels in the immediate environment. Farmers capitalise on this by digging a series of wells near the tank body, which they use to extract water for drinking and washing.
Larger reservoirs may have buildings or huts built along the shore, and may be used for freshwater fishing, hunting or poaching, and lotus flower picking, in addition to the typical agricultural and pastoral uses.
Development agencies hope that revitalising the system could both mitigate some of the negative effects of climate change and restore some of the comity lost to the Sri Lankan Civil War, although the system (which originated during a golden age of the Sinhalese culture) may be less nostalgic for neighbours of Tamil ethnicity or Muslim faith.
Kidney disease
Some districts of Sri Lanka have epidemic rates of Chronic Kidney Disease of Unknown Etiology (CKDu). Pollution of groundwater by chemical-agricultural runoff is a suspected factor; men are more likely than women to develop the condition.
Kidney disease rates are highest in areas that use water diverted from the Mahaweli River.
Ecological and sociological dimensions
Benefits of the tank cascade system include creating cooler microclimates that serve as wildlife habitats, encouraging biodiversity through the establishment of many ecological niches and ecotones, and establishing conditions for a "unique decentralized social system in Sri Lanka where farmers have held the highest social rank."
The tanks and connecting channels are used as water sources and habitat by both domestic livestock and indigenous wildlife, including Sri Lankan elephants.
A biodiversity survey of just one tank cascade system in the Malwathu Oya river watershed found that it supported approximately 400 plant and animal species.
The local tank cascade systems persisted and stabilised local communities even when changing regimes on the national level led to the decline of the "large-scale centrally managed" tank cascade systems.
Farmers who were interviewed about their relationship with the tank cascade system referenced the Theravada Buddhist principle of Pratītyasamutpāda, suggesting that the "concept of a plurality of causes directly underpins the interconnected eco-systems approach that farmers of the tank cascade system apply to water."
Active restoration of a tank cascade system to historic standards can be observed at Alisthana at the 112-kilometre post on A9 road.
Gallery
See also
Sri Lanka dry-zone dry evergreen forests
Qanat (Middle East and North Africa)
Johad (Northern India)
Minneriya National Park
Yala National Park
Kaudulla National Park
Pidurangala Vihara
Notes
References
External links
United Nations Development Programme: Ancient water tanks of Sri Lanka to adapt to a changing climate
P.B. Dharmasena agriculture and water management teaching slideshows
Google Scholar Vindanage small tank papers
Proposal - Globally Important Agricultural Heritage System (GIAHS) Designation: The Cascaded Tank Village System (CTVS) in the Dry Zone of Sri Lanka - report by Sri Lanka Ministry of Agriculture & FAO UN
Irrigation in Sri Lanka
Permaculture
Rainwater harvesting
Water supply
Environment of Sri Lanka
Globally Important Agricultural Heritage Systems
Dams in Sri Lanka
History of dams | Tank cascade system | [
"Chemistry",
"Engineering",
"Environmental_science"
] | 3,156 | [
"Hydrology",
"Water supply",
"Environmental engineering"
] |
71,780,289 | https://en.wikipedia.org/wiki/Simone%20Hochgreb | Simone Hochgreb is a Brazilian mechanical engineer whose research has concerned efficiency and pollution in internal combustion engines, and the structure of premixed flames. She is Professor of Experimental Combustion at the University of Cambridge, head of the reacting flows group at Cambridge, and a Fellow of Homerton College, Cambridge, where she is Director of Studies for Engineering.
Education and career
Hochgreb studied mechanical engineering at the University of São Paulo, where she earned a bachelor's degree in 1985. She completed a Ph.D. in mechanical and aerospace engineering in 1991 at Princeton University. Her dissertation An Experimental and Numerical Study on the Oxidation of Formaldehyde, was supervised by Frederick L. Dryer.
She became Bradley Foundation Assistant Professor of Mechanical Engineering at the Massachusetts Institute of Technology, where she worked from 1991 to 1999. After working more briefly for Sandia National Laboratories and for engineering consulting firm Exponent, she took her present position as professor at the University of Cambridge in 2002.
Recognition
Hochgreb won the Ralph R. Teetor Educational Award of SAE International in 1996, and the Royal Society Wolfson Research Merit Award in 2003.
She was named a Fellow of the Royal Aeronautical Society in 2011, and elected to the inaugural 2018 class of Fellows of The Combustion Institute, "for excellent experiments in combustion across fundamental and applied areas, including autoignition, instabilities and turbulent flows".
References
External links
Home page
Year of birth missing (living people)
Living people
Brazilian mechanical engineers
Women engineers
University of São Paulo alumni
Princeton University alumni
Fellows of Homerton College, Cambridge
Massachusetts Institute of Technology faculty
Members of the University of Cambridge Department of Engineering
Fellows of the Royal Aeronautical Society
Fellows of the Combustion Institute | Simone Hochgreb | [
"Chemistry"
] | 344 | [
"Fellows of the Combustion Institute",
"Combustion"
] |
71,781,428 | https://en.wikipedia.org/wiki/Robert%20P.%20Lattimer | Robert P. Lattimer (February 2, 1945 - ) is a retired chemist who worked for Lubrizol as an Advanced Materials research and development technical fellow. He is an advocate for including intelligent design in public science curriculum.
Education
Lattimer attended the University of Missouri where he earned a B.S. in chemistry. He obtained his doctoral degree in 1971 in physical/analytical chemistry from the University of Kansas.
Career
Lattimer worked for B.F. Goodrich and later Noveon and Lubrizol as a research chemist. He retired as a Senior Technical Fellow following nearly 40 years of service. His published work on mass spectrometry and polymer characterization and degradation have been widely cited. He is a past Vice-President of the American Society for Mass Spectrometry. Lattimer was Vice-Chairman of the 1985 Gordon Research Conference on Analytical Pyrolysis. His most cited work treated the subject of mass spectrometry of transition metal macrocycles.
Political Advocacy
Lattimer is a board member for the Eagle Forum of Ohio. He has advocated for pro-family issues in the state, and he has been the Science Issues Chairman. He advocated for including Intelligent Design in the Ohio Board of Education's state science curriculum. Lattimer was a founder of the advocacy group Science Excellence for All Ohioans (SEAO). He co-authored a book titled The Evolution Controversy. He is a signer of A Scientific Dissent from Darwinism.
Awards and recognition
1990 - Sparks–Thomas award
2008 - Melvin Mooney Distinguished Technology Award from the ACS Rubber Division
He is a recipient of an Eagle Award from Eagle Forum and a Wedge of Truth Award from IDnet.
References
1945 births
Polymer scientists and engineers
20th-century American engineers
Living people
Intelligent design advocates
University of Missouri alumni
University of Kansas alumni
Mass spectrometrists | Robert P. Lattimer | [
"Physics",
"Chemistry",
"Materials_science"
] | 379 | [
"Physical chemists",
"Spectrum (physical sciences)",
"Biochemists",
"Mass spectrometrists",
"Mass spectrometry",
"Polymer chemistry",
"Polymer scientists and engineers"
] |
71,783,329 | https://en.wikipedia.org/wiki/Tamir%20Tuller | Tamir Tuller is an Israeli engineer, a computer scientist, and a systems and synthetic biologist. He is a professor, incumbent of the Chair in Computational Synthetic Biology, and the director of Tel Aviv University's Laboratory of Computational Systems and Synthetic Biology. As of February 2022, Tuller has authored over 150 peer-reviewed scientific journal articles and hundreds of additional types of publications and patents. In addition, he is the founder and primary instructor of the International Genetically Engineered Machine program at Tel Aviv University and an entrepreneur.
Research and career
Tuller is presently a Full Professor at the Tel-Aviv University in the Department of Biomedical Engineering and Edmond J. Safra centre for Bioinformatics. Prior to obtaining his current position, he also was an engineer at DSP group in VLSI chip design. He served as the co-founder and chief scientific officer of Synvaccine Ltd, and Imagindairy Ltd and as a consultant to various additional biotech companies.
Awards and honors
Tuller received the Juludan Research Prize from the Technion, Israel Institute of Technology in 2016.
Publications
As of February 2022, Tuller has authored over 150 peer-reviewed scientific journal articles and hundreds of additional types of publications and patents.
Accelerating Whole-Cell Simulations of mRNA Translation Using a Dedicated Hardware.
Estimating the predictive power of silent mutations on cancer classification and prognosis.
Algorithms for ribosome traffic engineering and their potential in improving host cells' titer and growth rate.
High-resolution modeling of the selection on local mRNA folding strength in coding sequences across the Tree of Life.
Solving the riddle of the evolution of Shine-Dalgarno based translation in chloroplasts.
Novel Insights into Gene Expression Regulation during Meiosis Revealed by Translation Elongation Dynamics.
ChimeraUGEM: unsupervised gene expression modeling in any given organism.
References
External links
Synthetic biologists
Israeli engineers
Israeli computer scientists
Israeli biologists
Israeli company founders
Living people
Year of birth missing (living people)
Technion – Israel Institute of Technology alumni
Tel Aviv University alumni
Academic staff of Tel Aviv University | Tamir Tuller | [
"Biology"
] | 428 | [
"Synthetic biology",
"Synthetic biologists"
] |
71,783,646 | https://en.wikipedia.org/wiki/Quantum%20Experiments%20using%20Satellite%20Technology | Quantum Experiment using Satellite Technology was launched in 2017 by the Raman Research Institute. In February 2021, the project demonstrated quantum communication for 50 m apart, and on 19 March 2021 for 300 m apart inline of sight in Space Applications Centre, which was done in coordination with the Indian Space Research Organisation, Indian Institute of Science and Tata Institute of Fundamental Research. Quantum Experiment using Satellite Technology is India's first project on satellite based long distance quantum communication.
Technical specifications
Indigenously developed NAVIC receiver for time synchronization
Gimbal mechanism system instead of large aperture telescope for optical alignment.
Shared quantum secure text.
Shared image transmission.
Quantum assisted two ways video conferencing at the Space Applications Centre and Physical Research Laboratory
It used robust and high brightness entangled photon source, used BBM92 protocol implementation NAVIC enabled synchronization polarization compensation technique.
It is hack proof as it uses quantum key distribution.
It uses quantum cryptography and carried out by Quantum information and computing (QuIC) lab .
References
Satellites
Quantum computing
Indian Space Research Organisation | Quantum Experiments using Satellite Technology | [
"Astronomy"
] | 214 | [
"Satellites",
"Outer space",
"Astronomy stubs",
"Spacecraft stubs"
] |
71,785,490 | https://en.wikipedia.org/wiki/Cercidospora%20macrospora | Cercidospora macrospora is a species of lichenicolous fungus in the genus Cercidospora but it has not been assigned to a family. It is known from the northern hemisphere.
Known host species include lichen of the genus Lecanora.
References
Dothideomycetes
Fungi described in 2004
Fungi of India
Lichenicolous fungi
Fungus species | Cercidospora macrospora | [
"Biology"
] | 78 | [
"Fungi",
"Fungus species"
] |
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