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71,216,636 | https://en.wikipedia.org/wiki/2%2C4%2C6-Heptanetrione | 2,4,6-Heptanetrione is the organic compound with the formula . It is a white or colorless solid. The molecule, which exists mainly in the enol form, undergoes condensation with 1,2-diketones. The compound contributes to the flavor of strawberries. It forms a variety of metal complexes.
See also
Triacetylmethane, an isomer
Refercences
Triketones
Chelating agents
Ligands
3-Hydroxypropenals
Enols
Tridentate ligands | 2,4,6-Heptanetrione | [
"Chemistry"
] | 109 | [
"Enols",
"Ligands",
"Coordination chemistry",
"Functional groups",
"Chelating agents",
"Process chemicals"
] |
71,216,996 | https://en.wikipedia.org/wiki/Shikargah | Shikargah ( śikārgāh), from Persian shikārgāh meaning shikār hunting + gāh ground, is often described as a hunting ground where 'qamargah' or encircling of game occurs, an overtone of war exercise performed within a controlled arena of flora and fauna to create easier shooting and camping for hunting party.
The Mughals, who already had a hunting tradition in Central Asia, brought the practice to India upon their conquest of the subcontinent. On such occasions unresolved matters of courts were settled which included conspiration and preparation for mutinying, raising of invasion forces.
The British continued to entertain their dignitaries with elaborate tiger hunts famously known as "hunting party" at these Shikargah.
Jim Corbett National Park established in 1932 was first Shikargah turned into a national park during British India, only 40,000 tigers were left during India's independence in 1947, the first-ever all-India tiger census conducted in 1972 revealed the existence of only 1,827 tigers. Realizing the gravity of dwindling number of seven major big cats of the world — tigers, lions, leopards, snow leopards, pumas, jaguars and cheetahs, Indian Govt enacted Wild Life (Protection) Act, 1972. As of December 2024, there are 57 protected areas that have been designated as tiger reserves. , among which important tiger reserves where the numbers are more than 100 in each respectively are Corbett, Rajaji, Pilibhit, Dudhwa, Bandhavgarh, Nagarhole, Mudumalai, Kaziranga, Sunderbans and Bandipur.
Today India boasts 104 national parks, 551 Wildlife Sanctuaries, 131 Marine Protected Areas, 18 Biosphere Reserves, 88 Conservation Reserves (57 Tiger Reserves) and 127 Community Reserves, covering a total of 1,65,088.57 sq km. In total, there are 870 Protected Areas which make 5.06% of the geographical area of the country where 3,682 big cats are estimated ranking India with topmost share of 75% worldwide in 2022.
Chronicled Shikargah
Terrorizing wild beasts were often tamed by Mughals who considered themselves as protectors of people, sources record over seventy shikargahs situated in mountainous forests, deserts, Indo-Gangetic floodplains, rocky outcrops, and coastlands.
Agra Shikargah, Uttar Pradesh
Ajmer Ana Sagar Lake, Nur Chashma Shikargah, Rajasthan
Burhanpur Bagh-i Zaynabad Shikargah, Madhya Pradesh
Hissar-i-Firuza Shikargah, Haryana
Narwar Shikargah
Pakpattan Shikargah Pakistan
Mahemdavad Shikargah Ahmedabad, Gujrat
Palam, Delhi Shikargah, New Delhi
Sheikhupura (Jahangirpur/Jahangirabad) Shikargah, Lahore, Pakistan
Earliest attempt of conservation of Shikargah
Shikargah Weave
In Popular Culture
In movie The Deceivers (film) (1988), the hunting party scene includes the phrase: "There is no greater pleasure than the hunt, for it reveals the essence of life and death." This line reflects the cultural and philosophical undertones of the film, which explores themes of deception, power, and morality in colonial India.
Gallery
Notes
References
Wildlife conservation
Shikargah
Wildlife conservation in India
Conservation-reliant species | Shikargah | [
"Biology"
] | 717 | [
"Wildlife conservation",
"Biodiversity"
] |
71,217,186 | https://en.wikipedia.org/wiki/Neodymium%20bismuthide | Neodymium bismuthide or Bismuth-Neodymium is a binary inorganic compound of neodymium and bismuth with the formula NdBi. It forms crystals.
Preparation
Neodymium bismuthide can be prepared by reacting a stoichiometric amount of neodymium and bismuth at 1900°C:
Nd + Bi → NdBi
Physical properties
Neodymium bismuthide forms cubic crystals of the space group Fm3m, with cell parameters a = 0.64222 nm, Z = 4 with a structure like sodium chloride. The compound melts at 1900°C. At a temperature of 24 K, an antiferromagnetic transition occurs in the compound.
References
Neodymium(III) compounds
Bismuth compounds
Bismuthides
Rock salt crystal structure | Neodymium bismuthide | [
"Chemistry"
] | 168 | [
"Inorganic compounds",
"Inorganic compound stubs"
] |
75,514,044 | https://en.wikipedia.org/wiki/Radio%20Spectrum%20Management | The Radio Spectrum Management (RSM) is a New Zealand public service business unit within the Ministry of Business, Innovation and Employment (MBIE) that is in charge of the radio spectrum and radio-related regulations in New Zealand.
Radio Spectrum Management is charged with regulating New Zealand's radio spectrum activities such as planning, allocations, and licensing.
References
Government agencies of New Zealand
Ministry of Business, Innovation and Employment
Radio in New Zealand
Radio spectrum | Radio Spectrum Management | [
"Physics"
] | 91 | [
"Radio spectrum",
"Spectrum (physical sciences)",
"Electromagnetic spectrum"
] |
75,514,302 | https://en.wikipedia.org/wiki/Buxtehudeidae | Buxtehudeidae is a family of microsporidian fungi. It contains two species in two genera, Buxtehudea scaniae and Jiroveciana limnodrili. Both genera are parasitic: Buxtehudea infects archaeognath bristletails, while Jiroveciana infects tubifex worms.
References
Microsporidia
Fungus families | Buxtehudeidae | [
"Biology"
] | 83 | [
"Fungus stubs",
"Fungi"
] |
75,514,824 | https://en.wikipedia.org/wiki/Fidanacogene%20elaparvovec | Fidanacogene elaparvovec, sold under the brand name Beqvez among others, is a gene therapy delivered via adeno-associated virus used for the treatment of hemophilia B (congenital Factor IX deficiency).
Fidanacogene elaparvovec was approved for medical use in Canada in December 2023, in the United States in April 2024, and in the European Union in July 2024.
Medical uses
In the US, fidanacogene elaparvovec is indicated for the treatment of adults with moderate to severe hemophilia B (congenital factor IX deficiency) who currently use factor IX prophylaxis therapy; or have current or historical life-threatening hemorrhage; or have repeated, serious spontaneous bleeding episodes; and do not have neutralizing antibodies to adeno-associated virus serotype Rh74var (AAVRh74var) capsid as detected by an FDA-approved test. It is given as a one-time infusion.
Society and culture
Legal status
Fidanacogene elaparvovec was approved for medical use in Canada in December 2023, in the United States in April 2024, and in the European Union in July 2024. The FDA granted the application breakthrough therapy designation.
In May 2024, the Committee for Medicinal Products for Human Use of the European Medicines Agency adopted a positive opinion, recommending the granting of a conditional marketing authorization for the medicinal product Durveqtix, intended for the treatment of severe and moderately severe hemophilia B. The applicant for this medicinal product is Pfizer Europe MA EEIG. The conditional marketing authorization was granted in July 2024.
Economics
Pfizer announced a cost of 3.5 million per treatment, the same cost as the CSL Behring's competing hemophilia gene therapy etranacogene dezaparvovec.
Research
Fidanacogene elaparvovec partially restored factor IX production in preliminary studies. The results of a phase 3 trial were published in September 2024. It showed that even 15 months after treatment factor IX was still being expressed and the number of bleedings had decreased significantly compared to the time before the treatment, when study participants had been given prophylactic infusions of factor IX.
References
External links
Antihemorrhagics
Gene therapy
Haemophilia drugs | Fidanacogene elaparvovec | [
"Engineering",
"Biology"
] | 502 | [
"Gene therapy",
"Genetic engineering"
] |
75,516,328 | https://en.wikipedia.org/wiki/Resisting%20AI | Resisting AI: An Anti-fascist Approach to Artificial Intelligence is a book on artificial intelligence (AI) by Dan McQuillan, published in 2022 by Bristol University Press.
Content
Resisting AI takes the form of an extended essay, which contrasts optimistic visions about AI's potential by arguing that AI may best be seen as a continuation and reinforcement of bureaucratic forms of discrimination and violence, ultimately fostering authoritarian outcomes. For McQuillan, AI's promise of objective calculability is antithetical to an egalitarian and just society. McQuillan uses the expression "AI violence" to describe how – based on opaque algorithms – various actors can discriminate against categories of people in accessing jobs, loans, medical care, and other benefits.
The book suggests that AI has a political resonance with soft eugenic approaches to the valuation of life by modern welfare states, and that AI exhibits eugenic features in its underlying logic, as well as in its technical operations. The parallel is with historical eugenicists achieving saving to the state by sterilizing defectives so the state would not have to care for their offspring.
The analysis of McQuillan goes beyond the known critique of AI systems fostering precarious labour markets, addressing "necropolitics", the politics of who is entitled to live, and who to die. Although McQuillan offers a brief history of machine learning at the beginning of the book – with its need for "hidden and undercompensated labour", he is concerned more with the social impacts of AI rather than with its technical aspects. McQuillan sees AI as the continuation of existing bureaucratic systems that already marginalize vulnerable groups – aggravated by the fact that AI systems trained on existing data are likely to reinforce existing discriminations, e.g. in attempting to optimize welfare distribution based on existing data patterns, ultimately creating a system of "self-reinforcing social profiling".
In elaborating on the continuation between existing bureaucratic violence and AI, McQuillan connects to Hannah Arendt's concept of the thoughtless bureaucrat in Eichmann in Jerusalem: A Report on the Banality of Evil, which now becomes the algorithm that, lacking intent, cannot be accountable, and is thus endowed with an "algorithmic thoughtlessness".
McQuillan defends the "fascist" in the title of the work by arguing that while not all AI is fascist, this emerging technology of control may end up being deployed by fascist or authoritarian regimes. For McQuillan, AI can support the diffusion of states of exception, as a technology impossible to properly regulate and a mechanism for multiplying exceptions more widely. An example of a scenario where AI systems of surveillance could bring discrimination to a new high is the initiative to create LGBT-free zones in Poland.
Skeptical of ethical regulations to control the technology, McQuillan suggests people's councils and workers' councils, and other forms of citizens' agency to resist AI. A chapter titled "Post-Machine Learning" makes an appeal for resistance via currents of thought from feminist science (standpoint theory), post-normal science (extended peer communities), and new materialism; McQuillan encourages the reader to question the meaning of "objectivity" and calls for the necessity of alternative ways of knowing. Among the virtuous examples of resistance – possibly to be adopted by the AI workers themselves – McQuillan notes the Lucas Plan of the workers of Lucas Aerospace Corporation, in which a workforce declared redundant took control, reorienting the enterprise toward useful products.
The work of McQuillan
In an interview about the book, McQuillan defines himself as an "AI abolitionist".
Reception
The book is praised for "masterfully
disassembles AI as an epistemological, social, and political paradigm, and for his examination of how most of the data that is fed into "privatized AI infrastructure is “amputated” from context or embodied experience and ultimately processed through crowdsourcing."
On the critical side, a review in the academic journal Justice, Power and Resistance took exception to the "nightmarish visions of Big Brother" offered by McQuillan, and argued that while many elements of AI may pose concern, a critique should not be based on a caricature of what AI is, concluding that McQuillan's work is "less of a theory and more of a Manifesto". Another review notes "a disconnect between the technical aspects of AI and the socio-political analysis McQuillan provides."
Although the book was published before the ChatGPT and large language model debate heated up, the book has not lost relevance to the AI discussion. It is noted for suggesting a link between beliefs in artificial intelligence and beliefs in a racialised and gendered visions of intelligence overall, whereby a certain type of rational, measurable intelligence is privileged, leading to "historical notions of hierarchies of being".
The blog Reboot praised McQuillan for offering a theory of harm of AI (why AI could end up hurting people and society) that does not just encourage tackling in isolation specific predicted problems with AI-centric systems: bias, non-inclusiveness, exploitativeness, environmental destructiveness, opacity, and non-contestability.
For educational policies could also look at AI following the reading of McQuillan:
Videos and podcasts with an interest in AI and emerging technology have discussed the book.
See also
Shoshana Zuboff
Surveillance capitalism
Weapons of Math Destruction
Alain Supiot
References
External links
Algorithmic Justice League
Cardiff University: Data Justice Lab, School of Journalism, Media and Culture.
Artificial intelligence
Quantification (science)
Science and technology studies
2022 non-fiction books
Non-fiction books about Artificial intelligence | Resisting AI | [
"Mathematics",
"Technology"
] | 1,183 | [
"Quantity",
"Science and technology studies",
"Quantification (science)"
] |
75,517,853 | https://en.wikipedia.org/wiki/HD%20194783 | HD 194783 (HR 7817; 2 G. Microscopii) is a solitary star located in the southern constellation Microscopium near the border with Sagittarius. It is barely visible to the naked eye as a bluish-white-hued point of light with an apparent magnitude of 6.08. The object is located relatively far at a distance of 740 light-years based on Gaia DR3 parallax measurements, but it is drifting closer with a heliocentric radial velocity of . At its current distance, HD 194783's brightness is diminished by an interstellar extinction of 0.31 magnitudes and it has an absolute magnitude of either −0.59 or −1.10, depending on the source.
HD 194783 has a stellar classification of B8 II/III, indicating that it is an evolved B-type star with the blended luminosity class of a bright giant and a lower luminosity giant star. It has also been given a class of B9pHgMn, indicating that it is a chemically peculiar mercury-manganese star. It has 4.03 times the mass of the Sun and a slightly enlarged radius 4.19 times that of the Sun's. It radiates 390 times the luminosity of the Sun from its photosphere at an effective temperature of . The heavy metal (iron) to hydrogen ratio–what astronomers dub as the star's metallicity–is 63% that of the Sun's. HD 194783 is estimated to be approximately 70 million years old.
In 1989, HD 194783 was reported to be a spectrum variable with a period of 6 days. The projected rotational velocity of the star is not known, but it is said to be no higher than . HD 194783 was also observed to have a relatively weak magnetic field of about −43 gauss.
References
Mercury-manganese stars
B-type giants
B-type bright giants
Microscopium
Microscopii, 2
CD-36 14166
194783
101017
7817
00034864575 | HD 194783 | [
"Astronomy"
] | 432 | [
"Microscopium",
"Constellations"
] |
75,517,927 | https://en.wikipedia.org/wiki/IEEE%20Transactions%20on%20Dielectrics%20and%20Electrical%20Insulation | IEEE Transactions on Dielectrics and Electrical Insulation is a peer-reviewed scientific journal published bimonthly by the Institute of Electrical and Electronics Engineers. It was co-founded in 1965 by the IEEE Dielectrics and Electrical Insulation Society under the name IEEE Transactions on Electrical Insulation. The journal covers the advances in dielectric phenomena and measurements, and electrical insulation. Its editor-in-chief is Michael Wübbenhorst (KU Leuven).
According to the Journal Citation Reports, the journal has a 2022 impact factor of 3.1.
References
External links
Dielectrics and Electrical Insulation, IEEE Transactions on
English-language journals
Academic journals established in 2016
Bimonthly journals
Electronics journals
Materials science journals | IEEE Transactions on Dielectrics and Electrical Insulation | [
"Materials_science",
"Engineering"
] | 147 | [
"Materials science journals",
"Materials science"
] |
75,518,593 | https://en.wikipedia.org/wiki/Compass%20Datacenters | Compass Datacenters LLC Is an American multinational data center company. It is a significant player in the hyperscale computing space, with approximately 17 active datacenter campuses in the US, and internationally in Canada and Israel.
Since 2023, the company has been controlled by the private equity arms of Ontario Teachers' Pension Plan and Brookfield Infrastructure Partners.
Compass' partners include Schneider Electric, Cummins, Foster Fuels, Vertiv and Salute.
History
Compass Datacenters was founded in 2011 by Chris Crosby, who previously was a senior vice president of Digital Realty with a focus on modular datacenters. In 2014, the company received a patent noting that they had created a truly modular datacenter.
Compass wholly owns a software as a service company known as Radix IoT that specializes in datacenter management software.
Compass initially started with a focus on US operations however eventually expanded abroad. Specifically to Canada through the acquisition of ROOT datacenters in 2019 and expansion to Israel directly through a partnership with Amazon Web Services. In the same time period Azrieli Group acquired a 20% stake in the organization. In 2023 the company acquired the former Sears HQ in Illinois to create a datacenter mega campus. On December 13, 2023, it was confirmed the Compass Datacenters Prince William County project, one of the largest in the world, was set to go through after a 4–3 vote in favor of development.
On June 26, 2023, it was announced that Brookfield Infrastructure Partners and Ontario Teachers' Pension Plan had purchased the company.
References
External links
Official website
American companies established in 2011
Companies based in Dallas
Data centers
2011 establishments in Texas
2023 mergers and acquisitions | Compass Datacenters | [
"Technology"
] | 344 | [
"Data centers",
"Computers"
] |
75,519,801 | https://en.wikipedia.org/wiki/One%20Water%20%28water%20management%29 | One Water is a term encompassing the management of all water sources in an integrated and sustainable way considering all water sources and uses. This idea stems from core principles of providing affordable water access for everyone.
Origins and influences
The term “One Water” refers to integrated and effective water management practices that are “older than Texas.” Holistic, system-wide, interconnected approaches to water have been used before.
Holistic water planning by municipalities has become an international trend. The international water community developed Integrated Water Resources Management (IWRM) in the early 2000s to protect water resources and promote sustainability. The Global Water Partnership has an IWRM Action hub to share information and insights into implementing an integrated water program.
Definition and core principles
The Water Research Foundation (WRF) defines One Water as an integrated planning and implementation approach to managing finite water resources for long-term resilience and reliability, meeting both community and ecosystem needs. While many cities manage various water sources and disposal systems separately, One Water emphasizes integrating water and land resources for a holistic planning approach to water management. The importance of all water sources is stressed. One Water principles involve taking an interconnected approach to complex issues such as water infrastructure crises, environmental and public health crises, droughts, and climate change at a all scales: individual and building, local, regional, state, country, and international.
Related scholarly research
Jiang et al. 2021 developed a model using One Water concepts to show how thinking about interconnections can improve modeling and assessing the hydrologic cycle.
Initiatives and organizations
The United Nations and World Health Organization host the WHO/UNICEF Joint Monitoring Programme (JMP) for Water Supply, Sanitation and Hygiene Program that uses One Water principles to monitor progress on local to global scales for attaining Sustainable Development Goal targets for “universal and equitable access to safe drinking water, sanitation, and hygiene.”
The Environmental Protection Agency noted that meeting the Clean Water Act (1972 requirements for managing and accessing water would be more efficient using an overall approach to water management. The agency, along with the National Oceanic and Atmospheric Administration (NOAA) and the U.S. Water Alliance have provided webinars and other guidance for using a One Water approach for water management. The U.S. Water Alliance also has more initiatives to support One Water, including the One Water Council to bring organizations together, and Value of Water Campaign to educate about the importance of all water sources.
One Water Panel helps develop strategies for integrating water source development and management to more effectively meet present and future water needs and address climate change impacts.
The National Association of Clean Water Agencies (NACWA) and Association of Metropolitan Water Agencies (AMWA) have developed a campaign for Affordable Water, Resilient Communities to increase political awareness around water issues.
Examples of One Water strategies and implementation
Water management education
American Rivers uses a holistic approach to water management and hosted a 2-day conference to collect ideas for helping cities adapt an integrated water management approach in 2016.
The Southeast Michigan Council of Governments (SEMCOG) has a One Water Program to educate about water use and systems and their interrelationships and as a water stewardship approach. They hosted events at the 2023 Great Lakes and Fresh Water Week, posted videos to showcase benefits of a one-water approach, and have a series of articles.
The University of Illinois Urbana-Champaign includes One Water among five curricula toward a Bachelor of Science degree in Environmental engineering. Their One Water program emphasizes application of physical, chemical, and biological principles to design innovative water quality control processes for safe and reliable community or household drinking water, sanitation, stormwater management, and resource (water, nutrient, energy) recovery systems.
Infrastructure and sustainability
One Water concepts are also used in building planning and sustainable development. Blue Hole Primary School, Texas used One Water concepts as it built the school.
Cities
Cities have developed a variety of One Water Strategies, and there is guidance and studies for helping more cities develop their plans. The Water Research Foundation and Colorado State University are developing guidance for One Water Cities (2020–2023). International Water Association developed a Cities of the Future integrated water management program.
United States
The City of Los Angeles launched the One Water LA 2040 Plan, an integrated and unified approach to sustainably manage all water resources—surface water, groundwater, potable water, wastewater, recycled water, and stormwater.
Palo Alto is developing a One Water Plan as part of their climate Action-Protection and Adaptation planning priority.
San Francisco, California, has a broad OneWater SF Vision with many resources into their water planning, including “water, energy, financial, human, community partnerships and natural resources”
Denver, Colorado, adopted a One Water Plan in September 2021.
Wake County, North Carolina started a One Water Plan for its municipalities with a public visioning survey in May 2023.
Milwaukee, Wisconsin, has a One Water approach with information tailored to different audiences at #onewaterourwater
Worldwide
Vancouver, British Columbia, uses a One Water Approach to address changes in its watershed.
Awards
One Water Panel Honolulu received the US Water Prize for the Outstanding Public Sector Category, US Water Alliance in 2022
One Water conferences
One Water Summits were held in 2015, 2017 (New Orleans, Louisiana), and 2018 (Twin Cities, Minnesota)
A City Summit for cities to adapt One Water plans was held in Charlotte, North Carolina November 15–18, 2017.
One Water Summit 2024: Kazakhstan-France Climate Initiative (bnn.network). The planned One Water Summit is a crucial part of a series of combined actions by Kazakhstan and France to address climate issues on a global scale.
See also
Reclaimed water
Water conservation
References
Water treatment
Water management | One Water (water management) | [
"Chemistry",
"Engineering",
"Environmental_science"
] | 1,153 | [
"Water treatment",
"Water pollution",
"Water technology",
"Environmental engineering"
] |
75,520,167 | https://en.wikipedia.org/wiki/Leriglitazone | Leriglitazone is a PPAR-gamma agonist and metabolite of the glitazone pioglitazone. It is developed for adrenomyeloneuropathy, and other neurodegenerative diseases.
Society and culture
Legal status
In January 2024, the European Medicines Agency (EMA) recommended the refusal of the marketing authorization for leriglitazone (Nezglyal) requested by Minoryx Therapeutics S.L. In May 2024, the EMA confirmed its recommendation to refuse marketing authorization for leriglitazone. Leriglitazone was intended for the treatment of cerebral adrenoleukodystrophy.
References
Thiazolidinediones
Experimental drugs | Leriglitazone | [
"Chemistry"
] | 150 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
75,520,290 | https://en.wikipedia.org/wiki/Ministry%20of%20Minerals%20and%20Energy%20%28Botswana%29 | The Ministry of Minerals and Energy is a ministry within the Cabinet of Botswana. The current minister is Bogolo Kenewendo.
Departments
Department of Corporate Services
Department of Mines
Department of Energy
Mineral Affairs Division
Diamond Hub
Projects & Energy Development Unit
Ministers
Lefoko Maxwell Moagi (6 November 2019-)
References
Energy ministries
Mining ministries
Government ministries of Botswana | Ministry of Minerals and Energy (Botswana) | [
"Engineering"
] | 71 | [
"Energy organizations",
"Energy ministries"
] |
75,520,475 | https://en.wikipedia.org/wiki/Diethofencarb | Diethofencarb is a carbamate fungicide which is used to control Botrytis infections on a variety of fruit and vegetable crops.
References
Fungicides
Ethoxy compounds
Isopropyl esters
Carbamates
Anilines | Diethofencarb | [
"Chemistry",
"Biology"
] | 52 | [
"Fungicides",
"Biocides"
] |
75,521,522 | https://en.wikipedia.org/wiki/Cosmic%20coincidence | In cosmology, the cosmic coincidence is the observation that at the present epoch of the universe's evolution, the energy densities associated with dark matter and dark energy are of the same order of magnitude, leading to their comparable effects on the dynamics of the cosmos. This coincidence is puzzling because these energies have vastly different effects on the universe's expansion—dark matter tends to slow down expansion through gravitational attraction, while dark energy seems to accelerate it. The observed similarity in the magnitudes of these two components' energy densities at this particular epoch in the universe's history raises questions about whether there might be some underlying physical connection or shared origin between dark matter and dark energy. Indeed, some theories attempt to explain this coincidence by proposing that they are different manifestations of the same fundamental force or field.
References
See also
Fine-tuned universe
Physical cosmology
Unsolved problems in physics | Cosmic coincidence | [
"Physics",
"Astronomy"
] | 182 | [
"Theoretical physics",
"Unsolved problems in physics",
"Astrophysics",
"Physical cosmology",
"Astronomical sub-disciplines"
] |
75,522,250 | https://en.wikipedia.org/wiki/LooCafe | LooCafe is an Indian public toilet model, built out of shipping containers with a point of sale attached with additional features. The company, legally incorporated as Ixora Corporate Services, works in the WASH industry.
LooCafe is designed to end open defecation and public urination onto buildings, sidewalks, or streets, and create access to public toilets under the Swachh Bharat Mission.
History
Founded in 2018 by Abhishek Nath, LooCafe started from Hyderabad and now are currently operational in multiple Indian states and districts, including Jammu and Kashmir, Tamil Nadu and Telangana.
Model
Most public toilets in India fail because of maintenance issues and a variety of government challenges.
LooCafes are designed to be sustainable models because of their business model. Revenue from the café or point of sale helps them sustain the public toilets that are built towards the back out of the shipping container. The usage of IoT devices and facility management technology have also helped them expand their footprint to 350 units across India. In 2019, they won Confederation of Indian Industry awards.
Institutions
LooCafes have worked with the British Council, Hyderabad Design Week, and the Greater Hyderabad Municipal Corporation (GHMC).
For their social work a book was also launched titled Toilet Tales.
The toilets have operated during the COVID-19 pandemic in India with respect to disinfection work for public facilities.
LooCafe models
References
Toilets
Water supply and sanitation in India
2018 establishments in India | LooCafe | [
"Biology"
] | 300 | [
"Excretion",
"Toilets"
] |
75,522,951 | https://en.wikipedia.org/wiki/Mathikilhi%20Eco%20Garden | Mathikilhi Eco Garden (; is a wetland or a grassland in Meedhoo, Addu City, Maldives.There many water lakes in the Eco garden. The biggest water lake 'Fenfila koaru' is in the center of the wetland. Mathikilhi Eco garden is the first Wetland Garden in the Maldives. The wetland's some of the water lakes were dug by people themselves. The beauty of Eco Garden is shown by the water lakes and the grasses.
The eco-garden was built by a group of people from Meedhoo The eco-garden began operations in 2016. The Eco garden is under the protection of the Ministry of Climate Change, Environment and Energy, and Addu City council. The ponds in the Eco garden are known to have a few freshwater fish species including, Greenstripe barb (Puntius vittatus) and a species of Swamp eel. Mathikilhi eco garden is around 50 hectors big.
See also
Hulhumeedhoo
Addu City
Addu Atoll
Maldives
References
Hulhumeedhoo
Islands of the Maldives
Addu Atoll
Grasslands | Mathikilhi Eco Garden | [
"Biology"
] | 229 | [
"Grasslands",
"Ecosystems"
] |
75,523,249 | https://en.wikipedia.org/wiki/Wildlife%20of%20Brunei | The wildlife of Brunei is one of its primary attractions. Tropical evergreen rainforest makes up the majority of the country's natural vegetation. 81% of the land is covered by forests, with 59% being primary forests and 22% being secondary forests and plantations. With an estimated 2,000 species of trees, Brunei is home to an estimated 15,000 species of vascular plants. Brunei's mammal and bird populations are comparable to those of Sumatra, the Malaysian Peninsula, and Borneo as a whole.
As far as Asian countries go, Brunei was the first to ban shark finning. Dog beating and wildlife trafficking are Brunei's two most urgent animal law concerns. Like many other Asian nations, the nation has some animal-related legislation, but enforcement is lax.
Terrestrial fauna
A wide variety of wildlife can be found in Brunei's forests, including 500 species of marine fish and invertebrates, 622 species of birds, 121 species of mammals, 182 species of amphibians and reptiles, and some native species like the Nycticebus borneanus, Bronchocela cristatella, Bornean sun bear, and Pelobatrachus nasutus. Proboscis monkeys and ground squirrels are endemic to Brunei. The nation is home to two species of crocodiles: the false gharial and the estuary crocodile. The varied range of freshwater crocodiles are found in Brunei's small torrential streams, estuaries with highly acidic environments, and alkaline waters.
Mammals
In Brunei, several mammal species, including the Asian elephant, banteng, long-footed treeshrew, orangutan, and otter civet, are classified as critically endangered or endangered, while the bay cat, clouded leopard, dugong, flat-headed cat, smooth-coated otter, marbled cat, pig-tailed macaque, and proboscis monkey are listed as vulnerable, according to the 2004 IUCN Red List of Threatened Species.
Birds
The rainforest of Brunei is a habitat to numerous hornbills, barbets, sunbirds, spiderhunters, leafbirds, trogons, and floor-dwelling species including pheasants, pittas, and wren-babblers. The riverine and coastal habitats, which comprise freshwater marshes and mangroves are significant locations. Birds are numerous on the hillsides of Brunei, which border the Malaysian state of Sarawak. But accessing some of these regions can be difficult, particularly during the monsoon season.
Terrestrial flora
One of the oldest rainforests in the world, Temburong is home to rainforests that date back more than 150 million years. Many plant and animal species, some of which are unique to Brunei and Borneo, can be found in abundance in the woodlands. Of the country's total land area, 72% is covered by forest, and 41% is legally protected. Over 70% of Brunei is made up of lush, verdant jungles that have been kept out of human grasp.
The greatest remaining intact mangroves in northern Borneo are found in the coastal mangroves. In Brunei Bay, they make up one of the biggest areas of comparatively untouched mangroves in eastern Asia, along with those in nearby nations. Although less so than in other nations in the region, mangroves are used for a variety of purposes. With more than 50% live coral cover, the coral reef along the coast is most famous for the rare co-occurrence of a very distinctive suite of hard and soft corals and gorgonian sea fans.
Brunei boasts 400 species of reef-building coral, with the majority of its peat swamp forests situated along the Belait River basin in the west and seasonally flooded areas in the middle reaches of the Tutong River, all maintaining nearly perfect conditions. The limited exploitation of these forests is attributed to the population residing along the shore and the predominant role of hydrocarbon fossil fuels in the nation's development and economy; clear-cutting is prohibited, and timber exportation is not allowed, while the Forestry Department strictly regulates wood harvest for domestic use.
Conservation
Environmental issues
Ecosystem threats in the country includes land development, pollution, encroachment, climate change and invasive species. Meanwhile threats to the species includes poaching, collection and invasive alien species. These risks are fuelled by a number of factors, including economic expansion, the desire for products and services, the demand for exotic meat, traditional and herbal medicines, wild ornamental plants, and tourism in pristine places. These have resulted in the loss of species, habitat, ecosystem fragmentation, inland water pollution, and ecological benefits. There are also new dangers to biodiversity, such climate change. Numerous species are obtained to provide the global demand for meat, pets, luxury goods, medicines, and zoos.
Countermeasures
Forest reserves comprise all designated protected areas. The principal habitat categories are generally well-represented within the protected areas system, with the exception of swamp forest habitats. As of right now, Brunei's forest reserves are managed using sustainable management techniques in accordance with the ideas for forest development and conservation presented in the Strategic Plan for Forestry. Organisations (such as government ministries, NGOs, and higher education institutions) have undertaken initiatives to advance collaboration and exchange programs for biodiversity education and awareness raising. These initiatives include the organisation of seminars and conferences aimed at exchanging knowledge and expertise on biodiversity research and management, among other topics.
Field gene banks and arboretums are repositories of agricultural biodiversity and rice varieties. As part of the gene banks' efforts, the community was also given free seedlings of native fruit species. The Brunei National Herbarium has the only specimens of the country's flora. As part of its yearly conservation program, the Forestry Department of the government of Brunei plants trees. In only one year, the government pledged to plant 60,000 trees around the nation. Projects like this one that restore biodiversity are allotted land, and as part of the project, free seedlings were distributed to the local population.
BruWILD
An NGO called Brunei Biodiversity & Natural History Society (BruWILD) is dedicated to preserving biodiversity by action and education. Through its rescue operations and educational initiatives, BruWILD significantly contributed to the preservation of Brunei's wildlife and increased public understanding of the value of environmental sustainability. To commemorate World Environment Day in June 2017, the High Commission for Canada collaborated with BruWILD and the Collective.
To provide training for wildlife rescue and rehabilitation in Brunei, the International Wildlife Rehabilitation Council (IWRC) and BruWILD have partnered. 30 participants, including members of BruWILD, the Wildlife Division (Ministry of Primary Resources and Tourism), Universiti Brunei Darussalam (UBD), and International School Brunei (ISB), will be taught courses by IWRC instructors during their 25–30 July 2016 trip to Brunei. The courses would be held in the Faculty of Science laboratories at UBD.
Temburong
Temburong is renowned for its varied animals, waterfalls, and primary forests. One of Southeast Asia's best-preserved rainforests, Ulu Temburong National Park, is located in this area, alongside a cavern network in the Batu Apoi Forest Reserve.
The China State Construction Engineering Corporation (CSCEC) completed the Sultan Haji Omar Ali Saifuddien Bridge (Temburong Bridge) project inside the rural Temburong District that is primarily unoccupied and covered in virgin forest. Situated in the centre of the district, the easternmost region of Brunei, which is home to endemic fauna and indigenous vegetation, the company had to move forward with the megaproject while taking care to ensure that the natural landscape was damaged as little as possible. Additionally, workers have been told to record any wildlife encounters they may come across. Furthermore, eco-friendly practices are promoted, and trainings and inspections were carried out to guarantee that the flora and fauna are not affected.
Policies
The Wild Fauna and Flora Order 2007 provides for the implementation of the International Trade in Endangered Species of Wild Fauna and Flora Convention in Brunei, as well as procedures and requirements for obtaining permits and certificates to trade in, export, or import any species listed in the convention's appendices. Wild Life Protection 1984 provides for the protection of wildlife by limiting hunting seasons, animal age ranges, and hunting tactics, as well as establishing wildlife sanctuaries even within protected or reserved forests. The game officer shall have responsibility over and supervise compliance with the current act.
See also
List of parks in Brunei Darussalam
Tourism in Brunei
References
Biota of Brunei
Brunei | Wildlife of Brunei | [
"Biology"
] | 1,744 | [
"Biota by country",
"Biota of Brunei",
"Wildlife by country"
] |
75,523,943 | https://en.wikipedia.org/wiki/Vening%20Meinesz%20Medal | The Vening Meinesz Medal is an annual award for outstanding research in geodesy.
Background
The medal, inaugurated in 1994, has been awarded by the European Geosciences Union (EGU) since 2004, and before that by the European Geophysical Society (EGS). The medal is named in honor of Felix Andries Vening Meinesz, a Dutch geophysicists and geodesist, famous for his invention enabling precise measurements of gravity at sea. The portrait medal was designed by the Hungarian artist , renowned for his work as a medalist, goldsmith, and silversmith.
The medal should not be confused with the NWO Vening Meinesz Prijs, a prize given, every two years, to outstanding young scientists who work in the geosciences and are employed in the Netherlands.
Recipients
1998
1999 Anny Cazenave
2000 Ivan I. Mueller
2002 Georges Balmino
2002
2003 Véronique Dehant
2004 John M. Wahr
2005 Martine Feissel-Vernier
2006
2007 Thomas A. Herring
2008
2009 Susanna Zerbini
2010 Philip L. Woodworth
2011
2012 Che-Kwan Shum
2013 Zuheir Altamimi
2014 Reinhard Dietrich
2015 Geoffrey Blewitt
2016 Srinivas Bettadpur
2017 Isabella Velicogna
2018
2019 Tonie van Dam
2020
2021 Christopher Jekeli
2022 Peter J. G. Teunissen
2023
2024 Jeffrey T. Freymueller
References
Awards of the European Geosciences Union
Awards established in 1998
Geodesy | Vening Meinesz Medal | [
"Mathematics"
] | 311 | [
"Applied mathematics",
"Geodesy"
] |
75,524,438 | https://en.wikipedia.org/wiki/E2%20Linux | E2 Linux is an umbrella name for Linux distributions designed to control digital television receivers (DVB-S, DVB-C, and DVB-T), set-top boxes and IPTV receivers. E2 Linux was originally developed for Dreambox receivers, but after 2010 a number of other manufacturers began shipping devices with E2 Linux, including Formuler, GigaBlue, Octagon, Opticum, Unibox, Vu+, and Zgemma.
History
A modification of the Linux operating system, now called E2 Linux, was developed by a group of enthusiasts in the TuxBox project between 2000 and 2001 for the digital satellite receiver DBox2, which was supplied by the German media group Kirch Group for access to the pay satellite station DF1 (later Premiere, then Sky Deutschland). The receiver was supplied with BetaResearch's Betanova firmware, which was based on Sun's ChorusOS and used Java for the user interface. Its responsiveness was slow and its capabilities limited. At least three user interfaces - Neutrino, Lcars (inspired by Star Trek), and Enigma - were developed as part of the TuxBox project, but KirchPayTV went bankrupt in 2002, ending production of the DBox2 receivers. As early as 2003, however, Dream Multimedia (now Dream Service GmbH) picked up the development and introduced the Dreambox 5600, 5620 and 7000 satellite receivers with a 252 MHz PowerPC processor and IBM STB04500 chips. Dream Multimedia chose the enigma interface for its receiver and named the entire operating system after it. In 2006 it developed a new version called enigma2. At that time, many other manufacturers appeared who did not contribute much to the development but competed with Dream Multimedia on price. The company therefore decided to close further development of the system.
Hardware
Devices designed for Enigma2 (i.e. satellite receivers, set-top boxes and IPTV receivers, often collectively referred to as "box") are equipped with one or more DVB-S, DVB-C and DVB-T tuners (unless it is a pure IPTV receiver), a remote control receiver and an Ethernet and/or Wi-Fi network adapter. One or more decoder card slots are available for receiving encrypted programmes. For storing the operating system, the device is usually equipped with flash memory, and a larger hard disk, SSD, USB flash drive or memory card can be connected or inserted for recording programmes or for playing back files. The device can also use network storage or a disk volume on a personal computer using the Samba or NFS protocol. The system is designed to be controlled by a remote control similar to those used for television sets. A television connected to an Enigma device, usually by HDMI (or SCART in older systems) cable, acts as a multimedia monitor. The device can also usually be connected to a home audio system, usually via an S/PDIF interface.
Software
The central application is Enigma2, which implements a graphical user interface (GUI) for controlling DVB receivers. Since many of the devices running E2 Linux have limited internal and external memory sizes, lightweight versions of Linux tools (BusyBox, dropbear, etc.) are usually used, and the OpenEmbedded (OE) environment is used for building. The configuration of the functions needed for system management is implemented as text dialogs.
The system can be accessed using standard terminal emulation programs, ssh or telnet, file-transfer protocols FTP, SFTP and can act as Samba and NFS server and client.
Plugins with additional features, like Kodi, Chromium , HbbTV, may be available in some E2 Linux distributions.
Current state
In 2020, there are dozens of E2 Linux distributions that differ in enigma2 functionality, additional installed software, plugins, etc. Some of the most well-known include OpenATV, OpenViX, OpenPLi, OpenEight, Black Hole, EGAMI, PurE2. They come in the form of a disk image packaged in a ZIP file. The same format is used for complete backups of the entire system; there is also an option to backup only configuration files. Updates can be performed by using the opkg package manager. Dream multimedia no longer uses the name Enigma for the latest versions of its system, but a new system named Drembox OS. Some receivers support Multiboot - the ability to install multiple distributions or different versions of the current distribution, for feature checking and comparison purposes or as a rescue system in case of problems rather than for routine use.
See also
Enigma (DVB)
Linux on embedded systems
OpenEmbedded
Set-top box
References
Computing platforms
Embedded Linux distributions | E2 Linux | [
"Technology"
] | 985 | [
"Computing platforms"
] |
75,527,230 | https://en.wikipedia.org/wiki/Joanna%20V.%20Clark | Joanna V. Clark is a geoscientist working for the NASA Johnson Space Center, where she is a collaborator on the Sample Analysis at Mars (SAM) and Mars Science Lab (MSL) science teams. Her research includes conducting laboratory experiments to understand better ground and mineral samples acquired by the curiosity rover on Mars.
Education
Clark has an undergraduate degree in geological sciences completed at The State University of New York at Geneseo in 2013, a master's degree in geological sciences from The University of Alabama completed in 2015, and a PhD in geological and earth sciences completed at The University of Houston in 2021.
PhD thesis
In 2019, Clark was awarded a two-year, $285,000 NASA grant to support the work of her thesis in which she studied the effect of temperature on silica formation to understand previous climate conditions on Mars better. To determine whether the planet once contained life, paleoclimatologists study clues left behind in rocks or, in this case, the oxygen composition of silica. Clark's research focused on performing laboratory experiments to form silica at subzero temperatures, which was then used to determine if water had previously been present on the planet. According to her advisor, Tom Lapen, it is rare for a graduate student to receive such major funding as these programs are highly competitive, with top researchers across the U.S. submitting hundreds of proposals.
Career
Mars Science Lab (MSL)
Joanna Clark became a full-time member of the Mars group at the NASA Johnson Space Center through the JETS II Contract, working under Jacobs Solutions Inc. It is within this group that one of their primary science objectives is to assess the habitability of ancient and modern martian environments by using the Curiosity rover through a series of instruments and technologies that include: SAM, CheMin, APXS, ChemCam, DAN, REMS, RAD, MastCam & MAHLI.
Sample Analysis at Mars (SAM)
Clark is a payload uplink lead for the Curiosity rover, in which she delivers commands to collect samples for the SAM instrument to analyze. From there, results are sent back to Earth for her team to further assess past habitability and gather data to use for future exploration projects such as one day sending humans to Mars.
One of Clark's projects for NASA included using mineralogical and chemical data from Curiosity to determine whether the Martian soil found from Rocknest could be used with a water-extraction device. This was accomplished by utilizing the SAM instrument and determining which chemical compounds were included in the Martian soil. From there, the Johnson Space Center replicated a simulant called JSC-Rocknest to run a variety of experiments on, which included heating it to different temperatures to determine its water re-absorption rate and determining its ability to be broken down into compounds needed for liveable conditions. Their findings include a variety of hopeful results necessary to further develop any new advancements for exploring Mars. Since the study, large quantities of JSC-Rocknest have been produced to continue with large-scale applications such as In-Situ Resource Utilization (ISRU) systems and component testing, ISRU plant growth studies, and ISRU habitat studies.
Other NASA Involvement
Clark is a laboratory lead at NASA's Mars, Moon, Meteorite Evolved Gas Analysis (M3EGA) laboratory. Their objective is to conduct thermal and evolved gas analyses of volatile-bearing minerals. These analyses are similar to the data collection that happen during planetary missions that determine whether certain minerals may be present and, if so, in which quantities.
Clark is also a laboratory lead at the Astromaterials Research & Exploration Science (ARES) General Chemical Laboratory. The facility offers a range of equipment to serve the needs of ARES scientists in Research and Curation.
Clark is on the leadership council of "Supporting Women at NASA," a networking group consisting of female scientists and engineers looking to share their passions for planetary sciences among themselves and the community.
References
Mars Exploration Program
American women geologists
NASA people
Geochemists
American geochemists
21st-century American women scientists
Year of birth missing (living people)
Living people
University of Alabama alumni
University of Houston alumni | Joanna V. Clark | [
"Chemistry"
] | 837 | [
"Geochemists",
"American geochemists"
] |
75,527,337 | https://en.wikipedia.org/wiki/Brown%20Friday | Brown Friday is a term commonly addressed to the Friday after Thanksgiving in the United States. The term was coined by plumbers who report a sudden increase in service calls that report clogged drains and broken garbage disposals happening, directly after Thanksgiving.
Vic Fredlund, the service manager of Abacus Plumbing, believes this event to be caused by people "putting materials like starches, fibers, materials, things like that in the garbage disposal." Doyle James, the president of Mr. Rooter Plumbing, blames it on "the grease and the potato peels," and Paul Abrams, a spokesperson for Roto-Rooter also blames it on potato peels, as well as rice, stating: "People continue to peel potatoes over the sink and then push the peels down into the garbage disposal [...]. Rice [is also] consistent with big holiday meal prep," which all tend to clog drains and pipes, especially after Thanksgiving with the large amounts of waste it produces. Additionally, in a large gathering such as Thanksgiving, toilet pipes also tend to be clogged up by large amounts of toilet paper and wipes.
Major plumbing companies in North America report drastic increases in service requests. Mr. Rooter Plumbing report a 50% increase in service calls on Brown Friday. Roto-Rooter reports a 48-50% increase in service calls on Brown Friday. Bell Brothers report a "higher volume of calls."
References
Friday observances
Observances based on the date of Thanksgiving (United States)
Plumbing
Unofficial observances | Brown Friday | [
"Engineering"
] | 319 | [
"Construction",
"Plumbing"
] |
75,527,363 | https://en.wikipedia.org/wiki/Angular%20mechanics | In physics, angular mechanics is a field of mechanics which studies rotational movement. It studies things such as angular momentum, angular velocity, and torque. It also studies more advanced things such as Coriolis force and Angular aerodynamics. It is used in many fields such as toy making, aerospace engineering, and aviation.
Applications
Aviation
In aviation, angular mechanics is used. Propellers spin, which generates angular momentum. Because of the momentum, it directs the air back and keeps the plane up while also propelling it forward. This uses angular mechanics, especially torque and angular momentum.
Toy making
Many toys are made with angular mechanics in mind. These toys include gyroscopes, tops, and yo-yos. When you spin a toy, you apply force to both sides (Push and pull respectively). This makes the top spin. According to newtons third law of motion, the top would continue to spin until a force is acted upon it. Because of all of the forces cancelling out gravity, it will stay upright.
Aerospace engineering
In aerospace engineering, angular mechanics is put to mind. Where the ISS is located, there is around 90% the gravity of the ground. The reason the ISS does not fall down is due to angular momentum.
Equations
In angular mechanics, there are many equations. Most of which explain the nature of rotational movement.
Torque
The equation for torque is very important in angular mechanics. Torque is rotational force and is determined by a cross product. This makes it a pseudovector.
where is torque, r is radius, and is a cross product. Another variation of this equation is:
Where is torque, r is radius, F is force and is the angle between the two vectors.
Angular velocity
The equation for angular velocity is widely used in understanding rotational mechanics.
where is angular velocity and is angle.
Angular acceleration
where is angular acceleration, and is angular velocity
Planetary motion
When planets spin, they generate angular momentum. This does things such as cause the planet to be slightly oval-shaped, and cause deformities in the planet. Another example of angular mechanics in planetary motion is orbiting around a star. Because of the speed of the orbit, they do not go plummeting into their star.
Earth
The earth moves 1667.9239 kilometers per hour around its axis. Because of this, you weigh less on the equator than the poles due to the Coriolis effect. Another thing caused by the Coriolis effect on earth is the deformation of the earth. Because of this, you are farther from the center of the earth on the equator than the poles. The orbital speed of the earth is about approximately 30 (More precisely, 29.80565528) kilometers per second. This causes the earth to perfectly orbit the sun.
Moon
The moon orbits the earth at around a kilometer a second (or more specifically, 0.9204818658 km/s). But it is also tidally locked. It generates enough rotational momentum to be at the exact distance that it rotates as fast as it spins.
History
Angular mechanics has a rich history.
~500 BCE-323 BCE
In ancient Greece, people were found playing with yo-yos. Whilst the ancient Greeks did not know much about angular momentum, they were fascinated by its ability to stand up while spinning.
~1295-1358
Jean Buridan, French philosopher discovered momentum, including angular momentum in his lifetime.
~1642-1727
When Isaac Newton discovered his laws of motion, other people built off his laws to make the laws of rotation.
1743
Inspired by the laws of rotation, John Serson invented the gyroscope in 1743.
Rotational laws
Eulers second law
Eulers second law states that the rate of change of rotational momentum about a point that is fixed at any inertial reference frame is equal to the sum of any external torques acting on that body at that point in space
Newtons laws of motion
Sources:
Newtons laws of motion can translate to rotational laws.
First law
An object at rest tends to remain at rest, but an object in rotational motion will keep rotating unless a force is acted upon it.
Second law
Angular acceleration is equal to the net torque and inversely proportional to the moment of inertia.
Third law
For every action there is an equal and opposite reaction.
See also
Classical mechanics
Kinetics (physics)
Rotation
Circular motion
References
Mechanics | Angular mechanics | [
"Physics",
"Engineering"
] | 885 | [
"Mechanics",
"Mechanical engineering"
] |
74,116,060 | https://en.wikipedia.org/wiki/Sandra%20Llano-Mej%C3%ADa | Sandra Isabel Llano-Mejía (born 1951) is a Colombian multimedia artist. She is considered "a pioneer of video art in Latin America". In the 1970s and 1980s, Llano-Mejía's video art was shown throughout Mexico and the United States. She has an interest in technology in her artwork, such as computers and medical equipment. In the 1970s Llano-Mejía worked in xerox art.
Llano-Mejía attended in Cali, Colombia; followed by studies at Escuela Nacional de Artes Plásticas (ENAP) in Mexico City; National Autonomous University of Mexico; and Metropolitan Autonomous University in Mexico City. Her work can be found in the museum collections at the Museum of Modern Art.
See also
List of Colombian women artists
Marta Minujín
Pola Weiss Álvarez
María Evelia Marmolejo
References
1951 births
Living people
Multimedia artists
Women video artists
People from Cali
Xerox artists
Colombian emigrants to the United States
Colombian emigrants to Mexico
National Autonomous University of Mexico alumni
Universidad Autónoma Metropolitana alumni | Sandra Llano-Mejía | [
"Technology"
] | 217 | [
"Multimedia",
"Multimedia artists"
] |
74,116,880 | https://en.wikipedia.org/wiki/Navajo%20water%20rights | Water rights for the Navajo Nation have been a source of environmental conflict for decades, as Navajo lands have provided energy and water for residents of neighboring states while many of the Navajo do not have electricity or running water in their homes. Beginning in the 1960s, coal mining by Peabody coal at Black Mesa withdrew more than 3 million gallons of water/day from the Navajo aquifer, reducing the number of springs on the reservation. The Navajo Generating Station also consumed about 11 billion gallons of water per year to provide power for the Central Arizona Project that pumps water from Lake Havasu into Arizona.
Native American tribes along the Colorado River were left out of the 1922 Colorado River Compact that divided water among the states, forcing tribes to negotiate settlements with the states for water. The Navajo negotiated water settlements with New Mexico and Utah in 2009 and 2020 respectively, but had not reached an agreement with Arizona in 2023.
On June 22, 2023, the US Supreme Court ruled in Arizona v. Navajo Nation that the federal government of the United States has no obligation to ensure that the Navajo Nation has access to water. The court ruled that the 1868 treaty establishing the Navajo Reservation reserved necessary water to accomplish the purpose of the Navajo Reservation but did not require the United States to take affirmative steps to secure water for the Tribe.
Additionally, environmental crises, such as the 2015 Gold King Mine waste water spill have had lasting impact on the Nation's access to clean water.
Water rights and access
The Navajo reservation is the largest Indian reservation in the US with a population of about 175,000 people. In 2023, about one third of residents did not have running water in their homes.
Water rights to the Colorado River are governed by the 1922 Colorado River Compact that divides the water among western states. Indigenous Nations were left out of this agreement, forcing them to negotiate for water from the states. In 1908, the US Supreme Court ruled in Winters vs United States that Native American water rights should have priority over settler claims, because the federal government established those claims when the reservations were formed.
Beginning in the 1960s, coal mining by Peabody coal at Black Mesa withdrew more than 3 million gallons of water/day from the Navajo aquifer, reducing the number of springs on the reservation. From 1968 until 2019, the Navajo Generating Station consumed 11 billion gallons of water/year to provide power for the Central Arizona Project, which pumps water from Lake Havasu into Arizona.
In 2005, the tribe made a water agreement with the state of New Mexico securing some water rights in the San Juan Basin. Congress approved that agreement in 2009, but the tribe lacked pipeline infrastructure to access that water. The San Juan Generating Station’s water reservoir was sold to the U.S. Bureau of Reclamation in 2023 to provide a reliable and sustainable water supply to Navajo homes and businesses. The reservoir was renamed the Frank Chee Willetto Reservoir.
In 2020, the tribe completed a water settlement with the state of Utah.
In 2023, the tribe still had not completed a settlement with the state of Arizona, and is not receiving their share of Arizona's water under the Colorado River Compact. Arizona has tried to use water access as a way to force the Navajo to make concessions on unrelated issues, and other tribes have also had trouble negotiating water settlements with Arizona.
Arizona v Navajo Nation
The tribe brought a lawsuit against the federal government in 2003, seeking to force the federal government to assess the Nation's water needs and "devise a plan to meet those needs." The states of Nevada, Arizona, and Colorado intervened in the suit to protect their access to water from the Colorado River.
In 2021, the 9th U.S. Circuit Court of Appeals ruled that the tribe could force the government to ensure its access to water.
The suit was decided by the Supreme Court in 2023 in favor of the states. Justice Brett Kavanaugh wrote the majority opinion, and said that the 1868 Treaty of Bosque Redondo between the Navajo Nation and the federal government did not require that the US government secure water access for the Navajo.
Justice Neil Gorsuch wrote the dissenting opinion, and argued that the federal government should identify the water rights that are held for the Navajo Nation and ensure that water had not been misappropriated.
The court affirmed the Navajo Nation's right to intervene in lawsuits related to water claims.
References
Water law in the United States
Water
Environmental ethics
Environmental justice in the United States
Indigenous peoples of North America and the environment
Environmental racism in the United States | Navajo water rights | [
"Environmental_science"
] | 908 | [
"Environmental ethics"
] |
74,120,371 | https://en.wikipedia.org/wiki/Armengaud-Lemale%20gas%20turbine | The Armengaud-Lemale gas turbine was an early experimental turbine engine built by the Société Anonyme des Turbomoteurs at their facility in Saint-Denis, Paris during 1906. The machine is named after the society's founders, Rene Armengaud and Charles Lemale.
The 1906 Armengaud-Lemale gas turbine could sustain its own air compression but was too inefficient to produce useful work. Although it was unsuccessful as a gas turbine, the combustion chamber design from the 1906 machine was later used successfully in torpedo engines.
Design and development
In 1901, Charles Lemale obtained a patent for a gas turbine and in 1903 he founded the Société Anonyme des Turbomoteurs with Rene Armengaud. The society proposed a number of new technologies including hollow turbine blades, combustion reheat and compressor stage inter-cooling.
In 1904 the society built a small proof of concept gas turbine. Air was supplied to an oil fueled combustion chamber by a centrifugal compressor at a pressure of . The air fuel mixture was fired by a hot wire with combustion products cooled by water spray. Exhaust gasses were expanded in a nozzle before acting on a modified de Laval steam turbine with a wheel which ran at 20,000 rpm.
In 1906 the society completed a large gas turbine with three gas compressor casings containing a total of 25 centrifugal impellers. The compressors were designed by Auguste Rateau and manufactured by the Swiss Brown Boveri Company (BBC). These were the first of many centrifugal compressors manufactured by BBC.
Due to the state of metallurgy in 1906, interstage turbine temperatures had to be kept below to avoid damaging turbine wheels. To maintain acceptable temperatures a steady stream of water was injected into the combustion chamber.
Low turbine admission temperatures and the relatively poor efficiency of early centrifugal compressors gave the Armengaud-Lemale gas turbine a low thermal efficiency. In its final form, the Armengaud-Lemale machine was efficient enough to power its own air compressors but could do little else and was not viable as a commercial power source. It was later calculated that to achieve a overall efficiency of just 5% with a compressor efficiency of 68% and a turbine efficiency of 78% would have required a combustion temperature of which was not possible given the technology available in 1906.
Further Developments
Following their work on the Armengaud-Lemale turbine, BBC went onto develop a series of industrial centrifugal compressors and eventually built and tested the world's first gas turbine power station at Neuchâtel, Switzerland in 1939.
The 1906 machine was the last large gas turbine built by the Société Anonyme des Turbomoteurs. The society ceased all work on gas turbines after the death of Rene Armengaud in 1909. The combustion chamber of the 1906 gas turbine was successfully developed, and licensed by the society, for use in naval torpedoes. Kerosene was injected and burned in a compressed air stream increasing the pressure actuating the torpedo's propelling engine. The Armengaud-Lemale combustion chamber was ideal for this application owing to the availability of seawater for cooling.
Performance
Test data published by the Société Anonyme des Turbomoteurs. Run took place with a quoted ambient temperature of .
Overall compressor ratio: 3.85
Compressor discharge temperature:
Combustion temperature:
Interstage turbine temperature:
Exhaust temperature:
Water consumption: per hour
Fuel consumption: per hour
RPM: 4,250
Power output: near zero
Thermal efficiency: 3%
References
Gas compressors
Gas turbines
Brown, Boveri & Cie
Centrifugal-flow gas turbine engines | Armengaud-Lemale gas turbine | [
"Chemistry",
"Technology"
] | 751 | [
"Gas compressors",
"Engines",
"Turbomachinery",
"Gas turbines"
] |
74,121,818 | https://en.wikipedia.org/wiki/Lifting%20boss | Lifting bosses or handling bosses are protrusions intentionally left on stones by masons to facilitate maneuvering the blocks with ropes and levers.
They are an important feature of ancient and classical construction, and were often not cut away, despite having fulfilled their purpose. Sometimes this was the result of a cost-saving measure or a construction halt. Other times bosses were left as a stylistic element, and even if dressed back, a remnant of them was kept to make their existence obvious.
See also
Boss (architecture)
Bossage
References
Further reading
Stonemasonry
Construction
Architecture | Lifting boss | [
"Engineering"
] | 115 | [
"Construction",
"Stonemasonry",
"Architecture"
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74,122,214 | https://en.wikipedia.org/wiki/Lexell%27s%20theorem | In spherical geometry, Lexell's theorem holds that every spherical triangle with the same surface area on a fixed base has its apex on a small circle, called Lexell's circle or Lexell's locus, passing through each of the two points antipodal to the two base vertices.
A spherical triangle is a shape on a sphere consisting of three vertices (corner points) connected by three sides, each of which is part of a great circle (the analog on the sphere of a straight line in the plane, for example the equator and meridians of a globe). Any of the sides of a spherical triangle can be considered the base, and the opposite vertex is the corresponding apex. Two points on a sphere are antipodal if they are diametrically opposite, as far apart as possible.
The theorem is named for Anders Johan Lexell, who presented a paper about it (published 1784) including both a trigonometric proof and a geometric one. Lexell's colleague Leonhard Euler wrote another pair of proofs in 1778 (published 1797), and a variety of proofs have been written since by Adrien-Marie Legendre (1800), Jakob Steiner (1827), Carl Friedrich Gauss (1841), Paul Serret (1855), and Joseph-Émile Barbier (1864), among others.
The theorem is the analog of propositions 37 and 39 in Book I of Euclid's Elements, which prove that every planar triangle with the same area on a fixed base has its apex on a straight line parallel to the base. An analogous theorem can also be proven for hyperbolic triangles, for which the apex lies on a hypercycle.
Statement
Given a fixed base an arc of a great circle on a sphere, and two apex points and on the same side of great circle Lexell's theorem holds that the surface area of the spherical triangle is equal to that of if and only if lies on the small-circle arc where and are the points antipodal to and respectively.
As one analog of the planar formula for the area of a triangle, the spherical excess of spherical triangle can be computed in terms of the base (the angular length of arc and "height" (the angular distance between the parallel small circles
This formula is based on consideration of a sphere of radius , on which arc length is called angle measure and surface area is called spherical excess or solid angle measure. The angle measure of a complete great circle is radians, and the spherical excess of a hemisphere (half-sphere) is steradians, where is the circle constant.
In the limit for triangles much smaller than the radius of the sphere, this reduces to the planar formula.
The small circles and each intersect the great circle at an angle of
Proofs
There are several ways to prove Lexell's theorem, each illuminating a different aspect of the relationships involved.
Isosceles triangles
The main idea in Lexell's geometric proof – also adopted by Eugène Catalan (1843), Robert Allardice (1883), Jacques Hadamard (1901), Antoine Gob (1922), and Hiroshi Maehara (1999) – is to split the triangle into three isosceles triangles with common apex at the circumcenter and then chase angles to find the spherical excess of triangle In the figure, points and are on the far side of the sphere so that we can clearly see their antipodal points and all of Lexell's circle
Let the base angles of the isosceles triangles (shaded red in the figure), (blue), and (purple) be respectively and (In some cases is outside then one of the quantities will be negative.) We can compute the internal angles of (orange) in terms of these angles: (the supplement of and likewise and finally
By Girard's theorem the spherical excess of is
If base is fixed, for any third vertex falling on the same arc of Lexell's circle, the point and therefore the quantity will not change, so the excess of which depends only on will likewise be constant. And vice versa: if remains constant when the point is changed, then so must be, and therefore must be fixed, so must remain on Lexell's circle.
Cyclic quadrilateral
Jakob Steiner (1827) wrote a proof in similar style to Lexell's, also using Girard's theorem, but demonstrating the angle invariants in the triangle by constructing a cyclic quadrilateral inside the Lexell circle, using the property that pairs of opposite angles in a spherical cyclic quadrilateral have the same sum.
Starting with a triangle , let be the Lexell circle circumscribing and let be another point on separated from by the great circle Let
Because the quadrilateral is cyclic, the sum of each pair of its opposite angles is equal, or rearranged
By Girard's theorem the spherical excess of is
The quantity does not depend on the choice of so is invariant when is moved to another point on the same arc of Therefore is also invariant.
Conversely, if is changed but is invariant, then the opposite angles of the quadrilateral will have the same sum, which implies lies on the small circle
Spherical parallelograms
Euler in 1778 proved Lexell's theorem analogously to Euclid's proof of Elements I.35 and I.37, as did Victor-Amédée Lebesgue independently in 1855, using spherical parallelograms – spherical quadrilaterals with congruent opposite sides, which have parallel small circles passing through opposite pairs of adjacent vertices and are in many ways analogous to Euclidean parallelograms. There is one complication compared to Euclid's proof, however: The four sides of a spherical parallelogram are the great-circle arcs through the vertices rather than the parallel small circles. Euclid's proof does not need to account for the small lens-shaped regions sandwiched between the great and small circles, which vanish in the planar case.
A lemma analogous to Elements I.35: two spherical parallelograms on the same base and between the same parallels have equal area.
Proof: Let and be spherical parallelograms with the great circle (the "midpoint circle") passing through the midpoints of sides and coinciding with the corresponding midpoint circle in Let be the intersection point between sides and Because the midpoint circle is shared, the two top sides and lie on the same small circle parallel to and antipodal to a small circle passing through and
Two arcs of are congruent, thus the two curvilinear triangles and each bounded by on the top side, are congruent. Each parallelogram is formed from one of these curvilinear triangles added to the triangle and to one of the congruent lens-shaped regions between each top side and with the curvilinear triangle cut away. Therefore the parallelograms have the same area. (As in Elements, the case where the parallelograms do not intersect on the sides is omitted, but can be proven by a similar argument.)
Proof of Lexell's theorem: Given two spherical triangles and each with its apex on the same small circle through points and construct new segments and congruent to with vertices and on The two quadrilaterals and are spherical parallelograms, each formed by pasting together the respective triangle and a congruent copy. By the lemma, the two parallelograms have the same area, so the original triangles must also have the same area.
Proof of the converse: If two spherical triangles have the same area and the apex of the second is assumed to not lie on the Lexell circle of the first, then the line through one side of the second triangle can be intersected with the Lexell circle to form a new triangle which has a different area from the second triangle but the same area as the first triangle, a contradiction. This argument is the same as that found in Elements I.39.
Saccheri quadrilateral
Another proof using the midpoint circle which is more visually apparent in a single picture is due to Carl Friedrich Gauss (1841), who constructs the Saccheri quadrilateral (a quadrilateral with two adjacent right angles and two other equal angles) formed between the side of the triangle and its perpendicular projection onto the midpoint circle which has the same area as the triangle.
Let be the great circle through the midpoints of and of and let and be the perpendicular projections of the triangle vertices onto The resulting pair of right triangles and (shaded red) have equal angles at (vertical angles) and equal hypotenuses, so they are congruent; so are the triangles and (blue). Therefore, the area of triangle is equal to the area of Saccheri quadrilateral as each consists of one red triangle, one blue triangle, and the green quadrilateral pasted together. (If falls outside the arc then either the red or blue triangles will have negative signed area.) Because the great circle and therefore the quadrilateral is the same for any choice of lying on the Lexell circle the area of the corresponding triangle is constant.
Stereographic projection
The stereographic projection maps the sphere to the plane. A designated great circle is mapped onto the primitive circle in the plane, and its poles are mapped to the origin (center of the primitive circle) and the point at infinity, respectively. Every circle on the sphere is mapped to a circle or straight line in the plane, with straight lines representing circles through the second pole. The stereographic projection is conformal, meaning it preserves angles.
To prove relationships about a general spherical triangle without loss of generality vertex can be taken as the point which projects to the origin. The sides of the spherical triangle then project to two straight segments and a circular arc. If the tangent lines to the circular side at the other two vertices intersect at point a planar straight-sided quadrilateral can be formed whose external angle at is the spherical excess of the spherical triangle. This is sometimes called the Cesàro method of spherical trigonometry, after crystallographer who popularized it in two 1905 papers.
Paul Serret (in 1855, a half century before Cesàro), and independently Aleksander Simonič (2019), used Cesàro's method to prove Lexell's theorem. Let be the center in the plane of the circular arc to which side projects. Then is a right kite, so the central angle is equal to the external angle at the triangle's spherical excess Planar angle is an inscribed angle subtending the same arc, so by the inscribed angle theorem has measure This relationship is preserved for any choice of therefore, the spherical excess of the triangle is constant whenever remains on the Lexell circle which projects to a line through in the plane. (If the area of the triangle is greater than a half-hemisphere, a similar argument can be made, but the point is no longer internal to the angle
Perimeter of the polar triangle
Every spherical triangle has a dual, its polar triangle; if triangle (shaded purple) is the polar triangle of (shaded orange) then the vertices are the poles of the respective sides and vice versa, the vertices are the poles of the sides The polar duality exchanges the sides (central angles) and external angles (dihedral angles) between the two triangles.
Because each side of the dual triangle is the supplement of an internal angle of the original triangle, the spherical excess of is a function of the perimeter of the dual triangle
where the notation means the angular length of the great-circle arc
In 1854 Joseph-Émile Barbier – and independently László Fejes Tóth (1953) – used the polar triangle in his proof of Lexell's theorem, which is essentially dual to the proof by isosceles triangles above, noting that under polar duality the Lexell circle circumscribing becomes an excircle of (incircle of a colunar triangle) externally tangent to side
If vertex is moved along the side changes but always remains tangent to the same circle Because the arcs from each vertex to either adjacent touch point of an incircle or excircle are congruent, (blue segments) and (red segments), the perimeter is
which remains constant, depending only on the circle but not on the changing side Conversely, if the point moves off of the associated excircle will change in size, moving the points and both toward or both away from and changing the perimeter of and thus changing
The locus of points for which is constant is therefore
Trigonometric proofs
Both Lexell () and Euler (1778) included trigonometric proofs in their papers, and several later mathematicians have presented trigonometric proofs, including Adrien-Marie Legendre (1800), Louis Puissant (1842), Ignace-Louis-Alfred Le Cointe (1858), and Joseph-Alfred Serret (1862). Such proofs start from known triangle relations such as the spherical law of cosines or a formula for spherical excess, and then proceed by algebraic manipulation of trigonometric identities.
Opposite arcs of Lexell's circle
The sphere is separated into two hemispheres by the great circle and any Lexell circle through and is separated into two arcs, one in each hemisphere. If the point is on the opposite arc from then the areas of and will generally differ. However, if spherical surface area is interpreted to be signed, with sign determined by boundary orientation, then the areas of triangle and have opposite signs and differ by the area of a hemisphere.
Lexell suggested a more general framing. Given two distinct non-antipodal points and there are two great-circle arcs joining them: one shorter than a semicircle and the other longer. Given a triple of points, typically is interpreted to mean the area enclosed by the three shorter arcs joining each pair. However, if we allow choice of arc for each pair, then 8 distinct generalized spherical triangles can be made, some with self intersections, of which four might be considered to have the same base
These eight triangles do not all have the same surface area, but if area is interpreted to be signed, with sign determined by boundary orientation, then those which differ differ by the area of a hemisphere.
In this context, given four distinct, non-antipodal points and on a sphere, Lexell's theorem holds that the signed surface area of any generalized triangle differs from that of any generalized triangle by a whole number of hemispheres if and only if and are concyclic.
Special cases
Lunar degeneracy
As the apex approaches either of the points antipodal to the base vertices – say – along Lexell's circle in the limit the triangle degenerates to a lune tangent to at and tangent to the antipodal small circle at and having the same excess as any of the triangles with apex on the same arc of As a degenerate triangle, it has a straight angle at (i.e. a half turn) and equal angles
As approaches from the opposite direction (along the other arc of Lexell's circle), in the limit the triangle degenerates to the co-hemispherical lune tangent to the Lexell circle at with the opposite orientation and angles
Half-hemisphere area
The area of a spherical triangle is equal to half a hemisphere (excess if and only if the Lexell circle is orthogonal to the great circle that is if arc is a diameter of circle and arc is a diameter of
In this case, letting be the point diametrically opposed to on the Lexell circle then the four triangles and are congruent, and together form a spherical disphenoid (the central projection of a disphenoid onto a concentric sphere). The eight points are the vertices of a rectangular cuboid.
Related concepts and results
Spherical parallelogram
A spherical parallelogram is a spherical quadrilateral whose opposite sides and opposite angles are congruent It is in many ways analogous to a planar parallelogram. The two diagonals and bisect each-other and the figure has 2-fold rotational symmetry about the intersection point (so the diagonals each split the parallelogram into two congruent spherical triangles, and if the midpoints of either pair of opposite sides are connected by a great circle , the four vertices fall on two parallel small circles equidistant from it. More specifically, any vertex (say of the spherical parallelogram lies at the intersection of the two Lexell circles ( and ) passing through one of the adjacent vertices and the points antipodal to the other two vertices.
As with spherical triangles, spherical parallelograms with the same base and the apex vertices lying on the same Lexell circle have the same area; see above. Starting from any spherical triangle, a second congruent triangle can be formed via a (spherical) point reflection across the midpoint of any side. When combined, these two triangles form a spherical parallelogram with twice the area of the original triangle.
Sorlin's theorem (polar dual)
The polar dual to Lexell's theorem, sometimes called Sorlin's theorem after A. N. J. Sorlin who first proved it trigonometrically in 1825, holds that for a spherical trilateral with sides on fixed great circles (thus fixing the angle between them) and a fixed perimeter (where means the length of the triangle side the envelope of the third side is a small circle internally tangent to and externally tangent to the excircle to trilateral Joseph-Émile Barbier later wrote a geometrical proof (1864) which he used to prove Lexell's theorem, by duality; see above.
This result also applies in Euclidean and hyperbolic geometry: Barbier's geometrical argument can be transplanted directly to the Euclidean or hyperbolic plane.
Foliation of the sphere
Lexell's loci for any base make a foliation of the sphere (decomposition into one-dimensional leaves). These loci are arcs of small circles with endpoints at and on which any intermediate point is the apex of a triangle of a fixed signed area. That area is twice the signed angle between the Lexell circle and the great circle at either of the points or see above. In the figure, the Lexell circles are in green, except for those whose triangles' area is a multiple of a half hemisphere, which are black, with area labeled; see above.
These Lexell circles through and are the spherical analog of the family of Apollonian circles through two points in the plane.
Maximizing spherical triangle area subject to constraints
In 1784 Nicolas Fuss posed and solved the problem of finding the triangle of maximal area on a given base with its apex on a given great circle Fuss used an argument involving infinitesimal variation of but the solution is also a straightforward corollary of Lexell's theorem: the Lexell circle through the apex must be tangent to at
If crosses the great circle through at a point , then by the spherical analog of the tangent–secant theorem, the angular distance to the desired point of tangency satisfies
from which we can explicitly construct the point on such that has maximum area.
In 1786 Theodor von Schubert posed and solved the problem of finding the spherical triangles of maximum and minimum area of a given base and altitude (the spherical length of a perpendicular dropped from the apex to the great circle containing the base); spherical triangles with constant altitude have their apex on a common small circle (the "altitude circle") parallel to the great circle containing the base. Schubert solved this problem by a calculus-based trigonometric approach to show that the triangle of minimal area has its apex at the nearest intersection of the altitude circle and the perpendicular bisector of the base, and the triangle of maximal area has its apex at the far intersection. However, this theorem is also a straightforward corollary of Lexell's theorem: the Lexell circles through the points antipodal to the base vertices representing the smallest and largest triangle areas are those tangent to the altitude circle. In 2019 Vincent Alberge and Elena Frenkel solved the analogous problem in the hyperbolic plane.
Steiner's theorem on area bisectors
In the Euclidean plane, a median of a triangle is the line segment connecting a vertex to the midpoint of the opposite side. The three medians of a triangle all intersect at its centroid. Each median bisects the triangle's area.
On the sphere, a median of a triangle can also be defined as the great-circle arc connecting a vertex to the midpoint of the opposite side. The three medians all intersect at a point, the central projection onto the sphere of the triangle's extrinsic centroid – that is, centroid of the flat triangle containing the three points if the sphere is embedded in 3-dimensional Euclidean space. However, on the sphere the great-circle arc through one vertex and a point on the opposite side which bisects the triangle's area is, in general, distinct from the corresponding median.
Jakob Steiner used Lexell's theorem to prove that these three area-bisecting arcs (which he called "equalizers") all intersect in a point, one possible alternative analog of the planar centroid in spherical geometry. (A different spherical analog of the centroid is the apex of three triangles of equal area whose bases are the sides of the original triangle, the point with as its spherical area coordinates.)
Spherical area coordinates
The barycentric coordinate system for points relative to a given triangle in affine space does not have a perfect analogy in spherical geometry; there is no single spherical coordinate system sharing all of its properties. One partial analogy is spherical area coordinates for a point relative to a given spherical triangle
where each quantity is the signed spherical excess of the corresponding spherical triangle These coordinates sum to and using the same definition in the plane results in barycentric coordinates.
By Lexell's theorem, the locus of points with one coordinate constant is the corresponding Lexell circle. It is thus possible to find the point corresponding to a given triple of spherical area coordinates by intersecting two small circles.
Using their respective spherical area coordinates, any spherical triangle can be mapped to any other, or to any planar triangle, using corresponding barycentric coordinates in the plane. This can be used for polyhedral map projections; for the definition of discrete global grids; or for parametrizing triangulations of the sphere or texture mapping any triangular mesh topologically equivalent to a sphere.
Euclidean plane
The analog of Lexell's theorem in the Euclidean plane comes from antiquity, and can be found in Book I of Euclid's Elements, propositions 37 and 39, built on proposition 35. In the plane, Lexell's circle degenerates to a straight line (which could be called Lexell's line) parallel to the base.
Elements I.35 holds that parallelograms with the same base whose top sides are colinear have equal area. Proof: Let the two parallelograms be and with common base and and on a common line parallel to the base, and let be the intersection between and Then the two top sides are congruent so, adding the intermediate segment to each, Therefore the two triangles and have matching sides so are congruent. Now each of the parallelograms is formed from one of these triangles, added to the triangle with the triangle cut away, so therefore the two parallelograms and have equal area.
Elements I.37 holds that triangles with the same base and an apex on the same line parallel to the base have equal area. Proof: Let triangles and each have its apex on the same line parallel to the base Construct new segments and congruent to with vertices and on The two quadrilaterals and are parallelograms, each formed by pasting together the respective triangle and a congruent copy. By I.35, the two parallelograms have the same area, so the original triangles must also have the same area.
Elements I.39 is the converse: two triangles of equal area on the same side of the same base have their apexes on a line parallel to the base. Proof: If two triangles have the same base and same area and the apex of the second is assumed to not lie on the line parallel to the base (the "Lexell line") through the first, then the line through one side of the second triangle can be intersected with the Lexell line to form a new triangle which has a different area from the second triangle but the same area as the first triangle, a contradiction.
In the Euclidean plane, the area of triangle can be computed using any side length (the base) and the distance between the line through the base and the parallel line through the apex (the corresponding height). Using point as the apex, and multiplying both sides of the traditional identity by to make the analogy to the spherical case more obvious, this is:
The Euclidean theorem can be taken as a corollary of Lexell's theorem on the sphere. It is the limiting case as the curvature of the sphere approaches zero, i.e. for spherical triangles as which are infinitesimal in proportion to the radius of the sphere.
Hyperbolic plane
In the hyperbolic plane, given a triangle the locus of a variable point such that the triangle has the same area as is a hypercycle passing through the points antipodal to and which could be called Lexell's hypercycle. Several proofs from the sphere have straightforward analogs in the hyperbolic plane, including a Gauss-style proof via a Saccheri quadrilateral by Barbarin (1902) and Frenkel & Su (2019), an Euler-style proof via hyperbolic parallelograms by Papadopoulos & Su (2017), and a Paul Serret-style proof via stereographic projection by Shvartsman (2007).
In spherical geometry, the antipodal transformation takes each point to its antipodal (diametrically opposite) point. For a sphere embedded in Euclidean space, this is a point reflection through the center of the sphere; for a sphere stereographically projected to the plane, it is an inversion across the primitive circle composed with a point reflection across the origin (or equivalently, an inversion in a circle of imaginary radius of the same magnitude as the radius of the primitive circle).
In planar hyperbolic geometry, there is a similar antipodal transformation, but any two antipodal points lie in opposite branches of a double hyperbolic plane. For a hyperboloid of two sheets embedded in Minkowski space of signature known as the hyperboloid model, the antipodal transformation is a point reflection through the center of the hyperboloid which takes each point onto the opposite sheet; in the conformal half-plane model it is a reflection across the boundary line of ideal points taking each point into the opposite half-plane; in the conformal disk model it is an inversion across the boundary circle, taking each point in the disk to a point in its complement. As on the sphere, any generalized circle passing through a pair of antipodal points in hyperbolic geometry is a geodesic.
Analogous to the planar and spherical triangle area formulas, the hyperbolic area of the triangle can be computed in terms of the base (the hyperbolic length of arc and "height" (the hyperbolic distance between the parallel hypercycles
As in the spherical case, in the small-triangle limit this reduces to the planar formula.
Notes
References
Eponymous theorems of geometry
Theorems about triangles and circles
Area
Spherical trigonometry
Articles containing proofs | Lexell's theorem | [
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74,122,318 | https://en.wikipedia.org/wiki/Ecology%20block | An ecology block, also known as an eco-block or ecoblock, is a type of recycled concrete block used to make retaining walls. Ecology blocks are manufactured using concrete left over from other construction processes. A cross-section of an eco-block typically measures square, with block lengths ranging from to . One block weighs between and .
Uses
Ecology blocks are marketed for construction of retaining walls; they have grooves on the top and bottom to facilitate vertical stacking. They are used for storage of bulk materials and other modular construction projects where permanent structures are not needed. They have also been used as a temporary fix for a critical road in Skagit County, Washington, that had been damaged by floods. Following the September 11 attacks, at the Hanford Site's Plutonium Finishing Plant, eco-blocks and Jersey barriers were used to create a barrier against vehicular attack. The Seattle Police Department used eco-blocks to construct walls around their East Precinct building while the Capitol Hill Organized Protest was established nearby.
Hostile architecture
In response to homelessness in Seattle, several Seattle businesses and residents have deployed eco-blocks as hostile architecture in residential areas and outside of businesses, with the intention of discouraging homeless encampments and recreational vehicle (RV) parking by homeless persons who live in RVs. City law prohibits the use of eco-blocks on city streets, but as of August 1, 2022, compared with hundreds of eco-blocks deployed in the city, only 25 property and business owners have received warnings, and none have been fined. Eco-blocks are particularly popular in industrial areas of Seattle, the only areas where RVs have been allowed to park legally for up to 72 hours at a time. The Seattle Times reported in July 2022 that "a significant portion of public parking in Georgetown has been blocked" by ecology blocks. The blocks have also impeded delivery trucks, which cannot park between them to unload goods.
Seattle eco-block purchasers were attracted to eco-blocks' low cost, about US$20 per block, and the need for special equipment to remove them. In April 2023, the city removed some eco-blocks that abutted a city park that had been popular with homeless campers, but did not remove the blocks in public streets adjacent to a nearby Fremont Brewing facility owned by Sara Nelson, a member of the Seattle City Council, and her husband Matt Lincecum.
Safety concerns
In February 2012, a 56-year-old heavy equipment operator in Washington state died after being crushed by an approximately eco-block that was part of a wall used to subdivide a tank being used for fertilizer storage. The Washington State Department of Labor and Industries identified "Lack of training regarding the dangers of working around bulk material and
ecology blocks" and "Possible destabilization of block wall due to granular material leaking between the blocks" as contributing factors to the incident, and noted that the employer created a training program about eco-block safety after the incident.
When constructing a retaining wall from eco-blocks, a stable foundation is still required. In July 2015, a 70-year-old man in Washington died after an ecology block wall under construction on a sand foundation collapsed, and his legs were crushed by a block.
See also
Jersey barrier, a similarly sized concrete block used for vehicle traffic control
References
External links
Concrete
Homelessness in the United States | Ecology block | [
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] | 684 | [
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74,123,001 | https://en.wikipedia.org/wiki/Eocronartiaceae | The Eocronartiaceae are a family of fungi in the class Pucciniomycetes. Species in the family have auricularioid basidia (tubular with lateral septa) and are typically plant parasites on ferns and mosses.
References
Pucciniomycotina
Basidiomycota families | Eocronartiaceae | [
"Biology"
] | 66 | [
"Fungus stubs",
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74,123,171 | https://en.wikipedia.org/wiki/Stefan%20Raunser | Stefan Raunser (born 1976 in Landau in der Pfalz, Germany) is a German scientist and structural biologist specializing in membrane proteins, the cytoskeleton, toxins, and sarcomere structural biochemistry. Since 2014, he has been a director at the Max Planck Institute of Molecular Physiology in Dortmund, Germany.
Education and career
Raunser studied biology and chemistry at the Johannes Gutenberg-Universität Mainz and completed his Ph.D. in biochemistry at the Goethe University Frankfurt in 2004, under the supervision of Prof. Werner Kühlbrandt at the Max Planck Institute of Biophysics in Frankfurt/Main.
He continued his research as a postdoctoral researcher at Harvard Medical School in Boston, USA, working with Thomas Walz from 2005 to 2008. He then became an "Emmy Noether group leader" at the Max Planck Institute of Molecular Physiology in Dortmund, serving in that position from 2008 to 2013. In 2014, Raunser held the Einstein Professorship for Membrane Biochemistry at Free University of Berlin from January to June before assuming his current role as a director at the Max Planck Institute of Molecular Physiology. In 2015, he became an honorary professor at the University of Duisburg-Essen, and later that same year, he became an adjunct professor at Technical University of Dortmund.
Research and selected publications
The Raunser lab specializes in structural biochemistry, they employ and develop methods in CryoEM and CryoET to conduct research and uncover the molecular mechanisms in different aspects of cell biology.
Tc toxin complexes
In the field of Tc toxins, tripartite ABC-type toxins from Photorhabdus luminescens and other bacteria that are used by the bacteria as virulence factors, his research has focused on molecular mechanisms involved in toxin activation, toxin release, receptor binding, membrane permeation, protein translocation, and intoxication. His group published a movie of the intoxication process. His work on Tc toxins has revealed their potential as customisable molecular syringes for delivering proteins across membranes, opening up possibilities for biotechnological and biomedical applications.
Software and hardware development in cryoEM/cryoET
The Raunser lab has contributed to developments in cryoEM image processing and cryoET hardware development. They developed SPHIRE (together with Pawel Penczek), which evolved later into TranSPHIRE. The program offers an easy-to-use and versatile image processing suite for the single particle analysis of protein complexes in CryoEM. The group has also developed other software tools, such as SPHIRE-crYOLO and TomoTwin, for automatic particle picking in cryoEM and cryoET. On the CryoET front, the group has developed a streamlined workflow for automated cryo-focused ion beam milling for the analysis of vitrified samples by electron cryo tomography.
Structural biochemistry of the cytoskeleton and muscle contraction
Single particle approach
Raunser's group has increased the resolution limits of single particle cryoEM reconstructions of muscle and cytoskeletal proteins, including actin filaments (F-actin), actin filaments in complex with actin-binding proteins, toxins and ligands, the actin-tropomyosin complex, and the actomyosin complex. The lab has determined the cryoEM structures of F-actin at ~2.2 Å resolution, allowing for the first time the direct visualisation of water molecules in the structure and giving atomic insight into ATP hydrolysis in F-actin and phosphate release from the filament after hydrolysis.
Tomography approach
Raunser's group has revealed the three-dimensional organization of the sarcomere in situ, resolving the molecular organization of myosin, alpha-actinin-1, and additional sarcomeric components. The group also determined the first structure of native nebulin bound to actin thin filaments within intact sarcomeres at 4.5 Å resolution, and has successfully obtained the world's first high-resolution 3D image of the myosin thick filament in its natural cellular environment.
Structural biochemistry of membrane proteins
Raunser's group has made significant contributions to understanding the structures of key proteins involved in cell signaling, such as the rabbit ryanodine receptor 1 and the TRPC4 channel, as well as the Drosophila's Slowpoke (Slo) potassium channel. This research has provided insights into the regulatory mechanisms and revealed potential target sites for drug development.
Fellowships and awards (selection)
Member of the North Rhine-Westphalian Academy of Sciences and Arts (2022)
German National Academy of Sciences Leopoldina Member (2019)
EMBO Member (2018)
Einstein Professorship of the Einstein Foundation Berlin (2013)
Member of the "Junges Kolleg" (Academy of Sciences and Arts of Northrhine-Westfalia) (2011–2014)
Emmy-Noether Fellowship German Research Foundation (DFG) (2008–2013)
Fellow of the German National Academy of Sciences Leopoldina (2007–2008)
References
External links
1976 births
Living people
German biochemists
Max Planck Institute directors
European Research Council grantees
21st-century German biologists
Johannes Gutenberg University Mainz alumni
Goethe University Frankfurt alumni
Science teachers
European Molecular Biology Organization
Members of the German National Academy of Sciences Leopoldina
Structural biologists
Max Planck Society people
People from Rhineland-Palatinate
Harvard Medical School people | Stefan Raunser | [
"Chemistry"
] | 1,115 | [
"Structural biologists",
"Structural biology"
] |
74,123,417 | https://en.wikipedia.org/wiki/Fothergillian%20Medal | The Fothergillian Medal is awarded by the Medical Society of London since 1787.
The first recipient was William Falconer. It was awarded to Edward Jenner in 1803.
References
Medicine awards | Fothergillian Medal | [
"Technology"
] | 41 | [
"Science and technology awards",
"Medicine awards"
] |
74,123,635 | https://en.wikipedia.org/wiki/Kenneth%20E.%20Goodson | Kenneth Eugene Goodson (born August 1, 1967) is an American mechanical engineer and academic at Stanford University. He serves as Davies Family Provostial Professor within the university, as well as Senior Associate Dean for Faculty and Academic Affairs within its School of Engineering.
Early life
According to Who's Who in the World, Goodson was born in Lafayette, Indiana on August 1, 1967.
Education
Goodson has received four academic degrees from the Massachusetts Institute of Technology (MIT): two Bachelors of Science in 1989 (one in mechanical engineering and another in music), a Master of Science in 1991 (in mechanical engineering), and a Doctor of Philosophy in 1993 (also in mechanical engineering).
Career
From 1993 to 1994, he worked for Daimler-Benz AG in Germany as a visiting materials scientist. He has been employed at Stanford since 1994 as a professor in the mechanical engineering department. By courtesy, he also holds a professorship in the materials science & engineering department. Starting in 2008, he was the vice chair of mechanical engineering, and from 2013 to 2019, he held the Robert Bosch Chairman position in the department. Additionally, since 2014, he has held the Davies Family Professorship.
He is the principal investigator of the Stanford NanoHeat Lab, and is also an affiliated faculty member of Stanford Bio-X.
Goodson is a fellow of the American Association for the Advancement of Science, American Society of Mechanical Engineers, Institute of Electrical and Electronics Engineers, American Physical Society, and National Academy of Inventors. He is also an elected member of the National Academy of Engineering (class of 2020).
Recognition
Goodson appears in the 35th through 38th editions of American Men and Women of Science.
Personal life
Goodson moonlights as a baritone soloist in oratorio, and has held voice fellowships from the Tanglewood Music Festival and a Sudler Prize for Arts Achievement (conferred by MIT in 1989). He also posts about woodworking and cycling to his Instagram and Strava accounts, respectively. His wife, Laura Dahl, is a pianist who plays with the Stanford music faculty.
Goodson has also been noted as a cellist.
Notes
References
External links
Kenneth Goodson on Stanford Profiles
1967 births
People from Lafayette, Indiana
Energy engineers
American mechanical engineers
Engineers from California
Massachusetts Institute of Technology alumni
Stanford University Department of Mechanical Engineering faculty
Members of the United States National Academy of Engineering
Fellows of the American Association for the Advancement of Science
Fellows of the American Society of Mechanical Engineers
Fellows of the IEEE
Fellows of the American Physical Society
Fellows of the National Academy of Inventors
Living people | Kenneth E. Goodson | [
"Engineering"
] | 514 | [
"Energy engineering",
"Energy engineers"
] |
74,125,196 | https://en.wikipedia.org/wiki/Burnham%20Plan%20of%20Manila | The Burnham Plan of Manila is a popular name for Report on proposed improvements at Manila and Manila, P.I., plan of proposed improvements, a 1905 report and map by Daniel Burnham and Pierce Anderson which detail the plan for the city of Manila. It proposed developments based on the characteristics of the city and is patterned after the cities of Naples, Paris, and Venice.
The plan was at the request of then-Philippine Governor-General William Howard Taft, four years before Burnham published the more known Plan of Chicago where the plan also appeared along with plans for Washington, D.C., Cleveland, and San Francisco.
There have been efforts to revive the implementation of the plan throughout the years after not being completely realized because of the establishment of Quezon City in 1939 as the new capital and the effects of the World War II including the merging of Manila with nearby cities forming the city of Greater Manila in 1942 and the Battle of Manila in 1945. The plan is often a subject of discussions in the issue of urban planning in the Philippines.
Background
At the turn of 20th century, the Philippines was conquered by the United States from Spain, along with Cuba, Puerto Rico, and Guam. The American colonial government wanted to "modernize" the capital city of their newly acquired territory, and the mountain city of Baguio, which was designated as the summer capital.
William Howard Taft suggested to Philippine Commission member William Cameron Forbes to hire a landscape architect for the task, leading to Forbes initially eyeing Frederick Law Olmsted, Jr. Olmstead, however, was unavailable and the task was eventually given to Daniel Burnham. Other architects who showed interest and was considered for the job included Charles Follen McKim.
Burnham, along with a designer from his firm, Pierce Anderson, arrived in Manila on December 7, 1904, and studied the layout and the environment at the time of the cities of Manila and Baguio for almost a month. The two then went back to the United States where he worked on drawing out the plans for the two cities and completed it by June 1905. It was eventually approved by the U.S. Congress a year later.
Aspects of the plan
The plan focused on five major points:
Development of waterfront, parks, and parkways
The plan suggests utilizing the city's resources, such as the river and ocean bay, for recreation and refreshment to mitigate the intense heat caused by Manila's climate.
One key aspect of the proposal is the creation of a continuous parkway along the bay front, extending from the existing Luneta to Cavite, and possibly further north. Private portions of the bay front would be reclaimed for public use. The boulevard would feature roadways, tramways, a bridle path, plants, and sidewalks, providing protection from the elements with strategically planted palms, bamboo, and mango trees which "adds mystery" and enhances the value of the ocean and sky. Additionally, shaded drives along the banks of the Pasig River, extending from the city to Fort McKinley and beyond to the lake, are also considered in the plan.
The existing Luneta, covered by the Government group, would be replaced by a new Luneta placed further out in the bay, preserving its unobstructed view of the sea on its westward side while trees would enclose the other three sides to provide sun protection and offer glimpses of the bay through the foliage. The proposal recognizes the importance of parks and open spaces in enhancing the beauty and function of buildings. The proposal includes creating small park spaces throughout the city, such as plazas, circles, esplanades, and parkway boulevards which would provide suitable locations for future important buildings. Meanwhile, nine bigger parks evenly distributed in Manila would offer facilities for outdoor activities and connected by green parkway boulevards.
The plan suggests incorporating water elements in Manila's parks, inspired by Rome's use of fountains and water features. These could include decorative fountains, reflecting pools, and small cascades. Water features serve both aesthetic and practical purposes, adding tranquility and beauty to the parks while mitigating heat. The sound and sight of flowing water create a calming atmosphere, and the evaporation of water helps cool the surrounding air, providing relief from high temperatures.
Updated street system
The plan aims to modify the old quarter of town while keeping the street arrangement mostly unchanged. It emphasizes starting early to avoid rising costs and utilizes the low real estate values in Manila. The first step involves establishing new street lines and opening some streets immediately, while others may be opened gradually.
The plan also addresses the preservation of the old walls surrounding the Intramuros, suggesting that openings be made through the massive projecting bastions for roadways. The existing moat is proposed to be filled and leveled to create sunken panels for green spaces.
The outer districts of the city are provided with a street system that avoids north-south or east-west orientation, instead favoring fan-shaped grouping of radiating streets and diagonal arteries for direct communication. The plan also suggests wider avenues with park-like connections and ample shade. The overall goal is to leave the old city streets untouched, improve the setting of the old walls, and create a street system that ensures sunlight, accessibility, and efficient traffic flow. The importance of future needs and the example of Washington, D.C., are highlighted as reasons for the proposed plan's scale and foresight.
Location of building sites
The Government or National Group, which includes the Capitol Building and Department Buildings, is located on the present Camp Wallace and adjacent land back of Calle Nozelada. The buildings are arranged in a hollow square formation, opening westward toward the sea. The eastern front of the Capitol faces a semi-circular plaza, which serves as a central hub connecting the street system to all parts of the city, ensuring the Capitol, the symbol of the nation's power and the center of government activities, is easily accessible from all sides.
South of the main group is the Courthouse. To the north, along Malecón Drive leading to the Bridge of Spain, are area allocated for semi-public buildings such as libraries, museums, and permanent exposition buildings. Behind these buildings are some of the proposed athletic fields. The road ends in a central circle with three important bridges over the Pasig River. Post Office will be relocated south of its current temporary site, requiring riverfront access for easy mail transportation.
A proposed passenger railway station, centrally located in Greater Manila, is connected to the Government center through one of the radiating arteries. The location takes advantage of the bend in the Pasig River, allowing for the development of a terminal property without causing significant disruptions to traffic.
The Municipal Group will be around Plaza McKinley, enlarging the plaza by adding the block with the unfinished Spanish building. The group, which includes Ayuntamiento, and the proposed Custom House, Board of Trade, and Commercial Museum, extends to the waterfront where a special pier is proposed as the main water gate of Manila.
The Governor-General's residence is suggested to be located in the bay outside the boulevard on new-made land, facing an esplanade that extends through the Malate military reservation. The passage also suggests a series of city clubs south of the Governor-General's residence, a country club south of the city limits, and a hotel near Luneta Park. Santa Mesa Heights is considered suitable for schools or a university, while the high ground north and east of the city is suggested for parks and other semi-public institutions.
Development of water transportation
The plan highlights the importance of preserving and developing the estero system, despite their initial unfavorable conditions, as they are valuable for transportation purposes. It suggests widening, dredging, and providing masonry banks for the esteros to enhance their usefulness for freight handling. The development of estero connections is also proposed to reduce the risk of river overflow.
The plan also discusses the need for railroad facilities to support a new port. It suggests two options for the railroad approach: one from the north side, which already exists but requires bridging the Pasig River, and another from the south side, which would cut through the city and require elevated tracks. The plan argues that a drawbridge over the Pasig River would be a more feasible option despite potential hindrances to navigation and reduced river frontage value. It further mentions the possibility of an additional harbor north of the river to accommodate the new port, which would require extending the existing channel.
Additionally, the it emphasizes the aesthetic and practical benefits of establishing shaded drives and open quays along the riverbanks, as well as the public use of these areas.
Summer resorts
Manila needs accessible summer resorts on high ground due to its climate. The plan suggests that locations near Manila, such as the low hills on the east, the mountains of Mariveles, and the hill country around Laguna de Bay, could serve as convenient options for these resorts. This would provide government employees and their families with a change of air without the need for extensive travel or separation.
Implementation
See also
Burnham Plan of Chicago
Frost Plan of Quezon City
References
External links
Plan of Manila in Plan of Chicago on Encyclopedia of Chicago
Report of the Philippine Commission to the Secretary of War, Part 1
Manila, P.I., plan of proposed improvements map on Stanford Libraries
Urban planning in the Philippines
City plans
Landscape architecture | Burnham Plan of Manila | [
"Engineering"
] | 1,895 | [
"Landscape architecture",
"Architecture"
] |
74,127,498 | https://en.wikipedia.org/wiki/Arsene%20Tema%20Biwole | Arsene Tema Biwole is a cameroonian nuclear engineer and plasma physicist at the Massachusetts Institute of Technology (MIT).
Biography
Early life an education
Arsene Tema Biwole was born on June 15, 1992, at the "Camp Bamoun" - built during German colonisation - in Bafoussam, western Cameroon.
Premature and ill during his childhood, he and his brothers were raised by a single and modest mother. Arsene studied Newtonian physics in science books at home without electricity, using the light of a lamp.
He studied nuclear engineering at the Polytechnic School of Turin, becoming the only Cameroonian engaged in this course.
In April 2017, with a grant from the United States Department of Energy, he continued his research for a Master's thesis in San Diego, California at General Atomics. Thus working in the Fusion Theory Group of this company.
Scientific career
In 2017, Arsene Tema Biwole participated in the 59th Meeting of the American Physical Society Division of plasma physics with General atomics. Thus becoming the first Cameroonian in history to both join General Atomics and the Division of Plasma Physics of the American physical Society.
He holds a Doctorate in Physics, obtained at the École Polytechnique Fédérale de Lausanne, titled as follows : "Measuring the electron energy distribution in tokamak plasmas from polarized electron cyclotron radiation".
In June 2023, Arsene Tema Biwole joined the Massachusetts Institute of Technology (MIT), to work for the SPARC tokamak, operated by Commonwealth Fusion Systems in collaboration with the Massachusetts Institute of Technology (MIT) Plasma Science and Fusion Center (PSFC).
Honors and distinctions
Arsene Tema Biwole was cited by Jeune Afrique in 2018, as one of the most promising African scientists.
In 2020, Arsene Tema Biwole won the Youth Excellence Prize in Cameroon and is designated Ambassador of the Youth Connekt Cameroon project.
During a popular poll carried out by the online information platform Afrik-inform, Arsene Tema Biwole was designated as the favorite Cameroonian personality in the diaspora for the year 2020.
From January to February 2021, he travelled through high schools and universities in Cameroon to promote science and encourage vocations among the youth.
On February 10, 2021, Arsene Tema Biwole was cited by Paul Biya, President of the Republic of Cameroon, as a role model for the youth.
In February 2021, Arsene Tema Biwole received, during a public address, congratulations and encouragement from Maurice Kamto for his ambitions and projects for Africa and Humanity,.
Arsene Tema Biwole was the guest of "Actualités Hebdo", a weekly news program of CRTV on February 14, 2021. During the program, Arsene discussed the nuclear perspectives in Africa and the issue of electrification in Cameroon.
In March 2023, Arsene Tema Biwole defended his Doctorate thesis in physics at the École Polytechnique Fédérale de Lausanne. Thesis which was unanimously proposed by the jury for the EPFL Doctoral program thesis prize.
Honors
EPFL Doctoral Program Thesis Distinction, 2023, Nominee.
Excellence in Africa Ambassador of the Federal Polytechnic School of Lausanne.
Knight of the Order of Cameroonian Merit by decree of August 31, 2021, signed by the President of the Republic of Cameroon.
Banca Sella research award, 2016.
EDISU Piemonte super merit student prize, 2012.
Politecnico di Torino Distinguished academic achievement award, 2012.
Notes and references
See also
Henri Hogbe Nlend
1992 births
Living people
Nuclear engineers
Plasma physicists
Cameroonian engineers
People from Bafoussam
École Polytechnique Fédérale de Lausanne alumni
Massachusetts Institute of Technology people | Arsene Tema Biwole | [
"Physics"
] | 767 | [
"Plasma physicists",
"Plasma physics"
] |
74,127,943 | https://en.wikipedia.org/wiki/2023%20Yellowstone%20River%20train%20derailment | The Yellowstone River bridge collapse was a train derailment that occurred on June 24, 2023, near Columbus, Montana, United States. A bridge that crosses the Yellowstone River collapsed, causing several cars of a freight train carrying hazardous materials to fall into the water below. The incident resulted in environmental concerns and internet service disruptions in the state.
The bridge was part of the Montana Rail Link (MRL) network, a privately owned regional railroad that operates over 900 miles of track in Montana and Idaho. The train involved in the derailment was carrying hot asphalt and molten sulfur, which are both flammable. Sulfur is used in phosphate fertilizer production and for direct soil supplement. Hot sulfur burns easily, producing toxic sulfur dioxide. The train crew was safe and no injuries were reported.
Collapse
The collapse occurred around 6 a.m. local time on June 24, 2023. The cause of the collapse is under investigation, but some experts have suggested that repeated years of heavy river flows may have eroded the river bottom and weakened the bridge structure. The adjacent Twin Bridges Road Bridge constructed in 1931 was demolished in 2021 after decades of riverbed bridge scour had undermined its concrete piers and the Montana Department of Transportation had determined it was in danger of collapse. The river was swollen with recent heavy rains at the time of the derailment.
Aftermath
The collapse triggered an emergency response from local, state and federal agencies. Officials shut down drinking water intakes downstream while they evaluated the danger after the derailment. The Yellowstone County Disaster and Emergency Services asked residents to conserve water and implemented precautions at water treatment plants, irrigation districts and industrial companies. The Montana Department of Environmental Quality said it was monitoring the water quality and potential impacts to fish and wildlife. An Associated Press reporter witnessed a yellow substance coming out of some of the tank cars.
The collapse also took out a fiber-optic cable providing internet service to many customers in the state, including the high-speed provider Global Net. The company said it was working to restore service as soon as possible. Montana Gov. Greg Gianforte tweeted that he was monitoring the situation and that the state was standing by to support MRL and county officials.
MRL said it was committed to addressing any potential impacts and working to understand the reasons behind the crash.
References
June 2023 events in the United States
2023 disasters in the United States
Miamisburg train derailment
Derailments in the United States
Railway accidents and incidents in Montana
2023 in Montana
Stillwater County, Montana
Yellowstone River | 2023 Yellowstone River train derailment | [
"Technology"
] | 513 | [
"Railway accidents and incidents",
"Rail accident stubs"
] |
78,455,761 | https://en.wikipedia.org/wiki/Napropamide | Napropamide is an acetamide chemical herbicide. Its formula is . It is sold under the trade name of Devrinol, and was first manufactured in 1969.
Use
Napropamide is used as a herbicide by inhibiting the growth of roots. It is used against annual grasses and broadleaf weeds. The d-isomer is noted as being significantly more effective than the racemic mixture against certain weeds.
See also
HRAC classification
References
Acetamides
Herbicides
Diethylamino compounds
Naphthol ethers | Napropamide | [
"Biology"
] | 110 | [
"Herbicides",
"Biocides"
] |
78,455,976 | https://en.wikipedia.org/wiki/C23H20N6O | {{DISPLAYTITLE:C23H20N6O}}
The molecular formula C23H20N6O may refer to:
Mocetinostat
Zipalertinib | C23H20N6O | [
"Chemistry"
] | 41 | [
"Isomerism",
"Set index articles on molecular formulas"
] |
78,455,988 | https://en.wikipedia.org/wiki/C22H26N6O2 | {{DISPLAYTITLE:C22H26N6O2}}
The molecular formula C22H26N6O2 may refer to:
Saruparib
Verucerfont | C22H26N6O2 | [
"Chemistry"
] | 42 | [
"Isomerism",
"Set index articles on molecular formulas"
] |
78,456,163 | https://en.wikipedia.org/wiki/Loop%20extrusion | Loop extrusion is a major mechanism of Nuclear organization. It is a dynamic process in which structural maintenance of chromosomes (SMC) protein complexes progressively grow loops of DNA or chromatin. In this process, SMC complexes, such as condensin or cohesin, bind to DNA/chromatin, use ATP-driven motor activity to reel in DNA, and as a result, extrude the collected DNA as a loop.
Background
The organization of DNA presents a remarkable biological challenge: human DNA can reach 2 meters and is packed into the nucleus with the diameter of 5-20 µm. At the same time, the critical cell processes involve complex processes on highly compacted DNA, such as transcription, replication, recombination, DNA repair, and cell division.
Loop extrusion is a key mechanism that organizes DNA into loops, enabling its efficient compaction and functional organization. For instance, in vitro experiments show that cohesin can compact DNA by 80%, while condensin achieves a remarkable 10,000-fold compaction of mitotic chromosomes, as evidenced by microscopy, Hi-C, and polymer simulations.
Another challenge lies in establishing long-range genomic communication, which can span hundreds of thousands of base pairs. Physical encounters between genomic elements are intrinsically random and promiscuous without mechanisms to facilitate them. Loop extrusion has been proposed to provide an effective solution to regulate contacts by bringing target elements into proximity while limiting contact with unwanted loci.
Key components
The key components of the loop extrusion process are
DNA molecule that serves as the substrate for the movement of extruder
Extruders, usually SMC complexes, that moves along DNA in ATP-dependent manner
Accessory factors
Loaders of the extruder, a factor that facilitates loading of extruder on DNA (NIPBL/MAU2 usually play the key role in loading extruder on DNA)
Unloaders of the extruder, the molecule that facilitates detachment of extruder from DNA (for example, WAPL)
Road-blocks located on DNA that present a hindrance to extruder movement and lead to stalling of the extrusion machinery.
SMC proteins
Loop extrusion is performed by the SMC family of protein-complexes which includes cohesin, condensin, and SMC5/6 each playing specialized roles depending on the organism, cell cycle phase, and biological context. Cohesin mediates chromatin loop formation and stabilization, particularly during interphase in vertebrates, where it facilitates transcriptional regulation by promoting distal enhancer-promoter interactions. During mitosis and meiosis, cohesin dissociates from chromosome arms ceding its loop extrusion role to condensin. Loop extrusion by condensin mediates large-scale chromosome compaction, creating the compact, rod-like chromosome structures required for accurate segregation. Unlike cohesin and condensin, SMC5/6 is a loop extruding factor which primarily functions in maintaining genome integrity during DNA damage repair and resolving replication stress.
Despite their distinct roles, SMC complexes share a highly conserved ring-like structure. Two SMC proteins (usually, SMC1 and SMC3) are connected via a hinge region and linked at their heads by a kleisin subunit, forming a closed ring. These two SMC proteins have ATPase domains at their heads, which bind together and hydrolyze ATP. Cycles of ATP binding and hydrolysis mediate conformational changes in the ring structure, driving DNA translocation and stepwise loop extrusion. ATP is essential for both initiating loop extrusion (e.g., loading SMC complexes onto DNA) and propagating it (growing loops by translocating along DNA). The tension within the DNA significantly influences extrusion efficiency. At low tension, SMC complexes can make larger loop-capture steps, while higher tension can lead to stalling or reversal of loop extrusion.
Modifications and factors for loading/unloading
The dynamic nature of loop extrusion is tightly controlled by accessory factors and post-translational modifications, especially in the case of cohesin. In vertebrates, NIPBL (and orthologs like Mau2 in yeast or SCC2 and SCC4) is crucial for loading SMC complexes onto DNA, initiating and maintaining active extrusion. PDS5 is thought to pause the extrusion process. The SMC can then either restart extruding or be unloaded by the additional binding of WAPL, which ensure proper recycling and turnover. Post-translational modifications also play a key role. Acetylation of cohesin by enzymes such as ESCO1 and ESCO2 stabilizes chromatin loops, particularly at CTCF-bound sites. Similarly, SUMOylation, mediated by the NSE2 subunit of the SMC5/6 complex, enhances the recruitment of SMC5/6 to sites of DNA damage, supporting its role in genomic stability.
Roadblocks of loop extrusion
Loop extruders can encounter various obstacles while extruding. For example, many of which were shown to directly interact with cohesin and hypothesized to stop its movement on DNA. However, in vivo experiments demonstrate that cohesin can frequently bypass obstacles larger than its ring size.
Other cohesin and condensin molecules: Extruding cohesins and condensins has been found to be obstacle to other extruders that they encounter on the way. As such, they present a fundamental road-block that can be randomly encountered on the DNA.
CTCF: The C-terminal DNA-binding domain of CTCF has been shown to directly interact with SA2 and SCC1 subunits of cohesin to stop extrusion and retain it on DNA with recent evidence suggesting a tension-dependence to the interaction. CTCF stalls cohesin in a highly directional manner where cohesin can bypass CTCF in one orientation but stalls when encountering it in the opposite orientation. This directionality allows for the creation of isolated domains on the genome called Topologically Associating Domains (TADs) which have been proposed to have a large role in gene-regulation.
Polymerase: Transcribing polymerases can serve as barriers to cohesin that may not only stall extruders but also act as a motor pushing cohesin in the direction of polymerase movement. The size of a polymerase with an RNA transcript is usually larger than the size of the cohesin ring, and the stall force of cohesin is much smaller than that of polymerase, allowing for effective barrier function by polymerase. Furthermore, it has been found that RNA can directly interact with cohesin subunits.
Helicase: MCM helicase has been found to counteract the extrusion of cohesin on DNA.
R-loops: Some evidence suggests that R-loops can also act as barriers to loop extrusion, and R-loops have been shown to interact with cohesin subunits. However, other evidence suggests that R-loops may instead act as cohesin loaders.
Molecular mechanism
The molecular mechanisms of DNA-loop extrusion by SMC proteins have not yet been fully understood, but recent structural studies have made significant progress in developing several working models, like the scrunching model, the Brownian-ratchet model, the DNA-segment capture model/DNA-pumping model, the hold-and-feed model and the swing-and-clamp model.
Evidence for loop extrusion
Evidence for loop extruding molecules and their properties
The first direct evidence of loop extrusion came from in vitro imaging studies on fluorescently labeled DNA with condensin or cohesin. Extrusion was found to be ATP-dependent and happened at ~1-3kb/s. The stall force was measured to be around 0.1-1pN which is small compared to other molecular motors.
Evidence for the biological role of loop extrusion
Most work on the biological role of loop extrusion relies on inhibiting loop extruders and observing the consequences. Depletion of cohesin leads to the disappearance of TADs and some loss in transcription genome-wide. In more specific settings, inhibition of cohesin has been found to inhibit neuronal maturation and differentiation and function of dendritic cells. Depletion of either condensin I or condensin II at the entry into mitosis leads to abnormal chromosome formation and improper segregation of sister chromatids.
Biological function
Loop extrusion has been found across the tree of life with suggested roles in immune response, DNA repair, enhancer-promoter interactions, and mitosis.
Mitosis in eukaryotes: In mitosis, loop extrusion by condensin is critical for the segregation of sister chromatids and for providing structural rigidity after separation. Condensin I has been found to modulate the size and arrangement of nested inner loops and condensin II organizing the backbone from which loops emanate.
Cell division in bacteria: In bacteria, SMC proteins have been found to maintain the juxtaposition of the chromosome arms by loading at the centromere and extruding until the terminus.
Topologically associating domains (TADs): During interphase, chromosomes are locally compacted at the sub-megabase scale into so-called TADs. Generally, they are bordered by motifs for CTCF and completely disappear if either cohesin or CTCF is degraded.
V(D)J recombination: Loop extrusion by cohesin has been found to play a key role in V(D)J recombination to generate diversity in antibodies and T-cell receptors as depletion of cohesin inhibits V(D)J recombination. There are CTCF motifs throughout the recombination region, and inversions of their orientation or mutation of the motifs lead to changes in recombination probabilities consistent with those predicted by loop extrusion.
Protocadherin promoter choice: Protocadherins are mammalian proteins involved in cell adhesion of the neurons encoded in DNA in multiple similar genes located in the protocadherin locus. Neurons usually express only a subset of the protocadherins, enabling variability in the interactions between neurons. The choice of protocadherins rely on cohesin, which bridges alternative promoters of protocadherin with the enhancer in a CTCF-dependent manner. This process involves intricate regulation by CTCF and WAPL.
Theoretical models of loop extrusion
In mathematical models of loop extrusion, the two legs of a loop-extruding factor (LEF) are represented as points on a one-dimensional line, evolving according to different extrusion policies:
LEF Translocation: These dictate how LEFs move along the chromatin. These include symmetric extrusion—where both legs move in opposite directions—and one-sided extrusion—where one leg remains stalled while the other moves. Cohesin is often modeled with symmetric extrusion, while condensin is thought to follow a one-sided extrusion mechanism.
Stochastic Binding and Unbinding: LEFs bind to chromatin at a random time and position along the chain, and unbind after a characteristic time.
LEF-LEF interactions: When LEFs encounter one another, different interaction policies can be implemented. LEFs may halt upon collision, or bypass each other, as observed in some contexts.
Extrusion Barriers: Bound proteins such as CTCF or RNA polymerase II can act as obstacles, stalling or halting LEF motion.
Since the exact modalities of LEF dynamics remain uncertain, these models provide a flexible framework to explore different hypothetical behaviors of LEFs.
In these models, the statistics of LEFs are characterized by two key physical parameters:
Processivity (): Average size of a loop extruded by an unobstructed LEF before dissociating. This characteristic loop size depends on the extrusion speed and the residence time of the LEF on the chromatin.
Separation (): Average distance between LEFs on the chromatin fiber. It is determined by the total number of LEFs and the length of the chromatin . A shorter separation results in denser packing of loops, while larger separation leaves gaps between loops.
The interplay of these two parameters, encapsulated by the dimensionless parameter , defines two states of chromatin organization:
Sparse State (): LEFs operate independently, forming isolated loops with large gaps between them. This state results in minimal compaction of the chromatin fiber.
Dense State (): LEFs are abundant enough to form a continuous, gapless array of loops. This leads to significant chromatin compaction, as seen during mitosis.
References
Nuclear organization | Loop extrusion | [
"Biology"
] | 2,714 | [
"Nuclear organization",
"Cellular processes"
] |
78,459,275 | https://en.wikipedia.org/wiki/Plasticity%20%28software%29 | Plasticity is a 3D computer graphics software program that runs on Windows, MacOS, and Linux. It runs on Parasolid's geometric modeling kernel. It is pitched as CAD for artists.
Features
Non-uniform rational B-spline
Solid modeling
Polygon mesh modeling
Boolean operations
Real-time rendering
SpaceMouse support
Blender Bridge - Real-time sync between Plasticity and Blender
See also
List of 3D computer graphics software
List of 3D modeling software
References
External links
nkallen/plasticity
Computer-aided design
Splines (mathematics)
3D computer graphics
3d Modelling Software
3D graphics software
Software | Plasticity (software) | [
"Engineering"
] | 123 | [
"Computer-aided design",
"Design engineering"
] |
78,461,291 | https://en.wikipedia.org/wiki/Napactadine | Napactadine is an antidepressant which has structural properties that look similar to PAL-287 or methamnetamine, but is based on an amidine functional group.
Synthesis
The synthesis of napactadine has been described:
Reaction of N-methyl-2-(naphthalen-2-yl)acetamide [2086-65-9] (1) with triethyloxonium fluoroborate (Meerwein reagent) [368-39-8] (2) affords the corresponding imino ether (3). Exposure of this intermediate to methylamine (4) leads to napactidine (5).
References
2-Naphthyl compounds
Amidines | Napactadine | [
"Chemistry"
] | 155 | [
"Bases (chemistry)",
"Amidines",
"Functional groups"
] |
78,461,518 | https://en.wikipedia.org/wiki/Nitrafudam | Nitrafudam is an antidepressant compound that was developed in the 1970-1980s. It contains three functional groups: a nitrobenzene, a furan ring and an amidine.
Synthesis
Azo coupling between 2-nitrophenyldiazonium chloride [119-66-4] (1) and furfural (2) leads to 5-(2-nitrophenyl)furfural [20000-96-8] (3). Treatment of the aldehyde with hydroxylamine gives the corresponding aldoxime (PC789659). Upon dehydration, FGI to the nitrile occurs [57666-58-7] (4). A Pinner reaction with anhydrous methanolic hydrogen chloride gives the corresponding imidate (imino-ether) [62821-40-3] (5). An addition-elimination reaction with ammonia causes FGI to an amidine, thus completing the synthesis of nitrafudam (6).
References
Amidines
Nitrobenzenes
Furans
Antidepressants | Nitrafudam | [
"Chemistry"
] | 239 | [
"Bases (chemistry)",
"Amidines",
"Functional groups"
] |
78,462,319 | https://en.wikipedia.org/wiki/Melicopidine | Melicopidine is an alkaloid. Its formula is . It, along with melicopine and melicopicine, is named for the Australian rutaceae (Melicope fareana) from which it was first isolated.
Occurrence
As an alkaloid, melicopidine naturally occurs in and has been isolated from Medicosma fareana and Sarcomelicope megistophylla in addition to Melicope fareana.
References
Acridines
Alkaloids
Benzodioxoles
Methoxy compounds
4-Pyridones | Melicopidine | [
"Chemistry"
] | 115 | [
"Organic compounds",
"Biomolecules by chemical classification",
"Natural products",
"Alkaloids"
] |
78,462,514 | https://en.wikipedia.org/wiki/Benzoylferrocene | Benzoylferrocene (also known as ferrocenyl phenyl ketone) is a chemical. Its formula is . Little experimental data is available for this compound. It was first produced in 1961 by Karl Schlögl et al., along with several other ferrocene derivatives.
References
Ferrocenes | Benzoylferrocene | [
"Chemistry"
] | 69 | [
"Inorganic compounds",
"Inorganic compound stubs"
] |
78,464,236 | https://en.wikipedia.org/wiki/2024%20Palmyra%20airstrike | On 20 November 2024, the Israeli Air Force conducted an airstrike on residential buildings and an industrial area in Palmyra in central Syria. According to the Syrian Observatory for Human Rights, the strikes killed at least 108 people, including 73 Iranian-backed Syrian militiamen and 29 foreign Iranian-backed militiamen, mostly members of the Harakat Hezbollah al-Nujaba of Iraq, as well as 15 Hezbollah militants. The strikes also injured more than 50 people.
Background
Since the beginning of the Syrian civil war in 2011, Israel has been conducting hundreds of airstrikes in Syria, targeting the Syrian Army and Iran-backed groups in the country. Since the Israel–Hamas war started on 7 October 2023, Israel increased its airstrikes on Syria as its hostilities with Hezbollah intensified.
Airstrikes
The Syrian Ministry of Defense reported that the airstrikes, which took place at 1:30 p.m. on 20 November. 2024, were launched from the direction of the United States military base in Al-Tanf and caused "significant material damage". The Syrian Observatory for Human Rights also reported that the strikes targeted "a weapons depot near the industrial area" in Palmyra. The United Nations deputy special envoy to Syria told the UN Security Council that the attack was "likely the deadliest Israeli strike in Syria to date".
Syrian state media initially reported that the attacks killed 36 people and wounded at least 50 more, as a result of the strikes on residential buildings and an industrial area in Palmyra. The United Kingdom-based Syrian Observatory for Human Rights however reported that the airstrikes killed more than 108 people. The dead include 73 Iranian-backed Syrian militiamen, including 11 officers working for Hezbollah in Lebanon, and 29 Iranian-backed non-Syrian militiamen, primarily Iraqi fighters of Harakat Hezbollah al-Nujaba. The Israel Defense Forces declined to comment on the airstrike.
References
2024 airstrikes
November 2024 events in Syria
Middle Eastern crisis (2023–present)
Iran–Israel conflict during the Syrian civil war
Israeli airstrikes during the Syrian civil war
Palmyra in the Syrian civil war
2024 building bombings
Residential building bombings in Syria
Military operations of the Syrian civil war in 2024
Military operations of the Syrian civil war involving Hezbollah
Military operations of the Syrian civil war involving the Syrian government
Industrial fires and explosions
2024 industrial disasters
2024 Iran–Israel conflict | 2024 Palmyra airstrike | [
"Chemistry"
] | 487 | [
"Industrial fires and explosions",
"Explosions"
] |
78,470,042 | https://en.wikipedia.org/wiki/Joint%20Universities%20Accelerator%20School | The Joint Universities Accelerator School (JUAS) is an educational program that specializes in the field of particle accelerator science and technology. Established in 1994, JUAS is a collaborative initiative involving multiple universities, research centers, and institutions. It provides advanced training in accelerator physics and engineering for graduate students and professionals. The program is hosted annually, in Archamps, near Geneva, Switzerland, under the auspices of the European Scientific Institute (ESI). Its location near the European Organization for Nuclear Research (CERN) and other major research facilities offers participants unique access to cutting-edge expertise and resources.
JUAS originated in 1990 through a collaboration between CERN physicists, the European Synchrotron Radiation Facility (ESRF), and the Université Joseph Fourier in Grenoble, France, with support from Haute-Savoie local authorities. Since its inception, the school has trained more than 1,400 participants, creating a skilled workforce for addressing challenges in accelerator physics and technology. Alumni frequently secure positions at leading laboratories, including CERN, DESY, and Fermilab, or apply their skills in sectors such as medicine and energy. By 2024, the school had partnered with 14 universities across Europe.
JUAS caters primarily to graduate students with a scientific background who are new to accelerator physics. The program offers two complementary five-week courses:
Course 1: Focuses on the theoretical foundations of particle accelerator science.
Course 2: Covers the technology and applications of particle accelerators.
Participants may enroll in one or both courses, which feature interactive teaching by experts from leading institutions and hands-on learning opportunities.
Since August 2021, JUAS has been directed by Elias Métral (CERN).
Many of the JUAS lecturers do also lecture at the CERN Accelerator School.
List of former JUAS Directors
References
External links
Official website
Physics education
Education in France
CERN | Joint Universities Accelerator School | [
"Physics"
] | 377 | [
"Applied and interdisciplinary physics",
"Physics education"
] |
78,470,155 | https://en.wikipedia.org/wiki/Cyber%20Security%20Management%20System | A Cyber Security Management System is a form of Information security management system, particularly focussed on protecting automation and transport systems. The EU Cybersecurity Act, of 2019, led to the creation of UNECE working groups which developed the Cyber Security Management Systems (CSMS) concept (and also an approach for securing over-the-air updates of vehicle systems), which were formalised in UN Regulation 155.
Context
Security technologies, and threats, can evolve much more quickly than regulatory bodies; so the CSMS emphasises a system of technologies and processes which can adapt more quickly, without relying on a narrowly-defined list of technical controls in a standard. Consequently, the CSMS is intended to be technology-neutral, much like ISO 27001, unlike detailed technical security standards such as PCI DSS.
Framework
See also
IEC 62443
ISO/SAE 21434
ISO/IEC 27001
Cyber Essentials
References
Further reading
Draft Recommendation on Cyber Security of the Task Force on Cyber Security and Over-the-air issues of UNECE WP.29 GRVA
Information assurance standards
Information governance | Cyber Security Management System | [
"Technology"
] | 222 | [
"Computer standards",
"Information assurance standards"
] |
72,686,056 | https://en.wikipedia.org/wiki/Hyalochlorella | Hyalochlorella marina, the only species in the genus Hyalochlorella and also known as Dermocystidium sp., is a marine heterotrophic eukaryote with uncertain phylogenic position.
Phylogeny
Hyalochlorella marina was first classified as a fungus under the name Dermocystidium sp. Based morphology and development, it has been classified as a Chlorophyta related to Chlorella but different from the parasite microalgae Prototheca. It also shows similarities to more recently described Ichthyosporea Sphaeroforma species, in particular Sphaeroforma tapetis (previously known as Pseudoperkinsus tapetis).
Ecology
It is an epiphyte of marine seaweeds but has also been isolated from seawater. Hyalochlorella is found on several shores of east and west coast of the United States, Canada, the United Kingdom, and off the Faroe Islands.
References
Taxa described in 1970
Controversial taxa
Oocystaceae
Chlorophyta genera
Monotypic algae genera | Hyalochlorella | [
"Biology"
] | 227 | [
"Biological hypotheses",
"Eukaryotes",
"Eukaryote stubs",
"Controversial taxa"
] |
72,688,065 | https://en.wikipedia.org/wiki/Sanjay%20Mathur | Sanjay Mathur (born 1968) is an inorganic chemist, current president (Oct. 2022 - Oct. 2023) of the American Ceramic Society. acting director of the Institute of Inorganic Chemistry at the University of Cologne, honorary co-director of the Institute of Renewable Energy Sources at the Xi'an Jiaotong University, a World Class University Professor at the Chonbuk University. He is an adjunct professor at the Indian Institutes of Technology in Chennai and has held visiting professorships at the Central South University, the Tokyo University of Agriculture and Technology, the National Institute of Science Education and Research. He was awarded the Honorary Doctorate of the Vilnius University in 2016. He is an elected fellow of the American Ceramic Society, the American Society for Metals, the European Science Academy, the Indian National Science Academy and has been awarded with the fellowships of the Alexander von Humboldt Foundation. Mathur is known for his library of single source precursors for the production of nanostructured ceramic materials with tailormade properties, attaining a h-index of 70 and over 18000 citations.
Biography
In 1994 he moved to Germany, joined the Saarland University as an Alexander von Humboldt Fellow (1994-1996). Following this, he worked for his habilitation (2004) at the Saarland University until he accepted an offer of the Würzburg University in 2006 to become a Professor of Inorganic Chemistry. At the Würzburg University he established a research programm on the synthesis of nanomaterials and thin film systems by means of chemical vapour deposition using chemically tailored organometallic precursors. In 2008, he was offered a full professorship in Inorganic and Materials Chemistry at the University of Cologne which he accepted. He established the Steinbeis technology-transfer center Materials Alliance Cologne, which supports small- and medium-sized enterprises to innovate their technology portfolio.
Mathur serves as Board member for the German Ceramic Society and the federation of chemical industries ChemCologne in Rhineland. Mathur has mentored a number of doctoral and postdoctoral researchers from a large number of nations. He has also served as the “International Ambassador” of the University of Cologne to foster international collaboration. He has received calls as the director of the Institute for Functional Materials in KTH Royal Institute of Technology (2013) and director of Institute for Technologies of Ceramic Components and Composites at the Stuttgart University (2020).
Research
Mathur's research focuses on chemical concepts for the synthesis and processing of nanostructured ceramics and composites through the transformation of specially developed chemical feedstocks for energy and health applications. His research group has developed approaches for processing metal oxide nanoparticles, nanowires and nanostructured coatings, applicable in the fields of biomedicine (e.g. drug delivery and implant integration), sensing (gas and moisture detection), protective coatings (including barrier and anti-corrosion solutions) and functional surface modifications (e.g. transparent conductive oxides, photocatalytic materials and hydrophobic/hydrophilic coatings).
Mathur has also played a role in coordinating joint research projects with European consortia and industrial partners. He has been involved in technology transfer and collaboration with industry, particularly in the areas of sensors, electrodes, filters, catalytic supports and battery applications.
Academic
Mathur has published more than 500 articles including 15 reviews and book chapters. He has been invited to speak at over 200 international conferences, has given over 250 seminars in 35 countries and has chaired/co-chaired several international conferences and symposia. He has edited 11 book in the field of nanomaterials science and engineering and is the co-owner of 11 patents originated in joint research projects and industrial collaboration. Mathur has led joint research projects with industry and has been involved with technology transfer and industrial collaborations. He serves as the Faculty Advisor for the International Chapters of the Materials Research Society, jointly recognized by the European Materials Research Society (E-MRS) as well as the American Ceramic Society International Germany Chapter established at the University of Cologne.
Awards and recognition
2010: Global Star Award of the ECD of American Ceramic Society
2012: Academician, World Academy of Ceramics, Italy
2012: International Ambassador, University of Cologne
2014: World Class University Distinguished Professor, Chonbuk University, Korea
2014: Fellow, the American Ceramic Society
2015: Bridge-Building Award, American Ceramic Society
2016: Lee Hsun Award, Institute of Materials Res – Chinese Academy of Science, China
2016: Honorary Doctorate (h.c.), Vilnius University, Lithuania
2017: Fellow, the ASM International, USA
2019: Awarded, President’s Appreciation Award, KITECH, Korea
2019: Lifetime Achievement Award, Indian Science Congress Association, Kolkata, India
2020: Fellow of the European Academy of Science
2020: Elected to serve on the DFG Expert Panel (Fachkollegiat) for Functional Materials
2020: Appointed as Board Member of the German Ceramic Society
2021: Elected as Fellow of the Indian National Science Academy
2021: Elected Member of European Academy of Science, Brussels
2021: Appointed to European Materials Research Council, Strasbourg
2021: Elected Member, International Union of Materials Research Societies
2021: Woody White Award, Materials Research Society, USA
2022: International Frontiers Award of International Union of Materials Research Societies
2022: Orton Jr. Lectureship Award of the American Ceramic Society, USA
2022: Elected Secretary of the International Unions of MRS (IU-MRS)
2022: President, American Ceramic Society (2022-23)
2023: Medal for Excellence in Chemical Research, Chemical Research Society India
References
1968 births
Living people
Inorganic chemists
People from Ujjain
Academic staff of the University of Cologne
Vikram University alumni | Sanjay Mathur | [
"Chemistry"
] | 1,152 | [
"Inorganic chemists"
] |
72,688,939 | https://en.wikipedia.org/wiki/List%20of%20Saxifragales%2C%20Vitales%20and%20Zygophyllales%20families | Saxifragales, Vitales and Zygophyllales are three orders of flowering plants with a total of 18 families. They belong to the superrosids, a group of around 150 related families, including the rose family. They are the only such orders that are not included in three large subgroups of the superrosids: the COM clade, the nitrogen-fixing clade and the malvids.
The order Saxifragales includes fruit-bearing shrubs, woody vines, succulents, aquatics, and many ornamental trees and garden plants, including stonecrops, currants and witch-hazels. Peonies are bred by horticulturists and widely cultivated in temperate gardens. The antiseptic resin of sweetgum trees has been used as a balm since biblical times. Cercidiphyllum japonicum, the largest tree species native to Japan, is used to make boards for the game of Go. Redcurrants, rich in pectin, are used in jams and juices.
Vitales and Zygophyllales include trees, shrubs, vines and herbaceous plants. Krameria triandra is used as an astringent in mouthwash and toothpaste. Wine, juices and jellies are made from grapes, and the leaves are also edible. Guaiacum, in the twinleaf family, yields exceptionally hard lumber.
Glossary
From the glossary of botanical terms:
annual: a plant species that completes its life cycle within a single year or growing season
basal: attached close to the base (of a plant or an evolutionary tree diagram)
deciduous: shedding or falling seasonally, as with bark, leaves, or petals
herbaceous: not woody; usually green and soft in texture
perennial: not an annual or biennial
succulent (adjective): juicy or fleshy
unisexual: of one sex; bearing only male or only female reproductive organs
woody: hard and lignified; not herbaceous
The APG IV system is the fourth in a series of plant taxonomies from the Angiosperm Phylogeny Group.
Saxifragales is the only superrosid order that is not also a member of the rosids. Although the Saxifragales families are quite diverse, there are a few visible traits that can be linked to many of them. The plants have relatively small seeds, except in the family Peridiscaceae. Flowers tend to have separate, unfused petals, without nectar-secreting glands. The pollen-bearing anthers are often attached by their bases. Most fruits are follicles (seed pods). There are often two distinct ovaries, each with a hypanthium, a tube or cup-like structure in a flower that includes the bases of the sepals, petals, and stamens.
Vitales and Zygophyllales
Saxifragales
See also
List of plant family names with etymologies
Notes
Citations
References
See the licence.
See their terms-of-use license.
Systematic
Saxifragales, Vitales and Zygophyllales families
Saxifragales, Vitales and Zygophyllales families
Saxifragales, Vitales and Zygophyllales families | List of Saxifragales, Vitales and Zygophyllales families | [
"Biology"
] | 675 | [
"Lists of biota",
"Lists of plants",
"Plants"
] |
72,689,371 | https://en.wikipedia.org/wiki/Stypellopsis | Stypellopsis is a genus of fungi in the order Auriculariales. Basidiocarps (fruit bodies) are effused, gelatinous, crystalline or net-like and occur on fallen conifer wood. Species were formerly placed in Stypella or Protomerulius, but molecular research, based on cladistic analysis of DNA sequences, distinguishes Stypellopsis from these genera and from the morphologically similar genus Mycostilla. The type species occurs in northern Europe, Stypellopsis farlowii in North America.
References
Auriculariales
Basidiomycota genera
Taxa described in 2018 | Stypellopsis | [
"Biology"
] | 133 | [
"Fungus stubs",
"Fungi"
] |
72,691,000 | https://en.wikipedia.org/wiki/Miss%20Katie%20%282022%20ship%29 | Miss Katie is a hopper dredge owned by EJE Dredging Service, LLC. Her primary mission is to maintain the channels through Oregon Inlet and nearby Hatteras Inlet in the Outer Banks of North Carolina. Keeping these navigable waterways open is important to local fishing, recreational boating, and other maritime interests.
Construction and characteristics
Silt from several large rivers and the movement of beach sand along the Outer Banks has historically threatened navigable channels through the barrier islands. This has negatively impacted the local fishing industry and other maritime businesses. In addition, shoaling at the mouths of the inlets, or "bars", has been a factor in the loss of ships and lives.
In 1950, Congress authorized the U.S. Army Corps of Engineers to maintain a dredged channel deep through Oregon Inlet. High winds, strong tides, and major storms have largely thwarted this effort. Despite spending well over $100 million on dredging, the majority of the time the channel has fallen below its authorized depth, and sometimes it has been closed completely. For example, a storm during the week of May 8, 2022 moved enough sand to reduce the channel through Oregon Inlet to less than deep, effectively closing it to most vessels.
Local efforts to keep the inlets open resulted in a partnership between the State of North Carolina, Dare County, and EJE Dredging Service to build and operate Miss Katie. On May 20, 2019, the Dare County Board of Commissioners approved the contract for the construction of the vessel. She was designed by Jensen Naval Architects & Marine Engineers, a unit of Crowley Maritime. She was built at the Morgan City, Louisiana facility of Conrad Shipyard, LLC. The ship was launched on April 4, 2022.
Miss Katie departed the Conrad Shipyard on August 13, 2022 and arrived at her new homeport, Wanchese, North Carolina six days later. She was christened on October 13, 2022 at a ceremony at Wanchese. She was christened by Brooke Burr, wife of U.S. Senator Richard Burr.
Miss Katie is long and has a beam of . Her hull is constructed of welded steel plates. Her draft is , when her hopper is loaded with dredging spoil. She displaces 566 tons light loaded, but with a full load of spoil her displacement is over 1000 tons. Her hopper can hold up to 512 cubic yards of dredging spoil.
Miss Katie is a "suction dredge". She pulls two suctionheads, referred to as "dragheads", along the seafloor as she moves slowly through the water. The dragheads are connected to pipes called "drag arms" that descend from both sides of the ship. Sand, mud, and silt on the seafloor enters the dragheads and is pulled up through the drag arms by powerful pumps. It is then deposited in a hopper in the middle of the ship. During dredging operations, she can fill her hopper in 30 minutes. When the hopper is full, the ship sails to an offshore location and opens doors in the bottom of the hopper, allowing the dredge spoil to fall to the sea bottom. Alternatively, she can pump sand overboard for beach nourishment or other purposes.
The ship is propelled by two Cummins Diesel engines, each rated at 760 horsepower that drive two ZF ATZ 4111 azimuth thrusters. She has two Cummins QSM-11 Diesel generators which produce 250 Kw each and a Cummins QSB-7 emergency generator which produces 99 Kw. She has two bow thrusters to improve maneuverability.
The ship is crewed by 5 civilian mariners.
The ship's namesake is Caitlyn "Katie" Whitehurst, daughter of Judson Whitehurst, a partner in EJE Dredging Service, the vessel's owner.
Funding and management
The construction of Miss Katie was funded by a three-way public-private partnership between the State of North Carolina, Dare County, and EJE Dredging Service. In its 2018 budget, North Carolina allocated $15 million to Dare County from its Shallow Draft Navigation Channel Dredging and Aquatic Weed Fund. The money provided a forgivable loan to a private dredge operator willing to build a dredge to keep the Inlets open. The state directed that the loan could be forgiven at the rate which dredging services were provided below the cost that would have been charged by the Army Corps of Engineers for the same work. The loan was to have a term of ten years, renewable for another five with the agreement of both parties. In the event that the loan was not fully forgiven by the end of the contract term, the dredge operator would repay any outstanding balance. The state designated the Oregon Inlet Task Force, a group created by Dare County in 2013 to manage dredging in the inlets, as the principal interface between the government and the dredge operator. The state gave the Oregon Inlet Task Force the option to allow the dredge to take on other projects if it felt that the ship could do so without jeopardizing the goal of keeping the inlets open.
The state further specified that the private dredge operator would be selected through a proposal process organized by the Oregon Inlet Task Force. Two proposals were received. One was from Cashman Dredging, a Massachusetts-based, large, experienced dredging company with operations along the Atlantic and Gulf Coasts of North America. The other was from EJE Dredging Service, a North Carolina firm with little experience dredging and no current dredging operations. It was reported that EJE was selected over its more experienced competitor because it promised to base its dredging business in the Outer Banks.
Dare County budgeted $3 million in 2023 for dredging in Oregon Inlet, which will be matched with $9 million from the State of North Carolina. A further $250,000 of dredging is planned for Hatteras Inlet, with $750,000 contributed by the State.
Operating history
The U.S. Coast Guard issued Miss Katie her certificate of inspection, allowing the vessel to begin operations, on July 29, 2022.
Miss Katie's first assignment was to help reopen a channel through Oregon Inlet that had been closed by storms. She and the Army Corps of Engineers dredges USAV Snell and USAV Merritt, dredged an entirely new channel from August 2022 to January 2023.
Miss Katie dredged Hatteras Inlet for the first time between January 27 and February 5, 2023. She removed 14,172 cubic yards of sand from the channel at a cost of approximately $220,000.
References
Dredges
Dare County, North Carolina
Outer Banks | Miss Katie (2022 ship) | [
"Engineering"
] | 1,349 | [
"Dredges",
"Mining equipment"
] |
72,691,605 | https://en.wikipedia.org/wiki/HD%2031134 | HD 31134, also designated as HR 1561, is a solitary star located in the northern circumpolar constellation Camelopardalis, the giraffe. It is faintly visible to the naked eye as a white-hued star with an apparent magnitude of 5.74. Gaia DR3 parallax measurements place it 473 light years away. It appears to be approaching the Solar System with a heliocentric radial velocity of . At its current distance, HD 31134's brightness is diminished by 0.35 magnitudes due to interstellar dust. It has an absolute magnitude of +0.19.
The object has a stellar classification of A2 Vs, indicating that it is an A-type main-sequence star with sharp or narrow absorption lines due to slow rotation. Two sources remove the s prefix and instead list it as an ordinary dwarf star while one lists it as a more evolved giant star. Abt and Morell (1995) list it as a slightly hotter peculiar Ap star, but it is now considered unlikely to be chemically peculiar. It has 2.74 times the mass of the Sun and an enlarged radius of . It radiates 103 times the luminosity of the Sun from its photosphere at an effective temperature of . HD 31134 is a rather evolved star, having completed 97.6% of its main sequence lifetime at the age of 432 million years. Consistent with its spectrum, it spins modestly with a projected rotational velocity of .
References
A-type main-sequence stars
Camelopardalis
BD+52 00898
031134
1561
022936 | HD 31134 | [
"Astronomy"
] | 332 | [
"Camelopardalis",
"Constellations"
] |
72,693,375 | https://en.wikipedia.org/wiki/GJ%201002%20b | GJ 1002 b (also designated as Gliese 1002 b) is a potentially habitable exoplanet located 16 light-years away, in the constellation of Cetus. The planet, which has an Earth Similarity Index of 86%, is in the habitable zone of its parent star. GJ 1002 b has a minimum mass of 1.08 Earth masses and is estimated by the Planetary Habitability Laboratory to have 1.03 times the radius of Earth and a surface temperature of 261 Kelvin.
Detection
GJ 1002 b was detected in 2022 via the radial velocity method, which was used to measure the planet's minimum mass.
Host star
The host star, GJ 1002, is a quiet M5.5V type red dwarf not believed to release flares that could harm the atmosphere. The planet orbits its host star at a distance of 0.0457 AU (Astronomical units), with a 10.3 day orbital period and a 0.0 eccentricity.
See also
Proxima Centauri b, a potentially habitable planet of similar physical characteristics that is also orbiting a small red dwarf star.
References
Cetus
Exoplanets discovered in 2022
Exoplanets detected by radial velocity | GJ 1002 b | [
"Astronomy"
] | 254 | [
"Cetus",
"Constellations"
] |
72,693,689 | https://en.wikipedia.org/wiki/Association%20193 | Association 193 is an anti-nuclear non-governmental organisation in French Polynesia. The association is named for the 193 nuclear weapons tests conducted by France at Moruroa and Fangataufa between 1966 and 1996. It was established in 2014 to preserve the historical memory of nuclear testing and campaign for the French government to tell the truth about its impacts and compensate victims.
The association initially called for 2 July - the date of the first French nuclear test in Polynesia - to be made a formal date of commemoration. In January 2016 it launched its first major campaign, a petition for a referendum on the nuclear issue and on compensation. By February 2016 the petition had more than 30,000 signatures. It also worked with Mururoa e Tatou to organise a series of demonstrations around the visit of French President François Hollande. In July 2016 it organised an exhibition and public demonstration to mark the 50th anniversary of the first nuclear test. In October 2016 it successfully opposed plans for potentially contaminated gravel from Hao atoll to be used in road construction on Rikitea. In January 2017 it created a unit to assist test victims to claim compensation from the French government.
In August 2017 the association celebrated its third anniversary and announced its support for a campaign by the Maohi Protestant Church to pursue France for crimes against humanity in the International Criminal Court.
In March 2020 the association denounced changes to France's nuclear compensation law which would make it more difficult for victims to obtain compensation. It also denounced an attempt to further limit compensation via a clause slipped in to COVID-19 legislation.
References
Political organizations based in French Polynesia
2014 establishments in French Polynesia
Anti-nuclear organizations
Indigenous rights organizations | Association 193 | [
"Engineering"
] | 336 | [
"Nuclear organizations",
"Anti-nuclear organizations"
] |
72,695,585 | https://en.wikipedia.org/wiki/Succinprotocetraric%20acid | Succinprotocetraric acid is an organic chemical compound with the formula C22H18O12. It is the ester of succinic acid and protocetraric acid and it is classified as a depsidone.
Succinprotocetraric acid is produced by certain lichens.
Known sources
Buellia capensis
Chondropsis semiviridis
Menegazzia petraea
Parmelia reptans
Cladonia metacorallifera
Cladonia rangiferina
Cladonia arbuscula
Cetraria islandica, though only of a specific chemotype
References
Carbonyl compounds
Heterocyclic compounds with 3 rings
Dicarboxylic acids
Carboxylate esters
Lactones
Lichen products | Succinprotocetraric acid | [
"Chemistry"
] | 158 | [
"Natural products",
"Lichen products"
] |
72,695,599 | https://en.wikipedia.org/wiki/Danica%20Galoni%C4%87%20Fujimori | Danica Galonić Fujimori () is a Serbian-American chemical biologist who is a professor at the University of California, San Francisco. Her research considers nucleic acid synthesis and tissue engineering. In the search for new therapeutics and vaccines, she has studied the interactions between ribosomes and SARS-CoV-2.
Early life and education
Galonić Fujimori earned her undergraduate degree at the University of Belgrade. She moved to the University of Illinois Urbana-Champaign for her doctoral research, where she earned a PhD in biochemistry. Her research considered the development of two strategies for site-selective peptide modification. She then moved to the Harvard Medical School where she worked alongside Christopher T. Walsh.
Research and career
Galonić Fujimori has studied various biological processes, including chromatin formation, transcriptional regulation and DNA repair. Methylation impacts the regulation of biological processes, and the deregulation of methylation is associated with various diseases. As such, understanding and exploiting enzymatic regulation of methylation could provide an opportunity for therapeutic intervention. She has studied Jumonji domain-containing histone-lysine demethylases, complex proteins which catalyze the removal of methylation marks on the lysine residues of multiple histones can contain chromatin reader domains. These reader domains interact with chromatin, an interaction which is modulated by chromatin modifications. To probe the cellular function of the Jumonji family, the Galonić Fujimori laboratory develop small molecule inhibitors. She proposes that these molecules can be used to inhibit the aberrant demethylation that occurs in certain diseases. She has investigated the methylation of RNA, and how this impacts the cellular function of RNA.
Fujimori investigates how bacteria acquire immune responses to antibiotics. She has focused her efforts on antibiotics that target the ribosome of bacteria, which is involved with protein synthesis. Antibiotics such as linezolid bind to sites such as the peptidyl transferase center, blocking protein biosynthesis.
During the COVID-19 pandemic, Galonić Fujimori started working on virus-host interactions in response to SARS-CoV-2. She showed that bromodomain and extraterminal (BET) proteins were involved in the body's response to COVID-19 infection. She started working on pharmaceuticals to tackle future pandemics.
Awards and honors
2011 National Science Foundation CAREER Award
2015 University of California, San Francisco Haile T. Debas Academy of Medical Educators Excellence in Teaching Award
2015 University of California, Berkeley Sackler Sabbatical Exchange Program
2017 University of California, San Francisco Byers Award Lecture in Basic Sciences
2020 Keck Foundation WM Keck Medical Research Award
2020 Bowes Biomedical Investigator Award
Selected publications
References
Year of birth missing (living people)
Place of birth missing (living people)
University of California, San Francisco faculty
Harvard Medical School people
University of Belgrade alumni
University of Illinois Urbana-Champaign alumni
21st-century American biochemists
Serbian emigrants to the United States
Women biochemists
21st-century American women scientists
Living people | Danica Galonić Fujimori | [
"Chemistry"
] | 627 | [
"Biochemists",
"Women biochemists"
] |
72,696,339 | https://en.wikipedia.org/wiki/Porfiromycin | Porfiromycin is an N-methyl derivative of the antineoplastic antibiotic, mitomycin C, which is isolated from various Streptomyces bacterial species. As an antineoplastic agent, it is under investigation for the treatment of cancer, particularly head and neck cancer.
Porfiromycin works by generating oxygen radicals and alkylating DNA, resulting in interstrand cross-links and single-strand breaks. This inhibits DNA synthesis and leads to the death of cancer cells. It has a higher toxicity towards hypoxic cells, making it an attractive option for cancer treatment.
Porfiromycin can increase the risk of methemoglobinemia when taken with certain medications. It belongs to the class of compounds known as mitomycins, which are characterized by their aziridine ring linked to a 7-amino-6-methyl-cyclohexa[b]pyrrolizine-5,8-dione structure.
References
Antibiotics
Aziridines
Antineoplastic drugs
Heterocyclic compounds with 4 rings
Indolequinones
Quinones
Indoles
Carbamates
Amines | Porfiromycin | [
"Chemistry",
"Biology"
] | 241 | [
"Biotechnology products",
"Functional groups",
"Antibiotics",
"Amines",
"Biocides",
"Bases (chemistry)"
] |
72,696,572 | https://en.wikipedia.org/wiki/William%20J.%20van%20Ooij | William J. van Ooij is a retired University of Cincinnati professor known for elucidating the mechanisms of brass-rubber adhesion in tires, and as the founder of corrosion resistant coatings company Ecosil Technologies
Education
van Ooij completed his graduate education at Delft University of Technology in The Netherlands, earning his MS in chemical engineering in 1964 and his PhD in physical chemistry in 1971. He held a two-year post-doctoral position at Ames Laboratory at Iowa State University.
Career
He returned to The Netherlands to work as a senior research chemist for Akzo Research Laboratories (now Akzo Nobel). \ After 12 years in this role, van Ooij returned to the United States first as a visiting professor in the Department of Materials Engineering at Virginia Polytechnic Institute & State University, and later at the Colorado School of Mines as a professor of chemistry. He then was employed for 4 years at Armco Research & Technologies (now AK Steel) as head of the Corrosion Group. He joined the Department of Materials Science and Engineering faculty in University of Cincinnati's College of Engineering in 1993. During his career, he published approximately 350 scientific and technical publications, and he obtained 30 U.S. and 38 European patents.
in 1987, van Ooij was a founding editor of the scientific journal Journal of Adhesion Science and Technology.
He was the Chief Technology Officer for Ecosil Technologies, a startup founded with Max Sorenson and David Fairbourn that has become a leader in the application of silane surface treatments for corrosion protection of metals. His inventions enabled the replacement of chromate and phosphate systems in metallic surface treatment lines, and were recognized by the US EPA for their significant impact on eliminating toxic and cancer-causing processes.
Awards
2009 - Established Entrepreneur award from University of Cincinnati
2010 - Melvin Mooney Distinguished Technology Award from Rubber Division of the ACS
2010 - Ohio Patent Award from the Ohio Academy of Science
References
Polymer scientists and engineers
Living people
Year of birth missing (living people)
Tire industry people | William J. van Ooij | [
"Chemistry",
"Materials_science"
] | 405 | [
"Polymer scientists and engineers",
"Physical chemists",
"Polymer chemistry"
] |
68,322,822 | https://en.wikipedia.org/wiki/HD%2028700 | HD 28700 (HR 1433) is a solitary star in the southern constellation Caelum. It has an apparent magnitude of 6.12, making it visible to the naked eye under ideal conditions. Parallax measurements place the object at a distance of 384 light years and is currently receding with a heliocentric radial velocity of .
HD 28700 has a stellar classification of K1 III, indicating that it is a red giant. It has three times the Sun's mass and has expanded to ten times its radius. It radiates at 56 times the Sun's luminosity from its swollen photosphere at an effective temperature of , giving it an orange hue. HD 28700 has a projected rotational velocity too low to be measured accurately due to it being less than . HD 28700 has 120% the abundance of iron relative to the Sun. At a modeled age of 377 million years, HD 28700 is on the red giant branch fusing hydrogen in a shell around an inert helium core.
References
Caeli, 5
028700
020934
1433
Durchmusterung objects
K-type giants
Caelum | HD 28700 | [
"Astronomy"
] | 238 | [
"Caelum",
"Constellations"
] |
68,323,528 | https://en.wikipedia.org/wiki/Monoecy | Monoecy (; adj. monoecious ) is a sexual system in seed plants where separate male and female cones or flowers are present on the same plant. It is a monomorphic sexual system comparable with gynomonoecy, andromonoecy and trimonoecy, and contrasted with dioecy where individual plants produce cones or flowers of only one sex and with bisexual or hermaphroditic plants in which male and female gametes are produced in the same flower.
Monoecy often co-occurs with anemophily, because it prevents self-pollination of individual flowers and reduces the probability of self-pollination between male and female flowers on the same plant.
Monoecy in angiosperms has been of interest for evolutionary biologists since Charles Darwin.
Terminology
Monoecious comes from the Greek words for one house.
History
The term monoecy was first introduced in 1735 by Carl Linnaeus. Darwin noted that the flowers of monoecious species sometimes showed traces of the opposite sex function, suggesting that they evolved via hermaphroditism. Monoecious hemp was first reported in 1929.
Occurrence
Monoecy is most common in temperate climates and is often associated with inefficient pollinators or wind-pollinated plants. It may be beneficial to reducing pollen-stigma interference, thus increasing seed production.
Around 10% of all seed plant species are monoecious. It is present in 7% of angiosperms. Most Cucurbitaceae are monoecious including most watermelon cultivars. It is prevalent in Euphorbiaceae. Dioecy is replaced by monoecy in polyploid populations of Mercurialis annua.
Maize
Maize is monoecious since both pistillate (female) and stamenate (male) flowers occur on the same plant. The pistillate flowers are present on the ears of corn and the stamenate flowers are in the tassel at the top of the stalk. In the ovules of the pistillate flowers, diploid cells called megaspore mother cells undergo meiosis to produce haploid megaspores. In the anthers of the stamenate flowers, diploid pollen mother cells undergo meiosis to produce pollen grains. Meiosis in maize requires gene product RAD51, a protein employed in recombinational repair of DNA double-strand breaks.
Evolution
The evolution of monoecy has received little attention.
Male and female flowers evolve from hermaphroditic flowers via andromonoecy or gynomonoecy.
In amaranths monoecy may have evolved from hermaphroditism through various processes caused by male sterility genes and female fertility genes.
Monoecy may be an intermediate state between hermaphroditism and dioecy. Evolution from dioecy to monoecy probably involves disruptive selection on floral sex ratios. Monoecy is also considered to be a step in the evolutionary pathway from hermaphroditism towards dioecy. Some authors even argue monoecy and dioecy are related. But, there is also evidence that monoecy is a pathway from sequential hermaphroditism to dioecy.
See also
Hermaphrodite
Plant reproductive morphology
References
Plant reproductive system
Sexual system | Monoecy | [
"Biology"
] | 696 | [
"Sexual system",
"Sex"
] |
68,323,705 | https://en.wikipedia.org/wiki/Jorquette | The jorquette (horqueta; molinillo) is the point at which the vertical stem changes to fan growth on the cocoa tree (Theobroma cacao).
The whorl of lateral branches which grow out at an angle of approximately 45 degrees is called the jorquette.
For mostly of Theobroma sp, one of the two kinds of branch grows vertically upwards, (these are the trunk which grows until it is tall, and the chupons), and the other kind grows obliquely outwards, growing 3-5 lateral branches emerge apparently of the same level though each comes from a separate node.
Criollo cacao frequently produces 3 to 5 laterals in a jorquette which, however, show a distinct space between their points of origin on the main stem, whereas, in Forastero cacao, the laterals all come off at the same level. When the tree matures, the bases of the laterals form a single ring.
Subsequently, the tree development produce chupons from below the first jorquette to form another storey of fan branches from a second jorquette, a process which may be repeated. Selective pruning seeks for the jorquettes to achieve maximum light absorption efficiency.
References
Theobroma
Cocoa production
Plant morphology | Jorquette | [
"Biology"
] | 266 | [
"Plant morphology",
"Plants"
] |
68,326,427 | https://en.wikipedia.org/wiki/Ravna%20Vala | Ravna Vala is a primeval forest located on the mountains Igman and Bjelašnica in Bosnia and Herzegovina, about 20 km south-west of Sarajevo.
First time it was described in 1978.
Biology
Ravna Vala is located at an altitude of 1280 to 1450 meters on an area of 45 ha. The geological base is limestone-dolomite on which very heterogeneous soils have been developed. The main forest species are fir and beech, but spruce, maple and other deciduous trees occur in the admixture.
In addition to other wild animals, there is also a brown bear, which is the largest wild animal in Bosnia and Herzegovina.
References
External links
Old-growth forests
Geography of Bosnia and Herzegovina | Ravna Vala | [
"Biology"
] | 151 | [
"Old-growth forests",
"Ecosystems"
] |
68,329,220 | https://en.wikipedia.org/wiki/Gaping%20%28animal%20behavior%29 | Gaping is a common form of behavior in the animal kingdom, in which an animal opens its mouth widely and displays the interior of its mouth, for any of various purposes. This may be a form of deimatic behaviour, colloquially known as a startle display or threat display, as it enlarges the appearance of the animal, and for those with teeth it shows the threat that these represent. Animals may also use gaping as part of a courtship display, or to otherwise communicate with each other. Some animals have evolved features which make gaping behavior more visually effective. For example, "[i]n many species of reptile, the oral mucosa may be a bright color that serves to distract the predator". Gaping is part of the shark agonistic display, and is also found in snakes such as the cottonmouth, and in birds ranging from seagulls to puffins to roosters.
A number of species of bird use a gaping, open beak in their fear and threat displays. Some augment the display by hissing or breathing heavily, while others clap their beaks. In birds, the muscles that depress the lower mandible are usually weak, but certain birds have well-developed digastric muscles that aid in gaping actions. In most birds, these muscles are relatively small as compared to the jaw muscles of similarly sized mammals. Both male and female puffins use gaping as a prominent part of their threat display, with "a range of intensities" based on the situation, and with puffins engaging in territorial gape contests, where they mirror each other until one gives up and leaves, or an actual fight occurs.
Some animals are named for their tendency to use gaping as a threat display, or for the features that become apparent when making such a display. For example, the cottonmouth is so named because the white lining of its mouth is visible when gaping. Other snakes, such as the Western Massasauga, have been observed to engage in gaping behavior which "appears to be unrelated to any threat".
Gallery of images
References
Ethology
Antipredator adaptations | Gaping (animal behavior) | [
"Biology"
] | 426 | [
"Behavior",
"Ethology stubs",
"Biological defense mechanisms",
"Behavioural sciences",
"Antipredator adaptations",
"Ethology"
] |
68,329,749 | https://en.wikipedia.org/wiki/IBM%201015%20%28terminal%29 | The IBM 1015 is a display terminal for the IBM System/360. IBM suggested that it be used for phone-based customer support.
History
It was exhibited during the 1964 introduction of the IBM System/360 and included in the official System Summary. Other display devices introduced and co-marketed by IBM were the IBM 2250
and the IBM 2260.
Product description
The screen was round, and it sat forward and above a keyboard. The display area could hold 30 lines, each with up to 40 characters, selected from A–Z, 0–9, and 26 special characters. Output was 650 characters per second. It came with a desk. Up to ten 1015s could be connected to the IBM 1016 Control Unit or the IBM 1414 Input/Output Synchronizer.
References
Computer-related introductions in 1964 | IBM 1015 (terminal) | [
"Technology"
] | 167 | [
"Computing stubs"
] |
68,329,850 | https://en.wikipedia.org/wiki/Landman%20%28TV%20series%29 | Landman (stylized as LANDMAN) is an American drama television series created by Taylor Sheridan and Christian Wallace, based on the podcast Boomtown hosted by Wallace. Starring Billy Bob Thornton as a landman for an oil company, the show premiered November 17, 2024, on Paramount+.
Synopsis
Landman is set within the world of oilfields in West Texas, where "roughnecks and wildcat billionaires are fueling a boom so big it’s reshaping our climate, our economy, and our geopolitics." The lead character, Tommy Norris, can be abrasive, as is the out-of-town lawyer investigating a fatal accident early in the season.
Cast
Main
Billy Bob Thornton as Tommy Norris, a combination of a petroleum Landman and an Operations VP at an oil company.
Ali Larter as Angela Norris, Tommy's ex-wife, and Cooper and Ainsley's mother.
Jacob Lofland as Cooper Norris, Tommy and Angela's son, and Ainsley's brother who works for his dad as a roustabout.
Michelle Randolph as Ainsley Norris, Tommy and Angela's strong-willed daughter, and Cooper's sister.
Paulina Chavez as Ariana Medina, Elvio's wife
Kayla Wallace as Rebecca Falcone, a causation lawyer.
Mark Collie as Sheriff Walt Joeberg
James Jordan as Dale Bradley, a petroleum engineer.
Demi Moore as Cami Miller, Monty's wife and Tommy's friend
Jon Hamm as Monty Miller. The owner of M-Tex with a long personal and professional relationship with Tommy
Recurring
Colm Feore as Nathan, an oil company attorney and administrator.
Alex Meraz as Jimenez, the local Midland manager for an international drug cartel
Mustafa Speaks as Theodore "Boss" Ramone, the lead oil crewman on Cooper's second crew
Guest
Michael Peña as Armando Medina, a lead oil crewman who is training Cooper
Emilio Rivera as Luis Medina, an oil crewman, and Armando's and Elvio's uncle
Alejandro Akara as Elvio Medina, an oil crewman, Ariana's husband, Luis's nephew, and Armando's younger brother
Robyn Lively as Ellie, waitress at the Patch Cafe
Bart Johnson as Patrick Ramsey
Octavio Rodriguez as Antonio, a member of Boss's oil crew who dislikes Cooper and a cousin of everyone on Cooper's first crew
J.R. Villarreal as Manuel Lopez, another member of Boss's oil crew who also dislikes Cooper and another cousin of everyone on Cooper's first crew
Mitchell Slaggert as Ryder Sampson, Ainsley's new boyfriend
Marco Perella as Hank, a resident in a senior citizens home
Gail Cronauer as Beverly, a resident in a senior citizens home
Maxwell Caulfield as Governor of Texas
Ben Browder as Colonel Ivey of the Texas National Guard
Jerry Jones as himself
Tim DeZarn as Perry Hardin, a small parcel landholder with a dry oil well on his property
Matt Peters as Mel, a strip club owner
Michael Tow as Dr. Michaels, Monty's cardiac surgeon
Jim Meskimen as Alan, Monty's personal lawyer
Andy García as Galino, a member of Jimenez's cartel who disagrees with the way Jimenez's is running his territory
Episodes
Production
Development
In February 2022, Paramount+ ordered a television series adaptation of the podcast Boomtown titled Landman from screenwriter Taylor Sheridan. Billy Bob Thornton stars in the series. In May 2023, Jacob Lofland, Ali Larter, and Michelle Randolph joined the series. In January 2024, Kayla Wallace, James Jordan, Mark Collie, and Paulina Chávez joined the series as series regulars. In February 2024, it was reported that Jon Hamm joined the series. In April 2024, it was reported that Octavio Rodriguez and J.R. Villarreal joined the series as recurring characters.
In May 2024, it was confirmed by Demi Moore that the series had scored a second season, with production commencing in early 2025.
Filming
Filming started in and around Fort Worth, Texas, in February 2024 and concluded in June 2024. Filming locations included the headquarters of the American Association of Professional Landmen, the national association that represents land professionals, as well as the Fort Worth Petroleum Club and Texas Christian University.
Release
The first season launched on Sunday, November 17, 2024, with two episodes, and subsequent episodes of the 10-episode long first season will be available weekly on Sundays through January 12, 2025.
Reception
On the review aggregator website Rotten Tomatoes, the series has an approval rating of 76% based on 34 critic reviews, with an average rating of 6.2/10. The website's critics consensus reads, "Landman plumbs much of the same territory as other Taylor Sheridan-penned series, but having Billy Bob Thornton on hand turns this Texas crude into highly watchable fuel. Metacritic, which uses a weighted average, assigned a score of 60 out of 100 based on 20 critics, indicating "mixed or average" reviews.
Accolades
References
External links
on Paramount+
2020s American drama television series
2024 American television series debuts
American English-language television shows
Paramount+ original programming
Television series created by Taylor Sheridan
Television shows based on podcasts
Television shows filmed in Texas
Television shows set in Fort Worth, Texas
Texas culture
Works about petroleum | Landman (TV series) | [
"Chemistry"
] | 1,091 | [
"Petroleum",
"Works about petroleum"
] |
68,330,875 | https://en.wikipedia.org/wiki/Time%20in%20Libya | Time in Libya is given by a single time zone, officially denoted as Eastern European Time (EET; UTC+02:00). The zone is also known as Central Africa Time (CAT). Libya has observed EET since 5 November 2012, after it was announced in 2013 that Libya would be on permanent daylight saving time. Libya previously observed several different time zones as standard time and daylight saving time. For residents of western Libya, including Tripoli, solar time is usually one hour behind standard time.
Daylight saving time
Libya previously observed daylight saving time, moving one hour ahead from Central European Time (CET; UTC+01:00) to Central European Summer Time (CEST; UTC+02:00), each year from 1951 to 1956, 1982 to 1989, 1997, and 2013. Libya announced in 2013 that it would be on permanent daylight saving time.
IANA time zone database
In the IANA time zone database, Libya is given one zone in the file zone.tab – Africa/Tripoli. "LY" refers to the country's ISO 3166-1 alpha-2 country code. Data for Libya directly from zone.tab of the IANA time zone database; columns marked with * are the columns from zone.tab itself:
See also
Daylight saving time in Africa
List of time zones by country
List of UTC time offsets
References
External links
Current time in Libya at Time.is
Time in Libya at TimeAndDate.com
Time by country
Geography of Libya
Time in Africa | Time in Libya | [
"Physics"
] | 304 | [
"Spacetime",
"Physical quantities",
"Time",
"Time by country"
] |
68,330,978 | https://en.wikipedia.org/wiki/Sonic%20philosophy | Sonic philosophy or the philosophy of sound is a philosophical theory that proposes thinking sonically instead of thinking about sound. It is applied in ontology or the investigation of being and the determination of what exists. The materialist sonic philosophy is also considered part of aesthetic philosophy and traces the effect of sound on philosophy and draws from the notion that sound is a flux, event, and effect.
Background
Scholars cite the role of the naturalistic philosophies of Friedrich Nietzsche and Arthur Schopenhauer in the development of sonic philosophy. Both maintained that music and sound directly figure the world as it is in itself and that they serve as the primary forces and movements behind all natural change, tension, creation, and destruction. The latter's notion of music considers it as a direct expression of the will. In his early unpublished writings, Nietzsche wrote that the concept of the philosopher involves his attempts "to let all sounds of the world reverberate in him and to place this comprehensive sound outside himself into concepts". These thinkers' positions underscored the philosophical importance of sound as they articulate the presentation of an ontology that unsettles the ordinary conception of things. This ontology allows the investigation of being and the determination of what things exist.
Modern sound philosophy also emerged out of philosophical aesthetics as scholars address the question of whether sounds and sounding artworks can be treated in the same way as other arts (e.g. visual arts) are approached.
Sonic philosophy is considered in opposition to the Kantian philosophy of humanism since it challenges the suggestion that the world is only "for-us" and mediated by discourse. A modern conceptualization articulated the philosophy as based on the idea that sound is a flux, event, and effect. It is also part of a contemporary project that rejects the essentialist and phenomenological approach to sonic theory.
Sonic event
An element in the materialist philosophy of sound is the so-called sonic or acoustic event. In this conceptualization of sound, the event - beginning from a source and arriving at multiple locations - is always considered a public event, filling both ears and space. As an experience it shows that: 1) space is more than a conceptualization of materiality; 2) knowledge constitutes several voices; 3) circulation is affective and productive.
Flux
For thinkers such as John Cage and Max Neuhaus, sound and music are thought of as anonymous flux that is beyond the human contributions to it. According to Manuel De Landa, this particular notion of sound as a flux is critical in the conceptualization of all of nature and culture as a collection of flows that are captured and released through different isomorphic processes.
Philosophies
Christoph Cox proposed a modern conceptualization of sonic philosophy that drew from the works of Nietzsche and Gilles Deleuze. Citing the lack of theories on sound art, he developed a materialist sonic philosophy that approached theorizing aesthetics by beginning with sound. Cox maintained that this method upsets the ontology of "objects" and "beings" and underscores the materiality of sound. He stated:If we proceed from sound, we will be less inclined to think in terms of representation and signification, and to draw distinctions between culture and nature, human and nonhuman, mind and matter, the symbolic and the real, the textual and the physical, the meaningful and the meaningless. Instead, we might begin to treat artistic productions, not as complexes of signs or representations but complexes of forces materially inflected by other forces and force-complexes.
Thinkers who also developed their own sonic philosophy include Christof Migone who placed sound art within disparate and paradoxical contexts to address the sound's "physical diffuseness". In his work called Sonic Somatic: Performances of the Unsound Body, he also explored how sound shaped and disrupted the way art shifted from subject to object through to the abject. The work of Jing Wang cited Chinese philosophical concepts associated with sound such as resonance, shan shui, huanghu, and distributive monumentality as he explored the meaning and function of sound and expanded on the notion that "Chinese acoustics is acoustics of qi".
Sonic philosophy also underpinned a tactic called sonic warfare. It holds that, while sound is merely a vibration audible to humans and animals, it entails the perceptions of a human subject. In battle, sonic philosophy serves as a sonic intervention into thought, deploying concepts that are identified with sound, noise, music culture. These are then inserted into the weak spots of the history, philosophy, and psyche of the enemy.
References
Applied aesthetics
Acoustics | Sonic philosophy | [
"Physics"
] | 936 | [
"Classical mechanics",
"Acoustics"
] |
68,333,861 | https://en.wikipedia.org/wiki/Phosphide%20chloride | A Phosphide chloride is a mixed anion compound containing both phosphide (P3−) and chloride (Cl−) ions.
A common structural element is P73− which is called heptaphosphanortricyclane with a formal IUPAC name of heptaphosphatricyclo[2.2.1.02,6]heptane.
Group 12 elements, cadmium and mercury are in most of the known compounds.
List
References
Chlorides
Mixed anion compounds
Phosphides | Phosphide chloride | [
"Physics",
"Chemistry"
] | 115 | [
"Matter",
"Chlorides",
"Inorganic compounds",
"Mixed anion compounds",
"Salts",
"Ions"
] |
69,625,765 | https://en.wikipedia.org/wiki/History%20of%20research%20into%20the%20origin%20of%20life | The history of research into the origin of life encompasses theories about how life began, from ancient times with the philosophy of Aristotle through to the Miller-Urey experiment in 1952.
Panspermia
Panspermia is the hypothesis that life exists throughout the universe, distributed by meteoroids, asteroids, comets and planetoids. It does not attempt to explain how life originated, but shifts the origin to another heavenly body. The advantage is that life is not required to have formed on each planet it occurs on, but rather in a single location, and then spread across the galaxy to other star systems via cometary or meteorite impact.
Evidence for this is scant, but it finds some support in studies of Martian meteorites found in Antarctica and of extremophile microbes' survival in outer space tests. Terrestrial bacteria, particularly Deinococcus radiodurans, highly resistant to environmental hazards, could survive for at least three years in outer space, based on studies on the International Space Station.
An extreme speculation is that the biochemistry of life could have begun as early as 17 My (million years) after the Big Bang, during a supposedly habitable epoch, and that life may exist throughout the universe. Carl Zimmer has speculated that the chemical conditions, including boron, molybdenum and oxygen needed to create RNA, may have been better on early Mars than on early Earth. If so, life-suitable molecules originating on Mars would have later migrated to Earth via meteor ejections.
Spontaneous generation
General acceptance until 19th century
Traditional religion attributed the origin of life to deities who created the natural world. Spontaneous generation, the first naturalistic theory of abiogenesis, goes back to Aristotle and ancient Greek philosophy, and continued to have support in Western scholarship until the 19th century. The theory held that "lower" animals are generated by decaying organic substances. Aristotle stated that, for example, aphids arise from dew on plants, flies from putrid matter, mice from dirty hay, and crocodiles from rotting sunken logs. The basic idea was that life was continuously created as a result of chance events. In the 17th century, people began to question spontaneous generation, in works like Thomas Browne's Pseudodoxia Epidemica. His contemporary, Alexander Ross, erroneously rebutted him. In 1665, Robert Hooke published the first drawings of a microorganism. In 1676, Antonie van Leeuwenhoek drew and described microorganisms, probably protozoa and bacteria. Many felt their existence supported spontaneous generation, since they seemed too simplistic for sexual reproduction, and asexual reproduction: cell division had not yet been observed. Van Leeuwenhoek disagreed with spontaneous generation, and by the 1680s convinced himself, using experiments ranging from sealed and open meat incubation and the close study of insect reproduction, that the theory was incorrect. In 1668 Francesco Redi showed that no maggots appeared in meat when flies were prevented from laying eggs. In 1768, Lazzaro Spallanzani demonstrated that microbes were present in the air, and could be killed by boiling. In 1861, Louis Pasteur's experiments demonstrated that organisms such as bacteria and fungi do not spontaneously appear in sterile, nutrient-rich media, but could only appear by invasion from without.
Considered disproven in 19th century
By the middle of the 19th century, biogenesis was supported by so much evidence that spontaneous generation had been effectively disproven. Pasteur remarked, about an 1864 finding of his, "Never will the doctrine of spontaneous generation recover from the mortal blow struck by this simple experiment." This gave a mechanism by which life diversified from a few simple organisms to a variety of complex forms. Today, scientists agree that all current life descends from earlier life, which has become progressively more complex and diverse through Charles Darwin's mechanism of evolution by natural selection.
Darwin wrote to J.D. Hooker on 29 March 1863 stating that "It is mere rubbish, thinking at present of the origin of life; one might as well think of the origin of matter". In On the Origin of Species, he had referred to life having been "created", by which he "really meant 'appeared' by some wholly unknown process", but had soon regretted using the Old Testament term "creation".
Oparin: Primordial soup hypothesis
There is no single generally accepted model for the origin of life. Scientists have proposed several plausible hypotheses which share some common elements. While differing in details, these hypotheses are based on the framework laid out by Alexander Oparin (in 1924) and John Haldane (in 1929), that the first molecules constituting the earliest cells . . . were synthesized under natural conditions by a slow process of molecular evolution, and these molecules then organized into the first molecular system with properties with biological order". Oparin and Haldane suggested that the atmosphere of the early Earth may have been chemically reducing in nature, composed primarily of methane (CH4), ammonia (NH3), water (H2O), hydrogen sulfide (H2S), carbon dioxide (CO2) or carbon monoxide (CO), and phosphate (PO43−), with molecular oxygen (O2) and ozone (O3) either rare or absent. According to later models, the atmosphere in the late Hadean period consisted largely of nitrogen (N2) and carbon dioxide, with smaller amounts of carbon monoxide, hydrogen (H2), and sulfur compounds; while it did lack molecular oxygen and ozone, it was not as chemically reducing as Oparin and Haldane supposed.
No new notable research or hypothesis on the subject appeared until 1924, when Oparin reasoned that atmospheric oxygen prevents the synthesis of certain organic compounds that are necessary building blocks for life. In his book The Origin of Life, he proposed (echoing Darwin) that the "spontaneous generation of life" that had been attacked by Pasteur did, in fact, occur once, but was now impossible because the conditions found on the early Earth had changed, and preexisting organisms would immediately consume any spontaneously generated organism. Oparin argued that a "primeval soup" of organic molecules could be created in an oxygenless atmosphere through the action of sunlight. These would combine in ever more complex ways until they formed coacervate droplets. These droplets would "grow" by fusion with other droplets, and "reproduce" through fission into daughter droplets, and so have a primitive metabolism in which factors that promote "cell integrity" survive, and those that do not become extinct. Many modern theories of the origin of life still take Oparin's ideas as a starting point.
About this time, Haldane suggested that the Earth's prebiotic oceans (quite different from their modern counterparts) would have formed a "hot dilute soup" in which organic compounds could have formed. Bernal called this idea biopoiesis or biopoesis, the process of living matter evolving from self-replicating but non-living molecules, and proposed that biopoiesis passes through a number of intermediate stages.
Robert Shapiro has summarized the "primordial soup" theory of Oparin and Haldane in its "mature form" as follows:
The early Earth had a chemically reducing atmosphere.
This atmosphere, exposed to energy in various forms, produced simple organic compounds ("monomers").
These compounds accumulated in a "soup" that may have concentrated at various locations (shorelines, oceanic vents etc.).
By further transformation, more complex organic polymers—and ultimately life—developed in the soup.
John Bernal
John Bernal showed that based upon this and subsequent work there is no difficulty in principle in forming most of the molecules we recognize as the necessary molecules for life from their inorganic precursors. The underlying hypothesis held by Oparin, Haldane, Bernal, Miller and Urey, for instance, was that multiple conditions on the primeval Earth favoured chemical reactions that synthesized the same set of complex organic compounds from such simple precursors.
Bernal coined the term biopoiesis in 1949 to refer to the origin of life. In 1967, he suggested that it occurred in three "stages":
the origin of biological monomers
the origin of biological polymers
the evolution from molecules to cells
Bernal suggested that evolution commenced between stages 1 and 2. Bernal regarded the third stage, in which biological reactions were incorporated behind a cell's boundary, as the most difficult. Modern work on the way that cell membranes self-assemble, and the work on micropores in various substrates, may be a key step towards understanding the development of independent free-living cells.
Miller–Urey experiment
In 1952, Stanley Miller and Harold Urey performed an experiment that demonstrated how organic molecules could have spontaneously formed from inorganic precursors under conditions like those posited by the Oparin-Haldane hypothesis. The Miller–Urey experiment used a highly reducing mixture of gases—methane, ammonia, and hydrogen, as well as water vapor—to form simple organic monomers such as amino acids. The mixture of gases was cycled through an apparatus that delivered electrical sparks to the mixture. After one week, it was found that about 10% to 15% of the carbon in the system was then in the form of a racemic mixture of organic compounds, including amino acids, which are the building blocks of proteins. This provided direct experimental support for the second point of the "soup" theory, and it is around the remaining two points of the theory that much of the debate centers. A 2011 reanalysis of the saved vials has uncovered more biochemicals than originally discovered in the 1950s, including 23 amino acids, not just five.
2020 studies suggest that the primeval atmosphere of the Earth was much different than the conditions used in the Miller-Urey studies.
References
Sources
Proceedings of the SPIE held at San Diego, CA, 31 July–2 August 2005
Origin of life | History of research into the origin of life | [
"Biology"
] | 2,046 | [
"Biological hypotheses",
"Origin of life"
] |
69,626,564 | https://en.wikipedia.org/wiki/Owkin | Owkin is an AI biotech company that uses artificial intelligence to identify new treatments, optimize clinical trials and develop AI diagnostics. The company uses federated learning, a type of privacy preserving technology, to access multimodal patient data from academic institutions and hospitals to train its AI models for drug discovery, development, and diagnostics. Owkin has collaborated with pharmaceutical companies around the world to improve their therapeutic programs.
History
Owkin was founded in 2016, by Thomas Clozel, a clinical research doctor and son of Jean-Paul and Martine Clozel founders of Swiss biotech Actelion, and Gilles Wainrib, a professor of Artificial Intelligence.
Owkin has raised over $255 million and became a ‘unicorn’ – a startup valued at more than $1 billion – in November 2021 through a $180 million investment from French biopharma company Sanofi.
Technologies
Federated learning
Owkin uses federated learning, a decentralized machine learning technique, to train machine learning models with multiple data providers. Federated learning allows data providers to collaborate without moving or sharing their data.
The MELLODDY project, an initiative that included Owkin, 10 pharmaceutical companies, and six other partners, applied federated learning to train AI on datasets without having to share proprietary data. The aim was to improve drug discovery and they built a shared platform called MELLODDY (Machine Learning Ledger Orchestration for Drug Discovery). The first results of the project were published in July 2022.
Transfer learning
Transfer learning is a machine learning technique that allows a model pre-trained on one task to be used on another related task. Owkin uses transfer learning to work on very small datasets. Owkin's model (CHOWDER) is able to understand high-level graphic patterns, such as tumors, that are themselves relying on very low-level visual patterns, in order to fully learn the tumor's visual pattern.
Products and Services
MSIntuit CRC
MSIntuit CRC is an AI-powered digital pre-screening diagnostic tool to improve colorectal cancer diagnosis and treatment. It screens patients for microsatellite instability (MSI), which is a key genomic biomarker in colorectal cancer. MSIntuit CRC is approved for use across the European Union. It underwent a blind validation in 2023, made possibly partly by its availability within Medipath, the largest pathology lab network in France.
Dx RlapsRisk BC
Dx RlapsRisk BC uses AI to predict if breast cancer patients will relapse within a few years of initial treatment. It is used by pathologists and oncologists to help determine the right treatment pathway for breast cancer patients.
Partnerships
Amgen
Owkin collaborated with Amgen to test the ability of AI to improve cardiovascular prediction.
Sanofi
In November 2021 Owkin entered a strategic alliance with Sanofi. The alliance included a $180 million equity investment, and a $90 million discovery and development partnership focused on Sanofi’s oncology efforts in four different cancers. Sanofi used Owkin’s technology to find new biomarkers and therapeutic targets, build prognostic models, and predict response to treatment.
Bristol-Myers Squibb
In June 2022, Owkin entered a strategic alliance with Bristol-Myers Squibb to help them design potentially more precise and efficient clinical trials. The collaboration initially focused on cardiovascular disease, and has the potential to expand into projects in other therapeutic areas.
MSD
In December 2023, Owkin entered a strategic alliance with MSD to develop and commercialize AI-powered digital pathology diagnostics for the EU market that could be used to identify patients suitable for immunotherapies.
Servier
In October 2023, Owkin and Servier started a multi-year partnership focused on developing “better-targeted therapies” in oncology and other disease areas. The partnership’s first two projects were in translational medicine and digital pathology.
MOSAIC
MOSAIC (Multi Omic Spatial Atlas in Cancer) was formed by Owkin, Nanostring Technologies, the University of Pittsburgh, Gustave Roussy, Lausanne University Hospital, Uniklinikum Erlangen/Friedrich-Alexander-Universität Erlangen-Nürnberg, and Charité-Universitätsmedizin Berlin. It uses spatial omics, multimodal patient data, and artificial intelligence, and aims to “offer unprecedented information on the structure of tumors” and guide new treatments.
Publications
Owkin’s research on AI/ML has led to a number of publications that focus on machine learning methodologies and the development of predictive models for different disease areas, mainly oncology.
Courtiol, Pierre et al. “Deep learning-based classification of mesothelioma improves prediction of patient outcome”, Nat Med 25, 1519–1525 (2019)
Schmauch, Benoît et al. “A deep learning model to predict RNA-Seq expression of tumours from whole slide images”, Nature Communications volume 11, Article number: 3877 (2020)
Jean Ogier du Terrail et al. “Federated learning for predicting histological response to neoadjuvant chemotherapy in triple-negative breast cancer" Nat Med (2023). 10.1038/s41591-022-02155
Saiilard et al., “Pacpaint: a histology-based deep learning model uncovers the extensive intratumor molecular heterogeneity of pancreatic adenocarcinoma” Nat Commun 14, 3459 (2023)
Saillard et al., “Validation of MSIntuit as an AI-based pre-screening tool for MSI detection from colorectal cancer histology slides” Nature Communications 14, 6695 (2023)
Saillard et al., "Predicting Survival After Hepatocellular Carcinoma Resection Using Deep Learning on Histological Slides" Hepatology 72 (2020)
Awards
2019 AI For Health challenge
2020 Galien Foundation Best Digital Health Product Nominee
2021 Tech For Good Awards - “Health” category
2021 Member Recognition Awards from the French American Chamber of Commerce - Technology, Startups & Entrepreneurs Committee Awards
References
Biotechnology companies
Artificial intelligence companies
Companies established in 2016 | Owkin | [
"Engineering",
"Biology"
] | 1,291 | [
"Biotechnology organizations",
"Biotechnology companies"
] |
69,627,157 | https://en.wikipedia.org/wiki/The%20Green%20Book%20%28immunisation%20guidance%2C%20UK%29 | Immunisation against infectious disease, popularly known as The Green Book, provides information on vaccines for vaccine-preventable diseases. It acts as a guide to the UK's vaccination schedule for health professionals and health departments that give vaccines in the United Kingdom.
The first two editions were published in 1992 and 1996. A third edition in 2006, was the last to appear in print. Updates have since been added by its clinical editors through advice and recommendations from the Joint Committee on Vaccination and Immunisation (JCVI) and appear only online as individual chapters via the immunisation section of the GOV.UK website. As of 2021 it includes updates on COVID-19.
Purpose
Immunisation against infectious disease is popularly known as The Green Book, to provide information on the UK's vaccination schedule and vaccines for vaccine preventable infectious diseases. It is a guide for health professionals and health departments that give vaccines in the UK. Updates are added by its clinical editors through advice and recommendations from the Joint Committee on Vaccination and Immunisation (JCVI), as accepted by the Secretaries of State. Larger updates may also need consultations with UK health departments and public health bodies, MHRA, vaccine manufacturers, NHS England, National Travel Health Network and Centre (NaTHNaC), as well as the clinical editors.
Publication
The first two editions were published by the HMSO in 1992 and 1996. The third edition, published by The Stationery Office in 2006, replaced the 1996 edition and was the last to appear in print.
2006 edition
The 2006 edition of The Green book has 468 pages, divided generally into two parts, preceded by a contents page, acknowledgements and preface, and followed by two indexes, one of vaccines by proprietary name and the other of vaccines by common name.
Part one: principles, practices and procedures
Part one, titled "principles, practice and procedures", has 12 chapters which include how vaccines work, storage and distribution, vaccine safety and adverse events, immunisation schedule and immunisation of healthcare and laboratory staff. How to give a vaccine is described in chapter four, common side effects in chapter eight and how to fill in a yellow card in chapter nine (updated 2013).
Immunity and how vaccines work
Consent
Storage, distribution and disposal of vaccines
Immunisation procedures
Immunisation by nurses and other health professionals
Contraindications and special considerations
Immunisation of individuals with underlying medical conditions
Vaccine safety and adverse events following immunisation
Surveillance and monitoring for vaccine safety
Vaccine Damage Payment Scheme
Immunisation schedule
Immunisation of healthcare and laboratory staff
Part two: diseases, vaccinations and vaccines
Diseases and their vaccines are listed in alphabetical order and include all vaccines recommended in the routine immunisation programme for all children in the UK. Vaccine requirements for travellers and for contacts of people with infectious disease are included. The 2006 edition incorporated the then new vaccines for meningococcal group C and pneumococcal infections, included the cessation of the school's BCG programme and the introduction of the Hib-MenC booster at 12 months of age.
Diseases included:
Anthrax
Cholera
Diphtheria
Haemophilus influenzae type b (Hib)
Hepatitis A
Hepatitis B
Influenza
Japanese encephalitis
Measles
Meningococcal
Mumps
Pertussis
Pneumococcal
Polio
Rabies
Rubella
Smallpox and vaccinia
Tetanus
Tick-borne encephalitis
Tuberculosis
Typhoid
Varicella
Yellow fever
Online version
The online version was published in 2013. Updates appear only online as individual chapters via the immunisation section of the GOV.UK website. These have included respiratory syncytial virus and rotavirus in 2015, and human papillomavirus in 2019. As of 2021, the online version stays divided into two parts, in the same way as the 2006 edition, and includes updates on shingles and COVID-19.
According to Andrew Pollard, The Green Book should be "bookmarked" in all child clinics and notes that similar information can be obtained from the US Centers for Disease Control and Prevention website. It is a recommended source by the Royal College of Paediatrics and Child Health.
Editors
1996 - David Salisbury, Norman T. Begg
2006 - David Salisbury, Mary Ramsay, Karen Noakes
2021 - Mary Ramsay
References
External links
Vaccination
Medical books | The Green Book (immunisation guidance, UK) | [
"Biology"
] | 902 | [
"Vaccination"
] |
69,627,448 | https://en.wikipedia.org/wiki/Acoustic%20epidemiology | Acoustic epidemiology refers to the study of the determinants and distribution of disease. It also refers to the analysis of sounds produced by the body (coughs, sneezes, wheezing, etc.) through a single tool or a combination of diagnostic tools.
In many cases, epidemiologists have worked across multiple disciplines and used different technologies in order to find answers pertaining to disease distribution. For example, in the 1800s, John Snow determined that cholera was plaguing Europe through contaminated water. This led to the decision to remove a pump that was the cause of this contamination, thus effectively ending the epidemic. More broadly, Snow's epidemiological efforts led to the development of sewage drainage and water purifying systems in other areas.
As COVID-19 developed, genomic epidemiologists began using whole genomes to study the disease. On the CDC's website, they have posted a “COVID-19 Genomic Epidemiology Toolkit”, which provides a means to expand the field of genomic epidemiology with regards to COVID-19 within state and local populations.
Acoustic epidemiology is a field that studies bodily sounds, such as coughs and breath sounds, in order to better identify determinants and distribution of disease. Following in the footsteps of epidemiological tools and efforts such as those outlined above, acoustic epidemiology is concerned with using body sound data to improve disease surveillance capabilities for COVID-19 and any other applicable diseases of the future.
Clinical relevance
Being that epidemiology is a population-based area of study, findings from acoustic disease surveillance are important on a large scale, and have far-reaching implications for society as a whole. Cough and breath sounds provide rich epidemiological data.
Baseline Measurements and Deviations
Studying respiratory sounds and identifying deviations from baseline is an invaluable epidemiologic tool. On a community and population level, this can help to determine to what extent a disease may be spreading or changing. One of the major themes of concern throughout the COVID-19 pandemic has been travel safety, hotspots, and outbreaks in certain areas.
Acoustic Epidemiology Through Use of Smartphone Apps
As a means to overcome some of the restrictions imposed by the COVID-19 pandemic, smartphone apps were developed to capture and analyze respiratory health data safely.
In a 2020-2021 study of acoustic epidemiology, in Navarra, Spain, the Hyfe app was used to track respiratory sounds in over 800 study participants.
Syndromic Surveillance
Syndromic surveillance is a complementary, and potentially faster method of health data collection and analysis as compared to standard methods of public health monitoring.
Examples of Syndromic Surveillance
Instances of syndromic surveillance are easy to find. Examples include:
Logs that record missed school or work due to illness
Symptoms recorded on patients in emergency rooms
How often certain lab tests are ordered and performed
Bias in Syndromic Surveillance
Sources for syndromic surveillance may be biased, as they vary based on healthcare access in a given area. Therefore, some have questioned whether certain common methods of syndromic surveillance are truly representative of the larger population.
The future of acoustic epidemiology
The value of being able to track signs of deviations from baseline with regards to respiratory sounds at a population level is becoming clear through research. Epidemiologists predict that respiratory viruses could continue to be a problem in the future. Therefore, effective monitoring of acoustic data will need to be easy, affordable, and available on a wide scale.
See also
Cough Tracking
Respiratory Health
Pulmonary System
References
Epidemiology
Epidemiological study projects | Acoustic epidemiology | [
"Environmental_science"
] | 756 | [
"Epidemiology",
"Environmental social science"
] |
69,628,781 | https://en.wikipedia.org/wiki/Pairwise%20compatibility%20graph | In graph theory, a graph is a pairwise compatibility graph (PCG) if there exists a tree and two non-negative real numbers such that each node of has a one-to-one mapping with a leaf node of such that two nodes and are adjacent in if and only if the distance between and are in the interval .
The subclasses of PCG include graphs of at most seven vertices, cycles, forests, complete graphs, interval graphs and ladder graphs. However, there is a graph with eight vertices that is known not to be a PCG.
Relationship to phylogenetics
Pairwise compatibility graphs were first introduced by Paul Kearney, J. Ian Munro and Derek Phillips in the context of phylogeny reconstruction. When sampling from a phylogenetic tree, the task of finding nodes whose path distance lies between given lengths is equivalent to finding a clique in the associated PCG.
Complexity
The computational complexity of recognizing a graph as a PCG is unknown as of 2020. However, the related problem of finding for a graph and a selection of non-edge relations a PCG containing as a subgraph and with none of the edges in is known to be NP-hard.
The task of finding nodes in a tree whose paths distance lies between and is known to be solvable in polynomial time. Therefore, if the tree could be recovered from a PCG in polynomial time, then the clique problem on PCGs would be polynomial too. As of 2020, neither of these complexities is known.
References
Graph families
Computational phylogenetics | Pairwise compatibility graph | [
"Biology"
] | 311 | [
"Bioinformatics",
"Phylogenetics",
"Computational phylogenetics",
"Genetics techniques"
] |
69,629,099 | https://en.wikipedia.org/wiki/Katherine%20Lemos | Katherine Andrea Lemos is an American safety professional and the former chairperson and CEO of the U.S. Chemical Safety and Hazard Investigation Board (CSB).
Early life
Katherine Lemos was born to John Curtis and Laura Curtis. Her father was a United States Air Force and Air National Guard pilot and a commercial airline pilot. Lemos started flight lessons at the age of fourteen, at which time her father required her to read National Transportation Safety Board publications to learn about aviation safety and accidents.
Lemos earned a B.B.A. in business management from Belmont University, a M.S. in behavioral counseling from California Lutheran University, and a Ph.D. in social psychology from University of Iowa. She also worked as a postdoctoral researcher at University of Iowa Operator Performance Laboratory and as a NASA Faculty Fellow at Langley Research Center.
Lemos is a pilot and certified flight instructor.
Career
Prior to her appointment to CSB, Lemos worked at Northrop Grumman from 2014 to 2020, serving as the company's director of autonomy and director of programs for the aerospace sector. She had previously worked as a technical leader and program manager for aviation safety at the Federal Aviation Administration and as an accident investigator and later Special Assistant to Vice Chairman of the Board of the National Transportation Safety Board. She had also held academic positions at University of Maryland and Instituto Tecnológico de Aeronáutica.
Lemos has specialized in system safety, accident investigation, and human factors. At the time she was nominated to CSB, she had no experience in chemical manufacturing or refinery operations, fields which fall under the purview of CSB investigation.
Chemical Safety Board
Katherine Lemos was nominated by President Donald Trump to be a member of CSB on June 13, 2019. On July 22, she was nominated by President Trump to serve concurrent five-year appointments as chairperson and CEO of CSB. At the time, the CSB's five-seat board had only three members, one of whom would leave in December 2019. The problem of vacancies in the CSB board was noted by a May 2019 Environmental Protection Agency Office of Inspector General report to be detrimental to CSB's ability to function effectively.
A hearing on her nomination was held by the United States Senate Committee on Environment and Public Works in September 2019. Lemos received bipartisan support from committee members during her nomination. Her appointment was confirmed by the Senate by unanimous consent on March 23, 2020. Senator John Barrasso said "it was critical the Senate confirm Dr. Lemos to provide a working quorum to the board"; at the time of Lemos's confirmation, the CSB board had only one member, Kristen Kulinowski, and only eight investigators. She began her tenure on April 23, 2020.
Four days after Lemos's term began, Kulinowski announced that she would resign from CSB on May 1, ending the CSB's brief quorum. At this time, CSB had ten unfilled investigator positions. Thereafter, Lemos declared that she could operate as a "quorum of one", citing a legal opinion from the CSB general counsel allowing her to unilaterally run the CSB. A July 2020 Environmental Protection Agency Office of Inspector General report concluded that it remained an open question whether a single CSB board member may constitute a quorum, as doing so would impair the segregation of duties mandated by the Government Accountability Office.
In May 2021, Public Employees for Environmental Responsibility criticized Lemos for accruing $33,000 in travel expenses and $20,000 in office renovations, and for hiring a senior advisor from Northrop Grumman for an undisclosed salary.
In a September 2021 hearing before the United States House Energy Subcommittee on Oversight and Investigations, Lemos testified that the CSB is "on an upward trend". She said that she intended to expand the staff of CSB to 61 people by September 2023.
In September 2021, the Senate Committee on Environment and Public Works approved the nominations of three new board members of the CSB, and in December 2021, two members were confirmed, Steve Owens and Sylvia Johnson. Once seated on the board in February 2022, Owens and Johnson openly disagreed with changes Lemos approved to a board order, which resulted in an expansion of the chairperson's authority. They attempted a procedural vote to make further changes to the order, but Lemos tabled the vote for a public meeting, which ultimately did not occur due to her resignation.
Lemos submitted her letter of resignation to the White House in June 2022, citing lost confidence in the board's focus on the agency's mission. Her resignation became effective on July 22, 2022.
In June 2023, the EPA Inspector General released a report stating that Lemos violated federal regulations for her use of board funds for travel, office refurbishment, and media training, but did not violate restrictions placed by a continuing resolution and did not violate regulations for the hiring of senior aides. Senator Chuck Grassley wrote a letter to Lemos requesting that she repay the money indicated as improperly spent in the report.
References
United States Chemical Safety and Hazard Investigation Board
Belmont University alumni
California Lutheran University alumni
University of Iowa alumni
First Trump administration personnel
Living people
1967 births | Katherine Lemos | [
"Chemistry"
] | 1,070 | [
"United States Chemical Safety and Hazard Investigation Board"
] |
69,629,542 | https://en.wikipedia.org/wiki/Voyager-EUS2 | Voyager-EUS2 is a supercomputer built by Microsoft Azure, capable of 39.531 petaflops, and is ranked 14th in the TOP500 as of November 2022. Voyager-EUS2 runs from Microsoft Azure East US 2 region and it utilizes 253,440 cores on AMD EPYC CPUs along with an NVIDIA A100 GPU with 80GB memory and a Mellanox HDR Infiniband for data transfer running on Linux distribution.Si
See also
TOP500
References
Supercomputers | Voyager-EUS2 | [
"Technology"
] | 114 | [
"Supercomputers",
"Computing stubs",
"Supercomputing",
"Computer hardware stubs"
] |
69,629,755 | https://en.wikipedia.org/wiki/HD%2027022 | HD 27022, also known as HR 1327, is a star located in the northern circumpolar constellation Camelopardalis. The object has also been designated as 20 H. Camelopardalis, but is not commonly used in modern times. It has an apparent magnitude of 5.27, allowing it to be faintly visible to the naked eye. Based on parallax measurements from Gaia DR3, the star has been estimated to be 347 light years away. It appears to be approaching the Solar System, having a heliocentric radial velocity of .
This is a solitary, yellow giant with a stellar classification of G4 III. It has alternatively been classified as G5 IIb wk, indicating a bright giant with weak lines. HD 27022 is currently on the horizontal branch located on the warm end of the red clump, a region of the said branch filled with metal-rich giant stars. It has 2.88 times the mass of the Sun but at the age of 444 million years, it has expanded to 10.71 times its girth. It radiates 75.9 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of . Like most giants, it spins rather slowly, having a projected rotational velocity of km/s. Kinematically, it belongs to the halo of the Ursa Major moving group.
References
G-type giants
G-type bright giants
Camelopardalis
027022
Durchmusterung objects
1327
020266
Ursa Major moving group | HD 27022 | [
"Astronomy"
] | 319 | [
"Camelopardalis",
"Constellations"
] |
69,629,864 | https://en.wikipedia.org/wiki/Austin%20250hp%20gas%20turbine | The Austin 250hp gas turbine was a free turbine turboshaft engine developed by Dr John Weaving at the Austin Motor Company. It was a development of an earlier engine that had been used in the experimental Austin Princess car TUR1. Various uses for the engine were suggested, such as mobile power unit and hospital backup generator, but it did not find any commercial use. More powerful derivates were developed but these also found no uses
References
1950s turboshaft engines
Cars powered by gas turbines
250hp gas turbine | Austin 250hp gas turbine | [
"Engineering"
] | 102 | [
"Mechanical engineering stubs",
"Mechanical engineering"
] |
69,630,959 | https://en.wikipedia.org/wiki/HD%2023277 | HD 23277 (HR 1138) is a spectroscopic binary located in the northern circumpolar constellation Camelopardalis. With a combined apparent magnitude of 5.39, it is faintly visible to the naked eye under ideal conditions. This star is located at a distance of 372 light years, but is drifting away at a rate of .
The primary has a classification of kA2hA6VmA7, which indicates that it has the calcium K-line of an A2 star, but its hydrogen lines suggest a class of A6 V and metallic lines of an A7 star. At present it has 2.38 times the Sun's mass, and 3.55 times its radius. It radiates at 59.7 times the luminosity of the Sun from its photosphere at an effective temperature of , which gives it a white hue. The companion has 2.11 times the Sun's mass, which suggests it is an A-type main-sequence star like the primary. Both stars spin at a projected rotational velocity of 25 km/s, common for an Am star.
References
Am stars
Spectroscopic binaries
A-type main-sequence stars
Durchmusterung objects
023277
017854
1138
Camelopardalis | HD 23277 | [
"Astronomy"
] | 264 | [
"Camelopardalis",
"Constellations"
] |
69,631,927 | https://en.wikipedia.org/wiki/Neonectria%20faginata | Neonectria faginata is a species of fungus that affects Beech trees in North America. Neonectria faginata, along with Neonectria ditissima, are the cause of beech bark disease in trees that have already been affected by beech scale Cryptococcus fagisuga.
References
Nectriaceae
Fungus species | Neonectria faginata | [
"Biology"
] | 68 | [
"Fungi",
"Fungus species"
] |
69,632,821 | https://en.wikipedia.org/wiki/YugabyteDB | YugabyteDB is a high-performance transactional distributed SQL database for cloud-native applications, developed by Yugabyte.
History
Yugabyte was founded by ex-Facebook engineers Kannan Muthukkaruppan, Karthik Ranganathan, and Mikhail Bautin. At Facebook, they were part of the team that built and operated Cassandra and HBase for workloads such as Facebook Messenger and Facebook's Operational Data Store.
The founders came together in February 2016 to build YugabyteDB.
YugabyteDB was initially available in two editions: community and enterprise. In July 2019, Yugabyte open-sourced previously commercial features and launched YugabyteDB as open-source under the Apache 2.0 license.
Funding
In October 2021, five years after the company's inception, Yugabyte closed a $188 Million Series C funding round to become a Unicorn start-up with a valuation of $1.3Bn
Architecture
YugabyteDB is a distributed SQL database that aims to be strongly transactionally consistent across failure zones (i.e. ACID compliance]. Jepsen testing, the de facto industry standard for verifying correctness, has never fully passed, mainly due to race conditions during schema changes. In CAP Theorem terms YugabyteDB is a Consistent/Partition Tolerant (CP) database.
YugabyteDB has two layers, a storage engine known as DocDB and the Yugabyte Query Layer.
DocDB
The storage engine consists of a customized RocksDB combined with sharding and load balancing algorithms for the data. In addition, the Raft consensus algorithm controls the replication of data between the nodes. There is also a Distributed transaction manager and Multiversion concurrency control (MVCC) to support distributed transactions.
The engine also exploits a Hybrid Logical Clock that combines coarsely-synchronized physical clocks with Lamport clocks to track causal relationships.
The DocDB layer is not directly accessible by users.
YugabyteDB Query Layer
Yugabyte has a pluggable query layer that abstracts the query layer from the storage layer below. There are currently two APIs that can access the database:
YSQL is a PostgreSQL code-compatible API based around v11.2. YSQL is accessed via standard PostgreSQL drivers using native protocols. It exploits the native PostgreSQL code for the query layer and replaces the storage engine with calls to the pluggable query layer. This re-use means that Yugabyte supports many features, including:
Triggers & Stored Procedures
PostgreSQL extensions that operate in the query layer
Native JSONB support
YCQL is a Cassandra-like API based around v3.10 and re-written in C++. YCQL is accessed via standard Cassandra drivers using the native protocol port of 9042. In addition to the 'vanilla' Cassandra components, YCQL is augmented with the following features:
Transactional consistency - unlike Cassandra, Yugabyte YCQL is transactional.
JSON data types supported natively
Tables can have secondary indexes
Currently, data written to either API is not accessible via the other API, however YSQL can access YCQL using the PostgreSQL foreign data wrapper feature.
The security model for accessing the system is inherited from the API, so access controls for YSQL look like PostgreSQL, and YCQL looks like Cassandra access controls.
Cluster-to-cluster replication
In addition to its core functionality of distributing a single database, YugabyteDB has the ability to replicate between database instances. The replication can be one-way or bi-directional and is asynchronous.
One-way replication is used either to create a read-only copy for workload off-loading or in a read-write mode to create an active-passive standby.
Bi-directional replication is generally used in read-write configurations and is used for active-active configurations, geo-distributed applications, etc.
Migration tooling
Yugabyte also provides YugabyteDB Voyager, tooling to facilitate the migration of Oracle and other similar databases to YugabyteDB. This tool supports the migration of schemas, procedural code and data from the source platform to YugabyteDB.
See also
Cloud database
Distributed SQL
Comparison of relational database management systems
Comparison of object–relational database management systems
Cloud native computing
Database management system
List of databases using MVCC
List of relational database management systems
CockroachDB
TiDB
References
External links
Slack community
Cloud databases
Database companies
Bigtable implementations
Database-related software for Linux
NewSQL
Distributed computing
Computer systems
Software companies of the United States
Companies based in Silicon Valley | YugabyteDB | [
"Engineering"
] | 987 | [
"Reliability engineering",
"Fault tolerance"
] |
69,632,903 | https://en.wikipedia.org/wiki/3D%20concrete%20printing | 3D concrete printing, or simply concrete printing, refers to digital fabrication processes for cementitious materials based on one of several different 3D printing technologies. 3D-printed concrete eliminates the need for formwork, reducing material waste and allowing for greater geometric freedom in complex structures. With recent developments in mix design and 3D printing technology over the last decade, 3D concrete printing has grown exponentially since its emergence in the 1990s. Architectural and structural applications of 3D-printed concrete include the production of building blocks, building modules, street furniture, pedestrian bridges, and low-rise residential structures.
History
Automating building processes has been an area of research in architecture and civil engineering since the 20th century. The earliest approaches focused on automating masonry. In 1904, a patent for a brick-laying machine was granted to John Thomas in the US. By the 1960s, the technology developed significantly and functional equipment, such as the Motor-Mason, were in use on building sites.
At the same time, automating concrete construction processes was also being developed. Slip forming, a widely used technique today for building vertical concrete cores for high-rise buildings, was developed in the early 20th century for building silos and grain elevators. The concept was pioneered by James MacDonald, of MacDonald Engineering Chicago, and published by Milko S. Ketchum in an illustrated book: The Design of Walls, Bins, and Grain Elevators in 1907. Later, MacDonald published a scientific paper: Moving Forms for Reinforced Concrete Storage Bins in 1911. Finally, on 24 May 1917, MacDonald was granted a US patent for a device to move and elevate a concrete form in a vertical plane.
Innovations in the automation of concreting processes continued throughout the 20th century. 3D printing processes were first developed in the 1980s for photopolymers and thermoplastics. For some time, 3D printing technology was limited to high-value-adding sectors such as aerospace and biomedical industries due to the high cost of materials. However, as the knowledge base for 3D printing grew, new additive manufacturing processes were developed for other materials, including for concrete. 3D printed concrete technology originated from Rensselaer Polytechnic Institute (RPI) in New York when Joseph Pegna first applied additive manufacturing to concrete in 1997. This experiment was just a proof of concept, but Pegna recognized the developing robotics industry and saw it as an opportunity to automate the construction process, while also decreasing costs and waste production. Pegna's research would later become the basis for binder jetting, or powder based 3D concrete printing.
In 1998, Behrokh Khoshnevis at the University of Southern California developed Contour Crafting, which was the first layered extrusion device for concrete. The system used a computer-controlled crane to automate the pouring process and was capable of creating smooth contour surfaces. Khoshnevis initially designed this system to serve as rapid home construction for natural disaster recovery, and he claimed that the system could complete a home in a single day. With innovations in materials, mix design, and printing technology, researchers and engineers have since expanded on these two printing techniques, which will be discussed further in the following section.
Construction methods
A number of different approaches have been demonstrated to date, which include on-site and off-site fabrication of building elements or entire buildings, using industrial robots, gantry systems, and tethered autonomous vehicles (see section on 3D Printers). Demonstrations of construction 3D printing technologies have included fabrication of housing, building elements (cladding, structural panels, and columns), bridges, civil infrastructure, artificial reefs, follies, and sculptures. Three different construction methods are currently used in 3D concrete printing: binder jetting, robotic shotcrete, and layered material extrusion.
Binder jetting
Binder jet 3D printing, also known as powder bed and binder 3D printing, was originally developed at the Massachusetts Institute of Technology for activating starch or gypsum powder with water as a binder, before Joseph Pegna applied the system to concrete. In binder jetting, a print head selectively deposits a liquid binder on a powdered substrate, layer by layer. The layer height typically varies between 0.2 and 2 mm and determines both the speed and the level of detail in the finished part. Post-processing steps are necessary in binder-jetting once the layered fabrication is complete. First, the unconsolidated powder needs to be removed mechanically, using brushes and vacuum tubes. Additional curing steps may also be necessary in ovens with controlled humidity and temperature or microwaves. Finally, coatings may also be applied on the surface to consolidate small surface features or to improve the surface quality of the part. Typical materials used for coatings are polyester or epoxy resin.
3D concrete printing with binder jetting technologies has been demonstrated at large scale by Enrico Dini with D-Shape. D-Shape relies on a non-hydraulic Sorel cement that is based on sand activated with magnesium oxide in the powder bed and a liquid magnesium chloride solution as binder. The technology has mainly been used to create furniture, such as a coffee table and the Root Chair designed by KOL/MAC LLC Architecture + Design in 2009. Furthermore, D-Shape produced large architectural parts, such as the 3 × 3 × 3 m Radiolaria pavilion designed by Shiro Studio in 2008, the Ferreri House for the Triennale di Milano in 2010, and a twelve-metre-long footbridge designed by Acciona in Madrid, in 2017.
Another exponent of binder-jet 3D concrete printing is California-based firm Emerging Objects. For their Bloom pavilion built in 2015, the company used an iron oxide-free cement and organic binder. While it is unclear if there is any cement hydration involved in the process, the project is often cited among other binder-jet 3D concrete printing projects due to the use of cement in the powder bed. Unlike the structures of D-Shape, which were fabricated in one piece, Emerging Objects fabricated 840 small building blocks that were stacked to create the 3.6 × 3.6 × 2.7 m structure.
Advantages and limitations
Compared to other 3D printing methods for architectural applications, binder jetting allows for a higher degree of geometric freedom, including the possibility of creating unsupported cantilevers or overhangs and hollow parts. Unlike other 3D printing processes that require auxiliary support structures, binder jetting relies on the bed of unbonded powder to ensure continuous support for consecutive layers during fabrication.
Typically, in binder jet 3D printing, the leftover powder can be reused for future parts. However, the recyclability of the cement and aggregate powder is problematic due to the exposure to ambient humidity, which can trigger the hydration process. Therefore, binder jet 3D printing is not suitable for on-site construction.
Layered extrusion 3D printing
Concrete layered extrusion 3D printing involves a numerically controlled nozzle that precisely extrudes a cementitious paste layer by layer. Layers are generally between 5 mm and a few centimeters in thickness. The extrusion nozzle may be accompanied by an automatic troweling tool that flattens the 3D-printed layers and covers the grooves at the interlayer interfaces, resulting in a smooth concrete surface. Additional automation steps have been proposed for the integration in one fabrication step of modular steel reinforcement bars or integrated building services, such as plumbing or electrical conduits. For this process, process planning and deposition speed are critical parameters that influence the material's stiffening and hardening rate.
Layered extrusion 3D concrete printing is most commonly used in on-site construction and is accompanied by large-scale 3D printers (see section on 3D Printers). The technology has seen a growing interest recently, with numerous universities, start-ups, and prominent established construction companies developing dedicated hardware, concrete mixes, and automation setups for concrete extrusion 3D printing. Applications include bridges, columns, walls, floor slabs, street furniture, water tanks, and entire buildings, both in prefabrication or on-site setups.
Advantages and limitations
Unlike conventional concrete casting and spraying, layered extrusion 3D printing needs no formworks. This is a significant advantage considering the fact that formworks in concrete construction can account for 50-80% of the resources, more than raw materials, reinforcement, and labour combined. The main challenges of layered concrete extrusion are the set on demand rheology of concrete, the integration of reinforcement, and the formation of cold joints at the interface between consecutive layers.
Slip forming
Robotic slip-forming, a process developed at ETH Zürich under the name Smart Dynamic Casting, is sometimes included in the family of concrete 3D printing processes, together with layered extrusion and binder-jetting. The process loosely fits the definition of 3D printing, due to its additive nature, with material being slowly extruded through an actuated mould that can vary its section. However, unlike the other 3D printing processes, slip forming is a continuous process, and not discrete or layer-based, and therefore it is more closely related to formative processes such as casting and extrusion.
Technology
3D printers for concrete
There are a few main categories of robots that are used for 3D concrete printing, which depend on the application, scale of the project, and printing technique. All construction 3D printers generally consist of a support structure and a printer head with a nozzle that extrudes the concrete. Printers are usually used in tandem with modelling software that uploads the building plans directly to the printer.
Gantry robots: Gantry robots are the most common in 3D concrete printing, and consist of a mobile gantry system with mixing and deposition systems. They can range from small lab models to large-scale printers for printing full components or structures. These printers are typically limited to vertical extrusions but have the benefit of high stability and easy scalability for larger projects. Gantry robots must be larger than the assembled structure, which can add cost to transportation and set-up costs. However, they are the easiest to control of all 3D printers.
Cable-driven system: In a cable-driven system, the print head is suspended between several fixed points within a frame. It has more geometric freedom than a gantry system and is more lightweight and transportable. However, it requires a wide area for equipment and planning is essential so that the cables do not overlap with the printed structure.
Robotic arm: This is similar to the robotic arms seen in assembly lines, which have six-axis movement and the most freedom of 3D printing systems. These are also capable of depositing concrete, embedding components like rebar, and performing any post-processing that may be required after the concrete sets. Robotic arms are the most compact system but are most commonly used for small-scale applications. However, large scale robotic arms based on heady duty construction equipment are now available, combining the print size of large gantry systems and the transportability of any standard construction equipment.
Printer parameters
In addition to printer type, specific printer parameters significantly impact the final performance of 3D printed concrete and must be carefully selected when planning for 3D printing construction. These parameters can simply be broken down into print head design and print speed.
Print head design
The print head must be selected so that the concrete mix can smoothly pass through the nozzle and create the bonding effect between each layer, while also initiating the solidification process. Similar to printer selection, nozzle shapes and sizes vary depending on the application. 3D printed concrete samples from nozzles with rectangular holes typically have higher strength than those printed with circular nozzles, because there are fewer gaps between each printed layer. However, circular nozzles are more adept for printing complex geometries. For samples printed from the same nozzle type, mechanical properties are improved when a larger nozzle is used.
The height of the print head is the height of the nozzle relative to the printing platform. This parameter affects the surface quality between layers including bond strength, and must be precisely adjusted. A print head that is set too high will reduce the bond strength between layers, causing an unstable shape. A nozzle too close to the printing surface may interfere with the printing process and place additional loads on the concrete. Research proposes a print height equal to the width of the nozzle.
Print speed
The speed at which the print head is set also influences the bonding strength. Increasing the nozzle speed generally decreases the adhesive strength, as the concrete has little time to set into place. However, taking too long to print successive layers reduces interlayer bonding, so a balance must be established that accounts for strength without premature collapse. Other factors that influence the quality of 3D printed concrete include the pumps and controls used to monitor the printer, as well as the concrete mix design (See section on Mix Design).
3D printer suppliers
3D concrete printing technology has grown exponentially over the last decade and is expected to continue to grow as researchers learn more about the software, hardware, and construction capabilities of these printers. Below are some notable companies and 3D printers that are used globally:
Mix design
Critical mix properties
For 3D printed concrete, buildability and extrudability are two of the most critical design properties for a mix. Extrudability is the mixture's ability to pass through nozzles in the printing head, while buildability is the capacity to support additional layers. These properties are governed by the consistency, cohesiveness, and stability of the mixture, which stem from the mix design and selected materials. For both properties, a balance must be met between stiffness and workability. A stiff mix will increase strength, but decrease flow rate and print speed, potentially clogging the printer head. Conversely, decreasing the stiffness too much may increase workability and extrudability at the expense of strength and buildability.
Since concrete is printed in layers, layers must sufficiently bond to each other to allow for proper curing and full-strength capacity. Significant research has been conducted to create an optimal mix for 3D printing, although there are no current industry standards. However, the use of supplementary cementitious materials (SCMs) such as metakaolin, fly ash, silica fume, and superplasticizers are common in all 3D printed concrete mixtures (See section on Admixtures).
Cementitious materials
Cementitious materials are integral to any concrete mix design. These materials serve as the binder that holds the mix together, as they chemically react with water to undergo the curing process. Portland cement is the most common material in construction for both 3D printed and traditional concrete applications due to its low cost and widespread availability. However, it's high setting time and low bonding ability are disadvantageous for 3D printed applications. Therefore, polymers and other admixtures are often added to reduce shrinkage and improve adhesion. Some of these polymers include rubber, mixed sand aggregates, carbon-sulfur polymers, and geopolymers, which also have added benefits of crack repair and resistance.
One alternative is sulfoaluminate cement which can be mixed with Portland Cement to quicken the hydration process and help develop early concrete strength after placement. While the setting time of Portland Cement is about half an hour, the setting time for sulfoaluminate cement is just six minutes. Therefore, higher strength can be achieved in a much shorter time period, increasing buildability.
Aggregates
Aggregate content and selection are just as important as the selected cementitious materials when it comes to concrete mix design. In particular, particle size has a significant effect on 3D-printed concrete mixes. Particle sizes that are too large may block the nozzle of the 3D printer, while aggregates that are too small decrease the strength of the mix and can cause cracking. A rule of thumb for mix design is that the maximum aggregate particle size should be less than 1/10 of the nozzle diameter to ensure smooth extrusion.
Several studies have been conducted to examine the influence of aggregate size on mechanical properties for 3D printed concrete. It was found that increasing coarse aggregate improves the volumetric stability of concrete and decreases hydration heat and shrinkage, which were common problems in early 3D-printed concrete mixes. The use of coarse aggregate also increases the concrete deposition rate and printhead speed, which can increase printing efficiency and productivity. Therefore, the printed structure achieves greater stability and strength, as observed by Ivanova and Mechtcherine. There is a limit to coarse aggregate content and size, as the challenge of controlling rheology becomes apparent. Natural aggregates such as sand and gravel are preferred as they require less energy to produce compared to artificial aggregates, but aggregate selection can be limited by regional deposits.
Admixtures
Admixtures include any materials outside of water, aggregates, and cementitious materials, that affect the concrete mix properties. Especially in 3D printed concrete, these admixtures are critical to balancing buildability, workability, and extrudability. Fly ash is the main admixture for high-performance 3D printed concrete, as it improves working performance and durability. However, large amounts of fly ash can lead to slower development of strength and buildability, which is why it is often mixed with other admixtures like clay, to retain shape stability.
Silica fume is another common admixture for 3D printed concrete mixes, as it increases the initial strength of printed concrete as well as flexural strength once the concrete cures. The main advantage of silica fume is that its small particles fill in the void spaces around the larger aggregates, which improves bonding performance with the cement binder. This also helps optimize the particle size distribution of the mix, which increases yield stress and buildability.
Mechanical properties
As with standard concrete mixes, mixes for 3D printed concrete are typically tested for their compressive and flexural strength. These mechanical properties are highly dependent on the mix design and can be improved by adding admixtures such as the ones described in the above section. For a mix containing ordinary Portland Cement, fly ash, silica fume, and fine glass aggregates, the compressive strength is around 36 to 57 MPa, which is comparable to the compressive strength of normal-weight concrete. High-performance concrete strengths of over 100 MPa have also been achieved by using superplasticizers and additional chemicals, but these mixes are more energy-intensive to produce.
For 3D printed concrete, the structural properties are largely influenced by the interlayer bonding performance. Increasing the print speed and printhead height can reduce the interlayer bond strength while adding a mortar between the layers can improve this strength. In particular, a resin mortar composed of black charcoal, sulfur, and sand has been found to be effective.
Concrete suppliers for 3D printing
Since there are no standards set for 3D printing concrete mix design, companies often pursue their own research and development if they decide to offer 3D printing as a construction service. Below are some notable companies that have successfully implemented 3D concrete printing into their scope of services.
Notable projects and applications
Due to challenges of reinforcement and limitations in printing technology, applications of 3D printed concrete have been mostly limited to small-scale projects, including models and residential homes, as opposed to large commercial buildings. There are, however, some notable projects around the world that demonstrate the potential of 3D-printed concrete.
Constructions-3D: La Citadelle des savoir-faire
La Citadelle Des Savoir-Faire is a project that employs 3D concrete printing to construct complex architectural structures. Located in France, this initiative aims to demonstrate the capabilities of 3D printing technology in sustainable construction. The Citadelle serves as an educational center where professionals and students can learn about and experiment with this technology. The project focuses on using eco-friendly materials and advanced design techniques, contributing to the reduction of the construction sector's carbon footprint. Once completed, this complex will have a total internal floor space of about 2565 square meters (27 600 sq ft).
A notable achievement of La Citadelle Des Savoir-Faire is the construction of the world's tallest 3D-printed building, La Tour. Built in 2023, this three-story building has set a new world record for its height at 14.14m (46.4 ft), illustrating the potential of 3D printing technology in creating large-scale structures
ICON: 3D-printed homes
ICON is creating a community of 100 3D-printed homes in Georgetown, Texas. Reservations will begin in 2023 with starting prices in the mid $400,000. The fleet of Vulcan printers can produce eight different floor plans of 3 to 4 bedrooms and 2 to 3 baths. A concrete feeding system known as Magma supplies the Vulcan printer with Icon's developed concrete mix known as Lavacrete, which can adjust for site weather conditions and supply read-to-print concrete automatically. The 90 to 200m2 3D printed homes take around five to seven days to print, compared to a timber frame which would take up to 16 weeks in the same area.
ICON also completed a project in March 2020 for seven 3D-printed homes in Austin, Texas. Each 400 ft2 home was printed in just 27 hours using ICON's Vulcan printer. The first residents moved into the homes in 2020 and are estimated to house 480 of the city's homeless, about 40% of the city's homeless population.
Habitat for Humanity: Affordable Homes Fast
In 2021, Habitat for Humanity, the world's largest non-profit home builder organization, built two 3D-printed homes in Williamsburg, Virginia, and Tempe, Arizona. The Virginia home was 1,200 ft2 and printed in just 28 hours with a COBOD 3D printer, which was about four weeks faster than standard construction. The organization estimated that the 3D-printed concrete walls saved about 15% per square foot in building costs. The 1,738 ft2 home in Arizona was constructed in the summer: a time when construction typically halts due to the extreme heat. 80% of the home was constructed using 3D printing including the interior and exterior walls, while the remainder, such as the roof, was constructed using traditional methods. Habitat for Humanity hopes that 3D printed homes can be a solution for affordable housing as well as labor shortages in extreme climates and environments.
PERI: Project Milestone
The first 3D-printed residential building in Germany was constructed in September 2020 by PERI, using COBOD's BOD2 printer and Heidelberg Cement's concrete mixture. 24 concrete elements were printed at a facility and then transported to the site for assembly. The printer created 1 m2 of wall every 5 minutes, completing the 160m2 home by November 2020. Only two operators were required to print the walls, which included water placement, electricity, and pipe connections.
Nijmegen, Netherlands: pedestrian bridge
In 2021, the Dutch city of Nijmegen revealed the world's longest 3D-printed concrete pedestrian bridge, spanning 29 meters. It was estimated that 3D printed saved about 50% in materials because concrete was only placed where structural strength was required. 3D-printed bridge components were manufactured by BAM and Weber Beamix offsite, where it was then transported and assembled on-site. The previous record holder for the longest 3D-printed concrete bridge was 26 meters, constructed by Tsinghua University in Shanghai.
Economic impacts
In terms of cost and economics, one advantage of 3D printed concrete is that it does not require formwork, which is used to form the mold for conventional concrete pouring. Formwork can account for up to 50% of total concrete construction due to material and labor costs. However, there are costs associated with machinery including the print head nozzles and supplemental monitoring devices. In addition, 3D printed concrete mixtures often differ from conventional concrete with additions of nano-clay, nano-silica, and other chemical admixtures that aid the extrusion process.
There are indirect economic benefits from 3D-printed concrete in terms of productivity. The construction sector is often highly traditional and for the most part, processes have remained similar over the past decades. This is in large part because current processes are still effective in many construction applications. For example, a study by Garcia de Soto compared a robotically fabricated and conventionally constructed wall assembly with different degrees of complexity and found that conventional construction outperformed robotic fabrication for simpler walls, while the robot was more productive as geometric complexity increased. There was no additional cost due to robotic fabrication and for both cases, material production was the driving factor for cost, as opposed to construction procedures.
Environmental impact
The environmental impact of 3D-printed concrete is heavily dependent on the processes and materials used for a given project. 3D printed concrete has the potential to reduce material in the production of concrete due to the elimination of formwork, but the specialized admixtures and required technology may have just as much of an impact on the environment as conventional concrete construction. A cradle-to-grave life-cycle assessment (LCA) comparing the environmental impact of a conventionally constructed concrete wall with a 3D-printed concrete wall revealed that the 3D-printed alternative only reduced environmental effects when no reinforcement was used. The LCA impacts of global warming potential, acidification potential, eutrophication potential, and smog formation potential were used to measure environmental impacts. Once reinforcement was introduced to the 3D-printed concrete structure, these impacts were greater than conventional construction methods, specifically for global warming and smog formation potential.
Another LCA conducted a similar study comparing conventional and 3D-printed concrete walls but varied the complexity of the structure. It was found that as the complexity of the structure increased, the 3D printed method how a lower environmental impact. This was mostly due to the ability of 3D-printed concrete to achieve complex forms while saving building materials in terms of formwork and concrete volume. Overall, the environmental impact of 3D-printed concrete is influenced by the structure's design and how well the engineer can optimize material usage. On a material basis, the environmental impacts are similar to that of conventional concrete, as a cement binder is still required. However, the streamlined construction process that comes with 3D printing decreases material waste and onsite emissions.
Based on four examples, it has been estimated that the contribution of greenhouse gas emissions per square meter associated with the construction of 3D-printed houses is lower than that of conventionally built ones.
Challenges and limitations
Several limitations prevent 3D concrete printing from being widely adopted throughout the construction industry. First, the material palette that can be used for 3D printed concrete is limited, particularly due to nozzle extrusion and the deposition process of concrete layers, which introduces the challenge of premature collapsing. Therefore, research on material properties and developing high-quality cementitious materials that comply with both structural concrete codes and 3D printing applications is a current area of focus. Due to the sensitivity of a concrete mix, a change in cement type, aggregate, or admixture will impact concrete properties and behavior.
Current building codes consider concrete as a homogenous material when in reality, concrete is anisotropic. This anisotropy is further exposed with printed layers, so new methods for estimating deformations and cracking must be developed. In addition, current material testing for concrete consists of cylindrical specimens in accordance with ASTM C39. There is currently no systematic or theoretical basis for 3D printed concrete, especially when it comes to standard testing.
Current 3D printed projects have been limited to model prototyping and low-rise, large-area buildings as opposed to high-rise commercial buildings because of restrictions in 3D printer technology. Printers need to be compatible with the height of the building, so additional research in 3D printer stability and design is required. There are also challenges with reinforcement in 3D concrete printing, which is required for taller structures. See reinforcement for 3D concrete printing for more details.
Research and development
Pioneering research on the topic of 3D concrete printing is conducted at the ETH Zurich, Loughborough University, Swinburne University of Technology, Eindhoven University of Technology, and the Institute for Advanced Architecture of Catalonia, among many other institutions.
Conferences
Due to the increased interest in 3D concrete printing both from industry and academia, a number of conferences have started internationally. Two industry-focused international conferences were organized in February and November 2017 by 3DPrinthused in Copenhagen. Subsequently, the biannual Digital Concrete academic conference was organized at the ETH Zürich in 2018, the Eindhoven Institute of Technology in 2020, and at the University of Loughborough in 2022. A parallel series of recurring conferences, focusing on the Asia-Pacific region, was organized at the Swinburne University of Technology in 2018, Tianjin University in 2019, and Shanghai Tongji and Hebei Universities in 2020.
Related topics
Concrete printing can be used directly to produce the final part, or indirectly, to produce formwork in which concrete is cast or sprayed.
3D-printed formworks address some of the major challenges of 3D concrete printing. Reinforcement bars can be integrated conventionally, and the conventionally cast or sprayed concrete complies with building codes. Additionally, the surface quality of concrete is significantly better than in 3D concrete printing. To achieve a smooth surface, the 3D-printed formworks can be coated or polished.
3D-printed concrete as formwork
3D concrete printing with layered extrusion has been used to produce stay-in-place formworks for casting concrete. In this approach, a thin shell, consisting of one or two 3D-printed contours is produced in a first step, either in a prefabrication plant or directly in situ. Subsequently, reinforcement cages are installed and secured in position. Finally, concrete is cast inside the shell, either in one go or in several steps to prevent the build-up of hydrostatic pressure in the lower sections of the formwork.
For structural calculations, the 3D-printed shell is usually ignored, and only the cast concrete is considered load-bearing. However, the 3D-printed shell may be considered for the necessary concrete reinforcement cover that protects the steel from corrosion.
3D-printed formworks for concrete
Alternatively, 3D printing with non-cementitious materials can be employed for the production of formworks for concrete. Extrusion printing with clay, foam, wax, and polymers, as well as binder jetting with sand and stereolithography, have been used for the fabrication of formworks for architectural concrete components.
See also
Construction 3D printing
Reinforcement in concrete 3D printing
3D printing
3D printing processes
Applications of 3D printing
Residential construction
Slip forming
Contour crafting
References
3D printing
Building technology
Concrete
Building engineering | 3D concrete printing | [
"Engineering"
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"Structural engineering",
"Building engineering",
"Civil engineering",
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69,633,464 | https://en.wikipedia.org/wiki/List%20of%20animals%20with%20humps | This is a list of animals that have a naturally occurring hump or humps as a part of their anatomy.
Humps may evolve, as a store of fat, as a heat control mechanism, as a development of muscular strength, as a form of display to other animals, or be apparent as a consequence of some behaviour such as the diving of whales. Enlarged humps have also been selected for by some animal breeders for aesthetic or religious reasons.
Dromedary - also known as Arabian camel, is a large even-toed ungulate, of the genus Camelus, with one hump on its back. The hump stores up to 80 lb (36 kg) of fat, which the camel can break down into energy to meet its needs when resources are scarce; the hump also helps dissipate body heat.
Bactrian camel - also known as the Mongolian camel or domestic Bactrian camel, is a large even-toed ungulate native to the steppes of Central Asia. It has two humps on its back, in contrast to the single-humped dromedary camel. Like the dromedary it can break down fat in its humps into energy to meet its needs when resources are scarce; and use them to help dissipate body heat.
Wild Bactrian camel - Once thought to have originated from escaped domesticated Bactrian camels, genetic studies have established it as a separate species which diverged from the Bactrian camel about 1.1 million years ago. A critically endangered species living in parts of northwestern China and southwestern Mongolia.
American bison - commonly known as the American buffalo or simply buffalo. Has a noticeable hump between its shoulder blades which unlike the camel is formed from muscle. The muscles assist in the shovelling of snow in winter allowing access to food.
Moose - or elk (in Eurasia) is the largest and heaviest extant species in the deer family. Like the bison it has evolved large muscles on top of its neck to help it shovel snow to find winter feed.
White rhinoceros - This species of rhino has a bulge on the back of its neck made of thickened skin, a pad of fat, thick muscle and ligament that support the animal's massive head.
Zebu - sometimes known by the collective nouns indicine cattle or humped cattle, is a species or subspecies of domestic cattle. The hump is composed of fat and gives the animal resilience to droughts, and helps it cool in extreme heat. The hump may have been exaggerated in size by selective breeding since domestication.
The eland, the largest of the antelope family. Its genus has two species in Africa, the common eland of East and Southern Africa and the giant eland of Central and Western Africa. Both have a slight hump above the forelegs which occurs by the anatomy of its spinal column and is not a true hump.
The hartebeest, a species of African grassland antelope, of which there are eight subspecies, all have a visible hump at the shoulder caused by the anatomy of the spine. The hump is due to the long dorsal processes of the vertebrae in the shoulder region.
Humpback whale - A species of baleen whale. Humpbacks can easily be identified by their stocky body, and obvious hump when diving. Humpbacks do not normally have a hump on their backs; the name comes from the large hump that forms when they arch their backs before making a dive.
The woolly mammoth, an extinct relative of the elephant that was adapted to cold Arctic environments, had a brown-fat hump like deposit behind its neck that may have functioned as a heat source and fat reservoir during winter.
Several species of waterfowl have a protuberance known as the basal knob at the top rear end of their bill. Examples are the knob-billed duck, the swan, and the Chinese goose. The exact purpose of basal knobs is unknown but they may serve as an indicator of health or sexual maturity.
A wide variety of birds have a casque, an enlargement of the bones of the upper mandible or the skull, either on the front of the face, or the top of the head, or both. Most hornbills and all cassowaries have a casque.
Concavenator was an extinct genus of theropod dinosaur that lived approximately 130 million years ago during the early Cretaceous period. Two extremely tall vertebrae in front of the hips formed a tall but narrow and pointed crest (possibly supporting a hump) on the dinosaur's back. It may have been a fat store, a display, or a thermal regulator.
Other dinosaurs with humps were Spinosaurus, Morelladon, and Deinocheirus mirificus.
Humphead wrasse (Cheilinus undulatus) is a species of bony fish, the largest species of wrasse mainly found on coral reefs in the Indo-Pacific region. It has a prominent hump on top of its head. It is believed the hump is a signal to females how genetically healthy a male is in a similar to a lion's mane or a buck's antlers.
Other fish which have developed a hump on the top of their heads are various large-bodied cichlids such as the peacock bass, Midas cichlid, and the starry-night cichlid, the humphead glassfish, and the hump-headed blenny. The flowerhorn cichlid is a hybrid aquarium fish bred for an extremely bulbous hump.
References
Humped
Morphology (biology) | List of animals with humps | [
"Biology"
] | 1,158 | [
"Lists of biota",
"Lists of animals",
"Animals",
"Morphology (biology)"
] |
69,633,577 | https://en.wikipedia.org/wiki/Crown%20distillery | A crown distillery () was one of the state-operated distilleries in Sweden between 1775 and 1824.
Establishment
The network of crown distilleries was established in 1775, when King Gustav III, acting on the advice of his finance minister , declared a state monopoly over the production and sale of alcoholic spirits, with the twofold goal of raising extra revenues for the state while also reducing alcohol consumption and its accompanying health and social problems. It therefore became illegal to obtain spirits by any means other than from the new Crown Distilleries, and as such the importation of spirits from abroad was banned, as was the distillation of spirits by private individuals.
Distilleries
Some 50-60 Crown Distilleries were established across the kingdom, including the following:
, Södermalm (Stockholm)
Strömsbro Crown Distillery, Gävle
, Södermalm (Stockholm)
Closure
The state monopoly was hugely unpopular, especially among the common people, as it banned the longstanding Swedish tradition of (roughly translatable as 'distillation for household needs'), though many people flouted the restrictions and continued to distil spirits illegally (). Moreover, the Crown Distilleries themselves failed to turn a profit. Gustav III was therefore forced to lift the monopoly at the of the Riksdag (the Swedish parliament), and most of the Crown Distilleries were shut down over the next couple of years. However, a few of the more profitable ones remained in operation for some time thereafter, and the last did not close until as late as 1824.
See also
Gustav III of Sweden
Systembolaget
References
Industrial history of Sweden
Alcohol monopolies
18th century in Sweden
Alcohol in Sweden
Distilleries
Alcohol law | Crown distillery | [
"Chemistry"
] | 361 | [
"Distilleries",
"Distillation"
] |
69,633,801 | https://en.wikipedia.org/wiki/Green%20train%20corridor | Green train corridor describes a concept where train coach toilet waste is no longer disposed directly on tracks. The trains instead feature built-in technology so that toilet waste is stored in a tank under every coach toilet, and is discharged into large drainage canals built along the line beside the tracks in main halting junctions.
Announcement and inauguration
On 24 July 2016, railway minister Suresh Prabhu announced India's First Green Rail Corridor on Manamadurai - Rameswaram line for the first time in ''Southern Railways Madurai Division.
See also
Passenger train toilet
Swachh Bharat Mission
Water supply and sanitation in India
References
Indian Railways
Passenger rail transport
Toilets | Green train corridor | [
"Biology"
] | 133 | [
"Excretion",
"Toilets"
] |
69,633,864 | https://en.wikipedia.org/wiki/Sea%20rewilding | Sea rewilding (also known as marine rewilding) is an area of environmental conservation activity which focuses on rewilding, restoring ocean life and returning seas to a more natural state. Sea rewilding projects operate around the world, working to repopulate a wide range of organisms, including giant clams, sharks, skates, sea sturgeons, and many other species. Rewilding marine and coastal ecosystems offer potential ways to mitigate climate change and sequester carbon. Sea rewilding projects are currently less common than those focusing on rewilding land, and seas are under increasing stress from the blue economy – commercial activities which further stress the marine environment. Rewilding projects held near coastal communities can economically benefit local businesses as well as individuals and communities a whole.
Overview
Sea rewilding aims to create conditions in which the various marine ecosystems are able to recover from prior damage and stressors and begin to thrive independently over time. Activities to facilitate this process can include species reintroduction and replenishing, i.e. of oysters, kelp, and seagrass beds. Sea rewilding aids in helping the climate crisis by capturing carbon dioxide, supports local economies with eco-tourism, reverse biodiversity loss, improve health and well being by providing restored natural landscapes, clean air, water, and healthy soil.
Seagrass
Seagrass meadows store carbon dioxide. More than 90% of the United Kingdom's historic seagrass meadows have been lost since the 1930s. Restoring meadows could offset carbon emissions and provide habitat for numerous fish and shellfish species. Research into seagrass, which covers about one percent of the sea floor suggests that it may be delivering 15–18% of carbon storage in the ocean. Meadows have been declining since the 1930s and are being lost at an alarming rate. Due to their scarcity they have been designated a UK habitat of principal importance. In the United States, a project at Chesapeake Bay is considered a success.
Native oysters
Oysters filter water, recycle nutrients and help to protect against coastal erosion. Oyster stocks have declined by 95 per cent in Europe due to over-harvesting, habitat loss, pollution and disease.
In Rhode Island, US, "wild oyster populations are at an all-time low", according to Eric Schneider, the principal marine biologist with the Rhode Island Department of Environmental Management's Division of Marine Fisheries. He also states: "oysters provide a number of essential ecosystem services, from water filtration to fish habitat and shoreline protection. By having oyster reef habitat absent from these systems, those services can be significantly depressed."
It has been demonstrated that restoring historic oyster beds improves water quality.
Kelp forests
Kelp forests are important habitats which have been lost over time in coastal waters. Kelp forests provide habitat for fish, protect coastlines from erosion and trap carbon dioxide from the ocean. They grow fast and absorb large amounts of carbon. Restoring kelp forests is a strategy to address climate change and enrich ocean livestock.
Marine protected areas
Marine protected areas are areas protected from certain activity. They are used to preserve and conserve areas where marine life has been disrupted or disturbed. Such disturbances could be overfishing, ocean pollution, and other similar disturbances.
In Chile, environmental groups such as Rewilding Chile are campaigning to create new protected areas.
Carbon capture
Rewilding the sea has been described as "the new way to capture carbon".
Organisations
Seawilding, a Scottish charity work with communities
NatureScot
Rewilding Britain
See also
Rewilding
Salmon conservation
Blue carbon
Reef burials
Further reading
References
Environmental protection
Marine conservation
Climate action plans
Ecological restoration
Rewilding
Blue carbon
Natural resources
Aquatic ecology | Sea rewilding | [
"Chemistry",
"Engineering",
"Biology"
] | 747 | [
"Aquatic ecology",
"Ecosystems",
"Ecological restoration",
"Environmental engineering"
] |
69,634,022 | https://en.wikipedia.org/wiki/Ice%20rinks%20in%20Hong%20Kong | Owing to the territory's subtropical climate, there are no natural winter sports venues in Hong Kong. Several artificial ice rinks have been constructed since the late 20th century, mainly inside shopping centres.
A video on ice rinks in Hong Kong in 2024.
List of ice rinks in Hong Kong
Former Rinks
History
1972 - The First Ice Rink
In a subtropical city like Hong Kong, there is no ice and snow in winter. Ice skating was not available to the locals until the 1st artificial ice rink was built in Lai Chi Kwok Amusement Park or commonly called "Lai Yuen".
Note: A newspaper mentioned that there was an ice rink in a private club as early as 1940. As there is no other supporting that it was an artificial rink, it was included in this record.
1982 - The First Shopping Mall Ice Rink
Swire Properties opened the first-ever shopping mall ice rink in Cityplaza or commonly known as "Taikoo Shing". Although it was small rink, the ice rink got so popular that the rink was moved from Cityplaza Phase 1 to Cityplaza Phase 2, a much larger ice surface.
1990 to 1991 - Grow from 2 rinks to 5 rinks
Shopping Malls owner, seeing the successful story of Cityplaza Ice Palace, followed suits. 3 new ice rinks opens in 6 months time:
Hutchison Group opened Whampoa Super Ice in Whampoa Garden
New World Development opened Riviera Ice Chalet in Riviera Garden
Sun Hung Kai Properties opened Tsuen Wan Plaza Ice Rink in Tsuen Wan Plaza
1990 to 1994 Mr. John Wagner - Ice Rink Resources Limited - 3 new rinks
Mr. John Wagner was the shopping mall manager of Cityplaza. He brought the idea of shopping mall ice rink to Hong Kong. After he retired from Swire Properties, he founded Ice Rink Resources Limited - an ice rink building and management company.
His company not only build and manage Riviera Ice Chalet, but further involved in building/managing 3 more ice rinks in Hong Kong and the 1st ice rink in Macau:
Sino Group opened Crystal Palace in Tuen Mun Town Plaza (1992). The rink was converted from car park spaces and had a low ceiling and 2 columns on the ice.
Future Bright Group opened Future Bright Ice Rink in Future Bright Amusement Park (1992)
Aberdeen Club opened Aberdeen Marina Club Ice Rink in Aberdeen Marina Club (1993)
ETON Properties opened Sky Rink in Dragon Centre (1994). The rink was built on a site that was originally designed for a cinema, public area was very limited.
Ice Rink Resources Limited's successor Ice Rink Management Asia Limited was formed in 1994 and kept on opening ice rinks around Asia.
1994 to 1997 3 ice rinks closed down
1994 Closure of Crystal Palace
1994 Crystal Palace closed down 1 year after Ice Rink Resources Limited, due to payment issues, withdraw from management. The site was changed to a shooting range.
??? Closure of Tsuen Wan Plaza Ice Rink
Unexpectedly, Tsuen Wan Plaza closed down and the site was rented to Jumpin Gym U.S.A.
1996-1997 Opening and closure of Yuen Long Plaza Ice Rink
It was said that Sun Hung Kai Properties moved some of the equipment of Tsuen Wan Plaza and opened another rink in Yuen Long Plaza. However, the rink was closed in about 1 year time.
1997 Closure of Whampoa Super Ice
Though the business is good in Whampoa Super Ice, the landlord did not extend the lease with the rink in 1997. The site was again rented to Jumpin Gym U.S.A.
1997 Asian Financial Crisis
The 1997 Asian financial crisis put a halt to the growth of ice rinks in Hong Kong. For nearly 10 years, no new ice rink was built. No new ice rink was built around Asia for at least 5 years.
1998 Festival Walk Glacier became the largest ice rink in Hong Kong
Ted Wilson, manager of Cityplaza Ice Palace, first proposed to Swire Properties for a second ice rink in 1992. After more than 6 years of planning, Swire Properties finally opened its second ice rink, Festival Walk Glacier, in Kowloon Tong. Festival Walk Glacier became the largest ice rink in Hong Kong.
The project was delayed due to unexpected construction complications.
2007-2008 Ice Hockey and the First Standard Size Ice Rink
Two new ice rinks, both promoting ice hockey, opened. One of them is the first standard-size ice rink in Hong Kong:
Chickeeduck's owner Hubert Chow, formed The Rink and opened The Rink Elements
Kerry Properties opened Mega Ice in MegaBox - the first standard size ice rink in Hong Kong
2021 Openings of 2 More Standard Size Ice Rinks
Hong Kong Resort Company Limited opened DB Ice Rink in Discovery Bay
LOHAS Rink in The LOHAS
References
Ice rinks by country
Ice rinks
Ice rinks | Ice rinks in Hong Kong | [
"Engineering"
] | 992 | [
"Structural engineering",
"Ice rinks"
] |
69,634,673 | https://en.wikipedia.org/wiki/Laurie%20Marhoefer | Laurie Marhoefer is a historian of queer and trans politics who is employed as the Jon Bridgman Endowed Professor of History at the University of Washington. In January 2021, together with Jennifer V. Evans, they facilitated the Jack and Anita Hess Research Seminar at the United States Holocaust Memorial Museum on LGBTQ+ histories of the Holocaust.
Works
References
Living people
University of Washington faculty
Historians of Germany
Historians of sexuality
Year of birth missing (living people)
Historians of LGBTQ topics
LGBTQ studies academics | Laurie Marhoefer | [
"Biology"
] | 100 | [
"Behavior",
"Sexuality",
"Historians of sexuality"
] |
66,903,382 | https://en.wikipedia.org/wiki/Isha%20Datar | Isha Datar (born January 6, 1988) is the executive director of New Harvest, known for her work in cellular agriculture, the production of agricultural products from cell cultures.
Early life and education
Datar was raised in Edmonton, Alberta, Canada. Her mother worked at a dairy farm, where Datar spent much of her childhood growing vegetables alongside her. Datar's mother was also a sculptor, and her father a doctor. After an elementary school field trip to a landfill, she became invested in reducing global waste and the impact of climate change. She received a B.S. from the University of Alberta in 2009. During her time as an undergraduate, Datar took a meat science class that challenged her idealistic vision of the sustainability of the animal agriculture industry and introduced her to cellular agriculture. Datar received her M.Biotech from the University of Toronto Mississauga in 2013.
Career
In 2009, Datar published "Possibilities for an in-vitro meat production system" in Innovative Food Science and Emerging Technologies, which detailed the progress of cellular agriculture. The paper was sent to Jason Matheny – founder and then-director of New Harvest – who forwarded the paper to those who were mentioned in it. In 2013, Datar became the chief executive officer at New Harvest. Datar also co-founded Muufri (now Perfect Day) and Clara Foods (now The EVERY Company). In 2021, Robert Downey Jr. funded Datar's work through his 'fast grants' project. Datar has been profiled in media venues including USA Today, the magazine Toronto Life, the Calgary Herald. She has spoken with NPR's Science Friday, The New Republic, Food & Wine magazine, and the National Observer.
Awards and honors
Canadian Business spotlighted her work as a 2016 Change Agent. In 2019, Datar was named one of 25 Food and Agriculture Leaders to Watch by FoodTank.com.
Maclean's listed Isha Datar in its "The Power List: Top 10 Food Titans", where she is credited with coining the term cellular agriculture.
References
External links
, April 27, 2013
Isha Datar: How we could eat real meat without harming animals at TEDMonterey, July 2021
Living people
Canadian women in business
University of Toronto alumni
Canadian Biotechnologists
University of Alberta alumni
1988 births
Canadian people of Indian descent
Women biotechnologists | Isha Datar | [
"Biology"
] | 488 | [
"Biotechnologists",
"Women biotechnologists"
] |
66,904,553 | https://en.wikipedia.org/wiki/Cellular%20deconvolution | Cellular deconvolution (also referred to as cell type composition or cell proportion estimation) refers to computational techniques aiming at estimating the proportions of different cell types in samples collected from a tissue. For example, samples collected from the human brain are a mixture of various neuronal and glial cell types (e.g. microglia and astrocytes) in different proportions, where each cell type has a diverse gene expression profile. Since most high-throughput technologies use bulk samples and measure the aggregated levels of molecular information (e.g. expression levels of genes) for all cells in a sample, the measured values would be an aggregate of the values pertaining to the expression landscape of different cell types. Therefore, many downstream analyses such as differential gene expression might be confounded by the variations in cell type proportions when using the output of high-throughput technologies applied to bulk samples. The development of statistical methods to identify cell type proportions in large-scale bulk samples is an important step for better understanding of the relationship between cell type composition and diseases.
Cellular deconvolution algorithms have been applied to a variety of samples collected from saliva, buccal, cervical, PBMC, brain, kidney, and pancreatic cells, and many studies have shown that estimating and incorporating the proportions of cell types into various analyses improves the interpretability of high-throughput omics data and reduces the confounding effects of cellular heterogeneity, also known as tissue heterogeneity, in functional analysis of omics data.
Mathematical Formulation
Most cellular deconvolution algorithms consider an input data in a form of a matrix , which represents some molecular information (e.g. gene expression data or DNA methylation data) measured over a group of samples and marks (e.g. genes or CpG sites). The goal of the algorithm is to use these data and return an output matrix , representing the proportions of distinct cell types in each of the samples. Some methods limit the sum of each column of matrix less than or equal to one, so that the proportions of cell types sum up to the overall number of cells in the sample (less than one when there are some unknown cell types in the samples). Moreover, it is assumed that the values of matrix are non-negative as they pertain to proportions of cell types.
Current strategies
There are two broad categories of methods aiming at estimating the proportion of cell types in samples using some type of omics data (bulk gene expression or DNA methylation data). These approaches are labeled as reference-based (also called supervised) and reference-free (also called unsupervised) methods
Reference-based methods
Reference-based methods require an a priori defined reference matrix consisting of the expected value (also called profile or signature) of gene expression (or DNA methylation) for a group of genes (or CpG sites) known to have a differential expression (or methylation)
across the cell types. A reference matrix can be represented by a matrix , representing the expected value for markers (genes or CpG sites) for each of cell types known to be presented in the samples. These references can be derived by exploring external single-cell epigenomics or transcriptomics datasets generated for a group of samples similar (e.g. in terms of biological condition, sex and age) to the samples for which the deconvolution method will be applied. These methods use statistical approaches such as non-negative or constrained linear regression methods to dissect the contribution of each cell type to the aggregated bulk signals of genes or CpG sites. Constrained regression is the basis for many of reference-free cellular deconvolution methods existing in the literature, aiming at estimating the cell proportion values () that maximizes the similarity between and . The performance of reference-based methods depends critically on the quality of the reference profiles.
Construction of reference profiles
There are a variety of approaches for isolating different cell types to measure their gene expression or DNA methylation levels to be used as references in the deconvolution algorithms. Earlier methods used cell sorting methods such as FACS (fluorescence-activated cell sorting) based on the flow cytometry technique, which separates the populations of cells belonging to different cell types based on their cell sizes, morphologies (shape), and surface protein expressions. With the advance in single-cell technologies, newer approaches started to incorporate references for cell-types measured on a single-cell resolution obtained for a subset of subjects in the study or external subjects from a similar biological condition.
Reference-free methods
Reference-free methods do not need the reference profiles of cell-type specific genes (or CpGs), although they might still require the identity (name) of cell-type-specific genes (or CpGs). These methods might be considered as a modification of reference-based methods where both and are unknown, and the goal is to jointly estimate both matrices so that the similarity between and is maximized. Many of the reference-free methods are based on mathematical framework of non-negative matrix factorization, which imposes a non-negativity constraint on the elements of and . Additional constraints such as the assumption of orthogonality between the columns of might be incorporated to improve the interpretability of results and prevent overfitting.
Advantages and limitations
Advantages
In silico cell-type level resolution
The advance of single-cell technologies enables the profiling of each individual cell in a sample, which help elucidate the issue of cellular heterogeneity by measuring the proportions of different cells in samples. Even though the quality of single cell profiling technologies has been on the rise in recent years, these technologies are still costly, limiting their applications in large populations of samples. Single cell technologies such as single cell transcriptomic methods also tend to have higher error rates due to factors such as high dropout events. Cellular deconvolution methods provide a robust and cost-effective in silico alternatives for understanding the samples on a cell-type level resolution, by relying on single cell information of only a small subset of cells in the sample, the reference profiles generated by external sources, or even no reference profile at all.
(Re)analysis of old data
There are large amounts of old bulk data, such as microarray, from studies concerning various diseases and biological conditions. These datasets could be considered important resources in studying of rare disease, long follow-up studies or samples and tissues that are difficult to extract. In addition, this can also improve the statistical power by combining similar datasets. Since the biological samples for many of these studies are not available or accessible anymore, reprofiling the data using single cell technologies might not be within the realm of possibilities for many studies. Invention of more advanced cellular deconvolution methods gives the opportunity to researchers to come back to old omics studies, reanalyze their datasets, and scrutinize their findings.
Limitations
Reliability of reference
Reference-based approaches rely on the availability of accurate references to estimate cell proportions. The discrepancy between the biology of the samples underlying the references and the samples for which the cell proportions are being estimated could introduce bias in estimated cell proportions. Studies have shown that using references obtained from samples with different phenotypes such as age, gender, and disease status than the population of interest reduces the performance of reference-based methods to levels lower than their reference-free counterparts.
Lack of reference for rare, unknown, or uncharacterized cell types
Reference-based approaches assume the existence of prior knowledge on the types of cells existing in a sample. Therefore, these methods may fail to perform accurately when the data includes rare or otherwise unknown cell types with no references incorporated in the algorithm. For example, cancer tumors consist of heterogeneous mixtures of various healthy cells of different types such as immune cells and cells related to affected tissues in addition to tumor cells. Although it might be possible to provide references for the immune cells, we do not usually have access to references or signatures for cancer cells due to the unique patterns of mutations and distributions of molecular information in each individual. These situations have been addressed in some studies under the label of deconvolution methods with partial reference availability.
Applications
Relationship between cell proportions and phenotypes
Studies have shown that the proportions of different cell types might show correlations with various phenotypes such as different diseases. For example, the proportions of Parathyroid oxyphil cells in the samples collected from the parathyroid gland for groups of patients show a significant correlation with the presence of clinical characteristics of chronic kidney disease (CKD). Another study applying the cellular deconvolution algorithms to gene expression data of Alzheimer's patients find that patients with lower proportions of neuronal cells in the samples collected from their cerebral cortex are more likely to show the clinical characteristics of dementia. Cellular deconvolution algorithms could enable researchers to investigate the interactions between cell proportions and various diseases or biological phenotypes.
Dissecting the confounding effects of cell proportions in EWAS and TWAS studies
Epigenome-wide association study (EWAS) and transcriptome-wide association studies (TWAS) aim at finding the molecular markers such as genes or methylation CpG sites that show significant correlations between their expression or methylation levels and a biological phenotype of interest such as a disease. Since the proportions of cell types in samples vary and might show significant correlations with the disease or phenotype of interest, these correlations may confound the functional relationships between genes or CpG sites and the disease or phenotypes under study. For example, studies aimed at finding genes involved in Alzheimer's disease may end up selecting genes that are exclusively expressed in neurons and therefore have lower expression levels in Alzheimer's patients due to compositional changes of cell types during neurodegeneration. Such genes are not actionable targets for the treatment of Alzheimer's since they are not causally involved in the biological mechanism underlying Alzheimer's disease, but are only brought up by the confounding effects of cell types.
References
Developmental biology | Cellular deconvolution | [
"Biology"
] | 2,091 | [
"Behavior",
"Developmental biology",
"Reproduction"
] |
66,909,336 | https://en.wikipedia.org/wiki/Lanthanum%28III%29%20nitrate | Lanthanum(III) nitrate is any inorganic compound with the chemical formula . It is used in the extraction and purification of lanthanum from its ores.
The compound decomposes at 499°C to lanthanum oxide, nitric oxide and oxygen.
Preparation
Lanthanum nitrate is prepared by reacting lanthanum oxide with nitric acid which creates lanthanum(III) nitrate and water.
References
Lanthanum compounds
Nitrates | Lanthanum(III) nitrate | [
"Chemistry"
] | 93 | [
"Inorganic compounds",
"Oxidizing agents",
"Salts",
"Nitrates",
"Inorganic compound stubs"
] |
66,909,342 | https://en.wikipedia.org/wiki/Puttoo | Puttoo was the coarse woolen cloth used in and before the 19th century in the Indian subcontinent. It was made of camel's hair or yak.
Quality
Puttoo was a less expensive woolen material used by locals of hilly areas for their daily garments like shawls and chogas (long coats), often decorated with silk threads. Puttoo was softer than few contemporary varieties such as Sulung or Kerseymere. Although these woolen varieties were from the same animals, the difference was the wool's quality, maybe because it was classified or picked from specific body parts. Puttoo was a smaller width cloth, one piece (of 8-10 yards) was priced at Rupees three to seven only.
Use
Puttoo was used for various winter clothing types, but it was primarily used for cheaper shawls and long coats, also called chogas. Sometimes the products were decorated with silk braid and lacework.
See also
Wool
Thibet cloth
References
Woolen clothing
Wool
Camel products
Animal hair products | Puttoo | [
"Physics"
] | 212 | [
"Materials stubs",
"Materials",
"Matter"
] |
66,910,343 | https://en.wikipedia.org/wiki/Casimersen | Casimersen, sold under the brand name Amondys 45, is an antisense oligonucleotide medication used for the treatment of Duchenne muscular dystrophy (DMD) in people who have a confirmed mutation of the dystrophin gene that is amenable to exon 45 skipping. It is an antisense oligonucleotide of phosphorodiamidate morpholino oligomer (PMO). Duchenne muscular dystrophy is a rare disease that primarily affects boys. It is caused by low levels of a muscle protein called dystrophin. The lack of dystrophin causes progressive muscle weakness and premature death.
The most common side effects include upper respiratory tract infections, cough, fever, headache, joint pain and throat pain.
Casimersen was approved for medical use in the United States in February 2021, and it is the first FDA-approved targeted treatment for people who have a confirmed mutation of the DMD gene that is amenable to skipping exon 45.
Medical uses
Casimersen is indicated for the treatment of Duchenne muscular dystrophy (DMD) in people who have a confirmed mutation of the DMD gene that is amenable to exon 45 skipping.
Adverse effects
Common side effects include: headache, fever, joint pain, cough and cold symptoms.
Pharmacology
Pharmacodynamics
Duchenne muscular dystrophy is an X-linked recessive disorder that results in the absence of a functional dystrophin protein. Dystrophin protein is a protein that consists of an N-terminal actin-binding domain, C-terminal B-dystroglycan- binding domain, and 24 internal spectrum-like repeats. Dystrophin plays a role in muscle function and without dystrophin, muscle tissue will be replaced with fibrous and adipose tissue. Casimersen is an antisense phosphorodiamidate morpholino oligonucleotide designed to bind to the exon 45 of the DMD pre-MRNA, which prevents its exclusion into the mature RNA before translation. This change causes the production of an internally truncated dystrophin protein.
History
Casimersen was evaluated in a double-blind, placebo-controlled study in which 43 participants were randomized 2:1 to receive either intravenous casimersen or placebo. All participants were male, between 7 and 20 years of age, and had a genetically confirmed mutation of the DMD gene that is amenable to exon 45 skipping. The benefit was evaluated by measuring the level of dystrophin in muscle biopsies in 43 participants before treatment and at week 48, in an interim analysis. The trial was conducted at seven sites in five countries (United States, Canada, Germany, Spain, Czech Republic).
The U.S. Food and Drug Administration (FDA) granted the application for casimersen fast track, priority review, and orphan drug designations. The FDA granted the approval of Amondys 45 to Sarepta Therapeutics, Inc.
References
External links
Muscular dystrophy
Orphan drugs
Therapeutic gene modulation
Antisense RNA
Morpholines
Muscle protectors | Casimersen | [
"Biology"
] | 677 | [
"Therapeutic gene modulation"
] |
66,912,943 | https://en.wikipedia.org/wiki/Stefan%20Bon | Stefan A. F. Bon is a Professor of Chemical Engineering in the department of Chemistry at the University of Warwick, United Kingdom. His research considers polymer-based colloids. He is a Fellow of the International Union of Pure and Applied Chemistry, an elected member of the International Polymer Colloids Group (IPCG), and member of the physical Newton international fellowship committee, and served as the Royal Society of Chemistry Outreach Lecturer in 2015-2016.
Academic career
Bon studied chemical engineering at the Eindhoven University of Technology (TUe) in the Netherlands, obtaining his integrated undergraduate and MSc in Chemical Engineering (ir.) in 1993. He continued to specialize in the area of polymer and colloid science, with research in nitroxide-mediated reversible-deactivation radical polymerization (RDRP), and obtained his PhD in 1998 in polymer chemistry under the supervision of Anton L. German. He worked as a postdoctoral research assistant with David M. Haddleton at the University of Warwick from spring 1998, and was appointed as Unilever Lecturer in polymer chemistry in January 2001. He continues his career at the University of Warwick where he is a professor in polymer and colloid chemical engineering.
Research
Bon pioneered nitroxide-mediated reversible-deactiviation radical emulsion polymerization. His current research takes a chemical engineering and soft matter physics approach to sustainable polymer and colloidal systems. Research themes in the BonLab are: colloid and polymer science for the environment, a mechanistic understanding of polymer and colloid synthesis and physical/mechanical behaviour, out-of-equilibrium active matter, colloidal materials for a circular economy, and colloids at interfaces: adhesion and film formation. Bon has rich experience working with a great variety of industrial collaborators on projects with applications in coatings and adhesives, personal care products, agricultural formulations, and paper.
Alongside his academic research, Bon is chair of the Polymer Club, an industrial consortium aimed at promoting research and education in polymer and colloid science. He is the founder and host of the 2020 COVID19 international polymer colloids group webinar series. He is also a member of the physical Newton international fellowship committee.
Honours and awards
Elected Fellow of the International Union of Pure and Applied Chemistry
Royal Society of Chemistry Materials Division Outreach Lecturer (2015-2016)
Winner of a Warwick Award for Teaching Excellence [WATE] (2021).
Selected publications
Small molecule organic eutectics as candidates to replace plastics. Ryan, J., L.; Sosso, G., C.; and Bon, S., A., F. Chem. Sci. , 15: 14458-14470. 2024. DOI https://doi.org/10.1039/D4SC02574A
A mesh reinforced pressure-sensitive adhesive for a linerless label design. Brogden, E., M.; Wilson, P., F.; Hindmarsh, S.; Hands-Portman, I.; Unsworth, A.; Liarou, E.; and Bon, S., A., F. RSC Applied Polymers, 2: 248-261. 2024. DOI https://doi.org/10.1039/D3LP00224A
Samuel R. Wilson-Whitford, Ross W. Jaggers, Brooke W. Longbottom, Matt K. Donald, Guy J. Clarkson, and Stefan A. F. Bon (22 January 2021). "Textured Microcapsules through Crystallization". ACS Applied Materials and Interfaces. 13 (4): 5887-5894. doi:10.1021/acsami.0c22378
References
Chemical engineering academics
Eindhoven University of Technology alumni
21st-century Dutch scientists
Academics of the University of Warwick
British LGBTQ scientists
Year of birth missing (living people)
Living people | Stefan Bon | [
"Chemistry"
] | 814 | [
"Chemical engineering academics",
"Chemical engineers"
] |
66,914,990 | https://en.wikipedia.org/wiki/Sex%20as%20a%20biological%20variable | Sex as a biological variable (SABV) is a research policy recognizing sex as an important variable to consider when designing studies and assessing results. Research including SABV has strengthened the rigor and reproducibility of findings. Public research institutions including the European Commission, Canadian Institutes of Health Research, and the U.S. National Institutes of Health have instituted SABV policies. Editorial policies were established by various scientific journals recognizing the importance and requiring research to consider SABV.
Background
Public research institutions
In 1999, the Institute Of Medicine established a committee on understanding the biology of sex and gender differences. In 2001, they presented a report that sex is an important variable in designing studies and assessing results. The quality and generalizability of biomedical research depends on the consideration of key biological variables, such as sex. To improve the rigor and reproducibility of research findings, the European Commission, Canadian Institutes of Health Research, and the U.S. National Institutes of Health (NIH) established policies on sex as a biological variable (SABV). Enrolling both men and women in clinical trials can impact the application of results and permit the identification of factors that affect the course of disease and the outcome of treatment.
In 2003, the European Commission (EC) began influencing investigators to include sex and gender in their research methodologies. The Canadian Institutes of Health Research (CIHR) requires four approaches: sex and gender integration in research proposals, sex and gender expertise among research teams, sex and gender platform in large consortiums, and starting in September 2015, the completion of sex and gender online training programs.
In May 2014, the NIH announced the formation of SABV policy. The policy came into effect in 2015 which specified that "SABV is frequently ignored in animal study designs and analyses, leading to an incomplete understanding of potential sex-based differences in basic biological function, disease processes, and treatment response. NIH expects that sex as a biological variable will be factored into research designs, analyses, and reporting in vertebrate animal and human studies. Strong justification from the scientific literature, preliminary data or other relevant considerations must be provided for applications proposing to study only one sex." The review criteria should assess the extent to which the sex of participants has been incorporated into the research plan.
Scientific journals
In 2010, the National Centre for the Replacement, Refinement and Reduction of Animals in Research published the ARRIVE guidelines which promotes incorporating SABV in animal studies. In 2012, the American Physiological Society (APS) journals began requiring sex and gender to be reported in studies involving cells, tissues, animals, and humans. This APS editorial policy was not widely accepted by reviewers and researchers.
The European Association of Science Editors established the gender policy committee (GPC) in 2012. The GPC published Sex and Gender Equity in Research (SAGER) guidelines in 2016. In January 2017, the Journal of Neuroscience Research began requiring the consideration of SABV. The December 2017 ICMJE recommendations encouraged the use of SABV by researchers.
Impact
Research incorporating sex as a biological variable increases the rigor and reproducibility of results. After publishing the NIH published SABV policy, there were increases in the percentage of scientists understanding and recognizing its importance. Some investigators were critical of the NIH SABV policy, saying it would increase cost and labor requirements. Including SABV in basic research and preclinical studies can reduce costs and time requirements to test sex differences in clinical trials.
Historically, there were concerns among researchers of the female reproductive system impacting findings in animal studies. Other studies using mice models found that despite the estrous cycle, variability was the same among sexes. Studies following SABV policies can identify potential hormonal variability in earlier phases of biomedical research.
In 2020, the NIH Office on Women's Health and the Food and Drug Administration Office of Women's Health created an educational tool, Bench-to-Bedside: Integrating Sex and Gender to Improve Human Health.
References
biological variable
Medical research
Articles containing video clips
Sex differences in humans | Sex as a biological variable | [
"Biology"
] | 831 | [
"Sex"
] |
66,916,032 | https://en.wikipedia.org/wiki/Josef%20Gitelson | Josef (Joseph or Iosif) Isaevich Gitelson (; 6 July 1928 – 25 September 2022) was a Soviet and Russian biophysicist. PhD in biology (1955), DrSc in medicine (1961), Professor, Member of the Russian Academy of Sciences (1991); Corresponding member of the USSR Academy of Sciences (1979), Member of the USSR Academy of Sciences (1990). Director of Institute of Biophysics, Siberian Branch of the Russian Academy of Sciences (1984-1996). Academic Advisor at this Institute since 1996. Scientific supervisor of Institute of Fundamental Biology and Biotechnology Siberian Federal University. Member of International Academy of Astronautics. Honorary Citizen of Krasnoyarsk Krai since Sept 20, 2013 and the city of Krasnoyarsk. In 2018, JI Gitelson was awarded the highest award of the Russian Academy of Sciences, Lomonosov Gold Medal for the justification and development of the ecological direction of biophysics, which has achieved a number of outstanding fundamental and practical results, in particular, in marine and laboratory studies of bioluminescence.
Biography
Born in Samara on 6 July 1928. His father, Isai Isaakovich Gitelson (1896-1965), was a dermatologist, Doctor of Medical Sciences (1940), Professor at the Krasnoyarsk State Medical Institute (1945-1965) (now, the Krasnoyarsk State Medical University named after Professor Voino-Yasnetsky). The Krasnoyarsk State Medical University since 1966 has been annually awarded the prize for the best scientific student work from the personal foundation bequeathed by Professor Isai Isaakovich Gitelson.
In 1951 Josef Gitelson graduated from the Faculty of Biology of the Lomonosov Moscow State University.
In 1952 he graduated from the medical faculty of the Krasnoyarsk Medical Institute.
From 1952 to 1953, he was a haematologist at the Krasnoyarsk Blood Transfusion Station.
From 1953 to 1957 - assistant, associate professor at the Krasnoyarsk Agricultural Institute.
From 1957 to 1961 - Senior Researcher at the Biophysics Laboratory of the Institute of Physics of the Siberian Branch of the USSR Academy of Sciences, Krasnoyarsk.
From 1961 to 1981 - Head of the Laboratory of Photobiology of the Institute of Physics named after L. V. Kirensky, Siberian Branch of the USSR Academy of Sciences.
From 1981 to 1991 - Head of the laboratory of photobiology, and in 1984-1996 - director of the Institute of Biophysics, Siberian Branch of the USSR/Russian Academy of Sciences.
From 1996 - Academic Advisor at the Institute of Biophysics, Siberian Branch of the Russian Academy of Sciences.
Research achievements
1951 to 1970. In experimental hematology, JI Gitelson developed methods for the spectrophotometric analysis of red blood cell populations in normal and pathological conditions. He developed a general theory of the three-stage mechanism of hemolysis, described the patterns of distribution of red blood cell populations by stability, depending on their age, the intensity of production and destruction. He created mathematical models of erythropoiesis in normal conditions and in the case of blood loss.
1960 to 1985. Development of biophysical instruments and methods for instrumental research of large aquatic ecosystems. Design of a device for measuring the bioluminescence of marine ecosystems — a deep-sea bathyphotometer. Participation in a series of oceanographic expeditions in the Pacific, Atlantic, Indian and Arctic Oceans in the 1960s and 1980s, describing the main patterns of bioluminescence as a general oceanic phenomenon and its distribution in the World Ocean depending on the structure and productivity of marine ecosystems. The internationally renowned Russian bioluminescent research group was set up by Joseph Gitelson.
1961 to 1998. Development of biospherics-the section of ecology devoted to the study and creation of closed ecosystems. Development and creation of the complex "BIOS" - an experimental closed ecological system of human life support. Conducting long-term experiments in it. For the first time, the possibility of creating a stable, controlled, closed ecosystem for humans based on continuous cultivation of microorganisms and higher plants was experimentally demonstrated. The purpose of such systems is to support human life in space and in unfavourable conditions of the Earth: in the Arctic and Antarctic, under water, underground, in the high mountains, deserts, as well as in a polluted environment. According to the leaders of the project "Biosphere II", the most advanced work prior to their project "was conducted by Josef Gitelson and his team at the Bios-3 facility."
1995 to 1998. Development of the "Bioalarm" project aimed at monitoring the "health" of marine ecosystems and early warning of anomalies arising from anthropogenic and natural factors.
According to Encyclopedia of Krasnoyarsk Krai, J.I. Gitelson has initiated a number of scientific projects important for the future of humanity: "Ecology of Great Rivers of the World" (supported by UNESCO), "The Pristine Yenisey River " (supported by the Russian Academy of Sciences and Krasnoyarsk Territorial administration; "Chlorophyll in Biosphere").
Within the framework of "The Pristine Yenisey River" program, methods were developed for an objective assessment of the negative environmental consequences of hydroelectric power plants, the calculation of environmental compensation was justified, and options for constructive solutions were proposed that would help mitigate the harm caused.
References
External links
1928 births
2022 deaths
Scientists from Samara, Russia
Full Members of the Russian Academy of Sciences
Full Members of the USSR Academy of Sciences
Moscow State University alumni
Recipients of the Lomonosov Gold Medal
Recipients of the Order "For Merit to the Fatherland", 4th class
Recipients of the Order of Friendship of Peoples
Recipients of the Order of the Red Banner of Labour
Russian biophysicists
Soviet biophysicists
Russian Academy of Sciences
USSR Academy of Sciences | Josef Gitelson | [
"Technology"
] | 1,229 | [
"Science and technology awards",
"Recipients of the Lomonosov Gold Medal"
] |
66,916,343 | https://en.wikipedia.org/wiki/Cristina%20Nevado | Cristina Nevado (born 1977) is a Spanish chemist who is a Professor of Organic Chemistry at the University of Zurich. Her research considers chemical synthesis and organometallic reactions. She received the 2021 Margaret Faul Women in Chemistry Award.
Early life and education
Nevado was born in Madrid and grew up in Spain. She was the first scientist in her family. At high school she was inspired by her chemistry and physics teachers to pursue a career in science. She eventually studied chemistry at the Autonomous University of Madrid, and earned her bachelor's degree in 2000. During one summer holiday she worked at the Menéndez Pelayo International University, where she met international students and realised the scientific community was global. She remained at the Autonomous University for her doctoral research, where she worked on organic chemistry and the cyclisation of enynes that had been catalysed by gold and platinum complexes. After earning her doctorate, Nevado moved to the Max Planck Institute for Coal Research, where she worked as a postdoctoral fellow with Alois Fürstner. Her postdoctoral research considered natural product synthesis. She spent three months working alongside Eiichi Nakamura at the University of Tokyo.
Research and career
Nevado joined the University of Zurich as an Assistant Professor in 2007. Her research has concentrated on catalysis and the development of selective, sustainable approaches to develop new materials. In particular, Nevado is interested in new approaches to construct C–C and C–X bonds based on transition metal catalysts. In 2011 Nevado was awarded a Starting Grant from the European Research Council to develop catalysts based on nature. These gold(I) and gold(III)-catalytic tools look to promote the synthesis of biologically relevant small molecules with high levels of stereocontrol. She was promoted to Professor in 2013. Nevado develops computational tools to study biological processes in an effort to understand cancer metastasis and progression.
She serves on the editorial board of the ACS Central Science and the advisory board of the Reaxys Doctoral Prize.
Awards and honours
2008 Spanish Royal Society of Chemistry Young Investigator Award
2011 Thieme Chemistry Journals Award
2011 Chemical Society Review Emerging Investigator Award
2013 Swiss Chemical Society Werner Prize
2019 Royal Society of Chemistry Organometallic Chemistry
2021 Margaret Faul Women in Chemistry Award
Selected publications
References
Autonomous University of Madrid alumni
1977 births
Spanish women chemists
Organic chemists
Academic journal editors
Academic staff of the University of Zurich
Living people | Cristina Nevado | [
"Chemistry"
] | 496 | [
"Organic chemists"
] |
66,916,675 | https://en.wikipedia.org/wiki/QTY%20Code | The QTY Code is a design method to transform membrane proteins that are intrinsically insoluble in water into variants with water solubility, while retaining their structure and function.
Similar structures of amino acids
The QTY Code is based on two key molecular structural facts: 1) all 20 natural amino acids are found in alpha-helices regardless of their chemical properties, although some amino acids have a higher propensity to form an alpha-helix; and, 2) several amino acids share striking structural similarities despite their very different chemical properties. These may be paired as: Glutamine (Q) vs Leucine (L); Threonine (T) vs Valine (V) and Isoleucine (I); and Tyrosine (Y) vs Phenylalanine (F). The QTY Code systematically replaces water-insoluble amino acids (L, V, I and F) with water-soluble amino acids (Q, T and Y) in transmembrane alpha-helices. Thus, its application to membrane proteins changes the water-insoluble form of membrane proteins into water-soluble variants. The QTY Code was specifically conceived to render G protein-coupled receptors (GPCRs) into a water-soluble form. Despite substantial transmembrane domain changes, the QTY variants of GPCRs maintain stable structure and ligand binding activities.
Hydrogen bond interactions between water and the amino acids
The side chain of glutamine (Q) can form 4 hydrogen bonds with 4 water molecules. There are 2 hydrogen donors from nitrogen and 2 hydrogen acceptors for oxygen. The –OH group of threonine (T) and tyrosine (Y) can form 3 hydrogen bonds with 3 water molecules (2 H-acceptors and 1 H-donor). Color code: Green = carbon, red = oxygen, blue = nitrogen, gray = hydrogen, yellow disks = hydrogen bonds.
Three types of alpha-helices and with nearly identical molecular structure
There are 3 types of alpha-helices and with nearly identical molecular structure, namely: a) 1.5Å per amino acid rise, b) 100˚ per amino acid turn, c) 3.6 amino acids and 360˚ per helical turn, and d) 5.4Å per helical turn. The 3 types of alpha-helices are: 1) mostly hydrophobic amino acids including Leucine (L), Isoleucine (I), Valine (V), Phenylalanine (F), Methionine (M) and Alanine (A) that are commonly found as the helical transmembrane segments in membrane proteins; 2) mostly hydrophilic amino acids including Aspartic acid (D), Glutamic acid (E), Glutamine (Q), Lysine (K), Arginine (R), Serine (S), Threonine (T), Tyrosine (Y) that are commonly found on the out layer in water-soluble globular proteins; 3) mixed hydrophobic and hydrophilic amino acids that are partitioned in 2 faces: hydrophobic face and hydrophilic face, in an analogy, like our fingers with front and back. These alpha-helices sometimes attach to surface of membrane lipid bilayer, or partially buried to the hydrophobic core and partially close to the surface of water-soluble globular proteins.
The QTY code
The QTY Code is likely universally applicable and also reversible, namely, Q changes to L, T changes to V and I, and Y changes to F. The QTY Code has been successful in designing many water-soluble variants of chemokine receptors and cytokine receptors. The QTY Code may likely be successfully applied to other water-insoluble aggregated proteins. The QTY Code is robust and straightforward: it is the simplest tool to carry out membrane protein design without sophisticated computer algorithms. Thus, it can be used broadly. The QTY Code has implications for designing additional GPCRs and other membrane proteins including cytokine receptors that are directly involved in cytokine storm syndrome.
The QTY Code has also been applied to cytokine receptor water-soluble variants with the aim of combatting the cytokine storm syndrome (also called cytokine release syndrome) suffered by cancer patients receiving CAR-T therapy. This therapeutic application may be equally applicable to severely infected COVID-19 patients, for whom cytokine storms often lead to death.
References
Further reading
Medicinal chemistry
Biochemistry | QTY Code | [
"Chemistry",
"Biology"
] | 956 | [
"Biochemistry",
"Medicinal chemistry",
"nan"
] |
66,917,811 | https://en.wikipedia.org/wiki/1-Hexyne | 1-Hexyne is a hydrocarbon consisting of a straight six-carbon chain having a terminal alkyne. Its molecular formula is . A colorless liquid, it is one of three isomers of hexyne. It is used as a reagent in organic synthesis.
Synthesis and reactions
1-Hexyne can be prepared by the reaction of monosodium acetylide with butyl bromide:
Its reactivity illustrates the behavior of terminal alkylacetylenes. The hexyl derivative is common test substrate because it is conveniently volatile. It undergoes deprotonation at C-3 and C-1 with butyl lithium:
This reaction allows alkylation at the 3-position.
Catechol borane adds to 1-hexyne to give the 1-hexenyl borane.
1-Hexyne reacts with diethyl fumarate to produce .
See also
2-Hexyne
3-Hexyne
References
Alkynes | 1-Hexyne | [
"Chemistry"
] | 203 | [
"Organic compounds",
"Alkynes"
] |
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