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62,338,906 | https://en.wikipedia.org/wiki/Categorical%20trace | In category theory, a branch of mathematics, the categorical trace is a generalization of the trace of a matrix.
Definition
The trace is defined in the context of a symmetric monoidal category C, i.e., a category equipped with a suitable notion of a product . (The notation reflects that the product is, in many cases, a kind of a tensor product.) An object X in such a category C is called dualizable if there is another object playing the role of a dual object of X. In this situation, the trace of a morphism is defined as the composition of the following morphisms:
where 1 is the monoidal unit and the extremal morphisms are the coevaluation and evaluation, which are part of the definition of dualizable objects.
The same definition applies, to great effect, also when C is a symmetric monoidal ∞-category.
Examples
If C is the category of vector spaces over a fixed field k, the dualizable objects are precisely the finite-dimensional vector spaces, and the trace in the sense above is the morphism
which is the multiplication by the trace of the endomorphism f in the usual sense of linear algebra.
If C is the ∞-category of chain complexes of modules (over a fixed commutative ring R), dualizable objects V in C are precisely the perfect complexes. The trace in this setting captures, for example, the Euler characteristic, which is the alternating sum of the ranks of its terms:
Further applications
have used categorical trace methods to prove an algebro-geometric version of the Atiyah–Bott fixed point formula, an extension of the Lefschetz fixed point formula.
References
Further reading
Category theory
Fixed-point theorems
Geometry | Categorical trace | [
"Mathematics"
] | 364 | [
"Theorems in mathematical analysis",
"Functions and mappings",
"Mathematical structures",
"Mathematical objects",
"Fixed-point theorems",
"Theorems in topology",
"Fields of abstract algebra",
"Category theory",
"Mathematical relations",
"Geometry"
] |
62,342,504 | https://en.wikipedia.org/wiki/All%20India%20Society%20for%20Electronics%20and%20Computer%20Technology | All India Society for Electronics and Computer Technology (AISECT) is a social enterprise established in 1985 to take computer education to the rural and semi-urban masses. It was established by Santosh Choubey. The organisation now operates in 28 states and four union territories of India, serving millions of people mostly in rural and semi-urban areas through its 23,000+ end-mile service delivery centres.
History
The society was established by Santosh Choubey and a few other youths in 1985 when computers were new to India. Computers became more useful and popular over the years but the rural and semi-urban masses of India were being left out from India's economic and digital growth story. AISECT realising the need to bridge the ICT gap and started developing computer education content in regional languages, starting with Hindi. It started opening computer training centres in rural districts and blocks of Madhya Pradesh in the early nineties after going through various reorganisations over the years, AISECT was officially registered as a cooperative society in the year 1997.
References
Information technology education
Educational organisations based in India
Educational institutions established in 1985
1985 establishments in Madhya Pradesh | All India Society for Electronics and Computer Technology | [
"Technology"
] | 230 | [
"Information technology",
"Information technology education"
] |
62,342,670 | https://en.wikipedia.org/wiki/MAMMA. | The Modernist Architects of Morocco Memorial Association (, ), or MAMMA., is an architectural heritage association based in Casablanca, Morocco. It's dedicated to the preservation of modernist and post-independence architectural heritage.
Activities
Modern Casablanca Map
In 2019, MAMMA., realized the Modern Casablanca Map project in collaboration with the Observatory Workshop (Collective Museum). The project consisted of creating a map and guidebook to Casablanca's modernist and post-independence architecture, as well as hosting guided tours and a temporary exhibition at the cupola of the Arab League Park.
Elie Azagury
On December 20, 2019, MAMMA. sponsored an event dedicated to the architectural legacy of Elie Azagury, the first Moroccan modernist architect. This event included guided tours of the Ibrahim Roudani School and a lecture hosted by the Saudi Library.
References
Cultural organizations based in Morocco
Architecture organizations | MAMMA. | [
"Engineering"
] | 178 | [
"Architecture organizations",
"Architecture"
] |
62,343,336 | https://en.wikipedia.org/wiki/Ove%20Christiansen | Ove Christiansen (born November 13, 1969, in Holstebro, Denmark) is professor of chemistry at the Department of Chemistry, Aarhus University (AU), Denmark. He is contributor to the DALTON program package and initiated the MidasCpp (Molecular Interactions Dynamics and Simulations in C++) program for the accurate description of nuclear dynamics with means of Coupled Cluster Theory.
Research
Ove Christiansen made important contributions to electronic structure theory by introducing the CC2 and CC3 method and by establishing a hierarchy of Coupled cluster electronic structure models: CCS, CC2, CCSD, CC3, etc..
He introduced contributions to response theory for the purpose of describing electronic excited states. Later he changed the emphasis of his main research interest towards vibrational structure theory and defined a variant of vibrational Coupled cluster (VCC) and developed the theoretical machinery for automatic derivation and implementation of VCC. Moreover, he defined vibrational response theory for various wave function types. All these progress is assembled in the publicly available MidasCpp program suite .
Academic career
Ove Christiansen received his PhD in Theoretical Chemistry under the supervision of Prof. Poul Jørgensen at Aarhus University Denmark in 1997. Afterwards he joined from 1997 to 1999 as Alexander von Humboldt fellow the group of Prof. Jürgen Gauß in Mainz Germany and later went to the University of Lund in Sweden, where he became a Docent in 2000. In 2002 he returned to Aarhus University as Associate Professor, became Professor MSO (Professor with special obligations) in 2013 and was promoted to a full Professor in 2018.
Awards
2013: EliteForsk award
2006: EURYI Award
References
1969 births
Living people
Theoretical chemists
Danish chemists
Academic staff of Aarhus University
Computational chemists
People from Holstebro | Ove Christiansen | [
"Chemistry"
] | 361 | [
"Quantum chemistry",
"Physical chemists",
"Computational chemists",
"Theoretical chemistry",
"Computational chemistry",
"Theoretical chemists"
] |
62,345,946 | https://en.wikipedia.org/wiki/Gem5 | The gem5 simulator is an open source discrete-event computer architecture simulator. It combines system-level and microarchitectural simulation, allowing users to analyze and test a multiplicity of hardware configurations, architectures, and software environments, without access or development of any hardware.
The simulator is capable of simulating modern operating system running on a simulator system and supports a variety of instruction set architectures (ISAs), including x86, ARM, RISC-V. gem5 comes with a library of pre-made components that conform to a modular design methodology allowing researchers to conduct experiments on a wide systems with relative ease. As such gem5 is used to in research tasks as diverse as processor design, the development of memory subsystems, and application performance optimization. In addition to research, gem5 serves as an important education tool, enabling educators to demonstrate to the impact computer architecture design decisions can have on computer system performance.
History
The gem5 simulator was born out of the merger of m5 (a detailed CPU simulator) and GEMS simulator (a detailed memory system simulator) in 2011.
Features and Capabilities
Multi-level Simulation: gem5 supports both system-level and detailed microarchitectural simulation.
Flexible Processor and System Modeling: gem5 can model a wide range of processor architectures, including x86, ARM, RISC-V, SPARC, and MIPS.
Configurable Memory Hierarchies: gem5 allows users to define custom cache and memory configurations for exploring different system setups.
Support for Full-System and Syscall Emulation: gem5 enables simulation of full-system software stacks, including OS and application code, or simplified syscall emulation for faster performance.
Modular Design: gem5 is highly modular, enabling researchers to plug in different models for CPUs, caches, interconnects, and other system components.
Extensive Library of Models: gem5 includes detailed models for CPUs (timing, atomic, in-order, and out-of-order), memory, interconnects, and peripheral devices.
Scalable Multi-core Simulation: gem5 supports single-core to complex multicore and multi-threaded architectures.
Scripting and Automation with Python: gem5 allows users to configure and control simulations using Python scripts, facilitating complex experiment setups via Python.
References
External links
Source Code
Simulation software
Software_using_the_BSD_license | Gem5 | [
"Technology"
] | 498 | [
"Computing stubs",
"Computer science",
"Computer science stubs"
] |
62,346,178 | https://en.wikipedia.org/wiki/S5-HVS1 | S5-HVS1 is an A-type main-sequence star notable as the fastest one detected as of November 2019, and has been determined to be traveling at . The star is in the Grus (or Crane) constellation in the southern sky, and about 29,000 light-years from Earth. According to astronomers, S5-HVS1 was ejected from the Milky Way galaxy after interacting with Sagittarius A*, the supermassive black hole at the center of the galaxy. It is possible that it was originally part of a binary system that was tidally disrupted by the supermassive black hole, causing it to be ejected. If this is the case, that it was flung out of the galaxy by the central black hole, it is then the first example of a star that has undergone the Hills mechanism.
The star's discovery has been credited to Sergey Koposov, assistant professor of physics at Carnegie Mellon University, as part of the Southern Stellar Stream Spectroscopic Survey (S5). The designation HVS1 refers to hypervelocity stars (HVS).
See also
List of star extremes
SDSS J090745.0+024507 – another fast moving star
US 708 – another fast moving star
References
External links
Runaway stars
Hypervelocity stars
Grus (constellation)
Astronomical objects discovered in 2019 | S5-HVS1 | [
"Astronomy"
] | 281 | [
"Grus (constellation)",
"Constellations"
] |
62,346,247 | https://en.wikipedia.org/wiki/Journal%20of%20Surveying%20Engineering | The Journal of Surveying Engineering is a quarterly peer-reviewed scientific journal published by the American Society of Civil Engineers. It covers traditional areas of surveying and mapping, as well as new developments such as satellite positioning and navigation, computer applications, and digital mapping. It was established in 1956 (when ASCE Transactions was split into 12 technical journals).
Abstracting and indexing
The journal abstracted and indexed in the Emerging Sources Citation Index and Scopus.
Current Editorial Broad
Editor:
Michael J. Olsen, Ph.D., M.ASCE, Oregon State University
Associate Editor:
Alireza Amiri-Simkooei, Ph.D., University of Isfahan
Sergio Baselga, Ph.D., M.ASCE, Universidad Politécnica de Valencia
Said M. Easa, Ph.D., P.E., M.ASCE, Ryerson University,
Toronto
Craig Glennie, Ph.D., P.E., University of Houston
Jen-Yu Han, Ph.D., M.ASCE, National Taiwan University
Editorial Board:
Bishwa N. Acharya, Ph.D., M.ASCE, EMI, Inc.
James M. Anderson, Ph.D., P.E., P.L.S., University of California, Berkeley
David Belton, Curtin University
Michael L. Dennis, Ph.D., P.E., R.L.S., M.ASCE, National Geodetic Survey
Robert Duchnowski, University of Warmia and Mazury in Olsztyn
Ahmed F. Elaksher, Ph.D., P.L.S., New Mexico State University
Andrew C. Kellie, P.L.S., M.ASCE, Murray State University
Andrzej Kobryń, Bialystok University of Technology
Thomas H. Meyer, Ph.D., M.ASCE, University of Connecticut
Chris Parrish, Aff.M.ASCE, Oregon State University
Jacek Paziewski, Ph.D., University of Warmia and Mazury in Olsztyn
Elena Rangelova, Ph.D., P.Eng., University of Calgary
David A. Rolbiecki, P.L.S., M.ASCE, State of Texas Adjutant General’s Department
Michael Starek, Ph.D., M.ASCE, Texas A&M University, Corpus Christi
Ergin Tari, Ph.D., Istanbul Technical University
Guoquan Wang, Ph.D., M.ASCE, University of Houston
Benjamin E. Wilkinson, Ph.D., University of Florida
Book Review Editor:
Boudewijn H.W. van Gelder, Ph.D., M.ASCE, Purdue University
References
External links
Engineering journals
American Society of Civil Engineers academic journals
Quarterly journals
English-language journals
Publications established in 1873
Surveying | Journal of Surveying Engineering | [
"Engineering"
] | 602 | [
"Surveying",
"Civil engineering"
] |
62,346,448 | https://en.wikipedia.org/wiki/Lefty%27s | Lefty's is a retail store on Pier 39 in San Francisco, specializing in products for left-handed people. It was opened in 2008 by Margaret Majua. However, the history of a left-handed store on Pier 39 dates back to 1975, with the opening of Left-Hand World, which closed ten years later. The product line, all designed by Majua, include stationery products, such as notebooks with the binding on the right side, and a pen which allows left-handed writers to see what they had just written without smearing it; cooking utensils for the left hand; and clothing with slogans for left-handers. Lefty's, which sells its products both in-store and online, is one of just a few stores for left-handed people worldwide, and currently the oldest.
References
External links
2008 establishments in California
Retail companies based in California
Handedness
Companies based in San Francisco
American companies established in 2008
Retail companies established in 2008 | Lefty's | [
"Physics",
"Chemistry",
"Biology"
] | 201 | [
"Behavior",
"Motor control",
"Chirality",
"Asymmetry",
"Handedness",
"Symmetry"
] |
62,346,846 | https://en.wikipedia.org/wiki/Mireille%20Kamariza | Mireille Kamariza is a Burundian-born American bioscientist and an Assistant Professor in the Bioengineering Department at the UCLA Henry Samueli School of Engineering and Applied Science. Previously, Kamariza was appointed as a Harvard Junior Fellow for her postdoctoral studies and she completed her doctoral studies in Biology at Stanford University. Her research considers the development of chemical biosensing tools, low cost point-of-care diagnostics, infectious diseases, and global health. In 2020, she was named as one of Chemical & Engineering News's Talented 12.
Early life
Kamariza was born in Burundi a few years before the Burundi Civil War. Kamariza became interested in science as a child, and enjoyed reading books about planets. Girls rarely attend college in Burundi, but Kamariza enrolled at a government-managed Catholic school.
During Kamariza's childhood, she often had to move due to the ongoing civil war. Kamariza observed the ravages that infectious diseases such as AIDS and malaria have on already vulnerable populations. But whilst malaria and AIDS receive significant media attention and funding, they are not the most lethal conditions in Africa. In 2015, tuberculosis killed 1.4 million people, considerably more than AIDS, and there is still significant stigma surrounding the disease.
In 2006, Kamariza and her brothers moved to San Diego, California. Together they lived close to San Diego Mesa College, where Kamariza took classes alongside working to support herself. Saloua Saidane, one of her professors, noticed her talent and suggested that she focused on her education. Following Saidane's advice, Kamariza quit her job at Safeway.
Kamariza transferred and completed her bachelor's degree in biochemistry at the University of California, San Diego. At UCSD, Kamariza and her colleagues established a peer-to-peer mentoring program that paired transfer students with current UCSD students. Her efforts inspired other initiatives at UCSD, including supporting transfer students in identifying research opportunities. Her impact on UCSD was recognised by her undergraduate dean David Artis, who referred to Kamariza as one of his "all-time favorite students". She was awarded an American Chemical Society (ACS) internship to work at the ACS headquarters.
Education and research
In 2012 Kamariza moved to the University of California, Berkeley, for her graduate studies in cell biology. She applied to join the research group of Carolyn R. Bertozzi. After earning her master's degree, Kamariza joined Stanford University as a graduate student, still working in the Bertozzi laboratory. Here she developed a new point of care diagnostic device for tuberculosis (TB). Tuberculosis is caused by the mycobacterium tuberculosis, a bacterium that has a cell wall so dense that it is difficult for drugs to penetrate. Trehalose is a chemical compound that is found in a range of living organisms that is used by mycobacterium tuberculosis as a scaffold. Kamariza developed DMN-Tre (4-N,N-dimethy-laminonaph-thal-i-mide-trehalose), a molecule that lights up when it is incorporated into the cell walls of mycobacteria. Her research was commercialised, and together with Bertozzi she founded OliLux Biosciences, a company that looks to develop low cost diagnostics for low-income countries. It was awarded a Bill & Melinda Gates Foundation grant to test their diagnostic devices in places with high levels of disease. She has tested it with small groups of patients in South Africa. In 2017 Kamariza was selected as one of Fortune magazine's World's Most Powerful Women.
Kamariza was appointed a Harvard Junior Fellow at Harvard University in 2019. She examines topics regarding precision medicine in global health. She was named one of Chemical & Engineering News's Talented 12 in 2020.
References
Burundian expatriates in the United States
Burundian scientists
1989 births
Stanford University alumni
University of California, San Diego alumni
San Diego Mesa College alumni
Harvard University faculty
Women biochemists
21st-century women scientists
Living people
Burundian women scientists | Mireille Kamariza | [
"Chemistry"
] | 852 | [
"Biochemists",
"Women biochemists"
] |
77,675,171 | https://en.wikipedia.org/wiki/Lazertinib | Lazertinib, sold under the brand name Lazcluze among others, is an anti-cancer medication used for the treatment of non-small cell lung cancer. It is a kinase inhibitor of epidermal growth factor receptor.
The most common adverse reactions include rash, nail toxicity, infusion-related reactions (amivantamab), musculoskeletal pain, edema, stomatitis, venous thromboembolism, paresthesia, fatigue, diarrhea, constipation, COVID-19 infection, hemorrhage, dry skin, decreased appetite, pruritus, nausea, and ocular toxicity.
Lazertinib was approved for medical use in South Korea in January 2021, in the United States in August 2024, and in the European Union in January 2025.
Medical uses
Lazertinib is indicated in combination with amivantamab for the first-line treatment of adults with locally advanced or metastatic non-small cell lung cancer with epidermal growth factor receptor exon 19 deletions or exon 21 L858R substitution mutations.
History
Efficacy was evaluated in MARIPOSA (NCT04487080), a randomized, active-controlled, multicenter trial of 1074 participants with exon 19 deletion or exon 21 L858R substitution mutation-positive locally advanced or metastatic non-small cell lung cancer and no prior systemic therapy for advanced disease. Participants were randomized (2:2:1) to receive lazertinib in combination with amivantamab, osimertinib monotherapy, or lazertinib monotherapy (an unapproved regimen for non-small cell lung cancer) until disease progression or unacceptable toxicity.
Society and culture
Legal status
Lazertinib was approved for medical use in the United States in August 2024.
In November 2024, the Committee for Medicinal Products for Human Use of the European Medicines Agency adopted a positive opinion, recommending the granting of a marketing authorization for the medicinal product Lazcluze, intended in combination with amivantamab, for the treatment of non-small cell lung cancer (NSCLC) with activating epidermal growth factor receptor (EGFR) exon 19 deletions or exon 21 L858R substitution mutations. The applicant for this medicinal product is Janssen-Cilag International NV. Lazertinib was approved for medical use in the European Union in January 2025.
Names
Lazertinib is the international nonproprietary name.
Lazertinib is sold under the brand name Lazcluze.
References
External links
Tyrosine kinase inhibitors
4-Morpholinyl compounds
Pyrimidines
Methoxy compounds
Anilides
Guanidines
Pyrazoles
Dimethylamino compounds | Lazertinib | [
"Chemistry"
] | 591 | [
"Guanidines",
"Functional groups"
] |
77,676,110 | https://en.wikipedia.org/wiki/List%20of%20star%20systems%20within%20150%E2%80%93200%20light-years | This is a list of star systems within 150–200 light years of Earth.
See also
List of star systems within 100–150 light-years
List of star systems within 200–250 light-years
References
Lists by distance
Star systems
Lists of stars | List of star systems within 150–200 light-years | [
"Physics",
"Astronomy"
] | 51 | [
"Lists by distance",
"Physical quantities",
"Distance",
"Astronomical objects",
"Star systems"
] |
77,676,319 | https://en.wikipedia.org/wiki/List%20of%20star%20systems%20within%20200%E2%80%93250%20light-years | This is a list of star systems within 200–250 light years of Earth.
See also
List of star systems within 150–200 light-years
List of star systems within 250–300 light-years
References
Lists by distance
Star systems
Lists of stars | List of star systems within 200–250 light-years | [
"Physics",
"Astronomy"
] | 51 | [
"Lists by distance",
"Physical quantities",
"Distance",
"Astronomical objects",
"Star systems"
] |
77,676,340 | https://en.wikipedia.org/wiki/List%20of%20star%20systems%20within%20250%E2%80%93300%20light-years | This is a list of star systems within 250–300 light years of Earth.
See also
List of star systems within 200–250 light-years
List of star systems within 300–350 light-years
References
Lists by distance
Star systems
Lists of stars | List of star systems within 250–300 light-years | [
"Physics",
"Astronomy"
] | 51 | [
"Lists by distance",
"Physical quantities",
"Distance",
"Astronomical objects",
"Star systems"
] |
77,676,412 | https://en.wikipedia.org/wiki/List%20of%20star%20systems%20within%20300%E2%80%93350%20light-years | This is a list of star systems within 300–350 light years of Earth.
See also
List of star systems within 250–300 light-years
List of star systems within 350–400 light-years
References
Lists by distance
Star systems
Lists of stars | List of star systems within 300–350 light-years | [
"Physics",
"Astronomy"
] | 51 | [
"Lists by distance",
"Physical quantities",
"Distance",
"Astronomical objects",
"Star systems"
] |
77,676,484 | https://en.wikipedia.org/wiki/List%20of%20star%20systems%20within%20350%E2%80%93400%20light-years | This is a list of star systems within 350–400 light years of Earth.
See also
List of star systems within 300–350 light-years
List of star systems within 400–450 light-years
References
Lists by distance
Star systems
Lists of stars | List of star systems within 350–400 light-years | [
"Physics",
"Astronomy"
] | 51 | [
"Lists by distance",
"Physical quantities",
"Distance",
"Astronomical objects",
"Star systems"
] |
77,676,491 | https://en.wikipedia.org/wiki/List%20of%20star%20systems%20within%20450%E2%80%93500%20light-years | This is a list of star systems within 450–500 light years of Earth.
See also
List of star systems within 400–450 light-years
References
Lists by distance
Star systems
Lists of stars | List of star systems within 450–500 light-years | [
"Physics",
"Astronomy"
] | 40 | [
"Lists by distance",
"Physical quantities",
"Distance",
"Astronomical objects",
"Star systems"
] |
77,676,512 | https://en.wikipedia.org/wiki/List%20of%20star%20systems%20within%20400%E2%80%93450%20light-years | This is a list of star systems within 400–450 light years of Earth.
See also
List of star systems within 350–400 light-years
List of star systems within 450–500 light-years
References
Lists by distance
Star systems
Lists of stars | List of star systems within 400–450 light-years | [
"Physics",
"Astronomy"
] | 51 | [
"Lists by distance",
"Physical quantities",
"Distance",
"Astronomical objects",
"Star systems"
] |
77,676,689 | https://en.wikipedia.org/wiki/NGC%207093 | NGC 7093 is an open cluster located in the Cygnus constellation. It was discovered by John Herschel on September 19, 1829. It is located at a distance of about 5,800 light-years from the Sun and 28,400 light-years from the Galactic Center.
References
7093
Cygnus (constellation)
Open clusters | NGC 7093 | [
"Astronomy"
] | 72 | [
"Cygnus (constellation)",
"Constellations"
] |
77,677,215 | https://en.wikipedia.org/wiki/Explosive%20ordnance%20disposal%20%28United%20States%20Army%29 | For other uses, see bomb disposal.
Explosive Ordnance Disposal (EOD) in the United States Army is the specialization responsible for detecting, identifying, evaluating, rendering safe, exploiting, and disposing of conventional, improvised, and chemical, biological, radiological, and nuclear (CBRN) explosive ordnance. It is a core competency of the US Army Ordnance Corps, along with Maintenance, Ammunition, and Explosive Safety.
The military occupational specialty (MOS) code is 89D for enlisted personnel. Officers have the area of concentration (AOC) of 89E, but earn the 90A AOC after the U.S. Army Captain's Career Course.
EOD support is provided during peace and war to US forces, allies, foreign partners, and Tribal, Federal, State, and local law enforcement. Examples of missions include:
Direct support to US Maneuver, Special Operations, Fires, and Aviation forces
Defense Support of Civil Authorities (DSCA)
Unexploded ordnance mitigation
United States Secret Service Very Important Person Protection Support Activity (VIPPSA)
Theater Security Cooperation
Humanitarian Mine Action (HMA)
CBRN mitigation
Counter-IED (CIED)
Additionally, the U.S. Army is the Lead Agent and Head of Delegation to the North Atlantic Treaty Organization (NATO) Counter Improvised Explosive Device and EOD Working Groups.
History
Explosive Ordnance Disposal has existed in various forms since the invention of explosives and industrial warfare. However, modern EOD formations largely trace their lineage to World War II, most notably during the Battle of Britain. Heavy aerial bombing of the United Kingdom by the German Luftwaffe left behind hundreds of tons of unexploded ordnance (UXO), then referred to as unexploded bombs (UXB). The British formed bomb squads to address the threat. Bombs that simply failed to function as design (duds) were relatively easy to dispose of but bombs with more sophisticated fuzes posed unique threats. Those that had time-delay fuzes, fuzes with anti-tamper or anti-remove devices, or those that incorporated anti-handling features caused high casualties that required a more professionalized force.
Recognizing this threat posed by UXO, the United States Army, Navy, and Marine Corps began sending volunteers to train on techniques at Melksham Royal Air Force (RAF) Station, Wiltshire, England, in 1940. Many of these volunteers were graduates of or would return to the US to attend the U.S. Naval Mine Disposal School at the Naval Gun Factory, Washington D.C. They would then form the first class of the newly established U.S. Bomb Disposal School at Aberdeen Proving Grounds, MD. By 1942, the first U.S. Army Bomb Disposal Units were organized and deployed to the European and Pacific Theaters. These companies, however, were deemed to be too immobile to address the workload, so they were further reconsolidated into seven-soldier squads.
After WWII, the U.S. Army contracted, deactivating several bomb disposal units and converting a few to a reserve status. The remaining bomb disposal units were redesignated as "explosive ordnance disposal" in 1949. When the Korean War started in 1950, the U.S. Army faced an urgent need for an EOD capability. Unfortunately, there was a lack of personnel, training, and equipment that require a rapid correction and significant investment. Eventually, once training and equipment requirements were met, EOD squads were grown from seven-soldier to eight-soldier squads.
The Korean War solidified the requirement for a standing U.S. Army EOD capability. The U.S. Army EOD mission was expanded in 1954 to include the mission to render-safe and dispose of nuclear weapons. Then in 1962, the mission was further expanded to include the disposal of chemical and biological munitions. However, those roles and responsibilities would diminish as many are currently shared with other U.S. military services and government agencies.
The Vietnam War further increased demand for U.S. Army EOD Soldiers. The first EOD units were deployed in 1965 and remained through the duration of the war. The Vietnam War was considerably different than previous conflicts. The extraordinary use of munitions and the proliferation of booby traps, later called improvised explosive devices, created new challenges for EOD, requiring units to increase to 12-person detachments and ammunition battalion sections. Despite this increase, there remained a shortage of available EOD personnel. At war's height in 1969, the U.S. had more than 540,000 military personnel in Vietnam, supported by less than 300 EOD personnel. However, despite this example, there was another post-war decline in EOD activity as the mission focused on peacetime emergency response calls.
Throughout the 1980s and 1990s, U.S. Army EOD units continued to provide peacetime support with moments punctuated by international conflict including Operation Desert Storm / Desert Shield, in 1990, the NATO intervention in Bosnia and Herzegovina, in 1995, and the NATO intervention in the Kosovo War, in 1999. These conflicts were the first real test for the reorganized U.S. Army EOD formations. The scale and saturation of UXOs and the massive demolition of ammunition stockpiles challenged the formations and led to lessons learned that helped identify additional training and equipment requirements.
The wars in Afghanistan and Iraq dramatically changed and increased the demand for EOD forces. During the initial invasions, the U.S. Army EOD mission required the focus to be primarily on conventional operations, such as UXO mitigation and emergency ammunition destruction. However, the mission focus quickly transitioned to address the asymmetric threat as counter-insurgency operations (COIN) began. The U.S. invested heavily counter-IED (CIED) capabilities, including EOD. EOD units were expanded and equipped with increasingly sophisticated technologies as adversaries similarly improved their tactics, techniques, and procedures. Mission sets began to transform with increased support to weapons technical intelligence collection and support to special forces operations. However, the increased special operations forces demand came under scrutiny as some were concerned that EOD companies were not being properly trained and equipped to meet the special operations demands. The most significant transformation was to the "modularization" of U.S. Army EOD formations. Starting in 2005, EOD units were realigned with Brigade Combat Teams (BCT), grown from 21-person detachments to 41-person companies, and new headquarters were established. This transformation coincided with a general consolidation of forces aligned with recommendations made by the 2005 Base Realignment and Closure Commission. As part of those recommendations, EOD forces were consolidated onto fewer bases.
U.S. Army EOD downsized as part of the 2013 sequestration, inactivating several battalions headquarters and companies through 2016. In 2017, the U.S. Army adopted multidomain operations as its operational concept for future transformation. The limited scope of counter-insurgency and CIED operations allowed EOD leaders to focus on specific tasks. The challenge for EOD leaders now is to prepare forces for missions across domains and the competition continuum. There are concerns that the U.S. lacks the required EOD force structure to meet all missions. To address those concerns, the TRADOC Proponent Office - Explosive Ordnance Disposal (TPO-EOD) created, and the U.S. Army approved, the largest force design update (FDU) since 2006. The EOD Multidomain FDU (EOD MDO FDU) created new EOD unit types, added created EOD companies, and realigned current EOD units.
Selection and training
Selection
Army Regulation 611-105 Selection, Training, and Suitability for Explosive Ordnance Disposal establishes the minimum requirements for EOD training:
Enlisted candidates apply through a U.S. Army recruiter or retention NCO. Officer candidates are selected during their commissioning source's branching process.
Training
US Army EOD training is completed in two phases:
EOD Phase 1 - US Army preparatory course at Fort Gregg-Adams, Virginia. The course is approximately 7-weeks long and designed to prepare students for Naval School Explosive Ordnance Disposal (NAVSCOLEOD). The training begins with a bomb suit suitability test, then is divided into five phases:
EOD Phase 2 - Naval School Explosive Ordnance Disposal (NAVSCOLEOD) is a joint-service school at Eglin Air Force Base, FL. It is attended by EOD candidates from the US Army, Navy, Air Force, Marines, other government agency representatives, and select international students[8]. The course is 26 academic weeks long and divided into eight phases[7]:
Graduation
Graduates of NAVSCOLEOD will have earned the Explosive Ordnance Disposal Badge. The badge is issued on a temporary status, individuals must remain in good standing for 18-months before the award becomes permanent.
Additional training
Upon completion of EOD Phase 2, EOD Officers will attend a week-long course Platoon Leader's Course to be familiarized with essential duties.
EOD Soldiers may be required to attend various other courses dependent on mission requirements, examples include: airborne, air assault, defensive driving, advanced marksmanship, advanced IED defeat (AIEDDs), and various other civil or joint schools.
Team leader validation
Soldiers who lead an EOD must be validated by their leadership through a process called "Team Leader Validation." Team Leader Validation is a unit-led and administered program designed to ensure leaders have the requisite skills to operate independently. Tasks vary between commands and mission sets, example tasks include: x-ray interpretation, vehicle-borne IED, CBRN incident response, and IED hand entry.
Structure
EOD units often deploy and operate independently from their higher headquarters. Platoons and companies deploy to provide EOD support while battalions and groups provide command and control or augment division, theater, or corps headquarters staff
Units
U.S. Army EOD has active duty and National Guard components. It comprises 3 EOD Groups (Brigade equivalent), 9 Battalions, and 52 Companies.
Active duty
Active duty units are under the United States Army Forces Command (FORSCOM).
20th CBRNE Command subordinates
The 20th CBRNE Command subordinates are as follows.
52nd Ordnance Group (EOD)(Fort Campbell, KY)
Headquarters and Headquarters Detachment (HHD)
184th Ordnance Battalion (EOD) (Fort Campbell, KY)
Headquarters and Headquarters Detachment (HHD)
38th Ordnance Company (EOD) (Fort Stewart, GA)
49th Ordnance Company (EOD) (Fort Campbell, KY)
717th Ordnance Company (EOD) (Fort Campbell, KY)
723th Ordnance Company (EOD) (Fort Campbell, KY)
744th Ordnance Company (EOD) (Fort Campbell, KY)
756th Ordnance Company (EOD) (Fort Stewart, GA)
789th Ordnance Company (EOD) (Fort Moore, GA)
192nd Ordnance Battalion (EOD) (Fort Liberty, NC)
Headquarters and Headquarters Detachment (HHD)
18th Ordnance Company (EOD) (Fort Liberty, NC)
28th Ordnance Company (EOD) (Airborne) (Fort Liberty, NC)
55th Ordnance Company (EOD) (CONUS Support) (Fort Belvoir, MD)
722nd Ordnance Company (EOD) (Fort Liberty, NC)
754th Ordnance Company (EOD) (Fort Drum, NY)
760th Ordnance Company (EOD) (Fort Drum, NY)
767th Ordnance Company (EOD) (Fort Liberty, NC)
71st Ordnance Group (EOD) (Fort Carson, CO)
Headquarters and Headquarters Detachment (HHD) (Fort Carson, CO)
3rd Ordnance Battalion (EOD) (Joint Base Lewis-McChord, WA)
Headquarters and Headquarters Detachment (HHD)
53rd Ordnance Company (EOD) (Yakima Training Center, WA)
707th Ordnance Company (EOD) (Joint Base Lewis-McChord, WA)
734th Ordnance Company (EOD) (Fort Bliss, TX)
741st Ordnance Company (EOD) (Fort Bliss, TX)
759th Ordnance Company (EOD) (Fort Bliss, TX)
787th Ordnance Company (EOD) (Joint Base Lewis-McChord, WA)
79th Ordnance Battalion (EOD) (Fort Riley, KS)
Headquarters and Headquarters Detachment (HHD)
630th Ordnance Company (EOD) (Fort Riley, KS)
774th Ordnance Company (EOD) (Fort Riley, KS)
704th Ordnance Company (EOD) (Fort Cavazos, TX)
752nd Ordnance Company (EOD) (Fort Cavazos, TX)
797th Ordnance Company (EOD) (Fort Cavazos, TX)
242nd Ordnance Battalion (EOD) (Fort Carson, CO)
Headquarters and Headquarters Detachment (HHD)
62nd Ordnance Company (EOD) (Fort Carson, CO)
663rd Ordnance Company (EOD) (Fort Carson, CO)
705th Ordnance Company (EOD) (Fort Johnson, LA)
749th Ordnance Company (EOD) (Fort Carson, CO)
763rd Ordnance Company (EOD) (Fort Leonard Wood, MO)
764th Ordnance Company (EOD) (Fort Carson, CO)
21st Ordnance Company (EOD)(WMD) (Kirtland Air Force Base, NM)
United States Army Indo-Pacific Command (INDOPACOM)
Units in the United States Indo-Pacific Command are as follows.
303rd Ordnance Battalion (EOD) (Schofield Barracks, HI)
Headquarters and Headquarters Detachment (HHD)
65th Ordnance Company (EOD) (Fort Wainwright, AK)
74th Ordnance Company (EOD) (Schofield Barracks, HI)
716th Ordnance Company (EOD) (Joint Base Elmendorf-Richardson (JBER), AK)
Republic of Korea
718th Ordnance Company (EOD) (Camp Humphreys, Republic of Korea)
United States Army European and Africa Command (USAEUR-AF)
Germany
702nd Ordnance Company (EOD) (Grafenwoehr Training Area, Germany)
720th Ordnance Company (EOD) (Baumholder Army Airfield, Germany)
Egypt
Task Force Sinai - EOD Detachment (Sinai, Egypt)
National Guard
48th Ordnance Group (EOD) (AZ) (Arizona Army National Guard) (Phoenix, AZ)
157th Ordnance Battalion (EOD) (Arizona Army National Guard) (Phoenix, AZ)
Headquarters and Headquarters Detachment (HHD)
202nd Ordnance Company (EOD) (Georgia Army National Guard) (Waynesboro, GA)
221st Ordnance Company (EOD) (Florida Army National Guard) (Camp Blanding, FL)
387th Ordnance Company (EOD) (Massachusetts Army National Guard) (Camp Edwards, MA)
430th Ordnance Company (EOD) (North Carolina Army National Guard) (Washington, NC)
745th Ordnance Company (EOD) (Michigan Army National Guard) (Camp Grayling, MI)
753rd Ordnance Company (EOD) (West Virginia Army National Guard) (Camp Dawson, WV)
361st Ordnance Company (EOD) (Arizona Army National Guard) (Phoenix, AZ)
1003rd Ordnance Company (EOD) (Arizona Army National Guard) (Phoenix, AZ)
1600th Ordnance Company (EOD) (Puerto Rico Army National Guard) (Camp Santiago, PR)
501st Ordnance Battalion (EOD) (NY) (New York Army National Guard) (Glenville, NY)
Headquarters and Headquarters Detachment (HHD)
1108th Ordnance Company (EOD) (New York Army National Guard) (Glenville, NY)
741st Ordnance Battalion (EOD) (WA) (Washington Army National Guard) (Bremerton, WA)
Headquarters and Headquarters Detachment (HHD)
217th Ordnance Company (EOD) (California Army National Guard)(Camp Roberts, CA)
319th Ordnance Company (EOD) (Washington Army National Guard) (Pasco, WA)
363rd Ordnance Company (EOD) (Arizona Army National Guard) (Phoenix, AZ)
3665th Ordnance Company (EOD) (Nevada Army National Guard) (Las Vegas, NV)
See also
Explosive Ordnance Disposal - Overview of EOD
Explosive Ordnance Disposal (US Navy) - Sister service EOD Capability
Explosive Ordnance Disposal Badge - Military badge for the United States Armed Forces
20th CBRNE Command - Largest headquarters for US Army EOD
52nd Ordnance Group (EOD) - EOD Group
71st Ordnance Group (EOD) - EOD Group
External links
Official US Army Recruiting Site
Office of the EOD Commandant
20th CBRNE Command
References
Explosive ordnance disposal units and formations
US Army NCO training
Ordnance units and formations of the United States Army
Branches of the United States Army
Military logistics of the United States
Bomb disposal | Explosive ordnance disposal (United States Army) | [
"Chemistry"
] | 3,456 | [
"Explosion protection",
"Bomb disposal"
] |
77,677,481 | https://en.wikipedia.org/wiki/Tecno%20Camon%2030 | Tecno Camon 30, Tecno Camon 30S Pro, Tecno Camon 30 5G, Tecno Camon 30 Pro 5G and Tecno Camon 30 Premier 5G are Android-based smartphones manufactured, released and marketed by Tecno Mobile as part of Tecno Camon 30 series. The devices were unveiled as successors to Tecno Camon 20 series.
The Camon 30 series is an upgraded version of Camon 20 series, coming with different features, including the OS, design and processor. The phones has received generally favorable reviews, with critics mostly noting the IP54 water/dust resistance, design and performance.
Specifications
Hardware
As with the predecessor, all the devices feature an AMOLED display with 1080p support and a display size of 6.67-inches. Both Tecno Camon 30 Pro 5G and Camon 30 Premier 5G feature MediaTek Dimensity 8200. The Tecno Camon 30 5G features MediaTek Dimensity 7020.
Software
The devices ship with Android 14 with HiOS 14 and will receive two major Android updates.
References
Tecno smartphones
Android (operating system) devices
Mobile phones introduced in 2024 | Tecno Camon 30 | [
"Technology"
] | 253 | [
"Mobile technology stubs",
"Mobile phone stubs"
] |
77,678,036 | https://en.wikipedia.org/wiki/Dorothy%20Pile | Dorothy Lilian Pile (26 July 1902 – 1 February 1993) was a British metallurgist, first woman to be admitted to the Institution of Metallurgists and past president of the Women's Engineering Society.
Early life
Dorothy Lilian Pile was born in Yorkshire on 26 July 1902.
Career
In 1920 Pile's first job was as at the Midland Laboratory Guild Ltd. where her father was the chief metallurgist. Her role was in the chemical laboratory as an assistant working on physical testing and metallography before she became more involved in sheet metal research.
In 1949, Pile was appointed as a metallurgist at the Design and Research Centre of the Gold, Silver and Jewellery Trade, in London and later became an industrial liaison officer.
Professional memberships
Pile was the first woman to become a member of the Institution of Metallurgists in 1946. Later in 1983 she also became the first woman to be awarded honorary fellowship. As a thank you she presented the institution with a presidential tankard which is still held by the IOM3 Historical Collection.
Pile was an active member of the Birmingham Metallurgical Association and in 1949 she was elected president. Pile was the first woman to become president of any British metallurgical societies.
Pile became the president of the Women's Engineering Society (WES) in 1954, succeeding Ella Mary Collin in the role. Pile's successor as president was Kathleen Mary Cook. Pile presented WES with a President's Medal on 29th August 1964, featuring the organisation's logo at the time in green enamel.
Pile had various other roles and memberships to industrial societies and would often be the only woman in attendance at society dinners. She is known to have been referred to as the "metallurgical aunt" at such events.
References
1902 births
1993 deaths
British women engineers
Metallurgists
Women's Engineering Society | Dorothy Pile | [
"Chemistry",
"Materials_science"
] | 381 | [
"Metallurgists",
"Metallurgy"
] |
77,678,644 | https://en.wikipedia.org/wiki/Paranoid%20algorithm | In combinatorial game theory, the paranoid algorithm is an algorithm that aims to improve the alpha-beta pruning capabilities of the maxn algorithm by making the player p chosen to maximize the score "paranoid" of the other players by assuming they are cooperating to minimize p's score, thus minimizing any n-player game to a two-player game by making the opposing player the sum of the other player's scores. This returns the game to a zero-sum game and makes it analyzable via any optimization techniques usually applied in pair with the minimax theorem. It performs notably faster than the maxn algorithm because of those optimizations.
See also
Maxn algorithm
Minimax algorithm
References
Game theory
Optimization algorithms and methods | Paranoid algorithm | [
"Mathematics"
] | 153 | [
"Mathematical analysis",
"Mathematical analysis stubs",
"Recreational mathematics",
"Combinatorics",
"Game theory",
"Combinatorial game theory"
] |
77,680,230 | https://en.wikipedia.org/wiki/Weather%20events%20during%20wars | This is a list of weather events which occurred during wars and how those weather events affected the wars.
16th century
Sengoku period
Siege of Katsurayama – The siege in 1557 was fought between the forces of the Japanese daimyō Takeda Shingen and Uesugi Kenshin as part of the Kawanakajima campaigns. Katsurayama castle was a strategically vital Uesugi stronghold in the contested Shinano Province and, when it was isolated from reinforcements due to late snow in early 1557, the Takeda clan used this opportunity to seize it under Baba Nobuharu, shielded from view by heavy snowfall.
Anglo-Spanish War (1585–1604)
Spanish Armada – In 1588, the Spanish Empire created the Spanish Armada and set sail to invade the Kingdom of England. While the Spanish ships were anchored off the coast a France, the British set fire to eight ships, letting the wind and tide help set fire across the fleet. Soon after, the British launched an attack on the Spanish Armada during sea storms. These storms are attributed to the reason the British defeated the Spanish invasion.
17th century
First English Civil War
Battle of Nantwich – In 1643 or 1644, Prince Rupert made an abortive attack on the Parliamentarian stronghold of Aylesbury England. 500 men are reported to have frozen to death on 21 January. On 25 January a sudden thaw caused a bridge to collapse over the River Weaver, splitting Royalist cavalry forces at the Battle of Nantwich resulting in their defeat.
18th century
Great Northern War
Swedish invasion of Russia – In the Great Northern War, Charles XII of Sweden invaded the Russian Empire, crossing the Vistula on 1 January 1708. The Russians retreated, adopting a scorched-earth policy. The winter of 1708–1709 was the most brutal of the 18th century, so severe that the seaport of Venice froze during the Great Frost of 1709. Charles' 35,000 troops were crippled, and by the spring of 1709 only 19,000 were left. The Battle of Poltava in the Ukrainian Cossack Hetmanate in late June 1709 sealed the end of the Swedish Empire.
American Revolutionary War
George Washington's crossing of the Delaware River – On December 25, 1776, George Washington and the Continental Army crossed the icy Delaware River. During the crossing, the weather became progressively worse, turning from drizzle to rain and then to sleet and snow. "It blew a hurricane," one soldier recalled.
Battle of Long Island – During the battle, the British trapped and laid siege to George Washington and the United States' Continental Army with their army and the East River. Instead of directly attacking the Continental Army, the British began digging trenches. On the afternoon of August 28, 1776, rain fell, which concealed the Continental Army cannons, which attacked the British forces. Over the next day, the Continental Army planned on how to evacuate across the East River to escape the British siege. During the night on August 30, a dense fog set across the river, which allowed the entire Continental Army's 9,000 troops to cross the river with no casualties.
Battle of Monmouth Court House – During the battle, most of the casualties occurred from heat-related illnesses.
Battle of Rhode Island – A French naval force under Admiral Charles Henri Hector d'Estaing was sent to assist Washington; deciding New York was too formidable a target, in August they launched a combined attack on Newport, with General John Sullivan commanding land forces. The resulting Battle of Rhode Island was indecisive; badly damaged by a storm, the French withdrew to avoid putting their ships at risk. Further activity was limited to British raids on Chestnut Neck and Little Egg Harbor in October.
19th century
Napoleonic Wars
French invasion of Russia – Napoleon's of 610,000 men invaded Russia, heading through territory of today's Belarus towards Moscow, in the beginning of summer on 24 June 1812. The Russian army retreated before the French and again burnt their crops and villages, denying the enemy their use. Napoleon's army was ultimately reduced to 100,000. His army suffered further, even more disastrous losses on the retreat from Moscow, which started in October. Multiple sources concur that winter and its aftermath was only a contributing factor to Napoleon's defeat and retreat.
War of 1812
Burning of Washington – Following the United Kingdom's capture of Washington, D.C., the capital of the United States, a sudden, very heavy thunderstorm—possibly a hurricane—put out the fires started by the British. It also spun off a tornado that passed through the center of the capital, setting down on Constitution Avenue and lifting two cannons before dropping them several yards away and killing British troops and American civilians alike. Following the storm, the British troops returned to their ships, many of which were badly damaged. There is some debate regarding the effect of this storm on the occupation. While some assert that the storm forced the British to retreat, historians have argued that their intention was only to destroy the city's government buildings, rather than occupy it for an extended period. The British occupation of Washington lasted only about 26 hours. Despite this, the "Storm that saved Washington", as it became known, did the opposite according to some. The rains sizzled and cracked the already charred walls of the White House and ripped away at structures the British had no plans to destroy (such as the Patent Office).
American Civil War
Burnside's Mud March – During the march, the weather deteriorated, with a strong storm producing cold temperatures, strong wind and heavy precipitation.
20th century
World War II
Nazi occupation of Poland – A strong F2 tornado struck the village of Borzymy, killing a farmer who was thrown away. The exact date of the tornado is unknown, but modern meteorologists with the European Severe Storms Laboratory believe it occurred 21 July 1940 in occupied Poland.
Operation Barbarossa – During World War II, the Wehrmacht lacked necessary supplies, such as winter uniforms, due to the many delays in the German army's movements. At the same time, Hitler's plans for the 1941 invasion of the Soviet Union, Operation Barbarossa, actually miscarried before the onset of severe winter weather. Neither Hitler nor the General Staff anticipated a long campaign lasting into the winter. Thus, they failed to make adequate preparations for a possible winter campaign, such as the distribution of warm clothing and winterization of vehicles and lubricants. In fact his eastern army suffered more than 734,000 casualties (about 23% of its average strength of 3,200,000) during the first five months of the invasion before the winter started in recently occupied Poland and Soviet Belarus, Ukraine, and western Russia. On 27 November 1941, Eduard Wagner, the Quartermaster General of the German Army, reported that "We are at the end of our resources in both personnel and material. We are about to be confronted with the dangers of deep winter." Also of note is the fact that the unusually early winter of 1941 cut short the rasputitsa season, improving logistics in early November, with the weather still being only mildly cold.
Battle of the Atlantic / North Atlantic weather war – In October 1943, Nazi Germany established Weather Station Kurt, in Labrador, Dominion of Newfoundland, marking the only known armed German military operation on land in North America during the Second World War. Weather Station Kurt was established by U-537, commanded by Kapitänleutnant Peter Schrewe, who carried WFL-26, codenamed "Kurt", a meteorologist, Dr. Kurt Sommermeyer, and his assistant, Walter Hildebrant. En route, the U-boat was caught in a storm and a large breaker produced significant damage, including leaks in the hull and the loss of the submarine's quadruple anti-aircraft cannon, leaving it both unable to dive and defenceless against Allied aircraft. The weather station functioned for only a few days before its signals became degraded and within three weeks it permanently failed. The U-boat undertook a combat patrol in the area of the Grand Banks of Newfoundland, during which she survived three attacks by Canadian aircraft, but sank no ships.
D-Day – See also: Weather forecasting for Operation Overlord – Eisenhower had tentatively selected 5 June as the date for the assault. However, on 4 June, conditions were unsuitable for a landing: high winds and heavy seas made it impossible to launch landing craft, and low clouds would prevent aircraft from finding their targets. The weather forecast that reported the storms was sent from a weather station on the western coast of Ireland. Group Captain James Stagg of the Royal Air Force (RAF) met Eisenhower on the evening of 4June. He and his meteorological team predicted that the weather would improve enough for the invasion to proceed on 6 June. The next available dates with the required tidal conditions (but without the desirable full moon) would be two weeks later, from 18 to 20 June. Postponement of the invasion would have required recalling men and ships already in position to cross the English Channel and would have increased the chance that the invasion plans would be detected. After much discussion with the other senior commanders, Eisenhower decided that the invasion should go ahead on 6 June. A major storm battered the Normandy coast from 19 to 22 June, which would have made the beach landings impossible. Allied control of the Atlantic meant German meteorologists had less information than the Allies on incoming weather patterns. As the Luftwaffe meteorological centre in Paris was predicting two weeks of stormy weather, many Wehrmacht commanders left their posts to attend war games in Rennes, and men in many units were given leave. Field Marshal Erwin Rommel returned to Germany for his wife's birthday and to petition Hitler for additional Panzer divisions.
Sinking of the SS Oria – The ship was hit by a severe windstorm, which capsized and sank the steamer. At least 4,102 people were killed, which included 4,000 Italian prisoners (43 officers, 118 non-commissioned officers and 3,955 enlisted men), 60 German soldiers to guard the Italian prisoners, and 54 Greeks.
Battle of the Bulge – The Germans achieved a total surprise attack on the morning of 16 December 1944, due to a combination of Allied overconfidence, preoccupation with Allied offensive plans elsewhere and poor aerial reconnaissance due to bad weather. American forces were using this region primarily as a rest area for the U.S. First Army, and the lines were thinly held by fatigued troops and inexperienced replacement units. The Germans also took advantage of heavily overcast weather conditions that grounded the Allies' superior air forces for an extended period. Improved weather conditions from around 24 December permitted air attacks on German forces and supply lines. On 26 December the lead element of Patton's U.S. Third Army reached Bastogne from the south ending the siege.
Atomic bombings of Hiroshima and Nagasaki – Following the atomic bombing of Hiroshima on August 6, 1945, the United States was preparing to drop another atomic bomb on the Empire of Japan. The second atomic bomb, codenamed Fat Man, was set to be dropped on the Japanese town of Kokura. On the morning of August 9, 1945, Major Charles Sweeney was ordered to drop the bomb using only visual targeting and not with any radar capabilities. Due to nearby firebombings, visibility was low over Kokura. After circling the city for 50 minutes, Sweeney abandoned the city and flew to the secondary target of Nagasaki. Coincidentally, Tetsuya Theodore “Ted” Fujita was a resident of and in Kokura the morning of August 9, 1945. Fujita went on as a meteorologist to create the Fujita scale used to rank tornadoes and Fujita studied the damage caused by the nuclear explosions, which contributed to his understanding of downbursts and microbursts as "starbursts" of wind hitting the Earth's surface and spreading out.
21st century
War in Afghanistan (2001–2021)
United States invasion of Afghanistan – In October 2001, just before the United States began their invasion of Afghanistan, three U.S. Air Force meteorologists were secretly deployed into the remote mountains of South Asia, with the tasks of collecting and transmitting weather data. The first weather report from these meteorologists were read by the U.S. commanding officers before the invasion began. Over the course of the invasion and subsequent war, “tens of thousands of weather forecasts” were taken and dispatched by military meteorologists.
On April 6, 2005, a United States CH-47 Chinook helicopter crashed in a sandstorm near Ghazni, killing all aboard (fourteen American soldiers, one marine and three civilian contractors).
2003 invasion of Iraq
Battle of Nasiriyah – By 28 March, a severe sandstorm slowed the coalition advance as the 3rd Infantry Division halted its northward drive halfway between Najaf and Karbala. Air operations by helicopters, poised to bring reinforcements from the 101st Airborne, were blocked for three days. There was particularly heavy fighting in and around the bridge near the town of Kufl.
Russo-Ukrainian War
Russian invasion of Ukraine – During the Russian invasion of Ukraine in 2022, a tornado outbreak affected both Russia and Ukraine.
Russian invasion of Ukraine – During the winter months of the invasion, Russian forces targeted Ukrainian electrical infrastructure, which was widely described as Russia "weaponizing the Ukrainian winter" to degrade civilian morale.
See also
Military meteorology
Cold-weather warfare
References
Weather-related lists
Military meteorology | Weather events during wars | [
"Physics"
] | 2,734 | [
"Weather",
"Physical phenomena",
"Weather-related lists"
] |
77,681,272 | https://en.wikipedia.org/wiki/Corticifraga%20peltigerae | Corticifraga peltigerae is a species of lichenicolous (lichen-dwelling) fungus in the family Gomphillaceae, and the type species of the genus Corticifraga. Its typical host lichen is Peltigera, although on occasion it is found on Solorina and Pseudocyphellaria. The fungus was first described in 1867 by the German botanist Karl Wilhelm Gottlieb Leopold Fuckel, who initially classified it in the genus Peziza. It has been transferred to several genera early in its taxonomic history, before ending up in Corticifraga, which was newly circumscribed by David Leslie Hawksworth and Rolf Santesson in 1990 to contain lichenicolous fungi previously referred to Phragmonaevia.
References
Gomphillaceae
Fungus species
Fungi described in 1867
Lichenicolous fungi
Taxa named by Karl Wilhelm Gottlieb Leopold Fuckel | Corticifraga peltigerae | [
"Biology"
] | 194 | [
"Fungi",
"Fungus species"
] |
77,681,720 | https://en.wikipedia.org/wiki/Red%20List%20of%20the%20Bulgarian%20Vascular%20Plants | List by Bulgarian Academy of Sciences
See here for a comprehensive list of IUCN Red Lists
See here for a comprehensive List of Red Lists by country.
The Red List of Bulgarian Vascular Plants'' is a detailed publication that catalogues the national threat status of 801 species of vascular plants from Bulgaria. This list has been evaluated using Version 3.1 of the IUCN Red List Categories and Criteria.
See also
Geography of Bulgaria
Red Data Book of the Republic of Bulgaria
List of protected areas of Bulgaria
List of mammals of Bulgaria
List of birds of Bulgaria
List of reptiles of Bulgaria
List of amphibians of Bulgaria
References
Ecology literature
Conservation biology
IUCN Red List | Red List of the Bulgarian Vascular Plants | [
"Biology"
] | 128 | [
"Conservation biology"
] |
77,683,517 | https://en.wikipedia.org/wiki/Ammonium%20hexafluorostannate | Ammonium hexafluorostannate is an inorganic chemical compound with the chemical formula .
Physical properties
Ammonium hexafluorostannate typically appears as a white crystalline solid. The compound is soluble in water and insoluble in organic solvents.
Uses
Ammonium hexafluorostannate is a source of tin in various chemical synthesis processes, facilitating production of tin-containing compounds and materials.
References
Fluoro complexes
Stannates
Ammonium compounds
Fluorometallates
Hexafluorides | Ammonium hexafluorostannate | [
"Chemistry"
] | 108 | [
"Ammonium compounds",
"Salts"
] |
77,684,687 | https://en.wikipedia.org/wiki/Ondelopran | Ondelopran (LY-2196044) is an experimental drug being investigated for the treatment of alcoholism.
Mechanism of action
Ondelopran appears to be an antagonist at opioid receptors, which means it blocks the action of other opioids (including endogenous opioids like endorphins) by preventing them from binding to the receptor. It antagonizes the three primary opioid receptors with potency of 0.4 (mu), 0.6 (kappa), and 1.9 nM (delta).
Potential use
A study has shown that treatment with ondelopran reduces the amount of alcohol intake (significantly more than in the placebo group), which means it could be a good path for the treatment of alcoholism. Another test also displays more results which go in the same conclusion.
References
Mu-opioid receptor antagonists
Delta-opioid receptor antagonists
Kappa-opioid receptor antagonists
Experimental drugs
Amides
Pyridines
Phenol ethers
Fluoroarenes
Tetrahydropyrans | Ondelopran | [
"Chemistry"
] | 222 | [
"Amides",
"Functional groups"
] |
77,684,881 | https://en.wikipedia.org/wiki/Sodium%20ferrate | Sodium ferrate is a chemical compound with the formula Na2FeO4. It is a sodium salt of ferric acid that is very difficult to obtain. In most iron compounds, the metal has an oxidation state of +2 or +3. Ferric acid, with an oxidation state of +6, is extremely unstable and does not exist under normal conditions. Therefore, its salts, such as sodium ferrate, also tend to be unstable. Due to its high oxidation state, FeO42- is a potent oxidizing agent.
Synthesis
The synthesis of sodium ferrate(VI) appears to be very delicate due to the instability of ferrate resulting from its high oxidizing power.
The methods to synthesize ferrate(VI) are: thermal, chemical and electrochemical. The thermal method usually requires high temperatures (about 800 °C) and habitually has a low efficiency (50%). The chemical method is multiphase and requires a large number of chemical compounds. The electrochemical method, compared to the other two methods mentioned, has advantages such as the product purity, low solvent demand and the use of an electron which is known as a clean oxidant.
Wet chemistry oxidation
In this methodology, a solution containing Fe(III) is oxidized in the presence of NaOH and converted to Fe(VI)O42-. However, this compound degrades rapidly, so additional steps such as "sequestration", washing and drying processes are necessary to obtain a more stable product.
Another drawback encountered with this methodology is related to the isolation and acquisition of the dry product from the corresponding solution, due to the high solubility of Na2FeO4 in a saturated NaOH solution. By modifying the production procedure in which chlorine gas is passed through a NaOH-saturated solution of trivalent iron, a dry compound containing 41.38% of Na2FeO4 can be obtained.
The wet oxidation method has been extensively used by several researchers to produce solid or liquid ferrate, especially sodium and potassium (VI) ferrate (Na2FeO4 and K2FeO4). Generally, it employs: either ferrous (FeII) or ferric (FeIII) salts as the source of iron ions, calcium, sodium hypochlorite (Ca(ClO)2, NaClO), sodium thiosulfate (Na2S2O3) or chlorine (Cl2) as oxidizing agents and, finally, sodium hydroxide, sodium carbonate (NaOH, NaCO3) or potassium hydroxide (KOH) to increase the pH of the solution.
Electrochemistry
The electrochemical method requires either the use of an anion dissolved in an electrolysis cell containing a strong alkaline solution (NaOH or KOH) or an inert electrode in an Fe(III) solution with an electric current producing the oxidation of iron to Fe(VI). The basic principle is shown in equations 1-4.
Anode reaction:
Fe0(s) + OH−(aq) → FeO42-(aq) + 4H2O(aq) + 6e− (1)
Cathode reaction:
3H2O(aq) → H20(g) + 4H2O(aq) + 6e− (2)
Overall reactions:
Fe0(s) + 2OH−(aq) → FeO42-(aq) + 3H20(g) + 4H2O(aq) (3)
FeO42-(aq) + 2Na+(aq) → Na2FeO4(aq) (4)
The first electrochemical synthesis of ferrate(VI) was carried out around 1841, which is one of the easiest routes to obtain sodium ferrate from solutions without impurities. Later, researchers have performed several experiments in different alkaline environments with various NaOH concentrations, different current densities, temperature, and electrolysis intervals. It was found that increasing temperature could increase the oxidation efficiency, but this behavior is only applicable up to a certain temperature (about 60 °C).
The intensity of the electric current, the material of the anode electrode, and the type and concentration of the electrolyte significantly affect the production of ferrate (VI). Large amounts of carbon in the anode electrode can also increase the efficiency of ferrate (VI) production. Efficiencies above 70% can be achieved using iron or silver electrodes containing 0.9% carbon. The best ferrate (VI) production data have been obtained using a 99.99% pure iron electrode at temperatures around 30 - 60 °C using alternating current (AC).
Dry oxidation
Currently, two methodologies are known for the dry oxidation of sodium ferrate:
The first involves the oxidation of sodium peroxide at 370 °C in the absence of carbon dioxide. The result of this methodology is the production of FeO54- which immediately hydrolyses to FeO42- or into tetrahedral ions in solution with water while adopting a red-violet colour as shown in equation 5.
FeO54-(aq) + 4H2O(aq) → FeO42-(aq) (5)
The second one is based on heating the remains of the galvanized process together with iron oxide in a furnace with a temperature up to 800 °C. The galvanisation residues and iron oxide in combination with sodium peroxide are melted and immediately cooled to produce sodium ferrate (VI), as illustrated in equation 6 below:
Fe2O3(s) + 3Na2O2(s) → 2Na2FeO4(s) + Na2O(s) (6)
Both methods are dangerous and difficult to handle due to the use of high temperatures and therefore the possible risk of explosions.
Properties
The physical properties of this compound can be described as similar to those of potassium ferrate: a dark crystalline solid that dissolves in water to form a reddish-violet solution. However, sodium ferrate has less viscosity than potassium ferrate. It is difficult to isolate in the solid state by traditional crystallisation methods, such as precipitation by heating/cooling, vapor diffusion, antisolvent, etc., due to the ease with which it decomposes.
Regarding its chemical properties, sodium ferrate is a very strong oxidant, stronger and more reactive than potassium ferrate. Its redox potential in acid medium reaches 2.2 V, which is stronger than commonly used compounds for water treatment such as ozone (2.08 V), hydrogen peroxide (1.78 V) or potassium permanganate (1.68 V). In addition, it can also act as a coagulant for unwanted pollution compounds in wastewater, causing them to precipitate as large particles without decomposing into toxic compounds.
Applications
Due to its properties and the fact that it does not generate environmentally toxic by-products, sodium ferrate can be used in the water treatment process. In water treatment it can act as:
Oxidant agent: promoting the oxidation of organic species in metal complexes.
Coagulator: allows removal of inorganic pollution compounds such as heavy metals, inorganic salts, trace elements and metal complexes.
Disinfectant: destroys human pathogens including viruses, spores, bacteria and protozoa.
In addition, sodium ferrate can also remove the colour, odour and oils of polymers and plastics making it a suitable compound for recycling as well as an alternative to traditional processes such as aeration or spreading.
Handling
Sodium ferrate and its decomposition products are non-toxic. However, sodium ferrate in solid state should not be kept in contact with flammable organic compounds.
Sodium ferrate in solid state should be stored in a dark space, without access to air. Ideally, it should be stored in a vacuum or under an inert gas. Its
solutions can be handled under normal conditions, but should be stored cold and not for long periods of time.
References
Ferrates
Sodium compounds
Oxidizing agents | Sodium ferrate | [
"Chemistry"
] | 1,698 | [
"Ferrates",
"Redox",
"Oxidizing agents",
"Salts"
] |
77,685,024 | https://en.wikipedia.org/wiki/VU-0152099 | VU-0152099 is a positive allosteric modulator of the M4 receptor used in scientific research.
Mechanism of action
VU-0152099 is a positive allosteric modulator acting at M4 receptors, it lacks agonist activity, which means it cannot activate the receptor on its own, but can potentiate the activity of M4 receptor agonists such as acetylcholine.
Potential use
In rats, VU-0152099 is able to decrease self-administration of cocaine and reverse hyperlocomotion induced by amphetamine.
These tests show that VU-0152099 could potentially be developed as a treatment for addiction to stimulants.
See also
VU-0152100
References
Amines
Benzodioxoles
Carboxamides
M4 receptor positive allosteric modulators
Thienopyridines | VU-0152099 | [
"Chemistry"
] | 184 | [
"Amines",
"Bases (chemistry)",
"Functional groups"
] |
77,685,882 | https://en.wikipedia.org/wiki/Santa%20Barbara%20Amorphous-15 | SBA-15, an acronym for Santa Barbara Amorphous-15, is a silica-based ordered mesoporous material that was first synthesized by researchers at the university of California Santa Barbra in 1998. This material proved important for scientists in various fields such as material sciences, drug delivery, catalysis, fuel cells and many other due to its desirable properties and ease of production.
Synthesis procedure
The procedure is a typical Liquid-Crystal templating that consists of three steps:
Solution preparation — Pluronic P123 is dissolved in an acidic solution of water at specific molar ratios and the silica precursor typically TEOS or TMOS (sometimes EGMS) is added and mixed in for some time.
Hydrothermal treatment — The solution is sealed in a container and subjected to a temperature T1 for about 24 hours and then a higher temp T2 for 48 hours.
Washing and calcination — The gel obtained from the previous step is washed with water and ethanol under centrifuging, and finally calcinated at about 550 °C for 6 hours.
Structure
The interest in SBA-15 comes from the fact that its mostly mesopoures – meaning the pores are in the range of 2 nm to 50 nm according to the IUPAC definition and the fact that these pores have a well defined structure that is cylindrical shape in hexagonal ordering with their relatively thick pore walls which gives thermal stability.
The sorption isotherms of these materials, demonstrate typical hysteric behavior, which is still under discussion for its causes.
TEM
The transmission electron microscopy of the sample shows the cylindrical pores but also highlights then fact that the pores of this material exhibit geometric deformations.
SAXS
The small-angle X-ray scattering pattern shows typical Bragg peaks to the hexagonal structure of the material. The peak positions, is directly related to the lattice parameter.
where h and k are the miller indices.
References
Materials science
Chemical substances | Santa Barbara Amorphous-15 | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 404 | [
"Applied and interdisciplinary physics",
"Materials science",
"Materials",
"nan",
"Chemical substances",
"Matter"
] |
77,687,680 | https://en.wikipedia.org/wiki/Ammonium%20hexafluoroferrate | Ammonium hexafluoroferrate is an inorganic chemical compound with the chemical formula .
Synthesis
Ammonium hexafluoroferrate can be obtained by reacting ferric fluoride trihydrate and ammonium fluoride in water.
Physical properties
Ammonium hexafluoroferrate is isomorphous with the analogous compounds of aluminum and trivalent titanium, vanadium, and chromium. It crystallizes in a cubic lattice.
The compound's thermal decomposition products are ferrous fluoride and ferric fluoride.
Chemical properties
The compound reacts with xenon difluoride to produce , , Xe, and HF.
Uses
Ammonium hexafluoroferrate is used as a fire retardant.
References
Fluoro complexes
Ferrates
Ammonium compounds
Fluorometallates
Hexafluorides | Ammonium hexafluoroferrate | [
"Chemistry"
] | 187 | [
"Ferrates",
"Ammonium compounds",
"Salts"
] |
77,688,443 | https://en.wikipedia.org/wiki/Monitoring%20of%20geological%20carbon%20dioxide%20storage | Carbon dioxide (CO2) from carbon capture and storage and direct air capture operations is often injected into deep geologic formations. These storage sites can be monitored for CO2 leakage. Monitoring can be done at both the surface and subsurface levels. The dominant monitoring technique is seismic imaging, where vibrations are generated that propagate through the subsurface. The geologic structure can be imaged from the refracted/reflected waves.
Subsurface
Subsurface monitoring can directly and/or indirectly track the reservoir's status. One direct method involves drilling deep enough to collect a sample. This drilling can be expensive due to the rock's physical properties. It also provides data only at a specific location.
One indirect method sends sound or electromagnetic waves into the reservoir which reflects back for interpretation. This approach provides data over a much larger region; although with less precision.
Both direct and indirect monitoring can be done intermittently or continuously.
Seismic
Seismic monitoring is a type of indirect monitoring.
Examples of seismic monitoring of geological sequestration are the Sleipner sequestration project, the Frio CO2 injection test and the CO2CRC Otway Project. Seismic monitoring can confirm the presence of CO2 in a given region and map its lateral distribution, but is not sensitive to the concentration.
Tracer
Organic chemical tracers, using no radioactive or Cadmium components, can be used during the injection phase in a CCS project where CO2 is injected into an existing oil or gas field, either for EOR, pressure support or storage. Tracers and methodologies are compatible with CO2 – and at the same time unique and distinguishable from the CO2 itself or other molecules present in the sub-surface. Using laboratory methodology with an extreme detectability for tracer, regular samples at the producing wells will detect if injected CO2 has migrated from the injection point to the producing well. Therefore, a small tracer amount is sufficient to monitor large scale subsurface flow patterns. For this reason, tracer methodology is well-suited to monitor the state and possible movements of CO2 in CCS projects. Tracers can therefore be an aid in CCS projects by acting as an assurance that CO2 is contained in the desired location sub-surface. In the past, this technology has been used to monitor and study movements in CCS projects in Algeria, the Netherlands and Norway (Snøhvit).
Surface
This provides a measure of the vertical CO2 flux. Eddy covariance towers could potentially detect leaks, after accounting for the natural carbon cycle, such as photosynthesis and plant respiration. An example of eddy covariance techniques is the Shallow Release test. Another similar approach is to use accumulation chambers for spot monitoring. These chambers are sealed to the ground with an inlet and outlet flow stream connected to a gas analyzer. They also measure vertical flux. Monitoring a large site would require a network of chambers.
InSAR
Interferometric synthetic aperture radar (InSAR), is a radar technique used in geodesy and remote sensing.
References
Carbon capture and storage
Environmental monitoring | Monitoring of geological carbon dioxide storage | [
"Engineering"
] | 630 | [
"Geoengineering",
"Carbon capture and storage"
] |
77,691,051 | https://en.wikipedia.org/wiki/Katja%20H%C3%B6ltt%C3%A4-Otto | Katja Hölttä-Otto is a Finnish mechanical engineer and an expert in modular product design. She has worked as an engineering processor in Finland, Singapore, the US, and Australia; she is Professor of Engineering Design at the University of Melbourne.
Education and career
Hölttä-Otto earned a master's degree in mechanical engineering at the Helsinki University of Technology (now part of Aalto University) in 2000, and completed a Ph.D. there in 2005.
While doing her doctoral studies, she was a visiting scholar at the Massachusetts Institute of Technology, in its Center for Innovation in Product Development. Her dissertation, Modular Product Platform Design, was supervised by Kalevi "Eetu" Ekman.
She became an assistant professor at the University of Massachusetts Dartmouth in the US, in 2005. She was an associate professor at the Singapore University of Technology and Design and at Aalto University in Finland before taking her present position as Professor of Engineering Design at the University of Melbourne, in its Department of Mechanical Engineering.
At UMass Dartmouth, she was honored in 2012 by the Center for Women, Gender & Sexuality for her support of women students in engineering. At Aalto University, she became chair of the Professors' Council in 2017.
Recognition
Hölttä-Otto was elected as an ASME Fellow in 2023.
References
External links
Year of birth missing (living people)
Living people
Finnish expatriates in Australia
Finnish engineers
Finnish industrial designers
Finnish women engineers
Mechanical engineers
Women mechanical engineers
Aalto University alumni
University of Massachusetts Dartmouth faculty
Academic staff of Aalto University
Academic staff of the University of Melbourne
Fellows of the American Society of Mechanical Engineers
Finnish expatriates in Singapore
Finnish expatriates in the United States | Katja Hölttä-Otto | [
"Engineering"
] | 343 | [
"Mechanical engineers",
"Mechanical engineering"
] |
77,691,279 | https://en.wikipedia.org/wiki/Veronica%20Milligan | Veronica “Ronnie” Jean Kathleen Milligan (11 March 1926 – 3 September 1989) was an electrical engineer with expertise in construction management and president of the Women's Engineering Society.
Early life and education
Veronica Jean Kathleen O’Neil was born on 11 March 1926 in Pontypridd, South Wales to Jennie K. and Gilbert O'Neil. She attended the Pontypridd Girls' Grammar School. She studied English and Economics at the University College of South Wales and then undertook teacher training. She married Francis Milligan in 1945. Her mother had made her promise not to neglect her career when she married. When her husband and brother began studying for a Higher National Certificate in electrical engineering, Milligan joined them part-time whilst raising her children.
Milligan later completed a diploma in management studies.
Career
When Milligan started a paid graduate traineeship at South Wales Electricity Board she became their first woman in engineering at the company. Milligan stayed at the Board and moved into a supervisory role as maintenance engineer, then later becoming a district planning engineer.
Milligan became a chartered engineer in 1959 with the Institution of Electrical Engineers. She was considered for the position of district manager at the electricity board, but senior management did not feel that a woman should be in charge of professional men, so she decided to leave.
Milligan set up a consultancy in 1961 called Civlec Industrial Advisory Services where she was a management and engineering consultant.
Milligan was appointed as a manpower advisor with the Department of Employment and Productivity, later becoming a headquarters consultant providing expertise on the construction industry.
In 1972, Milligan was appointed to the Gwent Area Health Authority board by the Secretary of State for Wales. She was then re-appointed in 1976. She was also a member of the National Water Council and sat on an industrial tribunals panel.
In 1978, Milligan became a member of the newly created Commission on Energy and the Environment.
Milligan was recorded in Who's Who and was a senior advisor on industry to Monmouth District Council.
Memberships
Milligan joined the Women's Engineering Society (WES) in 1964 and created the Wales and South-Western branch of the society in 1966. She was awarded a bursary by the Caroline Haslett Memorial Trust to attend the First International Conference of Women Engineers and Scientists in 1964. At the third International Conference of Women Engineers and Scientists in 1971, Milligan presented on construction management practices.
Milligan played a significant role in the society, particularly with regards to delivering careers talks to school girls to encourage them into careers in engineering, she did this through her role as Career's Officer. Milligan later became the President of the Women's Engineering Society (WES) in 1978, succeeding Henrietta Bussell in the role. Milligan's successor as president was Maria Watkins.
Milligan also supported careers counselling through her membership and role within the Institute of Electrical Engineers. She was vice chair of the South Wales branch.
She was also an associate member of the British Institute of Management.
Personal Life
Millgan grew up in Pontypridd, South Wales with her father, a school teacher, and brother Maitland O'Neil who was also an electrical engineer. She married Francis Milligan in 1945 and they had two sons. One of the sons, Neil, drowned aged 15 whilst on holiday with his parents in 1964.
Milligan spent her whole life living in South Wales and died in Newport in 1989.
References
1926 births
1989 deaths
People from Pontypridd
British women engineers
Electrical engineers
Women's Engineering Society
Welsh engineers
20th-century Welsh engineers | Veronica Milligan | [
"Engineering"
] | 721 | [
"Electrical engineering",
"Electrical engineers"
] |
77,691,322 | https://en.wikipedia.org/wiki/NGC%203947 | NGC3947 is a barred spiral galaxy in the constellation of Leo. Its velocity with respect to the cosmic microwave background is 6528 ± 23km/s, which corresponds to a Hubble distance of . In addition, three non redshift measurements give a distance of . It was discovered by German-British astronomer William Herschel on 26 April 1785.
Supernovae
Four supernovae have been observed in NGC3947:
SN1972C (type unknown, mag.16) was discovered by Charles Kowal on 18 January 1972.
SN2001P (typeIa, mag.17.5) was discovered by LOTOSS (Lick Observatory and Tenagra Observatory Supernova Searches) on 31 January 2001.
SN2006aa (typeIIn, mag.18.1) was discovered by the Lick Observatory Supernova Survey (LOSS) on 8 February 2006.
SN2013G (typeIa, mag.16) was discovered by the Catalina Sky Survey on 5 January 2013.
NGC 3842 Group
NGC 3947 is part of the 16 member NGC3842 group, named after the brightest galaxy in the group. The other galaxy members are: NGC 3805, NGC 3837, NGC 3842, NGC 3860, NGC 3862, NGC 3883, NGC 3884, NGC 3919, NGC 3929, NGC 3937, NGC 3940, NGC 3954, UGC 6583, UGC 6697, and UGC 6725.
Like many of the neighboring galaxies, NGC3947 and the galaxies in the NGC3842 group are part of the Leo galaxy cluster (also known as Abell1367).
See also
List of NGC objects (3001–4000)
References
External links
3947
037264
+04-28-088
06863
11507+2101
Leo (constellation)
17850426
Discoveries by William Herschel
Barred spiral galaxies
Leo Cluster | NGC 3947 | [
"Astronomy"
] | 402 | [
"Leo (constellation)",
"Constellations"
] |
77,691,352 | https://en.wikipedia.org/wiki/Haworth%20synthesis | The Haworth synthesis is a multistep preparation of alkyl-substituted polycyclic aromatic hydrocarbons developed by the chemist Robert Downs Haworth.
References
Chemical processes | Haworth synthesis | [
"Chemistry"
] | 38 | [
"Chemical process engineering",
"nan",
"Chemical processes",
"Chemical process stubs"
] |
67,553,836 | https://en.wikipedia.org/wiki/Leptocylindrus | Leptocylindrus is a genus of diatoms belonging to the family Leptocylindraceae. They are long, cylindrical diatoms that are made up of multiple cells in a line (described as a chain). These cells have chloroplast to allow it to produce energy through photosynthesis by taking in sunlight and carbon dioxide to create sugars. the cells are attached at the cell walls called valves, the cell wall is slightly concave on one side and convex on the other so that the other cell wall attached will fit together.
Reproduction
Leptocylindrus reproduction is both asexual and (in some species) sexual. For the specific species Leptocylindrus danicus, it goes through sexual reproduction when its cells are between 3 and 8 micrometers in width (cells above this width go through asexual reproduction). It begins with Leptoclindrus cells splitting into two uneven gametangia. The female gametangia are longer and more brightly colored cell than the male gametangia. Then the process of meiosis occurs, where gametes are produced in the gametangia, the male gametangium (also known as the spermatogonangium) burst to release quadriflagellate spermia, which divide into biflagellate sperma and again into unflagellate sperm (or just sperm), this process takes about twelve hours to complete. After meiosis the female gametangium (or egg) bends at an angle so that the sperm can attach and enter the egg. the site of entry by the sperm starts to swell as the cytoplasm is sent to the area. after fertilization the auxospore forms at this site, the cytoplasm then contracts and valves (distinct halves of the cell wall) form to create the resting spore. these resting spores finally separate from the parent cell and can remain dormant for long periods because of their thick walls. The whole process in total takes about 36 hours to complete. The resting spores under good conditions well then germinate and then well shed there old valves to form a chain with a maximum width of 14 micrometers, and will reproduce asexually until it is between a width of 3 to 8 micrometer where the process begins again.
When Leptocylindrus danicus, and another species Leptocylindrus aporus (which can't reproduce sexually), goes through asexual reproduction by separating to form two distinct halves of different sizes. After sexual and asexual reproduction, the cell wall is soft and halves individually reconstruct themselves. The soft cell wall expands as it matures and eventually forms a silica shell.
The reproduction rate for Leptocylindrus slows or is halted when conditions are unfavorable. these unfavorable conditions include a depleted environment of the elements silicon and nitrogen, and an environment that is above 16 degrees Celsius and below 10 degrees (sexual reproduction seldom happening above 20 degrees). Therefore Leptocylindrus will usually be found reproducing in a nitric rich warm body of water.
Habitat
Leptoclindrus are widely found in many coastal and shelf waters around the world with the exception of extreme polar climates, as species can't survive below 5 degrees Celsius. They are most abundant seasonally in late spring and summer in European seas to the north (abundant in fjords of Norway in summer months), and autumn (and sometimes in parts of spring) around the southern china sea. Leptocylindrus also prefer nitric rich environment because it allows for favorable conditions for sexual reproduction.
The genus Leptocylindrus is one of the most numerically dominant diatoms in the ocean and is a major component of the spring bloom period in southeastern Australia. Leptocylindrus also differ in make up depending on the habitat and environment; for example, it has been observed that there is significant dissimilarity in the composition of the Leptocylindrus microbiome (at the Operational Taxonomic Unit level (OTU)) between Leptocylindrus strains from differing locations along the east coast of Australia, with a higher diversity and more unique OTUs associated with Leptocylindrus strains isolated from the more northern locations compared to those from the south. Different regions harbor distinct bacterial communities.
Transposable Elements (TE)
Transposable Element (TE, transposon, or jumping gene) is a DNA sequence that can change its position within a genome, sometimes creating or reversing mutations and altering the cell's genetic identity and genome size. Transposition often results in duplication of the same genetic material. TE-related sequences appear to play a role in the adaptation to cold conditions with regard to leptocylindrus, but they may get quieted when the cells remain for a long period in the same environmental conditions. Leptocylindrus play an important role of TEs in the generation of the phenotypic plasticity that can lead to genetic diversity and ultimately to the success of diatoms under different and variable environmental conditions.
Symbiosis of Solenicola-Leptocylindrus
Symbiosis is a term describing any relationship or interaction between two dissimilar organisms. The specific kind of symbiosis depends on whether either or both organisms benefit from the relationship.
The consortium of Solenicola-Leptocylindrus is widespread from polar to equatorial zones, from coastal to oceanic water, and often reaches high abundance.
The most accepted view is that Solenicola is a highly adapted epizoic or parasitic organism; other speculations are that Solenicola is a stage of the diatom life cycle.
The diatom is a widespread species in the world ocean and several studies have investigated its morphology using scanning electron microscopy. The frustule possesses an unusual double-layered structure. Transmission electron microscopy revealed that the frustule was nearly empty and that the protoplasm with mitochondria occupied a very small part of the cell. However, it is uncertain whether the mitochondria belonged to Solenicola or the diatom.
The parasitism requires the occurrence of a free-living host to be colonized or infected by Solenicola. However, there is no evidence of living individuals of Leptocylindrus mediterraneus. A mutualistic symbiosis requires a benefit for the diatom, but apparently Leptocylindrus mediterraneus is not alive when colonized by Solenicola. Therefore, there is weak symbiosis and can be concluded that the molecular phylogeny that Leptocylindrus mediterraneus should no longer belong to the genus.
Species
Species:
Leptocylindrus adriaticus
Leptocylindrus aporus
Leptocylindrus belgicus
Leptocylindrus convexus
Leptocylindrus curvatulus
Leptocylindrus curvatus
Leptocylindrus danicus
Leptocylindrus hargravesii
Leptocylindrus mediterraneus
Leptocylindrus minimus
References
Nanjappa, Deepak, Sanges, Remo, Ferrante, Maria I, and Zingone, Adriana. "Diatom Flagellar Genes and Their Expression during Sexual Reproduction in Leptocylindrus Danicus." BMC Genomics 18.1 (2017): 8
Ajani, Penelope A, Kahlke, Tim, Siboni, Nachshon, Carney, Rick, Murray, Shauna A, and Seymour, Justin R. "The Microbiome of the Cosmopolitan Diatom Leptocylindrus Reveals Significant Spatial and Temporal Variability." Frontiers in Microbiology 9 (2018): 2758. Web.
Pargana, Aikaterini, Musacchia, Francesco, Sanges, Remo, Russo, Monia Teresa, Ferrante, Maria Immacolata, Bowler, Chris, and Zingone, Adriana. "Intraspecific Diversity in the Cold Stress Response of Transposable Elements in the Diatom Leptocylindrus Aporus." Genes 11.1 (2019): 9. Web.
Shikata, Tomoyuki, Iseki, Mineo, Matsunaga, Shigeru, Higashi, Sho‐ichi, Kamei, Yasuhiro, and Watanabe, Masakatsu. "Blue and Red Light‐Induced Germination of Resting Spores in the Red‐Tide Diatom Leptocylindrus Danicus." Photochemistry and Photobiology 87.3 (2011): 590–97. Web.
Buck, K R, and Bentham, W N. "A Novel Symbiosis between a Cyanobacterium, Synechococcus Sp., an Apladistic Protist, Solenicola Setigera, and a Diatom, Leptocylindrus Mediterraneus, in the Open Ocean." Marine Biology 132.3 (1998): 349. Web.
Padmakumar, K B, Cicily, Lathika, Shaji, Anu, Maneesh, T P, and Sanjeevan, V N. "Symbiosis between the Stramenopile Protist Solenicola Setigera and the Diatom Leptocylindrus Mediterraneus in the North Eastern Arabian Sea." Symbiosis (Philadelphia, Pa.) 56.2 (2012): 97–101. Web.
Nanjappa, Deepak, Kooistra, Wiebe H. C. F, Zingone, Adriana, and Valentin, K. "A Reappraisal of the Genus Leptocylindrus (Bacillariophyta), with the Addition of Three Species and the Erection of Tenuicylindrus Gen. Nov." Journal of Phycology 49.5 (2013): 917–36. Web.
French, Fred W, and Hargraves, Paul E. "SPORE FORMATION IN THE LIFE CYCLES OF THE DIATOMS CHAETOCEROS DIADEMA AND LEPTOCYLINDRUS DANICUS1." Journal of Phycology
Diatoms
Diatom genera | Leptocylindrus | [
"Biology"
] | 2,157 | [
"Diatoms",
"Algae"
] |
67,554,094 | https://en.wikipedia.org/wiki/Topochemical%20polymerization | Topochemical polymerization is a polymerization method performed by monomers aligned in the crystal state. In this process, the monomers are crystallised and polymerised under external stimuli such as heat, light, or pressure. Compared to traditional polymerisation, the movement of monomers was confined by the crystal lattice in topochemical polymerisation, giving rise to polymers with high crystallinity, tacticity, and purity. Topochemical polymerisation can also be used to synthesise unique polymers such as polydiacetylene that are otherwise hard to prepare.
Various reactions have been adopted in the field of topochemical polymerisation, such as [2+2], [4+2], [4+4], and [3+2] cycloaddition, linear addition between dienes, trienes, diacetylenes. Other than linear polymers, they can also be applied to the synthesis of two dimensional covalent networks.
History
The term "topochemistry" was first introduced by Kohlschütter in 1919, referring to the chemical reactions driven by the molecular alignments within the crystal. The prefix "topo" came from the Greek word "topos", which means "site". These reactions quickly draw people's attention because of their high conversion as well as solvent/catalyst-free nature. However, the early studies were usually serendipitous.
In the 1960s, Schmidt's work on [2+2] photodimerization of cinnamic acids established the systematic approach to study the topochemical reactions. They proposed that only double bonds adopting coplanar and parallel orientation within a distance of 3.5-4.2 Å could react with each other in the crystal lattice. This empirical rule was later referred to as Schmidt's criteria.
[2+2] cycle addition and diacetylene polymerization are among the early examples of topochemical polymerization. As shown in the figure, the formation of 1,3-diphenyl substituted cyclobutane derivatives was first studied in detail by Hasegawa and his coworkers in 1967. A series of similar monomers had also been studied by them. In 1969, the 1,4-addition polymerization of diacetylene was confirmed by Wegner and his coworkers. Restricted by the experimental condition, early researchers of topochemical polymerization usually characterized the reaction process and product with traditional chemical methods. The development of modern analysis technology such as single-crystal X-ray diffraction greatly facilitated the systematic study of topochemical polymerization and kept the popularity till these days.
Design of the Reaction system
Lattice Criteria of Polymerization
In topochemical polymerization, little room is provided for the monomer to adjust their position. Thus, the reacting sites of the monomer should be pre-packed in a suitable manner. If [2+2] cycloaddition is involved in the polymerization, then the alignment of double bonds within the crystal should fulfill the aforementioned Schmidt's criteria. Sometimes multiple parameters should be considered. As shown in the figure, for example, the 1,4-polymerization of diacetylene requires the fine adjustment of angle as well as the monomer packing distance to achieve a satisfying reaction site distance dCC (distance between C1 and C4).
The method invented by Schmidt is still the most promising way to investigate the structural criteria of polymerization. In this approach, a series of monomers with different substituents are crystallized and characterized by single-crystal X-ray diffractometer. By comparing their polymerization reactivity and slightly different structure, the suitable range of lattice parameters can be derived.
Though Schmidt's criteria are generally useful for predicting the topochemical reactivity, there are many instances of violation of these criteria. Many examples of smooth reaction of crystals that are not expected to be reactive based on Schmidt's criteria are reported.
Strategies of Lattice Control
Various methods have been proposed to achieve the suitable alignment of monomers in the crystal. These methods can be divided into two categories:
An obvious method is to introduce supramolecular interactions to the monomer. Popular choices include π - π stacking interactions, hydrogen/halogen bonding interactions, and Coulomb interactions. These interactions are sometimes inherent properties of reaction groups, such as π-π interaction between azide and acetylene group, or stacking force between biphenylethylene unit. Sometimes the side groups are introduced to form a network within the crystal.
The other strategy is to take advantage of the so-called "host-guest" assembly. In this case, the monomer is designed to link to a "host" molecule, while the host molecule is in charge of forming the ordered network. The host molecule stays intact during the polymerization. Such strategies simplify the synthesis of monomer.
The Stress of Polymerization
Although the movement of the mass center of the monomer is restricted by the crystal during the polymerization, the slight change of the bond length before and after the reaction give rise to the shifting of lattice parameters. Consider a real-life topochemical polymerization initiated by irradiation: if monomer beneath the surface polymerizes later due to the light absorption near the surface, the already polymerized layer will shrink or expand, causing unbalanced stress within the crystal. The crystal might break or even lose crystallinity if the stress isn't handled properly.
Using elastic interaction such as weak hydrogen bonds is a common strategy to release the stress. It has been found that the bond length of the hydrogen bond in the crystal would change after polymerization, acting as cushion. Another possible routine is to introduce "soft" parts (C-C or C-O bond free to rotate instead of rigid conjugated system) in the monomer molecule. But it will in turn increase the difficulty of crystallization.
Reaction condition
Light Irradiation
Light irradiation can initiate the reaction while avoiding exerting additional physical effects on the monomer crystal. It can be used in topochemical polymerization based on free radical mechanism such as 1,4-polymerization of diacetylene or diene polymerization. UV light is widely used as initiation method as it does in conventional polymerization. In some circumstances, however, the polymerization initiated by UV light is so slow that unbalanced pressure will accumulate more easily as previously stated. γ-irradiation can trigger the reaction faster due to the shorter wavelength. Thus, it was proved to be a better choice than UV in various reactions such as topochemical polymerization of 1,3-diene carboxylic acid derivatives.
Heat
Heat can be used to trigger the electrocyclization topochemical polymerization. For example, Kana M. Sureshan et al. have developed a series of bio-compatible polymer crystals based on [3+2] Topochemical Azide-Alkyne Cycloaddition (TAAC) reaction and [3+2] topochemical ene-azide cycloaddition (TEAC) reaction. The monomers are polymerized by heating for a few days. Contrary to the light-initiated topochemical polymerization, the lower temperature and slower reaction rate would produce high quality polymer crystals. This is due to the fact that heat expansion is not obvious in lower temperature.
Pressure
Topochemical polymerization can also be triggered by pressure. It has been reported that the cocrystal of diododiacetylene (guest) and bispyridyl oxalamide (host) could be polymerized under pressure. Interestingly, no polymerization was observed under light or heat due to the unfavorable distance between diacetylene units. The researcher postulated that the high pressure might "squeeze" the reactive site together and initiate the polymerization.
Application
Tacticity/Stereochemistry Control
Tactic and stereoselective polymerizations are traditionally catalyzed by metal-organic complexes. Topochemical polymerization provides an additional choice. In addition, by changing the alignment of the monomer within the crystal, the tacticity/stereochemistry of the polymer product could be easily controlled. An intuitive example is shown in the figure. In topochemical polymerization of 1,3-diene carboxylic acid derivatives, polymers with four different configurations can be prepared. Their structural relationships with the monomer packing are also shown in the figure.
Single Crystal Polymer
Single crystal polymers have unique applications in various fields Compared to single crystals of small molecules. Because of the long chain and various conformation, it is hard for the polymers to be crystallized directly from solution. Few examples of polymer single crystals prepared in this way suffered from low quality and small size. Topochemical polymerization provides a potential solution to yield high-quality polymer single crystals.
If the polymer is still mono crystalline, the transformation from single-crystal monomer to polymer is called single-crystal-to-single-crystal (SCSC) transformation, which required a more sophisticated design than normal topochemical polymerization. In order to prevent the polymer from breaking into polycrystalline powder, the stress-releasing strategies should be carefully considered. However, the study on general criteria of SCSC transition is still in its infancy and requires further study.
Coordination Polymer
In addition to organic polymers, coordination polymers can also be prepared with topochemical polymerization. The various conformations of metal-organic complexes provide large libraries of monomer geometry. In addition, the length and angle of metal-ligand bonds are relatively flexible so that stress generated by polymerization is able to be released.
2-D polymers
The Two-dimensional (2-D) polymers formed by topochemical polymerization are popular topics in material chemistry. By synthesizing and polymerizing monomers with functionality greater than 2, the 2-D networks instead of linear polymers can be obtained. [4+4] and [4+2] involving anthracene units are popular choices for 2D-polymer synthesis. 2-D covalent networks with high crystallinity can be produced in this way in high conversion. Recently, schluter et al. synthesized a 2D polymer via 2+2 topochemical cycloaddition reaction.
References
Polymerization reactions
Polymers
Polymer chemistry | Topochemical polymerization | [
"Chemistry",
"Materials_science",
"Engineering"
] | 2,141 | [
"Polymers",
"Polymerization reactions",
"Polymer chemistry",
"Materials science"
] |
67,554,269 | https://en.wikipedia.org/wiki/Hypomyces%20orthosporus | Hypomyces orthosporus is a species of fungus belonging to the family Hypocreaceae.
It is native to Europe and Northern America.
References
Hypocreaceae
Fungus species | Hypomyces orthosporus | [
"Biology"
] | 43 | [
"Fungi",
"Fungus species"
] |
67,554,277 | https://en.wikipedia.org/wiki/Rectangular%20lattice | The rectangular lattice and rhombic lattice (or centered rectangular lattice) constitute two of the five two-dimensional Bravais lattice types. The symmetry categories of these lattices are wallpaper groups pmm and cmm respectively. The conventional translation vectors of the rectangular lattices form an angle of 90° and are of unequal lengths.
Bravais lattices
There are two rectangular Bravais lattices: primitive rectangular and centered rectangular (also rhombic).
The primitive rectangular lattice can also be described by a centered rhombic unit cell, while the centered rectangular lattice can also be described by a primitive rhombic unit cell. Note that the length in the lower row is not the same as in the upper row. For the first column above, of the second row equals of the first row, and for the second column it equals .
Crystal classes
The rectangular lattice class names, Schönflies notation, Hermann-Mauguin notation, orbifold notation, Coxeter notation, and wallpaper groups are listed in the table below.
References
Lattice points
Crystal systems | Rectangular lattice | [
"Chemistry",
"Materials_science",
"Mathematics"
] | 219 | [
"Materials science stubs",
"Lattice points",
"Crystal systems",
"Crystallography stubs",
"Crystallography",
"Number theory"
] |
67,554,287 | https://en.wikipedia.org/wiki/Oblique%20lattice | The oblique lattice is one of the five two-dimensional Bravais lattice types. The symmetry category of the lattice is wallpaper group p2. The primitive translation vectors of the oblique lattice form an angle other than 90° and are of unequal lengths.
Crystal classes
The oblique lattice class names, Schönflies notation, Hermann-Mauguin notation, orbifold notation, Coxeter notation, and wallpaper groups are listed in the table below.
References
Lattice points
Crystal systems | Oblique lattice | [
"Chemistry",
"Materials_science",
"Mathematics"
] | 99 | [
"Materials science stubs",
"Lattice points",
"Crystal systems",
"Crystallography stubs",
"Crystallography",
"Number theory"
] |
67,554,304 | https://en.wikipedia.org/wiki/IEC%2063382 | IEC 63382 is an international standard defining a protocol for the management of distributed energy storage systems based on electric vehicles, which is currently under development. IEC 63382 is one of the International Electrotechnical Commission's group of standards for electric road vehicles and electric industrial trucks, and is the responsibility of Joint Working Group 15 (JWG15) of IEC Technical Committee 69 (TC69).
Standard documents
IEC 63382 consists of the following parts, detailed in separate IEC 63382 standard documents:
IEC 63382-1: Definitions, requirements and use cases
IEC 63382-2: Data models, protocols and messages
IEC 63382-3: Conformance tests
See also
Vehicle-to-grid
ISO 15118
IEC 61850
IEC 61851
IEC 63110
OCPP
References
Electric vehicles
63382 | IEC 63382 | [
"Technology"
] | 173 | [
"Computer standards",
"IEC standards"
] |
67,555,055 | https://en.wikipedia.org/wiki/Focal%20molography | Focal molography (“molography” in short) is a biophysical method for robust and sensitive detection of biomolecular interactions in a label-free manner. The new method enables biomolecular interaction analysis in complex biological samples without the use of additional fluorescent labels. Molography widens the analytic scope of biomolecular interaction analysis techniques in a broad range of applications, e.g. label-free trace analysis of a targeted molecule (called biomarker) in complex samples, such as blood sera, bioreactor fluid or cell culture media. Contrary to refractometric methods for label-free biomolecular interaction analysis, such as surface plasmon resonance (SPR) and reflectometric interference spectroscopy (RIfS), molography allows quantification of molecular interactions in living cells in real time.
Principle
The working principle of molography is illustrated in Figure 1. Molography is based on diffraction of laser light at a special 2D nanopattern of molecular binding sites on the surface of a sensor chip, termed mologram. A mologram is a coherent assembly of binding sites on a chip that form the blueprint of molecular hologram. The hologram has the shape of a focusing diffractive lens and is illuminated by an evanescent wave. Evanescent waves occur when light is totally internally reflected at an interface of two dielectrics. Biomolecules that bind to the mologram diffract laser light into a diffraction-limited focal spot in three dimensional space, the focal point of the mologram. The intensity of the focused light correlates quadratically with the amount of bound molecules on the mologram and therefore also the number of biomolecular interactions that take place.
In complex biological samples, the concentration of off-target molecules is usually significantly higher than the target molecules. Therefore, even in the absence of recognition elements the off-target molecules readily adsorb to the surface of the sensor. However, this a random process and the off-target molecules do not bind to the ordered binding sites of the mologram. Thus, scattering of off-target molecules is uniform in all spatial directions and therefore off-target molecules hardly contribute to the measured light intensity in the narrow solid angle of the focal spot. In essence, focal molography forms a high-frequency spatial affinity lock-in that only measures the Fourier component of the refractive index distribution that corresponds to the binding modulation of the mologram. Since the environmental noise (temperature gradients, buffer changes and nonspecific binding of off-target molecules) is inversely proportional to the spatial frequency and therefore situated mostly at "long" spatial periods most of the noise can be rejected. This property makes molography extremely robust and renders temperature stabilization or sensor equilibration obsolete.
History
Christof Fattinger at Hoffmann-La-Roche in Basel already conceived the physical principles of focal molography in the 1990s when he investigated the bidiffractive grating-coupler. Yet it only emerged in a scientific collaboration between ETH Zürich and the Roche Innovation Center Basel in Switzerland from 2014 to 2020.
Realization: A special photolithographic method enables the synthesis molograms
The synthesis of molograms on the sensor chip is realized with properly designed surface chemistry and reactive immersion lithography (RIL). Through the RIL process the biomolecular recognition structure of the mologram on a light-sensitive non-fouling graft copolymer layer can be created by standard lithography techniques. The copolymer layer is functionalized with photocleavable protection groups that upon illumination create reactive amines. Subsequent surface chemistry steps enable an easy tailoring of recognition molecules specific to the desired analytical application.
Applications of the molography method
The robustness of focal molography against environmental noise gives the method a platform character that enables many possible applications. They range from the investigation of a specific biomolecular interaction in basic biological research to the diagnosis of a critical health condition in an emergency.
The biological applications of molography categorize into five basic classes:
Classical biomolecular interaction analysis (BIA), i.e. the measurement of on-rates, off-rates and binding constants as demonstrated in,
Quantification of biomarkers in biological samples,
Profiling of low-affinity binders on mologram arrays,
Quantification of molecular interactions in living cells in real time, and
Discovery of unknown biomolecular interactions by means of binding assays.
References
Electromagnetism
Nanotechnology
Biochemistry methods
Biophysics
Protein–protein interaction assays
Optical phenomena
Molecular biology techniques
Optical metrology | Focal molography | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering",
"Biology"
] | 968 | [
"Biochemistry methods",
"Physical phenomena",
"Electromagnetism",
"Applied and interdisciplinary physics",
"Protein–protein interaction assays",
"Materials science",
"Optical phenomena",
"Molecular biology techniques",
"Biophysics",
"Fundamental interactions",
"Molecular biology",
"Biochemistr... |
67,556,609 | https://en.wikipedia.org/wiki/NA64%20experiment | NA64 experiment is one of the several experiments at CERN's Super Proton Synchrotron (SPS) particle collider searching for dark sector particles. It is a fixed target experiment in which an electron beam of energy between 100-150 GeV, strikes fixed atomic nuclei. The primary goal of NA64 is to find unknown and hypothetical particles such as dark photons, axions, and axion-like particles.
Secondarily this experiment will also use the muon beams from the SPS with the goal of finding particles that mainly interact with muons and hence could give valuable insights into muon's anomalous magnetic moment. Few other goals of NA64 include searching for invisible neutral kaon decays and meson decays, as well as the hunt of particles that could consist the mirror-type dark matter.
References
External links
NA64 sets bounds on how much new X bosons could change the electron's magnetism
https://na64.web.cern.ch/node/10
NA64 explores gap in searches for axions and axion-like particles
NA64 casts light on dark photons
The plot thickens for a hypothetical "X17” particles
CERN experiments
CERN
Physics experiments
Fixed-target experiments | NA64 experiment | [
"Physics"
] | 258 | [
"Particle physics stubs",
"Physics experiments",
"Experimental physics",
"Particle physics"
] |
67,558,077 | https://en.wikipedia.org/wiki/Peter%20Saulson | Peter Reed Saulson (born October 30, 1954) is an American physicist and professor at Syracuse University. He is best known as a former spokesperson for the LIGO collaboration serving from 2003 to 2007 and research on gravitational wave detectors.
Education
Saulson was born October 30, 1954, in Baltimore, Maryland, into a Jewish family. studied physics at Harvard University where he earned a bachelor's degree (magna cum laude) in 1976. He later studied at Princeton University where he received a master's degree in 1978 and a doctorate in 1981. He was then a post-doctoral scholar at the Massachusetts Institute of Technology, where he started in 1985 and worked as principal research scientist until 1989. In 1989 he was a visiting scientist at the Joint Institute for Laboratory Astrophysics in Boulder, Colorado.
Career
Saulson is Martin A. Pomerantz '37 Professor of Physics at Syracuse University where he co-leads the Gravitational-Wave Astronomy Group. He was associate professor there from 1991 to 1999 and head of the physics department from 2010 to 2013. In 2000-01, he was a visiting professor at Louisiana State University and in 2000 Interferometer Commissioning Leader at LIGO and Caltech.
Saulson was the first elected speaker of the LIGO Scientific Collaboration, succeeding LIGO co-founder Rainer Weiss.
Awards
Saulson was named a fellow of the American Physical Society in 2003 for "his contributions to experimental gravitational physics including pioneering studies of thermal mechanisms affecting interferometer performance and for his educational contributions including authoring one of the most influential books in the field." He was named Syracuse University's 2003-04 University Scholar/Teacher of the Year.
In 2016 he received the National Academy of Sciences Award for Scientific Discovery with Gabriela González, his former PhD student, and David Reitze.
Works
References
External links
1954 births
Living people
American astrophysicists
Syracuse University faculty
Louisiana State University faculty
Harvard University alumni
Princeton University alumni
Massachusetts Institute of Technology alumni
Gravitational-wave astronomy
Fellows of the American Physical Society
20th-century American physicists
Members of the United States National Academy of Sciences
Scientists from Baltimore
American male non-fiction writers | Peter Saulson | [
"Physics",
"Astronomy"
] | 426 | [
"Astronomical sub-disciplines",
"Gravitational-wave astronomy",
"Astrophysics"
] |
67,558,499 | https://en.wikipedia.org/wiki/Bovhyaluronidase%20azoximer | Bovhyaluronidase azoximer, sold under the brand name Longidaze, is a conjugate of proteolytic enzyme hyaluronidase with high- molecular weight copolymer that forms a component of combination therapy regimens for treatment and prevention of diseases associated with connective tissue hyperplasia.
The most frequently observed adverse reactions seen with bovhyaluronidase azoximer include pain at site of injection and injection site reactions such as skin redness, itching and oedema. Local reactions typically resolve themselves in 48–72 hours.
Clinical data
Type: Hyaluronidases
Other names: hyaluronidase conjugate with co-polymer of N-oxide 1,4-ethylenepiperazine and (N-carboxymethyl)-1,4- ethylenepiperazine bromide
Pharmaceutical form: suppositories
Pharmacotheapeutic group: enzymes
ATC Code: V03AX
Medical uses
Bovhyaluronidase azoximer is a porous white or white with a yellowish or brownish tint mass and prepared in ampules 1500 IU or 3000 IE with mannitol excipient (up to 15 mg [for 1500 IE dos] or up to 20 mg (for 3000 IE dose).
The active ingredient belongs to the hyaluronidases family of enzymes that catalyse the degradation of hyaluronic acid. By catalyzing the hydrolysis of hyaluronan, a constituent of the body's extracellular matrix (ECM), hyaluronidase lowers the viscosity of hyaluronan, thereby increasing tissue permeability... It is, therefore, often used in medicine in conjunction with other drugs to speed their dispersion and delivery. It also increases the absorption rate of parenteral fluids given by hypodermoclysis, and is an adjunct in subcutaneous urography for improving resorption of radiopaque agents. Hyaluronidases are also used for extravasation of hyperosmolar solutions.
Approved applications include:
Gynaecology: treatment and prevention of adhesive process in lesser pelvis during inflammatory diseases of internal genital organs, including tubo-peritoneal infertility, intrauterine synechiae, chronic endometritis.
Urology: treatment of chronic prostatitis, interstitial cystitis.
Pulmonology and phthisiology: treatment of pneumosclerosis,
fibrosing alveolitis, and tuberculosis (fibro-cavity, infiltrative, tuberculoma).
Orthopaedics: treatment of joint contracture, arthrosis, Marie-Striinipell disease, haematomas.
History
Medicines incorporating hyaluronidase have been used in medical applications for over 60 years. The US Food and Drug Administration has approved hyaluronidase for the following indications: (1) subcutaneous fluid infusion (hypodermoclysis), (2) as an adjuvant to accelerate the absorption and dispersion of drugs in subcutaneous tissue or to manage extravasation, and (3) as an adjunct to promote the absorption of contrast media in urinary tract angiography (subcutaneous urography). They have also been approved and used for the purpose of increasing hematoma absorption in Europe. Hyaluronidase has a variety of uses in addition to its approved indications. Its current off-label uses include dissolving hyaluronic acid fillers, treating granulomatous foreign body reactions, and treating skin necrosis associated with filler injections.
Recognised limitations for hyaluronidase-based medicines include allergenic properties, presence of ballast impurities, loss of enzymatic activity due to temperature and inhibitors of blood serum. Since administration is via a parenteral route of administration, the enzyme is inactivated by blood serum inhibitors, which shortens its half-life.
Conjugation (covalent binding) of hyaluronidase with polymeric carriers prevents the unfolding of enzyme globule Hyal, increasing resistance to denaturation and the action of inhibitors while preserving the enzymes native structure and activity, thus prolonging its activity. The water-soluble copolymer 1,4-ethylene-piperazine N-oxide and (N-carboxymethyl)-1,4-ethylene-piperazinium bromide, itself an immunomodulator with anti-inflammatory properties, was found to confer increased stability. A comparative study of the stability of commercial hyaluronidase (Lydase®) and bovhyaluronidase azoximer showed a 20-fold increase in length of activity at 37 °C (24 hours vs. 20 days, respectively).
Safety and tolerability
Frequently observed adverse events include (≥ 1/100 to < 1/10) – pain at injection site. Less frequent adverse events (≥ 1/1,000 to < 1/100) include injection site reaction such as skin redness, itching and oedema. All local reactions resolve themselves in 48 – 72 hours. Very rare (< 1/10000) – allergic reactions.
Use of bovhyaluronidase azoximer is contraindicated in known cases of hypersensitivity to hyaluronidase, acute infectious diseases, pulmonary haemorrhage and haemoptysis, recent vitreous haemorrhage, malignant neoplasms, acute renal failure, age under 18 years (no clinical study data available). It should also be used with caution in cases of chronic liver failure (administer not more than once per week) and is contraindicated for use in pregnant and breast-feeding women.
Concomitant medications
Bovhyaluronidase azoximer can be prescribed with other medications such as antifungal drugs, bronchial spasmolytics, antibiotics and antivirals. When administered in combination with other medicinal product (antibiotics, local anesthetics, diuretics) bovhyaluronidase azoximer increases their bioavailability and enhances their effect. In case of co-administration with high doses of salicylates, cortisone, adrenocorticotrophic hormone (ACTH), estrogens or antihistaminic drugs bovhyaluronidase azoximer enzymatic activity can decrease. It is advised that bovhyaluronidase azoximer is not administered with medicinal products containing furosemide, benzodiazepines, phenytoin.
References
Further reading
External links
Biopharmaceuticals
Copolymers | Bovhyaluronidase azoximer | [
"Chemistry",
"Biology"
] | 1,436 | [
"Pharmacology",
"Biotechnology products",
"Biopharmaceuticals"
] |
67,558,583 | https://en.wikipedia.org/wiki/Time%20in%20Albania | In Albania, the standard time is Central European Time (CET; UTC+01:00). Daylight saving time, which moves one hour ahead to Central European Summer Time, is observed from the last Sunday in March (02:00 CET) to the last Sunday in October (03:00 CEST). Albania adopted CET in 1914.
IANA time zone database
In the IANA time zone database, Albania is given the zone Europe/Tirane.
See also
Time in Europe
Time in Bosnia and Herzegovina
Time in Kosovo
References
External links
Current time in Albania at Time.is
Albania
Albania
Geography of Albania | Time in Albania | [
"Physics"
] | 126 | [
"Spacetime",
"Physical quantities",
"Time",
"Time by country"
] |
67,558,987 | https://en.wikipedia.org/wiki/Lyophyllum%20konradianum | Lyophyllum konradium is a species of mushroom-forming fungus in the family Lyophyllaceae.
Morphology
Lyophyllum konradium is distinguished from other members of Lyophyllum by the presence of well-differentiated hymenial cystidia.
Molecular phylogenetics
While the species has been treated as a member of the polyphyletic genus Lyophyllum, molecular phylogenies have placed L. konradium in a distant clade from other members of the genus. This phylogenetic isolation has led some authors to recommend the creation of a new genus, which would include L. konradium and three additional unidentified species that placed near L. konradium in the most recent phylogenetic analysis by Bellanger et al. (2015).
References
Lyophyllaceae
Fungi described in 1948
Fungus species | Lyophyllum konradianum | [
"Biology"
] | 166 | [
"Fungus stubs",
"Fungi",
"Fungus species"
] |
67,559,575 | https://en.wikipedia.org/wiki/NGC%203414 | NGC 3414 is a lenticular galaxy in the constellation Leo Minor. It was discovered by William Herschel on April 11, 1785. It is the central galaxy of a rich galaxy group. Two galaxies, NGC 3418 and UGC 5958, have similar redshifts and are within 800,000 light-years (250 kiloparsecs) of NGC 3414. It is a member of the NGC 3504 Group of galaxies, which is a member of the Leo II Groups, a series of galaxies and galaxy clusters strung out from the right edge of the Virgo Supercluster.
It has a peculiar morphology, and is listed in Halton Arp's Atlas of Peculiar Galaxies as Arp 162. The outer disc is nearly face-on, and the inner disk has a higher ellipticity and perhaps a central bar. There is a radio source that is powered by a central active galactic nucleus.
References
External links
Leo Minor
3414
Lenticular galaxies
162
032533 | NGC 3414 | [
"Astronomy"
] | 203 | [
"Leo Minor",
"Constellations"
] |
67,560,163 | https://en.wikipedia.org/wiki/Mitsuo%20Tasumi | Mitsuo Tasumi (January 23, 1937 – November 24, 2021) was a Japanese physical chemist known for his vibrational spectroscopic works on synthetic and biological macromolecules. He was Professor Emeritus of the University of Tokyo, and a former president of Saitama University, having trained
a number of physical chemists active in academia and industry. Moto-o Tasumi, a zoologist at Kyoto University, was his brother.
Career
Tasumi earned his B.Sc. (1959), M.Sc. (1961) and Ph.D. (1964) from the University of Tokyo
in the laboratories of San-Ichiro Mizushima and of
Takehiko Shimanouchi, where he reported the first phonon dispersion
of polyethylene. He spent the subsequent 33 years (1964–97) as a faculty member initially in
the Department of Biochemistry and then in the Department of Chemistry of the University of Tokyo. During this period,
he spent a year (1965–66) at University of Michigan
as a Fulbright scholar in the laboratory of Samuel Krimm and another year (1966–67)
at Polytechnic University of Milan as a postdoctoral scholar in the laboratory of Giuseppe Zerbi under Giulio Natta, a Nobel laureate.
At the University of Tokyo, Tasumi led a large group of spectroscopists, developing new
experimental and computational techniques of
infrared spectroscopy and Raman scattering spectroscopy. He is known
for establishing the theoretical basis for interpreting the spectra of synthetic
polymers (including electrical conductive polymers),
proteins, and photosynthetic systems to elucidate their relationship with the structural,
thermal, mechanical, transport, and response properties. He published several papers with Hideki Shirakawa, who was awarded a Nobel Prize jointly with Alan MacDiarmid and Alan Heeger.
He was among the earliest spectroscopists
who saw the great utility of ab initio electronic structure calculations in
understanding vibrational spectra. In particular, he established a steady-state spectroscopic method
that can determine the structures and dynamics of electronic excited states by resonance Raman excitation
profile, and applied it to polyenes including carotenoids. At the same time, he made important contributions
to the development and applications of time-resolved vibrational spectroscopies.
He is a co-author of the Protein Data Bank and the editor/author of "Introduction to Experimental Infrared Spectroscopy: Fundamentals and Practical Methods."
In 2004–08, Tasumi was the President of Saitama University after serving as Professor of Chemistry (1996-2002) of Saitama University and as Visiting Professor (2002–03) at University of California, Berkeley (stayed at the laboratory of Herbert Strauss).
In 1987–89, Tasumi was a member of the Board of Directors of the Chemical Society of Japan.
In 1994–2000, he was an Executive Committee Member of CODATA.
In 1997–99, he was the president of the Spectroscopical Society of Japan.
Honors and awards
Prize of the Society of Polymer Science, Japan (1971)
Prize of the Chemical Society of Japan (1994)
Prize of the Spectroscopical Society of Japan (1997)
The Ellis R. Lippincott Award from the Optical Society of America, Society for Applied Spectroscopy, and Coblentz Society (1999)
The Purple Ribbon Medal from the Japanese Government (1999)
The inaugural TRVS Award from the International Conference on Time-Resolved Vibrational Spectroscopy (1999)
Fellow of the Optical Society of America (2000)
Honorary Membership Award from the Society for Applied Spectroscopy (2004)
Fellow of the Society for Applied Spectroscopy (2004)
Honorary Member of the Spectroscopical Society of Japan (2007)
Honorary Member of the Japan Society for Molecular Science (2015)
Honorary Member of the Protein Science Society of Japan (2016)
Order of the Sacred Treasure from the Japanese Government (2017)
References
External links
Mitsuo Tasumi Festschrift, The Journal of Physical Chemistry A, Vol.106, Number 14 (2002).
Optical Society of America Living History: Mitsuo Tasumi
Researchmap: Mitsuo Tasumi
Chemistry Tree: Mitsuo Tasumi
1937 births
Living people
University of Tokyo alumni
Academic staff of the University of Tokyo
Physical chemists
Theoretical chemists | Mitsuo Tasumi | [
"Chemistry"
] | 884 | [
"Quantum chemistry",
"Theoretical chemistry",
"Theoretical chemists",
"Physical chemists"
] |
67,560,658 | https://en.wikipedia.org/wiki/Time%20in%20Montenegro | In Montenegro, the standard time is Central European Time (CET; UTC+01:00). Daylight saving time is observed from the last Sunday in March (02:00 CET) to the last Sunday in October (03:00 CEST). Montenegro has consistently used CET since it gained independence in 2006.
Time notation
Montenegrins use the 24-hour clock.
IANA time zone database
In the IANA time zone database, Montenegro is given the zone Europe/Podgorica.
See also
Time in Europe
Time in Albania
Time in Bosnia and Herzegovina
References
External links
Current time in Montenegro at Time.is
Geography of Montenegro | Time in Montenegro | [
"Physics"
] | 130 | [
"Spacetime",
"Physical quantities",
"Time",
"Time by country"
] |
67,561,142 | https://en.wikipedia.org/wiki/Time%20in%20Andorra | In Andorra, the standard time is Central European Time (CET; UTC+01:00). Daylight saving time is observed from the last Sunday in March (02:00 CET) to the last Sunday in October (03:00 CEST). Andorra adopted CET after WWII.
Time notation
Andorra uses the 24-hour clock.
IANA time zone database
In the IANA time zone database, Andorra is given the zone Europe/Andorra.
See also
Time in Europe
List of time zones by country
List of time zones by UTC offset
References
External links
Current time in Andorra at Time.is | Time in Andorra | [
"Physics"
] | 129 | [
"Spacetime",
"Physical quantities",
"Time",
"Time by country"
] |
67,562,153 | https://en.wikipedia.org/wiki/Catenulispora%20acidiphila | Catenulispora acidiphila is a Gram-positive bacterium from the genus of Catenulispora which has been isolated from forest soil from Gerenzano in Italy.
References
Actinomycetia
Bacteria described in 2006
Biota of Italy | Catenulispora acidiphila | [
"Biology"
] | 53 | [
"Biota by country",
"Biota of Italy"
] |
67,562,204 | https://en.wikipedia.org/wiki/Planetary%20coordinate%20system | A planetary coordinate system (also referred to as planetographic, planetodetic, or planetocentric) is a generalization of the geographic, geodetic, and the geocentric coordinate systems for planets other than Earth.
Similar coordinate systems are defined for other solid celestial bodies, such as in the selenographic coordinates for the Moon.
The coordinate systems for almost all of the solid bodies in the Solar System were established by Merton E. Davies of the Rand Corporation, including Mercury, Venus, Mars, the four Galilean moons of Jupiter, and Triton, the largest moon of Neptune.
A planetary datum is a generalization of geodetic datums for other planetary bodies, such as the Mars datum; it requires the specification of physical reference points or surfaces with fixed coordinates, such as a specific crater for the reference meridian or the best-fitting equigeopotential as zero-level surface.
Longitude
The longitude systems of most of those bodies with observable rigid surfaces have been defined by references to a surface feature such as a crater. The north pole is that pole of rotation that lies on the north side of the invariable plane of the Solar System (near the ecliptic). The location of the prime meridian as well as the position of the body's north pole on the celestial sphere may vary with time due to precession of the axis of rotation of the planet (or satellite). If the position angle of the body's prime meridian increases with time, the body has a direct (or prograde) rotation; otherwise the rotation is said to be retrograde.
In the absence of other information, the axis of rotation is assumed to be normal to the mean orbital plane; Mercury and most of the satellites are in this category. For many of the satellites, it is assumed that the rotation rate is equal to the mean orbital period. In the case of the giant planets, since their surface features are constantly changing and moving at various rates, the rotation of their magnetic fields is used as a reference instead. In the case of the Sun, even this criterion fails (because its magnetosphere is very complex and does not really rotate in a steady fashion), and an agreed-upon value for the rotation of its equator is used instead.
For planetographic longitude, west longitudes (i.e., longitudes measured positively to the west) are used when the rotation is prograde, and east longitudes (i.e., longitudes measured positively to the east) when the rotation is retrograde. In simpler terms, imagine a distant, non-orbiting observer viewing a planet as it rotates. Also suppose that this observer is within the plane of the planet's equator. A point on the Equator that passes directly in front of this observer later in time has a higher planetographic longitude than a point that did so earlier in time.
However, planetocentric longitude is always measured positively to the east, regardless of which way the planet rotates. East is defined as the counter-clockwise direction around the planet, as seen from above its north pole, and the north pole is whichever pole more closely aligns with the Earth's north pole. Longitudes traditionally have been written using "E" or "W" instead of "+" or "−" to indicate this polarity. For example, −91°, 91°W, +269° and 269°E all mean the same thing.
The modern standard for maps of Mars (since about 2002) is to use planetocentric coordinates. Guided by the works of historical astronomers, Merton E. Davies established the meridian of Mars at Airy-0 crater. For Mercury, the only other planet with a solid surface visible from Earth, a thermocentric coordinate is used: the prime meridian runs through the point on the equator where the planet is hottest (due to the planet's rotation and orbit, the Sun briefly retrogrades at noon at this point during perihelion, giving it more sunlight). By convention, this meridian is defined as exactly twenty degrees of longitude east of Hun Kal.
Tidally-locked bodies have a natural reference longitude passing through the point nearest to their parent body: 0° the center of the primary-facing hemisphere, 90° the center of the leading hemisphere, 180° the center of the anti-primary hemisphere, and 270° the center of the trailing hemisphere. However, libration due to non-circular orbits or axial tilts causes this point to move around any fixed point on the celestial body like an analemma.
Latitude
Planetographic latitude and planetocentric latitude may be similarly defined.
The zero latitude plane (Equator) can be defined as orthogonal to the mean axis of rotation (poles of astronomical bodies).
The reference surfaces for some planets (such as Earth and Mars) are ellipsoids of revolution for which the equatorial radius is larger than the polar radius, such that they are oblate spheroids.
Altitude
Vertical position can be expressed with respect to a given vertical datum, by means of physical quantities analogous to the topographical geocentric distance (compared to a constant nominal Earth radius or the varying geocentric radius of the reference ellipsoid surface) or altitude/elevation (above and below the geoid).
The areoid (the geoid of Mars) has been measured using flight paths of satellite missions such as Mariner 9 and Viking. The main departures from the ellipsoid expected of an ideal fluid are from the Tharsis volcanic plateau, a continent-size region of elevated terrain, and its antipodes.
The selenoid (the geoid of the Moon) has been measured gravimetrically by the GRAIL twin satellites.
Ellipsoid of revolution (spheroid)
Reference ellipsoids are also useful for defining geodetic coordinates and mapping other planetary bodies including planets, their satellites, asteroids and comet nuclei. Some well observed bodies such as the Moon and Mars now have quite precise reference ellipsoids.
For rigid-surface nearly-spherical bodies, which includes all the rocky planets and many moons, ellipsoids are defined in terms of the axis of rotation and the mean surface height excluding any atmosphere. Mars is actually egg shaped, where its north and south polar radii differ by approximately , however this difference is small enough that the average polar radius is used to define its ellipsoid. The Earth's Moon is effectively spherical, having almost no bulge at its equator. Where possible, a fixed observable surface feature is used when defining a reference meridian.
For gaseous planets like Jupiter, an effective surface for an ellipsoid is chosen as the equal-pressure boundary of one bar. Since they have no permanent observable features, the choices of prime meridians are made according to mathematical rules.
Flattening
For the WGS84 ellipsoid to model Earth, the defining values are
(equatorial radius): 6 378 137.0 m
(inverse flattening): 298.257 223 563
from which one derives
(polar radius): 6 356 752.3142 m,
so that the difference of the major and minor semi-axes is . This is only 0.335% of the major axis, so a representation of Earth on a computer screen would be sized as 300 pixels by 299 pixels. This is rather indistinguishable from a sphere shown as 300pix by 300pix. Thus illustrations typically greatly exaggerate the flattening to highlight the concept of any planet's oblateness.
Other values in the Solar System are for Jupiter, for Saturn, and for the Moon. The flattening of the Sun is about .
Origin of flattening
In 1687, Isaac Newton published the Principia in which he included a proof that a rotating self-gravitating fluid body in equilibrium takes the form of an oblate ellipsoid of revolution (a spheroid). The amount of flattening depends on the density and the balance of gravitational force and centrifugal force.
Equatorial bulge
Generally any celestial body that is rotating (and that is sufficiently massive to draw itself into spherical or near spherical shape) will have an equatorial bulge matching its rotation rate. With Saturn is the planet with the largest equatorial bulge in our Solar System.
Equatorial ridges
Equatorial bulges should not be confused with equatorial ridges. Equatorial ridges are a feature of at least four of Saturn's moons: the large moon Iapetus and the tiny moons Atlas, Pan, and Daphnis. These ridges closely follow the moons' equators. The ridges appear to be unique to the Saturnian system, but it is uncertain whether the occurrences are related or a coincidence. The first three were discovered by the Cassini probe in 2005; the Daphnean ridge was discovered in 2017. The ridge on Iapetus is nearly 20 km wide, 13 km high and 1300 km long. The ridge on Atlas is proportionally even more remarkable given the moon's much smaller size, giving it a disk-like shape. Images of Pan show a structure similar to that of Atlas, while the one on Daphnis is less pronounced.
Triaxial ellipsoid
Small moons, asteroids, and comet nuclei frequently have irregular shapes. For some of these, such as Jupiter's Io, a scalene (triaxial) ellipsoid is a better fit than the oblate spheroid. For highly irregular bodies, the concept of a reference ellipsoid may have no useful value, so sometimes a spherical reference is used instead and points identified by planetocentric latitude and longitude. Even that can be problematic for non-convex bodies, such as Eros, in that latitude and longitude don't always uniquely identify a single surface location.
Smaller bodies (Io, Mimas, etc.) tend to be better approximated by triaxial ellipsoids; however, triaxial ellipsoids would render many computations more complicated, especially those related to map projections. Many projections would lose their elegant and popular properties. For this reason spherical reference surfaces are frequently used in mapping programs.
See also
Apparent longitude
Areography (geography of Mars)
Astronomical coordinate systems
List of tallest mountains in the Solar System
Planetary cartography
Planetary surface
Topography of Mars
Selenography (Topography of the Moon)
References
Planetary science
Astronomical coordinate systems
Coordinate systems
Astronomy
Astrometry
Geodesy
Cartography
Navigation | Planetary coordinate system | [
"Astronomy",
"Mathematics"
] | 2,150 | [
"Applied mathematics",
"Astrometry",
"Astronomical coordinate systems",
"nan",
"Coordinate systems",
"Planetary science",
"Geodesy",
"Astronomical sub-disciplines"
] |
67,562,562 | https://en.wikipedia.org/wiki/Lydicamycin | Lydicamycin is an organic compound with the molecular formula C47H74N4O10. Lydicamycin is an antibiotic with activity against Gram-positive bacteria. The bacteria Streptomyces lydicamycinicus and Streptomyces platensis produces lydicamycin.
References
Further reading
Antibiotics
Pyrrolidines
Enols
Guanidines | Lydicamycin | [
"Chemistry",
"Biology"
] | 85 | [
"Enols",
"Biotechnology products",
"Guanidines",
"Functional groups",
"Organic compounds",
"Antibiotics",
"Biocides",
"Organic compound stubs",
"Organic chemistry stubs"
] |
67,564,037 | https://en.wikipedia.org/wiki/Clitopilus%20amygdaliformis | Clitopilus amygdaliformis is a species of fungus in the family Entolomataceae native to China, formally described in 2007.
References
Entolomataceae
Fungi of China
Fungi described in 2007
Fungus species | Clitopilus amygdaliformis | [
"Biology"
] | 48 | [
"Fungi",
"Fungus species"
] |
67,565,180 | https://en.wikipedia.org/wiki/Transition%20metal%20complexes%20of%20aldehydes%20and%20ketones | Transition metal complexes of aldehydes and ketones describes coordination complexes with aldehyde (RCHO) and ketone ligands. Because aldehydes and ketones are common, the area is of fundamental interest. Some reactions that are useful in organic chemistry involve such complexes.
Structure and bonding
In monometallic complexes, aldehydes and ketones can bind to metals in either of two modes, η1-O-bonded and η2-C,O-bonded. These bonding modes are sometimes referred to sigma- and pi-bonded. These forms may sometimes interconvert.
The sigma bonding mode is more common for higher valence, Lewis-acidic metal centers (e.g., Zn2+). The pi-bonded mode is observed for low valence, electron-rich metal centers (e.g., Fe(0) and Os(0)).
For the purpose of electron-counting, O-bonded ligands count as 2-electron "L ligands": they are Lewis bases. η2-C,O ligands are described as analogues of alkene ligands, i.e. the Dewar-Chatt-Duncanson model.
η2-C,O ketones and aldehydes can function as bridging ligands, utilizing a lone pair of electrons on oxygen. One such complex is , which features a ring.
Related ligands
Related to η1-O-bonded complexes of aldehydes and ketones are metal acetylacetonates and related species, which can be viewed as a combination of ketone and enolate ligands.
Reactions
Some η2-aldehyde complexes insert alkenes to give five-membered metallacycles.
η1-Complexes of alpha-beta unsaturated carbonyls exhibit enhanced reactivity toward dienes. This interaction is the basis of Lewis-acid catalyzed Diels-Alder reactions.
References
Organometallic chemistry
Transition metals
Coordination chemistry | Transition metal complexes of aldehydes and ketones | [
"Chemistry"
] | 416 | [
"Organometallic chemistry",
"Coordination chemistry"
] |
74,719,608 | https://en.wikipedia.org/wiki/Earliest%20eligible%20virtual%20deadline%20first%20scheduling | Earliest eligible virtual deadline first (EEVDF) is a dynamic priority proportional share scheduling algorithm for soft real-time systems.
Algorithm
EEVDF was first described in the 1995 paper "Earliest Eligible Virtual Deadline First : A Flexible and Accurate Mechanism for Proportional Share Resource Allocation" by Ion Stoica and Hussein Abdel-Wahab. It uses notions of virtual time, eligible time, virtual requests and virtual deadlines for determining scheduling priority. It has the property that when a job keeps requesting service, the amount of service obtained is always within the maximum quantum size of what it is entitled.
Linux kernel scheduler
In 2023, Peter Zijlstra proposed replacing the Completely Fair Scheduler (CFS) in the Linux kernel with an EEVDF process scheduler. The aim was to remove the need for CFS "latency nice" patches. The EEVDF scheduler replaced CFS in version 6.6 of the Linux kernel.
See also
Brain Fuck Scheduler
Earliest deadline first scheduling (EDF)
nice (Unix)
SCHED_DEADLINE
References
Processor scheduling algorithms
Real-time computing
Linux kernel process schedulers | Earliest eligible virtual deadline first scheduling | [
"Technology"
] | 228 | [
"Real-time computing"
] |
74,721,750 | https://en.wikipedia.org/wiki/Kenneth%20Ikechukwu%20Ozoemena | Kenneth Ikechukwu Ozoemena is a Nigerian physical chemist, materials scientist, and academic. He is a research professor at the University of the Witwatersrand (Wits) in Johannesburg where he Heads the South African SARChI Chair in Materials Electrochemistry and Energy Technologies (MEET), supported by the Department of Science and Innovation (DSI), National Research Foundation (NRF) and Wits.
Ozoemena group conducts interdisciplinary research across physics, chemistry, biomedical, chemical, and metallurgical engineering. He has authored numerous peer-reviewed articles, 11 book chapters, and edited books, including Nanomaterials for Fuel Cell Catalysis, and Nanomaterials in Advanced Batteries and Supercapacitors.
Ozoemena became a Fellow of the Royal Society of Chemistry (FRSC) in 2011, Fellow of the African Academy of Sciences (FAAS) in 2015, and a Member of the Academy of Science of South Africa (ASSAf) in 2016. He serves as an Associate Editor for Electrocatalysis and co-Editor-in-Chief of Electrochemistry Communications.
Earl life and education
He is an indigene of Obinikpa Umuokpara, Okohia in Umuna, Onuimo local government area of Imo State, Nigeria. Ozoemena earned his Baccalaureate degree in Industrial Chemistry from the University of Abia in 1992 and went on to receive master's degrees in Chemistry and Pharmaceutical Chemistry in 1997 and 1998, respectively, from the University of Lagos. In 2003, he completed his Ph.D. at Rhodes University in South Africa and served as a Research Fellow at the University of Pretoria.
Career
Following his Ph.D., Ozoemena began his academic career as an Andrew W. Mellon Lecturer of Chemistry at Rhodes University in 2004 and held an appointment at the University of Pretoria as a Senior Lecturer of Chemistry in 2006, and later as Extraordinary Professor of Chemistry from 2009 to 2017. He was also appointed as an Extraordinary Professor of Chemistry at the University of the Western Cape from 2011 to 2014, and an Honorary Professor of Chemistry at the University of the Witwatersrand from 2014 to 2017. Subsequently, in 2017, after about an 8-year stint at the Council for Scientific and Industrial Research (CSIR), he was appointed as professor, and later promoted to research professor at the School of Chemistry of the University of the Witwatersrand. He serves as an Honorary Visiting professor at the Wuhan University of Technology, China.
Ozoemena was elected African representative of the International Society of Electrochemistry from 2010 to 2015 and Chair of the Scientific Meeting Committee (SMC) of the International Society of Electrochemistry. He was the Chair of the Organising Committee of the 70th Annual Meeting of the International Society of Electrochemistry (ISE) Durban, the first conference of the ISE on the African continent. Subsequently, he served as the lead Guest Editor of the special issue of the conference in Electrochimica Acta.
Research
Ozoemena has focused his research in the field of materials electrochemistry, with a specific interest in advanced batteries, fuel cells, and electrochemical sensors as the primary aspects of investigation.
Lithium-ion batteries
Ozoemena has worked on improving the structural and electrochemical properties of lithium-ion batteries. One of his innovations include the use of microwave-assisted synthesis to mitigate the problems of manganese dissolution and the so-called Jahn-Teller distortion which conspire against the development and commercialization of high-energy and low-cost manganese-based cathode materials.
Aqueous mobile ion batteries & supercapacitors
Ozoemena's enquiry on the microwave-assisted synthesis and use of low cost and environmentally friendly manganese-based raw materials has led to the discovery of a new strategy of making triplite manganese fluorophosphate. In addition, Ozoemena group has demonstrated that nanostructured manganese-based complexes are promising materials for the development of high-performance supercapacitors and pseudocapacitors.
Fuel cells & electrolyzers
Ozoemena worked on the use of microwave-assisted synthesis to bring about ‘top-down’ nanosizing of palladium catalysts, introducing the term “MITNAD” which is an acronym for “microwave-induced top-down nanostructuring and decoration”. He has continued to explore the application of this technique and related techniques for the development of high-performance electrocatalysts for fuel cells and electrolyzers.
Zinc-ion and rechargeable zinc-air batteries
Ozoemena and collaborators have studied several electrode materials that can enhance the efficacy of zinc-ion and rechargeable zinc-air batteries (RZAB). The key research focus in this field has been to develop real and relevant RZAB technology for stationary and mobile applications.
Electrochemical sensors
Ozoemena has contributed in connecting biomedicine with electrochemistry, resulting in the creation of electrochemical bio- and immuno-sensors capable of detecting diseases that are mostly found in resource-limited countries, including tuberculosis in HIV-positive patients, vibrio cholera toxins in water bodies, substance abuse such as tramadol, and human papillomavirus (HPV) biomarkers for cervical cancer.
Awards and honors
2003-2013 – World's top 1% of Scientists within Chemistry, Thomson Reuters’ ISI Essential Science Indicators
2008 – Chartered Chemist (CChem), Royal Society of Chemistry
2011 – Elected Fellow, Royal Society of Chemistry
2014 – The CEO's Award, Council for Scientific & Industrial Research (CSIR)
2014 – Listed as #2 amongst the “Twenty most productive South African authors of energy papers (2000–2011)”, Academy of Science of South Africa (ASSAf).
2015 – Elected Fellow, African Academy of Sciences
2016 – Elected member, Academy of Science of South Africa (ASSAf)
2016 – Innovation Award, Council for Scientific & Industrial Research (CSIR)
2019 – World Top 2% Scientists, Stanford University, PLoS Biology
2020 – World Top 2% Scientists, PLoS Biology
2021 – SARChI Chair (Tier 1), DSI-NRF-Wits
2023 – 'A'-rated Scientist, National Research Foundation (NRF)
2023 - Vice President (Southern Africa) and member of the governing council of the African Academy of Sciences
Bibliography
Edited books
Recent Advances in Analytical Electrochemistry (2007) ISBN 978-8178952741
Nanomaterials in Advanced Batteries and Supercapacitors (2016) ISBN 978-3319260808
Nanomaterials for Fuel Cell Catalysis (2016) ISBN 978-3319262499
Selected articles
Mathebula, N.S., Pillay, J., Toschi, G., Verschoor, J.A. & Ozoemena, K.I. (2009). Recognition of anti-mycolic acid antigens on gold electrode: A potential impedimetric immunosensing platform for active tuberculosis. Chemical Communications, 3345–3347 (“HOT ARTICLE”). doi.org/10.1039/B905192A
Jafta, C.J., Mathe, M.K., Manyala, N., Roos, W.D. & Ozoemena, K.I. (2013). Microwave-Assisted Synthesis of High-Voltage Nanostructured LiMn1.5Ni0.5O4 spinel: Tuning the Mn3+ Content and Electrochemical Performance, ACS Applied Materials & Interfaces, 5, 7592–7598. doi.org/10.1021/am401894t
Fashedemi, O.O., Miller, H.A., Marchionni, A., Vizza, F. & Ozoemena, K.I. (2015). Electro-oxidation of ethylene glycol and glycerol at palladium-decorated FeCo@Fe core–shell nanocatalysts for alkaline direct alcohol fuel cells: functionalized MWCNT supports and impact on product selectivity. Journal of Materials Chemistry A, 3, 7145–7156. doi.org/10.1039/C5TA00076A
Ozoemena, K. I. (2016). Nanostructured platinum-free electrocatalysts in alkaline direct alcohol fuel cells: catalyst design, principles and applications. RSC Aadvances, 6(92), 89523-89550 doi.org/10.1039/C6RA15057H
Raju, K., Han, H., Velusamy, D.B., Jiang, Q., Yang, H., Nkosi, F.P., Palaniyandy, N., Makgopa, K., Bo, Z. & Ozoemena, K.I. (2020). Rational Design of 2D Manganese Phosphate Hydrate Nanosheets as Pseudocapacitive Electrodes. ACS Energy Letters 5, 23–30; doi.org/10.1021/acsenergylett.9b02299
Peteni, S., Ozoemena, O.C., Khawula, T., Haruna, A.B., Rawson, F.J., Shai, L.J., Ola, O. & Ozoemena, K.I. (2023). Electrochemical Immunosensor for Ultra-Low Detection of Human Papillomavirus Biomarker for Cervical Cancer. ACS Sensors, 8 (7), 2761–2770; doi.org/10.1021/acssensors.3c00677
References
Living people
South African chemical engineers
Materials scientists and engineers
Nigerian physicists
Academic staff of the University of the Witwatersrand
Cornell University faculty
Abia State University alumni
University of Lagos alumni
Rhodes University alumni
University of Pretoria alumni
Fellows of the Royal Society of Chemistry
Year of birth missing (living people)
21st-century Nigerian scientists | Kenneth Ikechukwu Ozoemena | [
"Materials_science",
"Engineering"
] | 2,121 | [
"Materials scientists and engineers",
"Materials science"
] |
74,724,476 | https://en.wikipedia.org/wiki/Vladim%C3%ADr%20Mandl | Vladimír Mandl (20 March 1899 – 8 January 1941) was a Czechoslovak lawyer and university lecturer. He published works on a variety of topics in Czech, German, French and English, focusing especially on private and transportation law issues.
Mandl authored the first stand-alone treatise on space law in 1932. For this publication – which preceded the launch of Sputnik 1 by 25 years – he is considered by some to be the "father of space law".
Life
Early life and education
Vladimír Mandl was born on 20 March 1899 in Plzeň, then part of Austria-Hungary. He was the son of , who later became the mayor of Plzeň (1917–1919), and Růžena Mandlová née Čiperová. He was one of three siblings, but his brother Matouš Mandl died shortly after birth. His uncle was the painter . Before Mandl reached his fourteenth birthday, he is said to have built his first Blériot-type monoplane and thus showed a keen interest into modern transportation from an early age.
After his high school education, Mandl entered the faculty of law of the Charles University of Prague. There he studied under , an expert on civil procedure, and graduated on 24 November 1921 with a doctorate in law.
Lawyer and author on legal topics
After his graduation, Mandl practiced law from 1921 to 1927 in the law office of in Prague and his father's law office in Plzeň. After completing his bar exam, he opened his own law office on 1 March 1927.
Following graduation, Mandl became a prolific writer on a range of legal topics, with a particular focus on private law issues and the legal aspects of technological innovations. In 1925, he authored a paper on evidence for the congress of Czechoslovak lawyers and in 1926, he penned a self-published monograph on Czechoslovakian marriage law. He then turned to transportation law and first wrote a treatise on aviation law, published by the (the West Bohemia Aeroclub) in 1928, and then in 1929, a tome on the Automobile Act of 9 August 1908 and its reform. His work on aviation law was the first work on this area of law in Czech and dealt with a variety of topics ranging from air transportation contracts to aerial warfare. It was awarded the state prize of the Czechoslovak Ministry of Justice in 1928.
In 1929, Mandl turned his legal interests into practice and obtained a private pilot licence. Mandl continued his writings on the law of aviation and published his first book in German in the same year; it dealt with the Czechoslovak law of aviation.
Probably to focus more on his scholarly interests, Mandl pursued an academic career from the late twenties onwards. To obtain a Habilitation, a necessity for a professorship, he submitted his 1928 work on aviation law as a Habilitation thesis to the Czech Technical University in Prague. His thesis was unanimously approved and his test lecture on the liability of contractors for damage was held successfully on 30 April 1930; the Czechoslovak minister of education then confirmed him as a on 30 September 1932 with a for the law of industrial enterprises.
Concurrently, Mandl successfully obtained a German doctorate in law: He received his PhD on 20 June 1931 from the University of Erlangen–Nuremberg with a dissertation on tort law titled (Civilian Construction of Tort Law).
During this time Mandl continued to publish new works: In 1932 he, for example, authored a work on the 1919 Paris Convention in Czech and in 1935, he published an article on the parachute in French.
Spaceflight and space law
Mandl had a keen interest in the possibility of spaceflight, in which he firmly believed. As an avid writer, he began to publish in this area as well: In 1932, he published a work in Czech on the problem of interstellar transport. It dealt, , with the works of Konstantin Tsiolkovski, Robert H. Goddard, Franz von Hoefft and Hermann Oberth on rocketry and contained a description of Mandl's own patent for a rocket, which was granted in Czechoslovakia in 1933. There is no evidence that the patented rocket was ever constructed.
He then turned to his pioneer work on space law: 25 years before Sputnik 1, the first artificial Earth satellite, was launched into space in October 1957, he contemplated the legal issues which would arise out of spaceflight in his 50-page book (Space Law: A Problem of Space Travel) written in German. To find a publisher for this work proved difficult: In Czechoslovakia Mandl did not find one and his German publisher only agreed to publish it at his own cost. Only twenty-five copies of the work were eventually sold, but this monograph is now remembered – and praised – as the first stand-alone volume on space law.
The work is separated into two parts: The present () and the future (). In the first part Mandl discusses how air law could be applied by analogy to space. In this part he deals with overflight rights over real property, he strongly argues for the application of strict liability, and he considers the sovereignty of states over their airspace.
In his deliberations about future developments, he foresees the legislators becoming active in this field of law and argues for licencing of space flights and the application of strict liability. Going further, Mandl discusses the future exploitation of raw materials in space and argues that the sovereignty of states over their airspace will end at the point where space begins; in space no sovereignty exists according to Mandl (). The final passage of Mandl's considerations on the future discusses the implications of regular spaceflight and the colonization of new worlds on statehood and national sovereignty. According to Mandl, many humans would opt to live on new worlds. In these newly settled worlds, no state could use methods of legal compulsion and citizens could escape legal consequences on earth by going to these celestial bodies. Mandl thinks that this will result in a new private society (), where state and citizens are equal, and no method of state sovereignty will be left to compel the individual – essentially resulting in the breakdown of modern notions of statehood and law.
Later work, university lecturing and antisemitism
After his work on space and its law, Mandl again focused on private law and adjacent fields: In 1936, he published a short work on legal theory titled (A Causal Theory of Law) in German. And in 1938, on the eve of World War II, Mandl self-published a work titled (War and Peace).
Concurrently with his publications, Mandl taught at the Czech Technical University in Prague as an associate professor. He began teaching a course on the law of industrial enterprises in the academic year 1933–1934 and kept teaching through the academic year 1938–1939. After the Nazi occupation of Czechoslovakia all Czech universities were, however, closed in November 1939 and he accordingly had to cease his academic work.
According to research by Michal Plavec of the National Technical Museum (Prague), Mandl held strong antisemitic views. He started publishing antisemitic articles after the Munich crisis in the nationalist newspaper from December 1938. For collaboration with Nazi Germany, there is, however, no evidence.
Illness and death
Mandl contracted tuberculosis and stayed in a sanatorium in Nová Ves pod Pleší (Příbram district) in 1940. He died of the disease aged 41 on 8 January 1941 and was buried in his family's tomb at the Central Cemetery in Plzeň.
Family
Mandl married Bohumila Mandlová née Charvátová (born 5 April 1907) on 2 July 1930 in Plzeň. Their son, Petr Mandl, was born on 5 November 1933; he became a renowned mathematician.
Reception of his work on space law
Contemporaneous views
Contemporaneously, Mandl's 1932 treatise on space law was received sceptically. The legal scholar – and later member of the German resistance – Rüdiger Schleicher remarked in a 1933 review of the work in the , an important German law journal, positively on the quality of the legal arguments of Mandl but was of the strong opinion that legal issues which had not yet arisen and were not likely to arise in the foreseeable future should not be discussed by legal scholars at all because lawyers should solve and discuss legal conflicts existing in reality and should not consider purely hypothetical factual circumstances.
Modern assessment
In modern times Mandl's 1932 publication has been received much more positively: , a German space law scholar, has argued that Mandl's pleading "for new rules […], for a regime of strict liability, jurisdiction in outer space, and for nationality" was "all based on the assessment of outer space being legally different from the sovereignty-based system of the airspace". Hobe thus considered Mandl's work to be "a remarkable achievement in the year 1932". and Mahulena Hofmann opined that Mandl has "entered the history of astronautics and particularly that of space law" with his work, while others go further and consider him to be the "father" or the "founding father of space law".
Published works
A bibliography of his major published works is provided by Vladimír Kopal and Mahulena Hofmann.
English translation:
References
Notes
Citations
Bibliography
Further reading
External links
1899 births
1941 deaths
Czechoslovak lawyers
Scientists from Plzeň
Space law | Vladimír Mandl | [
"Astronomy"
] | 1,901 | [
"Space law",
"Outer space"
] |
74,725,614 | https://en.wikipedia.org/wiki/Flame%20deflector | A flame deflector, flame diverter or flame trench is a structure or device designed to redirect or disperse the flame, heat, and exhaust gases produced by rocket engines or other propulsion systems. The amount of thrust generated by a rocket launch, along with the sound it produces during liftoff, can damage the launchpad and service structure, as well as the launch vehicle. The primary goal of the diverter is to prevent the flame from causing damage to equipment, infrastructure, or the surrounding environment. Flame diverters can be found at rocket launch sites and test stands where large volumes of exhaust gases are expelled during engine testing or vehicle launch.
Design and operation
The diverter typically comprises a robust, heat-resistant structure that channels the force of the exhaust gases and flames in a specific direction, typically away from the rocket or equipment. This is essential to prevent the potentially destructive effects of the high-temperature gases and to reduce the acoustic impact of the ignition.
A flame trench can also be used in combination with a diverter to form a trench-deflector system. The flames from the rocket travel through openings in the launchpad onto a flame deflector situated in the flame trench, which runs underneath the launch structure and extends well beyond the launchpad itself. To further reduce the acoustic effects a water sound suppression system may be also used.
Notable examples
Apollo program
During the Apollo program the need for a flame deflector was a determining factor in the design of the Kennedy Space Center Launch Complex 39. NASA designers chose a two-way, wedge-type metal flame deflector. It measured 13 meters in height and 15 meters in width, with a total weight of 317 tons. Since the water table was close to the surface of the ground, the designers wanted the bottom of the flame trench at ground level. The flame deflector and trench determined the height and width of the octagonal shaped launch pad.
Space Shuttle program
During the Space Shuttle program NASA modified Launch Complex 39B at Kennedy Space Center. They installed a flame trench that was 150 meters long, 18 meters wide, and 13 meters deep. It was built with concrete and refractory brick. The main flame deflector was situated inside the trench directly underneath the rocket boosters. The V-shaped steel structure was covered with a high-temperature concrete material. It separated the exhaust of the orbiter main engines and of the solid rocket boosters into two flame trenches. It was approximately 11.6 meters high, 17.5 meters wide, and 22 meters long. The Shuttle flame trench-diverter system was refurbished for the SLS program.
Baikonur Cosmodrome
The main launch pads at the Russian launch complex of Baikonur Cosmodrome use a flame pit to manage launch exhaust. The launch vehicles are transported by rail to the launch pad, where they are vertically erected over a large flame deflector pit. A similar structure was built by the European Space Agency at its Guiana Space Centre.
SpaceX Starship launch mount
During the first orbital test flight of SpaceX's Starship vehicle in April 2023, the launch mount of Starbase was substantially damaged due to the lack of a flame diverter system. The 33 Raptor rocket engines dug a crater and scattered debris and dust over a wide area. The company designed a new water deluge based flame diverter that protects the launch mount and vehicle by spraying large quantities of water from a piece of steel equipment under the rocket. In November of the same year, the new water deluge system successfully protected the launchpad during the second orbital flight test of Starship, avoiding the cloud of dust and debris that rose up during the first test.
References
Rocket launch technologies
Fire
Rocketry
Explosion protection | Flame deflector | [
"Chemistry",
"Engineering"
] | 753 | [
"Explosion protection",
"Combustion engineering",
"Rocketry",
"Combustion",
"Explosions",
"Aerospace engineering",
"Fire"
] |
74,725,659 | https://en.wikipedia.org/wiki/Las%20Vegas%20Convention%20Center%20Loop | The Las Vegas Convention Center Loop (LVCC Loop) is an underground transportation system that serves the Las Vegas Convention Center. Operating since 2021, the system uses Tesla Model 3 cars to shuttle passengers among five stations. The Boring Company began construction in November 2019, and has since continued intermittent tunnel drilling for planned stations.
History
The Boring Company won the $48.7 million contract in May 2019. and began drilling the first tunnel on November 15, 2019, digging at about per day. The first leg tunnel was completed on February 14, 2020. The second tunnel was finished that May.
The Boring Company started testing the system with volunteers in May 2021. The test demonstrated the new transport system could move up to about 4,400 passengers per hour with an end-to-end time of about two minutes. In July 2021, the peak passenger flow was recorded at 1,355 passengers per hour.
In February 2024, following investigation, the Boring Company was issued eight violations and fined $112,000 by OSHA, which the company is contesting. Subsequently, the Las Vegas Convention and Visitors Authority (LVCVA) has assumed an active safety monitoring role in the project. That April, the Boring Company was named among the "Dirty Dozen" workplace safety offenders by the National Council of Occupational Safety and Health.
System
The transportation system consists of twin tunnels in which Tesla cars are driven by employees to shuttle passengers to stops at the Las Vegas Convention Center complex and Las Vegas transportation connections. The loop cost $53 million when it opened in June 2021 and is below ground. Passengers reach the two below-ground stations with escalators and elevators. The loop is in length and covers a 25-minute walking distance. The plan is for the cars to be autonomous vehicles in the future.
Stations
LVCC Loop South Station, Las Vegas Convention Center South at the South Hall, ground-level corner of Convention Center Drive and Joe W. Brown Drive.
LVCC Loop Central Station, Las Vegas Convention Center Central, below ground at the Center Hall on Sliver Drive.
LVCC Loop Riviera Station, for departures only, Las Vegas Convention Riviera ground level at the north end of West Hall, near Elvis Presley Blvd.
Resorts World Station on Convention Center Drive, below ground at Resorts World Las Vegas a resort, mall, and casino. At the entrance to Resorts World, .
Future stops
There are additional phases planned; the completed system will consist of of tunnels and 55 stops, including stops at Harry Reid International Airport, Allegiant Stadium, the Oakland A's future Las Vegas Stadium, Brightline West Las Vegas Station, UNLV, and downtown Las Vegas. The next planned expansion was for tunnels to the Encore and Westgate resorts.
The Boring Company tunnel boring machine, Prufrock-2, was drilling toward Encore on Las Vegas Boulevard, and had tunneled to Westgate on Paradise Road in 2023. In April 2024, the Boring Company announced the Westgate station would be opening soon. Also in April 2024, it was reported that the next tunnel began construction, to connect the convention center to a station located at 3150 Paradise Road. In May 2024, a Las Vegas Loop tunnel was drilled to Virgin Hotels Las Vegas, one of four such tunnels prepared for additional future Tesla transportation system stations. In September 2024, the tunneling operation to Paradise Road was completed.
Connections
The Loop connects to the Las Vegas Monorail at the Boingo Station, LV Monorail station at the corner of Paradise Road and East Desert Inn Road at an Island above East Desert Inn Road. Buses that are near the Loop and Las Vegas Convention Center are the: RTC 108, RTC 119 and Las Vegas Deuce.
See also
Transportation in Las Vegas
NAB Show
Consumer Electronics Show
SHOT Show
International Builders' Show
World of Concrete
Conexpo-Con/Agg
Boring Test Tunnel
Tunnel construction
Notes
References
2021 establishments in Nevada
The Boring Company
Downtown Las Vegas
Public transportation in Nevada
Paradise, Nevada
Transportation in the Las Vegas Valley
Winchester, Nevada
Underground construction | Las Vegas Convention Center Loop | [
"Engineering"
] | 824 | [
"Underground construction",
"Civil engineering",
"Construction"
] |
74,725,699 | https://en.wikipedia.org/wiki/Richard%20Lawrence%20Edwards | Richard Lawrence "Larry" Edwards is an American geochemist and Distinguished McKnight University Professor and Regents Professor at the University of Minnesota. He is one of the most cited and respected geochemists in the world, and is well-known for his contributions to modernizing the uranium-thorium (Th-230) radiometric dating technique.
Edwards earned his Ph.D from the California Institute of Technology in 1988 after studying under Gerald J. Wasserburg. His thesis, entitled High Precision Thorium-230 Ages of Corals and the Timing of Sea Level Fluctuations in the Late Quaternary, discusses the usage of Th-230 dating in the examination of corals at Santo and Malekula Islands, Vanuatu.
Edwards has made notable contributions to anthropology through dating a jawbone at 100000 years old, suggesting that modern humans had inhabited the area of China where the bone was found earlier than previously thought. His collaborations with geochemist Hai Cheng have led to the largest number of environmental science papers published in Nature Index journals by a pair of geochemists.
On January 3rd, 2025, Dr. Edwards received the highly prestigious National Medal of Science.
References
Geochemists
Radiometric dating
Year of birth missing (living people)
Living people
California Institute of Technology alumni
University of Minnesota alumni
American geochemists | Richard Lawrence Edwards | [
"Chemistry"
] | 264 | [
"Geochemists",
"Radiometric dating",
"Radioactivity",
"American geochemists"
] |
74,726,643 | https://en.wikipedia.org/wiki/Candidatus%20Phytoplasma%20palmicola | Candidatus Phytoplasma palmicola is a phytoplasma first detected in Mozambique in 2007. A symptomology similar to coconut lethal yellowing disease (LYD) was found. This same disease was then found in Côte d’Ivoire. It was discovered by Harrison et al., 2014 to be due to a species nova which they named Candidatus Phytoplasma palmicola and assigned to novel Candidatus Phytoplasma subgroup .
Distribution
Geographic range includes Mozambique and Côte d’Ivoire.
Hosts
Hosts include Cocos nucifera.
References
Coconut palm diseases
Candidatus Phytoplasma | Candidatus Phytoplasma palmicola | [
"Biology"
] | 137 | [
"Bacteria stubs",
"Bacteria"
] |
74,727,689 | https://en.wikipedia.org/wiki/Energy%20management%20system%20%28building%20management%29 | An Energy Management System is, in the context of energy conservation, a computer system which is designed specifically for the automated control and monitoring of those electromechanical facilities in a building which yield significant energy consumption such as heating, ventilation and lighting installations. The scope may span from a single building to a group of buildings such as university campuses, office buildings, retail stores networks or factories. Most of these energy management systems also provide facilities for the reading of electricity, gas and water meters. The data obtained from these can then be used to perform self-diagnostic and optimization routines on a frequent basis and to produce trend analysis and annual consumption forecasts.
Energy management systems are also often commonly used by individual commercial entities to monitor, measure, and control their electrical building loads. Energy management systems can be used to centrally control devices like HVAC units and lighting systems across multiple locations, such as retail, grocery and restaurant sites. Energy management systems can also provide metering, submetering, and monitoring functions that allow facility and building managers to gather data and insight that allows them to make more informed decisions about energy activities across their sites.
Smart Energy Management System (SEMS) usually refers to energy management systems capable of dynamically adapting and efficiently managing new energy scenatrios with minimal human intervention through the use of artificial intelligence. These systems typically include self-supervised learning (SSL) machine learning models for energy consumption and generation forecasting which allows for better planning of the operation of energy infrastructure. The models also typically take into account energy price data and through the use of mathematical optimization algorithms (typically linear programming) are able to minimize the energy costs of a given system.
Smart Energy Management Systems (SEMS) are used in both residential sector, such as SoliTek NOVA and in commercial/insdustrial applications of various types. SEMS plays a key role in most smart grid concepts as it enables use cases such as virtual power plants and demand response.
As electric vehicle (EV) charging becomes more popular smaller residential devices that manage when an EV can charge based on the total load vs total capacity of an electrical service are becoming popular. The global energy management system market is projected to grow exponentially over the next 10–15 years.
The energy management of smart grids, battery storage systems, electric mobility, and renewable energy sources is an important area of application of the Internet of Things in the context of smart homes and smart buildings.
Protocols
In residential settings, the S2 Standard was developed in 2010. The S2 Standard provides a standard communication protocol, enabling communication between smart devices and an EMS. It is an open source protocol for the energy management of energy intensive devices found in the build environment, such as photovoltaic (PV) systems, electric vehicle (EV) chargers, batteries, (hybrid) heat pumps and white goods. It is built in such a way that it can work with any flexible device from any manufacturer, and that it would work for any energy management use case. The standard was ratified as a European standard by the European Electrotechnical Committee for Standardization (CENELEC) in 2018, in the form of the EN 50491–12 series.
An EMS can provide energy efficiency through process optimization by reporting on granular energy use by individual pieces of equipment. Newer, cloud-based energy management systems provide the ability to remotely control HVAC and other energy-consuming equipment; gather detailed, real-time data for each piece of equipment; and generate intelligent, specific, real-time guidance on finding and capturing the most compelling savings opportunities.
See also
Energy accounting
Energy conservation measure
Energy management
Energy management software, software to monitor and optimize energy consumption in buildings or communities
References
Energy
Energy conservation
Management systems
Building automation
Low-energy building
Management cybernetics
Sustainable building | Energy management system (building management) | [
"Physics",
"Engineering"
] | 762 | [
"Sustainable building",
"Physical quantities",
"Building engineering",
"Automation",
"Construction",
"Energy (physics)",
"Energy",
"Building automation"
] |
74,728,128 | https://en.wikipedia.org/wiki/HD%2085628 | HD 85628 (MASCARA-4) is a binary star system in the constellation of Carina. The host star, HD 85628 A, is an A-type main-sequence star, the primary star of the system, with a hot Jupiter in orbit around it. The secondary star is HD 85628 B, a K-type main-sequence star. Little is known about it.
Nomenclature
This star system was first catalogued in the Henry Draper Catalog as HD 85628, its most common name. The Henry Draper Catalogue gave stars visible to the naked eye in suitable conditions a designation, indicating that this star can be seen with the naked eye. But in 2019, the Multi-site All-Sky Camera announced the discovery of the exoplanet HD 85628 Ab/MASCARA-4b around HD 85628 A. Thus, the primary star is sometimes catalogued as MASCARA-4.
Planetary system
In 2019, a hot Jupiter exoplanet was discovered by MASCARA using the transit method around HD 85628 A.
References
Carina (constellation)
Binary stars
A-type main-sequence stars
M-type main-sequence stars
085628
Planetary systems with one confirmed planet
Planetary transit variables | HD 85628 | [
"Astronomy"
] | 250 | [
"Carina (constellation)",
"Constellations"
] |
74,730,996 | https://en.wikipedia.org/wiki/Human-guided%20migration | Human-guided migration or human-led migration is a method of restoring migratory routes of birds bred by humans for their reintroduction into the wild.
It is a technique especially used for endangered species in which the loss of individuals and territories has caused the disappearance of their migratory routes. To prevent their extinction, captive breeding has been needed, so their subsequent release into the wild requires teaching these routes to the juveniles.
Hand-reared juveniles have been imprinted on their adoptive parents, whom they follow. After a period of flight training and adaptation to the aircraft and its noise, the juveniles accompany their adoptive parents by flying to their wintering grounds.
This technique has been used in birds such as the northern bald ibis and the whooping crane, among other species.
See also
Cross-fostering
Fostering (falconry)
Hack (falconry)
Hand-rearing
Puppet-rearing
References
Bird migration
Animal breeding
Animal reintroduction
Conservation biology | Human-guided migration | [
"Biology"
] | 190 | [
"Conservation biology"
] |
74,731,384 | https://en.wikipedia.org/wiki/Fairphone%205 | Fairphone 5 is a smartphone designed and marketed by Fairphone, following its Fairphone 4. Announced on 30 August 2023, the Fairphone 5 has been shipping since 14 September 2023. As of August 2023, the company was focused on Western Europe with no planned expansions into the United States.
Specifications
Fairphone 5 is a modular smartphone, making it easily repairable and customisable by the user. It supports 5G and Wi-Fi 6E connectivity, and has a 4,200 mAh user replaceable battery. The phone is sold in configurations with 128 GB of storage and 6 GB RAM, and 256 GB of storage and 8 GB RAM. It has three 50 MP cameras with optical image stabilization, an IP55 rating, and a 90 Hz refresh rate.
The phone ships with Android 13, though users can switch to other operating systems. It is reported that it will receive five major Android updates and eight years of security patches. This is possible because the system-on-chip it uses is intended for industrial internet of things applications and will have a longer support life than a SoC intended for consumer devices.
Reception
Samuel Gibbs of The Guardian applauded the effort to create the most sustainable and longest-lasting phone while noting the tradeoffs that come with this long-lasting phone. The Verge called the phone a "lesson in delayed gratification", referring to the higher upfront cost for a longer lasting phone. Wired described it as "mediocre" but "all about the mission."
DxOMark gave the phone a score of 108 for the camera, ranking it at 103rd among all phones, and 25th among phones within the similar price range. It mentions that the Fairphone 5 is a: "Significant improvement in camera performance, both in photo and video, over its predecessor." Android Police praised the phone for finally having a "modern design" but expressed concerns about how the processor will perform after years of use.
See also
List of open-source mobile phones
Modular phone
References
Fair trade brands
Modular smartphones
Android (operating system) devices
Mobile phones introduced in 2023
Mobile phones with user-replaceable battery
Fairphone smartphones | Fairphone 5 | [
"Engineering"
] | 441 | [
"Modular design",
"Modular smartphones"
] |
74,731,872 | https://en.wikipedia.org/wiki/Bay%20of%20Biscay%20soil | Bay of Biscay is a term used in South Australia for a dark clay soil of a highly reactive nature, forming a sticky mass when wet and shrinking during long dry spells, developing deep cracks. Though found elsewhere, it is prevalent in many parts of the Adelaide plain.
It is a particular challenge to all-masonry structures, resulting in fractured foundations and vertical cracks in walls. It is not uncommon to see older buildings with walls braced with railway iron or having long steel rods at ceiling level, holding opposite walls together.
A common type of construction in such areas is brick-veneer — essentially a timber-framed building with non-structural brick outer walls — accepting cracks as a likely, but cosmetic outcome, not affecting the building's performance.
See also
Gilgai
References
Environment of South Australia
Geology of South Australia
Building defects | Bay of Biscay soil | [
"Materials_science"
] | 167 | [
"Mechanical failure",
"Building defects"
] |
74,731,954 | https://en.wikipedia.org/wiki/Julia%20Mahamid | Julia Mahamid is a cell biologist, structural biologist, and electron microscopist at the European Molecular Biology Laboratory in Heidelberg, Germany, who utilizes biomolecular condensates and advanced cellular cryo-electron tomography to enhance the comprehension of the functional organization of the cytoplasm. She leads the Mahamid Group.
Education
Mahamid completed her Biology studies at the Technion – Israel Institute of Technology, Israel between 2000 and 2003. After that, she pursued her Master's degree in Chemistry from 2003 to 2005, at the Weizmann Institute of Science, Israel, under the guidance of Lia Addadi in collaboration with Dan Caspi. Later, from 2006 to 2010, Mahamid completed her Ph.D. studies under the supervision of Lia Addadi and Steve Weiner.
Career and research
For her postgraduate work, from 2011 to 2017, Mahamid worked as a postdoctoral researcher the guidance of Wolfgang Baumeister at the Max Planck Institute of Biochemistry in Martinsried, Germany.
Since 2017, Mahamid has been a group leader at the European Molecular Biology Laboratory in Heidelberg, Germany.
Mahamid's research is based on the development of new methods for cryo-electron tomography (cryo-ET), which is a technique for high-resolution 3D imaging of cellular machinery in its natural state. Mahamid played a key role in the development of the cryo-focused ion beam (cryo-FIB) technique that facilitated the creation of "electron-transparent windows" in cells, enabling the observation of cellular structures and macromolecular complexes in their natural environment.
Mahamid is a well-known cell biologist, structural biologist, and electron microscopist. Hence, she is frequently invited to speak at seminars, workshops, and conferences in the field.
Mahamid is on the editorial board of the Journal of Structural Biology.
Awards and honours
2017 ERC Starting Grant - 3DCellPhase-
2021 Profiled in "Author File," Nature Methods
2021 Chan Zuckerberg Initiative Visual Proteomics Imaging Grant
2023 EMBO Gold Medal
References
Living people
Microscopists
European Research Council grantees
Technion – Israel Institute of Technology alumni
Weizmann Institute of Science alumni
Year of birth missing (living people) | Julia Mahamid | [
"Chemistry"
] | 469 | [
"Microscopists",
"Microscopy"
] |
74,732,341 | https://en.wikipedia.org/wiki/Arie%20Bialostocki | Arie Bialostocki is an Israeli American mathematician with expertise and contributions in discrete mathematics and finite groups.
Education and career
Arie received his BSc, MSc, and PhD (1984) degrees from Tel-Aviv University in Israel. His dissertation was done under the supervision of Marcel Herzog. After a year of postdoc at University of Calgary, Canada, he took a faculty position at the University of Idaho, became a professor in 1992, and continued to work there until he retired at the end of 2011.
At Idaho, Arie maintained correspondence and collaborations with researchers from around the world who would share similar interests in mathematics. His Erdős number is 1. He has supervised seven PhD students and numerous undergraduate students who enjoyed his colorful anecdotes and advice. He organized the Research Experience for Undergraduates (REU) program
at the University of Idaho from 1999 to 2003 attracting
many promising undergraduates who themselves have gone on to their
outstanding research careers.
Mathematics research
Arie has published more than 50 publications. Some of Bialostocki's contributions include:
Bialostocki redefined a -injector in a finite group G to be any maximal nilpotent subgroup of satisfying , where is the largest cardinality of a subgroup of which is nilpotent of class at most . Using his definition, it was proved by several authors that in many non-solvable groups the nilpotent injectors form a unique conjugacy class.
Bialostocki contributed to the generalization of the Erdős-Ginzburg-Ziv theorem (also known as the EGZ theorem). He conjectured: if is a sequence of elements of , then contains at least zero sums of length . The EGZ theorem is a special case where . The conjecture was partially confirmed by Kisin, Füredi and Kleitman, and Grynkiewicz.
Bialostocki introduced the EGZ polynomials and contributed to generalize the EGZ theorem for higher degree polynomials. The EGZ theorem is associated with the first degree elementary polynomial.
Bialostocki and Dierker introduced the relationship of EGZ theorem to Ramsey Theory on graphs.
Bialostocki, Erdős, and Lefmann introduced the relationship of EGZ theorem to Ramsey Theory on the positive integers.
In Jakobs and Jungnickel's book "Einführung in die Kombinatorik", Bialostocki and Dierker are attributed for introducing Zero-sum Ramsey theory. In Landman and Robertson's book "Ramsey Theory on the Integers", the number is defined in honor of Bialostocki's contributions to the Zero-sum Ramsey theory.
Bialostocki, Dierker, and Voxman suggested a conjecture offering a modular strengthening of the Erdős–Szekeres theorem proving that the number of points in the interior of the polygon is divisible by , provided that total number of points . Károlyi, Pach and Tóth made further progress toward the proof of the conjecture.
In Recreational Mathematics, Arie's paper on application of elementary group theory to Peg Solitaire is a suggested reading in Joseph Gallian's book on Abstract Algebra.
References
American mathematicians
Israeli mathematicians
1948 births
Living people
Tel Aviv University alumni
Group theorists
American number theorists
Combinatorialists | Arie Bialostocki | [
"Mathematics"
] | 684 | [
"Combinatorialists",
"Combinatorics"
] |
70,466,860 | https://en.wikipedia.org/wiki/K2-2016-BLG-0005Lb | K2-2016-BLG-0005Lb is the most distant exoplanet discovered by the Kepler space telescope, being twice the distance of its previous record. Its distance is estimated at from the Earth, being discovered on January 4, 2022, thanks to an effect of gravitational microlensing from a series of data recorded in 2016, then revealed on March 31, 2022.
Star
K2-2016-BLG-0005Lb orbits a dwarf star less massive than the Sun, named K2-2016-BLG-0005L. Its mass is estimated at 0.584 ± 0.03 solar masses.
Characteristics
The exoplanet is almost an exact twin of Jupiter. It is of similar mass and orbits at almost the same orbital distance. The power of the gravitational lens allowed the team to determine that the exoplanet is about 1.1 Jovian mass, and was a projected at a distance of 4.2 astronomical units from its star at the time of observation, the average orbital distance of Jupiter being 5.2 astronomical units.
See also
Exoplanet
List of exoplanets discovered in 2023
Gravitational microlensing
Kepler Space Telescope
References
External links
K2-2016-BLG-0005Lb on the Extrasolar Planets Encyclopedia.
Exoplanets discovered in 2022
Exoplanets discovered by K2
Exoplanets detected by microlensing
Sagittarius (constellation) | K2-2016-BLG-0005Lb | [
"Astronomy"
] | 302 | [
"Sagittarius (constellation)",
"Constellations"
] |
70,467,153 | https://en.wikipedia.org/wiki/Center%20for%20Countering%20Disinformation | The Center for Countering Disinformation () is a working body of the National Security and Defense Council of Ukraine established in accordance with a decision of that council dated March 11, 2021 "On the creation of the Center for Countering Disinformation", and enacted by Presidential Decree No. 106 of March 19, 2021.
The Center ensures the implementation of measures to counteract current and projected threats to Ukraine's national security and national interests in the information sphere, ensuring Ukraine's information security, identifying and counteracting disinformation, effectively countering enemy propaganda, destructive information influences and campaigns, and preventing attempts to manipulate public opinion.
History
Established on March 11, 2021, it is a body of the National Security and Defense Council of Ukraine.
On April 2, Polina Lysenko was appointed head of the center by President Volodymyr Zelenskyy's decree. She previously held the position of assistant to the first deputy director of the National Anti-Corruption Bureau of Ukraine in 2015–2019 and worked in the Ukrainian Prosecutor General's Office in 2019–2020.
The center started functioning on April 6, 2021.
On May 7, 2021, by his Decree No. 187/2021, the President approved the regulation which stipulates that the center is subordinated to the National Security and Defense Council of Ukraine, the general direction and coordination of its activity is performed by the Secretary of the National Security and Defense Council. The center employs 52 people. The regulation also defines the concept, aims, functions, and basic rights and responsibilities of the center.
On August 19, 2021, the head of the Center Polina Lysenko took maternity leave, and the duties of the head of the center were entrusted to her first deputy Andriy Shapovalov.
On April 20, 2023, the President of Ukraine Volodymyr Zelenskyy, by his decree No. 233/2023, dismissed Polina Lysenko from the post of head of the Center for Countering Disinformation, according to the submitted application.
Aim
The Center for Countering Disinformation activities encompass such areas as defense, fight against crime and corruption, foreign and domestic policy, economy, infrastructure, environment, healthcare, social sphere, and science and technology direction. But the main focus is on countering the spread of misinformation on the Internet and fakes in the media. The Center does not have punitive functions for misinformation and will not be able to apply sanctions, but may issue submissions to the National Security and Defense Councilon certain violations.
Criticism
In July 2022, the Center for Countering Disinformation published a list of persons accused of promoting messages similar to Russian propaganda. Journalist Glenn Greenwald, included in the list, called it "McCarthyite idiocy" and several other persons from the list rejected the accusation. Quincy Institute for Responsible Statecraft criticized the list as a misstep from democratic values such as freedom of speech, an apparent attempt to discredit and silence political scientist John Mearsheimer and other U.S. and Western analysts whose views differ from the Ukrainian government. The list of Russian propagandists was removed from the website of the Center for Countering Disinformation, but its copy is saved in the Internet Archive.
On October 3, 2022, an updated list appeared on the Center's website. It was available only in Ukrainian while sourcing non-Ukrainian sources, incorrectly assigned nationalities to members of the list, and has since been deleted.
Peter Goettler, writing for libertarian Cato Institute, notes that setting up government agencies, such as the Center for Countering Disinformation, to separate truth from disinformation is an unwise idea, since they may attack opinions that don't align with the government's view. Gettler disagrees with the blacklisting of his colleague Doug Bandow and emphasizes actions like "the establishment of ill-advised truth and disinformation bureaus, and the unfair smearing of eminent scholars" don't contribute to Ukraine’s reputation. He calls on Kyiv to drop the accusations and apologize.
Notes
References
Official website of The Center for Countering Disinformation
Government agencies of Ukraine
Government agencies established in 2021
2021 establishments in Ukraine
National Security and Defense Council of Ukraine
Disinformation
Information management
Propaganda in Ukraine | Center for Countering Disinformation | [
"Technology"
] | 896 | [
"Information systems",
"Information management"
] |
70,468,113 | https://en.wikipedia.org/wiki/Clementine%202 | Clementine 2 was a proposed asteroid-interception mission that was intended to fly by two near-Earth asteroids, 433 Eros and 4179 Toutatis planned by NASA.
The probe impact at Toutatis was needed to obtain the dynamic strength of surface material and data on the properties of the regolith and on stratification below the surface, and potentially allowed the measurement of thermal diffusivity between the interior and the surface. Measurements should be done by high-resolution imagery of the impact crater and its surroundings in visible, ultraviolet, and infrared wave bands from the spacecraft flying by some 30 min after the probe strike. It was proposed to equip the probe with a lightweight mass spectrometer and dust analyzer to measure the particle sizes and distribution and the composition of the eject a cloud. This mission was planned to be launched in Jul 1995, with the Eros encounter on 13 March 1996, and the Toutatis flyby on 4 October 1996, some 440 days after launch.
The mission was a successor of Clementine, and was intended to be launched by Taurus 1110 rocket, but was cancelled in 1997.
See also
Double Asteroid Redirection Test
References
Cancelled spacecraft
Missions to near-Earth asteroids
NASA programs | Clementine 2 | [
"Astronomy"
] | 253 | [
"Astronomy stubs",
"Spacecraft stubs"
] |
70,470,600 | https://en.wikipedia.org/wiki/Phosphide%20iodide | Phosphide iodides or iodide phosphides are compounds containing anions composed of iodide (I−) and phosphide (P3−). They can be considered as mixed anion compounds. They are in the category of pnictidehalides. Related compounds include the phosphide chlorides, arsenide iodides antimonide iodides and phosphide bromides.
Phosphorus can form clusters or chains in these compounds, so that some are 1-dimensional or fibrous.
Phosphide iodides are often metallic, black or dark red in colour.
List
References
Phosphides
Iodides
Mixed anion compounds | Phosphide iodide | [
"Physics",
"Chemistry"
] | 150 | [
"Ions",
"Matter",
"Mixed anion compounds"
] |
70,473,759 | https://en.wikipedia.org/wiki/Nissan%20NR%20engine | The Nissan NR is a family of prototype four-stroke 2.0-litre single-turbocharged inline-4 racing engine, developed and produced by Nissan for the Super GT series under the Nippon Race Engine framework. The engine has been produced in a number of different configurations over the years. The NR engine is fully custom-built.
Versions
All versions of the engine are identical in performance.
NR20A (2014–2019)
NR20B (2020)
NR4S21 (2021–2023)
NR4S24 (2024–present)
Applications
Nissan GT-R NISMO GT500
Nissan Fairlady Z NISMO GT500
See also
Honda HR-414E/HR-417E/HR-420E engine, similar engines also developed under the Nippon Race Engine framework
Toyota RI engine, similar engine also developed under the Nippon Race Engine framework
References
Engines by model
Gasoline engines by model
NR
Four-cylinder engines
Straight-four engines
Nissan in motorsport | Nissan NR engine | [
"Technology"
] | 196 | [
"Engines",
"Engines by model"
] |
70,474,208 | https://en.wikipedia.org/wiki/Phase%20space%20crystal | Phase space crystal is the state of a physical system that displays discrete symmetry in phase space instead of real space. For a single-particle system, the phase space crystal state refers to the eigenstate of the Hamiltonian for a closed quantum system or the eigenoperator of the Liouvillian for an open quantum system. For a many-body system, phase space crystal is the solid-like crystalline state in phase space. The general framework of phase space crystals is to extend the study of solid state physics and condensed matter physics into phase space of dynamical systems. While real space has Euclidean geometry, phase space is embedded with classical symplectic geometry or quantum noncommutative geometry.
Phase space lattices
In his celebrated book Mathematical Foundations of Quantum Mechanics, John von Neumann constructed a phase space lattice by two commutative elementary displacement operators along position and momentum directions respectively, which is also called the von Neumann lattice nowadays. If the phase space is replaced a frequency-time plane, the von Neumann lattice is called Gabor lattice and widely used for signal processing.
The phase space lattice differs fundamentally from the real space lattice because the two coordinates of phase space are noncommutative in quantum mechanics. As a result, a coherent state moving along a closed path in phase space acquires an additional phase factor, which is similar to the Aharonov–Bohm effect of a charged particle moving in a magnetic field. There is a deep connection between phase space and magnetic field. In fact, the canonical equation of motion can also be rewritten in the Lorenz-force form reflecting the symplectic geometry of classical phase space.
In the phase space of dynamical systems, the stable points together with their neighbouring regions form the so-called Poincaré-Birkhoff islands in the chaotic sea that may form a chain or some regular two dimensional lattice structures in phase space. For example, the effective Hamiltonian of kicked harmonic oscillator (KHO). can possess square lattice, triangle lattice and even quasi-crystal structures in phase space depending on the ratio of kicking number. In fact, any arbitrary phase space lattice can be engineered by selecting an appropriate kicking sequence for the KHO.
Phase space crystals (PSC)
The concept of phase space crystal was proposed by Guo et al. and originally refers to the eigenstate of effective Hamiltonian of periodically driven (Floquet) dynamical system. Depending on whether interaction effect is included, phase space crystals can be classified into single-particle PSC and many-body PSC.
Single-particle phase space crystals
Depending on the symmetry in phase space, phase space crystal can be a one-dimensional (1D) state with -fold rotational symmetry in phase space or two-dimensional (2D) lattice state extended into the whole phase space. The concept of phase space crystal for a closed system has been extended into open quantum systems and is named as dissipative phase space crystals.
Zn PSC
Phase space is fundamentally different from real space as the two coordinates of phase space do not commute, i.e., where is the dimensionless Planck constant. The ladder operator is defined as such that . The Hamiltonian of a physical system can also be written in a function of ladder operators . By defining the rotational operator in phase space by where with a positive integer, the system has -fold rotational symmetry or symmetry if the Hamiltonian commutates with rotational operator , i.e.,
In this case, one can apply Bloch theorem to the -fold symmetric Hamiltonian and calculate the band structure. The discrete rotational symmetric structure of Hamiltonian is called phase space lattice and the corresponding eigenstates are called phase space crystals.
Lattice PSC
The discrete rotational symmetry can be extended to the discrete translational symmetry in the whole phase space. For such purpose, the displacement operator in phase space is defined by which has the property , where is a complex number corresponding to the displacement vector in phase space. The system has discrete translational symmetry if the Hamiltonian commutates with translational operator , i.e.,
If there exist two elementary displacements and that satisfy the above condition simultaneously, the phase space Hamiltonian possesses 2D lattice symmetry in phase space. However, the two displacement operators are not commutative in general . In the non-commutative phase space, the concept of a "point" is meaningless. Instead, a coherent state is defined as the eigenstate of the lowering operator via . The displacement operator displaces the coherent state with an additional phase, i.e., . A coherent state that is moved along a closed path, e.g., a triangle with three edges given by in phase space, acquires a geometric phase factor
where is the enclosed area. This geometric phase is analogous to the Aharonov–Bohm phase of charged particle in a magnetic field. If the magnetic unit cell and the lattice unit cell are commensurable, namely, there exist two integers and such that , one can calculate the band structure defined in a 2D Brillouin. For example, the spectrum of a square phase space lattice Hamiltonian displays Hofstadter's butterfly band structure that describes the hopping of charged particles between tight-binding lattice sites in a magnetic field. In this case, the eigenstates are called 2D lattice phase space crystals.
Dissipative PSC
The concept of phase space crystals for closed quantum system has been extended to open quantum system. In circuit QED systems, a microwave resonator combined with Josephson junctions and voltage bias under -photon resonance can be described by a rotating wave approximation (RWA) Hamiltonian with phase space symmetry described above. When single-photon loss is dominant, the dissipative dynamics of resonator is described by the following master equation (Lindblad equation)
where is the loss rate and superoperator is called the Liouvillian. One can calculate the eigenspectrum and corresponding eigenoperators of the Liouvillian of the system .
Notice that not only the Hamiltonian but also the Liouvillian both are invariant under the -fold rotational operation, i.e., with and . This symmetry plays a crucial role in extending the concept of phase space crystals to an open quantum system. As a result, the Liouvillian eigenoperators have a Bloch mode structure in phase space, which is called a dissipative phase space crystal.
Many-body phase space crystals
The concept of phase space crystal can be extended to systems of interacting particles where it refers to the many-body state having a solid-like crystalline structure in phase space. In this case, the interaction of particles plays an important role. In real space, the many-body Hamiltonian subjected to a perturbative periodic drive (with period ) is given by
Usually, the interaction potential is a function of two particles' distance in real space. By transforming to the rotating frame with the driving frequency and adapting rotating wave approximation (RWA), one can get the effective Hamiltonian.
Here, are the stroboscopic position and momentum of -th particle, namely, they take the values of at the integer multiple of driving period . To have the crystal structure in phase space, the effective interaction in phase space needs to be invariant under the discrete rotational or translational operations in phase space.
Phase space interactions
In classical dynamics, to the leading order, the effective interaction potential in phase space is the time-averaged real space interaction in one driving period
Here, represents the trajectory of -th particle in the absence of driving field. For the model power-law interaction potential with integers and half-integers , the direct integral given by the above time-average formula is divergent, i.e., A renormalisation procedure was introduced to remove the divergence and the correct phase space interaction is a function of phase space distance in the plane. For the Coulomb potential , the result still keeps the form of Coulomb's law up to a logarithmic renormalised "charge" , where is the Euler's number. For , the renormalised phase space interaction potential is
where is the collision factor. For the special case of , there is no effective interaction in phase space since is a constant with respect to phase space distance. In general for the case of , phase space interaction grows with the phase space distance . For the hard-sphere interaction (), phase space interaction behaves like the confinement interaction between quarks in Quantum chromodynamics (QCD). The above phase space interaction is indeed invariant under the discrete rotational or translational operations in phase space. Combined with the phase space lattice potential from driving, there exist a stable regime where the particles arrange themselves periodically in phase space giving rise to many-body phase space crystals.
In quantum mechanics, the point particle is replaced by a quantum wave packet and the divergence problem is naturally avoided. To the lowest-order Magnus expansion for Floquet system, the quantum phase space interaction of two particles is the time-averaged real space interaction over the periodic two-body quantum state as follows.
In the coherent state representation, the quantum phase space interaction approaches the classical phase space interaction in the long-distance limit. For bosonic ultracold atoms with repulsive contact interaction bouncing on an oscillating mirror, it is possible to form Mott insulator-like state in the phase space lattice. In this case, there is a well defined number of particles in each potential site which can be viewed as an example of 1D many-body phase space crystal.
If the two indistinguishable particles have spins, the total phase space interaction can be written in a sum of direct interaction and exchange interaction. This means that the exchange effect during the collision of two particles can induce an effective spin-spin interaction.
Phase space crystal vibrations
Solid crystals are defined by a periodic arrangement of atoms in real space, atoms subject to a time-periodic drive can also form crystals in phase space. The interactions between these atoms give rise to collective vibrational modes similar to phonons in solid crystals. The honeycomb phase space crystal is particularly interesting because the vibrational band structure has two sub-lattice bands that can have nontrivial topological physics. The vibrations of any two atoms are coupled via a pairing interaction with intrinsically complex couplings. Their complex phases have a simple geometrical interpretation and can not be eliminated by a gauge transformation, leading to a vibrational band structure with non-trivial Chern numbers and chiral edge states in phase space. In contrast to all topological transport scenarios in real space, the chiral transport for phase space phonons can arise without breaking physical time-reversal symmetry.
Relation to time crystals
Time crystals and phase space crystals are closely related but different concepts. They both study subharmonic modes that emerge in periodically driven systems. Time crystals focus on the spontaneous symmetry breaking process of discrete time translational symmetry (DTTS) and the protection mechanism of subharmonic modes in quantum many-body systems. In contrast, the study of phase space crystal focuses on the discrete symmetries in phase space. The basic modes constructing a phase space crystal are not necessarily a many-body state, and need not break DTTS as for the single-particle phase space crystals. For many-body systems, phase space crystals study the interplay of the potential subharmonic modes that are arranged periodically in phase space. There is a trend to study the interplay of multiple time crystals which is coined as condensed matter physics in time crystals.
References
Concepts in physics
Hamiltonian mechanics
Dimensional analysis
Dynamical systems
Quantum mechanics | Phase space crystal | [
"Physics",
"Mathematics",
"Engineering"
] | 2,387 | [
"Dimensional analysis",
"Theoretical physics",
"Quantum mechanics",
"Classical mechanics",
"Hamiltonian mechanics",
"Mechanics",
"nan",
"Mechanical engineering",
"Dynamical systems"
] |
70,476,011 | https://en.wikipedia.org/wiki/Pyrios | Pyrios is an advanced Liquid rocket booster concept proposed in 2012 by Dynetics for use on NASA's Space Launch System heavy-lift launch vehicle. Pyrios was intended to use the RP-1/LOX F-1B, a modernized version of the F-1A engine built by Aerojet Rocketdyne. Developed during the later stages of the Apollo program, the F-1A was test-fired but never flew. Several were created and stored by Rocketdyne. The company has also maintained an F-1/F-1A knowledge retention program for its engineers for the entire period the engine has been mothballed. Dynetics is now performing tests on engine components pulled from storage. Pyrios was intended to use the same attachment points as the five-segment SRBs
The name is derived from Greek mythology. Pyrois was a horse that pulled sun god Helios’ chariot.
References
Rocket stages | Pyrios | [
"Astronomy"
] | 192 | [
"Rocketry stubs",
"Astronomy stubs"
] |
70,476,313 | https://en.wikipedia.org/wiki/Monochrome-astrophotography-techniques | Monochrome photography is one of the earliest styles of photography and dates back to the 1800s. Monochrome photography is also a popular technique among astrophotographers. This is due to the omission of the Bayer filter, a colour filter array that sits in front of the CMOS or CCD sensor, allowing for a single sensor to produce a colour image.
Sensor design
Colour cameras produce colour images using a Bayer matrix, a colour filter array that sits in front of the sensor. The matrix allows light of primary colours, red, green and blue, to enter the sensor. A typical matrix arrangement consists of a 25% red pass through area, 25% blue, and 50% green. The Bayer matrix allows a single chip sensor to produce a colour image.
Many objects in deep space are made up of hydrogen, oxygen and sulphur. These elements emit light in the red, blue and red/orange spectrum respectively.
When imaging an object rich in hydrogen, the object will primarily emit light in the hydrogen-alpha/red wavelengths. In this scenario, the Bayer matrix will only allow 25% off the incoming light from the nebula to reach the sensor, as only 25% of the matrix area will allow red light to pass through.
A monochromatic sensor does not have a Bayer matrix. This means the entire sensor can be utilised to capture specific wavelengths using specialised colour filters known as narrowband filters. Many nebulae are made up of hydrogen, oxygen and sulphur. These nebulae emit light in red, blue and orange wavelengths respectively. A narrowband filter can be used for each colour to produce three discrete monochrome images. These images can then be combined to produce a colour image.
Advantages
Monochrome astrophotography has gained its popularity as a method of combating the effects of modern light-pollution. The Bayer matrix in a traditional sensor will limit the available sensor area capable of collecting light from deep space objects to approximately 25%. The remaining 75% however is still capable of collecting light, often in the form of surrounding light pollution. This can adversely affect the signal-to-noise ratio.
Removing the Bayer matrix means a narrowband filter can be used to only allow specific wavelengths of light to reach the sensor. This has the benefit of utilising the entire sensor area to maximise the amount of light collected, whilst also rejecting sources of external light pollution, vastly improving the signal-to-noise ratio.
Monochrome image processing
Colour images in typical cameras are made by combining data from red, green and blue pixels. In order to produce a colour image using a monochrome sensor, three monochrome images must be produced and combined to produce a colour image. The three monochrome images are mapped to the respective red, green and blue channels. In the case of astrophotography, this can vary to some degree, although a common colour palette is the Hubble palette, often known as "SHO". In the Hubble pallet, Sulphur is mapped to the red channel, hydrogen-alpha signals are mapped to green, and oxygen is mapped to blue
Monochrome astrophotography also requires a greater number of calibration frames. Calibration frames are used capture artefacts and dust on the image sensor and filter, and light gradients due to internal reflections in the optical train. These can then be removed from the final image. Monochrome imaging requires the use of three individual filters to produce a colour image. This means three sets of calibration frames must be generated and applied during the image processing stage. This therefore increases the amount of images that need to be stored, requiring greater amounts of storage space.
Monochrome photography also requires additional equipment. Due to the requirement of multiple filters, amateur astrophotographers often use an electronic filter wheel. This allows multiple filters to be installed, and a computer can be used to control the wheel and change filters throughout the night
References
Photography
Astronomy
Space | Monochrome-astrophotography-techniques | [
"Physics",
"Astronomy",
"Mathematics"
] | 801 | [
"Spacetime",
"Space",
"Geometry",
"nan"
] |
70,476,830 | https://en.wikipedia.org/wiki/Sarah%20Burch | Sarah Burch is a Canadian environmental scientist who is Canada Research Chair at the University of Waterloo. Her research considers strategies to respond to climate change at the community scale. She is a lead author for the IPCC Sixth Assessment Report.
Early life and education
Burch studied international relationships and environmental sciences at the University of Calgary. She was a doctoral researcher at the University of British Columbia, before moving to the United Kingdom as a postdoctoral researcher, where she worked at the University of Oxford.
Research and career
In 2013, Burch returned to Canada, where she joined the faculty at the University of Waterloo. She worked as an Assistant Professor and coordinated research fellows for the Earth System Governance Project. In 2015, Burch was appointed a Canada Research Chair in Sustainability Governance. Her research considers strategies to mitigate the impact of climate change in communities. In particular, she has studied how small businesses can contribute to global efforts for sustainability. By investigating inertia built into urban planning and governance, Burch hopes to understand the origins of carbon-intensive developments. Burch works as the Director of the Sustainability Policy Research on Urban Transformations (SPROUT) Lab. She was involved with delivering the world's first massive open online course on climate change.
After contributing to the IPCC Fourth Assessment Report, Burch was made a lead author on the IPCC Sixth Assessment Report. When the IPCC Sixth Assessment Report reported its findings in 2022, Burch explained that to avoid a climate catastrophe, the world had three years to reduce emissions.
Awards and honours
2017 Royal Society of Canada College of New Scholars
2018 Canada's Top 40 Under 40
Selected publications
References
Living people
Year of birth missing (living people)
Place of birth missing (living people)
Environmental scientists
21st-century Canadian scientists
21st-century Canadian women scientists
Canada Research Chairs
Academic staff of the University of Waterloo
University of Calgary alumni
University of British Columbia alumni | Sarah Burch | [
"Environmental_science"
] | 380 | [
"Canadian environmental scientists",
"Environmental scientists"
] |
70,477,161 | https://en.wikipedia.org/wiki/Toyota%20RI%20engine | The Toyota RI is a family of prototype four-stroke 2.0-litre single-turbocharged inline-4 racing engines, developed and produced by Toyota, for the Super GT series and Super Formula under the Nippon Race Engine framework. The RI engine is fully custom-built.
Versions
The RI engine comes in two different versions for different applications; the RI4A for use in Super Formula and the RI4AG for use in Super GT.
RI4A (2014–present, also known as TRD-01F)
RI4AG (2014–2023)
RI4BG (2024-present)
Applications
Dallara SF14
Dallara SF19
Dallara SF23
Lexus RC F GT500
Lexus LC 500 GT500
Toyota GR Supra GT500
See also
Honda HR-414E/HR-417E/HR-420E engine, similar engines also developed under the Nippon Race Engine framework
Nissan NR engine, similar engine also developed under the Nippon Race Engine framework
References
Engines by model
Gasoline engines by model
Toyota engines
Four-cylinder engines
Straight-four engines
Toyota in motorsport | Toyota RI engine | [
"Technology"
] | 227 | [
"Engines",
"Engines by model"
] |
70,477,295 | https://en.wikipedia.org/wiki/Capacity%20credit | Capacity credit (CC, also capacity value or de-rating factor) is the fraction of the installed capacity of a power plant which can be relied upon at a given time (typically during system stress), frequently expressed as a percentage of the nameplate capacity. A conventional (dispatchable) power plant can typically provide the electricity at full power as long as it has a sufficient amount of fuel and is operational, therefore the capacity credit of such a plant is close to 100%; it is exactly 100% for some definitions of the capacity credit (see below). The output of a variable renewable energy (VRE) plant depends on the state of an uncontrolled natural resource (usually the sun or wind), therefore a mechanically and electrically sound VRE plant might not be able to generate at the rated capacity (neither at the nameplate, nor at the capacity factor level) when needed, so its CC is much lower than 100%. The capacity credit is useful for a rough estimate of the firm power a system with weather-dependent generation can reliably provide. For example, with a low, but realistic (cf. Ensslin et al.) wind power capacity credit of 5%, 20 gigawatts (GW) worth of wind power needs to be added to the system in order to permanently retire a 1 GW fossil fuel plant while keeping the electrical grid reliability at the same level.
Definitions
There are a few similar definitions of the capacity credit:
effective load carrying capability (ELCC) defines the capacity value as the extra load that can be added to the system once the plant is added without degrading a chosen reliability index (usually the loss of load probability). Unlike the dimensionless CC, ELCC is expressed in power units (megawatts). California regulators, in their resource adequacy calculations, use different term, qualifying capacity (QC). For a dispatchable plant, QC is self-assessed and might go as high as the maximum power of the unit. For wind and solar, QC is based on an ELCC modeling; for cogeneration, biomass power, hydropower, and geothermal power, the history of production is used. Net qualifying capacity (NQC) is similar to QC, except it takes into account the connection of the generator to the grid, for large generating plants, ; ELCC metrics was introduced by Garver in 1966.
equivalent conventional capacity (ECC) compares the additional power of a new plant to that of a conventional power plant and directly represents the amount of the conventional generating capacity which can be replaced by a VRE plant while keeping the value of the risk index. A similar metrics, comparing the plant contribution to that of a perfect always-available-at-full-capacity plant is called an equivalent firm capacity or EFC;
percentile of peak-period availability defines the capacity value by calculating the capacity at chosen worst-case percentile (say, 5th lowest) of the power distribution during the times of the peak demand.
Values
The capacity credit can be much lower than the capacity factor (CF): in a not very probable scenario, if the riskiest time for the power system is after sunset, the capacity credit for solar power without coupled energy storage is zero regardless of its CF (under this scenario all existing conventional power plants would have to be retained after the solar installation is added). More generally, the CC is low when the times of the day (or seasons) for the peak load do not correlate well with times of high energy production. Ensslin et al. report wind CC values ranging from 40% down to 5%, with values dropping off with increased wind power penetration.
For very low penetrations (few percent), when the chance of the system actually being forced to rely on the VRE at peak times is negligible, the CC of a VRE plant is close to its capacity factor. For high penetrations, due to the fact that the weather tends to affect all plants of similar type at the same time and in the same way - and the chance of a system stress during low wind condition increases, the capacity credit of a VRE plant decreases. Greater geographical diversity of the VRE installations improves the capacity credit value, assuming a grid that can carry all necessary load. Increasing the penetration of one VRE resource also can result in increasing the CC for another one, e.g., in California, increase in solar capacity, with a low incremental CC, expected to be 8% in 2023 and dropping to 6% by 2026, helps shifting the peak demand from other sources later into the evening, when the wind is stronger, therefore the CC of the wind power is expected to increase from 14% to 22% within the same period. A 2020 study of ELCC by California utilities recommends even more pessimistic values for photovoltaics: by 2030 the ELCC of solar will become "nearly zero". The California Public Utilities Commission orders of 2021 and 2023 intend to add by 2035 additional renewable generation capacity with NQC of 15.5 GW and nameplate capacity of 85 GW, implying planned NQC for renewables (a combination of solar and wind), combined with geothermal, batteries, long-term storage, and demand response to be 15.5/85 = 18%.
In some areas peak demand is driven by air conditioning and occurs on summer afternoons and evenings, while the wind is strongest at night, with offshore wind strongest in the winter. This results in a relatively low CC for such potential wind power locations: for example in Texas a predicted average for onshore wind is 13% and for offshore wind is 7%.
In Great Britain, the solar contribution to the system adequacy is small and is primarily due to scenarios when the use of solar allows to keep the battery storage fully charged until later in the evening. The National Grid ESO in 2019 suggested planning for the following EFC-based de-rating:
References
Sources
Power engineering | Capacity credit | [
"Engineering"
] | 1,233 | [
"Power engineering",
"Electrical engineering",
"Energy engineering"
] |
70,478,462 | https://en.wikipedia.org/wiki/Hybrid%20rocket%20fuel%20regression | Hybrid rocket fuel regression refers to the process by which the fuel grain of a hybrid-propellant rocket is converted from a solid to a gas that is combusted. It encompasses the regression rate, the distance that the fuel surface recedes over a given time, as well as the burn area, the surface area that is being eroded at a given moment.
Because the quantity of fuel being burned is important for the effectiveness of combustion in the engine, the regression rate plays a fundamental role in the design and firing of a hybrid engine. Unfortunately, hybrid fuel grains tend to have extremely slow regression, requiring very long combustion chambers or complex port designs that result in excess mass. Regression rate has also proven quite difficult to predict, with advanced models still providing significant error when applied at various scales and with differing fuels. Recent research has centered around the development of more accurate models coupled with research into techniques for increasing regression rate.
Regression rate
In contrast to solid rocket motors, hybrids exhibit significant dependence on the size of the port and low dependence on chamber pressure under normal conditions. Because they are dominated by thermodynamic forces, models typically emerge via a heat transfer calculation. Marxman provided the first attempt at an a priori model of hybrid regression, basing the rate on a heat transfer equilibrium calculation and assuming unity for the Prandtl and Lewis numbers. He eventually developed the below equation, using for instantaneous local mass flux, as distance along the port, rho for density of the fuel, for viscosity of the main-stream gas flow, for the velocity ratio between gas in the main stream and gas at the flame, and for the ratio considering the enthalpy difference from flame to fuel surface () in comparison to the effective heat of vaporization () for the fuel.Though the model showed large errors when used to predict regression rate for an annular port, the strong dependence on flux was a key finding. Unfortunately, many components of the equation are extremely difficult to determine, so most engineers focused on developing models based on testing, fitting the regression rate to a power function by effectively combining most of the terms into one coefficient that is assumed constant throughout the burn. It was typically simplified into a basic equation by considering the average regression over time for a test, fitting coefficients , and based on regression testing.Where G is the mass flux of propellant and x is the distance along the fuel grain. Though Marxman's initial math indicates that and , data typically ranges from 0.5 to 0.8 for and usually shows less dependence than predicted on . By averaging the regression out over the length of the fuel grain, the commonly used space-time average regression equation is created (also typically using , the flux of oxidizer, for the flux term instead of for flux of oxidizer and fuel).Many alternative equations for regression rate have been derived, usually constructed by reconsidering the assumptions made by Marxman but using the same diffusion-limited calculation approach. A model published by Karabeyoglu, for example, provides a more accurate approach by considering variation in the Prandtl number, accounting for entrance effects in the Reynolds number, and moving the flame sheet location to the stoichiometric location.
Similar concepts can be seen in an extension by Whitmore, where the Prandtl number is approximated as 0.8 and the skin friction coefficient is recalculated to consider blowing and the flow development along the grain length.
Both improved formulas appear to show a better relationship with tested data.
Regression enhancements
Liquifying fuels
The simplest technique for increasing the regression rate is to use a different fuel. Solids with lower molecular masses tend to have lower viscosities, a quality which generally correlates with a decrease in the required energy for gasification. Taken to the extreme, a new phenomenon actually emerges, where a melt layer at the surface of the fuel allows droplets to be entrained as oxidizer flows past. At the flux levels commonly seen in hybrid rocketry, this entrainment actually accounts for the largest portion of regression (dominating vaporization).
The concept was originally discovered during a brief research period in which AFRL and Orbital Technologies Corporation (ORBITEC) tested several cryogenic fuels in an effort to increase specific impulse. Using solidified pentane, they found regression rates vastly increased over traditional hybrid fuels. Several tests with paraffin also foreshadowed modern liquifying rocket technology, with the Peregrine rocket among others leading the way for further development.
The alternative regression method does supply some other issues, mainly a reduction in combustion efficiency. Because of the large particle size, the entrained droplets may not be fully consumed before flowing out of the nozzle and leaving the engine. Indeed, paraffin has a tendency to even slough off large fragments, greatly reduces combustion efficiency and potentially contributing to combustion instability.
Complex geometry
Although it is much harder to predict, complex grain geometries offer another technique for increasing regression rate and burn area in order to greatly increase fuel flow.
Using non-circular port cross sections increases the area exposed to the oxidizer to be gasified, especially at the start of the burn. However, as the fuel continues to regress it will begin to round out the shape because regression generally occurs normal to the fuel’s surface, and corners tend to regress faster. Generally, this will cause the O/F ratio to shift away from stoichiometric.
Some of the first attempts at complex geometries were wagon wheel designs developed by the United Technology Center. Though they massively increase fuel flow, wagon wheels require that a significant portion of fuel is left behind, or the structure could break apart.
More recently, helical designs have been used to create a centripetal component of flow, reducing blowing and providing greater friction between the oxidizer and fuel in order to increase convection. Analysis at the University of Utah concluded that regression rates generally increased by at least a factor of two, up to even a factor of four. In general, helical regression rate is modeled by several multiplicative adjustments to the skin friction coefficient and to the blowing coefficient.
Burn area
The burn area refers to the surface exposed to the heat of the combustion chamber, and it is just as pivotal to the regression of the rocket as the regression rate itself, since the volume flow rate of fuel is usually given by the regression rate multiplied by the burn area. Depending on the complexity of the grain geometry, it can also be quite difficult to calculate. At its simplest form, a tube-shaped fuel grain has a burn area of added to the area on both ends. However, a star-shaped fuel grain could require the use of CAD or other geometric software to determine the surface area, particularly as the surface area regresses along the normals, often creating highly irregular geometry.
In fact, the process is even slightly more complicated because corners protruding into the combustion chamber will regress more quickly than their circular counterparts, since they are exposed to heat on both sides. To model the problem, Bath developed a technique of iteratively blurring pixels and removing those that fall below a certain threshold of brightness. Using the image processing to generate a table of surface area outputs for a given volume, it can easily be implemented into a model for regression of the fuel grain over time.
Unfortunately, most models still require an empirical factor that depends on variations in fuel and oxidizer flow paths for different port geometries. In the case of the image blurring model, predictions of regression are also dependent on the settings used in the image processing program.
Models of burn area based on 2D cross sections lose another component of accuracy because they assume regression in the radial direction. For a helical grain, for example, the burn area predicted by Bath's model would be incorrect.
Regression testing
Because of the lack of accurate prediction methods, each system should generally be tested in full configuration to accurately determine the regression rate before flight. Typically, data points for several identical grains tested under different flux conditions are fitted to the space-time averaged power function. Initially, methods for fitting the power function were often left ambiguous in publications due to variation in the possible calculations for average mass flux, making it difficult to compare findings. A now commonly-referenced study by Karabeyoglu indicates that the easiest measurement, the port diameter average, also provides the most accurate results.
References
Hybrid-propellant rockets
Rocket engines | Hybrid rocket fuel regression | [
"Technology"
] | 1,712 | [
"Rocket engines",
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70,478,503 | https://en.wikipedia.org/wiki/2%2C4%2C6-Trichlorobenzoyl%20chloride | 2,4,6-Trichlorobenzoyl chloride or Yamaguchi's reagent is an chlorinated aromatic compound that is commonly used in a variety of organic syntheses.
Yamaguchi esterification
It is the primary reactant in Yamaguchi esterification. 2,4,6-Trichlorobenzoyl chloride readily reacts with alcohols. This newly formed reagent, when mixed with a stoichiometric amount of 4-dimethylaminopyridine, cyclizes and forms esters. This reaction creates 2,4,6-trichlorobenzoic acid as a byproduct.
Preparation
2,4,6-Trichlorobenzoyl chloride is prepared by reacting 2,4,6-trichloroaniline with n-butyllithium in a carbon dioxide atmosphere. This produces 2,4,6-trichlorobenzoic acid, which can then be refluxed in thionyl chloride to form 2,4,6-trichlorobenzoyl chloride.
Since 2,4,6-trichlorobenzoic acid is produced as a by product of the Yamaguchi esterification process, it can be refluxed again to recreate 2,4,6-trichlorobenzoyl chloride.
References
Chlorobenzene derivatives
Acyl chlorides
Reagents for organic chemistry | 2,4,6-Trichlorobenzoyl chloride | [
"Chemistry"
] | 299 | [
"Reagents for organic chemistry"
] |
70,479,873 | https://en.wikipedia.org/wiki/HWA%20AFR%20Turbo%20engine | The HWA AFR Turbo is a prototype four-stroke 2.0-litre single-turbocharged inline-4 gasoline racing engine, developed and produced jointly by HWA, in partnership and collaboration with Aston Martin, for Deutsche Tourenwagen Masters. The HWA inline-4 is engine rated at , with extra available on push-to-pass, and drives the rear wheels of the Vantage through a 6-speed semi-automatic transmission.
Applications
Aston Martin Vantage DTM
References
Aston Martin
Gasoline engines by model
Engines by model
Deutsche Tourenwagen Masters
Straight-four engines | HWA AFR Turbo engine | [
"Technology"
] | 119 | [
"Engines",
"Engines by model"
] |
70,480,380 | https://en.wikipedia.org/wiki/Science%20and%20technology%20in%20Spain | Science and technology in Spain relates to the set of policies, plans and programs carried out by the Spanish Ministry of Science and Innovation and other organizations aimed at research, development and innovation (R&D&I), as well as the reinforcement Spanish scientific and technological infrastructures and facilities such as universities and commercial laboratories.
Spain has become the ninth scientific power in the world with 2.5% of the total number of scientific publications, thus surpassing Russia in the world ranking of scientific production and surpassing Switzerland and Australia in scientific quality.
Regulations
Science Law of 1986
Law 13/1986 on the "Promotion and General Coordination of Scientific and Technical Research" placed science for the first time on the Spanish political agenda, laying the foundations for research, as well as its financing, organization and coordination between the State and the autonomous regions. That regulation also led to the birth of the national research plan as an "instrument for financing science". It also meant that public research organizations could create companies, as a solution to the lack of companies that encouraged new technologies and the disconnection of the science-technology system with the productive system.
Science, Technology and Innovation Law (2011)
It is regulated by Law 14/2011, of 1 June 2011, on "Science, Technology and Innovation", which entered into force six months after its publication. According to the Ninth Final Provision of the Law, some of its provisions have the character of basic legislation. This provides a mechanism for national, regional and corporative entities to cooperate and optimise their resources.
Article 21 of the Law contemplates the pre-doctoral contract.
Science Law 2022
In 2020, the Ministry published the prior consultation on the reform of the Science Law. Through the 2021 Budget Law, the legal figure of the state agency was reintroduced for the State Research Agency (AEI) and the Spanish National Research Council (CSIC), which had been transformed into an autonomous body in 2015. State agencies have greater independence for the management of their budget. A new Science Law is expected to be approved in 2022.
Sources of funding
In 2020, Spain will invest 1.24% of its GDP in scientific research, well below the European average of 2.12%.
Strategic plans
Up to 2020, eight editions of the National R&D&I Plan have been published, covering the period from 1988 to 1991 to 2007–2020, currently in force.
Each year a Work Program of the National R&D&I Plan is approved, which serves as a short-term programming tool, and is managed by the Ministries of Science and Innovation (MICINN); Industry, Tourism and Trade; Education (MEFP); and Environment, Rural and Marine Affairs (MARM).
At the end of 2020 the Spanish Government officially presented its Digital Plan 2025 which focussed on the recovery, transformation and resilience of scientific endeavour as a significant contributor to the Spanish economy. The Minister of Digital Development Carme Artigas has announced that starting from late 2022 the country proposes to set up a secure environment where a wide range of companies will be able to test their risky AI systems for socially sensitive areas such as law enforcement, medical diagnostics or educational intervention. The rules proposed by the European Commission in 2021 will be applied with strict oversight in compliance with Spain's National Artificial Intelligence Strategy (ENIA).
"Nanoinventum" is a project led by the University of Barcelona to incorporate science and nanotechnology principles into elementary school level curriculums. The main objective is to help young people become familiar with scientific language and to cultivate a passion for nanotechnology and science in general.
Public Research Organizations
Public Research Organizations (OPI) carry out a large part of the R&D&I activities that are financed with public funds and usually manage some of the programs included in the National Plans.
The following OPI's are attached to the Ministry of Science and Innovation:
Spanish National Research Council (CSIC).
Center for Energy, Environmental and Technological Research (CIEMAT).
Geological and Mining Institute of Spain (IGME).
Spanish Institute of Oceanography (IEO).
National Institute of Agricultural and Food Research and Technology (INIA).
Institute of Astrophysics of the Canary Islands (IAC), in which the Government of the Canary Islands also participates.
The following OPI's are attached to other ministerial departments:
Hydrodynamic Experimental Channel of El Pardo (CEHIPAR).
Center for Sociological Research (CIS).
Centre for Political and Constitutional Studies (CEPC).
Center for Public Works Studies and Experimentation (CEDEX).
R&D Centers under the General Directorate of Armament and Material (DGAM) of the Ministry of Defense (MINISDEF).
Institute of Fiscal Studies (IEF).
Carlos III Health Institute (ISCIII).
National Geographic Institute (IGN).
National Institute for Research and Training on Drugs (INIFD).
State Meteorological Agency (AEMET).
National Institute of Aerospace Technology (INTA)
National Institute of Toxicology and Forensic Sciences (INTCF).
Within the national territory
The Advisory Committee for Singular Infrastructures (until 2006 called the Advisory Committee for Large Scientific Facilities, CAGIC) distinguishes between two types of Scientific and Technological Facilities: Large Scientific Facilities (GIC) and Medium Size Facilities (ITM). Their recognition as such is the responsibility of the Interministerial Commission for Science and Technology (CICYT).
Singular Scientific and Technical Infrastructures (ICTS)
Singular Scientific and Technical Infrastructure (ICTS) refers to a facility that is unique or exceptional in Spain, that requires a relatively high investment cost, and that its importance in research or development justifies its availability.
At present, the following facilities are recognized as Spanish ICTS (outdated list):
Spanish Antarctic Bases.
Oceanographic Research Vessel Hespérides.
Cornide de Saavedra Oceanographic Vessel.
Yebes Astronomical Center.
TJ-II Thermonuclear Fusion Device.
CISA High Biological Security Facility.
Singular Civil Engineering Installations of CEDEX.
CESGA FinisTerrae Supercomputer.
MareNostrum and MinoTauro supercomputers of the National Supercomputing Center.
Fine Chemical Plant of Catalonia.
Almeria Solar Platform.
Catalonia Computing and Communications Center.
RedIRIS.
Nuclear magnetic resonance laboratory of the Barcelona Science Park.
Clean Room of the National Microelectronics Center.
Technology Center of the Institute of Optoelectronic Systems of the Polytechnic University of Madrid.
Fauna and Flora Collections of the Museum of Natural Sciences and the Royal Botanical Garden.
ALBA Synchrotron Light Laboratory.
Oceanic Platform of the Canary Islands.
In addition, these are ICTS located in Spain, but with international participation:
Calar Alto Astronomical Center.
Teide Observatory.
Roque de los Muchachos Observatory.
Institut de radioastronomie millimétrique.
Gran Telescopio Canarias.
Medium Size Installations (MSI)
A Medium Size Installation is defined as an Installation that is unique in Spain, requiring an investment cost of between 3 and 8 million euros and a maintenance cost of more than half a million euros per year.
Outside the national territory, with Spanish participation
Spain participates in several international scientific programs and organizations. The benefit obtained from this participation is twofold: on the one hand, Spanish scientists can use the facilities for the development of their projects; on the other hand, the business network has the opportunity to make important business contracts.
Some of the facilities in which Spain participates are:
European Space Agency.
European Laboratory for Particle Physics.
European Molecular Biology Laboratory.
European Synchrotron Radiation Facility.
Institut Laue-Langevin.
ISIS, pulsed neutron and muon source.
CERN.
Scientific and technological fields
Spain was ranked 28th in the Global Innovation Index in 2024.
Physics
In 2020 Pablo Jarillo-Herrero was awarded the Wolf Prize in Physics, considered the prelude to the Nobel Prize. In 2009 Juan Ignacio Cirac was nominated for the same prestigious award for his research in quantum computing and quantum optics.
Chemistry
Among the Spanish contributions to chemistry are the research of Francisco Mojica that led to the birth of the CRISPR gene editing technique, a term he personally coined. Mariano Barbacid is one of the most internationally recognized biochemists, among his contributions is that he managed to isolate the human H-ras oncogene in bladder carcinoma. This was an incredible breakthrough in the study of the molecular basis of cancer. He currently directs the Spanish National Cancer Research Centre (CNIO).
Mathematics
In 2020, Spain ranked seventh in the world in terms of scientific impact in Mathematics. Internationally, centers such as the Institute of Mathematical Sciences (ICMAT), founded in 2007, and the Basque Center for Applied Mathematics (BCAM), founded in 2008, stand out. Carlos Beltrán solved Smale's Problem number 17, finding a probabilistic algorithm with polynomial complexity, and published his solution in 2009.
Medicine
Michael Servetus described in the 16th century the pulmonary circulation of the blood. Francisco Romero in 1801 performed the first heart operation.
Spain has a Nobel Prize in Medicine, Santiago Ramón y Cajal (1906), pioneer in the description of the functioning of the nervous system. Others were on the verge of being nominated, such as Jaime Ferrán y Clúa, discoverer of the cholera vaccine, which put an end to the epidemic that devastated Spain in the 19th century. He would later develop vaccines for tetanus, typhoid, tuberculosis and rabies. Also nominated were José Gómez Ocaña and August Pi i Sunyer. In the 19th century, the Balmis Expedition was the first international health expedition in history, with the aim of bringing the smallpox vaccine to all continents, a disease that was causing thousands of deaths of children worldwide. In 1921, surgeon Fidel Pagés developed the epidural anesthesia technique. The engineer Manuel Jalón Corominas invented the disposable hypodermic needle. Today Pedro Cavadas is internationally recognized for his milestones in transplant surgery.
Engineering
The galleon, a Spanish invention, enabled the birth of the Spanish Empire and its conquest of the seas. Narcís Monturiol, inventor of air-independent propulsion, and Isaac Peral were among the creators of the submarine. Juan de la Cierva invented the articulated rotor and the autogyro, precursor of the helicopter. In 1907, Leonardo Torres Quevedo (1852–1936) started up the world's first aerial lift for passengers on Mount Ulía in San Sebastián.
Biology and biotechnology
In the biotechnology sector, institutions such as the National Biotechnology Center, companies such as PharmaMar and Zendal and researchers such as Mariano Esteban stand out.
Nuclear energy
Spain currently has generation II nuclear reactors, with the most advanced countries developing the generation IV reactor. It can be said that the father of nuclear energy in Spain was José María Otero de Navascués. Today the Center for Energy, Environmental and Technological Research (CIEMAT) is the main Spanish research center in this area, which has the TJ-II stellarator, and is planning a successor, the TJ-III. Pablo Rodríguez Fernández is a leading researcher in the race for nuclear fusion. Granada is a candidate to host IFMIF-DONES from 2030 onwards.
Computer science
Hardware and electronics
Ramón Verea (1833–1899) created the first mechanical calculator capable of direct multiplication.
Leonardo Torres Quevedo (1852–1936) created moderm wireless remote-control operation principles and analog calculating machines that could solve algebraic equations. In 1912, he built an automaton for playing chess endgames, El Ajedrecista, which has been considered the first computer game in history. He also introduced the idea of floating-point arithmetic to computers for the first time.
José García Santesmases (1907–1989) built the first analog computer and the first Spanish-made microprocessor. In 1967 he launched the Factor-P, the first computer manufactured in Spain.
In 2016 and 2017 BQ became the third best-selling smartphone brand in Spain, with phones designed in the country. Towards the end of the 1990s and early 2000s several companies manufactured laptops in Spain, most notably Airis and Inves. By 2021, Primux, Slimbook, Vant and Mountain already designed and assembled their computers in Spain.
Between 1987 and 2009 there was a large microchip factory in Tres Cantos, but it closed due to the difficulty of competing with the Asian market. Currently there are Spanish companies with microchip production capacity on a smaller scale, but which also have design capacity, such as Televés, a pioneer in Europe in the use of DIE electronic components (electronic components without encapsulation) and which also has the capacity to manufacture MMIC circuits, Ikor, and Anafocus, dedicated to the manufacture of CMOS image sensors.
Software
Between 1983 and 1992, Spain became one of the largest producers of video games, in what is called the golden age of the Spanish video game. Today FX Interactive, heir of Dinamic Software, is among the most prominent companies.
Internet
At the end of the 1990s IRC-Hispano was the reference as a social community in the Hispanic world. Other software companies that have achieved great repercussion are the search engine Olé, Terra Networks or Tuenti. Today, Wallapop, Fotocasa, Cabify and Rakuten TV stand out.
Space
The evolution of astronomical navigation, thanks to the contributions of astronomers such as Alonso de Santa Cruz, Juan Arias de Loyola and Jorge Juan y Santacilia was also key to Spain's preponderance in the oceans.
Since 1968 the National Institute for Aerospace Technology has concatenated scientific satellite programs, starting with the Intasat Program, continuing with the Minisat program which was a qualitative leap in the 90's, and continuing up to the current Small Satellite Constellation Program. Many of the instruments used in space missions to Mars and asteroids are developed at the Astrobiology Center (CAB). Among the major contributors in the space area are Emilio Herrera, inventor of the stratonautical space suit, predecessor of the space suit; Enrique Trillas, promoter of space science programs; and Pedro Duque, the first Spanish astronaut.
Science and Technology Parks
In Spain there are many science and technology parks, all of them are usually grouped in the Association of Science and Technology Parks of Spain (APTE).
Espaitec. Universitat Jaume I Science, Technology and Business Park.
Alava Technology Park.
Science and Technology Park of Castilla-La Mancha in Albacete.
Science and Technology Park of Alcalá.
Science and Technology Park of Jaén (Geolit).
Mediterranean Science Park in Alicante.
Asturias Technology Park.
Balearic Technological Innovation Park.
Barcelona Science Park.
22@Barcelona.
Bizkaia Technology Park – Zamudio.
Center for Technological Development of the University of Cantabria.
Castilla y León Technology Parks.
Galicia Technology Park.
Gijon Science and Technology Park.
Granada Health Sciences Technological Park.
Carlos III University Leganés Technological Science Park.
Madrid Science Park.
Andalusia Technology Park (PTA) in Malaga.
Walqa Technology Park in Huesca.
La Salle Innovation Park.
San Sebastian Technology Park.
Cartuja 93 Science and Technology Park in Seville.
València Technology Park.
Polytechnic City of Innovation.
Vallés Technology Park.
Vigo Technology and Logistics Park.
Science and Technology Park of Cantabria (PCTCAN)
ICT City in A Coruña.
Bases antárticas de España (Antarctic bases in Spain)
International Programs
The international R&D&I programs in which Spain participates are usually focused on the European area, and the most important are the following:
Framework Program, of the European Union for the promotion and support of R&D&I.
ERA Nets, articulated within the Framework Program, are actions to develop a European research area.
ESF Collaborative Research Programmes (EUROCORES), of the European Science Foundation (ESF).
European Science Foundation, a non-governmental association made up of 76 organizations from 29 European countries.
Science and Technology for Development (CYTED), Ibero-American program of science and technology for development.
European Cooperation in Science and Technology (COST), with the participation of 34 European countries.
EMBC/EMBO/EMBL, the European Molecular Biology Conference, Organization and Laboratory.
EUREKA Program, an initiative to support cooperative R&D in Europe, promoted in Spain by the PROFIT Program.
European Space Agency, European organization for cooperation in space research and technology. Spain participates in the scientific, shuttle, human spaceflight and microgravity, Earth observation, telecommunications, satellite navigation and Hispasat-related programs.
CERN, European organization for nuclear research.
ESRF, scientific cooperation at the European Synchrotron Radiation Facility.
Institut Laue-Langevin, experimental research on microscopic structures and material dynamics.
Global Biodiversity Information Facility, international program for the study of global biodiversity.
International Institute for Computer Science, an extension of the Department of Electrical Engineering and Computer Science at the University of California, of which Spain has been a member since 14 November 1998.
Integrated Ocean Drilling Program, an international marine research program.
International Arctic Science Committee (IASC) since 2009.
Popular science
The Spanish Foundation for Science and Technology (FECYT) is a public foundation under the Ministry of Science and Innovation, whose mission is to foster science and innovation, promoting their integration and approach to society. The National Museum of Science and Technology (MUNCYT) is dedicated to conservation and to popular science and technology. It has two sites, one in Alcobendas and the other in A Coruña.
See also
History of science and technology in Spain
Open access in Spain
Women in STEM fields
Spanish Inventions
Spanish Inventors
Ministry of Science and Innovation
External links
Ministry of Science and Innovation: Science and Technology (in Spanish).
References
21st century
Industrial automation
Industrial computing
Internet of things
Technology forecasting
Big data
Industrial Revolution
Fourth Industrial Revolution | Science and technology in Spain | [
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70,480,889 | https://en.wikipedia.org/wiki/Z-HIT | Z-HIT, also denoted as ZHIT, Z-HIT relationship, is a bidirectional mathematical transformation, connecting the two parts of a complex function, - i.e. its modulus and its phase. Z-HIT relations are somewhat similar to the Kramers–Kronig relations, where the real part can be computed from the imaginary part (or vice versa). In contrast to the Kramers–Kronig relations, in the Z-HIT the impedance modulus is computed from the course of the phase angle (or vice versa). The main practical advantage of Z-HIT relationships over Kramers–Kronig relationships is, that the Z-HIT integration limits do not require any extrapolation: instead, an integration over the experimentally available frequency range provides accurate data.
More specifically, the angular frequency (ω) boundaries for computing one component of the complex function from the other one using the Kramers-Kronig relations, are ω=0 and ω=∞; these boundaries require extrapolation procedures of the measured impedance spectra. Concerning the ZHIT however, the computing of the course of the impedance modulus from the course of the phase shift can be performed within the measured frequency range, without the need of extrapolation. This avoids complications which may arise from the fact that impedance spectra can only be measured in a limited frequency range. Therefore, the Z-HIT-algorithm allows for verification of the stationarity of the measured test object as well as calculating the impedance values using the phase data. The latter property becomes important when drift effects are present in the impedance spectra which had to be detected or even removed when analysing and/or interpreting the spectra.
Z-HIT relations find use in Dielectric spectroscopy and in Electrochemical Impedance Spectroscopy.
Motivation
An important application of Z-HIT is the examination of experimental impedance spectra for artifacts. The examination of EIS series measurements is often difficult due to the tendency of examined objects to undergo changes during the measurement. This may occur in many standard EIS applications such as the evaluation of fuel cells or batteries during discharge. Further examples include the investigation of light-sensitive systems under illumination (e.g. Photoelectrochemistry) or the analysis of water uptake of lacquers on metal surfaces (e.g. corrosion-protection).
A descriptive example for an unsteady system is a Lithium-ion battery. Under cyclization or discharging, the amount of charge in the battery changes over time. The change in charge is coupled with a chemical redox reaction, transferring to a change in concentrations of the involved substances. This violates the principles of stationarity and causality which are prerequisites for proper EIS measurements. In theory, this would exclude drift-affected samples from valid evaluation. Using the ZHIT-algorithm, these and similar artifacts can be recognized and spectra following causality can even be reconstructed, which are consistent with the Kramers–Kronig relations and thereby valid for analysis.
Mathematical Formulation
Z-HIT is a special case of the Hilbert transform and through restriction by the Kramers–Kronig relations it can be derived for one-Port-systems. The frequency-dependent relationship between impedance and phase angle can be observed in the Bode plot of an impedance spectrum. Equation (1) is obtained as a general solution of the correlation between impedance modulus and phase shift.
Equation (1) indicates that the logarithm of the impedance () at a specific frequency can be calculated up to a constant value of (), if the phase shift is integrated up to the frequency point of interest , while the starting value of the integral can be freely chosen. As an additional contribution to the calculation of , the odd-numbered derivatives of the phase shift at the point have to be added, weighted with the factors .
The factors can be calculated according to equation (2), whereat represents the Riemann ζ-function.
The practically applied Z-HIT approximation is obtained from equation (1) by limitation to the first derivative of the phase shift neglecting higher derivatives (equation (3)), where C represents a constant.
The free choice of the integration boundaries in the ZHIT algorithm is a fundamental difference concerning the Kramers-Kronig relations; in ZHIT the integration boundaries are
and .
The greatest advantage of the ZHIT results from the fact, that both integration boundaries can be chosen within the measured spectrum, and thus does not require extrapolation to frequencies 0 and , as with the Kramers-Kronig relations.
Practical implementation
The practical implementation of the Z-HIT approximation is shown schematically in Figure 1. A continuous curve (spline) for each of the two independent measured quantities (impedance and phase) is created by smoothing (part 1 in Figure (1)) from the measured data points. With the help of the spline for the phase shift, values for the impedance are now calculated. First, the integral of the phase shift is calculated up to the corresponding frequency , where (if suited) the highest measured frequency is selected as starting point for the integration - c.f. part 2 in Figure (1). From the spline of the phase shift, its slope can be calculated at (part 3 in figure (1)). Thereby, a reconstructed curve of the impedance is obtained which is (in the ideal case) only shifted parallelly with regard to the measured curve. There exist several possibilities to determine the constant C in the Z-HIT equation (part 4 in Figure (1)), one of which contains a parallel shift of the reconstructed impedance in a frequency range not affected by artifacts (see notes). This shift is performed by a linear regression procedure. Comparing the resulting reconstructed impedance curve to the measured data (or the Splines of the impedance), artifacts can easily be detected. These are usually located in the high frequency range (caused by induction or mutual induction, especially when low impedance systems are investigated) or in the low frequency range (caused by the change of the system during the measurement (=drift)).
Notes (time requirements during measurement)
The measurement time required for a single impedance measurement point strongly depends on the frequency of interest. While frequencies above about 1 Hz can be measured within seconds, the measurement time increases significantly in the lower frequency range. Although the exact duration for measuring a complete impedance spectrum depends on the measuring device as well as on internal settings, the following measurement times can be considered as rules of thumb when measuring the frequency measurement points sequentially, with the upper frequency assumed as 100 kHz or 1 MHz:
Down to approx. 1 Hz, the measuring time is approx. 1 minute
Down to 0.1 Hz approx. 5 minutes
Down to 0.05 Hz approx. 10 minutes
Down to 0.02 Hz approx. 15 minutes
Down to 0.01 Hz approx. 30 minutes
Measurements down to or below 0.01 Hz are typically associated with measurement times in the range of several hours. Therefore, a spectrum can be roughly divided into three sub-ranges with regard to the occurrence of artifacts: in the high-frequency domain (approx. > 100 to 1000 Hz), induction or mutual induction can dominate. In the low frequency region (< 1 Hz), drift can occur due to noticeable change in the system. The range between about 1 Hz and 1000 Hz is usually not affected by high- or low-frequency artifacts. However, the mains frequency (50/60 Hz) may come into play as distorting artifact in this region.
Notes (application procedure)
In addition to the reconstruction of the impedance from the phase shift, the reverse approach is also possible. However, the herein presented procedure possesses several advantages:
When calculating the phase shift from the impedance, a function of the angular frequency ω comes into play which is more difficult to determine compared to the constant C in equation (3).
Generally, the phase shift is more stable than the impedance. This is based on the fact that for impedance elements (more precisely: Constant phase element, CPE ) the property "phase shift" remains constant even if the value of the impedance drastically changes. Such Constant Phase-elements are the typical electronic elements, among others such as the electrical resistor, capacitor and coil. For illustration, Figure 2 shows the impedance spectrum of an NTC resistor heated during the measurement (starting between 1 kHz and 10 kHz down to lower frequencies). It can clearly be seen that the value of the impedance (red curve) changes with temperature, while the phase shift (blue curve) remains constant. In other words, "a resistor remains a resistor".
The reconstruction of the impedance from the phase shift further restores the "inner (= complex)" relationship between these two quantities. This relationship is lost by the independent construction of the supporting point splines for impedance and phase (Figure 1). Depending on the system under investigation, this restored correlation - even in the absence of artifacts - can lead to an improved evaluation of the spectra. In such cases, the gain in accuracy due to the reconstruction of the complex impedance outweighs the approximation error according to equation (3), which results from the neglection of the higher derivatives.
Applications
Figure 3 shows an impedance spectrum of a measurement series of a painted steel sample during water uptake (upper part in Figure 3). The symbols in the diagram represent the interpolation points (nodes) of the measurement, while the solid lines represent the theoretical values simulated according to an appropriate model. The interpolation points for the impedance were obtained by the Z-HIT reconstruction of the phase shift. The bottom part of Figure 3 depicts the normalized error (ZZHIT − Zsmooth)/ZZHIT·100 of the impedance. For the error calculation, two different procedures are used to determine the "extrapolated impedance values":
the "extrapolated impedance values" can be calculated from the "splined (=Zsmooth)" data of the impedance (magenta)
the impedance values (blue) can be reconstructed by the Z-HIT (= ZZ-HIT) using the spline of the phase shift
The simulation according to the appropriate model is performed using the two different impedance curves. The corresponding residuals are calculated and depicted in the bottom part of the diagram in Figure (3).
Note: Error patterns as shown in the magenta bottom diagram in Figure (3) may be the motivation to extend an existing model by additional elements to minimize the fitting error. However, this is not possible in every case. The drift in the impedance spectrum mainly influences the low-frequency part by means of a changing system during the measurement. The spectrum in Figure 3 is caused by water penetrating into the pores of the lacquer, which reduces the impedance (resistance) of the coating. Therefore, the system behaves as if at each low-frequency measurement point the resistance of the coating was replaced by a further, smaller resistance due to the water uptake. However, there is no impedance element that exhibits such behavior. Therefore, any extension of the model would only result in a "smearing" of the error over a wider frequency range without reducing the error itself. Only the removal of the drift by reconstructing the impedance using Z-HIT leads to a significantly better compatibility between measurement and model.
Figure 4 shows a Bode plot of an impedance series measurement, performed on a fuel cell where the hydrogen of the fuel gas was deliberately poisoned by the addition of carbon monoxide. Due to the poisoning, active centers of the platinum catalyst are blocked, which severely impairs the performance of the fuel cell. Thereby, the blocking of the catalyst is depending on the potential, resulting in an alternating sorption and desorption of the carbon monoxide on the catalyst surface within the cell. This cyclical change of the active catalyst surface translates to pseudo-inductive behavior, which can be observed in the impedance spectrum of Figure 4 at low frequencies (< 3 Hz). The impedance curve was reconstructed by Z-HIT and is represented by the purple line, while the originally measured values are represented by the blue circles. The deviation in the low frequency part of the measurement can be clearly observed. Evaluation of the spectra shows significantly better agreement between model and measurement if the reconstructed Z-HIT impedances are used instead of the original data.
References
Original work:
W. Ehm, R. Kaus, C. A. Schiller, W. Strunz: Z-HIT — A Simple Relation Between Impedance Modulus and Phase Angle. Providing a New Way to the Validation of Electrochemical Impedance Spectra. In: F. Mansfeld, F. Huet, O. R. Mattos (Hrsg.): New Trends in Electrochemical Impedance Spectroscopy and Electrochemical Noise Analysis. Electrochemical Society Inc., Pennington, NJ, 2001, vol. 2000-24, , S. 1–10.
Andrzej Lasia: Z-HIT Transform. In:Electrochemical Impedance Spectroscopy and its Application. Springer New York Heidelberg Dordrecht London, 2014, , S. 299.
References
Electrochemistry | Z-HIT | [
"Chemistry"
] | 2,732 | [
"Electrochemistry"
] |
58,013,135 | https://en.wikipedia.org/wiki/International%20Journal%20of%20Occupational%20and%20Environmental%20Health | The International Journal of Occupational and Environmental Health was a quarterly peer-reviewed public health journal with a focus on occupational and environmental health. It was established in 1995 and was published by Routledge. The last editor-in-chief was Andrew Maier (University of Cincinnati).
History
The journal was established in 1995, and was originally published by Maney Publishing. Its founding editor-in-chief was Joseph LaDou (University of California, San Francisco), who initially spent between $50,000 and $75,000 of his own money each year to keep publishing the journal. David Egilman (Brown University) replaced LaDou as the journal's editor-in-chief in 2007. As of 2009, it was the official journal of the International Commission on Occupational Health. Along with the rest of Maney's portfolio, the journal was acquired by Taylor & Francis in 2015, which will stop publishing it at the end of 2018.
Recognition
A 2000 article in Occupational and Environmental Medicine identified the International Journal of Occupational and Environmental Health as one of the eight most prominent journals in the occupational health field. Epidemiologist David Michaels told ProPublica in 2017 that the journal was one of the few publications where "scientists whose work is independent of the corporations that manufacture chemicals" could publish their research, adding, "The silencing of that voice would be a real loss to the field."
Editorial board controversy
Shortly after acquiring the journal in 2015, Taylor & Francis angered the editorial board by appointing Andrew Maier as the journal's new editor-in-chief without consulting the board. In an April 2017 letter to Taylor & Francis, the board's 22 members called attention to their concerns about some of the publisher's recent practices. The editors stated in the letter that, had they been consulted, they probably would not have approved of Maier's appointment, citing the tendency of his research to reach conclusions favorable to entities with conflicts of interest in the topic. The editorial board members also criticized Taylor & Francis for retracting a paper by Egilman with no explanation. The following month, Taylor & Francis managing director Ian Bannerman responded to the letter, claiming that he had consulted editorial board member Jukka Takala before offering Maier the position of editor-in-chief. Takala, who had signed the original letter, told Retraction Watch that, in fact, he had not been contacted prior to Maier's appointment.
In November 2017, the editorial board sent a letter to the National Library of Medicine asking for the journal to be removed from MEDLINE. Later that month, the entire board resigned in protest. In their letter sent to Bannerman, the editors cited Taylor & Francis' appointment of Maier as editor-in-chief, as well as the company's unexplained retraction of Egilman's paper, as among the reasons for their resignation.
Abstracting and indexing
The journal is abstracted and indexed in:
According to the Journal Citation Reports, the journal has a 2017 impact factor of 1.195.
References
External links
Occupational safety and health journals
Environmental health journals
Routledge academic journals
Quarterly journals
Academic journals established in 1995
English-language journals
Publications disestablished in 2018 | International Journal of Occupational and Environmental Health | [
"Environmental_science"
] | 657 | [
"Environmental science journals",
"Environmental health journals"
] |
58,013,244 | https://en.wikipedia.org/wiki/Lecirelin | Lecirelin, sold under the brand names Dalmarelin, Ovucron, and Reproreline, is a short-acting gonadotropin-releasing hormone agonist (GnRH agonist) medication which is used in veterinary medicine in Europe and Israel. It is a GnRH analogue and a synthetic peptide, specifically a nonapeptide. The drug was introduced for veterinary use by 2000. It is used in form of the acetate salt.
See also
Gonadotropin-releasing hormone receptor § Agonists
References
GnRH agonists
Nonapeptides
Veterinary drugs | Lecirelin | [
"Chemistry"
] | 129 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
58,013,357 | https://en.wikipedia.org/wiki/Peforelin | Peforelin (), or peforelin acetate, sold under the brand name Maprelin, is a gonadotropin-releasing hormone agonist (GnRH agonist) medication which is used in veterinary medicine in Europe and Canada. It is a GnRH analogue and a synthetic peptide, specifically a decapeptide. The drug was introduced for veterinary use by 2001.
See also
Gonadotropin-releasing hormone receptor § Agonists
References
GnRH agonists
Decapeptides
Veterinary drugs | Peforelin | [
"Chemistry"
] | 112 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
58,013,772 | https://en.wikipedia.org/wiki/CBRP | CBRP, or Cluster Based Routing Protocol, is a routing protocol for wireless mesh networks. CBRP was originally designed in mid 1998 by the National University of Singapore and subsequently published as an Internet Draft in August 1998. CBRP is one of the earlier hierarchical ad-hoc routing protocols. In CBRP, nodes dynamically form clusters to maintain structural routing support and to minimize excessive discovery traffic typical for ad-hoc routing.
Many performance studies on CBRP have been conducted in the area of Vehicular Ad-Hoc Network (VANET). CBRP is shown to perform moderately well in large and high density mesh networks
See also
Wireless ad hoc networks
Mesh networking
List of Ad Hoc Routing Protocols
References
Ad hoc routing protocols
Mesh networking | CBRP | [
"Technology"
] | 147 | [
"Computing stubs",
"Wireless networking",
"Mesh networking",
"Computer network stubs"
] |
58,014,671 | https://en.wikipedia.org/wiki/Zhihong%20Xia | Zhihong "Jeff" Xia (; born 20 September 1962, in Dongtai, Jiangsu, China) is a Chinese-American mathematician.
Education and career
Xia received, in 1982, from Nanjing University a bachelor's degree in astronomy and in 1988, a PhD in mathematics from Northwestern University with thesis advisor Donald G. Saari, for his thesis, The Existence of the Non-Collision Singularities. From 1988 to 1990, Xia was an assistant professor at Harvard University and from 1990 to 1994, an associate professor at Georgia Institute of Technology (and Institute Fellow). In 1994, he became a full professor at Northwestern University and since 2000, he has been the Arthur and Gladys Pancoe Professor of Mathematics.
His research deals with celestial mechanics, dynamical systems, Hamiltonian dynamics, and ergodic theory. In his dissertation, he solved the Painlevé conjecture, a long-standing problem posed in 1895 by Paul Painlevé. The problem concerns the existence of singularities of non-collision character in the -body problem in three-dimensional space; Xia proved the existence for . For the existence proof, he constructed an example of five masses, of which four are separated into two pairs which revolve around each other in eccentric elliptical orbits about the z-axis of symmetry, and a fifth mass moves along the z-axis. For selected initial conditions, the fifth mass can be accelerated to an infinite velocity in a finite time interval (without any collision between the bodies involved in the example). The case was open until 2014, when it was solved by Jinxin Xue. For , Painlevé had proven that the singularities (points of the orbit in which accelerations become infinite in a finite time interval) must be of the collision type. However, Painlevé's proof did not extend to the case .
In 1993, Xia was the inaugural winner of the Blumenthal Award of the American Mathematical Society. From 1989 to 1991, he was a Sloan Fellow. From 1993 to 1998, he received the National Young Investigator Award from the National Science Foundation. In 1995, he received the Monroe H. Martin Prize in Applied Mathematics from the University of Maryland. In 1998, he was an Invited Speaker of the International Congress of Mathematicians in Berlin.
Selected publications
References
20th-century Chinese mathematicians
21st-century Chinese mathematicians
Mathematicians from Jiangsu
20th-century American mathematicians
21st-century American mathematicians
Dynamical systems theorists
Nanjing University alumni
Northwestern University alumni
Northwestern University faculty
1962 births
Living people
People from Dongtai
Educators from Yancheng
Chinese emigrants to the United States | Zhihong Xia | [
"Mathematics"
] | 522 | [
"Dynamical systems theorists",
"Dynamical systems"
] |
58,015,117 | https://en.wikipedia.org/wiki/Russian%20Sleep%20Experiment | The Russian Sleep Experiment is a creepypasta which tells the tale of 5 Soviet-era test subjects being exposed to an experimental sleep-inhibiting stimulant, and has become the basis of an urban legend. Many news organizations, including Snopes, News.com.au, and LiveAbout, trace the story's origins to a website, now known as the Creepypasta Wiki, being posted on August 10, 2010, by a user named OrangeSoda, whose real name is unknown.
Plot
The story recounts an experiment set in 1947 at a covert Soviet test facility, where scientists give test subjects a stimulant gas that would prevent sleep. As the experiment progresses, it is shown that the lack of sleep transforms the subjects into violent zombie-like creatures who are addicted to the gas. At the end of the story, every character dies except one scientist.
Popularity and reception
The Russian Sleep Experiment became immensely popular upon its original publication. It is considered by some to be the greatest and most shared creepypasta story ever made and Dread Central's Josh Millican has called it "one of the most shocking and impactful urban legends of the Internet Age". Much of the online and offline debate surrounds the belief held by many that the story is real rather than fiction, and many articles therefore seek to debunk this claim.
The creepypasta is often shared alongside an image of a grotesque, emaciated figure, which is implied to be one of the test subjects. The image is actually of a life-size animatronic Halloween prop called "Spazm".
Literary criticism
In the chapter "Horror Memes and Digital Culture" in The Palgrave Handbook of Contemporary Gothic, Tosha R. Taylor wrote that the creepypasta "reflects residual political anxieties as it purports to reveal a top-secret effort by Russian scientists in World War II."
Sonali Srivastav and Shikha Rai drew comparisons between "Russian Sleep Experiment" and the 2018 miniseries Ghoul, noting that the series took inspiration from the creepypasta.
Adaptations
The Russian Sleep Experiment's popularity has led to various adaptations over the years. A novel inspired by the original short story was published in 2015 but is now out-of-print.
The 2019 play Subject UH1317 - When Science Traces A Deadly Turn is based on the short story.
In early 2018, a psychological thriller based on the short story began production in Ireland, directed by John Farrelly. The film was subsequently released in November 2022.
In July 2019, horror author Jeremy Bates published The Sleep Experiment, a novel closely based on the original short story.
Several other adaptations have been created, including a film based on the short story entitled The Soviet Sleep Experiment, with Chris Kattan starring and Barry Andersson directing. Filming for the movie took place in Lakeville, Minnesota during 2018.
References
External links
The Russian Sleep Experiment on creepypasta.com
Fiction about cannibalism
Creepypasta
Fakelore
Fiction set in the 1940s
Horror short stories
Human experimentation in fiction
Internet memes introduced in 2010
Soviet Union in fiction
Urban legends
Sleeplessness and sleep deprivation
2010 short stories | Russian Sleep Experiment | [
"Biology"
] | 648 | [
"Behavior",
"Sleep",
"Sleeplessness and sleep deprivation"
] |
58,017,210 | https://en.wikipedia.org/wiki/NGC%203861 | NGC 3861 is a large barred spiral galaxy with a ring-like structure located about 310 million light-years away in the constellation Leo. It was discovered by astronomer John Herschel on March 23, 1827. NGC 3861 is a member of the Leo Cluster and has a normal amount of neutral hydrogen (H I) and ionised hydrogen (H II).
NGC 3861 is a low luminosity type II Seyfert galaxy. However, it is also classified as a LINER galaxy.
On March 7, 2014, a type Ia supernova designated as SN 2014aa was discovered in NGC 3861.
References
External links
Barred spiral galaxies
Seyfert galaxies
LINER galaxies
Overlapping galaxies
Leo Cluster
Leo (constellation)
3861
Astronomical objects discovered in 1827
36604
6724
Discoveries by John Herschel | NGC 3861 | [
"Astronomy"
] | 170 | [
"Leo (constellation)",
"Constellations"
] |
58,017,976 | https://en.wikipedia.org/wiki/Asteroid%20impact%20prediction | Asteroid impact prediction is the prediction of the dates and times of asteroids impacting Earth, along with the locations and severities of the impacts.
The process of impact prediction follows three major steps:
Discovery of an asteroid and initial assessment of its orbit which is generally based on a short observation arc of less than 2 weeks.
Follow-up observations to improve the orbit determination
Calculating if, when and where the orbit may intersect with Earth at some point in the future.
The usual purpose of predicting an impact is to direct an appropriate response.
Most asteroids are discovered by a camera on a telescope with a wide field of view. Image differencing software compares a recent image with earlier ones of the same part of the sky, detecting objects that have moved, brightened, or appeared. Those systems usually obtain a few observations per night, which can be linked up into a very preliminary orbit determination. This predicts approximate positions over the next few nights, and follow-ups can then be carried out by any telescope powerful enough to see the newly detected object. Orbit intersection calculations are then carried out by two independent systems, one (Sentry) run by NASA and the other (NEODyS) by ESA.
Current systems only detect an arriving object when several factors are just right, mainly the direction of approach relative to the Sun, the weather, and phase of the Moon. The overall success rate is around 1% and is lower for the smaller objects. A few near misses by medium-size asteroids have been predicted years in advance, with a tiny chance of striking Earth, and a handful of small impactors have successfully been detected hours in advance. All of the latter struck wilderness or ocean, and hurt no one. The majority of impacts are by small, undiscovered objects. They rarely hit a populated area, but can cause widespread damage when they do. Performance is improving in detecting smaller objects as existing systems are upgraded and new ones come on line, but all current systems have a blind spot around the Sun that can only be overcome by a dedicated space based system or by discovering objects on a previous approach to Earth many years before a potential impact.
History
In 1992 a report to NASA recommended a coordinated survey (christened Spaceguard) to discover, verify and provide follow-up observations for Earth-crossing asteroids. This survey was scaled to discover 90% of all objects larger than one kilometer within 25 years. Three years later, a further NASA report recommended search surveys that would discover 60–70% of the short-period, near-Earth objects larger than one kilometer within ten years and obtain 90% completeness within five more years.
In 1998, NASA formally embraced the goal of finding and cataloging, by 2008, 90% of all near-Earth objects (NEOs) with diameters of 1 km or larger that could represent a collision risk to Earth. The 1 km diameter metric was chosen after considerable study indicated that an impact of an object smaller than 1 km could cause significant local or regional damage but is unlikely to cause a worldwide catastrophe. The impact of an object much larger than 1 km diameter could well result in worldwide damage up to, and potentially including, extinction of the human race. The NASA commitment has resulted in the funding of a number of NEO search efforts, which made considerable progress toward the 90% goal by the target date of 2008 and also produced the first ever successful prediction of an asteroid impact (the 4-meter was detected 19 hours before impact). However, the 2009 discovery of several NEOs approximately 2 to 3 kilometers in diameter (e.g. , , , and ) demonstrated there were still large objects to be detected.
Three years later, in 2012, the 40 meter diameter asteroid 367943 Duende was discovered and successfully predicted to be on close but non-colliding approach to Earth again just 11 months later. This was a landmark prediction as the object was only , and it was closely monitored as a result. On the day of its closest approach and by coincidence, a smaller asteroid was also approaching Earth, unpredicted and undetected, from a direction close to the Sun. Unlike 367943 Duende it was on a collision course and it impacted Earth 16 hours before 367943 Duende passed, becoming the Chelyabinsk meteor. It injured 1,500 people and damaged over 7,000 buildings, raising the profile of the dangers of even small asteroid impacts if they occur over populated areas. The asteroid is estimated to have been 17 m across.
In April 2018, the B612 Foundation stated "It's 100 per cent certain we'll be hit [by a devastating asteroid], but we're not 100 per cent sure when." Also in 2018, physicist Stephen Hawking, in his final book Brief Answers to the Big Questions, considered an asteroid collision to be the biggest threat to the planet. In June 2018, the US National Science and Technology Council warned that America is unprepared for an asteroid impact event, and has developed and released the National Near-Earth Object Preparedness Strategy Action Plan to better prepare.
Discovery of near-Earth asteroids
The first step in predicting impacts is detecting asteroids and determining their orbits. Finding faint near-Earth objects against the much more numerous background stars is very much a needle in a haystack search. It is achieved by sky surveys that are designed to discover near Earth asteroids. Unlike the majority of telescopes that have a narrow field of view and high magnification, survey telescopes have a wide field of view to scan the entire sky in a reasonable amount of time with enough sensitivity to pick up the faint near-Earth objects they are searching for.
NEO focused surveys revisit the same area of sky several times in succession. Movement can then be detected using image differencing techniques. Anything that moves from image to image against the background of stars is compared to a catalogue of all known objects, and if it is not already known is reported as a new discovery along with its precise position and the observation time. This then allows other observers to confirm and add to the data about the newly discovered object.
Cataloging vs warning surveys
Asteroid surveys can be broadly classified as either cataloging surveys, which use larger telescopes to mostly identify larger asteroids well before they come notably close to Earth, or warning surveys, which use smaller telescopes to mostly look for smaller asteroids within several million kilometers of Earth. Cataloging systems focus on finding larger asteroids years in advance and they scan the sky slowly (of the order of once per month), but deeply. Warning systems focus on scanning the sky relatively quickly (of the order of once per night). They typically cannot detect objects that are as faint as cataloging systems but they will not miss an asteroid that dramatically brightens for just a few days when it passes very close to Earth. Some systems compromise and scan the sky approximately once per week.
Cataloging systems
For larger asteroids (> 100 m to 1 km across), prediction is based on cataloging the asteroid, years to centuries before it could impact. This technique is possible as their size makes them bright enough to be seen from a long distance. Their orbits therefore can be measured and any future impacts predicted long before they are on an impact approach to Earth. This long period of warning is important as an impact from a 1 km object would cause worldwide damage and a minimum of around a decade of lead time would be needed to deflect it away from Earth. As of 2018, the inventory is nearly complete for the kilometer-size objects (around 900) which would cause global damage, and approximately one third complete for 140 meter objects (around 8500) which would cause major regional damage. The effectiveness of the cataloging is somewhat limited by the fact that some proportion of the objects have been lost since their discovery, due to insufficient observations to accurately determine their orbits.
Warning systems
Smaller near-Earth objects number into millions and therefore impact Earth much more often, though obviously with much less damage. The vast majority remain undiscovered. They seldom pass close enough to Earth that they become bright enough to observe, and so most can only be observed when within a few million kilometers of Earth. They therefore cannot usually be catalogued well in advance and can only be warned about, a few weeks to days in advance.
Current mechanisms for detecting asteroids on approach rely on ground based visible-light telescopes with wide fields of view. Those currently can monitor the sky at most every night, and therefore miss most of the smaller asteroids which are bright enough to detect for less than a day. Such very small asteroids much more commonly impact Earth than larger ones, but they make little damage. Missing them therefore has limited consequences. Much more importantly, ground-based telescopes are blind to most of the asteroids which impact the day side of the planet and will miss even large ones. These and other problems mean very few impacts are successfully predicted (see §Effectiveness of the current system and §Improving impact prediction).
Asteroids detected by warning systems are much too close to their time of potential impact to deflect them away from Earth, but there is still enough time to mitigate the consequences of the impact by evacuating and otherwise preparing the affected area. Warning systems can also detect asteroids which have been successfully catalogued as existing, but whose orbit was insufficiently well determined to allow a prediction of where they are now.
Surveys
The main NEO focussed surveys are listed below, along with future telescopes that are already funded.
Originally all the surveys were clustered together in a relatively small part of the Northern Hemisphere. This meant that around 15% of the sky at extreme Southern declination was never monitored, and that the rest of the Southern sky was observed over a shorter season than the Northern sky. Moreover, as the hours of darkness are fewer in summertime, the lack of a balance of surveys between North and South meant that the sky was scanned less often in the Northern summer. The ATLAS telescopes now operating at the South African Astronomical Observatory and El Sauce observatory in Chile now cover this gap in the south east of the globe. Once it is completed, the Large Synoptic Survey Telescope will improve the existing cover of the southern sky. The 3.5 m Space Surveillance Telescope, which was originally also in the southwest United States, was dismantled and moved to Western Australia in 2017. When completed, this should also improve the global coverage. Construction has been delayed due to the new site being in a cyclone region, but was completed in September 2022.
ATLAS
ATLAS, the "Asteroid Terrestrial-impact Last Alert System" uses four 0.5-metre telescopes. Two are located on the Hawaiian Islands, at Haleakala and Mauna Loa, one at the South African Astronomical Observatory, and one in Chile. With a field of view of 30 square degrees each, the telescopes survey the observable sky down to apparent magnitude 19 with 4 exposures every night. The survey has been operational with the two Hawaii telescopes since 2017, and in 2018 obtained NASA funding for two additional telescopes sited in the Southern hemisphere. They were expected to take 18 months to build. Their southern locations provide coverage of the 15% of the sky that cannot be observed from Hawaii, and combined with the Northern hemisphere telescopes give non-stop coverage of the equatorial night sky (the South African location is not only in the opposite hemisphere to Hawaii, but also at an opposing longitude). The full ATLAS concept consists of eight of its 50-centimeter diameter f/2 Wright-Schmidt telescopes, spread over the globe for 24h/24h coverage of the full-night-sky.
Catalina Sky Survey (including Mount Lemmon Survey)
In 1998, the Catalina Sky Survey (CSS) took over from Spacewatch in surveying the sky for the University of Arizona. It uses two telescopes, a 1.5 m Cassegrain reflector telescope on the peak of Mount Lemmon (also known as a survey in its own right, the Mount Lemmon Survey), and a 0.7 m Schmidt telescope near Mount Bigelow (both in the Tucson, Arizona area in the south west of the United States). Both sites use identical cameras which provide a field of view of 5 square degrees on the 1.5 m telescope and 19 square degrees on the Catalina Schmidt. The Cassegrain reflector telescope takes three to four weeks to survey the entire sky, detecting objects fainter than apparent magnitude 21.5. The 0.7 m telescope takes a week to complete a survey of the sky, detecting objects fainter than apparent magnitude 19. This combination of telescopes, one slow and one medium, has so far detected more near Earth Objects than any other single survey. This shows the need for a combination of different types of telescopes.
CSS used to include a telescope in the Southern Hemisphere, the Siding Spring Survey. However operations ended in 2013 after funding was discontinued.
Kiso Observatory (Tomo-e Gozen)
The Kiso Observatory uses a 1.05m Schmidt telescope on Mt. Ontake near Tokyo in Japan. In late 2019 the Kiso Observatory added a new instrument to the telescope, "Tomo-e Gozen", designed to detect fast moving and rapidly changing objects. It has a wide field of view (20 square degrees) and scans the sky in just 2 hours, far faster than any other survey as of 2021. This puts it squarely in the warning survey category. In order to scan the sky so quickly, the camera captures 2 frames per second, which means the sensitivity is lower than other metre class telescopes (which have much longer exposure times), giving a limiting magnitude of just 18. However, despite not being able to see dimmer objects which are detectable by other surveys, the ability to scan the entire sky several times per night allows it to spot fast moving asteroids that other surveys miss. It has discovered a significant number of near-Earth asteroids as a result (for example see List of asteroid close approaches to Earth in 2021).
Large Synoptic Survey Telescope
The Large Synoptic Survey Telescope (LSST) is a wide-field survey reflecting telescope with an 8.4 meter primary mirror, currently under construction on Cerro Pachón in Chile. It will survey the entire available sky around every three nights. Science operations are due to begin in 2022. Scanning the sky relatively fast but also being able to detect objects down to apparent magnitude 27, it should be good at detecting nearby fast moving objects as well as excellent for larger slower objects that are currently further away.
Near-Earth Object Surveillance Mission
A planned space-based 0.5m infrared telescope designed to survey the Solar System for potentially hazardous asteroids. The telescope will use a passive cooling system, and so unlike its predecessor NEOWISE, it will not suffer from a performance degradation due to running out of coolant. It does still have a limited mission duration however as it needs to use propellant for orbital station keeping in order to maintain its position at SEL1. From here, the mission will search for asteroids hidden from Earth based satellites by the Sun's glare. It is planned for launch in 2026.
NEO Survey Telescope
The Near Earth Object Survey TELescope (NEOSTEL) is an ESA funded project, starting with an initial prototype currently under construction. The telescope is of a new "fly-eye" design that combines a single reflector with multiple sets of optics and CCDs, giving a very wide field of view (around 45 square degrees). When complete it will have the widest field of view of any telescope and will be able to survey the majority of the visible sky in a single night. If the initial prototype is successful, three more telescopes are planned for installation around the globe. Because of the novel design, the size of the primary mirror is not directly comparable to more conventional telescopes, but is equivalent to a conventional 1–metre telescope.
The telescope itself should be complete by end of 2019, and installation on Mount Mufara, Sicily should be complete in 2020 but was pushed back to 2022.
NEOWISE
The Wide-field Infrared Survey Explorer is a 0.4 m infrared-wavelength space telescope launched in December 2009, and placed in hibernation in February 2011. It was re-activated in 2013 specifically to search for near-Earth objects under the NEOWISE mission. By this stage, the spacecraft's cryogenic coolant had been depleted and so only two of the spacecraft's four sensors could be used. Whilst this has still led to new discoveries of asteroids not previously seen from ground-based telescopes, the productivity has dropped significantly. In its peak year when all four sensors were operational, WISE made 2.28 million asteroid observations. In recent years, with no cryogen, NEOWISE typically makes approximately 0.15 million asteroid observations annually. The next generation of infrared space telescopes has been designed so that they do not need cryogenic cooling.
Pan-STARRS
Pan-STARRS, the "Panoramic Survey Telescope And Rapid Response System", currently (2018) consists of two 1.8 m Ritchey–Chrétien telescopes located at Haleakala in Hawaii. It has discovered a large number of new asteroids, comets, variable stars, supernovae and other celestial objects. Its primary mission is now to detect near-Earth objects that threaten impact events, and it is expected to create a database of all objects visible from Hawaii (three-quarters of the entire sky) down to apparent magnitude 24. The Pan-STARRS NEO survey searches all the sky north of declination −47.5. It takes three to four weeks to survey the entire sky.
Space Surveillance Telescope
The Space Surveillance Telescope (SST) is a 3.5 m telescope that detects, tracks, and can discern small, obscure objects, in deep space with a wide field of view system. The SST mount uses an advanced servo-control technology, that makes it one of the quickest and most agile telescopes of its size. It has a field of view of 6 square degrees and can scan the visible sky in 6 clear nights down to apparent magnitude 20.5. Its primary mission is tracking orbital debris. This task is similar to that of spotting near-Earth asteroids and so it is capable of both.
The SST was initially deployed for testing and evaluation at the White Sands Missile Range in New Mexico. On 6 December 2013, it was announced that the telescope system would be moved to the Naval Communication Station Harold E. Holt in Exmouth, Western Australia. The SST was moved to Australia in 2017, captured first light in 2020 and after a two and a half year testing programme became operational in September 2022.
Spacewatch
Spacewatch was an early sky survey focussed on finding near Earth asteroids, founded in 1980. It was the first to use CCD image sensors to search for them, and the first to develop software to detect moving objects automatically in real-time. This led to a huge increase in productivity. Before 1990 a few hundred observations were made each year. After automation, annual productivity jumped by a factor of 100 leading to tens of thousands of observations per year. This paved the way for the surveys we have today.
Although the survey is still in operation, in 1998 it was superseded by Catalina Sky Survey. Since then it has focused on following up on discoveries by other surveys, rather than making new discoveries itself. In particular it aims to prevent high priority PHOs from being lost after their discovery. The survey telescopes are 1.8 m and 0.9 m. The two follow-up telescopes are 2.3 m and 4 m.
Zwicky Transient Facility
The Zwicky Transient Facility (ZTF) was commissioned in 2018, superseding the Intermediate Palomar Transient Factory (2009–2017). It is designed to detect transient objects that rapidly change in brightness, for example supernovae, gamma ray bursts, collisions between two neutron stars, as well as moving objects such as comets and asteroids. The ZTF is a 1.2 m telescope that has a field of view of 47 square degrees, designed to image the entire northern sky in three nights and scan the plane of the Milky Way twice each night to a limiting magnitude of 20.5. The amount of data produced by ZTF is expected to be 10 times larger than its predecessor.
Follow-up observations
Once a new asteroid has been discovered and reported, other observers can confirm the finding and help define the orbit of the newly discovered object. The International Astronomical Union Minor Planet Center (MPC) acts as the global clearing house for information on asteroid orbits. It publishes lists of new discoveries that need verifying and still have uncertain orbits, and it collects the resulting follow-up observations from around the world. Unlike the initial discovery, which typically requires unusual and expensive wide-field telescopes, ordinary telescopes can be used to confirm the object as its position is now approximately known. There are far more of these around the globe, and even a well equipped amateur astronomer can contribute valuable follow-up observations of moderately bright asteroids. For example, the Great Shefford Observatory in the back garden of amateur Peter Birtwhistle typically submits thousands of observations to the Minor Planet Center every year. Nonetheless, some surveys (for example CSS and Spacewatch) have their own dedicated follow-up telescopes.
Follow-up observations are important because once a sky survey has reported a discovery it may not return to observe the object again for days or weeks. By this time it may be too faint for it to detect, and in danger of becoming a lost asteroid. The more observations and the longer the observation arc, the greater the accuracy of the orbit model. This is important for two reasons:
for imminent impacts it helps to make a better prediction of where the impact will occur and whether there is any danger of hitting a populated area.
for asteroids that will miss Earth this time round, the more accurate the orbit model is, the further into the future its position can be predicted. This allows recovery of the asteroid on its subsequent approaches, and impacts to be predicted years in advance.
Estimating size and impact severity
Assessing the size of the asteroid is important for predicting the severity of the impact, and therefore the actions that need to be taken (if any). With just observations of reflected visible light by a conventional telescope, the object could be anything from 50% to 200% of the estimated diameter, and therefore anything from one-eighth to eight times the estimated volume and mass. Because of this, one key follow-up observation is to measure the asteroid in the thermal infrared spectrum (long-wavelength infrared), using an infrared telescope. The amount of thermal radiation given off by an asteroid together with the amount of reflected visible light allows a much more accurate assessment of its size than just how bright it appears in the visible spectrum. Jointly using thermal infrared and visible measurements, a thermal model of the asteroid can estimate its size to within about 10% of the true size.
One example of such a follow-up observation was for 3671 Dionysus by UKIRT, the world's largest infrared telescope at the time (1997). A second example was the 2013 ESA Herschel Space Observatory follow-up observations of 99942 Apophis, which showed it was 20% larger and 75% more massive than previously estimated. However such follow-ups are rare. The size estimates of most near-Earth asteroids are based on visible light only.
If the object was discovered by an infrared survey telescope initially, then an accurate size estimate will become available with visible light follow-up, and infrared follow-up will not be needed. However, none of the ground-based survey telescopes listed above operate at thermal infrared wavelengths. The NEOWISE satellite had two thermal infrared sensors but they stopped working when the cryogen ran out. There are therefore currently no active thermal infrared sky surveys which are focused on discovering near-Earth objects. There are plans for a new space based thermal infrared survey telescope, Near-Earth Object Surveillance Mission, due to launch in 2025.
Impact calculation
Minimum orbit intersection distance
The minimum orbit intersection distance (MOID) between an asteroid and the Earth is the distance between the closest points of their orbits. This first check is a coarse measure that does not allow an impact prediction to be made, but is based solely on the orbit parameters and gives an initial measure of how close to Earth the asteroid could come. If the MOID is large then the two objects never come near each other. In this case, unless the orbit of the asteroid is perturbed so that the MOID is reduced at some point in the future, it will never impact Earth and can be ignored. However, if the MOID is small then it is necessary to carry out more detailed calculations to determine if an impact will happen in the future. Asteroids with a MOID of less than 0.05 AU and an absolute magnitude brighter than 22 are categorized as a potentially hazardous asteroid.
Projecting into the future
Once the initial orbit is known, the potential positions can be forecast years into the future and compared to the future position of Earth. If the distance between the asteroid and the centre of the Earth is less than Earth radius then a potential impact is predicted. To take account of the uncertainties in the orbit of the asteroid, many future projections are made (simulations) with slightly different parameters within the range of the uncertainty. This allows a percentage chance of impact to be estimated. For example, if 1,000 simulations are carried out and 73 result in an impact, then the prediction would be a 7.3% chance of impact.
NEODyS
NEODyS (Near Earth Objects Dynamic Site) is a European Space Agency service that provides information on near Earth objects. It is based on a continually and (almost) automatically maintained database of near Earth asteroid orbits. The site provides a number of services to the NEO community. The main service is an impact monitoring system (CLOMON2) of all near-Earth asteroids covering a period until the year 2100.
The NEODyS website includes a Risk Page where all NEOs with probabilities of hitting the Earth greater than 10−11 from now until 2100 are shown in a risk list. In the table of the risk list the NEOs are divided into:
"special", as was the case of (99942) Apophis
"observable", objects which are presently observable and which critically need a follow-up in order to improve their orbit
"possible recovery", objects which are not visible at present, but which are possible to recover in the near future
"lost", objects which have an absolute magnitude (H) brighter than 25 but which are virtually lost, their orbit being too uncertain; and
"small", objects with an absolute magnitude fainter than 25; even when those are "lost", they are considered too small to result in heavy damage on the ground (though the Chelyabinsk meteor would have been fainter than this).
Each object has its own impactor table (IT) which shows many parameters useful to determine the risk assessment.
Sentry prediction system
NASA's Sentry System continually scans the MPC catalog of known asteroids, analyzing their orbits for any possible future impacts. Like ESA's NEODyS, it gives a list of possible future impacts, along with the probability of each. It uses a slightly different algorithm to NEODyS, and so provides a useful cross-check and corroboration.
Currently, no impacts are predicted (the single highest probability impact currently listed is ~7 m asteroid , which is due to pass Earth in September 2095 with only a 10% predicted chance of impacting; its size is also small enough that any damage from an impact would be minimal).
Impact probability calculation pattern
The ellipses in the diagram on the right show the predicted position of an example asteroid at closest Earth approach. At first, with only a few asteroid observations, the error ellipse is very large and includes the Earth. The impact prediction probability is small because the Earth cover a small fraction of the large error ellipse. (Often times the error ellipse extends for tens if not hundreds of millions of km.) Further observations shrink the error ellipse. If it still includes the Earth, this raises the predicted impact probability, since the fixed-size Earth now covers a larger fraction of the smaller error region. Finally, yet more observations (often radar observations, or discovery of a previous sighting of the same asteroid on much older archival images) shrink the ellipse, usually revealing that the Earth is outside the smaller error region and the impact probability is then near zero. In rare cases, the Earth remains in the ever shrinking error ellipse and the impact probability then approaches one.
For asteroids that are on track to hit Earth, the predicted probability of impact never stops increasing as more observations are made. This initially very similar pattern makes it difficult to quickly differentiate between asteroids which will be millions of kilometres from Earth and those which will hit it. This in turn makes it difficult to decide when to raise an alarm as gaining more certainty takes time, which reduces the time available to react to a predicted impact. However raising the alarm too soon has the danger of causing a false alarm and creating a Boy Who Cried Wolf effect if the asteroid in fact misses Earth. NASA will raise an alert if an asteroid has a better than 1% chance of impacting.
In December 2004 when Apophis was estimated to have a 2.7% chance of impacting Earth on 13 April 2029, the uncertainty region for this asteroid had shrunk to 82,818 km.
Response to predicted impact
Once an impact has been predicted the potential severity needs to be assessed, and a response plan formed. Depending on the time to impact and the predicted severity this may be as simple as giving a warning to citizens. For example, although unpredicted, the 2013
impact at Chelyabinsk was spotted through the window by teacher Yulia Karbysheva. She thought it prudent to take precautionary measures by ordering her students to stay away from the room's windows and to perform a duck and cover maneuver. The teacher, who remained standing, was seriously lacerated when the blast arrived and window glass severed a tendon in one of her arms and left thigh, but none of her students, whom she ordered to hide under their desks, suffered lacerations. If the impact had been predicted and a warning had been given to the entire population, similar simple precautionary actions could have vastly reduced the number of injuries. Children who were in other classes were injured.
If a more severe impact is predicted, the response may require evacuation of the area, or with sufficient lead time available, an avoidance mission to repel the asteroid. According to expert testimony in the United States Congress in 2013, NASA would require at least five years of preparation before a mission to intercept an asteroid could be launched which was demonstrated by kinetically deflecting a minor planet moon, non-hazardous NEO Asteroid called Dimorphos with the help of the DART spacecraft. Following a ten-month journey to the Didymos system, the impactor collided with Dimorphos on 26 September 2022 at a speed of around . The collision successfully decreased Dimorphos's orbital period around Didymos by minutes.
Effectiveness of the current system
The effectiveness of the current system can be assessed a number of ways. The diagram below illustrates the number of successfully predicted impacts each year compared to the number of unpredicted asteroid impacts recorded by infrasound sensors designed to detect detonation of nuclear devices. It shows that the success rate is increasing over time, but that the vast majority are still missed.
One problem with assessing effectiveness this way is that the sensitivity of infrasound sensors extends to small asteroids, which generally do very little damage. The missed asteroids do tend to be small, and missing small asteroids is relatively unimportant. By contrast, missing a large day-side impacting asteroid is highly problematic, with the unpredicted mid-size Chelyabinsk meteor providing a mild real-life example. In order to assess the effectiveness for detecting the (rare) larger asteroids which do matter, a different approach is needed.
That effectiveness for larger asteroid can be assessed by looking at warning times for asteroids which did not impact Earth but came close. The below diagram for asteroids which came closer than the Moon shows how far in advance of closest approach they were first detected. Unlike asteroid impacts, where infrasound sensors provide ground truth, it is impossible to know for sure how many close approaches were undetected. Of the asteroids that were detected, the diagram shows that about half were not detected until after they had passed Earth. If they had been on course to impact Earth, they would not have been spotted before they hit, primarily because they approached from a direction close to the Sun. This includes larger asteroids such as 2018 AH, which approached from a direction close to the Sun and was detected 2 days after it had passed. It is estimated to be around 100 times more massive than the Chelyabinsk meteor.
The number of detections is increasing as more survey sites come on line (for example ATLAS in 2016 and ZTF in 2018), but approximately half of the detections are made after the asteroid passes the Earth. The below charts visualise the warning times of the close approaches listed in the above bargraph, by the size of the asteroid instead of by the year they occurred in. The sizes of the charts show the relative sizes of the asteroids to scale. This is based on the absolute magnitude of each asteroid, an approximate measure of size based on brightness. For comparison, the approximate size of a person is also shown.
Abs magnitude 30 and greater
(size of a person for comparison)
Abs magnitude 29–30
Absolute magnitude 28–29
Absolute magnitude 27–28
Absolute magnitude 26–27
(probable size of the Chelyabinsk meteor)
Absolute magnitude 25–26
Absolute magnitude less than 25 (largest)
As can be seen, the ability to predict larger asteroids has significantly improved since the early years of the 21st century, with some now being catalogued (predicted more than 1 year in advance), or having usable early warning times (greater than a week).
Based on the few successfully predicted asteroid impacts, the average time between initial detection and impact is currently around 9 hours. There is some delay between the initial observation of the asteroid, data submission, and the follow-up observations and calculations which lead to an impact prediction being made.
Improving impact prediction
In addition to the already-funded telescopes mentioned above, two separate approaches have been suggested by NASA to improve impact prediction. Both approaches focus on the first step in impact prediction (discovering near-Earth asteroids) as this is the largest weakness in the current system. The first approach uses more powerful ground-based telescopes similar to the LSST. Being ground-based, such telescopes will still only observe part of the sky around Earth. In particular, all ground-based telescopes have a large blind spot for any asteroids coming from the direction of the Sun. In addition, they are affected by weather conditions, airglow and the phase of the Moon.
To get around all of these issues, the second approach suggested is the use of space-based telescopes which can observe a much larger region of the sky around Earth. Although they still cannot point directly towards the Sun, they do not have the problem of blue sky to overcome and so can detect asteroids much closer in the sky to the Sun than ground-based telescopes. Unaffected by weather or airglow they can also operate 24 hours per day all year round. Finally, telescopes in outer space have the advantage of being able to use infrared sensors without the interference of the Earth's atmosphere. These sensors are better for detecting asteroids than optical sensors, and although there are some ground based infrared telescopes such as UKIRT, they are not designed for detecting asteroids. Space-based telescopes are more expensive, and tend to have a shorter lifespan, so Earth-based and space-based technologies complement each other to an extent. Although the majority of the IR spectrum is blocked by Earth's atmosphere, the very useful thermal (long-wavelength infrared) frequency band is not blocked (see gap at 10 μm in the diagram below). This allows for the possibility of ground based thermal imaging surveys designed for detecting near earth asteroids, though none are currently planned.
Opposition effect
There is a further issue that even telescopes in Earth orbit do not overcome (unless they operate in the thermal infrared spectrum). This is the issue of illumination. Asteroids go through phases similar to the lunar phases. Even though a telescope in orbit may have an unobstructed view of an object that is close in the sky to the Sun, it will still be looking at the dark side of the object. This is because the Sun is shining on the side facing away from the Earth, as is the case with the Moon when it is in a new moon phase. Because of this opposition effect, objects are far less bright in these phases than when fully illuminated, which makes them difficult to detect (see chart and diagram below).
This problem can be solved by the use of thermal infrared surveys (either ground based or space based). Ordinary telescopes depend on observing light reflected from the Sun, which is why the opposition effect occurs. Telescopes which detect thermal infrared light depend only on the temperature of the object. Its thermal glow can be detected from any angle, and is particularly useful for differentiating asteroids from the background stars, which have a different thermal signature.
This problem can also be solved without using thermal infrared, by positioning a space telescope away from Earth, closer to the Sun. The telescope can then look back towards Earth from the same direction as the Sun, and any asteroids closer to Earth than the telescope will then be in opposition, and much better illuminated. There is a point between the Earth and Sun where the gravities of the two bodies are perfectly in balance, called the Sun-Earth L1 Lagrange point (SEL1). It is approximately from Earth, about four times as far away as the Moon, and is ideally suited for placing such a space telescope. One problem with this position is Earth glare. Looking outward from SEL1, Earth itself is at full brightness, which prevents a telescope situated there from seeing that area of sky. Fortunately, this is the same area of sky that ground-based telescopes are best at spotting asteroids in, so the two complement each other.
Another possible position for a space telescope would be even closer to the Sun, for example in a Venus-like orbit. This would give a wider view of Earth orbit, but at a greater distance. Unlike a telescope at the SEL1 Lagrange point, it would not stay in sync with Earth but would orbit the Sun at a similar rate to Venus. Because of this, it would not often be in a position to provide any warning of asteroids shortly before impact, but it would be in a good position to catalog objects before they are on final approach, especially those which primarily orbit closer to the Sun. One issue with being as close to the Sun as Venus is that the craft may be too warm to use infrared wavelengths. A second issue would be communications. As the telescope will be a long way from Earth for most of the year (and even behind the Sun at some points) communication would often be slow and at times impossible, without expensive improvements to the Deep Space Network.
Solutions to problems: summary table
This table summarises which of the various problems encountered by current telescopes are solved by the various different solutions.
Near-Earth Object Surveyor
In 2017, NASA proposed a number of alternative solutions to detect 90% of near-Earth objects of size 140 m or larger over the next few decades. As the detection sensitivity drops off with size but does not cut off, this will also improve the detection rates for the smaller objects which impact Earth much more often. Several of the proposals use a combination of an improved ground-based telescope and a space-based telescope positioned at the SEL1 Lagrange point. A number of large ground based telescopes are already in the late stages of construction (see above). A space based mission situated at SEL1, NEO Surveyor has now also been funded. It is planned for launch in 2027.
List of successfully predicted asteroid impacts
Below is the list of all near-Earth objects which have or may have impacted the Earth and which were predicted beforehand. This list would also include any objects identified as having greater than 50% chance of impacting in the future, but no such future impacts are predicted at this time. As asteroid detection ability increases it is expected that prediction will become more successful in the future.
In addition to these objects, the meteoroid CNEOS20200918 was found in 2022 in archival ATLAS data, imaged 10 minutes before its 2020/09/18 impact. Although it technically could have been discovered before impact, it was only noticed in retrospect.
There are also a number of objects which have been observed in orbit which may have impacted shortly after being observed, but may not have. It is difficult to know the true number of these possible impactors as unconfirmed tracklets have a wide range of possible orbits, and only a portion of these are consistent with earth impact. One example is A106fgF, an object observed on January 22, 2018 with an observation arc of only 39 minutes.
See also
Earth-grazing fireball
List of asteroid close approaches to Earth
List of bolidesasteroids and meteoroids that impacted Earth
Notes
References
External links
Earth Impact Database
Earth Impact Effects Program
NASA JPL Predicted Close Approaches (including impacts)
Astronomical events
Impact events
Lists of asteroids
Near-Earth asteroids
Planetary defense | Asteroid impact prediction | [
"Astronomy"
] | 8,491 | [
"Astronomical events",
"Impact events"
] |
58,018,099 | https://en.wikipedia.org/wiki/NGC%204207 | NGC 4207 is a spiral galaxy located about 50 million light-years away in the constellation Virgo. The galaxy was discovered by astronomer Heinrich d'Arrest on March 23, 1865. NGC 4207 is a member of the Virgo Cluster.
See also
List of NGC objects (4001–5000)
References
External links
4207
39206
Virgo (constellation)
Virgo Cluster
Astronomical objects discovered in 1865
Spiral galaxies
7268 | NGC 4207 | [
"Astronomy"
] | 89 | [
"Virgo (constellation)",
"Constellations"
] |
58,018,541 | https://en.wikipedia.org/wiki/Azagly-nafarelin | Azagly-nafarelin, sold under the brand name Gonazon, is a gonadotropin-releasing hormone agonist (GnRH agonist) medication which is used in veterinary medicine in Europe. It is a GnRH analogue and a synthetic peptide, specifically a decapeptide. The medication has been approved in Europe as a solid silicone-based matrix implant for use as a contraceptive in animals such as male dogs, cats, and others, but is no longer or was never commercially available. The medication has also been used to treat benign prostatic hyperplasia in animals. In addition to its use in mammals, azagly-nafarelin has been approved for use in aquaculture fish, specifically to control ovulation in salmonids, and was the first GnRH agonist to be available for use in fish. It was introduced for use by 2005.
See also
Gonadotropin-releasing hormone receptor § Agonists
References
GnRH agonists
Hormonal contraception
Decapeptides
Veterinary drugs | Azagly-nafarelin | [
"Chemistry"
] | 221 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
58,018,667 | https://en.wikipedia.org/wiki/Woldemar%20Weyl | Woldemar Anatol Weyl (1901 – July 30, 1975) was a German-born scientist.
Weyl taught at the Kaiser Wilhelm Institute between 1932 and 1936, when he began traveling to the United States as a visiting professor at Pennsylvania State University. Due to the increasing influence of the Nazi Party, Weyl choose not to return to Germany and was offered full tenure at PSU in 1938. In 1960, Weyl and mathematician Haskell Curry were appointed to the first two Evan Pugh Professorships at Penn State. Weyl died in State College, Pennsylvania on July 30, 1975, aged 74.
References
1901 births
1975 deaths
Emigrants from Nazi Germany to the United States
20th-century American scientists
Glass engineering and science | Woldemar Weyl | [
"Materials_science",
"Engineering"
] | 149 | [
"Glass engineering and science",
"Materials science"
] |
58,018,766 | https://en.wikipedia.org/wiki/CERN%20ritual%20hoax | The CERN ritual hoax is a found footage video that depicts a faux occult ritual occurring in the grounds of CERN, the intergovernmental organization that operates the largest particle physics laboratory in the world. The video became popular in August 2016 and shows several people dressed in black cloaks surrounding a statue of the Hindu deity Shiva and apparently performing a human sacrifice, in apparent mockery of existing conspiracy theories which suggest that CERN aims to use the Large Hadron Collider to create a portal to hell, summon the antichrist, or destroy the universe. The video ended with the person filming crying out and running away.
Reactions
A CERN spokesperson stated that the video was a prank and that no one was actually harmed. CERN stated in its FAQ that the video was "fiction" and the actions were outside its professional guidelines and without any official permission. CERN stated that it "doesn't tolerate this kind of spoof" and that it can "give rise to misunderstandings about the scientific nature of our work".
References
CERN
Internet hoaxes
Satanic ritual abuse
2016 hoaxes
Religion and science
Religious hoaxes
Religious controversies in Switzerland
Science and technology-related conspiracy theories
Shiva | CERN ritual hoax | [
"Technology"
] | 241 | [
"Science and technology-related conspiracy theories"
] |
58,019,317 | https://en.wikipedia.org/wiki/List%20of%20locations%20and%20entities%20by%20greenhouse%20gas%20emissions | This article is a list of locations and entities by greenhouse gas emissions, i.e. the greenhouse gas emissions from companies, activities, and countries on Earth which cause climate change. The relevant greenhouse gases are mainly: carbon dioxide, methane, nitrous oxide and the fluorinated gases bromofluorocarbon, chlorofluorocarbon, hydrochlorofluorocarbon, hydrofluorocarbon, nitrogen trifluoride, perfluorocarbons and sulfur hexafluoride.
The extraction and subsequent use of fossil fuels coal, oil and natural gas, as a fuel source, is the largest contributor to global warming.
Carbon dioxide
Ranked 10 most countries
During June of 2023, with 12705 million tonnes CO2e produced, China is the largest emitter; United States is second with 6,001, India 3,394, EU (which is 27 countries) 3,383, Russia 2,476, Japan 1,166, Brazil 1,057, Indonesia 1,002, Iran 893, and Canada 736.
Scope 1+3 emissions, cumulative of the years 1988 - 2015, from oil and gas extraction
This section uses data from a climate accountability report of Heede of the Carbon Accountability Institute, and van Der Vlugt and Griffin of the Carbon Disclosure Project. While data of emissions "Direct operational" and indirectly caused from the companies surveyed were indicated by the CDP, requests for data which were ignored by companies and emissions resulting from the use of products originating with companies were included as estimates by the researchers. The data used by the CDP scientists is a composite of quantities of emissions as described via the GHG Protocol Corporate Standard (GHGPCS): Scope 1 and Scope 3 emissions (not including Scope 2) - these three being all the possible Scope-emission types. 1 is direct emissions sources from a companies owned or possessed resources, 3 is indirect sources subsequential from production activities; these are divided by GHGPCS into types: upstream and downstream, and 15 categories. Scope 3 emissions are thought to be approximately 90% of the total from any company and result from the combustion of coal, and, or, oil, and, or, gas during the conversion of these into energy i.e. as fuel; which is categorized as a downstream. The relevant tables below have a ranking of 20 industrial greenhouse gas emitters from 1988 to 2015 from the Carbon Majors Database (CDP) report, a 10 July 2017 dataset of GtCO2e.
The table below shows the total combined (cumulative) emissions as a percentage of all emissions. Oil and gas production data was obtained from annual reports from company websites and the SEC (2016). For some state owned enterprises, data was sourced from the ‘Oil & Gas Journal’ (1986-2016)
or is estimated from national statistics (EIA 2017, BP 2016, and OPEC 2016):
All cause 1+3 cumulative emissions
The Guardian newspaper (England, Britain) and Acciona (bracketed); both citing CDP:
Scope 3
Scope 3 emissions are thought to be approximately 90% of the total from any company (Scope 1) and result from fuel combustion.
Vehicle emissions
Pickup trucks were found to produce the most emissions in a group of vehicles including SUVs and cars, in a survey reported January 2022. Excluding pickup trucks, the most polluting car type surveyed 2017 is the 2011 - 2020 Jeep Grand Cherokee which creates 372 grams per kilometre from the exhaust pipe, the 2007 - 2014 Audi R8 creates 346, thirdly the Chevrolet Camaro 335, the tenth most polluting, the Porsche Macan creates 291.
Home: cooking fuels and technologies
The World Health Organization considers that during 2018 approximately 3 billion people, which was more than 40% of the 2018 estimated global population, used polluting fuel sources in their residences.
Largest sources carbon dioxide (Scope 1)
This part details most emissions for the year 2021 using Climate TRACE:
Largest point source (Scope 1)
This section details production sites at single locations where the most pollution exists or existed in the recent past.
During March 2020, Secunda CTL, owned by Sasol, a synthetic fuel and chemicals from coal plant in Secunda, South Africa, was the producer of the single most emissions, at 56.5 million tonnes of a year. The Department of Forestry, Fisheries, and the Environment (DFFE) of the Government of South Africa determined Sasol has until 1 April 2025 to comply with the legal limits for emissions, as described by the Air Quality Act 2004:Part 3; 12; Category 3. Sasol's pledge to reduce its emissions from the plant by 10% by 2030 was reported during November 2020, during 2023 it was reported that this was amended to 30%.
the gas-fired power plant which emits the most was the Taichung Power Station in Taiwan, at 34.19 million tonnes .
Methane
Sources of anthropogenic production are in the majority:
natural gas, petroleum, and coal mining: the United States produced the most recent emissions from oil and gas sources at least prior to April 2023.
livestock production systems; manure and enteric fermentation,
waste deposit sites: landfills waste water
Carbon bomb projects (new extractions)
A carbon bomb, or climate bomb, is any new extraction of hydrocarbons from underground whose potential greenhouse gas emissions exceed 1 billion tonnes of worldwide. In 2022, a study showed that there are 425 fossil fuel extraction projects (coal, oil and gas) with potential CO2 emissions of more than 1 billion tonnes worldwide. The potential emissions from these projects are twice the 1.5°C carbon budget of the Paris Agreement. According to these researchers, defusing carbon bombs should be a priority for climate change mitigation policy.
According to the same study, the Global Energy Monitor and "Banking on Climate Chaos" associations, between 2016 and 2022, the main backers of these climate bombs are the American banks JPMorgan Chase, Citibank and Bank of America.
Between 2020 and 2022, at least twenty new "climate bombs" went into operation, reveals an international journalistic investigation. In this survey, France's TotalEnergies is cited as the second most responsible group for fossil mega-fields, with a presence at 23 major hydrocarbon extraction sites. In November 2023, China's China Energy will lead the ranking and Saudi Aramco of Saudi Arabia will be third.
Examples
Exploitation of new coal mines in Australia.
Exploiting Canada's oil sands.
Shale gas extraction, for instance in Permian basin in Texas
See also
Afşin-Elbistan C power station
Non-linear effects
Non-methane volatile organic compound
References
External links
Stephen Conmy 4 April 2023 News Analysis The 20 most polluting companies in the world https://www.thecorporategovernanceinstitute.com/
For "carbon bomb" projects:
carbonbombs.org
leave-it-in-the-ground.org
permianclimatebomb.org
Carbon Bomb Map
Climate change
History of climate variability and change
Greenhouse gas
Environmental disasters
Greenhouse gas emissions | List of locations and entities by greenhouse gas emissions | [
"Chemistry"
] | 1,458 | [
"Greenhouse gases",
"Greenhouse gas emissions"
] |
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