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72,238,792 | https://en.wikipedia.org/wiki/Hunt%20effect%20%28color%29 | The Hunt effect or Luminance-on-colorfulness effect comprises an increase in colorfulness of a color with increasing luminance. The effect was first described by RWG Hunt in 1952.
Hunt noted that this effect occurs at low luminance levels. At higher luminance, he noted a hue shift of colors to be more blue with higher luminance, which is now known as the Bezold–Brücke effect. The Hunt effect is related to the Helmholtz–Kohlrausch effect, where a saturated stimulus is seen to be brighter than less saturated or achromatic stimuli.
See also
Opponent process
Purkinje shift
Abney effect
References
Color appearance phenomena | Hunt effect (color) | [
"Physics"
] | 144 | [
"Optical phenomena",
"Physical phenomena",
"Color appearance phenomena"
] |
72,239,371 | https://en.wikipedia.org/wiki/David%20Dye%20%28metallurgist%29 | David Dye is a Professor of Metallurgy at Imperial College London. Dye specialises in fatigue and micromechanics of aerospace and nuclear materials, mainly Ni/Co superalloys, titanium, TWIP steel, and Zirconium alloys.
life and career
Early life and education
Dye completed a Bachelor of Arts degree in Natural Sciences in 1997 at the University of Cambridge, followed by a PhD on the Mechanical effects of welding superalloys in 2000, supervised by Roger Reed.
Research and career
After graduating from the University of Cambridge, Dye worked for a short period as Junior Associate at Mitchell Madison Group from October 2000 until March 2001, before going back to the Department of Materials Science and Metallurgy, the University of Cambridge as a postdoctoral research associate also for a very short stint in 2001. He then joined the National Research Council (NRC) of Canada as Visiting fellow from late 2001 until 2003, working at the neutron spectroscopy facility at the AECL Chalk River Laboratories in Ontario, Canada. He then moved to the Department of Materials, Imperial College London as lecturer, and became a professor in 2015.
David Dye teaches metallurgy, and his research focuses primarily on the micromechanics, design, and fatigue processes of titanium and nickel/cobalt superalloys, with side interests in zirconium, twinning-induced plasticity steels, and superelastic NiTi-based alloys. Most of his work is done in collaboration with Rolls-Royce and other industries, including nuclear and aerospace.
Dye is an experimentalist. His work involves using Electron backscatter diffraction and traditional lab-based characterisation methods, transmission electron microscopy (TEM), neutron and X-rays synchrotron at facilities like ISIS Neutron and Muon Source, Diamond Light Source, European Synchrotron Radiation Facility, and in situ microbeam Laue synchrotron diffraction.
Public engagement
Dye runs a Youtube channel, personal blog, and has courses on Coursera to teach metallurgy, mathematics and data analysis, continuum mechanics, and engineering Alloys. Dye also is a scientific witness to the Science and Technology Committee of the UK parliament.
Awards and honours
2002 and 2005 Grossman Award, ASM International
2005 Grunfeld Medal, Institute of Materials, Minerals and Mining (IOM3)
2010 Harvey Flower Titanium prize, Institute of Materials, Minerals and Mining
2014 Defence Aerospace award, Rolls-Royce
2017 Cook/Ablett Medal, Institute of Materials, Minerals and Mining
2018 EPD Division Science awards, The Minerals, Metals & Materials Society (TMS)
2022 Silver Medal, Acta Materialia
Selected publications
R.J. Talling, R.J. Dashwood, M. Jackson, D. Dye, On the mechanism of superelasticity in Gum metal, Acta Materialia, Volume 57, Issue 4, 2009, Pages 1188-1198, ISSN 1359-6454, doi: 10.1016/j.actamat.2008.11.013.
N.G. Jones, R.J. Dashwood, M. Jackson, D. Dye, β Phase decomposition in Ti–5Al–5Mo–5V–3Cr, Acta Materialia, Volume 57, Issue 13, 2009, Pages 3830-3839, ISSN 1359-6454, doi: 10.1016/j.actamat.2009.04.031.
N.G. Jones, R.J. Dashwood, D. Dye, M. Jackson, Thermomechanical processing of Ti–5Al–5Mo–5V–3Cr, Materials Science and Engineering: A, Volume 490, Issues 1–2, 2008, Pages 369-377, ISSN 0921-5093, doi: 10.1016/j.msea.2008.01.055.
K.M. Rahman, V.A. Vorontsov, D. Dye, The effect of grain size on the twin initiation stress in a TWIP steel, Acta Materialia, Volume 89, 2015, Pages 247-257, ISSN 1359-6454, doi: 10.1016/j.actamat.2015.02.008.
References
External links
David Dye at Imperial College London
David Dye's channel on YouTube.
Living people
British metallurgists
Academics of Imperial College London
Year of birth missing (living people)
Metallurgists | David Dye (metallurgist) | [
"Chemistry",
"Materials_science"
] | 910 | [
"Metallurgists",
"Metallurgy"
] |
72,239,449 | https://en.wikipedia.org/wiki/Toshmuhammad%20Qori-Niyoziy | Toshmuhammad Qori-Niyoziy (Uzbek Cyrillic: Тошмуҳаммад Ниёзович Қори-Ниёзий, , Tashmukhamed Niyazovich Kary-Niyazov; — 17 March 1970) was an Uzbek mathematician and historian who served as the first president of the Academy of Sciences of the Uzbek SSR.
Early life
Born in Khujand on to a shoemaker, he initially received schooling in a maktab, but attended for less than a year due to abuse from the teacher. His family went on to move to Skobelev (now Fergana), where he eventually attended a Russian school and graduated with excellent marks in the mid-1910s. In 1917, he became a teacher at a school he founded in Kokand, which quickly became a regional school. Initially having volunteered to serve as head of schools for the Skobelev district, he went on to serve as director of the Uzbek Pedagogical College in Kokand from 1920 to 1925. Several years later he graduated from the Faculty of Physics and Mathematics at Central Asian State University in Tashkent; he defended his thesis in Uzbek.
His wife Oishakhon, who he married in 1920 in a Muslim ceremony, was one of the first women teachers in the Uzbek SSR. She frequently advised him on his philology work, including the first Uzbek dictionaries that they worked on together.
Career
Whilst a university student, he was tasked with teaching advanced math classes such as analytic geometry in the Uzbek language. After graduating he continued to teach university-level mathematics in the Uzbek language, becoming the first Uzbek to receive the title of professor in 1931. That year, he became a member of the Communist Party. From then to 1933 he served as a rector at the university, although he did not receive his doctorate of physics and mathematics until 1939. He then became the Deputy Chairman of the Committee of the Uzbek SSR for Science, Culture and Art, and worked on the transition of the Uzbek alphabet to a Cyrillic script. He also devoted a considerable amount of time to researching the history of Uzbekistan and historic academic works, with a special focus on astronomy and archaeology. As part of his research about early astronomy in what is present-day Uzbekistan, he had to read through numerous Arabic manuscripts. In addition to his academic work, he held various political offices, serving as a deputy in the Supreme Soviet of the USSR for the 1st and 2nd convocations. He also authored numerous textbooks and academic papers, including the first Uzbek-language math textbooks and papers about Uzbek culture and society.
World War II
In June 1941, he led alongside Mikhail Gerasimov a scientific expedition to examine the tomb of Timur in Samarkand. According to local legend, an inscription on the tomb threatened to bring about a catastrophe to whoever opened it, and shortly after it was opened, Nazi Germany began invading the Soviet Union. After the remains were reburied with Muslim rites in 1942, some in Uzbekistan credited the Soviet victory in the Battle of Stalingrad to the reburial.
After the German invasion of the Soviet Union, his only son Shavkat applied to go to the frontlines with the Red Army. Being skilled in mathematics like his father, he was chosen for artillery school. After surviving the war, Shavkat went on to graduate from the F.E. Dzerzhinky Military Academy and follow in his father's footsteps with a career in mathematics, but specialized in ballistics and rocket technology.
When the Academy of Sciences of the Uzbek SSR was established in 1943, Qori-Niyazov was made its first president and held the post until 1947.
Postwar
In 1946 Qori-Niyoziy became a professor at the Tashkent Institute of Engineers and Agricultural Mechanization. For his paper "Ulugbek's Astronomical School" he was awarded the Stalin Prize. In 1954 he became a member of the International Astronomical Union, in 1967 he became a corresponding member of the International Academy of the History of Science, and that same year on 1 September he was awarded the title Hero of Socialist Labour for his work promoting academics in the Uzbek SSR. His work included serving as editor-in-chief of the Uzbek science magazine Fan va turmush and deputy chairman of the board for preserving historic and cultural monuments of Uzbekistan. During the course of his work, he travelled to various foreign countries including Afghanistan, Bulgaria, India, Italy, and Japan. He died on 17 March 1970 and was buried in the Chigatoy Cemetery.
Awards and honors
Honoured Scientist of the Uzbek SSR (1939)
Three Orders of Lenin (4 November 1944, 1 March 1965, 1 September 1967)
Three Orders of the Red Banner of Labour (23 January 1946, 16 January 1950, 27 October 1953)
Stalin Prize 3rd class (1952)
Hero of Socialist Labour (1 September 1967)
Beruniy State Prize (1970)
Order of Outstanding Merit (23 August 2002)
Notes
References
1897 births
1970 deaths
20th-century mathematicians
People from Khujand
Communist Party of the Soviet Union members
National University of Uzbekistan alumni
First convocation members of the Supreme Soviet of the Soviet Union
Second convocation members of the Supreme Soviet of the Soviet Union
Heroes of Socialist Labour
Recipients of the Stalin Prize
Recipients of the Order of Lenin
Recipients of the Order of the Red Banner of Labour
Historians of astronomy
Soviet mathematicians
Soviet memoirists
Uzbekistani mathematicians
Recipients of the Order of Outstanding Merit | Toshmuhammad Qori-Niyoziy | [
"Astronomy"
] | 1,124 | [
"People associated with astronomy",
"Historians of astronomy",
"History of astronomy"
] |
72,241,256 | https://en.wikipedia.org/wiki/Hymenogaster%20subalpinus | Hymenogaster subalpinus is a species of mushroom-forming fungus in the family Hymenogastraceae.
Refererence
Hymenogastraceae
Fungi described in 1966
Taxa named by Alexander H. Smith
Fungus species | Hymenogaster subalpinus | [
"Biology"
] | 50 | [
"Fungi",
"Fungus species"
] |
72,242,506 | https://en.wikipedia.org/wiki/Data%20divide | The data divide is the unequal relationship between those capable of collecting, storing, mining, and general management of immense volumes of data, and those whose data is collected. Using the framework of the digital divide, the data divide posits that the evolving nature of data and big data has created divisions and inequalities in data ownership, access, analysis, collection, and the manipulation of personal data generated by information and communications technologies (ICTs).
Theoretical framework
Early research in the digital divide concentrated on the divisions of access to information and digital technologies, demonstrating a split between the "haves" and the "have-nots": those able to access and use digital technologies versus those who do not. Divisions were found to occur along multiple lines of inequality, including education, economic income, race, and gender. The digital divide has several dimensions of access, including access to equipment or hardware, ownership, support networks, digital literacy, skill to use/navigate user interfaces, and so on. The Ada Lovelace Institute notes that the digital divide has exacerbated a data divide. As a result, the dimensions of access present within the digital divide are still present. The data divide additionally puts in contrast the "haves" who have access to large-scale datasets and the "have-nots" who do not have access to large-scale datasets nor the capability to navigate them. For example, private companies, often social media companies, are the only ones who have access to extensive social data. Boyd and Crawford suggest divisions are also emphasized through research and universities: well-funded universities can buy access to datasets and the students who attend would be more likely to be bridged into work within the same social media companies, while less prestigious institutions would be less likely to afford their students the same opportunities.
COVID-19 pandemic
The COVID-19 pandemic resulted in governments worldwide issuing stay-at-home orders, lockdowns, quarantines, restrictions, and closures. Interruptions to schooling, work, business, and other public service operations caused a massive shift to moving otherwise in-person activities online. Operations like doctor's visits, online schooling, shipping, and remote working require access to high-speed or broadband internet access and digital technologies. This mass adoption of data-driven digital technologies is what the Ada Lovelace Institute describes as a digital surge. In a report with the Health Foundation, the Ada Lovelace Institute found the four key elements that emerged through a public attitudes survey: a data divide based on access to data-driven technologies, a data divide based on awareness and skill, a data divide based on comfort with using health-related tracking apps, and a data divide based on choosing not to use health-tracking apps. In this, the Ada Lovelace Institute stressed the data divide in users not being able to access data that may benefit them and the dangers of not being represented to address health inequalities.
Aspects
Infrastructure
General advances in technology, computing power, storage, and information management practices have enabled huge quantities of data to be both produced and analyzed.
Tim Berners-Lee notes an increasing detachment between people and their own personal data, that regular users of digital devices or other services do not have the same capabilities to utilize data to the extent that ICTs or data brokerage firms do. Berners-Lee argues that if personal data has the potential to benefit users, then users should be able to access and utilize them. However, Mark Andrejevic notes that even if users were given access to their own data, they would not be able to put it to use as effectively as data collectors because user data is not collected in isolation. Instead, data collectors accumulate data within a broader environment. By connecting and individual's interests to the profiles of other users, collectors can filter through content and interest patterns to recommend the content they may deem relevant to an individual. The capacities for storing, collecting, and analyzing data requires the necessary technological infrastructures, datasets, software, and processing power. Being able to extract information out of large datasets necessitates access to machines, databases, and advanced algorithms.
Smart city infrastructures are emblematic of the ways that sensors facilitated by big data technologies capture information to manage issues in urban city centers. Processing technologies may relate to issues around finance, trade, social welfare, etc. For example, municipal governments may identify and monitor citizens, companies, organizations, update their records, map profiles, perform data analyses to spot trends or issues, track services, and so on. Many smart city systems track data on a granular level, and while some governments have opted for open data approaches with dashboards and KPIs on display, some governments are not fully transparent and do not share their processes with the public. In this sense, the data divide is represented by governments capturing real-time data on citizens, whose data is used to further manage and govern city centers.
Digital literacy
Being able to work with large-scale datasets and having the skills to navigate them requires types of knowledge that tend to only be available to those who have access to advanced machines, databases, and algorithms. Large databases enabled by big data are too large for any person or any group of people to understand on their own, which is why companies use tools and technologies assisted by artificial intelligence, algorithms, and so on. This divide is not only in the sense of those who have and those who do not. This divide also exists in categorical processes, ontological ways of thinking of data, and application of data. Companies with access to data are able to engage with robust and complex means of sorting. Individual use of collected data simply cannot measure up, especially if enabled within new work environments or communities without proper knowledge sharing or training. For example, failures to adopt new technologies into key industries such as agriculture represents aspects in both the digital and data divide. Lack of data literacy can lead to data deluges – the burden of having and overwhelming amount of data without the capability to extract any meaningful information from datasets.
Implications
A lack of collected information can create disparities which can eventually lead to information poverty. Information poverty stems from a lack of data about a given concept, where the data poverty can have a cumulative effect. This can snowball from individuals to governments on a national scale. This may become especially problematic when considering that those with access to information can act on data and thereby influence the lives of others in ways that people may not be able to concretely see. For example, a 2007 report from the World Health Organization shows that health information is one of the six fundamental building blocks of a well-functioning health system. Access to quality health data is essential to resolving outbreaks, sicknesses, or other disparities in health; however, many countries, particularly in the Global South, do not have access to the relevant data sources that would allow them to otherwise address health inequities.
Solutions
Overcoming the digital divide itself may provide populations with the means to access information and solve digital inequities, however this would also mean further exacerbating the data divide.
Data activists and information professionals do have the ability to help bridge the data divide through social action including crowdsourcing, citizen science, data cooperatives, hackathons, and civic hacking. These events seek to disrupt and challenge the status quo by cooperating with citizens to better understand quality of access, raise awareness, and allow citizens to generate data for their own uses.
References
Information society | Data divide | [
"Technology"
] | 1,532 | [
"Computing and society",
"Information society"
] |
72,242,728 | https://en.wikipedia.org/wiki/DREAM%20Challenges | DREAM Challenges (Dialogue for Reverse Engineering Assessment and Methods) is a non-profit initiative for advancing biomedical and systems biology research via crowd-sourced competitions. Started in 2006, DREAM challenges collaborate with Sage Bionetworks to provide a platform for competitions run on the Synapse platform. Over 60 DREAM challenges have been conducted over the span of over 15 years.
Overview
DREAM Challenges were founded in 2006 by Gustavo Stolovizky from IBM Research and Andrea Califano from Columbia University. Current chair of the DREAM organization is Paul Boutros from University of California. Further organization spans emeritus chairs Justin Guinney and Gustavo Stolovizky, and multiple DREAM directors.
Individual challenges focus on tackling a specific biomedical research question, typically narrowed down to a specific disease. A prominent disease focus has been on oncology, with multiple past challenges focused on breast cancer, acute myeloid leukemia, and prostate cancer or similar diseases. The data involved in an individual challenge reflects the disease context; while cancers typically involve data such as mutations in the human genome, gene expression and gene networks in transcriptomics, and large scale proteomics, newer challenges have shifted towards single cell sequencing technologies as well as emerging gut microbiome related research questions, thus reflecting trends in the wider research community.
Motivation for DREAM Challenges is that via crowd-sourcing data to a larger audience via competitions, better models and insight is gained than if the analysis was conducted by a single entity. Past competitions have been published in such scientific venues as the flagship journals of the Nature Portfolio and PLOS publishing groups. Results of DREAM challenges are announced via web platforms, and the top performing participants are invited to present their results in the annual RECOMB/ISCB Conferences with RSG/DREAM organized by the ISCB.
While DREAM Challenges have emphasized open science and data, in order to mitigate issues rising from highly sensitive data such as genomics in patient cohorts, "model to data" approaches have been adopted. In such challenges participants submit their models via containers such as Docker or Singularity. This allows retaining confidentiality of the original data as these containers are then run by the organizers on the confidential data. This differs from the more traditional open data model, where participants submit predictions directly based on the provided open data.
Challenge organization
DREAM challenge comprises a core DREAM/Sage Bionetworks organization group as well as an extended scientific expert group, who may have contributed to creation and conception of the challenge or by providing key data. Additionally, new DREAM challenges may be proposed by the wider research community. Pharmaceutical companies or other private entities may also be involved in DREAM challenges, for example in providing data.
Challenge structure
Timelines for key stages (such as introduction webinars, model submission deadlines, and final deadline for participation) are provided in advance. After the winners are announced, organizers start collaborating with the top performing participants to conduct post hoc analyses for a publication describing key findings from the competition.
Challenges may be split into sub-challenges, each addressing a different subtopic within the research question. For example, regarding cancer treatment efficacy predictions, these may be separate predictions for progression-free survival, overall survival, best overall response according to RECIST, or exact time until event (progression or death).
Participation
During DREAM challenges, participants typically build models on provided data, and submit predictions or models that are then validated on held-out data by the organizers. While DREAM challenges avoid leaking validation data to participants, there are typically mid-challenge submission leaderboards available to assist participants in evaluating their performance on a sub-sampled or scrambled dataset.
DREAM challenges are free for participants. During the open phase anybody can register via Synapse to participate either individually or as a team. A person may only register once and may not use any aliases.
There are some exceptions, which disqualify an individual from participating, for example:
Person has privileged access to the data for the particular challenge, thus providing them with an unfair advantage.
Person has been caught or is under suspicion of cheating or abusing previous DREAM Challenges.
Person is a minor (under age 18 or the age of majority in jurisdiction of residence). This may be alleviated via parental consent.
See also
List of crowdsourcing projects
Critical Assessment of Function Annotation (CAFA)
Critical Assessment of Genome Interpretation (CAGI)
Critical Assessment of Prediction of Interactions (CAPRI)
Critical Assessment of protein Structure Prediction (CASP)
Kaggle
References
Applied machine learning
Bioinformatics
Computer science competitions
Crowdsourcing
Forecasting competitions
Molecular modelling
Programming contests | DREAM Challenges | [
"Chemistry",
"Engineering",
"Biology"
] | 925 | [
"Biological engineering",
"Molecular physics",
"Bioinformatics",
"Molecular modelling",
"Theoretical chemistry"
] |
72,243,076 | https://en.wikipedia.org/wiki/Glossary%20of%20cellular%20and%20molecular%20biology%20%28M%E2%80%93Z%29 | This glossary of cellular and molecular biology is a list of definitions of terms and concepts commonly used in the study of cell biology, molecular biology, and related disciplines, including molecular genetics, biochemistry, and microbiology. It is split across two articles:
Glossary of cellular and molecular biology (0–L) lists terms beginning with numbers and those beginning with the letters A through L.
Glossary of cellular and molecular biology (M–Z) (this page) lists terms beginning with the letters M through Z.
This glossary is intended as introductory material for novices (for more specific and technical detail, see the article corresponding to each term). It has been designed as a companion to Glossary of genetics and evolutionary biology, which contains many overlapping and related terms; other related glossaries include Glossary of virology and Glossary of chemistry.
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
See also
Introduction to genetics
Outline of genetics
Outline of cell biology
Glossary of biology
Glossary of chemistry
Glossary of genetics and evolutionary biology
References
Further reading
External links
National Human Genome Research Institute (NHGRI) Talking Glossary of Genomic and Genetic Terms
Interactive, labeled animal cell from SwissBioPics
Glossary
Genetics
Molecular-biology-related lists
Wikipedia glossaries using description lists | Glossary of cellular and molecular biology (M–Z) | [
"Chemistry",
"Biology"
] | 264 | [
"Glossaries of biology",
"Molecular-biology-related lists",
"Genetics",
"Molecular biology"
] |
72,243,857 | https://en.wikipedia.org/wiki/FinVect | In the mathematical field of category theory, FinVect (or FdVect) is the category whose objects are all finite-dimensional vector spaces and whose morphisms are all linear maps between them.
Properties
FinVect has two monoidal products:
the direct sum of vector spaces, which is both a categorical product and a coproduct,
the tensor product, which makes FinVect a compact closed category.
Examples
Tensor networks are string diagrams interpreted in FinVect.
Group representations are functors from groups, seen as one-object categories, into FinVect.
DisCoCat models are monoidal functors from a pregroup grammar to FinVect.
See also
FinSet
ZX-calculus
category of modules
References
Categories in category theory
Dimension | FinVect | [
"Physics",
"Mathematics"
] | 156 | [
"Geometric measurement",
"Mathematical structures",
"Physical quantities",
"Vector spaces",
"Space (mathematics)",
"Categories in category theory",
"Category theory",
"Theory of relativity",
"Dimension"
] |
72,244,439 | https://en.wikipedia.org/wiki/Deutschlandticket | The () often shorted to the D-Ticket, also known as the 49-Euro-Ticket, is a subscription public transport ticket for all local public transport, valid in the whole of Germany, that costs 49 euros per month. The Scholz cabinet introduced it in May 2023 as a permanent successor to the 9-Euro-Ticket which had been offered in Summer 2022. The German federation () and the federal states () initially participate in the financing with 1.5 billion euros per year until 2025.
At the beginning of January 2025, the price of the ticket was raised to 58 per month.
Ticket conditions
Validity
The ticket is valid on all local and regional buses, trams, metros, S-Bahn trains, and local and regional trains (RB/RE) across the whole of Germany, except on few RE trains operated by DB Fernverkehr.
It is usually valid on international eligible trains from/to end stations in a neighbour country, if operated by a German operator. Deutschlandticket holders can also go to a number of border tariff stations outside Germany using their passes including; Tønder () in Denmark, Wissembourg (Gare de Wissembourg) in France, Hengelo (over Oldenzaal), and Venlo in the Netherlands, Basel in Switzerland and Świnoujście () in Poland.
It is not valid on most of the long-distance trains (such as Intercity Express (ICE), Intercity (IC) and Eurocity (EC) trains operated by Deutsche Bahn) and on long-distance bus coaches (such as those operated by Flixbus). There are exceptions for long-distance trains, which are co-financed by cities and states.
The ticket is only valid for transportation in second class. Often it is possible to buy upgrades to first class (if available) from the concerned operator. Children under 6 years old travel for free, while older children need their own ticket. The Deutschlandticket does not include transportation for pets or for bicycles in cases where they require a separate ticket.
Sales
The Deutschlandticket was originally sold as a monthly subscription at a cost of 49 Euros per month which increased to 58 Euros in January 2025. The ticket is valid for a calendar month, and is automatically renewed, with payment taken by SEPA direct debit from the user's bank account or by credit card. The subscription can be cancelled by the 10th day of each month. Users wishing to purchase a new subscription for the current month on the 11th day of the month or later must pay for at least the current and the following calendar month. The mo.pla app allows users to cancel their Deutschlandticket subscription up to the second-last day of the month.
The Deutschlandticket is sold by participating local transit authorities. It is issued as a digital ticket via mobile apps offered by local transit authorities. It can also be issued on a chip smartcard using the "eTicket Deutschland" standard. Employers can subsidise the ticket for their employees, and university students can upgrade their "Semesterticket" to a Deutschlandticket. Some communities have additionally subsidised the ticket for those on low income, senior citizens and apprentices. The city of Tübingen has gone as far as subsidising the ticket for every resident, so they can get it for 34 euros per month. The local council in the city of Stuttgart has offered the Deutschlandticket to its employees as an employee benefit.
The BahnCard 100, a rail card offered by Deutsche Bahn allowing unlimited travel on its trains, includes a Deutschlandticket at no additional charge.
History
After the start of the Russian invasion of Ukraine, energy prices in Germany rose significantly. In response, the government introduced the heavily subsidized 9-Euro-Ticket, which allowed unlimited use of public local transportation across Germany at a cost of 9 euros per calendar month. It was available for June, July, and August 2022. After the end of this 3-month period, politicians called for a permanent successor ticket that would offer similar simplicity, though there was debate about the price.
At the end of November 2022, transport ministers reaffirmed their commitment to the monthly ticket for 49 euros, and it was planned to start in April 2023, as a start in January was considered too early for implementation. The start was delayed further by one month as there was opposition from the local and regional transportation services like the Munich MVV that wanted more funding from the federal and the state governments.
On 31 March 2023, the Bundesrat approved the bill passed by the Bundestag for a nationwide ticket for local and regional public transportation at a monthly price of 49 euros. The monthly tickets started in May 2023, but could only be purchased by subscription. There are no paper tickets for the subscription – with the possible exception at the start-up phase; the users have to authenticate digitally (either via smartphone app or chip card).
The ticket price is to be adjusted to inflation each year, although the 49 euro price is intended to be fixed for at least the first two years of operation of the ticket.
On 31 July, three months after the introduction of the Deutschlandticket, the transport ministry reported that 11 million people subscribed to the ticket, with 5 million being existing subscribers to monthly transport passes, 5 million new subscribers from existing public transport ticket holders and one million new users of public transport. On 13 September, the Hamburg transport agency reported that it had sold over a million subscriptions.
Since the summer of 2023, Federal Transport Minister Volker Wissing (FDP) had argued with the federal states about the financing of the ticket. The financing of the ticket is unclear. Both sides have so far contributed 1.5 billion euros annually. If there is not enough money, the federal and state governments currently share the additional costs. The federal government rejects further financial commitments from 2024.
At the beginning of December 2023, the Stendal district decided that the ticket will no longer be valid on its buses from January 1, 2024. This would have meant that the Deutschlandticket would no longer be valid across the board. However, the district council reverted its decision two weeks later and the Deutschlandticket remains a valid ticket in the Stendal district.
Interest outside Germany
Due to the popularity and interest in the Deutschlandticket in Germany, other countries expressed interest in introducing a similar scheme in their country.
Portugal
On 30 June 2023, influenced by Deutschlandticket, the eco-socialist LIVRE party proposed a monthly rail pass for the regional trains by the state-owned rail operator Comboios de Portugal in the country's annual budget. The proposal passed in parliament, and the Portuguese government said it was introducing a 49 euros per month regional rail pass called the Passe Ferroviário Nacional (National Train Pass) from 1 August 2023. It would allow unlimited travel on all regional trains, known as comboios regionais apart from the tourist trains like the , and suburban rail services in Lisbon, Porto and Coimbra.
Critics have said that due to the rules and exclusions of the pass, there are virtually no regional rail services in the middle of the country and frequent strikes by rail workers make the pass worthless.
France
On 9 June 2023, German federal transport minister Volker Wissing said in an interview with Berliner Morgenpost, that he was talking to his French counterpart Clément Beaune about the scheme in a meeting between the two ministers during a discussion about a Franco-German student travel scheme.
In an interview with French YouTuber Hugo Travers on 4 September 2023, French president Emmanuel Macron said his government is looking at a French equivalent of the Deutschlandticket. Later that week on 7 September, on France 2's breakfast programme Télématin, Beaune said the transport ministry was provisionally working on a similar scheme called "Pass Rail" which would come in the summer of 2024. The ticket would allow unlimited travel throughout France on the country's regional trains, the TERs and the regular Intercités for 49 euros per month. Beaune said the government was talking to local authorities about including local bus and trams as well.
Reactions to the proposal were mixed, with the region of Grand Est being supportive of the idea, while the region of Hauts-de-France was critical particularly over costs, pointing out that the region already subsidises its TER to the tune of 530 million euros. The president of the Île-de-France region Valérie Pécresse said in an interview on France 3 Paris Île-de-France, that the costs for such a scheme would be around 1.8 billion euros for the region, making it unaffordable. Wissing has said he would like to interlink the two schemes, so that persons could use either pass in each other's countries.
On 27 September, Beaune and the presidents of all regions came together in Saint-Malo to begin discussions on financing such a scheme, together with general rail finance such as track fees and rolling stock. It is hoped that such a subscription would be available by the summer of 2024.
United Kingdom
A report produced for Greenpeace by the Greengauge 21 think tank suggested that a similar scheme might increase usage of UK train routes and reduce the climate impact of fossil fuel powered vehicles. The Department for Transport responded to the report by stating that the UK Government has no plans to implement a similar scheme at the present time.
See also
Klimaticket in Austria
365-Euro-Ticket in Vienna
External links
Federal government's information on the Deutschlandticket
Deutsche Bahn's page on the Deutschlandticket
Rhein-Main-Verkehrsverbund's page on the Deutschlandticket
References
2022 in politics
Emissions reduction
Euro
Fare collection systems in Germany
Public transport in Germany
Scholz cabinet
Public transport tickets
Environmental policies approved in 2023 | Deutschlandticket | [
"Chemistry"
] | 2,025 | [
"Greenhouse gases",
"Emissions reduction"
] |
72,244,570 | https://en.wikipedia.org/wiki/Valentin%20Kargin | Valentin Alekseyevich Kargin (; 23 January 1907 – 21 October 1969) was a Soviet and Russian chemist who specialized in physical chemistry and established research in polymer chemistry in the Soviet Union. He considered polymerization as a phase transition.
Kargin was born Yekaterinoslav where his father Aleksei was a mining engineer. He went to school at Klin where the family moved. After graduation in 1922 he worked as a laboratory assistant and in 1924 he became an assistant at the Karpov Institute of Physical Chemistry. In 1925 he joined the Moscow State University and received a degree in 1930 and a doctorate in 1936. Kargin began to work on colloid chemistry, metal organosols and then began to work with macromolecules of cellulose with applications for the production of fibre. In 1940 he was involved in the production of photographic films. In 1943 he was awarded a Stalin Prize for his work in developing protective agents against chemical warfare for the army. He was also involved in the production of transparent organochemical polymers particularly for use in aircraft. After World War II he worked on polymerization reactions and the use of catalysts to produce polymers of various properties. These included polymers with fluorine that could withstand heat and other physical stresses. He also found polymers with semiconductor properties which were used for radar technology. He trained a number of chemists including V. A. Kabanov, N. A. Plate, V. P. Shibaev, N. F. Bakeev, A. B. Zezin, and A. L. Volynsky. He also began an encyclopedia of polymers. The Kargin Research Institute of Polymers was named in his honour in 1969.
Kargin died from a ruptured aorta and he was buried at the Novodevichy Cemetery in Moscow.
References
External links
Biography in Russian
1907 births
1969 deaths
20th-century Russian chemists
Scientists from Dnipro
Full Members of the USSR Academy of Sciences
Members of the German Academy of Sciences at Berlin
Heroes of Socialist Labour
Recipients of the Stalin Prize
Recipients of the Lenin Prize
Recipients of the Order of Lenin
Recipients of the Order of the Red Banner of Labour
Recipients of the USSR State Prize
Polymer scientists and engineers
Russian physical chemists
Soviet physical chemists
Burials at Novodevichy Cemetery | Valentin Kargin | [
"Chemistry",
"Materials_science"
] | 471 | [
"Polymer scientists and engineers",
"Physical chemists",
"Polymer chemistry"
] |
72,244,689 | https://en.wikipedia.org/wiki/Angus%20Kirkland | Angus Ian Kirkland FInstP FRSC FRMS (born August 1965) is the JEOL Professor of Electron Microscopy at the Department of Materials, University of Oxford. Professor Kirkland specialises in High-resolution transmission electron microscopy and Scanning transmission electron microscopy.
Early life and education
Kirkland completed a Master of Arts in Natural Sciences, and a Doctor of Philosophy at the University of Cambridge in 1989.
Research and career
Kirkland continued at Cavendish Laboratory as post-doctoral fellow until he became Senior Research Associate. He was later elected the Ramsay Memorial Trust Research Fellow.
He then moved to the Department of Materials, University of Oxford where he has led Oxford Electron Image Analysis Group since 2003. He was appointed as professor in 2005, and became the JEOL Professor of Electron Microscopy in 2011. He was the co-director of the University of Oxford’s David Cockayne Centre.
Kirkland research focuses on developing new quantitative techniques for ultra high-resolution electron microscopy, and new imaging detectors. His research also include developing analysis and simulation. He researches nanomaterials inorganic oxides structure and surfaces. The development of new detectors, e.g., Transmission Electron Aberration-Corrected Microscope. Angus Kirkland has an illustrious career with publications in Nature and Science. He led collaborations and grants valued in £million.
As of November 2022, he is the Science Director at the Rosalind Franklin Institute and the electron Physical Science Imaging Centre (ePSIC) at Diamond Light Source. He is also the Editor-in-Chief of Ultramicroscopy.
Awards and honours
Kirkland is a Fellow of the Institute of Physics (FInstP), the Royal Society of Chemistry (FRSC), and the Royal Microscopical Society (FRMS).
Kirkland was awarded the Microscopy Society of America Award for the best paper published (2005). In 2015, he was awarded the Harald Rose Distinguished Lecture Prize. He also received the RMS Alan Agar Medal in 2017.
In 2012, Kirkland was appointed as an Honorary Professor at the centre of HRTEM, Nelson Mandela University, South Africa.
Selected publications
Huilong Fei, Juncai Dong, Yexin Feng, Christopher S. Allen, Chengzhang Wan, Boris Volosskiy, Mufan Li, Zipeng Zhao, Yiliu Wang, Hongtao Sun, Pengfei An, Wenxing Chen, Zhiying Guo, Chain Lee, Dongliang Chen, Imran Shakir, Mingjie Liu, Tiandou Hu, Yadong Li, Angus I. Kirkland, Xiangfeng Duan, Yu Huang (2018-01). General synthesis and definitive structural identification of MN4C4 single-atom catalysts with tunable electrocatalytic activities. Nature Catalysis. 1 (1): 63–72. doi:10.1038/s41929-017-0008-y. ISSN 2520-1158.
Alex W. Robertson, Christopher S. Allen, Yimin A. Wu, Kuang He, Jaco Olivier, Jan Neethling, Angus I. Kirkland, Jamie H. Warner (2012-10-23). Spatial control of defect creation in graphene at the nanoscale. Nature Communications. 3 (1): 1144. doi:10.1038/ncomms2141. ISSN 2041-1723.
Lele Peng, Ziyang Wei, Chengzhang Wan, Jing Li, Zhuo Chen, Dan Zhu, Daniel Baumann, Haotian Liu, Christopher S. Allen, Xiang Xu, Angus I. Kirkland, Imran Shakir, Zeyad Almutairi, Sarah Tolbert, Bruce Dunn, Yu Huang, Philippe Sautet, Xiangfeng Duan (2020-09). A fundamental look at electrocatalytic sulfur reduction reaction. Nature Catalysis. 3 (9): 762–770. doi:10.1038/s41929-020-0498-x. ISSN 2520-1158.
Meyer, Rüdiger R.; Sloan, Jeremy; Dunin-Borkowski, Rafal E.; Kirkland, Angus I.; Novotny, Miles C.; Bailey, Sam R.; Hutchison, John L.; Green, Malcolm L. H. (2000-08-25). Discrete Atom Imaging of One-Dimensional Crystals Formed Within Single-Walled Carbon Nanotubes. Science. 289 (5483): 1324–1326. doi:10.1126/science.289.5483.1324. ISSN 0036-8075.
Warner, Jamie H.; Margine, Elena Roxana; Mukai, Masaki; Robertson, Alexander W.; Giustino, Feliciano; Kirkland, Angus I. (2012-07-13). Dislocation-Driven Deformations in Graphene. Science. 337 (6091): 209–212. doi:10.1126/science.1217529. ISSN 0036-8075.
References
Microscopists
Living people
British materials scientists
Academics of the University of Oxford
Fellows of the Institute of Physics
Fellows of the Royal Microscopical Society
Fellows of the Royal Society of Chemistry
Year of birth missing (living people) | Angus Kirkland | [
"Chemistry"
] | 1,086 | [
"Microscopists",
"Microscopy"
] |
63,520,272 | https://en.wikipedia.org/wiki/David%20Hodgkiss | David Michael William Hodgkiss (June 1948 – 29 March 2020) was a British businessman, and Chairman of Lancashire County Cricket Club between April 2017 and March 2020.
He was Chief Executive of structural steel contractor William Hare Group, a business founded by his grandfather. Hodgkiss's 2014 OBE was awarded for services to manufacturing and export at William Hare.
Hodgkiss served over twenty years at Lancashire County Cricket Club as Committee Member , Treasurer , Vice-Chairman and Chairman , being instrumental in completing a £60 million redevelopment of the Club's Old Trafford Cricket Ground.
He died age 71 in March 2020 after catching COVID-19. The England Cricket Team took to the field against the West Indies at Emirates Old Trafford wearing black armbands in his honour. Farokh Engineer lauded Hodgkiss as the best and the most popular Chairman Lancashire County Cricket Club ever had.
References
1948 births
2020 deaths
Deaths from the COVID-19 pandemic in England
British chief executives
Lancashire County Cricket Club
Officers of the Order of the British Empire
20th-century British businesspeople
21st-century British businesspeople
Alumni of the University of Liverpool
Structural steel | David Hodgkiss | [
"Engineering"
] | 240 | [
"Structural engineering",
"Structural steel"
] |
63,520,779 | https://en.wikipedia.org/wiki/Silurian-Devonian%20Terrestrial%20Revolution | The Silurian-Devonian Terrestrial Revolution, also known as the Devonian Plant Explosion (DePE) and the Devonian explosion, was a period of rapid colonization, diversification and radiation of land plants and fungi on dry lands that occurred 428 to 359 million years ago (Mya) during the Silurian and Devonian periods, with the most critical phase occurring during the Late Silurian and Early Devonian.
This diversification of terrestrial photosynthetic florae had vast impacts on the biotic composition of the Earth's surface, especially upon the Earth's atmosphere by oxygenation and carbon fixation. Their roots also eroded into the rocks, creating a layer of water-holding and mineral/organic matter-rich soil on top of Earth's crust known as the pedosphere, and significantly altering the chemistry of Earth's lithosphere and hydrosphere. The floral activities following the Silurian-Devonian plant revolution also exerted significant influences on changes in the water cycle and global climate, as well as driving the biosphere by creating diverse layers of vegetations that provide both sustenance and refuge for both upland and wetland habitats, paving the way for all terrestrial and aquatic biomes that would follow.
Through fierce competition for sunlight, soil nutrients and available land space, phenotypic diversity of plants increased greatly during the Silurian and Devonian periods, comparable in scale and effect to the explosion in diversity of animal life during the Cambrian explosion, especially in vertical growth of vascular plants, which allowed for expansive canopies to develop, and forever altering the plant evolutions that followed. As plants evolved and radiated, so did arthropods, who became the first established terrestrial animals and some formed symbiotic coevolution with plants. Herbivory, granivory and detritivory subsequently evolved independently among terrestrial arthropods (especially hexapods such as insects, as well as myriapods), molluscs (land snails and slugs) and tetrapod vertebrates, causing plants to in turn develop defenses against foraging by animals.
The Silurian and Devonian terrestrial florae were largely spore-bearing plants (ferns) and significantly different in appearance, anatomy and reproductive strategies to most modern florae, which are dominated by fleshy seed-bearing angiosperms that evolved much later during the Early Cretaceous. Much of these Silurian-Devonian florae had died out in extinction events including the Kellwasser event, the Hangenberg event, the Carboniferous rainforest collapse, and the End-Permian extinction.
Silurian and Devonian life
Rather than plants, it was fungi, in particular nematophytes such as Prototaxites, that dominated the early stages of this terrestrial biodiversification event. Nematophytes towered over even the largest land plants during the Silurian and Early Devonian, only being truly surpassed in size in the Early Carboniferous. The nutrient-distributing glomeromycotan mycorrhizal networks of nematophytes were very likely to have acted as facilitators for the expansion of plants into terrestrial environments, which followed the colonising fungi. The first fossils of arbuscular mycorrhizae, a type of symbiosis between fungi and vascular plants, are known from the Early Devonian.
Land plants probably evolved in the Ordovician. The earliest radiations of the first land plants, also known as embryophytes, were bryophytes, which began to transform terrestrial environments and the global climate in the Ordovician. Baltica was a particularly important cradle for early land plant evolution, with it having a diverse flora by the Darriwilian. ∆199Hg and ∆200Hg excursions reveal that land plants had already spread across much of the Earth's land surface by the Early Silurian. The end of the Homerian glaciation, a glacial phase of the Early Palaeozoic Ice Age, and the corresponding period of global warming marked the first major diversification of plants that produced trilete spores. The later glaciation during the middle Ludfordian, corresponding to the Lau event, led to a major marine regression, creating significant areas of new dry land habitat that were colonised by plants, along with cyanobacterial mats. These newly created terrestrial habitats helped facilitate the global expansion and evolutionary radiation of polysporangiophytes. A warming climate during the subsequent Pridoli epoch lent itself to further floral diversification. During the Wenlock epoch of the Silurian, the first fossils of vascular plants appear in the fossil record in the form of sporophytes of polysporangiophytes. Lycophytes first appeared during the later Ludlow epoch in the form of Baragwanathia, which was an aquatic predecessor of fully terrestrialised lycophytes. Palynological evidence points to Silurian terrestrial floras exhibiting little provincialism relative to present day floras that vary significantly by region, instead being broadly similar across the globe. Plant diversification in the Silurian was aided by the presence of numerous small, rapidly changing volcanic islands in the Rheic Ocean that acted as natural laboratories accelerating evolutionary changes and enabling distinct, endemic floral lineages to arise. Silurian plants rarely reached large sizes, with heights of 13 cm, achieved by Tichavekia grandis, being exceptionally large for the time.
The Devonian witnessed the widespread greening of the Earth's surface, with many modern vascular plant clades originating during this period. Basal members of Euphyllophytina, the clade that includes trimerophytes, ferns, progymnosperms, and seed plants, are known from Early Devonian fossils. Lycopsids experienced their first evolutionary radiation during the Devonian period. Early Devonian plant communities were generally similar regardless of what landmass they inhabited, although zosterophyllopsids displayed high levels of endemism.
In the Middle Devonian, euphyllophytes continued to increase in diversity. The first true forest environments featuring trees exceeding eight metres in height emerged by the Middle Devonian, with the earliest known fossil forest dating to the Eifelian. The oldest known trees were members of the clade Cladoxylopsida. Devonian swamp forests were dominated by giant horsetails (Equisetales), clubmosses, ancestral ferns (pteridophytes), and large lycophyte vascular plants such as Lepidodendrales, referred to as scale trees for the appearance of scales on their photosynthetic trunks. These lycophytes, which could grow up to 40 metres high, grew in great numbers around swamps along with tracheophytes. Seed ferns and true leaf-bearing plants such as progymnosperms also appeared at this time and became dominant in many habitats, particularly archeopteridaleans, which were likely related to conifers. Pseudosporochnaleans (morphologically similar to palms and tree ferns) likewise experienced a similar rise to dominance. Archeopteridaleans had likely developed extensive root systems, making them resistant to drought, and meaning they had a more significant impact on Devonian soil environments than pseudosporochnaleans.
The Late Devonian saw the most rapid land plant diversification of the Devonian, largely owing to the rapid radiation of pteridophytes and progymnosperms. Cladoxylopsids continued to dominate forest ecosystems during the early Late Devonian. During the latest Devonian, the first true spermatophytes appeared, evolving as a sister group to archaeopteridaleans or to progymnosperms as a whole.
Most flora in Devonian coal swamps would have seemed alien in appearance when compared with modern flora, such as giant horsetails which could grow up to 30 m in height. Devonian ancestral plants of modern plants that may have been very similar in appearance are ferns (Polypodiopsida), although many of them are thought to have been epiphytes rather than grounded plants. True gymnosperms like ginkgos (Ginkgophyta) and cycads (Cycadophyta) would appear slightly after the Devonian in the Carboniferous.
Vascular plant lineages of sphenoids, fern, progymnosperms, and seed plants evolved laminated leaves during the Devonian. Plants that possessed true leaves appeared during the Devonian, though they may have many independent origins with parallel trajectories of leaf morphologies. Morphological evidence to support this diversification theory appears in the Late Devonian or Early Carboniferous when compared with modern leaf morphologies. The marginal meristem also evolved in a parallel fashion through a similar process of modified structures around this time period. In a 1994 study by Richard M Bateman and William A. Dimechele of the evolutionary history of heterospory in the plant kingdom, researchers found evidence of 11 origins of heterospory events that had occurred independently in the Devonian within Zosterophyllopsida, Sphenopsida, Progymnospermopsida. The effect of this heterospory was that it presented a primary evolutionary advantage for these plants in colonizing land. The simultaneous colonization of dry land and increase in plant body size that many lineages underwent during this time was likely facilitated by another parallel development: the replacement of the ancestral central cylinder of xylem with more elongate, complex xylem strand shapes that would have made the plant body more resistant to the spread of drought-induced embolism. Tracheids, tapered cells that make up the xylem of vascular plants, first appear in the fossil record during the Early Devonian. Woody stems evolved during the Devonian as well, with the first evidence of them dating back to the Early Devonian. Evidence of root structures appears for the first time during the Late Silurian. Further appearances of roots in the fossil record are found in Early Devonian lycophytes, and it has been suggested that the development of roots was an adaptation for maximising water acquisition in response to the increase in aridity over the course of the Silurian and Devonian. The Early Devonian also saw the appearance of complex subterranean rhizome networks.
Effect on atmosphere, soil, and climate
Deep-rooted vascular plants had drastic impacts upon soil, atmosphere, and oceanic oxygen composition. The Devonian Plant Hypothesis is an explanation about these effects upon biogeomorphic ecosystems of climate and marine environments. A climate/carbon/vegetation model could explain the effects of plant colonization during the Devonian. Expansion of terrestrial Devonian flora modified soil properties, increasing silicate weathering by way of rhizosphere development as evidenced by pedogenic carbonates. This caused atmospheric levels to fall from around 6300 to 2100 ppmv, although it also drastically reduced the albedo of much of Earth's land surface, retarding the cooling effects of this greenhouse gas drawdown. The biological sequestration of so much carbon dioxide resulted in the beginning of the Late Palaeozoic Ice Age at the terminus of the Devonian, together with the tectonic uplift of the continent Gondwana. However, an alternative hypothesis holds that land plant evolution actually decreased silicate weathering rates, instead causing a drop in atmospheric carbon dioxide levels through elevated organic carbon burial brought about by the formation of wetlands. Some palaeoclimatic simulations have found that depending on the circumstances, the spread of plants could temporarily increase pCO2 by promoting regolith growth that would hinder the ability of water containing dissolved carbon dioxide to percolate into bedrock.
Oxygen levels rose as a direct result of plant expansion. With increased oxygenation came increased fire activity. Earth's atmosphere first became sufficiently high in oxygen to produce wildfires in the Pridoli, when the first charcoal evidence of wildfires is recorded. For most of the Early and Middle Devonian, the atmosphere was insufficiently oxygenated to enable significant fire activity. By the late Famennian, however, oxygen levels were high enough to enable wildfires to occur with regularity and on large scales, something which had not been previously possible due to the paucity of atmospheric oxygen.
The rise of trees and forests caused greater amounts of fine sediment particles to be retained on alluvial plains, increasing the complexity of meandering and braided fluvial systems. The greater complexity of terrestrial habitats facilitated the colonisation of the land by arthropods. Additionally, the increased weathering of phosphates and quantity of terrestrial humic matter increased nutrient levels in freshwater lakes, facilitating their colonisation by freshwater vertebrates. From these lakes, vertebrates would later follow arthropods in their conquest of the land.
The Devonian explosion had global consequences on oceanic nutrient content and sediment cycling, which had led to the Devonian mass extinction. The expansion of trees in the Late Devonian drastically increased biological weathering rates and the consequent riverine input of nutrients into the ocean. The altering of soil composition created anoxic sedimentation (or black shales), oceanic acidification, and global climate changes. This led to harsh living conditions for oceanic and terrestrial life.
The increase in terrestrial plant matter in swamplands explains the deposits of coal and oil that would later characterize the Carboniferous.
References
Silurian life
Devonian life
Evolution of plants | Silurian-Devonian Terrestrial Revolution | [
"Biology"
] | 2,792 | [
"Evolution of plants",
"Plants"
] |
63,520,876 | https://en.wikipedia.org/wiki/Nucleus%20estate%20and%20smallholder | Nucleus estate and smallholder (NES) is a farming system for commodity crops, often oil palm, practised in different world regions. It is most famous today for its application in the palm oil sector in Indonesia. The nucleus is the part of such a plantation that is under concession and management of the company, while another part of the plantation is operated by smallholders typically on their own land but planted by the company. NES farming is a particular form of contract farming.
Origins
The system was first implemented by Commonwealth Development Corporation in the 1950s in various African countries.
System
Smallholders work on their own farms usually organized in farmers' cooperatives and are contractually bound to the company. In Indonesia the price for fresh fruit bunches (FFB) in this scheme is set by the government.
The motivation for this kind of organizational and contractual arrangement is mainly that the initial investments to establish a plantation is considerable. Clearing land, building roads, and planting trees on sizeable areas requires not only elevated economic power but also technical skills. This part, therefore, is in the company's responsibility while the costs are later deducted from the payments made to the farmers.
Smallholders can benefit from the arrangement through technological transfers. Not only in the establishment of the plantation does the company play an important role. Also during operations, the company usually provides inputs such as fertilizer and pesticides to the smallholders. Often smallholders have additional independent oil palm farms where they can apply their newly acquired skills.
Country cases
Indonesia
History
The scheme has a long history in Indonesia, where it is commonly known as Inti-Plasma farming, Inti being the nucleus and plasma the smallholdings. It has been implemented in different ways since 1978. The first model was called PIR Lokal (Perkebunan Inti Rakyat Lokal) and was designed for local populations.
In later forms, NES was designed to settle transmigrants on the so called outer islands of Indonesia (i.e. outside of Java and Madura). This form of inti-plasma is called PIR Trans which stands for Perkebunan Inti Rakyat Transmigrasi, i.e. Nucleus Estate Smallholders Project for Transmigrants. Construction of health treatment facilities and public facilities such as roads, schools, houses of worship, clinics, and other projects were at times part of the PIR scheme.
Another, more recent form of the system, started in the 1990s and is called KKPA. It stands for Kredit Koperasi Primer Anggota, i.e. Credit for Cooperative Primary Members and is not attached to the transmigration program.
Recently, in the wake of decentralization and neo-liberal reforms, the kemitraan (partnership) scheme is shifting away from NES mechanics. Smallholders typically do no longer work on their land but receive dividends from their plantation part. This has shown to be very disadvantageous for the 'smallholders' involved in comparison with early days PIR schemes.
Cultural issues
A significant difference in how transmigrants and indigenous populations were treated is in how their own land was considered. Part of the transmigration program was to give resettled families two to four hectares of land for their own cultivation. However, indigenous populations willing to participate in such a scheme, had to give away parts of their land to become both inti and plasma oil palm farms. Such arrangements depend on the individual negotiation between village communities and oil palm companies and most commonly result in deals wherein 80% of the land becomes core plantation (inti) and 20% plasma.
Prevalence
In 2013, smallholders (not only plasma) were farming around 3.5 million ha of oil palm plantations or 39.5 percent of the plantation areas at that time.
Malaysia
Oil palm and rubber production schemes in Malaysia are no NES schemes, strictly speaking. Nevertheless they show similarities. These are managed smallholder schemes and joint-venture schemes. FELDA, the Malaysian Federal Land Development Authority, implemented settlements with managed smallholders. These do not have a nucleus but are strictly controlled by the FELDA management. FELCRA and SALCRA, the Federal and the Sarawak Land Consolidation and Rehabilitation Authorities followed similar approaches, yet focussing on local populations, not on resettlements.
Ghana
Having a long history of smallholders producing palm oil for domestic consumption (cooking oil, soap etc.), in the 2000s it started implementing nucleus estate and smallholder schemes. However, independent smallholders continue to produce the vast majority of palm oil in the West African nation.
See also
Palm oil production in Indonesia
References
Agriculture in Indonesia
Agricultural economics
Intensive farming
1950s introductions | Nucleus estate and smallholder | [
"Chemistry"
] | 942 | [
"Eutrophication",
"Intensive farming"
] |
63,523,688 | https://en.wikipedia.org/wiki/Italian%20Medicines%20Agency | The Italian Medicines Agency (Agenzia italiana del farmaco, AIFA) is the public institution responsible for the regulatory activity of pharmaceuticals in Italy.
See also
European Medicines Agency
Istituto Superiore di Sanità
External links
Medical and health organisations based in Italy
National agencies for drug regulation
Drugs in Italy
Regulators of biotechnology products
Regulation in Italy | Italian Medicines Agency | [
"Chemistry",
"Biology"
] | 69 | [
"Pharmacology",
"Biotechnology products",
"Regulation of biotechnologies",
"National agencies for drug regulation",
"Drug safety",
"Medicinal chemistry stubs",
"Regulators of biotechnology products",
"Pharmacology stubs"
] |
63,525,188 | https://en.wikipedia.org/wiki/Inga%20Berre | Inga Berre (born 31 July 1978) is a Norwegian applied mathematician who studies numerical methods for the partial differential equations used to model fractured geothermal systems and porous media more generally. She is a professor in the department of mathematics at the University of Bergen, a scientific advisor to the Chr. Michelsen Institute in Bergen, and a leading researcher on geothermal energy in Norway.
Education and career
Berre earned a candidate degree in mathematics from the University of Bergen in 2001, and completed a doctorate (Dr. Sci.) in 2005. Her dissertation, Fast simulation of transport and adaptive permeability estimation in porous media, was jointly supervised by Helge Dahle, Knut-Andreas Lie, Trond Mannseth, and Kenneth Hvistendahl Karlsen.
She joined the University of Bergen faculty as an associate professor in 2006, and was promoted to full professor in 2013. In 2018 she became chair of the Joint Programme Geothermal of the European Energy Research Alliance.
Recognition
Berre is a member of the Norwegian Academy of Technological Sciences, elected in 2017. In 2021 she was elected Council Members-at-Large for SIAM for a term running January 1, 2022 - December 31, 2024.
References
External links
Making Research Matter - interview with Inga Berre, University of Bergen, 9 September 2020
Interview with Inga Berre, Carina Bringedal, Univ. of Stuttgart, 11 November 2019
1978 births
Living people
Norwegian mathematicians
Norwegian women mathematicians
Applied mathematicians
University of Bergen alumni
Academic staff of the University of Bergen
Members of the Norwegian Academy of Technological Sciences | Inga Berre | [
"Mathematics"
] | 322 | [
"Applied mathematics",
"Applied mathematicians"
] |
63,525,792 | https://en.wikipedia.org/wiki/Epidemiology%20of%20hepatitis%20D | The epidemiology of hepatitis D occurs worldwide. Although the figures are disputed, a recent systematic review suggests that up to 60 million individuals could be infected. The major victims are the carriers of the hepatitis B surface antigen (HBsAg), who become superinfected by the HDV, and intravenous drug users who are the group at highest risk. The infection usually results in liver damage (hepatitis D); this is most often a chronic and severe hepatitis rapidly conducive to cirrhosis.
Detection
Infection with the HDV is recognized by the finding of the homologous antibody (anti-HD) in serum. Testing for the viral genome (HDV RNA) is limited. In 2013, the 1st World Health Organization International Standard of HDV RNA for nucleic acid amplification techniques (NAT)-based assays was developed.
The underlying HBV infection required to support the HDV is critical to determine the outcome of hepatitis D. In simultaneous coinfection with the HBV, the HDV is rescued by the partner HBV with which it shares the HBsAg coat; in superinfections of HBsAg carriers, it is rescued by the foreign HBV of the carrier which provides the HBsAg coat for the assembly of the HD virion. Coinfections run an acute course; expression of the HDV is accompanied by a weak and transient antibody response and is ephemeral.
In superinfections, the chronic HBV infection and HBsAg state indefinitely sustains the replication of the HDV, resulting in a persistent anti-HD response that can be detected in any random blood sample over time; therefore, carriers of the HBsAg are the only reliable source of epidemiological information. However, HDV infections are highly pathogenic and induce the development of liver cirrhosis in approximately 70% of cases within five to ten years, with the risk of cirrhosis threefold higher in HDV-HBV co-infected than in HBV mono-infected patients. As the probability of finding anti-HD throughout the clinical spectrum of HBV liver disorders increases in parallel with the severity of the liver disease. Patients with advanced HBV liver disease are the most suitable category of HBV carriers to determine the epidemiology and real health burden of HDV.
By region
Low HDV endemicity areas are North America, North Europe and Australia, where it is virtually confined to intravenous drug users and immigrants from infected areas. High endemicity areas remain in the Amazon basin and low income regions of Asia and Africa; outbreaks and fulminant hepatitis D were reported in the past in the Brazilian and Peruvian Amazon, the Central African Republic, the Himalayan foothills and after the year 2000, in Samara (Russia), Greenland and Mongolia.
By controlling HBV infection, the implementation of hepatitis B vaccination in the industrialized world has led to a marked reduction of HDV particularly in Southern Europe and Taiwan. In Italy, HDV diminished among HBV liver disorders from 24.6% in 1983 to 8% in 1997. The residual prevalence of chronic hepatitis D in HBV liver diseases in Western Europe is, as of 2010, between 4.5% and 10%, with immigrants from endemic HDV areas accounting for the larger proportion of cases.
The risk of HDV has not significantly changed in recent years in countries of the world where HBV remains uncontrolled. In Asia up to 2015, the highest prevalences of chronic HDV liver disease were reported in Pakistan, Iran, Tajikistan, and Mongolia; a 2019 study has shown that over 80% of HBsAg cirrhosis cases in Uzbekistan are associated with HDV infection. From partial and scattered information the prevalence in China, and India appears to be low.
In many countries of Africa, the role of hepatitis D is unknown for lack of testing. The highest rates of HDV infection were reported in sub-Saharan Africa, with the finding of anti-HD in over 30% and 50% of the general HBsAg population of Gabon and Cameroon, respectively, and in over 50% of the HBsAg cirrhotics in the Central African Republic (Figure 1). Lesser but consistent antibody rates (from 20% to 43%, with a mean of 24%) were reported in HBsAg liver disease in Tunisia, Mauritania, Senegal, Nigeria, Somalia and upper Egypt. Low prevalences of 2.5% and 12.7% have been reported in HBV disease carriers in Libya and Ethiopia.
Low prevalence of 0 to 8% has also been reported from Morocco, Algeria, Burkina-Faso, Benin, Mali, Sudan, South Africa and Mozambique; however, they were derived from asymptomatic HBsAg-carriers at low risk of HDV, collected at blood banks and in pregnancy clinics.
References
Viruses | Epidemiology of hepatitis D | [
"Biology"
] | 1,012 | [
"Viruses",
"Tree of life (biology)",
"Microorganisms"
] |
63,525,969 | https://en.wikipedia.org/wiki/Hygrophorus%20flavescens | Hygrophorus flavescens is an edible mushroom of the genus Hygrophorus found in the Pacific Northwest, eastern North America, and Texas. It is similar to Hygrophorus chlorophanus, which has a sticky coating.
The fruiting body reaches up to wide and tall.
References
Edible fungi
flavescens
Fungi described in 1906
Fungi of the United States
Fungi without expected TNC conservation status
Fungus species | Hygrophorus flavescens | [
"Biology"
] | 94 | [
"Fungi",
"Fungus species"
] |
63,526,245 | https://en.wikipedia.org/wiki/Nano-Structures%20%26%20Nano-Objects | Nano-Structures & Nano-Objects is an interdisciplinary peer-reviewed scientific journal devoted to all aspects of the synthesis and properties of the nanotechnology. The journal focuses on novel architecture at the nanolevel with an emphasis on new synthesis and characterization methods. The journal focused on objects rather than on their application. However, various novel applications (nano-electronics, energy conversion, catalysis, drug delivery and nano-medicine) using Nanostructures and Nano-objects are considered in this journal.
The journal is published by Elsevier and publishes four volumes per year.
Editor-in-Chief
Sabu Thomas is the current Editor-in-Chief of the Nano-Structures & Nano-Objects.
Indexing
The journal is indexed in the Scopus, INSPEC, and PubMed.
References
Nanotechnology journals | Nano-Structures & Nano-Objects | [
"Materials_science"
] | 168 | [
"Materials science stubs",
"Nanotechnology journals",
"Materials science journals",
"Materials science journal stubs",
"Nanotechnology stubs",
"Nanotechnology"
] |
63,526,503 | https://en.wikipedia.org/wiki/PDE-constrained%20optimization | PDE-constrained optimization is a subset of mathematical optimization where at least one of the constraints may be expressed as a partial differential equation. Typical domains where these problems arise include aerodynamics, computational fluid dynamics, image segmentation, and inverse problems. A standard formulation of PDE-constrained optimization encountered in a number of disciplines is given by:where is the control variable and is the squared Euclidean norm and is not a norm itself. Closed-form solutions are generally unavailable for PDE-constrained optimization problems, necessitating the development of numerical methods.
Applications
Aerodynamic shape optimization
Drug delivery
Mathematical finance
Epidemiology
Optimal control of bacterial chemotaxis system
The following example comes from p. 20-21 of Pearson. Chemotaxis is the movement of an organism in response to an external chemical stimulus. One problem of particular interest is in managing the spatial dynamics of bacteria that are subject to chemotaxis to achieve some desired result. For a cell density and concentration density of a chemoattractant, it is possible to formulate a boundary control problem:where is the ideal cell density, is the ideal concentration density, and is the control variable. This objective function is subject to the dynamics:where is the Laplace operator.
See also
Multiphysics
Shape optimization
SU2 code
References
Further reading
Antil, Harbir; Kouri, Drew. P; Lacasse, Martin-D.; Ridzal, Denis (2018). Frontiers in PDE-Constrained Optimization. The IMA Volumes in Mathematics and its Applications, Springer. .
Tröltzsch, Fredi (2010). Optimal Control of Partial Differential Equations: Theory, Methods, and Applications. Graduate Studies in Mathematics, American Mathematical Society. .
External links
A Brief Introduction to PDE Constrained Optimization
PDE Constrained Optimization
Optimal solvers for PDE-Constrained Optimization
Model Problems in PDE-Constrained Optimization
Mathematical optimization
Optimal control
Partial differential equations | PDE-constrained optimization | [
"Mathematics"
] | 389 | [
"Mathematical optimization",
"Mathematical analysis"
] |
63,527,123 | https://en.wikipedia.org/wiki/Time%20in%20Estonia | Estonia uses Eastern European Time (EET) (UTC+02:00) during winter, and Eastern European Summer Time (EEST) (UTC+03:00) during summer. Estonia has observed daylight saving time since 1981. However, it wasn't used in 1989-1996 and 2000–2002.
Before autumn 1940, Eastern European Time was used in Estonia. After incorporation into Soviet Union, Moscow Time was imposed on. Moscow Time was used until 26 March 1989.
References
External links
Current Local Time in Tallinn
Estonia
Science and technology in Estonia
Geography of Estonia | Time in Estonia | [
"Physics"
] | 115 | [
"Spacetime",
"Physical quantities",
"Time",
"Time by country"
] |
63,527,682 | https://en.wikipedia.org/wiki/Hinokinin | Hinokinin is a dibenzylbutyrolactone lignan, derived from various species of plants. It is a potential antichagonistic agent. In vitro, it has been shown to have potential neuroprotective effects as well as anti-inflammatory, anti-tumor, antiviral and antifungal properties.
Hinokinin was isolated for the first time by Yoshiki and Ishiguro in 1933 from hinoki wood.
Chemical properties
Hinokinin is a colourless crystalline compound.
It can be isolated from various species of Chamaecyparis, Zanthoxylum, Phyllanthus, Aristolochia, Piper, Virola, Linum and Bursera. It is also synthesised from pinoresinol.
Biological effects
Cytotoxic actions
Hinokinin has shown to induce apoptosis and promote antitumor actions on various cancer cell lines in vitro.
Anti-inflammatory actions
Hinokinin has been shown to inhibit the generation of superoxide molecules by neutrophils and also decreases elastase secretion from neutrophils. It has also shown to reduce LPS induced nitric oxide production from macrophages.The anti-inflammatory property of hinokinin is mediated by the NF-kB signalling mechanism.
Anti-parasitic actions
Hinokinin has been shown to be an antitrypanosomal agent. Its use as a treatment for trypanosomiasis is still being researched.
Anti-viral actions
It has shown significant antiviral activity against human hepatitis B virus, HIV and SARS-CoV.
See also
Cubebin
References
Lignans
Antiviral drugs
Severe acute respiratory syndrome
Anti-inflammatory agents
Antifungals
Benzodioxoles
Lactones | Hinokinin | [
"Biology"
] | 373 | [
"Antiviral drugs",
"Biocides"
] |
63,528,473 | https://en.wikipedia.org/wiki/Trumpler%2027 | Trumpler 27 is a possible open cluster in the southern constellation Scorpius. If it exists, it is a few thousand light-years away from the Sun, with estimates ranging from 3,900 light-years (1,210 kiloparsecs) to 6,800 light-years (2,100 kiloparsecs) The name refers to Robert Julius Trumpler's catalog of open clusters, published in 1930.
It was originally thought to be young open cluster in the outer edge of the Sagittarius Arm, still surrounded by interstellar matter. The light from the stars is heavily extinguished and reddened by intervening interstellar dust. The light coming from the stars is also significantly polarized. However, a close study in 2012 could not confirm whether the stars truly form a cluster, or if they are a close alignment of bright stars.
Several member stars have been studied in closer detail. Star #1 of Trumpler 27 is CD−33°12241, a red supergiant star with a spectral type of M0Ia. Stars #28 and #105 are Wolf-Rayet stars. Star #27, a blue giant star with a spectral type of O8III((f)), may be one of the most luminous stars known, with a bolometric magnitude of −10.5. Star #102 is known as V925 Scorpii or HD 159378, and is a rare yellow supergiant star.
See also
List of most massive stars
References
Open clusters
Scorpius | Trumpler 27 | [
"Astronomy"
] | 320 | [
"Scorpius",
"Constellations"
] |
63,529,602 | https://en.wikipedia.org/wiki/International%20Association%20for%20the%20Physical%20Sciences%20of%20the%20Oceans | International Association for the Physical Sciences of the Oceans (IAPSO) is one of eight associations of the International Union of Geodesy and Geophysics (IUGG), constituted within the International Science Council (ISC). It was founded in 1919 as an oceanographic section of the IUGG and renamed an association in 1931. IAPSO is the primary body responsible for maintaining and improving oceanographic standards and practices. The President of IAPSO is Dr. Hans van Haren.
IAPSO’s Goal and Objectives
IAPSO’s prime goal is "promoting the study of scientific problems relating to the oceans and the interactions taking places at the sea floor, coastal, and atmospheric boundaries insofar as such research is conducted by the use of mathematics, physics, and chemistry." This goal is addressed through four objectives:
Organization, sponsorship, and co-sponsorship of formal and informal international events to facilitate communication of ocean scientists throughout the world;
Establishment of commissions, sub-committees, and organization of commensurate workshops to support and coordinate new and advanced international research activities;
Provision of services needed to conduct the physical sciences of the oceans;
Publishing proceedings of the conducted events and fundamental references on the current state-of-the art and knowledge of physical sciences of the oceans.
Awards and honors
Prince Albert I Medal
The IAPSO Prince Albert I Medal is provided by the Foundation Rainier III of Monaco every two years to scientists for outstanding contributions to the physical sciences of the oceans. In 2023 the recipient of the IAPSO Prince Albert I Medal was Prof. John A. Church, Emeritus Professor at the University of New South Wales, Australia, for his outstanding contributions to sea level research and related new insights into climate change.
Eugene LaFond Medal
The Eugene LaFond Medal is awarded to ocean scientists from developing countries for presentation (poster or oral) in a IAPSO-sponsored or co-sponsored symposium at the IUGG or IAPSO assemblies. In 2023 The Eugene LaFond Medal 2023 was awarded at the IUGG General Assembly in Berlin, July 11 - 20, 2023 to Dr. Helenice Vital from Brazil.
IAPSO Early Career Scientist Medal
The award is granted every two years to early career scientists for outstanding research in the physical and chemical oceanography and for their cooperation in international research. In 2023, Dr. Malte F. Stuecker, from the Department of Oceanography & International Pacific Research Center, University of Hawai‘i at Manoa, Honolulu, USA, became the recipient of the IAPSO Early Career Scientist medal in physical oceanography.
References
Scientific organizations established in 1919
Members of the International Council for Science
Geographic societies
Oceanography
Earth sciences societies | International Association for the Physical Sciences of the Oceans | [
"Physics",
"Environmental_science"
] | 556 | [
"Oceanography",
"Hydrology",
"Applied and interdisciplinary physics"
] |
63,530,080 | https://en.wikipedia.org/wiki/River%20City%20Science%20Academy | River City Science Academy (RCSA) is Charter School in Jacksonville, Florida, part of the Duval County School District. The school currently has six locations in Jacksonville and is known for its focus on STEM curriculum.
School grades
RCSA Middle-High currently has a "A" as of 2019 on the Florida School Accountability Grading Scale.
RCSA Elementary currently has a "A" as of 2019 on the Florida School Accountability Grading Scale.
RCSA Mandarin currently has a "A" as of 2019 on the Florida School Accountability Grading Scale.
RCSA Innovation currently has a "B" as of 2019 on the Florida School Accountability Grading Scale.
Academic programs
RCSA offers degree programs to its students including the gifted program, dual enrollment classes through Florida State College at Jacksonville and University of North Florida, the AP Capstone program, and multiple CTE electives, and debate. The debate team that they have is one that was created three years ago. They had multiple placements in the FCDI state debate championship, for both their middle and high school teams.
Notable achievements
First public charter school in Duval County and surrounding areas to be granted an "A" grade by Florida Department of Education
In 2016, RCSA Elementary took home 1st place in the Science Olympiad State Competition.
RCSA is recognized as a Florida service-learning leader school by the Florida Department of Education
In 2018, RCSA Middle-High's Science Olympiad Team won first place in the state of Florida and competed at the National Competition in Colorado. In 2019, the team won second place in the state of Florida and competed at the National Competition in New York.
In 2019, RCSA Mandarin's SeaPerch Team won first place in the state of Florida.
First public charter school to be granted high-performing status from the Florida Department of Education
Recipient of Five Star School Award
Recipient of School of Excellence Award
In 2023, RCSA SeaPerch Team Aquarius earned first place in both the obstacle course and mission course, making them the overall high school stock class Champions in the RoboNation International SeaPerch Challenge held at the University of Maryland.
In 2024, for the second year in a row RCSA SeaPerch Team Aquarius earned first place in the mission course and were the overall high school stock class Champions in the RoboNation International SeaPerch Challenge held at the University of Maryland.
Athletics
RCSA Middle-High students can currently participate in volleyball, basketball, and cheerleading. Middle schooler's at RCSA Innovation can participate in volleyball and basketball, and track and field. The teams are part of the Florida High School Athletic Association.
Campuses
River City Science Academy Elementary
River City Science Academy Middle-High
River City Science Academy Innovation
River City Science Academy Mandarin
River City Science Academy Intracoastal
River City Science Academy Southeast
References
Charter schools in Florida
2007 establishments in Florida
Schools in Duval County, Florida
Science and technology studies | River City Science Academy | [
"Technology"
] | 582 | [
"Science and technology studies"
] |
63,530,168 | https://en.wikipedia.org/wiki/Obelus | An obelus (plural: obeluses or obeli) is a term in codicology and latterly in typography that refers to a historical annotation mark which has resolved to three modern meanings:
Division sign
Dagger
Commercial minus sign (limited geographical area of use)
The word "obelus" comes from (obelós), the Ancient Greek word for a sharpened stick, spit, or pointed pillar. This is the same root as that of the word 'obelisk'.
In mathematics, the first symbol is mainly used in Anglophone countries to represent the mathematical operation of division and is called an obelus. In editing texts, the second symbol, also called a dagger mark is used to indicate erroneous or dubious content; or as a reference mark or footnote indicator. It also has other uses in a variety of specialist contexts.
Use in text annotation
The modern dagger symbol originated from a variant of the obelus, originally depicted by a plain line , or a line with one or two dots . It represented an iron roasting spit, a dart, or the sharp end of a javelin, symbolizing the skewering or cutting out of dubious matter.
Originally, one of these marks (or a plain line) was used in ancient manuscripts to mark passages that were suspected of being corrupted or spurious; the practice of adding such marginal notes became known as obelism. The dagger symbol , also called an obelisk, is derived from the obelus, and continues to be used for this purpose.
The obelus is believed to have been invented by the Homeric scholar Zenodotus, as one of a system of editorial symbols. They marked questionable or corrupt words or passages in manuscripts of the Homeric epics. The system was further refined by his student Aristophanes of Byzantium, who first introduced the asterisk and used a symbol resembling a for an obelus; and finally by Aristophanes' student, in turn, Aristarchus, from whom they earned the name of "Aristarchian symbols".
In some commercial and financial documents, especially in Germany and Scandinavia, a variant () is used in the margins of letters to indicate an enclosure, where the upper point is sometimes replaced with the corresponding number. In Finland, the obelus (or a slight variant, ) is used as a symbol for a correct response (alongside the check mark, , which is used for an incorrect response).
In the 7.0 release of Unicode, was one of a group of "Ancient Greek textual symbols" that were added to the specification (in the block Supplemental Punctuation).
In mathematics
The form of the obelus as a horizontal line with a dot above and a dot below, , was first used as a symbol for division by the Swiss mathematician Johann Rahn in his book Teutsche Algebra in 1659. This gave rise to the modern mathematical symbol , used in anglophone countries as a division sign. This usage, though widespread in Anglophone countries, is neither universal nor recommended: the ISO 80000-2 standard for mathematical notation recommends only the solidus or fraction bar for division, or the colon for ratios; it says that "should not be used" for division. The ambiguity of mathematical expressions that involve the obelus and implicit multiplication has become a subject of Internet memes.
This form of the obelus was also occasionally used as a mathematical symbol for subtraction in Northern Europe; such usage continued in some parts of Europe (including Norway and, until fairly recently, Denmark). In Italy, Poland and Russia, this notation is sometimes used in engineering to denote a range of values.
In some commercial and financial documents, especially in Germany and Scandinavia, another form of the obelus the commercial minus sign is used to signify a negative remainder of a division operation.
See also
() used for obelism.
List of typographical symbols and punctuation marks
References
Typographical symbols | Obelus | [
"Mathematics"
] | 810 | [
"Symbols",
"Typographical symbols"
] |
63,530,577 | https://en.wikipedia.org/wiki/Nitensidine%20D | Nitensidine D is a toxic alkaloid natural product that was isolated from the leaves of the South American legume Pterogyne nitens. It is also hypothesized to be a possible intermediate in the still unknown, seemingly monoterpene based, terrestrial biosynthetic pathway for tetrodotoxin.
See also
Galegine
References
Guanidine alkaloids
Plant toxins | Nitensidine D | [
"Chemistry"
] | 87 | [
"Alkaloids by chemical classification",
"Guanidine alkaloids",
"Chemical ecology",
"Plant toxins"
] |
76,583,256 | https://en.wikipedia.org/wiki/Ardalan%20Vahidi | Ardalan Vahidi is an Iranian-American mechanical engineer, specializing in optimal control and estimation, energy-efficient mobility, connected and automated vehicles, electrified transportation, and human bioenergetics during exercise. He is known for his pioneering contributions to methods that significantly enhance the energy efficiency of vehicles, particularly connected and automated vehicles and hybrid electric vehicles. Vahidi has collaborated with major manufacturers such as BMW, Ford, and Cummins, and has led numerous federally sponsored projects, culminating in successful on-road demonstrations. His work has been instrumental in achieving up to 30% energy savings in vehicles through innovative algorithms and real-time optimization techniques.
Early life and education
Ardalan Vahidi completed his Ph.D. at the University of Michigan, Ann Arbor, in 2005. Prior to that, he earned his M.S. degree in Transportation Safety from George Washington University in 2001, following B.S. and M.S. degrees in Civil Engineering from Sharif University in 1996 and 1998 respectively.
Career
Vahidi joined Clemson University's Department of Mechanical Engineering in 2005, where he currently serves as a professor. His research focuses on developing advanced control and estimation algorithms to improve the efficiency and performance of various transportation systems. He has been particularly active in the areas of energy-efficient driving, vehicle connectivity, and autonomous driving technologies.
Research contributions
Throughout his career, Vahidi has made significant contributions to the field of energy-efficient mobility. His research leverages vehicle connectivity to anticipate upcoming energy demands and vehicle autonomy to provide precise control over vehicle motion. By employing real-time optimization techniques, his algorithms can devise motion plans that preserve energy, leading to reduced fuel consumption and emissions. Examples of his work include minimizing idling at urban intersections and optimizing driving behavior in stop-and-go traffic, which not only benefit individual vehicles but also contribute to traffic harmonization and overall energy efficiency.
Awards and recognition
In 2024, he was elected as an IEEE Fellow, one of the highest honors bestowed by the Institute of Electrical and Electronics Engineers. This recognition underscores his exceptional achievements in the control of connected, automated, and hybrid vehicles, as well as his commitment to advancing energy-efficient mobility solutions. He was also promoted to Fellow in The American Society of Mechanical Engineers (ASME) in 2020.
References
Fellows of the IEEE
Iranian scholars
Clemson University faculty
Year of birth missing (living people)
Living people
Mechanical engineers | Ardalan Vahidi | [
"Engineering"
] | 495 | [
"Mechanical engineers",
"Mechanical engineering"
] |
76,583,678 | https://en.wikipedia.org/wiki/Solar%20System%20belts | Solar System belts are asteroid and comet belts that orbit the Sun in the Solar System in interplanetary space. The Solar System belts' size and placement are mostly a result of the Solar System having four giant planets: Jupiter, Saturn, Uranus and Neptune far from the sun. The giant planets must be in the correct place, not too close or too far from the sun for a system to have Solar System belts.
Formation
The Solar System belts were formed in the formation and evolution of the Solar System. The Grand tack hypothesis is a model of the unique placement of the giant planets and the Solar System belts. Most giant planets found outside our Solar System, exoplanets, are inside the snow line, and are called Hot Jupiters. Thus in normal planetary systems giant planets form beyond snow line and then migrated towards the star. A small percent of giant planets migrate far from the star. In both types of migrations, the Solar System belts are lost in these planetary migrations. The Grand tack hypothesis explains how in the Solar System giant planets migrated in unique way to form the Solar System belts and near circular orbit of planets around the Sun. The Solar System's belts are one key parameters for a Solar System that can support complex life, as circular orbits are a parameter needed for the Habitable zone for complex life.
Solar System belts
The asteroid and comet belts orbit the Sun from the inner rocky planets into outer parts of the Solar System, interstellar space. An astronomical unit, or AU, is the distance from Earth to the Sun, which is approximately 150 billion meters (93 million miles). Small Solar System objects are classified by their orbits:
Main Asteroid belt (main belt), between Mars and Jupiter, in near circular orbit, 2.2 to 3.2 AU
Hungaria asteroids, small group, 1.78 to 2.00 AU
Alinda asteroids, small group, 2.5 AU in elliptical orbits
Hilda asteroid small group just inside Jupiter, 4.0 AU
Kuiper belt large belt, 43 to 64.5 AU
Scattered disc small group, 21.5 to 215 AU
Sednoid (inner Oort cloud objects) small group of four or more, high elliptical orbits, 47.8 to 80 AU
Extreme trans-Neptunian objects 150 to 250 AU
Hills cloud a large hypothetical circumstellar disc
Planets
Solar System planets and dwarf planets listed for distances comparison to belts. The Solar System planets all orbit in near circular orbits.
Planets:
Mercury 0.39 AU
Venus 0.72 AU
Earth 1 AU
Mars 1.52 AU
Jupiter 5.2 AU
Saturn 9.54 AU
Uranus 19.2 AU
Neptune 30.06 AU
Dwarf planets:
Dwarf planets, other than Ceres, are plutoids that have elliptical orbits:
Ceres, 2.8 AU in the asteroid belt
Orcus 39.4 AU, Trans-Neptunian-Kuiper belt object
Pluto 39 AU, Kuiper belt (a planet until 2006)
Haumea 43 AU, Kuiper belt
Makemake 45.8 AU, Kuiper belt
Eris 95.6 AU, Kuiper belt
Gonggong Scattered disc object, 34 to 101 AU
Quaoar Kuiper belt object, 41.9 to 45.4 AU
Sedna 76 to 506 AU
See also
Near-Earth object
Planetary migration
Late Heavy Bombardment
List of gravitationally rounded objects of the Solar System
List of Solar System objects by size
Lists of geological features of the Solar System
List of Solar System extremes
Outline of the Solar System
References
External links
Expected Science Return of Spatially-Extended In-Situ Exploration at Small Solar System Bodies
Solar System
Planetary science
Space science | Solar System belts | [
"Astronomy"
] | 744 | [
"Outer space",
"Space science",
"Planetary science",
"Solar System",
"Astronomical sub-disciplines"
] |
76,585,640 | https://en.wikipedia.org/wiki/Maya%20Bhatia | Maya Bhatia was a Canadian biogeochemist known for her research in the Arctic, focusing on microbial ecology and biogeochemistry. Bhatia died during field work near Grise Fiord in 2023.
Early life and education
Bhatia was an alumna of the University of Alberta, where she received her bachelor's and master's degrees, contributing early to her field under the supervision of Martin Sharp and Julia Foght in the Departments of Earth and Atmospheric Sciences and Biological Sciences. She furthered her education in the MIT-WHOI Joint Program, graduating in February 2012 with a PhD, co-advised by Elizabeth Kujawinski and Sarah Das in the MG&G Department.
Career and research
As an associate professor at the University of Alberta and a CAIP Chair in Watershed Science, Bhatia's research spanned glaciers, ice sheets, and oceans. Her work focused on understanding the interactions between microbes and their environment, particularly in relation to carbon cycling and nutrient production, with implications for global climate change. In 2022, Dr. Maya Bhatia received the CNC/SCOR Early Career Ocean Scientist Award for her contributions to oceanography and biogeochemistry research in northern Canada, focusing on the impacts of climate change on the ocean and nutrient contributions from glaciers.
Death
Bhatia died while conducting field work in the High Arctic near Aujuittuq (Grise Fiord), Nunavut, on 16 August 2023. She was swept away after slipping and falling while collecting water from a supraglacial stream. Her student and the helicopter pilot were with her at the time but unable to reach her due to fast moving water.
References
Year of birth missing
2023 deaths
University of Alberta alumni
Women biochemists
Canadian biochemists
Massachusetts Institute of Technology alumni | Maya Bhatia | [
"Chemistry"
] | 374 | [
"Biochemists",
"Women biochemists"
] |
76,587,005 | https://en.wikipedia.org/wiki/Remethylation | Remethylation involves methylation that occurs in some biochemical cycles. Often methyl groups are not mobile when attached to nitrogen and sulfur, but the removal and reinstallation of methyl groups does occur with the assistance of certain enzymes.
Homocysteine-methionine interconversion
Remethylation is a major step in the conversion of homocysteine to the essential amino acid methionine. The remethylation process involves the enzyme methionine synthase (MS), which requires vitamin B12 as a cofactor, and also depends indirectly on folate and other B vitamins. A second pathway, which is usually restricted to liver and kidney in most mammals, involves betaine-homocysteine methyltransferase (BHMT) and requires trimethylglycine as a cofactor.
DNA processing and epigenetics
Remethylation also has a role in epigenetics and neuroplasticity. DNA methylation patterns are largely erased and then re-established (remethylated) between generations in mammals. Almost all of the methylations from the parents are erased, first during gametogenesis, and again in early embryogenesis, with demethylation and remethylation occurring each time. Demethylation in early embryogenesis occurs in the preimplantation period in two stages – initially in the zygote, then during the first few embryonic replication cycles of morula and blastula. A wave of methylation then takes place during the implantation stage of the embryo, with CpG islands protected from methylation. This results in global repression and allows housekeeping genes to be expressed in all cells. In the post-implantation stage, methylation patterns are stage- and tissue-specific, with changes that would define each individual cell type lasting stably over a long period.
References
Sulfur amino acids
Thiols
Non-proteinogenic amino acids | Remethylation | [
"Chemistry"
] | 403 | [
"Organic compounds",
"Thiols"
] |
76,588,063 | https://en.wikipedia.org/wiki/Gillian%20Bowser | Gillian Bowser is an American wildlife ecologist, research scientist, and associate professor at Colorado State University. Her work largely centers on climate change with focuses on pollinators and citizen science.
Early life and education
Bowser was born in New York to African-American film archivist Pearl Bowser and civil rights activist LeRoy Bowser. As a child, she was a member of Ranger Rick's Nature Club. She attended LaGuardia High School of the Arts as an art major, completing a degree in fine arts with a focus on medical illustration. She earned her B.S. from Northwestern University, her M.S. from the University of Vermont, and her Ph.D. from the University of Missouri.
Career
Bowser started working at Yellowstone National Park as a college student, where she eventually became a wildlife biologist. She was present during the fires in 1988. She also worked for the National Park Service in Grand Teton National Park, Joshua Tree National Park, Wrangell–St. Elias National Park and Preserve, and for the headquarters in Washington, D.C..
Bowser was a 2011–2012 American Association for the Advancement of Science Executive Branch Fellow at the United States Department of State and a 2022 AAAS Fellow of Science and Engineering. She was a 2014 Fulbright Specialist to Peru, during which she studied indicators of climate change at Huascarán National Park.
Bowser is an environmental assessment expert for the United Nations Environment Programme's Global Environmental Outlook and participated in the UN Framework Convention on Climate Change, and is a section leader for the U.S. Global Change Research Program's National Nature Assessment. She is currently an executive committee member of the International Union of Biological Sciences.
As a researcher, Bowser studied elk and bison in Yellowstone National Park, and pollinators in national parks around the world. Broadly, she focuses on how climate change affects pollinators and ecological indicators of climate change. She promotes citizen science as a tool to track ecological changes, particularly to understand the impacts of climate change in national parks and protected areas. She is an advocate for underrepresented minorities in STEM, and is a principal investigator of the National Science Foundation-funded Fieldwork Inspiring Expanded Leadership for Diversity (FIELD) project working to reduce barriers in geoscientific field activity.
Notable publications
Environment, U. N. (2019). Global environment outlook—GEO-6: healthy planet, healthy people. Nairobi. DOI 10.1017/9781108627146.
Cooper, C. B., Hawn, C. L., Larson, L. R., Parrish, J. K., Bowser, G., Cavalier, D., Dunn, R. R., Haklay, M. (Muki), Gupta, K. K., Jelks, N. O., Johnson, V. A., Katti, M., Leggett, Z., Wilson, O. R., & Wilson, S. (2021). Inclusion in citizen science: The conundrum of rebranding. Science, 372(6549), 1386–1388. https://doi.org/10.1126/science.abi6487
Shinbrot, X. A., Wilkins, K., Gretzel, U., & Bowser, G. (2019). Unlocking women’s sustainability leadership potential: Perceptions of contributions and challenges for women in sustainable development. World Development, 119, 120–132. https://doi.org/10.1016/j.worlddev.2019.03.009
Morales, N., Bisbee O’Connell, K., McNulty, S., Berkowitz, A., Bowser, G., Giamellaro, M., & Miriti, M. N. (2020). Promoting inclusion in ecological field experiences: Examining and overcoming barriers to a professional rite of passage. The Bulletin of the Ecological Society of America, 101(4), e01742. https://doi.org/10.1002/bes2.1742
References
Ecologists
African-American women academics
Northwestern University alumni
University of Vermont alumni
University of Missouri alumni
1960 births
Living people | Gillian Bowser | [
"Environmental_science"
] | 885 | [
"Ecologists",
"Environmental scientists"
] |
76,589,675 | https://en.wikipedia.org/wiki/Materialism%20controversy | The materialism controversy (German: ) was a debate in the mid-19th century regarding the implications for current worldviews of the natural sciences. In the 1840s, a new type of materialism was developed, influenced by the methodological advancements in biology and the decline of idealistic philosophy. This form of materialism aimed to explain humans in scientific terms. The controversy revolved around whether the findings of natural sciences were compatible with the concepts of an immaterial soul, a personal God and free will. Additionally, the debate focused on the epistemological requirements of a materialist/mechanist worldview.
In his "Physiologische Briefe" from 1846, the zoologist Carl Vogt explained that "thoughts have roughly the same relationship to the brain as bile has to the liver or urine to the kidneys." In 1854, the physiologist Rudolf Wagner criticised Vogt's polemical commitment to materialism in a speech to the Göttingen Naturalists' Assembly. Wagner argued that Christian faith and natural history were two largely independent spheres. The natural sciences could therefore contribute nothing to the questions of the existence of God, the immaterial soul or free will.
Wagner's attacks provoked equally sharp reactions from Vogt. The materialist point of view was also defended in the following years by the physiologist Jakob Moleschott and the doctor Ludwig Büchner, a brother of the well-known writer Georg Büchner. The materialists presented themselves as champions against philosophical, religious, and political reactionism. They set very different emphases but could count on broad support among the bourgeoisie. The promise of a scientific worldview became a defining element of the cultural conflicts in the late 19th and early 20th centuries.
Development of natural scientific materialism
Emancipation of biology
The rise of popular materialism was encouraged by a critique of romantic-idealistic natural philosophy, which became widespread after 1830 and had an equal influence on natural science, philosophy, and politics.
From the perspective of the history of science, the cell theory founded by Matthias Jacob Schleiden proved to be particularly influential. In his 1838 publication on phytogenesis, Schleiden declared the cell as the fundamental unit of all plants and identified the cell nucleus, which was discovered in 1831, as an essential factor in plant growth. The cellular theory of plant organism structure brought about a reorientation in botany. Before this, botany was primarily focused on macroscopic descriptions of forms. Schleiden's theory of plant structure was combined with a methodological critique of idealistic natural philosophy. The cell theory is based on empirically verifiable observations. This is because "one only knows as many facts about the objects of the physical natural sciences as they have observed themselves". The speculations of natural philosophers, on the other hand, were not based on strict observation. Therefore, all "forging of systems and theories had to be thrown" aside.
Schleiden's programme for a methodically renewed botany was extended to other biological disciplines in subsequent years. In 1839, Theodor Schwann published his Mikroskopische Untersuchungen über die Uebereinstimmung in der Struktur und dem Wachsthum der Thiere und Pflanzen. Schwann explained that the cell theory revealed the general principle of life. All living organisms are composed entirely of cells, and the formation of organs can be explained by the growth and reproduction of cells. Rudolf Virchow proclaimed in this context that "Life is essentially cellular activity". The cell theory thus opened up the prospect of a scientific theory of life, on which materialists were able to build a few years later.
Turning away from idealistic philosophy
Parallel to the methodological reorientation of the biological disciplines, a general criticism of the conservative legacy of German idealism developed in the intellectual climate of the Vormärz. In the natural sciences, criticism of natural philosophical methodology remained moderate, with many biologists remaining staunch anti-materialists. On the other hand, it was only a few years after Hegel died in 1831, when philosophical movements emerged that radically broke with German idealism in terms of ideology.
The critique of religion, as presented by Ludwig Feuerbach in The Essence of Christianity, was socially explosive and of particular importance. Feuerbach had attended every one of Hegel's lectures for over two years and wrote traditional idealist texts until the 1830s, having studied under Hegel in Berlin from 1824. However, Feuerbach and many other young students of Hegel began to have doubts. The young Hegelians were critical not only of the political conservatism of German idealism but also of the detached-from-empirical-observations philosophy of systems. In 1839, Feuerbach finally criticized his teacher's idealistic system in its principles. Although coherent and conclusive, it had distanced itself from sensory nature in an inadmissible way. Philosophy should be grounded in the sensual to arrive at a realization of nature and reality. "Vanity is therefore all speculation that seeks to go beyond nature and man." Feuerbach and the new biological movements shared the idea of a view of nature emancipated from speculation. However, Feuerbach's goal was an anthropological theory of man, not one of the natural sciences.
Feuerbach's explosive anthropology revealed itself most in his philosophy of religion. Idealist philosophy had erred in attempting to prove the truth of the theological doctrines through abstract arguments. In reality, he argued, religion was not a metaphysical truth, but an expression of human needs. The existence of God could not be proven by theologians and philosophers, as God was a human invention. Feuerbach's argument was not directed against religions in general. He acknowledged that there were certainly good reasons for religious belief. But he believed that these reasons were of a psychological nature, as religions satisfied real human needs. In contrast, philosophical-theological proofs of the existence of God were seen as speculative fantasies. Feuerbach's critique of religion was received as a radical attack on the cultural establishment, and by the mid-1840s, he had become the centre of philosophical renewal movements.
Carl Vogt and the political opposition
The materialism controversy was sparked by the materialist theses published by physiologist Carl Vogt from 1847 onwards. Vogt's turn towards materialism was influenced by the scientific and cultural renewal movements, as well as his political development. Vogt was born in Giessen in 1817 and grew up in a family that combined scientific and social revolutionary tendencies. Philipp Friedrich Wilhelm Vogt, Carl's father, was a medical professor in Giessen until he accepted a professorship in Bern in 1834 due to the threat of political persecution. The political entanglements were in the tradition of the family on his mother's side. Louise Follen's three brothers were all forced into emigration due to their nationalist and democratic activities.
In 1817 Adolf Follen drafted an outline for a future imperial constitution. Two years later, he was arrested for "German activities". His subsequent exile in Switzerland spared him from a 10-year prison sentence. Karl Follen defended tyrannicide in a pamphlet and was therefore considered the intellectual author of the assassination attempt on the writer August von Kotzebue. He managed to escape to the United States, where he established himself as a professor of German at Harvard University from 1825. In 1833 Paul Follen, the youngest of the Follen brothers, co-founded the Gießener Auswanderungsgesellschaft with Friedrich Münch. Although the society's goal of establishing a German republic in the United States was unsuccessful, Paul Follen eventually settled in Missouri and became a farmer.
Carl Vogt started studying medicine at Giessen in 1833, but switched to chemistry under the guidance of Justus Liebig. Liebig's experimental methods were in direct contrast to the idealistic philosophy of nature. As a co-founder of organic chemistry, Liebig rejected the separation between living processes and dead matter, providing Vogt with an intellectual foundation for the materialism that he later developed. However, in 1835, Vogt was unable to continue his studies in Giessen due to political circumstances. He had assisted a politically persecuted student to escape, which made him a target of the police. As a result, Vogt emigrated to Switzerland and completed his studies at the Faculty of Medicine in 1839.
During the early 1840s Vogt became involved with the political opposition and new scientific movements. However, he had not yet developed his ideological materialism at this point. It was during his three-year stay in Paris that Vogt's political and ideological radicalisation occurred. His acquaintance with anarchists Mikhail Bakunin and Pierre-Joseph Proudhon had a lasting influence on Vogt's political thinking. Starting in 1845, he began publishing his Physiologische Briefe, which presented physiology clearly and understandably based on Liebig's Chemische Briefe. The initial letters did not reference Vogt's materialism. Only in the letter on nerve power and mental activity, published in 1846, did Vogt state "that the seat of consciousness, will and thought must ultimately be sought solely in the brain".
Initially, political practice took precedence over materialist theory. Vogt had just been appointed professor of zoology in Giessen, through the influence of Liebig and Alexander von Humboldt, when the German Revolution began in March 1848 and democratic forces rose up against the so-called reaction in various parts of Germany. When the March Revolution reached the small university town of Giessen, Vogt was appointed commander of the militia and eventually represented the 6th electoral district of Hesse-Darmstadt in the Frankfurt Parliament from 1848 to 1849. After the Prussian King Frederick William IV rejected the imperial dignity offered to him and political defeats led to the dissolution of the National Assembly, Vogt moved to Stuttgart with the remaining 158 deputies to form the so-called rump parliament, which was forcibly dissolved after only a few weeks in early June 1849.
Appointed as one of the "five imperial regents" by the remaining parliament, Vogt found himself at the centre of the political opposition. On 18 June of that year, Württemberg troops occupied the conference venue. Vogt emigrated to Switzerland and took refuge in his parents' house. Having failed in his political ambitions and deprived of his academic career, he once again focused on biological studies, which he now interpreted in a radically ideological way.
Progression of the debate
Materialism controversy until 1854
In 1850, Vogt travelled to Nice to pursue zoological studies due to a lack of clear academic prospects. The following year, he published a book on animal states that combined zoology with a critical evaluation of the German state of affairs. The book contained a political plea in favour of anarchism, arguing that "every form of government, every law [is] a sign of the lack of completion of our state of nature". Vogt's biologistic argument in favour of anarchism was based on the idea that humans are natural and completely material organisms, in continuity with animal states. According to Vogt, biology implied both materialism and the subversion of the prevailing order. In his book, he referred unequivocally to the German situation:
Vogt succeeded in generating interest among the German public with his popular and polemical attacks. In 1852, he published Bilder aus dem Thierleben, which not only provided a detailed description of materialism but also strongly criticised German university scholars. It is argued that every biologist who thinks clearly must acknowledge the truth of materialism, as the dependence of soul functions on brain functions is evident. This dependence is most clearly shown in animal experiments, so "we can cut off the mental functions of the pigeon piece by piece by removing the brain piece by piece". But if the soul's functions depended on the brain in this way, the soul could not survive the death of the body. And if the brain functions are determined by the laws of nature, then the same must also apply to the soul.
According to Vogt, those who disagreed with these statements had not understood the necessary consequences of physiological research. This criticism was directed towards Rudolf Wagner, an anatomist and physiologist from Göttingen, who in 1851, had criticised Vogt in the Augsburger Allgemeine Zeitung for replacing God with a "blind, unconscious necessity". Wagner had also suggested that the soul of a child is composed of equal parts of the mother's and father's souls. Vogt found this idea to be a useful model. The concept of a composite child's soul not only contradicts the theological belief in the indivisibility of the soul, but is also physiologically nonsensical. Physical characteristics, such as facial features, are naturally inherited from parents to their children, and the same applies to the brain. This is why the inheritance of character traits can be easily explained in materialistic terms.
Göttingen Naturalists' Meeting
During the summer of 1854, the 31st Naturalists' Meeting was held in Göttingen. The meeting was dominated by the debate over the existence of a God-created soul. Wagner used this platform to deliver a lecture on human creation and the substance of the soul. In his lecture, he accused the materialists of undermining the moral foundations of social order by denying free will.
Vogt's materialism contradicted the moral responsibility of the researcher, as it reduced people to blind and irresponsible machines. In the same year, Wagner published a second paper in which he added to his moral criticisms with a general argument on the relationship between knowledge and faith. According to Wagner, these are two largely independent areas, meaning that no scientific knowledge can prove or disprove religious faith.
Physiologists describe the internal structure and function of physical organs. Materialists interpret these descriptions by identifying physical and mental functions. Dualists assume that bodily functions act on an immaterial soul. The natural sciences cannot decide the question of the soul, because neither interpretation could be derived from a physiological description. "There is not a single point in the biblical]doctrine of the soul ... that would contradict any doctrine of modern physiology and natural science."
Charcoal burning faith and science
Wagner's pamphlets brought the materialism debate to the centre of public interest. In response, Vogt wrote the polemic Köhlerglaube und Wissenschaft against Hofrath Rudolf Wagner in Göttingen. The first half of the text consists of ad hominem attacks against Wagner. It was alleged that he was not a serious and productive scientist, but merely adorned himself as the editor of countless works with the research work of others, and that he had also tried to suppress his materialistic critics with the help of state power. Wagner asserted that the materialist denial of free will was socially irresponsible in view of the political events of 1848 (March Revolution), in response to Vogt's anger.
In the second part of the work, Vogt systematically argued against Wagner's thesis of the compatibility of "naive Köhler faith" and scientific knowledge. Vogt stated that anyone who places the soul in a realm beyond empirical verifiability cannot be directly refuted by physiology. However, this assumption is ultimately useless and even incomprehensible. The relationship between soul and brain functions supports the idea of an identity between the body and soul, rather than confirming the axiom of the immaterial soul. This view is shared by Wagner, who acknowledges that all organs, except for the brain, are subject to biological processes. Wagner also does not propose the existence of a "muscle soul" that initiates muscle contraction. He does not argue that there is a kidney soul responsible for the excretion of metabolic products, in addition to the biological processes in the kidneys. "It is only in the case of the brain that this is not recognised; it is only in the case of the brain that a special, illogical conclusion that is not valid for the other organs is accepted".
Food, strength and substance
By 1855 the commitment to materialism had become an influential movement, despite Vogt's polemical theses facing resistance in academic and political circles. Vogt was supported by two younger scientists, Jakob Moleschott and Ludwig Büchner, who also published their materialist ideas in popular science publications. These three authors were portrayed as champions of materialism, which appeared to be conclusive. The debate surrounding materialism catalyzed intensifying popularisation efforts and ideological debates, not themselves without controversy, about the relationship between natural science and society. This led to discussions about the Darwinian theory of evolution from the late 1850s onwards.
Jakob Moleschott was born in 's-Hertogenbosch, the Netherlands, in 1822. He came into contact with Hegel's philosophy at an early age but eventually studied medicine in Heidelberg. Becoming strongly influenced by Feuerbach's philosophy, he focused on questions of metabolism and dietetics. Moleschott believed that food was the fundamental building block of both physical and mental functions, in line with his materialistic convictions. In his book 'Die Lehre der Nahrungsmittel: Für das Volk', Moleschott aimed to popularise his studies and presented detailed dietary plans for the impoverished sections of the population. The materialistic approach should not only deny the existence of an immaterial soul and God but also positively lead people to a better life.
In 1850 Moleschott sent a copy of his work to Feuerbach, who published an influential review titled Die Naturwissenschaft und die Revolution in the same year. In the 1840s, Feuerbach had defined his philosophy beyond idealism and materialism; now he explicitly supported the materialists. The philosophers continued to argue fruitlessly about the relationship between body and soul, while the natural sciences had already found the answer.
Büchner's relationship with the public was even more influential than Moleschott's alliance with Feuerbach. Born in Darmstadt in 1824, Büchner had already met Vogt as a student. In 1848, he became a member of the citizens' militia led by Vogt. After a few unhappy years as an assistant at the medical faculty in Tübingen, Büchner decided to publish a concise summary of the materialist worldview. Kraft und Stoff was a bestseller, with 12 editions published in the first 17 years, and translated into 16 languages. Unlike Vogt and Moleschott, Büchner presented materialism in a summary of findings that could be understood without prior philosophical or scientific knowledge, rather than in the context of his research. The starting point was the unity of force and substance, which Moleschott had already emphasised. Inherent forces are necessary for the existence of substance, just as substance is necessary as a carrier for forces. This unity directly implies the impossibility of immaterial souls, as they would have to exist without a material carrier.
Reactions in the 19th century
Philosophy of neo-Kantianism
Materialism was supported by natural scientists such as Vogt, Moleschott, and Büchner, who presented their theories as the consequences of empirical research. Following the collapse of German idealism, university philosophy appeared discredited as baseless speculation. Even the philosopher Feuerbach entrusted the natural sciences with resolving the philosophical question of the relationship between soul and body.
An influential philosophical critique of materialism did not develop until the 1860s with the emergence of Neo-Kantianism. In 1865, Otto Liebmann strongly criticised philosophical approaches from German idealism to Schopenhauer in his work Kant und die Epigonen, concluding each chapter with the statement "So we must go back to Kant!". Friedrich Albert Lange published his Geschichte des Materialismus the following year, in agreement with this position. Lange accused the materialists of "philosophical dilettantism", which, according to Kantian philosophy, ignored essential insights.
The Critique of Pure Reason's central theme was the question of the conditions of all possible knowledge, including scientific knowledge. Kant argued that human cognition does not depict the world as it really is. All knowledge is already characterized by categories such as "cause and effect" or "unity and multiplicity". These categories are not properties of the things themselves but are brought to the things by humans. Similarly, space and time lack absolute reality and are instead forms of human perception. As all knowledge is already characterised by categories and forms of perception, it is impossible for humans to recognise things in themselves. Therefore, it is not possible to scientifically prove or refute the existence of an immaterial soul, a personal God, or free will.
Lange argues that materialists made a fundamental error by disregarding Kant. Materialism posited that only matter exists, but failed to acknowledge that even scientific descriptions of matter do not describe absolute reality. Such descriptions already assume the categories and forms of perception, and therefore cannot be considered descriptions of things in themselves. Lange's argument is supported by the natural scientist Hermann von Helmholtz, who presented his work on sensory physiology in the 1850s as an empirical confirmation of Kant's work. In his 1855 lecture Ueber das Sehen des Menschen (On Human Vision), Helmholtz first described the physiological foundations of visual perception and then explained that vision is not a true-to-life representation of the outside world. Following Kant's philosophy, it is argued that human interpretation characterises every perception of the outside world, making it impossible to access things in themselves.
Ignoramus et ignorabimus
The scientific materialists did not engage with the arguments of the Neo-Kantians, as they saw the reference to Kant as just another speculative attack on the results of the natural sciences. However, the criticism of physiologist Emil Heinrich Du Bois-Reymond in his 1872 lecture Ueber die Grenzen des Naturerkennens, which declared consciousness to be a fundamental limit of the natural sciences, appeared more concerning. His phrase "Ignoramus et ignorabimus" (Latin for "We do not know and we will never know") sparked a long-lasting controversy regarding the concept of a scientific worldview. This controversy, known as the Ignorabimus controversy, was debated with similar fervour to the Vogt and Wagner debate 20 years prior, and even more so in the political arena. However, this time the materialists were on the defensive.
Du Bois-Reymond argued that the materialists' main problem was their inadequate argument in favour of the unity of brain and soul. Vogt, Moleschott, and Büchner only emphasized the dependence of soul functions on brain functions. Tests on animals had already demonstrated that damage to the brain leads to an impairment of mental functions. The concept of an immaterial soul is therefore rendered implausible by this dependency, making materialism the only acceptable conclusion. However, this consequence simply ignores the question of how the brain generates consciousness in the first place, how Büchner put it himself:
Du Bois-Reymond argued that proving dependency relationships was not enough to support materialism. To reduce consciousness to the brain, one must also explain it through brain functions. But the materialists were unable to provide such an explanation: "What conceivable connection is there between certain movements of certain atoms in my brain on the one hand, and on the other hand the original, undefinable, undeniable facts 'I feel pain, feel desire; I taste sweetness, smell the scent of roses, hear the sound of an organ, see red'." Du Bois-Reymond argued that there is no conceivable connection between the objectively described facts of the physical world and the subjectively determined facts of conscious experience. Therefore, consciousness represented a fundamental barrier to perceiving nature.
Du Bois-Reymond's Ignorabimus speech highlighted a fundamental weakness of scientific materialism. Although Vogt, Moleschott, and Büchner claimed that consciousness was material, they also acknowledged that brain functions could not explain it. This problem contributed to the development of a scientific worldview that shifted from materialism to monism in the late 19th century. Ernst Haeckel, the most famous proponent of a "monistic worldview", shared the materialists' rejection of dualism, idealism, and the concept of an immortal soul.
However, Haeckel's monism differs from materialism in that it does not recognise the primacy of matter. According to it, body and spirit are inseparable and equally fundamental aspects of a substance. This monism appears to circumvent du Bois-Reymond's problem. If matter and spirit are equally fundamental aspects of a substance, then spirit no longer needs to be explained by matter.
Büchner also viewed monism as the appropriate response to philosophical criticism of materialism. In a letter to Haeckel dated 1875, he wrote:
Political and ideological impact
Although the materialists gained popularity among the general public, they were not successful politically. Vogt, Moleschott, and Büchner lost their careers at German universities due to their advocacy of materialism. The revolutionary nature of Vogt's materialism could not succeed during the reactionary era after 1848. During the political movements of the latter half of the 19th century, scientific materialism failed to exert significant influence, partly due to differences with Karl Marx and Friedrich Engels. Marx labelled Vogt as a "small-university beer bouncer and misguided Barrot of the Reich", and the conflicts escalated into personal denunciations. For instance, Marx's circle also accused Vogt of having worked as a French spy.
The altered political situation is also apparent in the work of Ernst Haeckel, who embraced the concept of a scientific worldview from the materialists but gave it a fresh political orientation. Haeckel, who was 17 years younger than Vogt, established himself as a proponent of Darwinism in Germany during the 1860s. In his polemical rejection of "church-wisdom and ... after-philosophy", Haeckel closely resembled the scientific materialists. Vogt viewed physiology as the starting point for a scientific worldview, while Haeckel made a similar claim in referring to Charles Darwin:
However, for Haeckel, the concept of "progress" was primarily anti-clerical, opposing the church rather than the state. Bismarck's Kulturkampf, which began in 1871, provided Haeckel with an opportunity to connect anti-clerical monism with Prussian politics. As the First World War approached, Haeckel's statements became increasingly nationalistic, with racial theories and eugenics providing a seemingly scientific basis for chauvinistic politics. Therefore, Vogt's vision of a politically revolutionary natural science ultimately proved itself short-lived.
Reception in the 20th century
In the 19th century, scientific materialism played a significant role in ideological debates. The discussions around Darwin's theory of evolution and Haeckel's monism gained prominence in the 1860s. Nonetheless, the question of a scientific worldview remained controversial, and Büchner's Kraft und Stoff remained a bestseller.
The First World War and Haeckel's death in 1919 were significant turning points. In the Weimar Republic, the debates of the 1850s were no longer relevant, and the philosophical currents of the interwar period consistently criticised materialism, despite differences in content. This also applied to logical positivism, which adhered to the idea of a scientific worldview but interpreted it in an anti-metaphysical way. The logical positivists' criterion of meaning said that a proposition was only comprehensible if it could be verified empirically. This meant that materialism, monism, idealism, and dualism failed to meet this criterion and were considered misguided fantasies of a speculative era of philosophy. Materialist theories of consciousness were not revisited until the 1950s, when they were taken up from Anglo-Saxon philosophy. By this point, the scientific materialists of the 19th century had been forgotten. None of these new texts refer to Vogt, Moleschott or Büchner. Instead, the materialists of the post-war period focused on contemporary neuroscience.
Scientific materialism was largely ignored in the history of science and philosophy until the 1970s. Its reception in the GDR began relatively early under the influence of Dieter Wittich, who received his doctorate in 1960 with a thesis on the scientific materialists. In 1971, he published a collection of texts entitled Vogt, Moleschott, Büchner: Schriften zum kleinbürgerlichen Materialismus in Deutschland with Akademie Verlag. In his detailed introduction, Wittich, who held the only chair for epistemology in the GDR, honoured the political, scientific, and religious-critical work of the materialists. However, he also pointed out their philosophical shortcomings. He stated that the "petty-bourgeois materialists" were "vulgar materialists because they insisted on metaphysical materialism at a time when dialectical materialism had become not only a possibility but also a reality".
In 1977, Frederick Gregory, an American historian of science, published his monograph Scientific Materialism in Nineteenth Century Germany, which is still considered a standard work today. Gregory argues that the significance of Vogt, Moleschott and Büchner lies not in their specific elaboration of materialism, but rather in the social impact of their scientifically motivated criticism of religion, philosophy and politics. "The overwhelming trademark of the scientific materialists, as far as the historian is concerned, is not their materialism, but their atheism, more properly their humanistic religion."
In line with Gregory's judgement, the significance of the materialists in the secularisation process of the 19th century is generally acknowledged in the current research literature, while their philosophical positions are still subject to fierce criticism in some cases. Renate Wahsner, for example, explains: "It is not possible to contradict the view held in the literature, which denies all three of them sharpness and depth of thought". Not all authors share this negative assessment, with Kurt Bayertz, for example, defending the relevance of the scientific materialists, as they had developed "the first fully developed form of modern materialism ... Although the form of materialism developed by Vogt, Moleschott and Büchner is only one form of materialism, it is the form that is typical of modernity and the most influential and effective form today." An examination of current materialism controversies must therefore begin in the 19th century.
References
Bibliography
Primary literature
Secondary literature
External links
Digitised works of the scientific materialists in the Internet Archive
Zeno. "Lexikoneintrag zu »Materialismus«. Eisler, Rudolf: Wörterbuch der philosophischen ..." www.zeno.org (in German). Retrieved 2024-04-11.
Article on the materialism controversy in the German Medical Journal, 2006 (in German)
Scientific controversies
19th century in philosophy
Philosophy of biology
History of science
Materialism | Materialism controversy | [
"Physics",
"Technology"
] | 6,399 | [
"History of science",
"Materialism",
"History of science and technology",
"Matter"
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76,591,590 | https://en.wikipedia.org/wiki/PMCC%20polymer | Poly (tetrahydropyran-2-yl N-(2 methacryloxyethyl) carbamate)-b-(methyl 4-(3-methacryloyloxypropoxy) cinnamate) (PMCC) is a synthetic polymer with thermally active groups, which upon heating, decomposes and exposes primary amines, providing a basis for surface modification. The structure of PMCC is based on a PMMA backbone with different functional groups on its sidechain. It is soluble in cyclohexanone or chloroform and has been used to create bone tissue replicas and to study protein immobilization in biological sciences.
Structure and synthesis
PMCC is a cinnamate-carbamate copolymer synthesized by a mixture of methacrylate monomers, a cinnamate monomer ("A", methyl 4-(3-methacryloyloxypropoxy) cinnamate) and a carbamate monomer ("B", tetrahydropyran-2-yl N-(2-methacryloxyethyl) carbamate). Polymerization of the two synthesized monomers is carried out through a radical polymerization using azobisisobutrylnitrile (ABIN) in tetrahydropyran (THP) with the temperature of 60 °C.
Chemical properties
Pyrolysis
PMCC possesses two distinct decomposition/deprotection temperatures (Td). One starts around 150 °C and accounts for 80% of the mass loss, and the second starts around 210 °C that accounts for the last 20%. When decomposition temperature is 150-180 °C, the carbamate monomer "B" of PMCC tends to decompose to carbon dioxide, 3,4-Dihydro-2H-pyran and polymer with primary amine groups.
Applications
PMCC is used mainly as a functional layer for grafting chemicals on substrates in nanoscale chemical patterning together with thermochemical nanolithography (tc-SPL) which involves the use of a heated nanoscale tip to thermally deprotect amine groups on the PMCC polymer surface. Patterning resolution with tc-SPL on PMCC as small as sub-10 nm, with depths as small as sub-2nm and at speeds up to millimeters per second have been reported. After the deprotection of the PMCC, the chemical function of the pattern is achieved by attaching various nano-objects to exposed amine groups.
Liu et al. demonstrated the ability to create complex patterns with different functionalities by using PMCC and tc-SPL technology, including the electrostatic immobilization of negatively charged sulfonated enzymes at positively charged amine patterns. These capabilities have significant implications for nanobiotechnology, as they could be used for the development of protein chips, and in studies of nanoelectronics fabrications.
References
Polymers
Cinnamate esters
Tetrahydropyrans
Carbamates | PMCC polymer | [
"Chemistry",
"Materials_science"
] | 651 | [
"Polymers",
"Polymer chemistry"
] |
76,591,897 | https://en.wikipedia.org/wiki/The%20Jacobaeus%20Prize | The Jacobaeus Prize, (also known as the "Jacobæus Prize") is regarded as a prestigious recognition within the field of medical research. It is an annual award given to individuals who have made significant contributions to the advancement of medical science, particularly in the areas of physiology or endocrinology.
Background
Named after Hans Christian Jacobæus, a pioneering Swedish physician and researcher known for his contributions to the development of laparoscopy and thoracoscopy, the prize aims to honor those who continue to push the boundaries of medical research.
The prize was established to commemorate the legacy of Hans Christian Jacobæus, whose innovative work in the early 20th century laid the groundwork for minimally invasive surgery techniques. The award is sponsored by the Novo Nordisk Foundation.
Recipients
List of recipients of The Jacobæus Prize over the years:
References
Medicine awards
Awards established in 1985
Danish science and technology awards | The Jacobaeus Prize | [
"Technology"
] | 185 | [
"Science and technology awards",
"Medicine awards"
] |
76,592,348 | https://en.wikipedia.org/wiki/StackBlitz | StackBlitz is a collaborative online integrated development environment (IDE). The platform allows server-side software such as Node.js to be run entirely in the web browser, enabling fully online full-stack development. A number of web frameworks such as React, Next.js and Angular are supported.
History
StackBlitz was released to the public on August 2, 2017 by entrepreneur Eric Simons as an online integrated development environment for creating and sharing Angular and React projects. Prior to launching StackBlitz, Simons had attracted media attention by secretly living at AOL headquarters for two months in 2011 while working on a different startup company.
In May 2021, StackBlitz released WebContainers, a containerization solution that allowed server-side runtime environments such as Node.js to operate fully with web browsers. The company stated that the technology could boot development environments in less than a second, and was more secure than local environments due to running fully within the browser sandbox.
Features
StackBlitz offers an online integrated development environment that operates fully within a user's web browser as opposed to a more traditional local development environment. The software primarily emphasizes JavaScript development and has a large number of web framework templates readily available. Other Node.js, Python and PHP projects are also supported.
References
External links
2018 establishments in California
Online integrated development environments
2018 software
Web services | StackBlitz | [
"Technology"
] | 284 | [
"Computing stubs",
"World Wide Web stubs"
] |
76,592,604 | https://en.wikipedia.org/wiki/Remix%20%28web%20framework%29 | Remix is an open source full stack web framework. The software is designed for web applications built with front-end JavaScript frameworks like React and Vue.js. Remix supports server-side rendering and client-side routing. Remix has been presented as an alternative to the popular React framework Next.js. Initially available through a paid subscription, the software was made open source in October 2021. The team developing Remix (that also developed React Router) was acquired by Shopify in 2022, but has promised that development will stay open-source and "independent". The Remix team announced at React Conf 2024 that the next major version of Remix will be merged into and released as React Router v7.
References
External links
JavaScript web frameworks
Software using the MIT license
2021 software | Remix (web framework) | [
"Technology"
] | 164 | [
"Computing stubs",
"Software stubs"
] |
76,595,154 | https://en.wikipedia.org/wiki/Absolute%20Standards | Absolute Standards Inc. is a chemical company that makes chemical samples for use in calibrating laboratory testing equipment. The company is suspected to be a supplier of execution drugs for the Federal government of the United States.
Absolute Standards is not registered with the Food and Drug Administration (FDA), nor is it registered as a controlled substances manufacturer with the Drug Enforcement Administration (DEA). Therefore, despite allegedly producing ingredients for lethal injections, Absolute Standards is not authorized to produce drugs for human consumption.
Products
Calibration Chemicals
Absolute Standards advertises itself as producing over 2,000 calibration chemical products designed to assist with the testing and analysis of instruments used in laboratories, and claims to ship their products to all fifty U.S. states, several territories, and over thirty countries.
Pentobarbital
Absolute Standards applied to be registered as a bulk manufacturer of pentobarbital on September 29, 2018, and again on August 25, 2021, according to Drug Enforcement Administration notices. The first notice stated that the company planned to bulk manufacture the substance for distribution to customers, while the 2021 notice mentioned that the company intended to bulk manufacture the controlled substances "for internal use and sale to its customers."
In May 2024, Absolute Standards president John P. Criscio sent a letter to Connecticut state senator Saud Anwar and state representative Josh Elliott informing them that had company had ceased the manufacture and sale of pentobarbital in December 2020, marking the first written acknowledgment by Criscio that the company had been manufacturing pentobarbital, and stating that the company had no intention of resuming its production.
Apart from its use in lethal injections, pentobarbital can also treat tension, anxiety, insomnia, epilepsy, and other seizures. Additionally, it can be used to help patients relax before surgery. Absolute Standards, however, provides chemical standards to chemical testing laboratories and isn't a provider of drugs for pharmaceutical or hospital use.
Investigations
In 2020, Reuters suspected that Absolute Standards, based on a letter signed by Democratic Party members of the US House Oversight Committee, was the manufacturer of a raw, powdered form of pentobarbital for the Justice Department. According to Reuters, the department has confirmed hiring a pharmacy to mix this powder into a sterile, injectable solution. When asked about the claims, Stephen Arpie (Director) told Reuters that they "don't know what the final intended use" of their products is going to be.
In April 2021, Jennifer Lamb, the district director for Congresswoman Rosa DeLauro, wrote to Connecticut Attorney General William Tong about Absolute Standards, saying, “It appears the company may have supplied the US Department of Justice with ingredients used to make pentobarbital for use in federal executions." In May 2021, Tong wrote to Absolute Standards requesting details about the company’s activities, expressing concern that the company might “also be providing pentobarbital, or contemplating providing the drug, for use by individual states in their attempts to execute human beings.”
On a 2024 episode of the television series Last Week Tonight, Absolute Standards was again accused of supplying pentobarbital to the federal government. This claim was based on information from a confidential source and a Freedom of Information request filed with the DEA in 2020. The processing of this request was significantly delayed, reportedly due to the documents being "related to the death penalty," according to an agency liaison.
In a separate investigation, The Intercept requested records detailing communications between the South Carolina Department of Corrections and Absolute Standards. This was following the announcement in September 2023 by South Carolina officials that the state had secured pentobarbital for carrying out executions by lethal injection. The Department of Corrections replied that the information requested was exempt from disclosure, due in part to a state secrecy law that shields the identity of people and companies involved in executions. The Intercept also cites two unnamed sources, both of whom report being told by Stephen Arpie and John Criscio that Absolute Standards made drugs for executions.
References
1990 establishments in Connecticut
American companies established in 1990
Chemical companies established in 1990
Chemical companies of the United States
Manufacturing companies based in Connecticut
Lethal injection
Hamden, Connecticut | Absolute Standards | [
"Environmental_science"
] | 860 | [
"Toxicology",
"Lethal injection"
] |
76,595,186 | https://en.wikipedia.org/wiki/NGC%204157 | NGC 4157 is a spiral galaxy in the constellation Ursa Major. The galaxy lies about 55 million light years away from Earth, which means, given its apparent dimensions, that NGC 4157 is approximately 125,000 light years across. It was discovered by William Herschel on March 9, 1788.
Characteristics
NGC 4157 seen nearly edge-on, with an inclination of 84° based on CO imaging. The total stellar mass of NGC 4157 is , while the dust mass is estimated to be . The hydrogen disk of NGC 4157 is symmetric and slightly wrapped, indicating no strong interaction with other galaxies, and extends to twice the size of the optical disk. The total HI mass in the galaxy is estimated to be .
The star formation rate of the galaxy is per year. A star formation area is visible beyond the end of the optical disk and is also visible in X-ray and ultraviolet imaging. It could probably be the result of a recent accretion.
The galaxy has radio emission extending above and below the optical disk, indicating the presence of a radio halo. There is also radio emission extending southwards from the north-eastern end of the disk.
Supernovae
Three supernovae have been observed in NGC 4157:
SN 1937A (type unknown, mag. 16.2) was discovered by Fritz Zwicky on 16 February 1937.
SN 1955A (type unknown, mag. 16) was discovered by Fritz Zwicky on 14 April 1955.
SN 2003J (type II, mag. 16.7) was discovered by R. Kushida, T. Puckett, and J. Newton on 11 January 2003.
Nearby galaxies
NGC 4157 is the foremost galaxy of the NGC 4157 Group. Other members of the group include NGC 4085, NGC 4088, UGC 6992, and UGC 7176. UGC 7176 is a companion of NGC 4157, lying 12 arcminutes away. The group is part of the Ursa Major Cluster, a large association of mostly spiral galaxies lying north of the Virgo Cluster, that is part of the Local Supercluster. NGC 4157 is one of the dominant galaxies in the cluster, along with NGC 3769, NGC 3877, NGC 3992, NGC 4111, NGC 4217 and NGC 4346.
References
External links
Spiral galaxies
Ursa Major
Ursa Major Cluster
4157
07183
+09-20-106
12085+5045
38795
Discoveries by William Herschel
Astronomical objects discovered in 1788 | NGC 4157 | [
"Astronomy"
] | 521 | [
"Ursa Major",
"Constellations"
] |
76,595,512 | https://en.wikipedia.org/wiki/NGC%204096 | NGC 4096 is a spiral galaxy in the constellation Ursa Major. The galaxy lies about 35 million light years away from Earth, which means, given its apparent dimensions, that NGC 4096 is approximately 80,000 light years across. It was discovered by William Herschel on March 9, 1788.
NGC 4096 is a spiral galaxy visible with an inclination of 76°. Although the presence of a bar has been suggested, it hasn't been proven. The galaxy has multiple well-defined thin arms. NGC 4096 is asymmetric in the north–south axis, with the northern half having stronger CO emissions and asymmetric HI and H-alpha emissions following a lopsided spiral arm. The total stellar mass of the galaxy is estimated to be . The star formation rate of the galaxy is estimated to be between 0.22 and 0.43 per year.
Two supernovae have been detected in NGC 4096. SN 1960H was a type Ia-pec supernova which had an apparent magnitude of 14.5 at discovery. SN 2014bi was a low-luminosity type II-P supernova with magnitude 18.2 upon discovery. The spectrum indicated it was about two weeks post maximum and significantly reddened.
Garcia in 1993 considered the galaxy to be a member of LGG 269 group, along with NGC 4111, NGC 3938, NGC 4051, and NGC 4138. On the other hand, Makarov et al. consider the galaxy to be a member of the Messier 106 Group, along with Messier 106, NGC 4242, NGC 4248, NGC 4288 and NGC 4460. The group is part of the Local Supercluster.
References
External links
Intermediate spiral galaxies
Ursa Major
Canes II Group
4096
07090
+08-22-067
12034+4745
38361
Discoveries by William Herschel
Astronomical objects discovered in 1788 | NGC 4096 | [
"Astronomy"
] | 399 | [
"Ursa Major",
"Constellations"
] |
76,598,831 | https://en.wikipedia.org/wiki/Pharmacology%20of%20ethanol | The pharmacology of ethanol involves both pharmacodynamics (how it affects the body) and pharmacokinetics (how the body processes it). In the body, ethanol primarily affects the central nervous system, acting as a depressant and causing sedation, relaxation, and decreased anxiety. The complete list of mechanisms remains an area of research, but ethanol has been shown to affect ligand-gated ion channels, particularly the GABAA receptor.
After oral ingestion, ethanol is absorbed via the stomach and intestines into the bloodstream. Ethanol is highly water-soluble and diffuses passively throughout the entire body, including the brain. Soon after ingestion, it begins to be metabolized, 90% or more by the liver. One standard drink is sufficient to almost completely saturate the liver's capacity to metabolize alcohol.[citation needed] The main metabolite is acetaldehyde, a toxic carcinogen. Acetaldehyde is then further metabolized into ionic acetate by the enzyme aldehyde dehydrogenase (ALDH). Acetate is not carcinogenic and has low toxicity, but has been implicated in causing hangovers. Acetate is further broken down into carbon dioxide and water and eventually eliminated from the body through urine and breath. 5 to 10% of ethanol is excreted unchanged in the breath, urine, and sweat.
History
Beginning with the Gin Craze, excessive drinking and drunkenness developed into a major problem for public health. In 1874, Francis E. Anstie's experiments showed that the amounts of alcohol eliminated unchanged in breath, urine, sweat, and feces were negligible compared to the amount ingested, suggesting it was oxidized within the body. In 1902, Atwater and Benedict estimated that alcohol yielded 7.1 kcal of energy per gram consumed and 98% was metabolized. In 1922, Widmark published his method for analyzing the alcohol content of fingertip samples of blood.
Through the 1930s, Widmark conducted numerous studies and formulated the basic principles of ethanol pharmacokinetics for forensic purposes, including the eponymous Widmark equation. In 1980, Watson et al. proposed updated equations based on total body water instead of body weight. The TBW equations have been found to be significantly more accurate due to rising levels of obesity worldwide.
Pharmacodynamics
The principal mechanism of action for ethanol has proven elusive and remains not fully understood. Identifying molecular targets for ethanol is unusually difficult, in large part due to its unique biochemical properties. Specifically, ethanol is a very low molecular weight compound and is of exceptionally low potency in its actions, causing effects only at very high (millimolar mM) concentrations. For these reasons, it is not possible to employ traditional biochemical techniques to directly assess the binding of ethanol to receptors or ion channels. Instead, researchers have had to rely on functional studies to elucidate the actions of ethanol. Even at present, no binding sites have been unambiguously identified and established for ethanol. Studies have published strong evidence for certain functions of ethanol in specific systems, but other laboratories have found that these findings do not replicate with different neuronal types and heterologously expressed receptors. Thus, there remains lingering doubt about the mechanisms of ethanol listed here, even for the GABAA receptor, the most-studied mechanism.
In the past, alcohol was believed to be a non-specific pharmacological agent affecting many neurotransmitter systems in the brain, but progress has been made over the last few decades. It appears that it affects ion channels, in particular ligand-gated ion channels, to mediate its effects in the CNS. In some systems, these effects are facilitatory, and in others inhibitory. Moreover, although it has been established that ethanol modulates ion channels to mediate its effects, ion channels are complex proteins, and their interactions and functions are complicated by diverse subunit compositions and regulation by conserved cellular signals (e.g. signaling lipids).
Alcohol is also converted into phosphatidylethanol (PEth, an unnatural lipid metabolite) by phospholipase D2. This metabolite competes with PIP2 agonist sites on lipid-gated ion channels. The result of these direct effects is a wave of further indirect effects involving a variety of other neurotransmitter and neuropeptide systems. This presents a novel indirect mechanism and suggests that a metabolite, not the ethanol itself, could cause the behavioural or symptomatic effects of alcohol intoxication. Many of the primary targets of ethanol are known to bind PIP2 including GABAA receptors, but the role of PEth needs to be investigated further.
List of known actions in the central nervous system
Ethanol has been reported to possess the following actions in functional assays at varying concentrations:
GABAA receptor: positive allosteric modulator (primarily of δ subunit-containing receptors)
NMDA receptor: negative allosteric modulator
AMPA receptor: negative allosteric modulator
Kainate receptor: negative allosteric modulator
Glycine receptor: positive allosteric modulator
Serotonin 5-HT3 receptor: positive allosteric modulator
Opioid receptor: endogenous positive allosteric modulator
Muscarinic acetylcholine receptor: positive allosteric modulator.
Nicotinic acetylcholine receptor: positive allosteric modulator
Glycine reuptake inhibitor
Adenosine reuptake inhibitor
L-type calcium channel: channel blocker
GIRK: channel opener
Voltage-gated calcium channel
Dihydropyridine-sensitive L-type Ca2+ channels
BK channel modulation
G-protein-activated inwardly rectifying K+ channels
Brain medulla: Decreased levels of nitric oxide
Mesolimbic pathway: Increased levels of dopamine and endogenous opioids, secondary to other actions
Many of these actions have been found to occur only at very high concentrations that may not be pharmacologically significant at recreational doses of ethanol, and it is unclear how or to what extent each of the individual actions is involved in the effects of ethanol. Some of the actions of ethanol on ligand-gated ion channels, specifically the nicotinic acetylcholine receptors and the glycine receptor, are dose-dependent, with potentiation or inhibition occurring dependent on ethanol concentration. This seems to be because the effects of ethanol on these channels are a summation of positive and negative allosteric modulatory actions.
GABAA receptors
Ethanol has been found to enhance GABAA receptor-mediated currents in functional assays. Ethanol has long shown a similarity in its effects to positive allosteric modulators of the GABAA receptor like benzodiazepines, barbiturates, and various general anesthetics. Some of these effects include anxiolytic, anticonvulsant, sedative, and hypnotic effects, cognitive impairment, and motor incoordination. In accordance, it was theorized and widely believed that the primary mechanism of action of ethanol is GABAA receptor positive allosteric modulation. However, other ion channels are involved in its effects as well. Although ethanol exhibits positive allosteric binding properties to GABAA receptors, its effects are limited to pentamers containing the δ-subunit rather than the γ-subunit. Ethanol potentiates extrasynaptic δ subunit-containing GABAA receptors at behaviorally relevant (as low as 3 mM) concentrations, but γ subunit receptors are enhanced only at far higher concentrations (> 100 mM) that are in excess of recreational concentrations (up to 50 mM).
GABAA receptors containing the δ-subunit have been shown to be located exterior to the synapse and are involved with tonic inhibition rather than its γ-subunit counterpart, which is involved in phasic inhibition. The δ-subunit has been shown to be able to form the allosteric binding site which makes GABAA receptors containing the δ-subunit more sensitive to ethanol concentrations, even to moderate social ethanol consumption levels (30mM). While it has been shown by Santhakumar et al. that GABAA receptors containing the δ-subunit are sensitive to ethanol modulation, depending on subunit combinations receptors could be more or less sensitive to ethanol. It has been shown that GABAA receptors that contain both δ and β3-subunits display increased sensitivity to ethanol. One such receptor that exhibits ethanol insensitivity is α3-β6-δ GABAA. It has also been shown that subunit combination is not the only thing that contributes to ethanol sensitivity. Location of GABAA receptors within the synapse may also contribute to ethanol sensitivity.
Ro15-4513, a close analogue of the benzodiazepine antagonist flumazenil (Ro15-1788), has been found to bind to the same site as ethanol and to competitively displace it in a saturable manner. In addition, Ro15-4513 blocked the enhancement of δ subunit-containing GABAA receptor currents by ethanol in vitro. In accordance, the drug has been found to reverse many of the behavioral effects of low-to-moderate doses of ethanol in rodents, including its effects on anxiety, memory, motor behavior, and self-administration. Taken together, these findings suggest a binding site for ethanol on subpopulations of the GABAA receptor with specific subunit compositions via which it interacts with and potentiates the receptor.
Calcium channel blocking
Research indicates ethanol is involved in the inhibition of L-type calcium channels. One study showed the nature of ethanol binding to L-type calcium channels is according to first-order kinetics with a Hill coefficient around 1. This indicates ethanol binds independently to the channel, expressing noncooperative binding. Early studies showed a link between calcium and the release of vasopressin by the secondary messenger system. Vasopressin levels are reduced after the ingestion of alcohol. The lower levels of vasopressin from the consumption of alcohol have been linked to ethanol acting as an antagonist to voltage-gated calcium channels (VGCCs). Studies conducted by Treistman et al. in the aplysia confirm inhibition of VGCC by ethanol. Voltage clamp recordings have been done on the aplysia neuron. VGCCs were isolated and calcium current was recorded using patch clamp technique having ethanol as a treatment. Recordings were replicated at varying concentrations (0, 10, 25, 50, and 100 mM) at a voltage clamp of +30 mV. Results showed calcium current decreased as concentration of ethanol increased. Similar results have shown to be true in single-channel recordings from isolated nerve terminal of rats that ethanol does in fact block VGCCs.
Studies done by Katsura et al. in 2006 on mouse cerebral cortical neurons, show the effects of prolonged ethanol exposure. Neurons were exposed to sustained ethanol concentrations of 50 mM for 3 days in vitro. Western blot and protein analysis were conducted to determine the relative amounts of VGCC subunit expression. α1C, α1D, and α2/δ1 subunits showed an increase of expression after sustained ethanol exposure. However, the β4 subunit showed a decrease. Furthermore, α1A, α1B, and α1F subunits did not alter in their relative expression. Thus, sustained ethanol exposure may participate in the development of ethanol dependence in neurons.
Other experiments done by Malysz et al. have looked into ethanol effects on voltage-gated calcium channels on detrusor smooth muscle cells in guinea pigs. Perforated patch clamp technique was used having intracellular fluid inside the pipette and extracellular fluid in the bath with added 0.3% vol/vol (about 50-mM) ethanol. Ethanol decreased the current in DSM cells and induced muscle relaxation. Ethanol inhibits VGCCs and is involved in alcohol-induced relaxation of the urinary bladder.
Rewarding and reinforcing actions
The reinforcing effects of alcohol consumption are mediated by acetaldehyde generated by catalase and other oxidizing enzymes such as cytochrome P-4502E1 in the brain. Although acetaldehyde has been associated with some of the adverse and toxic effects of ethanol, it appears to play a central role in the activation of the mesolimbic dopamine system.
Ethanol's rewarding and reinforcing (i.e., addictive) properties are mediated through its effects on dopamine neurons in the mesolimbic reward pathway, which connects the ventral tegmental area to the nucleus accumbens (NAcc). One of ethanol's primary effects is the allosteric inhibition of NMDA receptors and facilitation of GABAA receptors (e.g., enhanced GABAA receptor-mediated chloride flux through allosteric regulation of the receptor). At high doses, ethanol inhibits most ligand-gated ion channels and voltage-gated ion channels in neurons as well.
With acute alcohol consumption, dopamine is released in the synapses of the mesolimbic pathway, in turn heightening activation of postsynaptic D1 receptors. The activation of these receptors triggers postsynaptic internal signaling events through protein kinase A, which ultimately phosphorylate cAMP response element binding protein (CREB), inducing CREB-mediated changes in gene expression.
With chronic alcohol intake, consumption of ethanol similarly induces CREB phosphorylation through the D1 receptor pathway, but it also alters NMDA receptor function through phosphorylation mechanisms; an adaptive downregulation of the D1 receptor pathway and CREB function occurs as well. Chronic consumption is also associated with an effect on CREB phosphorylation and function via postsynaptic NMDA receptor signaling cascades through a MAPK/ERK pathway and CAMK-mediated pathway. These modifications to CREB function in the mesolimbic pathway induce expression (i.e., increase gene expression) of ΔFosB in the , where ΔFosB is the "master control protein" that, when overexpressed in the NAcc, is necessary and sufficient for the development and maintenance of an addictive state (i.e., its overexpression in the nucleus accumbens produces and then directly modulates compulsive alcohol consumption).
Relationship between concentrations and effects
Recreational concentrations of ethanol are typically in the range of 1 to 50 mM. Very low concentrations of 1 to 2 mM ethanol produce zero or undetectable effects except in alcohol-naive individuals. Slightly higher levels of 5 to 10 mM, which are associated with light social drinking, produce measurable effects including changes in visual acuity, decreased anxiety, and modest behavioral disinhibition. Further higher levels of 15 to 20 mM result in a degree of sedation and motor incoordination that is contraindicated with the operation of motor vehicles. In jurisdictions in the U.S., maximum blood alcohol levels for legal driving are about 17 to 22 mM. In the upper range of recreational ethanol concentrations of 20 to 50 mM, depression of the central nervous system is more marked, with effects including complete drunkenness, profound sedation, amnesia, emesis, hypnosis, and eventually unconsciousness. Levels of ethanol above 50 mM are not typically experienced by normal individuals and hence are not usually physiologically relevant; however, such levels – ranging from 50 to 100 mM – may be experienced by alcoholics with high tolerance to ethanol. Concentrations above this range, specifically in the range of 100 to 200 mM, would cause death in all people except alcoholics.
As drinking increases, people become sleepy or fall into a stupor. After a very high level of consumption, the respiratory system becomes depressed and the person will stop breathing. Comatose patients may aspirate their vomit (resulting in vomitus in the lungs, which may cause "drowning" and later pneumonia if survived). CNS depression and impaired motor coordination along with poor judgment increase the likelihood of accidental injury occurring. It is estimated that about one-third of alcohol-related deaths are due to accidents and another 14% are from intentional injury.
In addition to respiratory failure and accidents caused by its effects on the central nervous system, alcohol causes significant metabolic derangements. Hypoglycaemia occurs due to ethanol's inhibition of gluconeogenesis, especially in children, and may cause lactic acidosis, ketoacidosis, and acute kidney injury. Metabolic acidosis is compounded by respiratory failure. Patients may also present with hypothermia.
Pharmacokinetics
The pharmacokinetics of ethanol are well characterized by the ADME acronym (absorption, distribution, metabolism, excretion). Besides the dose ingested, factors such as the person's total body water, speed of drinking, the drink's nutritional content, and the contents of the stomach all influence the profile of blood alcohol content (BAC) over time. Breath alcohol content (BrAC) and BAC have similar profile shapes, so most forensic pharmacokinetic calculations can be done with either. Relatively few studies directly compare BrAC and BAC within subjects and characterize the difference in pharmacokinetic parameters. Comparing arterial and venous BAC, arterial BAC is higher during the absorption phase and lower in the postabsorptive declining phase.
Endogenous production
All organisms produce alcohol in small amounts by several pathways, primarily through fatty acid synthesis, glycerolipid metabolism, and bile acid biosynthesis pathways.
Fermentation is a biochemical process during which yeast and certain bacteria convert sugars to ethanol, carbon dioxide, as well as other metabolic byproducts. The average human digestive system produces approximately 3g of ethanol per day through fermentation of its contents. Such production generally does not have any forensic significance because the ethanol is broken down before significant intoxication ensues. These trace amounts of alcohol range from 0.1 to in the blood of healthy humans, with some measurements as high as .
Auto-brewery syndrome is a condition characterized by significant fermentation of ingested carbohydrates within the body. In rare cases, intoxicating quantities of ethanol may be produced, especially after eating meals. Claims of endogenous fermentation have been attempted as a defense against drunk driving charges, some of which have been successful, but the condition is under-researched.
Absorption
Ethanol is most commonly ingested by mouth, but other routes of administration are possible, such as inhalation, enema, or by intravenous injection. With oral administration, the ethanol is absorbed into the portal venous blood through the mucosa of the gastrointestinal tract, such as in the oral cavity, stomach, duodenum, and jejunum. The oral bioavailability of ethanol is quite high, with estimates ranging from 80% at a minimum to 94%-96%. The ethanol molecule is small and uncharged, and easily crosses biological membranes by passive diffusion. The absorption rate of ethanol is typically modeled as a first-order kinetic process depending on the concentration gradient and specific membrane. The rate of absorption is fastest in the duodenum and jejunum, owing to the larger absorption surface area provided by the villi and microvilli of the small intestines. Gastric emptying is therefore an important consideration when estimating the overall rate of absorption in most scenarios; the presence of a meal in the stomach delays gastric emptying, and absorption of ethanol into the blood is consequently slower. Due to irregular gastric emptying patterns, the rate of absorption of ethanol is unpredictable, varying significantly even between drinking occasions. In experiments, aqueous ethanol solutions have been given intravenously or rectally to avoid this variation. The delay in ethanol absorption caused by food is similar regardless of whether food is consumed just before, at the same time, or just after ingestion of ethanol. The type of food, whether fat, carbohydrates, or protein, also is of little importance. Not only does food slow the absorption of ethanol, but it also reduces the bioavailability of ethanol, resulting in lower circulating concentrations.
Regarding inhalation, early experiments with animals showed that it was possible to produce significant BAC levels comparable to those obtained by injection, by forcing the animal to breathe alcohol vapor. In humans, concentrations of ethanol in air above 10 mg/L caused initial coughing and smarting of the eyes and nose, which went away after adaptation. 20 mg/L was just barely tolerable. Concentrations above 30 mg/L caused continuous coughing and tears, and concentrations above 40 mg/L were described as intolerable, suffocating, and impossible to bear for even short periods. Breathing air with concentration of 15 mg/L ethanol for 3 hours resulted in BACs from 0.2 to 4.5 g/L, depending on breathing rate. It is not a particularly efficient or enjoyable method of becoming intoxicated.
Ethanol is not absorbed significantly through intact skin. The steady state flux is . Applying a 70% ethanol solution to a skin area of for 1 hr would result in approximately of ethanol being absorbed. The substantially increased levels of ethanol in the blood reported for some experiments are likely due to inadvertent inhalation. A study that did not prevent respiratory uptake found that applying 200 mL of hand disinfectant containing 95% w/w ethanol (150 g ethanol total) over the course of 80 minutes in a 3-minutes-on 5-minutes-off pattern resulted in the median BAC among volunteers peaking 30 minutes after the last application at 17.5 mg/L (0.00175%). This BAC roughly corresponds to drinking one gram of pure ethanol. Ethanol is rapidly absorbed through cut or damaged skin, with reports of ethanol intoxication and fatal poisoning.
The timing of peak blood concentration varies depends on the type of alcoholic drink:
Vodka tonic: 36 ± 10 minutes after consumption
Wine: 54 ± 14 minutes
Beer: 62 ± 23 minutes
Also, carbonated alcoholic drinks seem to have a shorter onset compare to flat drinks in the same volume. One theory is that carbon dioxide in the bubbles somehow speeds the flow of alcohol into the intestines.
Absorption is reduced by a large meal. Stress speeds up absorption.
Distribution
After absorption, the alcohol goes through the portal vein to the liver, then through the hepatic veins to the heart, then the pulmonary arteries to the lungs, then the pulmonary veins to the heart again, and then enters systemic circulation. Once in systematic circulation, ethanol distributes throughout the body, diffusing passively and crossing all biological membranes including the blood-brain barrier. At equilibrium, ethanol is present in all body fluids and tissues in proportion to their water content. Ethanol does not bind to plasma proteins or other biomolecules. The rate of distribution depends on blood supply, specifically the cross-sectional area of the local capillary bed and the blood flow per gram of tissue. As such, ethanol rapidly affects the brain, liver, and kidneys, which have high blood flow. Other tissues with lower circulation, such as skeletal muscles and bone, require more time for ethanol to distribute into. In rats, it takes around 10–15 minutes for tissue and venous blood to reach equilibrium. Peak circulating levels of ethanol are usually reached within a range of 30 to 90 minutes of ingestion, with an average of 45 to 60 minutes. People who have fasted overnight have been found to reach peak ethanol concentrations more rapidly, at within 30 minutes of ingestion.
The volume of distribution contributes about 15% of the uncertainty to Widmark's equation and has been the subject of much research. Widmark originally used units of mass (g/kg) for EBAC, thus he calculated the apparent of distribution or mass of blood in kilograms. He fitted an equation of the body weight in kg, finding an average rho-factor of 0.68 for men and 0.55 for women. This has units of dose per body weight (g/kg) divided by concentration (g/kg) and is therefore dimensionless. However, modern calculations use weight/volume concentrations (g/L) for EBAC, so Widmark's rho-factors must be adjusted for the density of blood, 1.055 g/mL. This has units of dose per body weight (g/kg) divided by concentration (g/L blood) - calculation gives values of 0.64 L/kg for men and 0.52 L/kg for women, lower than the original. Newer studies have updated these values to population-average of 0.71 L/kg for men and 0.58 L/kg for women. But individual values may vary significantly - the 95% range for is 0.58-0.83 L/kg for males and 0.43-0.73 L/kg for females. A more accurate method for calculating is to use total body water (TBW) - experiments have confirmed that alcohol distributes almost exactly in proportion to TBW within the Widmark model. TBW may be calculated using body composition analysis or estimated using anthropometric formulas based on age, height, and weight. is then given by , where is the water content of blood, approximately 0.825 w/v for men and 0.838 w/v for women.
These calculations assume Widmark's zero-order model for the effects of metabolization, and assume that TBW is almost exactly the volume of distribution of ethanol. Using a more complex model that accounts for non-linear metabolism, Norberg found that Vd was only 84-87% of TBW. This finding was not reproduced in a newer study which found volumes of distribution similar to those in the literature.
Metabolism
Several metabolic pathways exist:
One pathway involves alcohol dehydrogenase, particularly the IB (class I), beta polypeptide (ADH1B, EC 1.1.1.1) enzyme. The reaction uses NAD+ to convert the ethanol into acetaldehyde (a toxic carcinogen). The enzyme acetaldehyde dehydrogenase (aldehyde dehydrogenase 2 family ALDH2, EC 1.2.1.3) then converts the acetaldehyde into the non-toxic acetate ion (commonly found in acetic acid or vinegar). This ion is in turn is broken down into carbon dioxide and water. Specifically, acetate combines with coenzyme A (acetyl-CoA synthetase) to form acetyl-CoA, via the enzymes acyl-CoA synthetase short-chain family member 2 ACSS2 (EC 6.2.1.1) and acetyl-CoA synthase 2 (ACSS1). acetyl-CoA then participates in the citric acid cycle. At even low physiological concentrations, ethanol completely saturates alcohol dehydrogenase. This is because ethanol has high affinity for the enzyme and very high concentrations of ethanol occur when it is used as a recreational substance.
The microsomal ethanol-oxidizing system (MEOS), specifically mediated by the cytochrome P450 enzyme CYP2E1, is another major route of ethanol metabolism. CYP2E1 is predominantly active at higher concentrations. Repeated or chronic use of ethanol increases the activity of CYP2E1.
The activity of ADH and CYP2E1 alone does not appear sufficient to fully explain the increase in ethanol metabolism rate. There may be one or more additional pathways that metabolize as much as 25 to 35% of ethanol at typical concentrations.
A small amount of ethanol undergoes conjugation to form ethyl glucuronide and ethyl sulfate.
Detailed ADH pathway
The reaction from ethanol to carbon dioxide and water proceeds in at least 11 steps in humans. C2H6O (ethanol) is converted to C2H4O (acetaldehyde), then to C2H4O2 (acetic acid), then to acetyl-CoA. Once acetyl-CoA is formed, it is free to enter directly into the citric acid cycle (TCA) and is converted to 2 CO2 molecules in 8 reactions. The equations:
C2H6O(ethanol) + NAD+ → C2H4O(acetaldehyde) + NADH + H+
C2H4O(acetaldehyde) + NAD+ + H2O → C2H4O2(acetic acid) + NADH + H+
C2H4O2(acetic acid) + CoA + ATP → Acetyl-CoA + AMP + PPi
The Gibbs free energy is simply calculated from the free energy of formation of the product and reactants. If catabolism of alcohol goes all the way to completion, then there is a very exothermic event yielding some of energy. If the reaction stops part way through the metabolic pathways, which happens because acetic acid is excreted in the urine after drinking, then not nearly as much energy can be derived from alcohol, indeed, only . At the very least, the theoretical limits on energy yield are determined to be to . The first with NADH is endothermic, requiring of alcohol, or about 3 molecules of adenosine triphosphate (ATP) per molecule of ethanol.
Variation
Variations in genes influence alcohol metabolism and drinking behavior. Certain amino acid sequences in the enzymes used to oxidize ethanol are conserved (unchanged) going back to the last common ancestor over 3.5bya. Evidence suggests that humans evolved the ability to metabolize dietary ethanol between 7 and 21 million years ago, in a common ancestor shared with chimpanzees and gorillas but not orangutans. Gene variation in these enzymes can lead to variation in catalytic efficiency between individuals. Some individuals have less effective metabolizing enzymes of ethanol, and can experience more marked symptoms from ethanol consumption than others. However, those having acquired alcohol tolerance have a greater quantity of these enzymes, and metabolize ethanol more rapidly. Specifically, ethanol has been observed to be cleared more quickly by regular drinkers than non-drinkers.
Falsely high BAC readings may be seen in patients with kidney or liver disease or failure. Such persons also have impaired acetaldehyde dehydrogenase, which causes acetaldehyde levels to peak higher, producing more severe hangovers and other effects such as flushing and tachycardia. Conversely, members of certain ethnicities that traditionally did not use alcoholic beverages have lower levels of alcohol dehydrogenases and thus "sober up" very slowly but reach lower aldehyde concentrations and have milder hangovers. The rate of detoxification of alcohol can also be slowed by certain drugs which interfere with the action of alcohol dehydrogenases, notably aspirin, furfural (which may be found in fusel alcohol), fumes of certain solvents, many heavy metals, and some pyrazole compounds. Also suspected of having this effect are cimetidine, ranitidine, and acetaminophen (paracetamol).
An "abnormal" liver with conditions such as hepatitis, cirrhosis, gall bladder disease, and cancer is likely to result in a slower rate of metabolism. People under 25 and women may process alcohol more slowly.
Food such as fructose can increase the rate of alcohol metabolism. The effect can vary significantly from person to person, but a 100 g dose of fructose has been shown to increase alcohol metabolism by an average of 80%. In people with proteinuria and hematuria, fructose can cause falsely high BAC readings, due to kidney-liver metabolism.
First-pass metabolism
During a typical drinking session, approximately 90% of the metabolism of ethanol occurs in the liver. Alcohol dehydrogenase and aldehyde dehydrogenase are present at their highest concentrations (in liver mitochondria). But these enzymes are widely expressed throughout the body, such as in the stomach and small intestine. Some alcohol undergoes a first pass of metabolism in these areas, before it ever enters the bloodstream.
In alcoholics
Under alcoholic conditions, the citric acid cycle is stalled by the oversupply of NADH derived from ethanol oxidation. The resulting backup of acetate shifts the reaction equilibrium for acetaldehyde dehydrogenase back towards acetaldehyde. Acetaldehyde subsequently accumulates and begins to form covalent bonds with cellular macromolecules, forming toxic adducts that, eventually, lead to death of the cell.
This same excess of NADH from ethanol oxidation causes the liver to move away from fatty acid oxidation, which produces NADH, towards fatty acid synthesis, which consumes NADH. This consequent lipogenesis is believed to account largely for the pathogenesis of alcoholic fatty liver disease.
In human fetuses
In human embryos and fetuses, ethanol is not metabolized via ADH as ADH enzymes are not yet expressed to any significant quantity in human fetal liver (the induction of ADH only starts after birth, and requires years to reach adult levels). Accordingly, the fetal liver cannot metabolize ethanol or other low molecular weight xenobiotics. In fetuses, ethanol is instead metabolized at much slower rates by different enzymes from the cytochrome P-450 superfamily (CYP), in particular by CYP2E1. The low fetal rate of ethanol clearance is responsible for the important observation that the fetal compartment retains high levels of ethanol long after ethanol has been cleared from the maternal circulation by the adult ADH activity in the maternal liver. CYP2E1 expression and activity have been detected in various human fetal tissues after the onset of organogenesis (ca 50 days of gestation). Exposure to ethanol is known to promote further induction of this enzyme in fetal and adult tissues. CYP2E1 is a major contributor to the so-called Microsomal Ethanol Oxidizing System (MEOS) and its activity in fetal tissues is thought to contribute significantly to the toxicity of maternal ethanol consumption. In presence of ethanol and oxygen, CYP2E1 is known to release superoxide radicals and induce the oxidation of polyunsaturated fatty acids to toxic aldehyde products like 4-hydroxynonenal (HNE).
The concentration of alcohol in breast milk produced during lactation is closely correlated to the individual's blood alcohol content.
Elimination
Alcohol is removed from the bloodstream by a combination of metabolism, excretion, and evaporation. 90-98% of ingested ethanol is metabolized into carbon dioxide and water. Around 5 to 10% of ethanol that is ingested is excreted unchanged in urine, breath, and sweat. Transdermal alcohol that diffuses through the skin as insensible perspiration or is exuded as sweat (sensible perspiration) can be detected using wearable sensor technology such as SCRAM ankle bracelet or the more discreet ION Wearable. Ethanol or its metabolites may be detectable in urine for up to 96 hours (3–5 days) after ingestion.
Unlike most physiologically active materials, in typical recreational use, ethanol is removed from the bloodstream at an approximately constant rate (linear decay or zero-order kinetics), rather than at a rate proportional to the current concentration (exponential decay with a characteristic elimination half-life). This is because typical doses of alcohol saturate the enzymes' capacity. In Widmark's model, the elimination rate from the blood, , contributes 60% of the uncertainty. Similarly to , its value depends on the units used for blood. varies 58% by occasion and 42% between subjects; it is thus difficult to determine precisely, and more practical to use a mean and a range of values. Typical elimination rates range from 10 to 34 mg/dL per hour, with Jones recommending the range 0.10 - 0.25 g/L/h for forensic purposes, for all subjects. Earlier studies found mean elimination rates of 15 mg/dL per hour for men and 18 mg/dL per hour for women, but Jones found 0.148 g/L/h and 0.156 g/L/h respectively. Although the difference between sexes is statistically significant, it is small compared to the overall uncertainty, so Jones recommends using the value 0.15 for the mean for all subjects. This mean rate is very roughly 8 grams of pure ethanol per hour (one British unit). Explanations for the gender difference are quite varied and include liver size, secondary effects of the volume of distribution, and sex-specific hormones. A 2023 study using a more complex two-compartment model with M-M elimination kinetics, with data from 60 men and 12 women, found statistically small effects of gender on maximal elimination rate and excluded them from the final model.
At concentrations below 0.15-0.20 g/L, alcohol is eliminated more slowly and the elimination rate more closely follows first-order kinetics. The overall behavior of the elimination rate is described well by Michaelis–Menten kinetics. This change in behavior was not noticed by Widmark because he could not analyze low BAC levels. The rate of elimination of ethanol is also increased at very high concentrations, such as in overdose, again more closely following first-order kinetics, with an elimination half-life of about 4 or 4.5 hours (a clearance rate of approximately 6 L/hour/70 kg). This is thought to be due to increased activity of CYP2E1.
Eating food in proximity to drinking increases elimination rate significantly, mainly due to increased metabolism.
Modeling
In fasting volunteers, blood levels of ethanol increase proportionally with the dose of ethanol administered. Peak blood alcohol concentrations may be estimated by dividing the amount of ethanol ingested by the body weight of the individual and correcting for water dilution. For time-dependent calculations, Swedish professor Erik Widmark developed a model of alcohol pharmacokinetics in the 1920s. The model corresponds to a single-compartment model with instantaneous absorption and zero-order kinetics for elimination. The model is most accurate when used to estimate BAC a few hours after drinking a single dose of alcohol in a fasted state, and can be within 20% CV of the true value. It is less accurate for BAC levels below 0.2 g/L (alcohol is not eliminated as quickly as predicted) and consumption with food (overestimating the peak BAC and time to return to zero).
See also
Subjective response to alcohol
References
5-HT3 agonists
AMPA receptor antagonists
Adenosine reuptake inhibitors
Alcohol abuse
Alcohol and health
Alcohol dehydrogenase inhibitors
Alcohol law
Alcohols
Analgesics
Anaphrodisia
Anxiolytics
Calcium channel blockers
Depressogens
Diuretics
Drugs acting on the nervous system
Drugs with unknown mechanisms of action
Emetics
Ethanol
Euphoriants
GABAA receptor positive allosteric modulators
General anesthetics
Glycine reuptake inhibitors
Hepatotoxins
Human metabolites
Hypnotics
IARC Group 1 carcinogens
Kainate receptor antagonists
NMDA receptor antagonists
Neurotoxins
Nicotinic agonists
Ototoxicity
Psychoactive drugs
Sedatives
Teratogens | Pharmacology of ethanol | [
"Chemistry",
"Biology"
] | 8,193 | [
"Hypnotics",
"Behavior",
"Sleep",
"Neurochemistry",
"Psychoactive drugs",
"Teratogens",
"Neurotoxins"
] |
76,599,128 | https://en.wikipedia.org/wiki/Agglomerate%20%28steel%20industry%29 | Agglomerate is a material composed of iron oxides and gangue, roasted and sintered in an agglomeration plant. This product is obtained by burning coal previously mixed with iron ore and oxides. This conditioning of iron ore optimizes its use in the blast furnace.
History
The advantages of agglomeration were identified very early on, but the processes used at the time were not continuous. The primitive method, which consisted of a grindstone grate, was abandoned towards the end of the 19th century because it was too fuel-intensive. Shaft furnaces then replaced them, their much higher efficiency being due both to the confinement of the reaction and to counter-current operation (the solids sink and the gases rise).
In these furnaces, iron ores were roasted to obtain the opposite result to the one we're looking for now: in 1895, roasting was carried out at low temperatures to avoid aggregation, and to obtain friable ore.
At the time, ore roasting furnaces were tanks inspired by blast furnaces and lime kilns, and were not very productive tools. Around 1910, the Greenawald process, which automated the principle3, saw some development, enabling the production of 300,000 tonnes a year.
In June 1906, A.S. Dwight and R. L. Lloyd built the first agglomerating machine on a chain (also known as a grate), which began agglomerating copper and lead ores. The first agglomeration line for iron ores was built in 1910 in Birdsboro, Pennsylvania.
It took some thirty years for the sintering of ores on chains to become widespread in the steel industry. Whereas before the Second World War, it was mainly used for reconditioning ore fines, after 1945 it became widespread for processing raw ores. Today, it plays an essential role in the blending of different ores and, above all, in the incorporation of mineral wastes of varying iron content. This recycling role improves profitability and limits the amount of waste generated by steel complexes, which generate numerous iron-rich residues (slag, sludge, dust, etc.).
Interests and limitations
Interests
Chipboard is a product optimized for use in blast furnaces. To do so, it must meet several conditions:
be composed of a gangue of oxides which, combined with the ash from coke combustion (essentially silica), will give rise to a fusible slag which is both reactive towards impurities (in particular the sulfur provided by the coke), not very aggressive towards the refractories lining the blast furnace and of a quality suitable for its use;
Ensure a precise particle size, generally between 20 and 80 mm (pieces that are too small clog up the furnace, and pieces that are too large take too long to transform in the core);
maintain permeability to reducing gases at the highest possible temperatures;
low-temperature endothermic reactions that can be carried out more economically outside a blast furnace. These are essentially drying, calcination of the gangue (decarbonisation of limestone and dehydration of clay or gypsum), and reduction reactions. The agglomerate then becomes, at equal weight, richer in iron than the ore.
over oxidize iron oxides, Fe2O3 being better reduced by the carbon monoxide present in the blast furnace than less oxidized compounds, especially Fe3O4.
Another advantage is the elimination of undesirable elements: the chain agglomeration process eliminates 80-95% of the sulfur present in the ore and its additives. It's also a way of getting rid of zinc, the element that "poisons" blast furnaces, as its vaporization temperature of 907°C corresponds to that of a well-conducted roast.
Limitations
On the other hand, agglomerate is an abrasive product that damages blast furnace vessels, especially if these are not designed for absorber, and is above all fragile. Repeated handling degrades its grain size and generates fines, making it unsuitable for packaging at sites far from blast furnaces: pellets are therefore preferable. Cold resistance, particularly to crushing, can be improved by increasing the energy input during sintering.
Improving mechanical strength also improves the performance of agglomerates in the processes that use them. The reduction of hematite (Fe2O3) to magnetite (Fe3O4) creates internal stresses. However, in addition to increasing the cost of agglomerate production, reducibility deteriorates when mechanical strength is sought.
Composition
Agglomerates are generally classified as acidic or basic. The complete basicity index ic is calculated by the following ratio of mass concentrations:
It is often simplified by simply calculating a simplified basicity index noted i (or sometimes ia), equal to the ratio CaO / SiO2. An agglomerate with an index ic of less than 1 is said to be acidic; above 1, it is generally said to be basic; equal to 1, it is said to be self-melting (ic=1 being equivalent to ia=1.40). Before the 1950s, agglomerates with an ic value of less than 0.5 were in the majority. Then, when it was realized that agglomerate could incorporate limestone, which was then charged into the blast furnace separately, basic indices became widespread: in 1965, indices below 0.5 represented less than 15% of the tonnage of agglomerate produced, while basic agglomerates accounted for 45%.
Again, we find the relationship: k being an empirically determined constant (sometimes equal, for simplicity, to 1). Iron reduction is, in itself, favored by a basic environment, and peaks at 2<ib<2.5. It is also in this range that mechanical strength is best (and also, the slag's fusibility is the worst, which complicates its removal from the blast furnace). Above an ib value of 2.6, the proportion of molten agglomerate increases, clogging the pores and slowing down chemical reactions between gases and oxides. As for acid agglomerates with an ib index of less than 1, softening begins as soon as only around 15% of the ore has been reduced.
The optimum basicity index is therefore determined according to the ore used, the technical characteristics of the blast furnace, the intended use of the cast iron and the desired qualities. For example:
Cast irons made from Minette (ore) and intended for refining using the Thomas process had basicities of i=1.35 (a complete index I=1), which was a compromise between low-temperature viscosity (which requires an acidic slag) and desulfurization (favored by a basic slag);
plants for which sulfur-rich cast iron is not a problem adopt a more acidic agglomerate: with i= 0.9 to 1.0. This favors silicon reduction but can result in very high sulfur contents, from 0.1 to 0.25%;
the production of ferromanganese in the blast furnace requires a high manganese yield and therefore high basicities, up to i = 1.7 or 1.8 (bearing in mind that in this particular case, the index corresponds to !). Meltability is a secondary consideration in this case, as slag temperatures can reach 1,650°C (instead of 1,450°C - 1,550°C in the production of cast irons for refining).
See also
Speiss
Sinter plant
Agglomerate
Pellet (steel industry)
References
Bibliography
Notes
Metallurgy
Minerals
Steel industry | Agglomerate (steel industry) | [
"Chemistry",
"Materials_science",
"Engineering"
] | 1,602 | [
"Metallurgy",
"Materials science",
"nan"
] |
76,599,574 | https://en.wikipedia.org/wiki/RG/RGG%20motif | The arginine-glycine or arginine-glycine-glycine (RG/RGG) motif is a repeating amino acid sequence motif commonly found in RNA-binding proteins (RBPs). RGG regions in proteins are defined as two or more RG/RGG sequences within a stretch of 30 amino acids. Initially named the RGG box, it confers a protein with the ability to bind double-stranded mRNA molecules. The RGG motif has been observed in proteins from at least 12 animal species, including humans.
Biochemical function
RGG motifs are primarily involved in mediating protein-RNA interactions. Positive charges from arginine residues promote electrostatic interactions with mRNA molecules. The composition and structure of the arginine side chain may also allow for specific interactions with other molecules as opposed to the other positively charged amino acids, lysine and histidine. Glycine residues add flexibility to the peptide structure and promote their tendency to form intrinsically disordered regions. The RGG motif can also drive liquid-lipid phase separation of proteins inside cells as well as in vitro.
Synthetic uses
Researchers have pursued creating condensates with novel functions for use in cellular and metabolic engineering. Synthetically designed proteins containing repeating RGG motifs have been used to form droplets with tunable properties in cells and in vitro.
Notable RGG-containing proteins
RGG motif-containing proteins are the second most abundant group of RBPs in the human genome. They are involved in various RNA metabolism, export, and translation functions.
Sbp1
Npl3
Ded1
FMR1
FUS
Laf-1
References
Bioinformatics | RG/RGG motif | [
"Engineering",
"Biology"
] | 339 | [
"Bioinformatics",
"Biological engineering"
] |
76,599,980 | https://en.wikipedia.org/wiki/Bierlein%27s%20measure%20extension%20theorem | Bierlein's measure extension theorem is a result from measure theory and probability theory on extensions of probability measures. The theorem makes a statement about when one can extend a probability measure to a larger σ-algebra. It is of particular interest for infinite dimensional spaces.
The theorem is named after the German mathematician Dietrich Bierlein, who proved the statement for countable families in 1962. The general case was shown by Albert Ascherl and Jürgen Lehn in 1977.
A measure extension theorem of Bierlein
Let be a probability space and be a σ-algebra, then in general can not be extended to . For instance when is countably infinite, this is not always possible. Bierlein's extension theorem says, that it is always possible for disjoint families.
Statement of the theorem
Bierlein's measure extension theorem is
Let be a probability space, an arbitrary index set and a family of disjoint sets from . Then there exists a extension of on .
Related results and generalizations
Bierlein gave a result which stated an implication for uniqueness of the extension. Ascherl and Lehn gave a condition for equivalence.
Zbigniew Lipecki proved in 1979 a variant of the statement for group-valued measures (i.e. for "topological hausdorff group"-valued measures).
References
Theorems in measure theory
Probability theorems | Bierlein's measure extension theorem | [
"Mathematics"
] | 283 | [
"Theorems in mathematical analysis",
"Theorems in measure theory",
"Theorems in probability theory",
"Mathematical problems",
"Mathematical theorems"
] |
76,600,047 | https://en.wikipedia.org/wiki/Depublizieren | Depublizieren is the process of removing websites from publicly accessible areas, which the online services (Telemedia) of the public broadcasters in Germany began in the summer of 2009 for their archive holdings and, since September 1, 2010, also for current reporting after a period of generally seven days. Websites that have been removed by the Interstate Broadcasting Agreement (RStV) do not have to be deleted but are no longer publicly accessible.
According to ARD, Germany's process for depublizieren public service websites is the most complex in the world. Although the BBC has also reduced its online services to justify its license fee funding, the Public-Value-Test used in the UK - the model for the German three-step test - only applies to major projects. In contrast to the German broadcasters, the ORF refrains from a retrospective review of existing offerings. Estimates of the total volume of older public service Internet content that has been decommissioned are more than one million online documents.
The term "depublizieren" or "depublication" is also used when controversial or erroneous online content is removed from the publicly accessible area. It is also used for private media.
Concept
Depublizieren is a neologism from the word publication (publish, from Latin publicus, public) and the Latin prefix de- ("off", " gone", "down", "miss"). The term, which is not used on a legal basis, was hardly used before 2010. Earlier definitions of depublizieren as "unpublishing" referred to the removal of factually incorrect content from the Internet without comment instead of correction or, as a technical term, to the withdrawal of a contribution visible on a website without its deletion from the repository. Technically, the latter meaning corresponds to using the term in the discussion about depublishing public Internet content.
The formation of the term contains a paradoxical element, as the terms "publishing" or " publicizing" do not actually permit this form of formation of antonyms: a statement made to the public by publication cannot be retracted by not continuing to disseminate it, but only by revocating it. Therefore, a person harmed by untrue media reports can regularly assert a claim for a right of reply or rectification (→ right to rectification).
However, such a corrective revocation is not meant when depublishing public service content. The use of the term by the employees and committees of public broadcasters responsible for the organization of depublizieren made the term a buzzword in the summer of 2010, which, due to its contradictory nature, tends to criticize the removal of websites (→ Reactions section). What is published on the internet cannot be taken back; this is conceptually "silly" and a "fight against windmills" (Johnny Haeusler). Depublizieren was named early on as a possible un-word of the year 2010.
Previous history
In 2003, the German Association of Private Broadcasters and Telemedia (VPRT) filed a complaint with the European Commission, describing the broadcast receiving license as illegal state aid under Article
paragraph 1 of the Treaty of Rome (EGV) - now Article 107 paragraph 1 of the TFEU Treaty. This funding distorts competition and puts private companies at a disadvantage, especially since public broadcasters do not have a narrowly defined functional mandate for their activities, especially in the online sector. Although the federal states and the broadcasters themselves had never considered the financing of the fees as a state subsidy, the EU Commission followed the VPRT's interpretation and demanded that this aid be abolished or that the exemption criteria of Article
paragraph 2 of the Treaty of Rome (EGV) be fulfilled. An open conflict arose in the summer of 2007:
However, Article 5 of the Basic Law for the Federal Republic of Germany guarantees "freedom of the press and freedom of reporting through broadcasting and film", and although public service broadcasting is not explicitly mentioned there, this includes its reporting and press products. On September 11, 2007, the Federal Constitutional Court stated that the mandate of public service broadcasting also extends to new digital offerings and contains a "development guarantee" (already stated in earlier broadcasting rulings by the court). According to this, public service broadcasting is to ensure the diversity of offerings and the reliability of information on the internet - it is attributed a "genuine online mandate". "The Supreme Court's ruling on fees was seen as a victory for public service broadcasting."
The State Aid Compromise of 2007 between the Federal Republic of Germany and the EU Commission stipulated that "the functional mandate of the public broadcasters will be sufficiently specified" by June 1, 2009, and in particular that its extension to online offerings will be defined. This compromise averted a case before the European Court of Justice, which could have "called into question the financing of broadcasting in the entire EU".
Legal basis
Objective
On June 1, 2009, the 12th Amendment to the Interstate Broadcasting Treaty (12th RÄStV) came into force, with which the federal states wanted to fulfill their obligations from the State Aid Compromise and at the same time secure the constitutionally guaranteed independence of the public media.
The 12th Interstate Broadcasting Treaty (RÄStV) should fully transfer the traditional mission of the public broadcasters to the online sector, as the "density of households that are technically connected to the Internet and use Internet services" has increased considerably and the development guarantee confirmed by the Federal Constitutional Court requires this. To meet the requirements of the EU Commission, however, one aspect in particular must be taken into account:
Broadcasting concept
However, the 12th RÄStV also included a change to the definition of broadcasting. Section 2, paragraph 1, of the new RStV now states:
According to the explanatory memorandum of the 12th Interstate Broadcasting Treaty, the new aspect is "the clarification that broadcasting is a linear information and communication service. The insertion of the criterion 'for simultaneous reception' distinguishes broadcasting services from on-demand services. Simultaneous reception is also to be understood as a transmission which is subject to short delays for technical reasons alone". The linearity criterion excludes, for example, the independent presentation of user-generated content and the form of an online community. The exclusion of on-demand offerings is the basis for the definition of dwell times for public Internet offerings (→ section Dwell times). Without the broad understanding of "simultaneous", which allows for short delays "for technical reasons", this redefinition would not allow public service content to be accessed over the Internet.
In the 12th version of the RStV, which has been in force since 2009, public broadcasters are no longer allowed to offer "non-broadcast press-like offerings" and "comprehensive local reporting" according to Section 11d. This paragraph also includes an addendum with various forms of offerings that are not permitted for the online presence of public broadcasters, including, for example, file-sharing platforms, route planners, and classified ads.
Dwell times
On December 18, 2008, the state governments agreed in the 12th RÄStV that broadcasters may normally make program-related content available for seven days. According to Section 11d, Paragraph 2, RStV, exceptions apply, among other things, to soccer coverage of 1st and 2nd Bundesliga matches, which may only be available for 24 hours, and to archives "with contemporary and cultural history content", which may be online for an unlimited period.
According to the explanatory memorandum of the 12th RÄStV, "the provision of contemporary and cultural history content in the form of Telemedia corresponds to the democratic, social and cultural needs of society". The restriction of soccer coverage is justified with "higher costs for the acquisition of additional rights" for a longer on-demand option, which "should be avoided in the interest of the license fee payers".
To meet the requirements of the EU Commission about the specification of their functional mandate without interfering with their constitutional independence, the federal states prescribed the three-step test as a procedure for the public broadcasters to check the conformity of the offer with the mandate in each case. However, the decision on the continuation of old offers and the introduction of new concepts on the Internet and in broadcasting was left to the broadcasting bodies themselves, the Broadcasting Councils. These bodies also decide on the duration of online services.
Procedure
Three-step test
Accordingly, the competent Broadcasting Councils (Television Council, Radio Council) decide in a five-stage procedure whether or not an offer meets the three-stage test criteria, namely
If a Broadcasting Board determines that an offering is new or substantially changed and is neither already legally required nor already legally prohibited (Phase 1), it initiates the procedure (Phase 2) based on a specific description of the offering, the central element of which is the collection of information (Phase 3), on which the Broadcasting Board's decision, including the statement of reasons (Phase 4), and the final review by the responsible state government as the legal supervisor (Phase 5) are based.
The information gathering phase includes, in particular, obtaining the views of competing suppliers and the views of independent experts on the impact of the proposed transaction on competition. Comments and economic data from private competitors (which are taken into account in the procedure but are not published) could, for example, state that "offers already on the market will be completely crowded out", which would affect the second three-step test criterion. However, according to the three-step test, the determination of the "democratic, social and cultural needs of society" and the quality of a service in terms of journalistic competition are also important elements in answering the question of whether or not a specific service falls within the remit of public service broadcasting. Only after all of this has been weighed against the costs of a service can a broadcasting council decide on the admissibility of an offer, justify its decision and pass it on to the respective state government responsible for legal supervision: The legal supervision checks compliance with the procedural rules, but does not make its assessment of the content (otherwise it would be a constitutionally inadmissible "technical supervision" in the broadcasting sector).
The results of the subsequent three-stage tests for the existing offerings were published in summer 2010. Saarland Broadcasting, among others, summarized the considerations on media use on which its dwell time concept was based:
Because of this distinction between two usage patterns, public broadcasters typically make a large portion of their online offerings available for seven days (lean-back approach) and another portion for a longer period, such as a year (lean-forward approach).
Reactions
Following the adoption of the 12th RÄStV, there were several media debates in 2009 and 2010 about the three-step tests and the resulting restrictions on public online offerings. Private media companies and publishers' associations were less critical of ZDF than of ARD, which is much more complexly organized with a total of 37 three-stage tests. During this period, representatives of public and private media often met in panel discussions. The new legal regulations were criticized with combative terms such as "Morgenthau Plan" or "censorship", while private publishers often used the catchword "electronic press" for the online offerings of the broadcasters.
After the completion of the Telemedia concepts in the summer of 2010, the length of time that various television genres remained in the media libraries and the deletion of online contributions became much-discussed topics "that arouse the ire of Internet users and are ostentatiously regretted by those responsible at the broadcasters. Like some ARD broadcasters, ZDF announced the removal of about 80 percent of its online content, which it estimated at 93,500 individual documents. ZDF director-general Markus Schächter said he hoped this would put an end to the debate about public broadcasters' online activities:
Some politicians are also critical of depublizieren, with the SPD in Saarland and the Pirate Party in Brandenburg both rejecting it in their manifestos. In January 2013, the Internet and Digital Society Study Commission (EIDG) of the German Parliament, consisting of 17 experts and 17 members of parliament from all parties, explicitly recommended the abolition of the depublizieren obligation stipulated in the Interstate Broadcasting Treaty. Representatives of the governing coalition, however, only wanted the seven-day rule to be lifted for offerings that represent a "qualitative added value" compared to existing offerings from private providers.
Biased reports
When the first articles disappeared from their online offerings, the editorial teams of the public broadcasters were initially confronted with questions about the supposed deletion of websites. They used the term depublizieren to explain the process and to clarify the difference with the deletion of websites, and were confronted with critical opinions from the public, which had already been anticipated in public statements:
The coverage of the three-stage review process was so negative in the spring of 2010 that the Conference of Commission Chairmen of the Association of State Media Authorities felt compelled to complain about the poor quality of reporting. Among other things, "abbreviated, incorrect and one-sided" reports were made from confidential documents, giving "the impression that the committees are avoiding transparency in a quasi-autocratic and interest-driven manner. At the same time, however, the influence of lobbying by publishers and private broadcasters has already been pointed out, in whose interests the extensive curtailment of public service online activities is taking place, although they are not satisfied with the result. In the spring of 2010, media journalist Stefan Niggemeier drew attention to the conflict of interest between private media providers and public service media, which has led to biased reporting by both groups.
The most critical coverage of the depublizieren that began in the summer after the Telemedia concepts were decided on largely corresponded to the relationship of the depublizieren editors to their work, as Niggemeier made clear in one of the first newspaper reports entitled Depublizieren:
The public broadcasters' reporting therefore also expressed their dissatisfaction with the depublizieren process and referred to the broadcasters' legal obligation to do so. Following accusations by the BDZV that the depublizieren of ARD online content did not go far enough and was, therefore, a farce, ARD Chairman Peter Boudgoust summarized that ARD had depublished more than one million Internet pages, including around 80 percent of the original pages of tagesschau.de. ARD had not wanted this procedure, but had "complied with applicable law in its implementation". Unfortunately, it was "primarily the users who had to pay the price". In July 2010, at the same time as the decision-making phase for the Telemedia concepts, the now defunct website www.depublizieren.de was created as a protest against depublizieren, containing a fictitious death notice for "Die Publizierung".
Representatives of private media groups also expressed mild criticism of the three-step test, describing it as a "relatively pointless procedure". The removed content meant that "no publisher earned a single euro more". RTL Group announced that it was "still considering legal action against some online publications of ARD and ZDF".
Depub.org
The depublizieren of public Internet content received a new wave of public attention after the implementation of concepts developed for this purpose in September 2010: After an archive of tagesschau.de articles written between 1999 and 2010 had already been offered on the BitTorrent download portal The Pirate Bay in July 2010, the website depub.org put preparation of this archived content online for free retrieval on August 20, 2010, so that users could similarly access the articles to the version on tagesschau.de before depublication. The offer also included the function of continuously archiving current articles from tagesschau.de and making them available on depub.org. Thus, depub.org also acted as a mirror for some articles that had not yet been depublished by tagesschau.de.
Numerous German-language media reported on depub.org, especially from mid-September 2010, emphasizing that depub.org was "trying to get hold of the already deleted content of other public media" and relying on the help of their editors: "We are confident that there are also people in the other newsrooms who do not want the articles to disappear from the web." Robin Meyer-Lucht quoted an NDR spokesperson: "NDR will take legal action against Depub.org if possible. Indications of a possible unauthorized republication of depublished tagesschau.de content had already come from the editorial team itself in July 2010. Depub.org claimed to have asked the editorial team before republishing the tagesschau.de content. The response from the editorial team warned: "that an archive could affect the copyrights of third parties, such as agencies or photographers, and that it is therefore at our own risk to operate such an archive." According to the response, depub.org "has reason to believe that the Tagesschau.de editorial team has no major problems with the archive.
Zeit editor Kai Biermann described the depub.org campaign as civil courage in the "public interest," even though it was illegal. Depublication, on the other hand, is "an expression of the egoistic interests of private companies. Due to the method of "calculated law breaking for idealistic reasons", the depub.org activists were often accused of being "Robin Hoods".
Depub.org announced its intention to set up archives for the public Internet offerings br-online.de, hr-online.de, mdr.de, ndr.de, rbb-online.de, radiobremen.de, swr.de, wdr.de and heute.de. Publicly available articles would be stored for this purpose. For content that has already been published, however, the company relies on editors to provide archive data.
Dagmar Gräfin Kerssenbrock, a CDU politician from Schleswig-Holstein and chairwoman of the NDR broadcasting council, called depub.org "an example of the creative anarchy on the Internet" and of the great interest in the content of tagesschau.de. Therefore, "there will always be people who find a way to make this content available. Sites like depub.org are proof of the dubious nature of the three-step test. The Tagesschau online editorial team suspects that the contents of the anonymously registered domain depub.org in Canada were collected while the articles, which have now been published, were still publicly accessible. However, according to tagesschau.de editor-in-chief Jörg Sadrozinski, the illegal use of tagesschau.de articles by depub.org could lead to "politicians or lobbyists in publishing houses realizing that such measures are simply pointless, that the Internet never forgets".
When the depub.org domain became unavailable in mid-October 2010, the service moved to depub.info for a short time. However, this site was soon unavailable as well. Between November 10, 2010, and July 13, 2011, when a Twitter message was sent to the tagesschau.de archive, there were no public messages from the depub.org activists.
Evaluation & Berlin requirements 2014
On July 1, 2014, the Berlin House of Deputies called on the Senate to review the practice, which had been in place for five years, and to abolish the obligation to depublish.
Netzpolitik.org reported in 2017 that it was "difficult to explain to viewers why contributions financed by the general public should not be permanently available". The vast majority of federal states are in favor of abolition.
Reform concept of the ZDF
Since May 2019, public broadcasters have been allowed to develop new digital offerings, provided they are based on a concept approved by the supervisory bodies.
The ZDF presented a reform concept for this in 2019. According to this concept, contemporary and cultural history archives with informative, educational, and cultural telemedia will be offered for an unlimited period. On the other hand, educational content from the fields of science, technology, theology or ethics, political education, the environment, work, and social affairs, as well as cultural content that documents cultural achievements in their social context, will be discontinued after five years.
A total of 17 comments were received by the deadline of October 28. In a joint open letter to the ZDF Television Council, the GEW trade union, the German Library Association, and Wikimedia, among others, called for a rethink. This reform concept would not do justice to "the important role of public broadcasting in the German educational landscape of the 21st century".
References
External links
Dreistufentest (Memento from February 8, 2011, in the Internet Archive) In: ARD.de.
Daniel Bouhs: Die digitale Schranke. In: Zeit online, November 4, 2017, retrieved on November 4, 2017
Stefan Niggemeier: Depublizieren. Die Leere hinter dem Link. In: FAZ.net, July 19, 2010, retrieved on September 15, 2010.
Jörg Sadrozinski: Depublizieren (Memento from July 23, 2010, in the Internet Archive). In: blog.tagesschau.de, July 20, 2010, accessed September 15, 2010.
Maik Gizinski: Das Löschen von Internet-Archiven (Memento from September 10, 2010, in the Internet Archive). In: Zapp (NDR Fernsehen), September 8, 2010 (Video, 7:38 minutes), retrieved on September 15, 2010.
Maik Gizinski: Der Kampf der Netzaktivisten gegen das Depublizieren. In: Zapp (NDR Fernsehen), September 22, 2010 (Video, 7:11 minutes), retrieved on September 25, 2010.
Online journalism
Computer law
Political communication | Depublizieren | [
"Technology"
] | 4,600 | [
"Computer law",
"Computing and society"
] |
76,600,617 | https://en.wikipedia.org/wiki/Xiaoying%20Zhuang | Xiaoying Zhuang (born 1983) is a researcher in computational mechanics, including continuum mechanics, peridynamics, and the analysis of vibration and fracture mechanics. She has applied these methods in the design of composite materials and nanostructures, including materials for the aerospace industry and nano-machines for harvesting vibrational energy. Originally from China, and educated in China and England, she has worked in Norway, China, and Germany, where she is Heisenberg Professor and Chair of Computational Science and Simulation Technology of Leibniz University Hannover.
Education and career
Zhuang was born in Shanghai in 1983. She was a student at Tongji University in Shanghai, graduating in 2007, and then traveled to Durham University in England for graduate study. She completed her doctoral dissertation, Meshless methods: theory and application in 3D fracture modelling with level sets, in 2010 in the Durham School of Engineering and Computing Sciences, supervised by Charles Augarde.
She became a postdoctoral researcher at the Norwegian University of Science and Technology, and then from 2011 to 2014 she returned to Tongji University as a lecturer and later associate professor.
She moved to Germany in 2014. After a year at Bauhaus University, Weimar, she became a research group leader within the Institute of Continuum Mechanics at Leibniz University Hannover in Germany in 2015. She became a full professor at the university in 2021; there, she is a Heisenberg Professor and Chair of Computational Science and Simulation Technology in the Institute for Photonics and Faculty of Mathematics and Physics.
Books
Zhuang is a coauthor of books including:
Extended Finite Element and Meshfree Methods (with Timon Rabczuk, Jeong-Hoon Song, and Cosmin Anitescu, Academic Press, 2020)
Computational Methods Based on Peridynamics and Nonlocal Operators: Theory and Applications (with Timon Rabczuk and Huilong Ren, Springer, 2023).
Recognition
The Association of Computational Mechanics in Engineering – UK (ACME-UK) gave Zhuang their 2010 Zienkiewicz Prize for the best annual doctoral dissertation in computational mechanics. Zhuang's move to Bauhaus University, Weimar was funded by a Marie Curie International Incoming Fellowship, funded by the European Commission. She was a 2015 recipient of the Sofia Kovalevskaya Award, funding her work as a group leader in the Hannover Institute of Continuum Mechanics.
Zhuang was a 2018 recipient of the Heinz Maier-Leibnitz-Preis, given "for her research into lightweight materials for aviation". The International Chinese Association of Computational Mechanics gave her their Fellow Award in 2018, and she was also a 2018 recipient of the Science Prize of the State of Lower Saxony for Young Scientists. She was a 2019 recipient of the German Curious Mind Researcher Award, in the "materials and active ingredients" category, recognizing her research on the simulation of nano-scale mechanical-energy harvesters "at the intersection of mechanical engineering and materials science". She was named as a Heisenberg Professor in 2020.
References
External links
1983 births
Living people
Engineers from Shanghai
Chinese mechanical engineers
German mechanical engineers
Women mechanical engineers
Chinese materials scientists
German materials scientists
Women materials scientists and engineers
Chinese nanotechnologists
German nanotechnologists
Tongji University alumni
Alumni of Durham University
Academic staff of Tongji University
Academic staff of the University of Hanover | Xiaoying Zhuang | [
"Materials_science",
"Technology"
] | 675 | [
"Women materials scientists and engineers",
"Materials scientists and engineers",
"Women in science and technology"
] |
76,600,832 | https://en.wikipedia.org/wiki/Shannon%20Launch%20and%20Recovery%20System | Shannon Launch and Recovery System (SLARS) is a custom designed tractor and trailer specifically designed for the Royal National Lifeboat Institution (RNLI) to launch and recover lifeboats.
The SLARS is produced by two British companies, Supacat, based in Honiton, Devon, and Clayton Engineering Limited, based in Knighton, Powys. In 2015, Supacat rebranded as SC Innovation.
Operation
The Shannon launch and recovery system (SLARS) was developed to launch and recover the 18-tonne RNLI lifeboat.
The lifeboat is launched, and recovered, bow-first. The carriage, mounted on tracked wheels, is used to transport a lifeboat from boathouse to sea. The carriage can then be tilted, effectively acting as a slipway to launch the boat when released.
On return, the boat will be driven ashore. A synthetic winch line, designed not to recoil should it break, is attached to the bow of the lifeboat, and the carriage is again tilted to meet the bow of the boat. The lifeboat is then hauled up the carriage. When the carriage is returned to the horizontal, and the lifeboat securely attached, the top section of the carriage rotates 180° as a turntable, and the lifeboat is ready to relaunch.
Both the tractor and carriage are tracked vehicles. In some locations, the carriage is also a powered unit, to assist traction and movement. The driver has two sets of controls, and can rotate the seat 180°. The high cab gives excellent visibility, with CCTV to assist. The cab is fully waterproof, and the vehicle can be operated in of calm water.
RNLI SLARS Fleet
See also
Shannon-class lifeboat
Talus MB-H amphibious tractor
Talus MB-764 amphibious tractor
RNLI New Holland TC45 launch tractor
Talus Atlantic 85 DO-DO launch carriage
References
Royal National Lifeboat Institution launch vehicles
Sea-going tractors
Tractors
Rescue equipment | Shannon Launch and Recovery System | [
"Engineering"
] | 388 | [
"Engineering vehicles",
"Tractors"
] |
67,840,660 | https://en.wikipedia.org/wiki/NGC%201351 | NGC 1351 is a lenticular galaxy in the constellation Fornax. It has a redshift of z=0.00505, and its distance from Earth can be estimated as 21 million parsecs (68 million light-years). It is elongated in shape, and was discovered by John Herschel on October 19, 1835.
The diameter of the galaxy is about 33 kpc, which makes it a medium-size galaxy, and smaller than the Milky Way. It is a member of the Fornax Cluster, a cluster of approximately 200 galaxies. The galaxy possesses a bright nucleus at its center.
It is currently receding from the solar system at a velocity of 1514 km/s, and 1410 km/s from the cosmic microwave background.
See also
NGC 1399
NGC 1365
References
Elliptical galaxies
013028
Fornax
1351 | NGC 1351 | [
"Astronomy"
] | 178 | [
"Fornax",
"Constellations"
] |
67,840,990 | https://en.wikipedia.org/wiki/Fiesselmann%20thiophene%20synthesis | The Fiesselmann thiophene synthesis is a name reaction in organic chemistry that allows for the generation of 3-hydroxy-2-thiophenecarboxylic acid derivatives from α,β-acetylenic esters with thioglycolic acid and its derivatives under the presence of a base. The reaction was developed by Hans Fiesselmann in the 1950s.
Mechanism
After deprotonation the thioglycolic acid ester attacks the tripel bond of the alkyne. Another addition takes place on the resulting double bond. Via deprotonation of a thioglycolic acid ester moiety the cyclization is initialized. From the resulting thiolane an alcoholate is eliminated to yield a ketone. Elimination of a thioglycolic acid ester results in an α,β-unsaturated ketone. Tautomerization leads to the desired product.
Applications
A variation of the Fiesselmann synthesis by Lissavetzky starts from a cyclic β-ketoester and thioglycolic acid. In combination with an alcohol (R4OH) the monoadduct is the main product. Without the addition of alcohol a thioacetal is generated. In presence of potassium hydroxide it can be esterificated and cyclisized. To cyclisize the mono adduct a sodium alcoholate is used.
If the substrate contains a nitrile instead of an ester group the reaction will result in 3-aminothiophenes. Scott used this approach to synthesis a p38 kinase inhibitor.
The reaction also works with aromatic derivates. Fry used this variation for the synthesis of tyrosinkinase inhibitors, starting from a substituted pyridine.
Nicolaou used the conditions of the Fiesselmann thiophene synthesis to show potential DNA cleaving properties of golfomycin A, a cyclic alkyne with potential antitumor activity. The Fiesselmann synthesis is also used to produce potential antiallergy agents, antileishmanial and antifungal agents and thieno[b]azepinediones.
References
Name reactions
Sulfur heterocycle forming reactions | Fiesselmann thiophene synthesis | [
"Chemistry"
] | 461 | [
"Name reactions",
"Ring forming reactions",
"Organic reactions"
] |
67,841,213 | https://en.wikipedia.org/wiki/Cross-browser%20testing | Cross-browser testing is a type of non-functional software testing where web applications are checked for support across different browsers and devices. Cross-browser testing can also provide an objective, independent view of the status of the web application to allow the business to appreciate and understand the risks of releasing it or implementing new feature(s). Test techniques include the process of executing a web application with the intent of finding failures in different browsers and devices and verifying that the website is fit for use in all of them. In other words, Cross-browser testing is verification that web application behaves in various web browsers identically
History
The term "cross-browser testing" originated in the early 2000s with the advent of various web browsers that rendered web pages in different ways and supported different web technologies. As a result, this led to inconsistencies in the behavior of web applications across browsers. In the early 2010s, smartphones entered the device market, and their number began to grow significantly. According to the data from Statcounter, in November 2016 the number of sessions on mobile devices equaled the number of sessions on desktop devices. As of July 2021, the number of sessions on mobile devices is already 55.4%. The widespread use of mobile devices has led to the emergence of the term "cross-device testing"
Cross-browser testing process
Cross-browser testing involves the execution of a web application to evaluate one or more properties of interest on different browsers and devices. In general, these properties indicate the extent to which the web application under test:
meets the requirements that guided its design and development,
responds correctly to all kinds of inputs,
performs its functions within an acceptable time,
is sufficiently usable,
can be installed and run in its intended web browsers and devices
achieves the general result its stakeholders desire.
QA engineers
Cross-browser testing is usually performed by QA engineers. After the development team builds a web application or site, QA engineers evaluate the completed project. The QA engineer tests the consistency of the content and layout, such as how fonts and images display, and whether the responsive web design works, if applicable. Next, they check the web application or site's usability, such as features, integrations with third-party services, forms, and touch input for mobile or tablets. They also test accessibility, such as the presence of alt text for images or closed captioning for video.
Web developers
Cross-browser testing can be conducted even if the web application is partially complete. With such an approach, also called "Full-stack web development", cross-browser tests are performed by web developers as they develop elements of the user interface and functionalities.
References
Software testing
Web browsers | Cross-browser testing | [
"Engineering"
] | 557 | [
"Software engineering",
"Software testing"
] |
67,841,351 | https://en.wikipedia.org/wiki/Dibutylmagnesium | Dibutylmagnesium is an organometallic chemical compound of magnesium. Its chemical formula is . Dibutylmagnesium is a chemical compound from the group of organomagnesium compounds. The pure substance is a waxy solid. Commercially, it is marketed as solution in heptane.
Synthesis
Dibutylmagnesium can be obtained by reaction of butyllithium with magnesium butylchloride and subsequent addition of magnesium 2-ethylhexanoate. The compound can also be prepared by hydrogenation of magnesium, followed by reaction with 1-butene. It is also possible to prepare dibutylmagnesium using 2-chlorobutane, magnesium powder, and n-butyllithium.
Use
Dibutylmagnesium is used as a convenient reagent for the preparation of organomagnesium compounds.
References
Magnesium compounds
Organomagnesium compounds
Butyl compounds
Pyrophoric materials | Dibutylmagnesium | [
"Chemistry",
"Technology"
] | 208 | [
"Organomagnesium compounds",
"Reagents for organic chemistry"
] |
67,842,407 | https://en.wikipedia.org/wiki/Irish%20Steel | Irish Steel Limited (), later known as Irish Ispat Limited, was an Irish semi-state company which was involved in steel production primarily from a plant on Haulbowline island in Cork Harbour. Originally founded in 1939, the company and its assets were sold to Ispat International (later known as Mittal Steel Company) (for IR£1) in 1996. The company and its plant closed down in 2001.
Dumping of production materials, including toxic waste, resulted in significant contamination of the Irish Steel plant site, and increased the size of Haulbowline island by . Campaigners, including Erin Brockovich, pushed for action by the state, and €61m was allocated to clean-up the site and to redevelop it as a park. The cleanup and redevelopment project lasted upwards of a decade; from 2011 to 2021.
History
Irish Steel was originally formed as a privately owned firm in 1939, and commenced operations from a steel plant on Haulbowline island, near Cobh in Cork Harbour. This company went into receivership in the 1940s, and in 1947 the then Minister for Industry and Commerce, Seán Lemass, established a state-financed company to acquire its assets and "secure 240 jobs".
In 1960, the state's involvement was expanded by the "Irish Steel Holdings Limited Bill (1960)", in what Jack Lynch (by then Minister for Industry and Commerce) described as addressing a "gap which would otherwise exist in [Ireland's] industrial capacity". By the late 1960s, Irish Steel was producing approximately one-third of steel used by Irish industry. At its peak, in 1971, the company employed approximately 1,200 people and had increased production to run 24-hours-a-day, seven-days-a-week. The 1981 "Industry (Transfer of Departmental Administration and Ministerial Functions) Order" transferred responsibility for Irish Steel from the Minister for Industry and Commerce to the Minister for Energy.
In 1972, Edward A. Coleman (the general manager of Irish Steel and a member of a delegation from the Confederation of Irish Industry travelling for discussions with EEC officials in Brussels), was among those killed in the Staines air disaster.
A fall in steel prices in Europe during the 1980s led to layoffs at Irish Steel, and the work-force was progressively reduced from 650. The assets of the company were sold to Irish Ispat (a subsidiary of Ispat International), for IR£1, in 1996. Under the terms of the sale agreement, the Haulbowline plant was operated under the condition that "£30 million would be invested in the plant and its 330 jobs would be secured" for at least five years. Shortly after this term ended in 2001, the plant was closed and 450 jobs were lost.
Controversy
Safety
According to a 2005 article in The Irish Times, "Irish Ispat's tenure at Haulbowline was marked by controversy, with the firm failing to invest" as expected under the negotiated takeover agreement. There were several worker deaths between 1999 and 2001, including that of a lab technician who died in a fire. According to an inquest hearing, the plant's administrative block had no sprinklers, fire escapes or fire alarms, and that the "company's fire engine failed to start because of a flat battery". According to other reports, the plant's safety manager had been refused budget for improved fire-safety training.
Closure
The plant was closed, with limited notice, by Ispat International in 2001. At the time of closure, the company had debts of more than €57m. Reports of land and asset sales, prior to closure, led to some accusations of "asset-stripping" by the parent company. One such asset disposal, in the months prior to closure, involved the sale of a 30-acre site (for an undisclosed sum) to build a hazardous waste incinerator to the "fury of local residents". As of 2002, creditors were still owed over €20m, including over €7m due to former-workers for statutory redundancy and other payments.
Environmental impact
From at least the 1960s, waste materials (including toxic chemicals and steel slag) used in the steel production process were dumped by Irish Steel on the eastern part of Haulbowline island. This dumping site became known as the "East Tip", and was described in later reports as one of Ireland's "worst polluted former industrial sites".
The "East Tip" expanded over several decades to include 650,000 cubic metres of waste, extending eastwards from Haulbowline's naval dockyard. The processing waste acted as approximately of land reclamation infill, and the dumped materials reputedly increased Haulbowline island from approximately to over in size. According to the terms of planning permission, received by Irish Steel in 1981, there were no controls placed on the material that could be dumped or on protections required to prevent leachate into the harbour. By the time of the plant's closure in 2001, radioactive and Chromium 6 contamination was found to have remained in the island's soil. Campaigners, including Erin Brockovich, requested government action on the contamination issue.
As of 2011, it was reported that the contamination at the site had cost the state "more than €50 million — mostly in legal costs". As of 2014, €52 million had been spent on clearing the site, with "a further €40 million [earmarked] to make the site safe". While the Environmental Protection Agency had attributed €15.9m of the projected site cleanup costs to Irish Ispat (formerly Irish Steel), the High Court dismissed a claim by the state to have the company's liquidator cover the cost of making the site environmentally safe. The Irish government was later threatened with legal action by the European Commission, for a failure to meet its obligations under the Waste Framework Directive. In 2016, it was reported that the remediation works budget, of €61m, would not be sufficient to complete the full cleanup and redevelopment project.
The cleanup and redevelopment of the former Irish Steel "East Tip" site took more than a decade to complete, between 2011 (when the work necessary to prepare a waste licence application was discussed) and 2021 (when the site was opened as a park). Haulbowline Island Amenity Park was officially opened in January 2021.
References
Former state-sponsored bodies of the Republic of Ireland
Iron and steel mills
Defunct manufacturing companies of the Republic of Ireland | Irish Steel | [
"Chemistry"
] | 1,324 | [
"Iron and steel mills",
"Metallurgical facilities"
] |
67,842,698 | https://en.wikipedia.org/wiki/Kotan%20%28village%29 | A kotan (Katakana: コタン) is a traditional settlement of the Ainu people.
Introduction
Due to the scarcity of primary source materials (as the Ainu did not have a system of writing), all studies on the Ainu kotan (based on Russian, Japanese, and English works) will have different analyzations and opinions, varying largely depending on the researchers and the duration of their work.
The word kotan is often erroneously translated to as a "village"; the term generally applies to all human settlements, regardless of their size. For example, in the Ainu translation of the Bible, Rome and Jerusalem are referred to as yerusalem kotan and roma kotan, respectively.
Description
Unlike other hunter gatherers, who did not settle in one place at any given time, the Ainu were highly dependent on fishing, therefore they settled by places that had good fishing (like river estuaries) and built settlements there, though depending on the season the Ainu would move to a new fishing spot. For example, if the salmon spawning grounds differed along the same stretch of river, the Ainu would migrate along with the ground, leading to kotans being built at intervals of about 5 to 7 kilometers.
Average kotans were rather small and not very populous. A kotan can be made up of around five to seven houses, though there were larger settlements of ten or more. More than 20 households generally was the result of the forced Ainu labor mobilization under the place-contract system (場所請負制) established by the Matsumae clan during the Edo period, which cannot be called a traditional-style kotan anymore. In 1856, Takeshirō Matsuura (an explorer in Hokkaido) reported the statistical kotan was inhabited by 10 families and 47 people in total.
A kotan generally consisted of cise (thatched-roof houses), hepereset (cages for keeping young bears usually for the iomante ceremony), an ashinru and/or menokol (lavatories for the males and females respectively), a pui (stilt warehouse for storing food), and various drying racks for wild plants, fish, and animal skins. There is usually an nusasan (altar) dedicated to the Inau god as well. In later years, chashis (Ainu fortifications) can be found around Ainu settlements.
There was a common ground near the kotans called the iwolo, where kotan residents were free to cut down trees, hunt, fish, and forage for wild plants and cultivate them. Adjacent kotans were invited to share the hunting grounds, conduct the iomante ceremony together, and most often having one chief for several kotan. Such a collection of friendly kotan are called ekasi itokpa.
Current Ainu kotan
There is only one Ainu kotan still continually inhabited to the present day, the Lake Akan kotan in Kushiro. In 1959, there were still a scattering of Ainu kotans around Lake Akan, before Mitsuko Maeda of the Maeda Ippoen Foundation (an organization that helped in conserving Lake Akan) suggested the remaining Ainu to relocate to the new land purchased by him. As the Ainu relocated to the new land free of charge, the Lake Akan kotan was created.
Use of kotan as a place name
Each kotan had a unique place name, and as such, the suffix kotan can be found throughout Hokkaido, Sakhalin, and the Kuril islands.
Hokkaido
Shakotan (積丹, "summer village")
Kotanbetsu (古丹別, "village river")
Kamuikotan (神居古丹, "village of the gods")
Tokotan (床丹, "destroyed village")
Shikotan (色丹, "real village")
Ayumikotan (歩古丹, "abalone village")
Okotanpe (オコタンペ, "river with a village downstream")
Kotani (小谷, "village river")
Shimakotan (島古丹, "village with many stones")
Sakhalin
Kushunkotan (久春古丹)
Kuril Islands
Onnekotan (温禰古丹, "large village")
Shashikotan (捨子古丹, "kombu village")
Chirinkotan (知林古丹, "mudslide village")
Kharimkotan (春牟古丹, "village of many cardiocrinum")
References
Ainu
Ainu culture
Architecture in Japan
Vernacular architecture
Indigenous architecture
Construction | Kotan (village) | [
"Engineering"
] | 966 | [
"Construction"
] |
67,842,736 | https://en.wikipedia.org/wiki/Conducting%20redox%20polymer | Conducting redox polymers (CRPs) or intrinsically conducting redox polymers are organic polymers that combine the properties of conducting polymers and redox active polymers. They consist of a conducting polymer backbone with redox active pendant groups.
The conducting backbone is usually polythiophene or polypyrrole based. As pendant groups quinones, radicals (eg. TEMPO), and metal complexes (eg. ferrocene) have been used.
The conducting polymer backbone makes the addition of conductive additives obsolete which is a major advantage for practical applications like energy storage compared to conventional redox active polymers.
Synthesis
The general strategy for the synthesis of conducting redox polymers is to attach a redox active group to a monomer (or a trimer) of the respective conducting polymer. These monomers, which are often EDOT derivatives, are subsequently polymerised either by electropolymerization or by chemical oxidative polymerisation (eg. with FeCl3 or Fe(OTs)3).
Redox Potential Matching
When designing a conducting redox polymer it is important to consider the different redox-potentials of the pendant group and the polymer backbone, as the polymer backbone is only conductive in its doped state. If the polymer backbone loses its conductivity before the redox reaction of the pendant group is complete, the pendant group can get trapped in its charged state. In order to avoid charge trapping, the polymer backbone must be sufficiently conductive in the potential region in which the redox-reaction of the pendant group occurs, hence the doping onset potential has to be lower than the redox-potential of the oxidation, or higher than the redox-potential of the reduction. Conducting redox polymers in which this is fulfilled, are referred to as having a potential match between the polymer backbone and the pendant group.
References
Polymers | Conducting redox polymer | [
"Chemistry",
"Materials_science"
] | 377 | [
"Polymers",
"Polymer chemistry"
] |
67,843,590 | https://en.wikipedia.org/wiki/Bromoxynil%20octanoate | Bromoxynil octanoate is a herbicide active ingredient, closely related to bromoxynil, ioxynil, and ioxynil octanoate. Bromoxynil controls broad leafed weeds in many crops, and is used in the USA, Europe and Australia, on crops, roadsides and turf.
It has been sold under the trademarks Bromoxynil, Broclean, Bromox, Brominex, Bromolex, Bromolex and Bromoxymobeed.
Bromoxynil octanoate in the environment has a half-life of about 10 days, and breaks down into harmless compounds.
Bromoxynil octanoate acts by inhibiting photosynthesis at photosystem II, destroying cells, giving it a Group C (numeric: Group 6) HRAC. Weeds show symptoms after four to seven days of chlorotic leaves and desiccation.
References
Herbicides
Bromobenzene derivatives
Nitriles
Phenol esters
Octanoate esters | Bromoxynil octanoate | [
"Chemistry",
"Biology"
] | 223 | [
"Herbicides",
"Nitriles",
"Biocides",
"Functional groups"
] |
67,844,064 | https://en.wikipedia.org/wiki/Lia%20radiological%20accident | The Lia radiological accident began on December 2, 2001, with the discovery of two orphan radiation sources near the Enguri Dam in Tsalenjikha District in the country of Georgia. Three villagers from Lia were unknowingly exposed. All three men were injured, one of whom eventually died. The accident was a result of unlabeled radioisotope thermoelectric generator (RTG) cores which had been improperly dismantled and left behind from the Soviet era. The International Atomic Energy Agency (IAEA) led recovery operations and organized medical care.
Source of the radioactive material
In the early 1980s, a series of radio relays were built to connect the Enguri Dam with the Hudoni Dam, which was under construction. The relays were in remote territory with no reliable access to electricity, and thus were powered with a series of eight radioisotope thermoelectric generators (RTGs) manufactured in 1983. Each RTG was a Beta-M type powered by strontium-90, and contained some 12951480 TBq of radioactivity. However, the Hudoni dam's construction was stopped as Georgian independence from the Soviet Union drew near. The stations and their RTGs were abandoned and eventually dismantled. The RTGs became lost at this time. Two were rediscovered in 1998, leading to no injuries. Two more were found in 1999, and again led to no injuries or significant radiation exposure. Two more were rediscovered in 2001, which led to the accident. The other two sources remain unaccounted for. The sources were not marked, and had been removed from the rest of the generator housing. They were heavy for their size, weighing despite being only . Upon their recovery, it was determined the radiation emitted at the surface of the sources was 4.6 Sieverts (Sv) per hour. A fully absorbed whole-body dose of 5 Sv has a 50% chance of death. The original dose output at the time of their construction would have been much higher, but said output had decreased 40% since their construction due to radioactive decay. The actual dose received per hour would be lower unless physically touching the source, as radiation decreases with distance according to the inverse-square law.
Accident
Three men from Lia (later designated as patients 1-DN, 2-MG, and 3-MB by the IAEA) had driven to a forest overlooking the Enguri Dam reservoir to gather firewood. They drove up a nearly impassable road in snowy winter weather, and discovered two canisters at around 6 pm. Around the canisters there was no snow for about a radius, and the ground was steaming. Patient 3-MB picked up one of the canisters and immediately dropped it, as it was very hot. Deciding that it was too late to drive back, and realizing the apparent utility of the devices as heat sources, the men decided to move the sources a short distance and make camp around them. Patient 3-MB used a stout wire to pick up one source and carried it to a rocky outcrop that would provide shelter. The other patients lit a fire, and then patients 3-MB and 2-MG worked together to move the other source under the outcrop. They ate dinner and had a small amount of vodka, while remaining close to the sources. Despite the small amount of alcohol, they all vomited soon after consuming it, the first sign of acute radiation syndrome (ARS), about three hours after first exposure. Vomiting was severe and lasted through the night, leading to little sleep. The men used the sources to keep them warm through the night, positioning them against their backs, and as close as . The next day, the sources may have been hung from the backs of Patient 1-DN and 2-MG as they loaded wood onto their truck. They felt very exhausted in the morning and only loaded half the wood they intended. They returned home that evening.
Aftermath
Medical
Two days after exposure, on December 4, patient 2-MG visited a local doctor but did not mention the mysterious heating source, and the doctor assumed he was drunk. The resulting treatment, however, did clear up the symptoms. On December 15, patients 1-DN and 2-MG developed burning and itching on the small of their backs, where the radiation source had been closest. Patient 1-DN lost his voice as well but did not seek care at that time. The wife of patient 3-MB and the brother of patient 2-MG learned that all three men were ill with similar symptoms, including increasing desquamation, especially on their backs. The wife and brother reached out to the police, who suggested that all three men seek medical attention. All three patients were finally hospitalized on December 22, and it was determined they had ARS. Patient 3-MB was released on January 23, 2002, as his injury was mild. The other patients remained in serious condition, and the Government of Georgia petitioned the IAEA for help treating them. The IAEA intervened: patient 1-DN was sent to Burnasyan Federal Medical Biophysical Center in Moscow, and Patient 2-MG was sent to the Percy military hospital in Paris. Patient 2-MG was hospitalized for over a year, and required extensive skin grafts, but survived and was discharged on March 18, 2003. Patient 1-DN's injuries lingered. He had received the greatest exposure on his back, as well as damage to his heart and vital organs. A large radiation ulcer formed on much of his upper left back. Despite intensive care, repeated antibiotics, multiple surgeries, and an attempted skin graft, the wound did not heal. His condition was complicated by tuberculosis, which prevented effective treatment of lung injury. He developed sepsis, and died of heart failure on May 13, 2004, 893 days after first exposure.
Doses
Radiation doses were estimated in several different ways, but it was clear that Patient 2-MG received the greatest dose. Below, doses are measured in grays. A whole-body dose of 10 Gy is 99% fatal, a dose of 6 Gy is 50% fatal with treatment, and a dose of 2 Gy is 5% fatal with treatment. Localized doses, especially where the patients suffered radiation ulcers, may have been much higher. Patient 1-DN, despite a survivable whole-body dose of between 2.8 and 5.4 Gy, received 21-37 Gy to his shoulder, which eventually killed him. In the chart below, there is some uncertainty in the measurements. The calibration curve method is from an assumed exposure time, distance, and rate. This is close to the doses determined by the measurements of chromosome aberrations taken from blood samples analyzed by the Georgia Cytogenetics Laboratory. Also included are doses calculated by the Dolphin method, which uses a slightly different detector. No other people in the area were found to have been exposed.
Source recovery
The day after the hospitalization, Georgian authorities attempted to find the suspected radiation sources, but bad weather prevented them from reaching the site. On December 29 they tried again and ascertained the exact location, also shooting video footage. On January 4, 2002, the Georgian government appealed to the IAEA for help. A first attempt at recovering the sources was made two days later, but failed again due to weather. A fact-finding mission was led to determine how to best recover the sources, and their nature. The containers were extremely well built, which prevented the loss of radioactive material under all but the most extreme conditions. They had survived being abandoned in the woods for over a decade and had released no radioactive material. The radiation hazard was localized only, due to escaping ionizing radiation. For this reason, the IAEA had intended to wait until the spring thaw to recover the sources, but concerns by residents led the Georgian government to push for an early recovery. A tactically difficult recovery mission was successfully carried out on February 23, 2002.
The recovery mission faced numerous challenges, with winter weather being chief among them. The village of Potskho Etseri was used as the base of operations. A special container lined with of lead and weighing was built for the purpose. An old military truck was converted for hauling the container. Special handling tools were created to manipulate the source and put it in a container. A group of 41 people were organized to take turns handling the source, with each person spending not more than 40 seconds near it. In the end, only 24 people were needed to actually be near the sources, and only those 24 people received significant doses. Worker radiation doses were monitored, and the highest dose was not more than 1.16 mSv, less than 10% of the dose of a full-body CT scan. The sources were successfully recovered, and carefully escorted by police back to a permanent storage location. Doses received between placing the sources in the truck and closing the lid over them was higher than expected due to the presence of a tarp over the truck. Inclement weather had prevented its removal, and it acted to reflect and scatter radiation back at the workers. The IAEA also noted that better tool design, as well as the use of more workers at a time to provide spotting capabilities, would have made the process faster and safer. Overall, the IAEA considered the recovery a success with no major safety issues.
Analysis
The IAEA's final report concluded that the proximate cause of the accident was that the sources were unmarked and unlabeled, and thus their danger could not be known. It also chastised the illegal abandonment of the sources to begin with. The report stressed the importance of basic knowledge of radiation injuries by clinicians and called for increased programs to make them aware of the signs of radiation overexposure. The initial clinician who treated patient 2-MG did not accurately assess the injury (partly due to 2-MG's failure to mention the orphan source), thus delaying proper treatment for almost three weeks.
Between the fall of the Soviet Union in 1991 and 2006, the IAEA had recovered some 300 orphan sources in Georgia, many lost from former industrial and military sites abandoned in the economic collapse after the Soviet breakup.
References
External links
Video of the recovery
Full IAEA report on the incident
2001 health disasters
2001 in Georgia (country)
Civilian nuclear power accidents
December 2001 events in Europe
Radiation accidents and incidents
Samegrelo-Zemo Svaneti
Strontium
Waste disposal incidents
2001 disasters in Georgia (country) | Lia radiological accident | [
"Technology"
] | 2,149 | [
"Environmental impact of nuclear power",
"Civilian nuclear power accidents"
] |
67,844,712 | https://en.wikipedia.org/wiki/Simeon%20Chituru%20Achinewhu | Simeon Chituru Achinewhu (born 15 August, 1946) is a Nigerian food and nutrition biochemist, scholar and university administrator who served as the past president-general of Ogbakor Ikwerre Socio-cultural Organisation Worldwide. He was vice–chancellor of River State University (formerly Rivers State University of Science and Technology), from October 2000 until May 2007. In 2005 he was named the most research active vice-chancellor in the Nigerian university system.
Background and education
Born on 15 August 1946 in Ikwerre Local Government Area, Rivers State, Nigeria, Achinewhu had his primary education in his home town Aluu. He finished from County Grammar School, Ikwerre/Etche in 1963 with Grade One. He later proceeded to Government Secondary School, Owerri and got his Higher School Certificate in physics, chemistry, and zoology in 1965. In 1970, Achinewhu graduated from the University of Ibadan, B.Sc. second class honors, M.Sc. in 1972 and Ph.D. 1975 in food science and technology from University of Reading, UK.
Career
Starting as lecturer at Rivers State University in food chemistry/biochemistry, food process technology, safety and fermentation, toxicology and nutrition in 1975, he has remained there to-date. He is also a researcher in Rivers State University, Port Harcourt (formerly Rivers State University of Science and Technology) and research is mostly centered on the composition and quality evaluation of Nigerian local foodstuff.
As of 2021, Achinewhu serves as professor emeritus at the Rivers State University.
Prior to being appointed vice-chancellor of Rivers State University 2000, Achinewhu held the following positions:
Dean, Post Graduate School (1998-2000)
Head of the Department of Food Science & Technology (November 1995 – June 1998)
Dean, Faculty of Agriculture (1989-1994)
Director, Rivers Institute of Agricultural Research & Training (RIART), Rivers State University (1986-1989)
Awards and visits
In course of his research and scholastic endeavors, Achinewhu has visited many universities and has received a number of international as well as local awards.
International academic awards
Post-doctorate fellowship senior scholar Fulbright Fellowship (1985), where he was a visiting Fulbright fellow.
Post-doctorate fellow Association of Commonwealth Universities (1984-1985), where he was a visiting Commonwealth fellow
International academic visits
Post doctorate visit on a senior scholar Fulbright fellowship University of Massachusetts (September – December 1985)
Post doctorate visit on Association of Commonwealth Universities Fellowship University of Leeds, UK (October 1984 – July 1985)
Visiting post-doctorate fellow at the University of Reading, UK (1980)
In 2010 he was selected and worked as an expert in Europe-Africa Quality Connect: A collaborative project in five African universities between European Universities Association (EUA) and the Association of African Universities (AAU), sponsored by European Commission.
Academic contributions
Achinewhu has analyzed more than fifty homegrown foodstuffs, which include seeds, nuts, tubers, spices, and herbs. These indigenous food items where examined and explored for their nutrient compositions and quality of protein content. Details of his findings are being used along with others in the compendium of Nigeria's food composition table.
He evolved the processing and production of coffee from coffee seed grown in Bayelsa State, Nigeria.
He did research on cassava processing, which identified upgrade cassava cultivars with superior quality food values with regards to product output and other physico-chemical properties. He identified new cultivars with high starch yield and therefore high export potentials.
He developed a baby food (weaning) supplement employing the use of a combination of fermented plant food products. This was used to nourish children who were undernourished, in the days of Better Life Programme for Rural Women.
Personal life
Achinewhu married Eunice Achinewhu (nee Eunice Nyema Otto) in 1972 and they have four children.
He is a reverend canon of the Church of Nigeria Anglican Communion. He is a crown of peace, justice of peace, and the national president of Peace Builders Association (Council of Ambassadors for Peace and Unification)
References
1946 births
Living people
Nigerian biochemists
University of Ibadan alumni
Alumni of the University of Reading
Ikwerre people
Academic staff of Rivers State University
Biochemistry educators
Agriculture educators | Simeon Chituru Achinewhu | [
"Chemistry",
"Biology"
] | 885 | [
"Biochemistry",
"Biochemistry educators"
] |
67,844,736 | https://en.wikipedia.org/wiki/Sarah%20Tolbert | Sarah Helen Tolbert is an American chemist who is a professor in the department of chemistry and biochemistry at the University of California, Los Angeles. Her research considers self-assembled nanomaterials, which includes inorganic phases and colloidal materials.
Early life and education
Tolbert's father, Bert Tolbert, was a professor of chemistry at the University of Colorado Boulder. She was one of four daughters. Tolbert was an undergraduate student at Yale University. She moved to the University of California, Berkeley for graduate studies, where she studied the structural, optical and cooperative properties of nanomaterials. She was a postdoctoral scholar at the University of California, Santa Barbara.
Research and career
Tolbert is interested in the nanoscale assembly of materials, and how these nanostructures give rise to novel phenomena. In particular, Tolbert has investigated arrays of colloids. Colloids assemble into closely-packed areas that can be used to create large scale periodic photonics materials.
Tolbert is interested in inorganic/organic co-assembly. To this end she combines block co-polymers or organic surfactants with short-chain inorganic oligomers. Her early work involved the development of novel conjugated polymer morphologies for efficient light-emitting diodes. Amongst these morphologies, Tolbert showed it was possible to embed polymers in a silica host matrix, where stretching the matrix results in aligned polymer chains that emit linearly polarized light.
Tolbert works on self-assembled nanomaterials. She is particularly interested in introducing structure and periodicity to composite materials. Tolbert has studied phase transitions in inorganic solids. She has created novel, nanostructured electrodes to allow the fast charging of batteries. These include molybdenum disulphide nanocrystal composites, where internal atomic-scale pathways allow lithium ions to speedily move through the electrode. The nanostructure electrodes not only support the efficient charging of batteries but also stable charge and discharging cycles.
Tolbert is a developer for Battery Streak, a spin-out company who look to reduce that charging time of electronic devices.
Awards and honors
Alfred P. Sloan Fellowship (2001)
National Science Foundation CAREER Award (2000)
Beckman Young Investigators Award (2000)
Office of Naval Research Young Investigator Award (1999)
Selected publications
Personal life
Tolbert's three sisters are all academics, including atmospheric chemist Margaret Tolbert, political scientist Caroline Tolbert and ethnomusicologist Elizabeth Tolbert. She was one of four daughters. Tolbert met her husband, Benjamin Schwartz, whilst a graduate student at the University of California, Berkeley.
References
Living people
Year of birth missing (living people)
University of California, Los Angeles faculty
Yale University alumni
UC Berkeley College of Chemistry alumni
American women chemists
American inorganic chemists
American materials scientists
Women materials scientists and engineers
21st-century American women | Sarah Tolbert | [
"Chemistry",
"Materials_science",
"Technology"
] | 591 | [
"Inorganic chemists",
"Materials scientists and engineers",
"American inorganic chemists",
"Women materials scientists and engineers",
"Women in science and technology"
] |
67,845,153 | https://en.wikipedia.org/wiki/Protist%20locomotion | Protists are the eukaryotes that cannot be classified as plants, fungi or animals. They are mostly unicellular and microscopic. Many unicellular protists, particularly protozoans, are motile and can generate movement using flagella, cilia or pseudopods. Cells which use flagella for movement are usually referred to as flagellates, cells which use cilia are usually referred to as ciliates, and cells which use pseudopods are usually referred to as amoeba or amoeboids. Other protists are not motile, and consequently have no built-in movement mechanism.
Overview
Unicellular protists comprise a vast, diverse group of organisms that covers virtually all environments and habitats, displaying a menagerie of shapes and forms. Hundreds of species of the ciliate genus Paramecium or flagellated Euglena are found in marine, brackish, and freshwater reservoirs; the green algae Chlamydomonas is distributed in soil and fresh water world-wide; parasites from the genus Giardia colonize intestines of several vertebrate species. One of the shared features of these organisms is their motility, crucial for nutrient acquisition and avoidance of danger. In the process of evolution, single-celled organisms have developed in a variety of directions, and thus their rich morphology results in a large spectrum of swimming modes.
Many swimming protists actuate tail-like appendages called flagella or cilia in order to generate the required thrust. This is achieved by actively generating deformations along the flagellum, giving rise to a complex waveform. The flagellar axoneme itself is a bundle of nine pairs of microtubule doublets surrounding two central microtubules, termed the 9+2 axoneme, and cross-linking dynein motors, powered by ATP hydrolysis, perform mechanical work by promoting the relative sliding of filaments, resulting in bending deformations.
Although protist flagella have a diversity of forms and functions, two large families, flagellates and ciliates, can be distinguished by the shape and beating pattern of their flagella.
In the phylogenetic tree on the right, aquatic organisms (living in marine, brackish, or freshwater environments) have their branches drawn in blue while parasitic organisms have their branches drawn in red. Ciliates are indicated by an asterisk after their names. For each phylum marked in bold font, a representative organism has been sketched next to its name.
Modes of locomotion
Flagellates
Flagella are used in prokaryotes (archaea and bacteria) as well as protists. In addition, both flagella and cilia are widely used in eukaryotic cells (plant and animal) apart from protists.
The regular beat patterns of eukaryotic cilia and flagella generates motion on a cellular level. Examples range from the propulsion of single cells such as the swimming of spermatozoa to the transport of fluid along a stationary layer of cells such as in a respiratory tract. Though eukaryotic flagella and motile cilia are ultrastructurally identical, the beating pattern of the two organelles can be different. In the case of flagella, the motion is often planar and wave-like, whereas the motile cilia often perform a more complicated three-dimensional motion with a power and recovery stroke.
Eukaryotic flagella—those of animal, plant, and protist cells—are complex cellular projections that lash back and forth. Eukaryotic flagella are classed along with eukaryotic motile cilia as undulipodia to emphasize their distinctive wavy appendage role in cellular function or motility. Primary cilia are immotile, and are not undulipodia.
Flagellates typically have a small number of long flagella distributed along the bodies, and they actuate them to generate thrust. The set of observed movement sequences includes planar undulatory waves and traveling helical waves, either from the base to the tip, or in the opposite direction. Flagella attached to the same body might follow different beating patterns, leading to a complex locomotion strategy that often relies also on the resistance the cell body poses to the fluid.
Ciliates
In contrast to flagellates, propulsion of ciliates derives from the motion of a layer of densely-packed and collectively-moving cilia, which are short hair-like flagella covering their bodies. The seminal review paper of Brennen and Winet (1977) lists a few examples from both groups, highlighting their shape, beat form, geometric characteristics and swimming properties. Cilia may also be used for transport of the surrounding fluid, and their cooperativity can lead to directed flow generation. In higher organisms this can be crucial for internal transport processes, as in cytoplasmic streaming within plant cells, or the transport of ova from the ovary to the uterus in female mammals.
Ciliates generally have hundreds to thousands of cilia that are densely packed together in arrays. Like the flagella, the cilia are powered by specialised molecular motors. An efficient forward stroke is made with a stiffened flagellum, followed by an inefficient backward stroke made with a relaxed flagellum. During movement, an individual cilium deforms as it uses the high-friction power strokes and the low-friction recovery strokes. Since there are multiple cilia packed together on an individual organism, they display collective behaviour in a metachronal rhythm. This means the deformation of one cilium is in phase with the deformation of its neighbor, causing deformation waves that propagate along the surface of the organism. These propagating waves of cilia are what allow the organism to use the cilia in a coordinated manner to move. A typical example of a ciliated microorganism is the Paramecium, a one-celled, ciliated protozoan covered by thousands of cilia. The cilia beating together allow the Paramecium to propel through the water at speeds of 500 micrometers per second.
Amoebas
The third prevalent forms of protist cell motility is actin-dependent cell migration. The evolution of flagellar-based swimming has been well studied, and strong evidence suggests a single evolutionary origin for the eukaryotic flagellum occurred before the diversification of modern eukaryotes. On the other hand, actin-dependent crawling uses many different molecular mechanisms, and the study of how these evolved is only just beginning.
Colonial protists
Gonium is a genus of colonial algae belonging to the family Volvocaceae. Typical colonies have 4 to 16 cells, all the same size, arranged in a flat plate, with no anterior-posterior differentiation. In a colony of 16 cells, four are in the center, and the other 12 are on the four sides, three each.
Since the work of August Weismann on germ-plasm theory in biology and of Julian Huxley on the nature of the individual in evolutionary theory, the various species of green algae belonging to the family Volvocaceae have been recognized as important ones in the study of evolutionary transitions from uni- to multicellular life. In a modern biological view, this significance arises from a number of specific features of these algae, including the fact that they are an extant family (obviating the need to study microfossils), are readily obtainable in nature, have been studied from a variety of perspectives (biochemical, developmental, genetic), and have had significant ecological studies. From a fluid dynamical perspective, their relatively large size and easy culturing conditions allow for precise studies of their motility, the flows they create with their flagella, and interactions between organisms, while their high degree of symmetry simplifies theoretical descriptions of those same phenomena.
As they are photosynthetic, the ability of these algae to execute phototaxis is central to their life. Because the lineage spans from unicellular to large colonial forms, it can be used to study the evolution of multicellular coordination of motility. Motility and phototaxis of motile green algae have been the subjects of an extensive literature in recent years, focusing primarily on the two extreme cases: unicellular Chlamydomonas and much larger Volvox, with species composed of 1000–50,000 cells. Chlamydomonas swims typically by actuation of its two flagella in a breast stroke, combining propulsion and slow body rotation. It possesses an eyespot, a small area highly sensitive to light, which triggers the two flagella differently. Those responses are adaptive, on a timescale matched to the rotational period of the cell body, and allow cells to scan the environment and swim toward light. Multicellular Volvox shows a higher level of complexity, with differentiation between interior germ cells and somatic cells dedicated to propulsion. Despite lacking a central nervous system to coordinate its cells, Volvox exhibits accurate phototaxis. This is also achieved by an adaptive response to changing light levels, with a response time tuned to the colony rotation period which creates a differential response between the light and dark sides of the spheroid.
In light of the above, a natural questions is as follows: How does the simplest differentiated organism achieve phototaxis? In the Volvocine lineage the species of interest is Gonium. This 8- or 16-cell colony represents one of the first steps to true multicellularity, presumed to have evolved from the unicellular common ancestor earlier than other Volvocine algae. It is also the first to show cell differentiation.
The 16-cell Gonium colony shown in the diagram on the right is organized into two concentric squares of respectively 4 and 12 cells, each biflagellated, held together by an extracellular matrix. All flagella point out on the same side: It exhibits a much lower symmetry than Volvox, lacking anterior-posterior symmetry. Yet it performs similar functions to its unicellular and large colonies counterparts as it mixes propulsion and body rotation and swims efficiently toward light. The flagellar organization of inner and peripheral cells deeply differs: Central cells are similar to Chlamydomonas, with the two flagella beating in an opposing breast stroke, and contribute mostly to the forward propulsion of the colony. Cells at the periphery, however, have flagella beating in parallel, in a fashion close to Volvox cells. This minimizes steric interactions and avoids flagella crossing each other. Moreover, these flagella are implanted with a slight angle and organized in a pinwheel fashion [see Fig. 1(b)]: Their beating induces a left-handed rotation of the colony, highlighted in Figs. 1(c) and 1(d) and in Supplemental Movie 1 [29]. Therefore, the flagella structure of Gonium reinforces its key position as intermediate in the evolution toward multicellularity and cell differentiation.
These small flat assemblies show intriguing swimming along helical trajectories—with their body plane almost normal to the swimming direction—that have attracted the attention of naturalists since the 18th century. Yet the way in which Gonium colonies bias their swimming toward the light remains unclear. Early microscopic observations have identified differential flagellar activity between the illuminated and the shaded sides of the colony as the source of phototactic reorientation. Yet a full fluid-dynamics description, quantitatively linking the flagellar response to light variations and the hydrodynamic forces and torques acting on the colony, is still lacking. From an evolutionary perspective, phototaxis in Gonium raises fundamental issues such as the extent to which the phototactic strategy of the unicellular ancestor is retained in the colonial form, how the phototactic flagella reaction adapted to the geometry and symmetry of the colony, and how it leads to effective reorientation.
Protist taxis: Directed motion
Phototaxis
Some protists can move toward or away from a stimulus, a movement referred to as taxis. For example, movement toward light, termed phototaxis, is accomplished by coupling their locomotion strategy with a light-sensing organ. Eukaryotes evolved for the first time in the history of life the ability to follow light direction in three dimensions in open water. The strategy of eukaryotic sensory integration, sensory processing and the speed and mechanics of tactic responses is fundamentally different from that found in prokaryotes.
Both single-celled and multi-cellular eukaryotic phototactic organisms have a fixed shape, are polarized, swim in a spiral and use cilia for swimming and phototactic steering. Signalling can happen via direct light-triggered ion currents, adenylyl cyclases or trimeric G-proteins. The photoreceptors used can also be very different (see below). However, signalling in all cases eventually modifies the beating activity of cilia. The mechanics of phototactic orientation is analogous in all eukaryotes. A photosensor with a restricted view angle rotates to scan the space and signals periodically to the cilia to alter their beating, which will change the direction of the helical swimming trajectory. Three-dimensional phototaxis can be found in five out of the six eukaryotic major groups (opisthokonts, Amoebozoa, plants, chromalveolates, excavates, rhizaria).
Pelagic phototaxis is present in green algae – it is not present in glaucophyte algae or red algae. Green algae have a "stigma" located in the outermost portion of the chloroplast, directly underneath the two chloroplast membranes. The stigma is made of tens to several hundreds of lipid globules, which often form hexagonal arrays and can be arranged in one or more rows. The lipid globules contain a complex mixture of carotenoid pigments, which provide the screening function and the orange-red colour, as well as proteins that stabilize the globules. The stigma is located laterally, in a fixed plane relative to the cilia, but not directly adjacent to the basal bodies. The fixed position is ensured by the attachment of the chloroplast to one of the ciliary roots. The pigmented stigma is not to be confused with the photoreceptor. The stigma only provides directional shading for the adjacent membrane-inserted photoreceptors (the term "eyespot" is therefore misleading). Stigmata can also reflect and focus light like a concave mirror, thereby enhancing sensitivity.
In the best-studied green alga, Chlamydomonas reinhardtii, phototaxis is mediated by a rhodopsin pigment, as first demonstrated by the restoration of normal photobehaviour in a blind mutant by analogues of the retinal chromophore. Two archaebacterial-type rhodopsins, channelrhodopsin-1 and -2, were identified as phototaxis receptors in Chlamydomonas. Both proteins have an N-terminal 7-transmembrane portion, similar to archaebacterial rhodopsins, followed by an approximately 400 residue C-terminal membrane-associated portion. CSRA and CSRB act as light-gated cation channels and trigger depolarizing photocurrents. CSRA was shown to localize to the stigma region using immunofluorescence analysis (Suzuki et al. 2003). Individual RNAi depletion of both CSRA and CSRB modified the light-induced currents and revealed that CSRA mediates a fast, high-saturating current while CSRB a slow, low-saturating one. Both currents are able to trigger photophobic responses and can have a role in phototaxis, although the exact contribution of the two receptors is not yet clear.
As in all bikonts (plants, chromalveolates, excavates, rhizaria), green algae have two cilia, which are not identical. The anterior cilium is always younger than the posterior one. In every cell cycle, one daughter cell receives the anterior cilium and transforms it into a posterior one. The other daughter inherits the posterior, mature cilium. Both daughters then grow a new anterior cilium.
As all other ciliary swimmers, green algae always swim in a spiral. The handedness of the spiral is robust and is guaranteed by the chirality of the cilia. The two cilia of green algae have different beat patterns and functions. In Chlamydomonas, the phototransduction cascade alters the stroke pattern and beating speed of the two cilia differentially in a complex pattern. This results in the reorientation of the helical swimming trajectory as long as the helical swimming axis is not aligned with the light vector.
Thermotaxis
Temperature is a key environmental factor for living organisms because chemical reaction rates and physical characteristics of biological materials can change substantially with temperature. Living organisms acclimate to cold and heat stress using acquired mechanisms, including the ability to migrate to an environment with temperatures suitable for inhabitation. One of the simplest forms of the behavior to migrate to a suitable thermal environment is thermotaxis. Thermotaxis has been found in multicellular organisms, such as Caenorhabditis elegans and Drosophila melanogaster, as well as in unicellular organisms, such as Paramecium caudatum, Dictyostelium discoideum, Physarum polycephalum, and Escherichia coli. Individual cells within multicellular organisms also show thermotaxis. For example, mammalian sperm migrate through the oviduct to the fertilization site guided by a rise in temperature.
The investigation of how unicellular organisms migrate toward preferred temperatures began more than 100 years ago. In particular, the thermotactic behavior of Paramecium cells has been well studied. Paramecium cells accumulate at sites that are close to the cultivation temperature, i. e. the temperature at which cells are grown. Accumulation at these sites occurs because cells frequently reverse their swimming direction when they encounter a temperature change that deviates from the cultivation temperature and increase their swimming velocity when they experience a temperature change that approaches the cultivation temperature. The reversal in swimming direction is induced by a depolarizing receptor potential, which triggers an action potential in the cilia. These studies on Paramecium cells highlighted the thermotaxis in unicellular organisms more than 30 years ago, but the molecular mechanisms for thermoreception and signal transduction are not yet understood.
The understanding of the molecular mechanisms for thermotaxis has progressed greatly in recent years, from investigations of mammalian sperm. Human sperm migrates toward warmer temperatures, ranging from 29 °C to 41 °C. Sperm can detect a temperature gradient as small as 0.014 °C/mm, suggesting that sperm detect temporal changes in temperature rather than spatial differences. Several molecules have been proposed to be sensor molecules, including opsin and transient receptor potential (TRP) channels such as TRPV1, TRPV4, and TRPM8. TRP channels are multimodal sensor for thermal, chemical and mechanical stimuli, but the function of opsins as a thermosensor awaits to be established.
Temperature is a critical environmental factor also for Chlamydomonas cells, which produce small heat shock proteins, chaperonins, and HSP70 heat shock proteins, and also undergo other heat shock responses to cope with heat stress. In response to a cold shock of 4 °C, cells halt proliferation and accumulate starch and sugar. Behavioral responses to avoid stressful warm or cold environments are expected to be present in Chlamydomonas. Although C. moewusii cells are reported to migrate toward warmer temperatures in a 10 °C to 15 °C gradient, there has been no report in which the temperature range was systematically manipulated to examine a relationship with cultivation temperature. A 2019 study demonstrated thermotaxis in Chlamydomonas reinhardtii, and found that between 10 °C and 30 °C Chlamydomonas cells migrated toward lower temperatures independent of cultivation temperature.
In contrast to thermotaxis, phototaxis has been extensively studied in Chlamydomonas. Two flagella of Chlamydomonas beat in a breast-stroke like pattern during forward swimming and, during phototaxis, Chlamydomonas cells make by a turn toward or away from a light source by controlling the balance of the propulsive forces generated by the two flagella. The balance depends on the intraflagellar calcium ion concentration; thus, loss of calcium-dependent control in ptx1 mutants results in a phototaxis defect. The direction of phototaxis in Chlamydomonas depends on the light intensity, but is also affected by intracellular reduction-oxidation (redox) conditions. Cells migrate toward a light source when the light intensity is weak, but the direction reverses under reducing conditions. In contrast, cells swim away from light sources with strong intensity, but the direction reverses under oxidizing conditions.
Swimming speeds
Escape response: Action potentials
In flagellate algae, abrupt changes in light intensity or intense photic stimuli induce rapid flagellar reversal and transient backward swimming. In green algae, this action may be mediated by the contractile root fibre which alters the angle between basal bodies. Cells can also react at speed to unexpected mechanical stimuli. All-or-none contractions in the stalked ciliate Vorticella can occur at rates of 8 cm/s. In some species of heliozoa, axopods can completely retract within 20 ms in order to draw in trapped prey for phagocytosis.
These fast reactions are usually induced by action potentials — unidirectional electrical pulses involving fast, regenerative changes in membrane potential. While all cells display some electrical activity, phylogenetic evidence suggests that the capacity to propagate action potentials may have been an ancestral eukaryotic trait supported by the last eukaryotic common ancestor. These may have emerged in response to accidental membrane damage and sudden calcium influx. Bioelectrical signalling in the form of action potentials occurs orders of magnitude faster than any other signalling modalities, e.g. chemical diffusion, protein phosphorylation etc.
In order to initiate fast escape responses, these may have been coupled directly to the motility apparatus—particularly to flexible, membrane-continuous structures such as cilia and pseudopodia. Loss of voltage-gated sodium/calcium channels is further correlated with loss of cilia in many taxa. In protists, all-or-none action potentials occur almost exclusively in association with ciliary membranes, with the exception of some non-ciliated diatoms. Graded potentials occur in amoebae, also for movement control.
In Chlamydomonas, action-potential-like flagellar currents induce photophobic responses and flagella reversal (via the voltage-gated calcium channel Cav2), while photoreceptor currents elicit much milder responses. Here, a mechanosensory channel of the transient receptor potential family is localized to the ciliary base, while Cav2 is localized only to the distal regions of cilia. In Paramecium, hyperpolarizations increase ciliary beat frequency, while depolarizations have the opposite effect and eventually lead to a ciliary reversal. Depolarizations above a certain threshold result in action potentials, owing to opening of Cav channels located exclusively in the ciliary membrane. Potassium channels — also residing in the membrane — help restore the resting membrane potential.
Eukaryotes manipulate their membrane potential to achieve transitions between different behaviours. Complex bioelectric sequences have been recorded in association with integrated feeding and predation behaviours in Favella. Repetitive behaviours arise from rhythmic spiking. In ciliates, rhythmic depolarizations control fast and slow walking by tentacle-like compound cilia called cirri, enabling escape from dead ends and courtship rituals in conjugating gametes. In Stentor, action potentials produce whole-body contractions. Finally, excitable systems operating close to bifurcations may admit limit cycles, which manifest as repetitive or rhythmic electrical spiking and repetitive behaviours. Ultimately, this may lead to habituation.
Biohybrid microswimmers
Biohybrid microswimmers can be defined as microswimmers that consist of both biological and artificial constituents, for instance, one or several living microorganisms attached to one or various synthetic parts. In 1999, Montemagno and Bachand published an article identifying specific attachment strategies of biological molecules to nanofabricated substrates, enabling the preparation of hybrid inorganic/organic nanoelectromechanical systems (NEMS). They described the production of large amounts of F1-ATPase from the thermophilic bacteria Bacillus PS3 for the preparation of F1-ATPase biomolecular motors immobilized on a nanoarray pattern of gold, copper or nickel produced by electron beam lithography. These proteins were attached to one micron microspheres tagged with a synthetic peptide. Consequently, they accomplished the preparation of a platform with chemically active sites and the development of biohybrid devices capable of converting energy of biomolecular motors into useful work.
Over the past decade, biohybrid microrobots, in which living mobile microorganisms are physically integrated with untethered artificial structures, have gained growing interest to enable the active locomotion and cargo delivery to a target destination. In addition to the motility, the intrinsic capabilities of sensing and eliciting an appropriate response to artificial and environmental changes make cell-based biohybrid microrobots appealing for transportation of cargo to the inaccessible cavities of the human body for local active delivery of diagnostic and therapeutic agents. Active locomotion, targeting and steering of concentrated therapeutic and diagnostic agents embedded in mobile microrobots to the site of action can overcome the existing challenges of conventional therapies. To this end, bacteria have been commonly used with attached beads and ghost cell bodies.
Chlamydomonas reinhardtii is a unicellular green microalga. The wild-type C. reinhardtii has a spherical shape that averages about 10 μm in diameter. This microorganism can perceive the visible light and be steered by it (i.e., phototaxis) with high swimming speeds in the range of 100–200 μm/s. It has natural autofluorescence that permits label-free fluorescent imaging. C. reinhardtii has been actively explored as the live component of biohybrid microrobots for the active delivery of therapeutics. They are biocompatible with healthy mammalian cells, leave no known toxins, mobile in the physiologically relevant media, and allow for surface modification to carry cargo on the cell wall. Alternative attachment strategies for C. reinhardtii have been proposed for the assembly through modifying the interacting surfaces by electrostatic interactions and covalent bonding.
See also
Aquatic locomotion
Bacterial motility
Cytoskeleton
Spirostomum
Squirmer
Vorticella
References
Further reading
Microswimmers
Protista | Protist locomotion | [
"Physics",
"Biology"
] | 5,743 | [
"Physical phenomena",
"Protists",
"Microswimmers",
"Motion (physics)",
"Eukaryotes"
] |
67,846,751 | https://en.wikipedia.org/wiki/Amastigomycota | Amastigomycota or Eufungi is a clade of fungi. It includes all fungi without flagella or centrioles, and with unstacked Golgi apparatus cisternae. Members of this clade are Dikarya and the traditional paraphyletic assemblage "Zygomycota", now divided into several monophyletic phyla.
Classifications
Cavalier-Smith (1981)
Kingdom (or Subkingdom) Eufungi
Phylum Hemiascomycota
Phylum Ustomycota
Phylum Zygomycota
Phylum Ascomycota
Phylum Uredomycota
Phylum Basidiomycota
At the time, the monophyly of Fungi (Eumycota) was not fully certain. Cavalier-Smith considered one scenario where Eufungi could be ancestral or basal to other eukaryotes due to their relatively simple cytology and small genome, though he favoured the hypothesis of fungal monophyly, which is now the consensus.
Phylogenetic tree
References
Fungus taxonomy
Fungi by classification
Mycology | Amastigomycota | [
"Biology"
] | 232 | [
"Fungi",
"Eukaryotes by classification",
"Fungi by classification",
"Mycology"
] |
67,848,628 | https://en.wikipedia.org/wiki/COVID-19%20vaccine%20card | A COVID-19 vaccine card is a record often given to those who have received a COVID-19 vaccine showing information such as the date(s) one has received the shot(s) and the brand of vaccine one has received, sometimes including the lot number. The card also contains information identifying the recipient and the location where the shot was given. Depending on the country, it could serve as an official document verifying one has received vaccination, which could be required by some institutions, such as a school or workplace, when boarding a cruise ship, or when crossing an international border, as proof that one has been vaccinated.
Some countries issue digital records while others issue paper records. In some European Union member states, citizens might choose to have a digital record, a piece of paper, or both.
By country
Australia
In Australia, vaccine providers are required to report to the Australian Immunisation Register no later than 10 days after a vaccination is given. People who have been vaccinated can either access a digital record of vaccination on a smartphone, or request a paper copy of their vaccination record.
Austria
In October 2021, Austria has emitted 43.058.575 out of 591.728.344 EU Digital COVID Certificate emitted within the EEA.
Brazil
In December 2020, the Brazilian senate approved digital cards.
Canada
In Canada, vaccination certificates are issued by the health authorities of each province and territory. Vaccine certificate/passport systems were introduced in the provinces of British Columbia, Manitoba, and Quebec starting in September 2021.
Since October 2021, all vaccination certificates follow a single national design standard, and include a QR Code for validation in accordance with the international SMART Health Card framework.
China
China uses digital vaccine certificates for cross border travel. Launched in March 2021, the system uses QR codes that show the individual's vaccination status as well as RT-PCR test and Rapid antigen test results and is built atop Tencent's WeChat platform. Prior to this, QR health codes were required for public transport and access to public spaces in the country. The platform also allows for digital contact tracing and shows a green code for users who have not been in contact with infected people. The system has sparked concerns over government surveillance and privacy of users.
Egypt
Those who have received two doses of a vaccine receive a certificate that allows them to travel. Vaccinated users can either receive a vaccine card or register online after receiving both doses to get a certificate. In October 2021, the government announced the launch of a mobile app that would enable the verification of an individual's vaccination status using a QR code instead of carrying a certificate.
France
Vaccine certificates in France are issued with a QR code — an EU Digital COVID Certificate — scanned onto the country's contact tracing app, TousAntiCovid. The app, which can also scan the QR Code of a test result, allows those vaccinated to show their vaccination status on their smartphone.
In October 2021, France has emitted 136.901.354 out of 591.728.344 EU Digital COVID Certificate emitted within the EEA.
For vaccine certificates, there are 72 186 091 French vaccine certificate for 437 509 564 EU ones (that is %).
Germany
In Germany, vaccination is documented in the International Certificate of Vaccination or Prophylaxis, commonly known as "gelber Impfpass" (yellow vaccination passport) The EU Digital COVID Certificate is also available, and officially recognized. It is regularly issued since July 1, 2021 in vaccination centers for people receiving their vaccination and in pharmacies for those who were vaccinated before July.
In October 2021, Germany has emitted 123.254.466 out of 591.728.344 EU Digital COVID Certificate emitted within the EEA.
For vaccine certificates, there are 119.750.418 German vaccine certificates for 437 509 564 EU ones (that is %).
India
In India, once a person receives a dose of vaccine, a digital certificate is issued that can either be downloaded from the CoWIN web portal, from the UMANG mobile app, from the Aarogya Setu mobile app or it can directly be downloaded on to citizen's digital document wallet Digilocker. A provisional certificate is issued after the first dose, which contains the vaccinated person's personal details, the vaccine used, the vaccinator's name, and the window for the next dose. A final certificate is issued after the second dose. For those traveling abroad, an option to link their passport is available.
Iran
Iran made issuing digital vaccine card mandatory for full vaccine administration.
Indonesia
In Indonesia, every person who have received at least a dose of vaccine will receive a vaccine card and vaccination certificate which can be downloaded from PeduliLindungi mobile app. Vaccination card contains the vaccinated person's personal details, the vaccine used, the vaccinator's name, the batch number of the vaccine used, and the window for the next dose.
Ireland
On 12 July 2021, fully vaccinated people in Ireland began receiving their EU Digital COVID Certificates via email or post. The EU Digital COVID Certificate in Ireland was initially used for international travel as restrictions into and out of the country eased from 19 July, but was also used in restaurants, hotels and bars as proof of vaccination to gain access to indoor hospitality, as well as in nightclubs, indoor live entertainment, cinemas, theatres and gyms. Requirements on the use of vaccine certificates domestically were scrapped in January 2022.
The Health Service Executive (HSE) issues a vaccine record card to those receiving a COVID-19 vaccine in Ireland that provides reminders for a follow-up appointment. The card contains the recipient's name, the dates on which the two doses were administered, the name of the vaccine, and its batch number. The vaccine record card could also be used as proof of vaccination.
Israel
In February 2021, Israel rolled out its Green Pass system for those who had completed a week after taking their second dose of the vaccine or those who had recovered from the virus and were ineligible to take the vaccine. The Green Pass is issued by the Ministry of Health. It is a secure digital certificate that is required to enter certain crowded areas such as restaurants, gyms, theatres, and synagogues that have registered themselves as part of the system. A vaccinated person has to either download the app or use the website to download the certificate. A QR Code is provided to allow the pass to be verified. When launched, the pass was valid for six months from the date of the second dose of the vaccine. In May, the Ministry extended the validity of the Green Pass until the end of the year.
Italy
Italy uses the EU Digital COVID Certificate, which is also referred to as the Green Pass.
In October 2021, Italy has emitted 97.058.162 out of 591.728.344 EU Digital COVID Certificate emitted within the EEA.
New Zealand
Under the New Zealand Government's COVID-19 Protection Framework, a vaccine pass may be required for access to some non-essential venues such as restaurants, sports centres, and faith-based gatherings. The pass contains an individual's name, date of birth, and a QR code. Some venues may choose to check the name on the pass with the individual's photo ID, but this is not required by law.
Philippines
Upon being vaccinated with a COVID-19 vaccine, the local government unit (LGU) or recognized private healthcare providers issue a vaccine card that shall act as proof of vaccination. The Department of Information and Communications Technology (DICT) is presently working with the Inter-Agency Task Force for the Management of Emerging Infectious Diseases (IATF-EID) for a centralized registry for COVID-19 vaccinated residents under a common digital vaccine ID that shall feature a unique QR code and a person's photograph.
Since 2021, the Bureau of Quarantine of the Philippines has updated the existing International Certificate of Vaccination (ICV) that shall include information for being vaccinated from COVID-19 and currently being issued to Overseas Filipino Workers (OFW) and residents going on international travel. The new ICV contains a unique QR code, which allows the verification of the authenticity of the said certificate. At presently, the ICV can only be issued to Filipino citizens and residents who have been vaccinated with a COVID-19 vaccine listed under the Emergency Use Listing (EUL) by the World Health Organization (WHO).
South Africa
Current South African COVID-19 Vaccination Record Cards Contain Identification information and provision for 3 doses of vaccines.
The or Digital Vaccine Certificates can be assessed at https://vaccine.certificate.health.gov.za/
The Digital Certificate has the Department of Health Logo at the top with a QR Code on the right intended to be used in the future, said to be available by the end of 2021.
There 3 sections to the Certificate.
The first section contains identification data including ID Document Used, ID Number, First Name, Surname and Date Of Birth.
The second section contains vaccine dose information as in Vaccine Received, Vaccine Date and Proof of vaccination code. This will be on there twice if the individual has received more than one dose.
The final section contains a card expiration date.
Singapore
After receiving each vaccination dose, an individual will be provided a physical vaccination card that certifies an individual's vaccination status. This information is also recorded on the National Immunisation Registry and is viewable through the Ministry of Health's HealthHub application. The ability to verify one's vaccination status was also added to the TraceTogether application in version 2.11. TraceTogether is used to verify one's vaccination status when entering businesses, and for contact tracing purposes. From 26 April 2022 onwards, there is no need to verify one's vaccination status using the TraceTogether application when entering businesses, unless at large events or at certain nightlife establishments.
Outbound travellers who have been fully vaccinated in Singapore can also obtain a Vaccination HealthCert, which is a digitally verifiable proof of vaccination. When required, foreign authorities can use the QR codes in the Vaccination HealthCert to verify that it has not been tampered with.
Sweden
As of the 24th of August, the Swedish government have discussed implementing a vaccine card, restricting access to music and culture events to people with two vaccine doses.
Switzerland
Digital and hard copy versions of COVID-19 vaccine cards are issued by the respective cantons upon full vaccination. The federal government provides an app and registration site, as well as QR coded documents for immunised Swiss residents. Such certification is valid for 365 days and must be provided upon entering certain premises and/or for international travel. So far, Switzerland has fully adhered to EU protocols, and digital EU vaccine certificates are approved in Switzerland, as are some of the Asian vaccines for certain travelers.
Taiwan
After inoculation, individuals receive an official yellow card like the one above that records individuals' vaccination information.
United Kingdom
Those receiving a COVID-19 vaccine in the United Kingdom (except Scotland) are given a card the size of a credit card that provides reminders for a follow-up appointment. The card contains the recipient's name, the dates on which the two doses were administered, the name of the vaccine, and its batch number. Vaccinated people looking to travel abroad can take a printout of their certificate from the website of the National Health Service (NHS). The QR Code present on the vaccination certificate can be used to store the details on a smartphone app.
Prime Minister Boris Johnson announced in July 2021 that once all adults have received their second dose of the vaccine, vaccine cards would be mandatory to gain access to crowded places such as nightclubs.
United States
Those who receive their vaccination in the United States are given a card with the Centers for Disease Control and Prevention (CDC) and the Health and Human Services (HHS) logos that records their name, the date of each dose, and the brand of the vaccine they have received. In October 2023, the CDC announced it would no longer be issuing COVID-19 vaccine cards.
Some states provide a digital record of vaccination to their residents, using a QR code that can be verified with a scanner app. New York has the Excelsior Pass which also records the results of COVID-19 tests while California has the California Digital COVID-19 Vaccine Record.
Issues
Posting on social media
Many vaccine recipients have posted pictures of their vaccine cards on social media. This risks the exposure of personal information that is unsafe to share with the public.
Forgery
Fake vaccine cards have been sold on the Internet. Sales of these cards have increased substantially since some businesses started requiring proof of vaccination to gain entry. Existing laws prohibit the sale and use of these forgeries.
In September 2021, a woman in the United States was arrested for using a fake vaccine card to bypass mandatory vaccination requirements. The arrest was made after it came to light that the card said Maderna instead of Moderna in the vaccine name. The same month, U.S. Customs and Border Protection seized more than 6,000 counterfeit vaccine cards across the country with two mail packages in Pittsburgh originating from China. Prior to this, several vendors were found selling fake vaccine cards on e-commerce platforms such as Amazon.
In Russia, a black market for fake vaccine cards emerged soon after the government started requiring them for various activities.
At a Dutch nightclub, clubgoers presenting the Q-codes of digital certificates belonging to others led to an outbreak that infected 160 people.
Theft of authentic cards
A Chicago pharmacist sold 125 authentic vaccination cards online to 11 different buyers and was charged with 12 counts of theft of government property, with a potential sentence of ten years in prison for each count. A contractor at the Pomona Fairplex in California stole 528 blank vaccination cards and was charged with felony grand theft.
See also
Immunity passport
Vaccine passports during the COVID-19 pandemic
Ahnenpass
References
External links
Software associated with the COVID-19 pandemic
Identity documents
Vaccination | COVID-19 vaccine card | [
"Biology"
] | 2,989 | [
"Vaccination"
] |
67,852,811 | https://en.wikipedia.org/wiki/Bug%20algorithm | Bug algorithm is a class of algorithm that helps robots deal with motion planning.
Basic assumptions
The robot is treated as a point inside a 2D world.
The obstacles (if any) are unknown and nonconvex.
There are clearly defined starting point and goal.
The robot is able to detect obstacle boundary from a distance of known length.
The robot always knows the direction and how far (in terms of Euclidean distance) it is from the goal.
Algorithm
The most basic form of Bug algorithm (Bug 1) is as follows:
The robot moves towards the goal until an obstacle is encountered.
Follow a canonical direction (clockwise) until the robot reaches the location of initial encounter with the obstacle (in short, walking around the obstacle).
The robot then follows the obstacle's boundary to reach the point on the boundary that is closest to the goal.
Go back to step 1. Repeat this until the goal is reached.
See also
Pathfinding
Motion planning
References
Robot kinematics | Bug algorithm | [
"Engineering"
] | 197 | [
"Robotics engineering",
"Robot kinematics"
] |
67,855,030 | https://en.wikipedia.org/wiki/Semrush | Semrush Holdings, Inc. is an American public company that has a SaaS platform known as Semrush. The platform is used for keyword research, competitive analysis, site audits, backlink tracking, and comprehensive online visibility insights. The keyword research tool provides various data points on each keyword. The platform also collects information about online keywords gathered from Google and Bing search engines. It was released by Boston-based company Semrush Inc, founded by Oleg Shchegolev and Dmitri Melnikov.
As of 2022, the company has 1000+ employees and offices in Barcelona, Belgrade, Berlin, Yerevan, Limassol, Prague, Warsaw, Amsterdam, Austin, Boston, Dallas, Philadelphia, and Trevose. It went public in March 2021 and trades on .
History
Semrush was first released as Seodigger before becoming an extension of Firefox, then renamed SeoQuake Company in 2007, before landing on SEMrush (the acronym SEM stands for Search engine marketing).
In April 2018, the company received $40 million in funding as part of a financing transaction co-led by venture capital firms Greycroft, E.ventures and Siguler Guff, in preparation for its expansion into various platforms of research, including those owned by Amazon, Microsoft, and Baidu.
In December 2020, the company rebranded with a new visual identity, updating its name from "SEMrush" to "Semrush".
In March 2021, Semrush had an initial public offering and went public on NYSE under the symbol . The S-1 form revealed that the company had sales of $213 million and more than 82,000 customers.
Semrush's founders are Russian, and relocated to the US in 2017. In response to Russia's invasion of Ukraine in 2022, the company ceased all operations in Russia and offered relocation to Russian-based staff to other European countries.
In June 2022, the company launched a beta tool for content generation called Content Outline Builder. The tool will suggest ideas for article writing and blog posts. Semrush also announced on June 27, 2022, that their Backlinks insights data is now integrated with SurferSEO, a marketing tool focused on content creation.
Mergers and acquisitions
In 2022, Semrush acquired Backlinko from Brian Dean. In March 2022, Semrush acquired intelligence and sales platform Kompyte, marking the companies first acquisition of a non search focused platform.
In March 2023, SEO community Traffic Think Tank was also acquired.
In October 2024, Semrush acquired Third Door Media, publisher of Search Engine Land.
References
Internet search
Online databases
Search engine optimization companies
Internet terminology
Search engine optimization
2008 software
Internet properties established in 2008
2021 initial public offerings
Companies based in Boston
Companies_listed_on_the_New_York_Stock_Exchange | Semrush | [
"Technology"
] | 599 | [
"Computing terminology",
"Internet terminology"
] |
67,855,755 | https://en.wikipedia.org/wiki/Wilson%20doctrine%20%28economics%29 | In economic theory, the Wilson doctrine (or Wilson critique) stipulates that game theory should not rely excessively on common knowledge assumptions. Most prominently, it is interpreted as a request for institutional designs to be "detail-free". That is, mechanism designers should offer solutions that do not depend on market details (such as distributions or functional forms of payoff relevant signals) because they may be unknown to practitioners or are subject to intractable change. The name is due to Nobel laureate Robert Wilson, who argued:
Game theory has a great advantage in explicitly analyzing the consequences of trading rules that presumably are really common knowledge; it is deficient to the extent it assumes other features to be common knowledge, such as one agent's probability assessment about another’s preferences or information. I foresee the progress of game theory as depending on successive reductions in the base of common knowledge required to conduct useful analyses of practical problems. Only by repeated weakening of common knowledge assumptions will the theory approximate reality.
While the above quote is often seen as the Wilson doctrine, mechanism design researchers derive an insistence on detail-free mechanisms from it. For instance, Partha Dasgupta and Eric Maskin, as well as Mark Satterthwaite and Steven Williams, attribute this insistence to Wilson. This interpretation might also go back to another paper by Wilson in which he praises the double auction because it "does not rely on features of the agents' common knowledge, such as their probability assessment". While Wilson himself agrees with the spirit of demanding detail-free mechanisms, he is surprised to be credited for it. In line with the above quote, Dirk Bergemann and Stephen Morris see the doctrine as a reminder of John Harsanyi's insight that common knowledge assumptions can be made explicit (and then relaxed) by enriching the type space with beliefs. This interpretation gave rise to their notion of robust mechanism design. An alternative approach to robust mechanism design assumes non-probabilistic uncertainty. For instance, Gabriel Carroll has a series of papers in which the principal evaluates outcomes on a worst-case basis.
References
Mechanism design | Wilson doctrine (economics) | [
"Mathematics"
] | 427 | [
"Game theory",
"Mechanism design"
] |
67,857,583 | https://en.wikipedia.org/wiki/IC%201913 | IC 1913 is a barred spiral galaxy in the constellation Fornax. It belongs to the Fornax Cluster, which contains approximately 200 galaxies.
It is 66.5 million light years distant from Earth, and based on its size on the night sky and distance, it is 37,000 light years in diameter. It was discovered by DeLisle Stewart in 1899.
It is visible from southern hemisphere using telescope, but not with a naked eye.
See also
IC 1919
NGC 1399
NGC 1427A
References
Barred spiral galaxies
Fornax Cluster
Fornax | IC 1913 | [
"Astronomy"
] | 114 | [
"Fornax",
"Constellations"
] |
58,303,367 | https://en.wikipedia.org/wiki/Relative%20fat%20mass | Relative Fat Mass (RFM) is a simple formula for the estimation of overweight or obesity in humans that requires only a calculation based on a ratio of height and waist measurements.
High body fat is associated with increased risks of poor health and early mortality. RFM is a simple anthropometric procedure that is claimed to be more convenient than body fat percentage and more accurate than the traditional body mass index (BMI).
The ratio of the patient's height and waist measurement, both in meters, is multiplied by 20 before being subtracted from a number (shown in bold below) that adjusts for differences in gender and height:
RFM for adult males: 64 – 20 × (height / waist circumference)
RFM for adult females: 76 – 20 × (height / waist circumference)
Although generally validated on a database of some 12,000 adults, RFM has not yet been evaluated in longitudinal studies of large populations to identify normal or abnormal RFM in relation to obesity-related health problems.
See also
Body mass index (BMI)
Body fat percentage (BFP)
Body roundness index (BRI)
Body water (TBW)
Corpulence index (CI)
References
Body shape
Classification of obesity
Human height
Human body weight
Medical signs
Ratios | Relative fat mass | [
"Mathematics"
] | 263 | [
"Arithmetic",
"Ratios"
] |
58,303,697 | https://en.wikipedia.org/wiki/Local%20Rapid%20Evaluation%20of%20Atmospheric%20Conditions%20System | The Local Rapid Evaluation of Atmospheric Conditions (L-REAC) System was a computerized weather sensor system designed by the U.S. Army Research Laboratory (ARL) that became operational in 2011.
Purpose
The system was designed to warn soldiers and civilians of airborne threats, such as chemical attacks or toxic spills. The purpose of L-REAC was to provide wind monitoring and modeling, which acted as a decision aid for soldiers facing environmental hazards.
History
A research meteorologist at ARL developed the first L-REAC prototype. After conducting a survey of commercially available technology from 2003–2007, ARL identified a need for a local atmospheric assessment system. Three studies conducted at White Sands Missile Range, New Mexico, in the early 2000s revealed a requirement for emergency first responders to have up-to-date atmospheric information on local conditions.
During the mid 2000s, it was also reported that U.S. Army soldiers stationed in Iraq were experiencing toxic fumes while working near burn pits. The L-REAC concept was produced from 2009-2011 at White Sands Missile Range as part of a study investigating the airflow around an urban building and small building clusters.
In June 2017, ARL licensed the technology to Diamond B Technology Solutions in Billings, Montana. Rebranded as LR-x, the system assisted in tracking environmental emergencies, such as wildfire smoke during fire suppression efforts.
Operation
The L-REAC provided 3D weather models that generated wind field and plume outputs, displaying near real-time meteorological data on a map background. The models included terrain and buildings, and displayed danger zones and weather conditions (i.e. wind speed, wind direction, temperature, and relative humidity).
References
2011 establishments in the United States
Weather prediction
United States Army equipment | Local Rapid Evaluation of Atmospheric Conditions System | [
"Physics"
] | 356 | [
"Weather",
"Weather prediction",
"Physical phenomena"
] |
58,306,941 | https://en.wikipedia.org/wiki/Technology%20readiness%20level | Technology readiness levels (TRLs) are a method for estimating the maturity of technologies during the acquisition phase of a program. TRLs enable consistent and uniform discussions of technical maturity across different types of technology. TRL is determined during a technology readiness assessment (TRA) that examines program concepts, technology requirements, and demonstrated technology capabilities. TRLs are based on a scale from 1 to 9 with 9 being the most mature technology.
TRL was developed at NASA during the 1970s. The US Department of Defense has used the scale for procurement since the early 2000s. By 2008 the scale was also in use at the European Space Agency (ESA).
The European Commission advised EU-funded research and innovation projects to adopt the scale in 2010. TRLs were consequently used in 2014 in the EU Horizon 2020 program. In 2013, the TRL scale was further canonized by the International Organization for Standardization (ISO) with the publication of the ISO 16290:2013 standard.
A comprehensive approach and discussion of TRLs has been published by the European Association of Research and Technology Organisations (EARTO). Extensive criticism of the adoption of TRL scale by the European Union was published in The Innovation Journal, stating that the "concreteness and sophistication of the TRL scale gradually diminished as its usage spread outside its original context (space programs)".
Definitions
Assessment tools
A Technology Readiness Level Calculator was developed by the United States Air Force. This tool is a standard set of questions implemented in Microsoft Excel that produces a graphical display of the TRLs achieved. This tool is intended to provide a snapshot of technology maturity at a given point in time.
The Defense Acquisition University (DAU) Decision Point (DP) Tool originally named the Technology Program Management Model was developed by the United States Army. and later adopted by the DAU. The DP/TPMM is a TRL-gated high-fidelity activity model that provides a flexible management tool to assist Technology Managers in planning, managing, and assessing their technologies for successful technology transition. The model provides a core set of activities including systems engineering and program management tasks that are tailored to the technology development and management goals. This approach is comprehensive, yet it consolidates the complex activities that are relevant to the development and transition of a specific technology program into one integrated model.
Uses
The primary purpose of using technology readiness levels is to help management in making decisions concerning the development and transitioning of technology. It is one of several tools that are needed to manage the progress of research and development activity within an organization.
Among the advantages of TRLs:
Provides a common understanding of technology status
Risk management
Used to make decisions concerning technology funding
Used to make decisions concerning transition of technology
Some of the characteristics of TRLs that limit their utility:
Readiness does not necessarily fit with appropriateness or technology maturity
A mature product may possess a greater or lesser degree of readiness for use in a particular system context than one of lower maturity
Numerous factors must be considered, including the relevance of the products' operational environment to the system at hand, as well as the product-system architectural mismatch
TRL models tend to disregard negative and obsolescence factors. There have been suggestions made for incorporating such factors into assessments.
For complex technologies that incorporate various development stages, a more detailed scheme called the Technology Readiness Pathway Matrix has been developed going from basic units to applications in society. This tool aims to show that a readiness level of a technology is based on a less linear process but on a more complex pathway through its application in society.
History
Technology readiness levels were conceived at NASA in 1974 and formally defined in 1989. The original definition included seven levels, but in the 1990s NASA adopted the nine-level scale that subsequently gained widespread acceptance.
Original NASA TRL Definitions (1989)
Level 1 – Basic Principles Observed and Reported
Level 2 – Potential Application Validated
Level 3 – Proof-of-Concept Demonstrated, Analytically and/or Experimentally
Level 4 – Component and/or Breadboard Laboratory Validated
Level 5 – Component and/or Breadboard Validated in Simulated or Realspace Environment
Level 6 – System Adequacy Validated in Simulated Environment
Level 7 – System Adequacy Validated in Space
The TRL methodology was originated by Stan Sadin at NASA Headquarters in 1974. Ray Chase was then the JPL Propulsion Division representative on the Jupiter Orbiter design team. At the suggestion of Stan Sadin, Chase used this methodology to assess the technology readiness of the proposed JPL Jupiter Orbiter spacecraft design. Later Chase spent a year at NASA Headquarters helping Sadin institutionalize the TRL methodology. Chase joined ANSER in 1978, where he used the TRL methodology to evaluate the technology readiness of proposed Air Force development programs. He published several articles during the 1980s and 90s on reusable launch vehicles utilizing the TRL methodology.
These documented an expanded version of the methodology that included design tools, test facilities, and manufacturing readiness on the Air Force Have Not program. The Have Not program manager, Greg Jenkins, and Ray Chase published the expanded version of the TRL methodology, which included design and manufacturing. Leon McKinney and Chase used the expanded version to assess the technology readiness of the ANSER team's Highly Reusable Space Transportation (HRST) concept. ANSER also created an adapted version of the TRL methodology for proposed Homeland Security Agency programs.
The United States Air Force adopted the use of technology readiness levels in the 1990s.
In 1995, John C. Mankins, NASA, wrote a paper that discussed NASA's use of TRL, extended the scale, and proposed expanded descriptions for each TRL. In 1999, the United States General Accounting Office produced an influential report that examined the differences in technology transition between the DOD and private industry. It concluded that the DOD takes greater risks and attempts to transition emerging technologies at lesser degrees of maturity than does private industry. The GAO concluded that use of immature technology increased overall program risk. The GAO recommended that the DOD make wider use of technology readiness levels as a means of assessing technology maturity prior to transition.
In 2001, the Deputy Under Secretary of Defense for Science and Technology issued a memorandum that endorsed use of TRLs in new major programs. Guidance for assessing technology maturity was incorporated into the Defense Acquisition Guidebook. Subsequently, the DOD developed detailed guidance for using TRLs in the 2003 DOD Technology Readiness Assessment Deskbook.
Because of their relevance to Habitation, 'Habitation Readiness Levels (HRL)' were formed by a group of NASA engineers (Jan Connolly, Kathy Daues, Robert Howard, and Larry Toups). They have been created to address habitability requirements and design aspects in correlation with already established and widely used standards by different agencies, including NASA TRLs.
More recently, Dr. Ali Abbas, Professor of chemical engineering and Associate Dean of Research at the University of Sydney and Dr. Mobin Nomvar, a chemical engineer and commercialisation specialist, have developed Commercial Readiness Level (CRL), a nine-point scale to be synchronised with TRL as part of a critical innovation path to rapidly assess and refine innovation projects to ensure market adoption and avoid failure.
In the European Union
The European Space Agency adopted the TRL scale in the mid-2000s. Its handbook closely follows the NASA definition of TRLs. In 2022, the ESA TRL Calculator was released to the public. The universal usage of TRL in EU policy was proposed in the final report of the first High Level Expert Group on Key Enabling Technologies, and it was implemented in the subsequent EU framework program, called H2020, running from 2013 to 2020. This means not only space and weapons programs, but everything from nanotechnology to informatics and communication technology.
See also
References
Online
External links
Technology Readiness Levels (TRL) NASA
Technology Readiness Levels Introduction NASA archive via Wayback Machine
DNV Recommended_Practices (Look for DNV-RP-A203)
UK MoD Acquisition Operating Framework guide to TRL (requires registration)
Technology assessment
Technology transfer
Management cybernetics | Technology readiness level | [
"Technology"
] | 1,628 | [
"Science and technology studies",
"nan",
"Technology assessment"
] |
58,307,276 | https://en.wikipedia.org/wiki/Quantum%20dimer%20magnet | In condensed matter physics, the quantum dimer magnet state is one in which quantum spins in a magnetic structure entangle to form a singlet state. These entangled spins act as bosons and their excited states (triplons) can undergo Bose-Einstein condensation (BEC). The quantum dimer system was originally proposed by Matsubara and Matsuda as a mapping of the lattice Bose gas to the quantum antiferromagnet. Quantum dimer magnets are often confused as valence bond solids; however, a valence bond solid requires the breaking of translational symmetry and the dimerizing of spins. In contrast, quantum dimer magnets exist in crystal structures where the translational symmetry is inherently broken. There are two types of quantum dimer models: the XXZ model and the weakly-coupled dimer model. The main difference is the regime in which BEC can occur. For the XXZ model (commonly referred to as the magnon BEC), the BEC occurs upon cooling without a magnetic field and manifests itself as a symmetric dome in the field versus temperature phase diagram centered about H = 0. The weakly-coupled dimer model does not magnetically order in zero magnetic field, but instead orders upon the closing of the spin gap, where the BEC regime begins and is a dome centered at non-zero field.
Quantum dimer systems are considered to be of interest due to their relatively simple interactions and their BEC state is of interest as a novel playground for testing BEC physics. In addition, the BEC state of the quantum dimer magnet is thought to be a spin superfluid which could allow for the transfer of spin information over long distances without loss.
Bose-Einstein condensation in the weakly-coupled dimer model
The Bose-Einstein condensation in quantum dimer systems is, at its essence, a field-induced magnetically ordered state that comes about from the Zeeman splitting of the triplet states. The bosons of the Bose-Einstein condensate can be thought of as the component of the spin parallel to the applied magnetic field, reaching a maximum when the spins become polarized by the field. The difference between the Bose-Einstein condensation and a typical ordered state is the spontaneous breaking of the spin's U(1) symmetry (i.e. the circular symmetry transverse to an applied magnetic field). This spontaneous symmetry breaking gives rise to a Goldstone boson that is measureable via a inelastic neutron scattering (amongst other techniques).
References
Condensed matter physics | Quantum dimer magnet | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 524 | [
"Phases of matter",
"Condensed matter physics",
"Matter",
"Materials science"
] |
58,318,372 | https://en.wikipedia.org/wiki/European%20Women%20in%20Mathematics | European Women in Mathematics (EWM) is an international association of women working in the field of mathematics in Europe. The association participates in political and strategic work to promote the role of women in mathematics and offers its members direct support. Its goals include encouraging women to study mathematics and providing visibility to women mathematicians. It is the "first and best known" of several organizations devoted to women in mathematics in Europe.
Mission
European Women in Mathematics aims to encourage women to study mathematics, support women in their careers, provide a meeting place for like-minded people and highlight and make women mathematicians visible. In this way, and by promoting scientific communication and working with groups and organisations with similar goals, they spread their vision of mathematics and science.
Mentorship
EWM has a mentoring programme which can be joined at any time of the year. EWM brings together a younger and a more experienced member to share different experiences and perspectives for motivation and inspiration.
Grants
EWM awards travel grants for female mathematicians every year. The travel grants are awarded to EWM members who are at an early stage of their career or work in a developing country and who need financial resources (travel and/or accommodation, up to 400 EUR) to attend and speak at an important conference in their field of expertise.
Regular Activities
Every other year, EWM holds a general meeting and a summer school. A newsletter is published at least twice a year, EWM has a website, a Facebook group and an e-mail network. EWM coordinates a mentoring programme and awards a travel grant twice a year.
General Meetings
EWM hold a General Meeting every other year in the form of a week-long conference with a scientific program of mini-courses on mathematical topics, discussions on the situation of women in the field and a General Assembly.
General meetings have been held in Paris (1986), Copenhagen (1987), Warwick (1988), Lisbon (1990), Marseilles (1991), Warsaw (1993), Madrid (1995), Trieste ICTP (1997), Hannover (1999), Malta (2001), Luminy (2003), Volgograd (2005), Cambridge (2007), Novi Sad (2009), Barcelona (2011), Bonn (2013), Cortona (2015), and Graz (2018).
Activities at international conferences
EWM holds satellite conferences to the European Congress in Mathematics and takes part in ICWM International Conference of Women in Mathematics, International Congress of Women Mathematicians and now World Meeting for Women Mathematicians.
History
Although the group that became EWM began holding informal meetings as early as 1974,
EWM was founded as an organization in 1986 by Bodil Branner, Caroline Series, Gudrun Kalmbach, Marie-Françoise Roy, and Dona Strauss, inspired by the activities of the Association for Women in Mathematics in the USA. It was established as an association under Finnish law in 1993 with its seat in Helsinki.
In fact, the basic structure defining the convenor, standing committee and coordinators was established between 1987 and 1991. An EWM email net was set up in 1994 followed by a web page in 1997.
The organization has a Scientific Committee, jointly with the European Mathematical Society and its Committee on Women in Mathematics.
Convenors and Deputies
Similar Societies
There are many similar societies like the "European Women in Mathematics" society that celebrate women in Mathematics. For instance:
Women in Mathematics
International Mathematical Union (IMU) Committee for Women in Mathematics
EMS Women in Mathematics Committee
EMS/EWM Scientific Committee
Femmes et mathématiques
EWM - The Netherlands
LMS Women in Mathematics Committee
Korea Women in Mathematical Sciences
AWM, Association for Women in Mathematics
Women in Math Project
AWSE Association of Women in Science and Education in Russian
Mathematics
The European Mathematical Information Service (EMIS)
The International Mathematical Union (IMU)
Math Archives WWW server
European Union Information
EMS, European Mathematical Society
References
External links
Official website
Mathematical societies
Organizations established in 1986
Organizations for women in science and technology
Pan-European learned societies
Women in mathematics | European Women in Mathematics | [
"Technology"
] | 828 | [
"Organizations for women in science and technology",
"Women in science and technology",
"Women in mathematics"
] |
58,318,949 | https://en.wikipedia.org/wiki/The%20Great%20Bridge%20%28book%29 | The Great Bridge: The Epic Story of the Building of the Brooklyn Bridge is a 1972 book about the construction of the Brooklyn Bridge written by popular historian David McCullough. It provides a history of the engineering that went into the building of the bridge as well as the toils John A. Roebling, the designer of the bridge, went through with his son Washington Roebling to bring the bridge to its completion. The book went on to win two awards in 1973; the Certificate of Merit Municipal Art Society, NY, and the New York Diamond Jubilee Award.
The documentary film, Brooklyn Bridge, released in 1981 by Ken Burns, Roger Sherman, Buddy Squires, and Amy Stechler drew inspiration from McCullough's work. He was also chosen to be the narrator for the film.
References
External links
Official Site at Simon & Schuster
The Great Bridge from WorldCat
Presentation by McCullough on The Great Bridge, September 17, 2002, C-SPAN
1972 non-fiction books
History books about civil engineering in the United States
Books by David McCullough
Simon & Schuster books
Books about New York City
Brooklyn Bridge | The Great Bridge (book) | [
"Engineering"
] | 226 | [
"History books about civil engineering in the United States",
"Civil engineering"
] |
58,319,355 | https://en.wikipedia.org/wiki/April%20Salome%20Forest%20Management%20Area | April Salumei Forest Management Area also known as April Salome Rainforest is a forest management area in April — Salumei tropical forest covering over 600,000 hectares in Ambunti-Dreikikir District of East Sepik Province, of Papua New Guinea. The forest is located in the basins of two rivers: April and Salumei. The town of Ambunti serves as a gateway to the April Salome Forest Management Area.
The project area has previously been recognised as an exceptional biodiversity hotspot by the Climate Community and Biodiversity Standard (SCS, 2011). Before becoming a carbon project, the area was planned to be cleared for logging.
The project also channels climate finance to the community via a benefit sharing agreement that provides 60% of the revenue from sale of offsets to autonomous local landowner groups, helping reduce poverty and enhance the wellbeing of local communities.
The April Salumei Working Group, formed to assist with managing the project, provides employment opportunities to the local community. The project promotes culturally inclusive, sustainable community development via a new five-year Sustainable Development Plan, agreed by locals.
Previous project activities have delivered benefits including:
Providing over 10,000 native eaglewood trees for village areas for sustainable agriculture
Providing 1,000 solar powered lights to community schools, health centres and families to provide affordable, sustainable energy
Created 18 jobs for community members
Providing funds to improve 15 local schools to help promote quality education.
Population
It is estimated that about 20,000 people are living in this area in 164 forest-dependent communities. Populated places include Nakek and Uwu.
Geography
April Salumei Forest Management Area is located in the Sepik river basin. Sepik tributary, the April river is the major river in the area.
See also
Papua New Guinea Forestry Authority
Deforestation in Papua New Guinea
References
Forestry in Papua New Guinea
Populated places in East Sepik Province
Rainforests
Tropical rainforests
Sustainable forest management
Habitat management equipment and methods
Forest certification
Forest governance
Forest conservation
Community-based forestry | April Salome Forest Management Area | [
"Biology"
] | 403 | [
"Tropical rainforests",
"Ecosystems"
] |
58,319,684 | https://en.wikipedia.org/wiki/The%20Johnstown%20Flood%20%28book%29 | The Johnstown Flood: The Incredible Story Behind One of the Most Devastating Disasters America Has Ever Known is a 1968 book written by popular historian David McCullough about the Great Flood of 1889 which devastated the town of Johnstown, Pennsylvania. For this, his first book, McCullough spent time speaking with individuals who lived through the flood on top of his other research in preparation for writing. Upon its publication The Johnstown Flood rekindled national interest in the flood and was the catalyst to McCullough's accomplished career. Following the success of his book, McCullough decided to devote his time entirely toward writing.
See also
The Johnstown Flood (1989 film)
References
External links
Official Site at Simon & Schuster
The Johnstown Flood from WorldCat
1968 non-fiction books
History books about civil engineering in the United States
Books by David McCullough
Simon & Schuster books
History of Johnstown, Pennsylvania
Books about Pennsylvania
Books about floods | The Johnstown Flood (book) | [
"Engineering"
] | 189 | [
"History books about civil engineering in the United States",
"Civil engineering"
] |
58,320,168 | https://en.wikipedia.org/wiki/Novartis%20Prizes%20for%20Immunology | The Novartis Prizes for Immunology were established in 1990 by Sandoz to honour outstanding research in immunology, and expanded to their current form in 1992. Prizes for basic and clinical immunology are awarded every 3 years. A special prize was awarded in 2004.
Sandoz Prize for Immunology
1990 Max Cooper, Jacques Miller
Novartis Prize for Basic Immunology
2016 John Kappler, Philippa Marrack, Harald von Boehmer
2013 ,
2010
2007 Fred Alt, Klaus Rajewsky,
2004 Ralph Steinman
2001 Klas Kärre, ,
1998 Tak Mak
1995 Melvin Cohn, , Avrion Mitchison, David Talmage
1992 Jack Strominger
Novartis Prize for Clinical Immunology
2016 Zelig Eshhar, Carl June, Steven Rosenberg
2013 James Allison
2010 Charles Dinarello, Jürg Tschopp
2007 John Schiller, Doug Lowy, Ian Frazer
2004 Hugh McDevitt
2001 Alain Fischer
1998 Barry Bloom, George Bellamy Mackaness, Andrew McMichael
1995 Robert Schwartz, Thierry Boon
1992 Tadamitsu Kishimoto, Toshio Hirano
Special Novartis Prize for Immunology
2004 Leonard Herzenberg
See also
List of medicine awards
Source
References
Medicine awards
Novartis | Novartis Prizes for Immunology | [
"Technology"
] | 261 | [
"Science and technology awards",
"Medicine awards"
] |
64,998,578 | https://en.wikipedia.org/wiki/Allison%20Glazebrook | Allison Glazebrook (born 1966) is Professor of Greek Social and Cultural History, Gender and Sexuality, and Greek Oratory at Brock University. She was President of the Classical Association of Canada 2018–20.
Education and early career
Glazebrook undertook her BA at the University of Alberta before completing her MA at Queen's University at Kingston and her PhD at the University at Buffalo. Glazebrook taught at Stanford University before joining Brock University in 2003.
Work
Glazebrook's work focuses on Greek social history, working in particular on sexuality and gender. She is well known for her work on prostitutes in Athens and commented in 2019 that: "In part, my work is a reaction to scholarship that idealizes the ancient hetaira, and attempts to look at how prostitution affected the lives of women across ancient Athenian society." Glazebrook was the 2019 Visiting Speaker for the Western Tour (Manitoba, Alberta and British Columbia) of the Classical Association of Canada.
The Canadian Embassy in Athens invited Glazebrook to deliver three lectures on working women in ancient Athens in celebration of International Women's Day 2019.
From 2018 to 2020 Glazebrook was the President of the Classical Association of Canada, and now serves as Past President (2020-2022).
Select publications
(2021) Sexual Labor in the Athenian Courts, University of Texas Press
“Female Sexual Agency and an Enslaved “Olynthian”: Demosthenes 19.196-8” in Slavery and Sexuality in Classical Antiquity. eds. D. Kamen and C.W. Marshall (2021) University of Wisconsin Press. 141-58.
ed. with Christina Vester (2017) Themes in Greek Society and Culture: An Introduction to Ancient Greece (New York: Oxford University Press) ; second edition (2022)
ed. with Barbara Tsakirgis (2016) Houses of Ill Repute: The Archaeology of Brothels, Houses, and Taverns in the Greek World (Philadelphia: University of Pennsylvania Press)
"Prostitutes, Plonk, and Play: Female Banqueters on a Red-figure Psykter from the Hermitage" Classical World Volume 105, Number 4, Summer 2012 pp. 497–524
ed. with Madeleine M. Henry (2011) Greek Prostitutes in the Ancient Mediterranean, 800 BCE to 200 CE (Wisconsin studies in classics. Madison: University of Wisconsin Press)
"Prostituting Female Kin (Plut. Sol. 23.1-2)" Dike 8 pp. 33–53
References
External links
Staff page for Allison Glazebrook at Brock University
Allison Glazebrook on WorldCat
Interview with Allison Glazebrook about Classics and Women's Studies at Brock University
1966 births
Living people
Canadian classical scholars
Historians of sexuality
University of Alberta alumni
Queen's University at Kingston alumni
University at Buffalo alumni
Stanford University faculty
Academic staff of Brock University | Allison Glazebrook | [
"Biology"
] | 573 | [
"Behavior",
"Sexuality",
"Historians of sexuality"
] |
64,998,690 | https://en.wikipedia.org/wiki/Timeless%20universe | The timeless universe is the philosophical and ontological view that time and associated ideas are human illusions caused by our ordering of observable phenomena. Unlike most variants of presentism and eternalism, the timeless universe entirely rejects the notion of the reality of any time, arguing that it is exclusively a human illusion, and since the universe can know no time, no dimension of time can be permitted in any theoretical explanation of parts of the observable universe. All purported measurements of time must hence according to this view be correlation measurements between movements, as stated by physicist Ernst Mach in 1883:It is utterly beyond our power to measure the changes of things by time. Quite the contrary, time is an abstraction at which we arrive by means of the changes of things; made because we are not restricted to any one definite measure, all being interconnected.In a timeless universe the cosmos in its broadest definition is eternal, without beginning or end, and all physical processes operate within a timeless framework. Since fundamental problems related to time, such as the Arrow of time and time travel, are still among the great unsolved problems of physics, discussions of timeless universes revolve around proposed solutions to these fundamental problems and paradoxa, and the related fundamental problems of philosophy and science.
History
The first person in recorded history to contemplate a timeless universe was the Ancient Greek philosopher Antiphon, who in the 5th century B.C. held that time was a man-made measure, rather than a real thing or substance. The same opinion was held by another Ancient Greek philosopher in the 2nd century B.C., Kritolaos.
In the 2400 years since Antiphon, many different theories of possible timeless universes have been advanced, seeking to explain in whole or in part phenomena otherwise associated with or requiring the existence of time. Thinkers who have examined possible mechanisms responsible for such phenomena in a timeless universe include physicists such as Ernst Mach, Albert Einstein, Kurt Gödel and Carlo Rovelli, and timeless universes have been contemplated in works dedicated specifically to the subject by physicists such as John McTaggart, Julian Barbour and others.
Research indicates that concepts of time are not universally known to humanity since the advent of behavioral modernity, but were developed by some cultures at some unknown point along the trajectory of the development of early human society. Indigenous tribes have been studied in Amazonas and elsewhere that were found by researchers not to have any developed concept of time at all.
Ernst Mach and Albert Einstein
The fundamental 1883 statement above was outlined by Ernst Mach in his book "The Science of Mechanics" and with him the idea of a timeless universe first came to prominence as a serious scientific idea. The particular passage quoted was singled out by Albert Einstein in his 1916 obituary for Mach, in which Einstein also described the great influence the Machian corpus had exerted and continued to exert upon generations of physicists:I believe that even those who consider themselves opponents of Mach are hardly aware of how much of Mach's way of thinking they imbibed, so to speak, with their mother's milk.Einstein opens the obituary in the Physikalische Zeitschrift with a firm rejection of those of his contemporary colleagues who view the epistemological inquiries of Mach as being work of lesser importance, and then opens the obituary proper with the central question which according to him ought to passionately interest and concern any disciple of science, such as himself:What objective can and will that science achieve to which I have devoted myself? To what extent are its general results "true"? What is essential and what is only dependent on the accidents of development?Einstein then proceeds to the central and largest part of his obituary, stating the importance of Mach and his work as follows:The importance of such minds, like Mach, certainly lies not only therein, that they satisfy certain philosophical requirements of the age, which by the average inveterate specialist might be characterized as unnecessary luxury. Concepts which have proven useful in the ordering of things, through ourselves easily rise to such authority, that we forget that their origin is earthly - and accept them as unalterable/absolute facts. They are then established as "Logical necessities", "givens a priori", et cetera. The path of scientific progress is oft made inaccessible for generations through such errors. Hence it is certainly no frivolous activity, when we exercise ourselves in the analysis of these long-established concepts; in the analysis and demonstration of the circumstances upon which their justification and utility depend, even as they have emerged from the realm of experience and observed phenomena. In such exercise their overly large authority is broken: If they are unable to properly legitimize themselves, they are eliminated; if their application to a corresponding object in reality was sloppy, they are corrected; and they are replaced by others if it proves possible to adopt some new system, the which we may for some reasons prefer.
Such analyses are mostly perceived by the expert scientific specialist as superfluous, stilted, at times even ridiculous. The situation changes however, when one of the casually employed terms is replaced by a sharper more accurate one, because the development of a particular science-branch commands it: Then energic protest and lamentations are voiced by those guilty of sloppy procedure with their own terms, fearing for their most holy possessions. In this howling the voices of other philosophers chime in who think themselves unable to do without yonder term, because they had so lined it up within their little treasure-trove of the "absolute", the "a priori", et cetera, that they had proclaimed it an irrevocable fundamental principle.
The reader already conjectured that I am here particularly alluding to certain concepts of space and time and mechanics, which have been subjected to a modification through the theory of relativity. No one can take it away from the epistemologists that they paved the way here; at least in my own case I know that I have been propelled immensely, directly and indirectly, especially by Hume and Mach. I ask the reader to take into his hand the work of Mach: "The Science of Mechanics", and to contemplate his observations contained in its second chapter under parts VI. and VII. ("Newton's views of time, space, and motion." and "Discussion of Newton's view of time.")
Here we find thoughts masterfully presented, which as of yet have not at all become the common property of physicists. These parts are also especially intriguing for the reason that they grow directly out of Newtonian passages, quoted verbatim. I provide here a selection of the choicest morsels:Newton: "Absolute, true, and mathematical time, of itself, and by its own nature, flows uniformly on, without regard to anything external. It is also called duration. Relative, apparent, and common time, is some sensible and external measure of absolute time (duration), estimated by the motions of bodies, whether accurate or inequable, and is commonly employed in of true time; as an hour, a day, a month, a year..."
Mach: "... When we say a ThingA changes with time, we mean simply that the conditions that determine a ThingA depend on the conditions that determine another ThingB. The vibrations of a pendulum take place in time when its excursion depends on the position of the earth. Since, however, in the observation of the pendulum, we are not under the necessity of taking into account its dependence on the position of the earth, but may compare it with any other thing (the conditions of which of course also depend on the position of the earth), the illusory notion easily arises that all the things with which we compare it are unessential. (....) It is utterly beyond our power to measure the changes of things by time. Quite the contrary, time is an abstraction, at which we arrive by means of the changes of things; made because we are not restricted to any one definite measure, all being interconnected."These quoted lines show that Mach had clearly recognized the weak sides of classical mechanics, and was not far removed from demanding a general theory of relativity, and this already half a century ago! It is not improbable that Mach should have himself discovered the theory of relativity, if the question of the constancy of the speed of light had pre-occupied the community of physicists when he still had a fresh and youthful mind.
Einstein thus hails Mach as one of the great scientists of the era, and within his obituary gives the above passage dealing with the non-existence of time as evidence for why Mach was such a great physicist.
Kurt Gödel and Albert Einstein
Though the influence of Mach upon Einstein here described by the latter was certainly the most pronounced in the first four decades of his life, it is true that the warmth of Einstein's admiration for Mach cooled considerably after 1921 due to the posthumous publication of a text penned by Mach shortly before the latter's death disavowing any support for the theory of relativity. It must have disappointed Einstein, since we can see from partially extant friendly correspondence between the two that Mach had initially responded positively to the theory of relativity, much to the delight of Einstein. Einstein would later come to view Mach's ideas upon a number of subjects with increasing skepticism, but he never ceased to mention how Mach's work had influenced him and continued to discuss Machian problems and concepts with his close friends and colleagues.
One of these friends was Kurt Gödel, who in his works contemplated and examined universes both with and without concepts of time, the natures of which continued to be the subject of long discussions between himself and Einstein. Although in 1949 Gödel postulated a theorem that stated: "In any universe described by the theory of relativity, time cannot exist", it is important to stress that Gödel was considering many different universes employing for their theoretical constitutions many different theoretical conceptions of time. It was his endeavour to reconcile the paradoxa of time and timelessness with relativity theory upon a sound epistemological footing. Hence when Gödel is popularly known for proposing "his" universe in which time-travel is a possibility, it is in reality a gross overreduction and oversimplification of his work.
Calendars in timeless universes
In a universe where time does not exist, the measure of time is spoken of only as existing within the sphere of man-made society and its sciences. The regular motions of the sun, earth and moon are real, and the shadows they produce can hence be measured and artificially quantified into days, months and years, and subdivided using other movements for measurement into increasingly small subdivisions. This is done for convenience in human societies for purposes of measurement or comparative analysis in history or other sciences.
It is therefore still possible in a timeless universe to speak of a date in time, such as the Battle of Marathon in 490 B.C., as long as such time is clearly separated from physics, and confined to the sphere of man-made historical science and its conventions. That is, when we understand that the year is a measure for revolutions of a planet around the sun, and that our planet was measured by historians as having completed some 2510 revolutions since that event occurred, which we may read out from our catalogues that fix events to observations of physical revolutions. No real time is measured, rather observations of changes in seasons and nights and days are recorded by historians.
References
Ontology
Time | Timeless universe | [
"Physics",
"Mathematics"
] | 2,359 | [
"Physical quantities",
"Time",
"Quantity",
"Spacetime",
"Wikipedia categories named after physical quantities"
] |
64,998,709 | https://en.wikipedia.org/wiki/Laucysteinamide%20A | Laucysteinamide A (LcA) is a marine natural product isolated from a cyanobacterium, Caldora penicillata.
It is structurally related to other marine cyanobacterial metabolites such as somocystinamide A and curacin A, which have inspired extensive investigations into their use as a lead for anticancer therapies. Its biological activity profile has not been fully evaluated due to decomposition of the natural sample. However, it has shown moderate cytotoxicity against H460 human lung cancer cells.
In order to examine the possibility that LcA's true bioactivity was diminished by solubility issues, Taylor et al. chemically synthesized LcA. This synthetic sample was incorporated into an emulsifier PEG400 and tested for its cytotoxicity against H460 cells. This sample did not show any more activity than the natural sample, implying that LcA only has moderate cytotoxicity. In addition, simple enamide analogs showed no activity. This work implies that the exceptional antiproliferative activity of somocystinamide A arises from the dimeric nature of its structure and not from the enamide moiety.
See also
Caldoramide
References
Natural products
Thiazolines | Laucysteinamide A | [
"Chemistry"
] | 268 | [
"Natural products",
"Medicinal chemistry"
] |
65,001,360 | https://en.wikipedia.org/wiki/Ofqual%20exam%20results%20algorithm | In 2020, Ofqual, the regulator of qualifications, exams and tests in England, produced a grades standardisation algorithm to combat grade inflation and moderate the teacher-predicted grades for A level and GCSE qualifications in that year, after examinations were cancelled as part of the response to the COVID-19 pandemic.
History
In late March 2020, Gavin Williamson, the secretary of state for education in Boris Johnson's Conservative government, instructed the head of Ofqual, Sally Collier, to "ensure, as far as is possible, that qualification standards are maintained and the distribution of grades follows a similar profile to that in previous years". On 31 March, he issued a ministerial direction under the Children and Learning Act 2009.
Then, in August, 82% of 'A level' grades were computed using an algorithm devised by Ofqual. More than 4.6 million GCSEs in England – about 97% of the total – were assigned solely by the algorithm. Teacher rankings were taken into consideration, but not the teacher-assessed grades submitted by schools and colleges.
On 25 August, Collier, who oversaw the development of Williamson's algorithm calculation, resigned from the post of chief regulator of Ofqual following mounting pressure.
Vocational qualifications
The algorithm was not applied to vocational and technical qualifications (VTQs), such as BTECs, which are assessed on coursework or as short modules are completed, and in some cases adapted assessments were held. Nevertheless, because of the high level of grade inflation resulting from Ofqual's decision not to apply the algorithm to A levels and GCSEs, Pearson Edexcel, the BTEC examiner, decided to cancel the release of BTEC results on 19 August, the day before they were due to be released, to allow them to be re-moderated in line with Ofqual's grade inflation.
The algorithm
Ofqual's Direct Centre Performance model is based on the record of each centre (school or college) in the subject being assessed. Details of the algorithm were not released until after the results of its first use in August 2020, and then only in part.
{| border="1" cellpadding="5" cellspacing="0"
|
Synopsis
The examination centre provided a list of teacher predicted grades, called 'centre assessed grades' (CAGs)
The students were listed in rank order with no ties.
For large cohorts (over 15)
With exams with a large cohort; the previous results of the centre were consulted. For each of the three previous years, the number of students getting each grade (A* to U) is noted. A percentage average is taken.
This distribution is then applied to the current years students-irrespective of their individual CAG.
A further standardisation adjustment could be made on the basis of previous personal historic data: at A level this could be a GCSE result, at GCSE this could be a Key Stage 2 SAT.
For small cohorts, and minority interest exams (under 15).
The individual CAG is used unchanged
|-
|
The formulas
for large schools with
for small schools with
The variables
is the number of pupils in the subject being assessed
is a specific grade
indicates the school
is the historical grade distribution of grade at the school (centre) over the last three years, 2017-19.
is the predicted grade distribution based on the class’s prior attainment at GCSEs. A class with mostly 9s (the top grade) at GCSE will get a lot of predicted A*s; a class with mostly 1s at GCSEs will get a lot of predicted Us.
is the predicted grade distribution of the previous years, based on their GCSEs. You need to know that because, if previous years were predicted to do poorly and did well, then this year might do the same.
is the fraction of pupils in the class where historical data is available. If you can perfectly track down every GCSE result, then it is 1; if you cannot track down any, it is 0.
CAG is the centre assessed grade.
is the result, which is the grade distribution for each grade at each school .
|}
Schools were not only asked to make a fair and objective judgement of the grade they believed a student would have achieved, but also to rank the students within each grade. This was because the statistical standardisation process required more granular information than the grade alone. Some examining boards issued guidance on the process of forming the judgement to be used within centres, where several teachers taught a subject. This was to be submitted 29 May 2020.
For A-level students, their school had already included a predicted grade as part of the UCAS university application reference. This was submitted by 15 January (15 October 2019 for Oxbridge and medicine) and had been shared with the students. This UCAS predicted grade is not the same as the Ofqual predicted grade.
The normal way to test a predictive algorithm is to run it against the previous year's data: this was not possible as the teacher rank order was not collected in previous years. Instead, tests used the rank order that had emerged from the 2019 final results.
Effects of the algorithm
The A-level grades were announced in England, Wales and Northern Ireland on 13 August 2020. Nearly 36% were lower than teachers' assessments (the CAG) and 3% were down two grades.
Side-effects of the algorithm
Students at small schools or taking minority subjects, such as are offered at small private schools (which are also more likely to have fewer students even in popular subjects), could see their grades being higher than their teacher predictions, especially when falling into the small class/minority interest bracket. Such students traditionally have a narrower range of marks, the weaker students having been invited to leave. Students at large state schools, sixth-form colleges and FE colleges who have open access policies and historically have educated BAME students or vulnerable students saw their results plummet, in order to fit the historic distribution curve.
Students found the system unfair, and pressure was applied on Williamson to explain the results and to reverse his decision to use the algorithm that he had commissioned and Ofqual had implemented. On 12 August Williamson announced 'a triple lock' that let students appeal the result using an undefined valid mock result. But on 15 August, the advice was published with eight conditions set which differed from the minister's statement. Hours after the announcement, Ofqual suspended the system. On 17 August, Ofqual accepted that students should be awarded the CAG grade, instead of the grade predicted by the algorithm.
UCAS said on 19 August that 15,000 pupils were rejected by their first-choice university on the algorithm-generated grades. After the Ofqual decision to use unmoderated teacher predictions, many affected students had grades to meet their offer, and reapplied. 90% of them said they aimed to study at top-tier universities. The effect was that top-tier universities appeared to have a capacity problem.
The Royal Statistical Society said they had offered to help with the construction of the algorithm, but withdrew that offer when they saw the nature of the non-disclosure agreement they would have been required to sign. Ofqual was not prepared to discuss it and delayed replying by 55 days.
Legal opinion
Lord Falconer, a former attorney general, opined that three laws had been broken, and gave an example of where Ofqual had ignored a direct instruction of the Secretary of State for Education.
Falconer said the formula for standardising grades was in breach of the overarching objectives under which Ofqual was established by the Apprenticeships, Skills, Children and Learning Act 2009. The objectives require that the grading system gives a reliable indication of the knowledge, skills and understanding of the student, and that it allows for reliable comparisons to be made with students taking exams graded by other boards and to be made with students who took comparable exams in previous years.
The Labour Party suggested that the process was unlawful in that the students were given no appeal mechanism, stating: "There will be a mass of discriminatory impacts by operating the process on the basis of reflecting the previous years' results from their institutions", and "It is bound to disadvantage a whole range of groups with protected characteristics, in breach of a range of anti-discrimination legislation."
See also
2020 United Kingdom school exam grading controversy
References
External links
Requirements for the calculation of results in summer 2020 – Ofqual, 7 July 2020, updated 20 August
Student guide to post-16 qualification results: summer 2020 – Ofqual, 27 July 2020, updated 19 August
Taking exams during the coronavirus (COVID-19) outbreak – guidance from the Department for Education, published 20 March 2020, updated 27 August
Higher Education Policy Institute algorithm discussion, May 2020
Education Committee Oral evidence: The Impact of Covid-19 on education and children’s services, HC 254 Wednesday 2 September 2020
2020 in England
School examinations
Government by algorithm | Ofqual exam results algorithm | [
"Engineering"
] | 1,823 | [
"Government by algorithm",
"Automation"
] |
65,002,898 | https://en.wikipedia.org/wiki/Graves%27s%20emergent%20cyclical%20levels%20of%20existence | Graves's emergent cyclical levels of existence (E-C theory or ECLET) is a theory of adult human development constructed from experimental data by Union College professor of psychology Clare W. Graves. It produces an open-ended series of levels, and has been used as a basis for Spiral Dynamics and other managerial and philosophical systems.
Names
Graves used a variety of names for his theory during his lifetime, ranging from the generic Levels of Human Existence in his earlier work to lengthy names such as Emergent Cyclical, Phenomenological, Existential Double-Helix Levels of Existence Conception of Adult Human Behavior (1978) and Emergent Cyclical Double-Helix Model of the Adult Bio-Pyscho-Social Behaviour (1981).
In his posthumously published book, The Never Ending Quest, Graves titled the chapter introducing the theory "The Emergent Cyclical Model," and used the phrases "emergent cyclical conception" ("E-C conception") and "emergent cyclical theory" ("E-C theory") repeatedly as short names throughout the subsequent chapter on verifying his work.
However, "levels of existence" is the more commonly known part of the phrase, and was used in the title of the peer-reviewed 1970 article in the Journal of Humanistic Psychology, the single such academic psychology publication Graves made during his lifetime (although he also presented at academic conferences).
Graves himself considered the levels to be artifacts of the theory, therefore this article adopts the following conventions:
emergent cyclical theory (E-C theory) is used for the theory itself
levels of existence refers to the open-ended set of levels generated by the theory
Gravesian theory, Gravesian thought, or ECLET is used when such precision is not needed, or when there is need to discuss the body of work as a whole
Typographically, this article adopts the letter pair formatting chosen for The Never Ending Quest, which places the letters directly adjacent to each other (AN) rather than hyphenated (A-N). This is the form used in the manuscript abandoned in 1977. Graves used both hyphenated and unhyphenated forms, both before and after abandoning his manuscript. In contrast, in the same source "E-C" for "emergent cyclical" is always hyphenated.
Motivation and experimental design
Graves began his work in response to questions from his students regarding which of various conflicting psychological theories was correct. Rather than construct a hypothesis about how the conflicting systems could be resolved, Graves posed several open-ended questions and looked to see what patterns would emerge from his data. While not typical at the time, these approaches would later become known as grounded theory and inductive thematic analysis.
Graves settled on the following questions to frame his experiments:
What will be the nature and character of conceptions of psychological maturity, in the biologically mature human being, produced by biologically mature humans who are intelligent but relatively unsophisticated in psychological knowledge in general, and theory of personality in particular?
What will happen to a person's characterization of mature human behavior when s/he is confronted with the criticism of his/her point of view by peers who have also developed their own conception of psychologically mature behavior?
What will happen to a person's conception of mature human behavior when confronted with the task of comparing and contrasting his/her conception of psychologically mature human personality to those conceptions which have been developed by authorities in the field?
Into what categories and into how many categories, if any, will the conceptions of mature human personality produced by intelligent, biologically mature humans fall?
If the conceptions are classifiable, how do they compare structurally and how do they compare functionally?
If the conceptions are classifiable, how do the people who fall into classes compare behaviorally as observed in quasi-experimental situations and in every day life?
If the conceptions are classifiable, how do the people who fall into one class compare to people who fall into other classes on standardized psychological instruments?
These questions led him to design a four-phase experiment, in which collected pertinent data from his psychology students and others. His initial research, conducted between 1952 and 1959, involved a diverse group of around 1,065 men and women aged 18 to 61. Supplemental studies were carried out over the next twelve years.
Phase one: Essays on personal conceptions of the mature adult human
Students in Graves's class on "Normal Psychology" were assigned to develop their own personal conception of the psychologically mature adult human. These students included full-time male undergraduates, coed graduate students in teacher education and industrial management, and coed night school students. The students were given four weeks to produce the essay, during which the class covered relevant topics around the nature of personality and relevant human behavior for developing such a conception.
Graves's students were not aware of the research project, and were told that the papers would be graded on:
Breadth of coverage of human behavior.
Concurrence with established psychological fact.
The internal consistency of the conception.
The applicability of the conception.
Next, the students spent four weeks in small groups where each student presented their conception to the group and received criticism, after which they turned in a defense of their existing conception, or a modified conception. This step demonstrated the reaction of students to peer criticism. Finally, after another four weeks of small group study of existing conceptions of mature personality in academic psychological literature, the students once again turned in a defense or modification of their conception. This step demonstrated the reaction of students to being confronted by authority. Graves observed the students in their small group work, without their knowledge as logistics allowed, and interviewed each student after the final defense or revision was turned in.
Phase two: Classification of the essays
Each year, Graves recruited seven to nine new judges who knew nothing of the project, and instructed them as follows:
Take these conceptions of mature personality, study them, then sort them into the fewest possible categories if you find them to be classifiable. Do not force any into categories. If some do not fit any category you decide upon, just place them into an unclassifiable group.
Each judge first produced their own classification, and then the judges produced a single classification by unanimous agreement. Essays for which no unanimous classification could be determined were added to the unclassifiable group.
Phase three: Observation of behaviors of groups of people with similar conceptions
Graves also taught classes in Organizational/Industrial, Experimental, and Abnormal Psychology, and most of his students from the Phase One studies took one of those classes from him the semester after taking Normal Psychology. These classes were structured such that students were organized into groups which, unknown to them, each contained students with the same classification of mature personality. Students who had not participated in Phase One were grouped together, providing what Graves called a "moderate control" effect. Students in the Organizational and Experimental Psychology classes were given specially designed problems to solve, while those in the Abnormal Psychology class were given many standard psychological tests as part of that class's normal approach. Graves studied the groups through one-way mirrors, gathering data on how they organized themselves, interacted with each other, solved problems, and performed on standard tests.
Phase four: Making sense of the data through research
From 1960 until his retirement in the late 1970s, Graves researched other work in order to make sense of confusing aspects of his data. Since many adult humans do not take psychology classes (the source of his data), including those from cultures who do not participate in western educational systems, this phase also included research on how such adults might fit with Graves's collected data.
Development of the theory
Graves's analysis of the data collected and researched through the experiments described above became the basis for emergent cyclical (E-C) theory.
Graves theorized that in response to the interaction of external conditions with internal neurological systems, humans develop new bio-psycho-social coping systems to solve existential problems and cope with their worlds. These coping systems are dependent on evolving human culture and individual development, and they are manifested at the individual, societal, and species levels. While there is an ordered progression of stages, later stages are not presented as "better" in the sense of moral superiority. Rather, each level is best suited to the existential problems that caused it to emerge.
E-C theory produces an open-ended system of levels, which set Graves's work apart from many of his contemporaries, such as Abraham Maslow, who sought a final, perfectible state of human development.
Both progression and regression through the levels are possible in response to environmental conditions.
The emergent cyclical double-helix
Emergent cyclical theory is more broad than just the well-known set of levels of existence, and Graves considered the levels themselves to simply be artifacts of the theory. E-C theory holds that new bio-psycho-social coping systems emerge within humans in response to the interplay of external life conditions or existential problems with internal neurobiology. It is this interaction, which cycles between what Graves referred to as "express self" and "sacrifice self" systems, which is the core of the theory
Graves identified the existential problems / life conditions with letters in the first half of the alphabet (A, B, C, D, E, F...), and the emergent coping systems with letters in the second half (N, O, P, Q, R, S...). Each system emerges in response to the corresponding existential problems. (N in response to A, O in response to B, etc.) Color codes, which are common in later systems built on E-C theory, are not something that Graves ever used.
When parallel conditions and systems are paired (AN, BO, CP, DQ, ER, FS...), they describe a level of existence. In these states, the active neuronal system is the one most suited to solving the existential problems that are present in their environment. It is also possible to have non-parallel situations, such as a person in an environment with E level problems who has developed the Q neuronal system but not yet the R. This person will often find the world confusing and stressful. On the other hand, a person who is centralized at FS but finds themself in an environment of primarily E problems will be frustrated for other reasons, such as everyone around them seeming to focus on the "wrong" problems and solutions.
Old systems remain available even after new systems are developed, and the level at which a person is centralized can move forwards or backwards. A person centralized at ER who feels the need for more community and spirit can, if conditions are right, move up to FS. Or they might shift back to the familiar DQ at which they were centralized in the past. For most people, multiple systems will be available, although one may dominate.
The six upon six hypothesis
For most of Graves's original period of research, GT was the latest state to appear. Near the end, a small number of subjects expressing GT in his study shifted to a new state, HU. This emergence, seven or so years into his experiment, of a rare new system is what prompted Graves to view the set of states as open-ended, with no final, ultimate state existing.
Additionally, Graves noted a remarkable similarity between the HU and BO systems, leading him to re-evaluate GT, finding it to have similarities with AN. From this observation, he hypothesized that there are six fundamental coping systems, AN through FS. Beyond FS the cycle repeats with additional neurobiological systems adding much more development on the fundamental states, with the result that "motivations are recapitulated in a much vaster conceptual context." In recognition of this, he began using primes to mark the higher-order systems, renaming GT to A'N' and HU to B'O'. While Graves viewed this hypothesis as unproven, he felt that the data demanded its consideration.
Conditions for change
A key part of E-C theory is the change process by which a person moves from one level of existence to the next. There are six conditions for change in this process:
Potential
Solutions of existing problems
Feeling of dissonance
Gaining of insights
Removal of barriers
Opportunity to consolidate
Consider a person centralized at ER, who is facing new problems of the F sort, which will require a change to being centralized at FS. The person must have the potential to change, including openness to change. They must have solved the problems of their current level (the E problems), in order to have available energy and resources to focus on the next set of problems (the F problems). They must have felt the dissonance that comes from their currently dominant R system failing to solve the F problems. They must gain insight into how the R system is failing them, and how the S system will help. Any barriers to making this change must be removed or overcome, and once newly centralized at FS, the person needs a supportive environment while they come to fully understand how to successfully exist at this new level.
The levels of existence
While the levels are the most well-known part of E-C theory, Graves emphasized that they are theoretical constructs rather than realities, calling them "the base points from which the living, behaving human varies." In contrast to the values focus of the later Spiral Dynamics formulation, Graves focused on the motivations that he saw as underlying each level, with alternating "express" and "sacrifice" themes.
Unless otherwise noted in the column heading or individual cell, the information in the following table is adapted from the first few pages of each level's description in The Never Ending Quest.
Verification of the theory
Graves compared his conception of adult development with those of many of the leading thinkers of his time, concluding that most were compatible with his view, but often had gaps compared to his set of levels, or only addressed part of the range. In a lengthy examination of Graves's work,
Nicholas Reitter considers that in reaching these conclusions "Graves appears in his relative isolation to have convinced himself of greater scientific support than can reasonably be claimed for a particular developmental view such as his, however great its appeal and other merits." However, in his review of The Never Ending Quest, Allan Combs agrees that Graves's theory shows "broad similarities to the highly researched stage the- ories of Lawrence Kohlberg (1981) and Carol Gilligan (1993), as well as Robert Kegan (1994) and others."
Graves also validated aspects of his change process against other researchers who had used recognized scales for measuring a person's psychological state.
Using the theory with individuals
Graves demonstrated that individuals react more quickly to words associated with their value system than with those associated with others. More recent research has built on this to show differences in neurological activation among those operating from individualistic vs collectivistic stages. While some academic research has been done on assessing the presence of bio-psycho-social coping systems in individuals, Graves did not publish any such tools. He noted:
Those who have tried to develop instruments have based them on what people think, do or believe, which is not the proper base for assessment devices. They should be based not on what the person thinks but how s/he thinks, not on what people do or what they believe but how they do what they do, and how they believe that which they do believe.
In the time since Graves's death, assessments have been produced by practitioners of Spiral Dynamics, which is built on E-C theory.
While some have treated Graves's levels as a "simplistic categorization tool," Graves noted that even a person centralized at a particular level drew only roughly 50% on that level, 25% on the level before it, and 25% on the level after. In his original data, Graves found that about 60% of his subjects were centralized around one level, while 40% were more mixed. A person might operate from different levels at home vs at work or in other contexts, and might change to be centralized at either a later or earlier level depending on their environment.
Criticism
Graves's primary data set, which produced the CP-B'O' levels, consisted entirely of students taking his "Normal Psychology" course, raising concerns of sampling bias and lack of diverse life perspectives. During the 1970s, Graves collected additional data from prison populations, industrial workers, and other educational institutions, although it is not documented how this compared to his original methodology, or the degree to which it impacted the theory. Furthermore, the BO and AN levels were the result of research in anthropological literature and therefore not the product of the same methodology as the other levels.
Validating Graves's results is viewed as challenging as his raw data was thrown out towards the end of his life, with only collated results retained. Graves's results as presented in his posthumous writing have been criticized as too vague to support the universality of his conclusions.
Graves's approach of using his students as subjects without their knowledge would be considered ethically dubious today.
Graves's assertions regarding neurobiology lack direct evidence, and are in need of validation by experts in that field.
In his review of The Never Ending Quest, Allan Combs notes that the timeline of the emergence of the levels, while "at home with modern scholarship on the history of consciousness," is speculative beyond what Graves's data could support.
While some variations of Spiral Dynamics have been criticized for producing cult-like communities of practice, several people who level that criticism note that it does not apply to Graves's work itself. In an examination of Graves's work in the June 2018 issue of the Journal of Conscious Evolution, however, Nicholas Reitter connects this phenomenon with Graves having not fully published his ideas during his lifetime. He observes that Graves's ideas are "more often cited, used in conversation, or otherwise recognized tangentially, than they are examined straightforwardly and thus subjected to deliberate acceptance, refutation, or criticism," and that furthermore by "leaving his legacy in not-quite-finished form, and in cultivating followers who have elaborated his ideas leaving them essentially unquestioned, [Graves] appears to have succeeded in leaving us a provocative and important theory, while so far avoiding anything like a debate about its merits."
Influence
E-C theory has primarily been influential in the field of business management, having first been published to a broad audience in the Harvard Business Review after Graves encountered difficulty finding a psychology theory-oriented journal interested in publishing his work. Other researchers in this field built on Graves's work during his lifetime, and his work continues to be cited in journals regarding business-related topics such as
change management,
cross-cultural management,
marketing,
sustainability,
hiring of workers with disabilities,
and the neurology of decision-making. Additionally, Graves's work has formed the basis of several non-academic books on business strategy and change.
Gravesian theory has also been applied in the field of education.
While sometimes referenced in the context of academic publications on psychology,
or cited alongside other developmental psychologists such as Jane Loevinger or Lawrence Kohlberg,
Graves's ideas are not broadly influential in mainstream psychology or philosophy academia.
However, Graves is neither entirely unknown nor entirely dismissed among mainstream developmental psychologists. For example, Loevinger cited his observations on relative developmental levels of managers and employees while of defending her concept of ego development as the "master trait" in response to a competing proposal of neuroticism or conscientiousness occupying that role.
Graves's work influenced Ken Wilber's integral theory starting no later than 1995, prior to the publication of Spiral Dynamics. By way of Spiral Dynamics, this influence became increasingly prominent during the 2000s, although subsequent changes by Wilber have diverged from Graves in some respects such as truncating the second "tier" of stages to two, contradicting the "six upon six" hypothesis.
E-C theory has also influenced, again by way of Spiral Dynamics, developmental metamodernism.
Notes
References
(an early version of the transcription is available online)
Developmental psychology | Graves's emergent cyclical levels of existence | [
"Biology"
] | 4,137 | [
"Behavioural sciences",
"Behavior",
"Developmental psychology"
] |
65,003,632 | https://en.wikipedia.org/wiki/Brain%20balls | In Irish history and legend, brain balls () are small stone-like balls claimed to have been made from the heads or brains of enemies. No examples that modern analysis confirms as human have survived.
Description
In literature and legend
In Geoffrey Keating's 17th century Foras Feasa ar Éirinn (or 'History of Ireland') in 'An Account of the Death of Connor, King of Ulster' he records the background of the tradition, and a Christianised tale relating to it. According to Keating it was the custom during the period described in the Ulster Cycle for a victorious champion to take the brains of a defeated adversary, and make a ball of them, by mixing it with lime, followed by drying in the sun - such a ball was displayed at important events. In the story told by Keating, two fools in the court of king Conchobar mac Nessa (Connor son of Ness) decided to steal such a brain ball, being from the head of Mesgegra, former king of Leinster - having stolen it the fools then began to play with it. Whilst doing so they were discovered by Cet mac Mágach of the kingdom of Connacht, he then took the brain ball from the fools. Later the provinces of Connacht and Ulster became at war, and Cet used the ball as a sling stone, wounding Connor grievously in the head - this began the fulfillment of a prophecy that Mesgegra would be revenged on Ulster after his death - King Connor's doctors advised that extreme stress of exertion might open the ball's wound and kill him, and so he lived carefully for seven years. However one day an eclipse occurred and Connor sought his druid on its cause - he was informed that the cause was the murder of Jesus by the Jews - Connor became incensed by this news, and this caused the wound to re-open, bringing about his death. Keating notes that Connor died before the death of Jesus, and gives the explanation that the druid must have prophesied Jesus's death.
Archaeological evidence
In Irish dolmens balls have been fairly common finds, often found in the structure's floor or lower level detritus, and often associated with bones - materials identified as forming the balls include marble (thought to be a slingshot); ironstone ; calcium carbonate; porphyry; and syenite - with sizes recorded were from approximately . Some of the balls found inside dolmen cairns in the region of Slieve na Calliagh in the County of Meath were claimed by E.A. Conwell to be 'brain balls' as described in historical sources and legend.
Amongst stone balls discovered in the tombs in Meath Conwell also uncovered some which were initially soft, when discovered in the earth, but hardened on drying out after which it became possible to excavate them. He identified several in two tombs as being 'brain balls'. Of these several had been worn down to a smaller size, but he identified one as being better preserved.
William Frederick Wakeman also found objects he ascribed to be 'brain balls' in a tomb in Old Connacht, Bray. Wakemen submitted a sample for analysis - the ball was approximately diameter, light yellowish, and friable, containing some harder material. The harder pieces were thought to be splinters of long bones and or vegetable charcoal on inspection under a microscope. The main body of the ball was made of amorphous cement, which gave an analysis of primarily calcium carbonate, plus calcium phosphate plus traces of iron. The analysis concluded that they were man made, but too soft to be used as weapons, and furthermore did not resemble 'brain balls' made from lime with varying proportions of sheep's brain and or powdered bone. Wakeman came to the conclusion that these balls were coprolites.
Similar balls in Irish legends
Sling shot balls made for a special purpose were known as caer-clis ('feat ball') or uball-clis ('feat apple') - they were made in a special way or with certain ingredients. An example is the tathlum made by the Tuatha Dé Danann from the "blood of toads, bears, and vipers, mixed up with sea-sand and hardened" - this ball was used by Lugh to kill Balor.
See also
Carved stone balls
References
Sources
, 3 vols. , (Reissued: )
Archaeology of Ireland
Archaeological artefact types
Brain
Spherical objects | Brain balls | [
"Physics"
] | 907 | [
"Spherical objects",
"Physical objects",
"Matter"
] |
65,005,031 | https://en.wikipedia.org/wiki/Glyceryl%20octyl%20ascorbic%20acid | Glyceryl octyl ascorbic acid (GO-VC) is an amphipathic derivative of vitamin C consisting of two ether linkages: a 1-octyl at position 2 and a glycerin at position 3. The chemical name is 2-glyceryl-3-octyl ascorbic acid. The isomer in which these two groups are swapped (2-octyl-3-glyceryl ascorbic acid, OG-VC) is also known.
It is considered as a new stable amphipathic in the field of aesthetic medicine.
Overview
Vitamin C is rapidly converted to ascorbic acid radicals by UV rays, which causes cytotoxicity and sunburn, but GO-VC improves the stability of conventional vitamin C derivatives, and thus eliminates the problems of these prooxidants. Water-soluble vitamin C derivatives, such as sodium ascorbyl phosphate (APS), which have been used since the 1990s, have a problem of drying the skin in order to the sebum suppression effect. On the other hand, GO-VC has a high moisturizing power due to the binding of glycerin and can prevent the dryness of the skin. In addition, GO-VC has a sterilizing activity of octanol, so it has a sterilizing activity against many bacteria.
GO-VC is also used for wound healing and wrinkle prevention because it has a proliferative effect on fibroblasts and a promoting effect on type I collagen production. GO-VC has a stronger melanin production inhibitory effect than arbutin, which is used as a whitening agent, and it was confirmed in clinical trials that even low concentrations of 0.01 to 0.1% (by weight) are effective against acne redness and pigmentation.
The water-soluble vitamin C derivatives such as ascorbic acid 2-glucoside and APPS (trisodium ascorbyl palmitate) can not add to water-soluble polymer gels commonly used in cosmetics such as carboxy vinyl polymer and sodium polyacrylate. This is because the viscosity changes, causing precipitation. On the other hand, GO-VC can be dispersed in water-soluble polymer gel transparently and uniformly or can be stably dissolved for a long time.
The fat-soluble vitamin C derivatives such as ascorbyl tetrahexyl decanoate (VC-IP) are almost insoluble in water, making it difficult to mix in water-soluble formulations such as lotions without the use of surfactants. Fat-soluble vitamin C derivatives causes lipid oxidation problems when lipids are released, and the color of the formulation tends to change. GO-VC can solve these problems almost completely.
GO-VC is well absorbed percutaneously due to its amphiphilic nature, and because it is negatively charged rather than completely non-ionic, it can facilitate percutaneous absorption with an iontophoresis device. In addition, GO-VC is amphipathic but does not have a lipid group, so there are few skin toxicity problems due to lipid peroxidation, and it does not have the sticky feeling of conventional vitamin C derivatives and has a good feel.
Stability
When the aqueous solution containing vitamin C and GO-VC was stored at 50 °C for 90 days, the vitamin C residual amount decreased to less than 30% in 30 days, whereas the residual amount of GO-VC was 90% or more. Moreover, after 90 days, 80% or more of GO-VC was confirmed to remain.
It is considered that these high stability are due to the two most reactive hydroxyl groups of vitamin C being capped by glycerin and octanol at the same time. Because the viscosity is stable in the preparation containing GO-VC and the polymer gel too, and it can be kept in a transparent state for a long period of time. Therefore, GO-VC can be added to many preparations such as lotions, creams, serums and gels.
Acne
It was reported that GO-VC is effective against post-inflammatory hyperpigmentation (PIH), post-inflammatory erythema (PIE), and atrophic scar (AS), which are important complications in acne. It applied a complex vitamin C derivative lotion containing GO-VC to each of 10 patients with acne twice on the right side twice a day for 3 months, and confirmed the left side without application and its effect. It was reported that there was a marked improvement in PIH, PIE, and AS on the only right side applying lotion containing GO-VC after 3 months.
Pigmentation
Many phenolic compounds, which are conventional whitening agents, react with tyrosinase to induce melanocyte-specific cytotoxicity, and thus there was a risk of developing vitiligo. GO-VC reduced the intracellular melanin content of B16 melanoma cells. GO-VC's pigmentation inhibitory mechanism is shown to act through a novel melanogenesis inhibitory system that does not depend on tyrosinase activity inhibition, indicating that it is a safe and effective pigmentation inhibitor with low risk of vitiligo. GO-VC showed a remarkable effect in an actual pigmentation suppression clinical study, and a gel preparation containing 0.1% GO-VC was applied twice a day in the morning and evening on the entire face after 13 female subjects aged 39.8 years on average. As a result of a 1-5 month study, GO-VC significantly improved post-inflammatory pigmentation. It is reported that GO-VC also showed a clear improvement in pigmentation caused by metal allergy, which was not very effective when applied with hydroquinone.
Skin pore related diseases
Since conventional water-soluble vitamin C does not easily penetrate the skin barrier, an amphipathic vitamin C derivative was developed to improve this. However, since lipids such as palmitic acid were chemical modified to vitamin C derivatives in the past, exposure to ultraviolet light generated free fatty acids, raising concerns about lipid peroxidation. It was thought that GO-VC could avoid the problem of lipid peroxidation because GO-VC is amphipathic with octanol instead of lipid. The effect of 0.05% gel of GO-VC was investigated on skin pore related diseases. As a result, it was confirmed that there were no side effects and the number of abnormal pores decreased to 70% or less within 1 to 2 months after application.
References
Organic acids
3-Hydroxypropenals
Glycerol ethers
Lactones | Glyceryl octyl ascorbic acid | [
"Chemistry"
] | 1,394 | [
"Organic acids",
"Acids",
"Organic compounds"
] |
65,006,488 | https://en.wikipedia.org/wiki/Ship%20abandonment | Ship abandonment can occur for a variety of reasons and cannot be defined in a single way. Most cases are of ships abandoned by owners because of economic hardship or economic issues, for example because it becomes less expensive than continuing to operate, paying debts, port fees, crew wages, etc. The abandoned ships may remain, often with their crews as hostages, in a port for extended periods, with the crew unpaid, and possibly dangerous cargo on board. In many cases, the crew cannot leave without losing their right to be paid. Abandonment has been described as a "cancer" of the shipping industry.
If cases go to court, the sale of the vessel can be ordered, but this can take many months. Jurisdiction is often unclear because many abandoned vessels sailed under "flags of convenience" (open registries). An amendment to the Maritime Labour Convention made it easier for unpaid crew to be paid via insurance.
In 2020 the International Maritime Organization (IMO) database listed 438 ships worldwide, with 5,767 crew members, abandoned since 2004; not all cases are referred to the IMO, so the actual number is larger, but unknown. In 2020, by August 470 seafarers on 31 vessels had been abandoned. The Abandoned Seafarer Map project, an independent research tool, seeks to document all known cases of abandonment.
Seafarers' problems, including abandonment, in the Arab world and Iran were sufficiently severe for the International Transport Workers' Federation (ITF) to set up a network for the region; its coordinator said "The flood of calls to ITF in the Arab region has never stopped. Since we created the network and seafarers [became] aware of us, the numbers of calls are going up and up". the network was dealing with 15 cases of abandonment.
Notable cases
A notorious case was the 2013 abandonment of MV Rhosus in Beirut, Lebanon, the unloading and storing for years of its explosive cargo, and the ensuing catastrophic explosion on 4 August 2020. A previous crew had mutinied due to unpaid wages. When the ship docked in Beirut, it was arrested for non-payment of port dues, and the owner did not respond to the captain's communications. The captain and three crew members remained on the ship, unpaid, for a year, relying on the port agent for food and water to keep them alive. The explosive cargo was unloaded as collateral for the unpaid debts, then left for years in a warehouse until it exploded.
Celanova, a broken-down Spanish-flagged liquefied gas carrier with 15 crew trapped in Manila, Philippines for months in 2020. The ITF and the International Labour Organization intervened to allow the crew to land, and the ship was sold, presumably to pay creditors.
References
Ships | Ship abandonment | [
"Physics"
] | 560 | [
"Physical systems",
"Transport",
"Transport stubs"
] |
65,006,943 | https://en.wikipedia.org/wiki/Rib%20%28nautical%29 | On a vessel's hull, a rib is a lateral structural member which runs between gunwales and sprouts from the keel. They are called "ribs" because they resemble the human rib. The ship's outer planking and inner sheathing are attached to the ribs. For ships that are too large for a rib to be made out of a single piece of wood, the ribs are made of multiple sections called futtocks that are scarfed together. The ancient writers Polybius and Plato held that, since the ribs of a ship were the most important part of the ship's framework, then if the ribs were new, then the ship as a whole was new. Iron was first used in shipbuilding to make the ribs and frames, with wood sheathing attached to them, but this proved inadequate compared to replacing the wood sheathing with iron plates.
See also
Frame (nautical)
References
Nautical terminology
Shipbuilding | Rib (nautical) | [
"Engineering"
] | 187 | [
"Shipbuilding",
"Marine engineering"
] |
65,008,055 | https://en.wikipedia.org/wiki/Primary%20cell%20culture | Primary cell culture is the ex vivo culture of cells freshly obtained from a multicellular organism, as opposed to the culture of immortalized cell lines. In general, primary cell cultures are considered more representative of in vivo tissues than cell lines, and this is recognized legally in some countries such as the UK (Human Tissue Act 2004). However, primary cells require adequate substrate and nutrient conditions to thrive and after a certain number of divisions they acquire a senescent phenotype, leading to irreversible cell cycle arrest. The generation of cell lines stems from these two reasons. Primary cells can become immortalized either spontaneously (e.g. HeLa cells) or by genetic modification (e.g. HEK cells), at which point they become cell lines which can be subcultured indefinitely.
Because of their requirements for viability, primary cell cultures did not become widespread until the 2000s. These cultures present several advantages over cell lines, including a better representation of the cellular heterogeneity of tissues, a more faithful transcriptomic and proteomic profile (especially when cultured in 3D) and more realistic functional responses, including drug responses. In contrast, immortalized cell lines are known to become homogeneous through the natural selection of specific subpopulations, to undergo genetic drift and to acquire genetic aberrations. In many cases, cell lines have been misidentified, contaminated with other cells or infected with Mycoplasma, small intracellular bacteria that went undetected for decades.
When whole or partial tissues are isolated and maintained ex vivo, the procedure is termed primary tissue culture. More specific terms include organotypic culture, tissue slices and explants.
Neuronal primary cell cultures are cells collected from the brain of an organism. For example they can be used when examining substances effect on cell viability, which can further on be potential treatments for brain deficits.
Monolayer cultures
Monolayer cultures refer to cell cultures where cells are grown in a single, flat layer on the surface of a culture dish or substrate. In a monolayer culture, cells adhere to the substrate and spread out in a two-dimensional arrangement. This type of cell culture is commonly used in laboratory settings for various purposes, including research, drug testing, and biotechnology.
Key features of monolayer cultures include:
Two-Dimensional Growth: Cells in monolayer cultures grow in a single plane, adhering to the surface of the culture vessel. This flat arrangement allows for easy observation and manipulation of individual cells.
Adherence to Substrate: The cells attach to the surface of the culture dish or flask, and their growth and behavior can be influenced by the characteristics of the substrate.on the other words In cell culture, adherence to substrate describes a cell's capacity to adhere to a surface and proliferate. Many elements, including surface energy, substrate topography, and roughness, mediate the process of cell attachment. The study of artificial polymer surfaces with varying chemical, topological, and mechanical cues that regulate cell activities has focused attention on the interaction between external surfaces and cells. In a study that was published in the journal RSC Advances in 2021, the impact of roughness and surface energy on cell adhesion and growth was examined. The most advantageous circumstances for effective cell adhesion, development, and proliferation were discovered by the study to be moderate surface energy and intermediate roughness ratio.
Cell Proliferation: Cells in monolayer cultures can undergo cell division and proliferation. This feature is crucial for experimental studies and the production of a larger number of cells for subsequent analyses.
Observation and Imaging: The two-dimensional nature of monolayer cultures makes it convenient for microscopic observation and imaging. Researchers can easily visualize the cells, study their morphology, and monitor changes over time.
Cell Differentiation: Depending on the cell type and culture conditions, monolayer cultures can be used to induce cell differentiation. This is particularly important in studying developmental processes and tissue-specific functions.
Monolayer cultures for personalized therapy
The endocrine cancer with the highest incidence is thyroid cancer (TC). Differentiated thyroid cells (DTC) that originate from follicular thyroid cells account for over 90% of total thyroid cells (TC). Papillary TC (PTC), follicular TC (FTC), and Hürthle cell TC are examples of DTC. One percent of TC is anaplastic TC (ATC), which accounts for 15–40% of TC deaths.
Mortality is one of the biggest obstacles to current treatment techniques against aggressive DTC or ATC. These strategies are not entirely effective against these conditions. Recent years have seen advancements in our knowledge of the molecular and genetic underpinnings of TC development as well as the introduction of novel medications, such as tyrosine kinase inhibitors (TKIs), which target the oncogenic or signaling kinases linked to cellular proliferation.
Preclinical models have made use of thyroid cell lines that were isolated from tumor cells and selected for their high rate of proliferation in vitro. As a result of their adaptation to in vitro growth circumstances, these cells actually lose the distinctive characteristics of the original tumor. Because of these factors, there are significant restrictions on the usage of these cell lines. More recently, monolayer cultures of human primary cells have been created, and their biological behavior has been studied. Furthermore, whereas human primary cell cultures may now be created from samples of fine-needle aspiration cytology from aggressive dedifferentiated DTC or ATC, primary TC cells were previously only obtained by surgical biopsies. Without the use of useless medications, testing several TKIs in vitro on individual patients can aid in the development of novel, individualized treatments.
Limitations of monolayer culture and motivations:
Scientists are investigating novel models that can more accurately mimic the structure and function of human organs because to the limitations of monolayer culture settings. Protocol improvements in recent times have led to the creation of three-dimensional (3D) organ-like architectures known as "organoids," which are able to exhibit properties of their corresponding real organs, such as morphological features, functional activities, and individual responses to particular pathogens.
Cell culture protocol
For in vitro investigations to be conducted correctly, the cell culture protocol for a particular cell line must be optimized. The best culture conditions for different cell lines can differ significantly due to the heterogeneity of germ cell malignancies.
See also
3D cell culture
Induced pluripotent stem cell
Patient-derived xenograft
Stem cell laws
References
Cell culture | Primary cell culture | [
"Biology"
] | 1,329 | [
"Model organisms",
"Cell culture"
] |
65,008,732 | https://en.wikipedia.org/wiki/Brooklyn%20Bridge%20%28software%29 | The Brooklyn Bridge from White Crane Systems was a data transfer enabler. Although it came with some hardware, it was the software which was the basis of the product. It also could transform the data's format.
Overview
The New York Times described its category as being among "communications packages used to transfer files." In an era of 300 baud, Brooklyn Bridge operated at "115,200 baud" so that a transfer which "at 300 baud took 4 minutes and 36 seconds" only needed
5 seconds. Unlike some communications packages, this one retains the original version-date, so as not to alarm people
when they seem to have what looks like an update, when it's not.
Description
Once the software is installed, users comfortable with typing the word "COPY" can do so as readily as they sneakernet. An earlier review described it as "less cumbersome than conventional communications software" The use of neither specialized hardware nor specialized software is ideal in an era when this can be done using online or other "outside" services.
See also
BLAST (protocol)
Kermit (protocol)
Zamzar
References
Communication software
Computer data
Data management
History of software | Brooklyn Bridge (software) | [
"Technology"
] | 239 | [
"Computer data",
"Data management",
"History of software",
"Data",
"Computing stubs",
"History of computing"
] |
65,009,955 | https://en.wikipedia.org/wiki/Itai%20Yanai | Itai Yanai (born 6 February 1975) is an American-Israeli biomedical scientist and Founding Director of the Institute for Computational Medicine at the NYU Grossman School of Medicine. He is also a professor in the Department of Biochemistry and Molecular Pharmacology at NYU.
Early life and education
Yanai was born in Haifa, Israel, and moved with his family to Boston in his early teens, when his father Moshe Yanai was appointed Chief Engineer at EMC. He graduated from Boston University in 1998 with degrees in computer engineering and philosophy, both summa cum laude. In 2002 he became the first person in the nation to receive a Ph.D. in, what was at the time, the fledgling field of Bioinformatics. After several years at the Weizmann Institute and Harvard University, he returned to Israel in 2008 as a faculty member at the Technion-Israel Institute of Technology. He moved to the United States in 2016, when he assumed his current position.
Research
Yanai has published extensively in bioinformatics and theory. He has also done seminal experimental research in cell biology.
In 2016 Yanai co-authored a popular book for the general public.
Together with Martin J. Lercher, Yanai has written a series of editorials on the creative side of the scientific process, which he called "Night Science" in reference to François Jacob. He also co-hosts a popular podcast with the same name.
References
1975 births
Living people
21st-century American academics
21st-century American biologists
Academic staff of Technion – Israel Institute of Technology
Academics from Boston
Boston University alumni
Educators from Haifa
Harvard University people
New York University Grossman School of Medicine faculty
Scientists from Boston
Scientists from Haifa | Itai Yanai | [
"Chemistry"
] | 347 | [
"Biochemistry stubs",
"Biochemists",
"Biochemist stubs"
] |
65,011,422 | https://en.wikipedia.org/wiki/Mackerelmedia%20Fish | Mackerelmedia Fish is a 2020 experimental ARG-like browser-based video game developed by Nathalie Lawhead. The game explores themes and settings related to 1990s and early 2000s Internet culture (its name being a parody of Macromedia Flash), especially the loss of digital history through deprecations and data decay. Some of the game is directly implemented on a website's open .htaccess directories, while other portions of it take the user through other previous art projects by Lawhead, such as an application titled Electric Zine Maker.
Development
According to the developer's blog, much of the game was built with Tumult Hype, an HTML5 development application. Lawhead mentioned wanting to have some sort of fictional context for Electric Zine Maker, and created Mackerelmedia Fish as a tie-in to that project as well as future ones. They also mentioned wanting to create an interactive project that made use of open directories for a long time. The project's code has been released on GitHub.
Reception
The game was named one of the Games of the Month of April 2020 by itch.io staff writers, who called it the "perfect entry point for alternate reality games". Writing for Rock, Paper, Shotgun, Lauren Morton praised the game for its 'clever oddity', calling it a "portal back to my childhood when the internet was, if not weirder than now, differently weird". Writing for The Verge, Adi Robertson referred to it as "a strangely adorable ode to dying websites". PC Gamer and The Verge both compared the game favourably to Hypnospace Outlaw.
References
External links
Official website
Official page on itch.io
2020 video games
2020s interactive fiction
Adventure games
Browser games
Alternate reality games
Single-player online games
Internet-based works
Parody video games
Video games developed in the United States
Mass media about Internet culture | Mackerelmedia Fish | [
"Technology"
] | 391 | [
"Multimedia",
"Internet-based works"
] |
59,941,185 | https://en.wikipedia.org/wiki/Hill%20Top%20Colliery | The Hill Top Colliery in Sharneyford between Bacup and Todmorden was, until 2014, the last coal mine still in operation in Lancashire.
Foundation
The Hill Top Colliery was opened in 1948. In 1948, the National Coal Board built two drifts leading downwards into the average thick Union coal seam. Under the National Coal Board it employed from 1950 to 1965 on average 101 men underground and 9 above. At its peak there worked about 200 miners.
Drifts
The Intake Drift with a 1 to 1½ (66%) grade was 78 meters long, while the lesser steep Return Drift was 339 meters long at a 1 to 4 (25%) grade. The rails of the plateways consisted of L-shaped steel profiles with a gauge of probably . The cart of the winch-operated inclinehad flangeless metal disc wheels and were also used for passenger transport, because of the low height of the drifts. They were pushed in the plane by hand and driven on downhill slopes with winches. Some of the numerous cart were probably acquired second-hand from the disused Old Meadows Colliery.
Employees
The nearby Moorfield Colliery in Accrington was closed shortly after the nationalization in 1947, after which many of the formerly employed miners worked in the Hill Top Colliery. In less than 20 years they have produced 400 tons of coal per week before the mighty Union seam was exhausted in 1966. The coal had a relatively high sulfur content and was therefore sold mainly to the chemical industry in Widnes.
Drainage
Powerful pumps, running day and night, were supplied with electrical power via an overhead line belonging to the mine. They pumped just over 1,000 liters (250 gallons) per minute out of the Hill Top Colliery and across the watershed of the Heald Moor into the Irwell Valley and not via the Greens Clough into the Yorkshire Calder, which would have been the far cheaper alternative.
Temporary closure and reopening
In 1966, the mine was closed after the coal deposits seemed to be exhausted. The Grimebridge Colliery Co Ltd, led by miners William (Billy) Clayton and his business partner Rodney Mitchall, obtained a license to exploit Hill Top Colliery and opened the pit again. In the summer of 1997 two drifts were dug into the large seam between the previous tunnels and an open pit mine on the Heald Moor. The planning permission for the construction of the two new drifts was granted in August 1989. However, the start of construction was delayed, so that in 1997 an application for renewal of this permit was made and approved. In September 2005, a permit was granted for the continuation of mining until August 2011.
Coal deposits
The coal reserves, extend underground over a working area of about 9 hectares. In 1997, the coal authority granted a license to mine 110,000 tonnes of coal. Although about 150,000 tonnes of coal were still available, only less than 50 tonnes were mined in 2003 due to staff shortages. Four miners, who worked only in the morning in the mine, promoted until October 2011, only 2900 tonnes of coal.
Change of ownership
Billy Clayton died unexpectedly of a heart attack on 16 May 2008, when he brought his grandson back from school. Then his equally named son Billy Clayton son took over the operation of the mine until it was closed in 2014.
Health and safety
In December 2016, the state Health and Safety Executive issued a prohibition notice to warn about the risk of water leakage and an improvement notice suggestion regarding the requirement for regular expert assessments of the compressor.
Coal balls
In Lancashire, especially in the Burnley area, peat concretions are known as coal balls or colloquially as Burnley bobbers. They are particularly common in the seams of the Upper Foot Mine and Lower Mountain Mine in East Lancashire but also in the mines in Todmorden Moor on the eastern edge of this coal field. Due to their hardness, they often caused damage to the mining equipment, as well as the picks, drums and cutting jibs in the coal mines in North East Lancashire. In the mines of Todmorden Moor the coal balls were common. Some were collected by the locals from the waste heaps because of the petrifactions, others are still there.
References
External links
The End of an Era: Hilltop Colliery – Bacup, 1997–2014, The Last Coal Mine in Lancashire, b3tarev3, 15. April 2014
Hilltop Colliery – Lancashire: A rare glimpse into Lancashire's last working coal mine.
The Geograph: Hill Top Colliery
Lancashire Colliers (Grimebridge) Granada Video
Coal mines in England
Mining railways
Lancashire
Plateway | Hill Top Colliery | [
"Engineering"
] | 922 | [
"Mining equipment",
"Mining railways"
] |
59,941,251 | https://en.wikipedia.org/wiki/Cysteine-rich%20protein | Cysteine-rich proteins (CRP, cysteine-rich peptide or disulphide-rich peptide) are small proteins that contain a large number of cysteines. These cysteines either cross-link to form disulphide bonds, or bind metal ions by chelation, stabilising the protein's tertiary structure. CRPs include a highly conserved secretion peptide signal at the N-terminus and a cysteine-rich region at the C-terminus.
Structure
Disulphides
In an oxidising environment cysteines cross-link to form disulphide bonds. CRPs that form these typically have an even number of cysteines.
Metal binding
Cysteines can coordinate one or more metal ions by forming a chelation complex around them.
Functions in plants
CRPs are numerous in plants, with 756 CRP-encoding genes in the Arabidopsis thaliana genome. Several CRPs bind known receptors, but most CRP signaling mechanisms and protein interactions are uncharacterized. Characterized CRPs function as short-range intercellular signals during processes such as plant defense, bacterial symbiosis, stomatal patterning, fertilization, vegetative tissue development, and seed development.
Many CRPs function in plant defense. Defensins, a major class of CRP with an eight-cysteine motif forming four disulfide bridges, are involved in pathogen response. Other putative antimicrobial CRPs include lipid transfer proteins, thionins, knottins, heveins, and snakins. Additionally, some CRPs have allergenic, ɑ-amylase inhibitory, or protease inhibitory functions that deter herbivores.
In plant reproduction, CRPs are involved in pollen tube growth and guidance and early embryo patterning, in addition to other functions. Among those involved in pollen tube attraction are the LUREs, a group of ovular pollen-tube attractants in Arabidopsis thaliana and Torenia fournieri that preferentially attract conspecific pollen, and STIG1, a CRP expressed in the stigma of Solanum lycopersicum that interacts with the pollen-specific receptor PRK2. In early embryo development, CRPs such as ESF1 are necessary for suspensor development and normal seed morphology.
References
Proteins
Sulfides
Protein classification
Cysteine-rich proteins | Cysteine-rich protein | [
"Chemistry",
"Biology"
] | 504 | [
"Biomolecules by chemical classification",
"Protein classification",
"Cysteine-rich proteins",
"Molecular biology",
"Proteins"
] |
59,941,326 | https://en.wikipedia.org/wiki/Small%20protein | Small proteins are a diverse fold class of proteins (usually <100 amino acids long). Their tertiary structure is usually maintained by disulphide bridges, metal ligands, and or cofactors such as heme. Some small proteins serve important regulatory functions by direct interaction with certain enzymes and are therefore also an interesting tool for biotechnological applications in microorganisms.
Identification of small proteins
The size of small proteins has limited their identification and characterization for a long time. However, the various examples of functionality have led to the development of methods for their identification.
For larger ORFs, computational identification is based solely on their long uninterrupted coding potential. Computational searches for small proteins take into account multiple parameters, such as the presence of a ribosome binding site and amino acid conservation. RNA sequencing or mass spectrometric data sets available are also incorporated into computational predictions.
A method extensively used for the identification of small proteins is ribosome profiling (Ribo-seq or ribosome footprinting). Ribosome profiling uses next generation sequencing and targets only mRNA sequences protected by the ribosomes. Binding of a ribosome on an mRNA suggests that the transcript is being actively translated, allowing for the identification even of very small ORFs.
Mass spectrometry is the best method thus far for identifying small proteins, but their sizes again pose a barrier. However, several adjustments are possible to perform to improve detection and data quality.
See also
Cysteine-rich protein
Intrinsically disordered proteins
Metal-binding protein
Micropeptide
References
Proteins | Small protein | [
"Chemistry"
] | 325 | [
"Biomolecules by chemical classification",
"Protein stubs",
"Biochemistry stubs",
"Molecular biology",
"Proteins"
] |
59,941,638 | https://en.wikipedia.org/wiki/Metal-binding%20protein | Metal-binding proteins are proteins or protein domains that chelate a metal ion.
Binding of metal ions via chelation is usually achieved via histidines or cysteines. In some cases this is a necessary part of their folding and maintenance of a tertiary structure. Alternatively, a metal-binding protein may maintain its structure without the metal (apo form) and bind it as a ligand (e.g. as part of metal homeostasis). In other cases a coordinated metal cofactor is used in the active site of an enzyme to assist catalysis.
Histidine-rich metal-binding proteins
Poly-histidine tags (of six or more consecutive His residues) are utilized for protein purification by binding to columns with nickel or cobalt, with micromolar affinity. Natural poly-histidine peptides, found in the venom of the viper Atheris squamigera have been shown to bind Zn(2+), Ni(2+) and Cu(2+) and affect the function of venom metalloproteases. Furthermore, histidine-rich low-complexity regions are found in metal-binding and especially nickel-cobalt binding proteins. These histidine-rich low complexity regions have an average length of 36 residues, of which 53% histidine, 23% aspartate, 9% glutamate. Intriguingly, structured domains with metal binding properties also have very similar frequencies of these amino acids that are involved in the coordination of the metal. Accordingly, it has been hypothesized that these metal-binding structured domains could have originated and evolved/optimized from metal-binding low-complexity protein regions of similar amino acid content.
References
Proteins | Metal-binding protein | [
"Chemistry"
] | 356 | [
"Biomolecules by chemical classification",
"Proteins",
"Molecular biology"
] |
59,942,748 | https://en.wikipedia.org/wiki/C2H6N2O2 | {{DISPLAYTITLE:C2H6N2O2}}
The molecular formula C2H6N2O2 (molar mass: 90.08 g/mol) may refer to:
Methylazoxymethanol
Dimethylnitramine
Methylolurea
Methyl carbazate
2-Nitroethanamine
N-Nitroethanamine | C2H6N2O2 | [
"Chemistry"
] | 79 | [
"Isomerism",
"Set index articles on molecular formulas"
] |
59,945,568 | https://en.wikipedia.org/wiki/BitSight | BitSight Technologies, Inc. is a cybersecurity ratings company that analyzes companies, government agencies, and educational institutions. It is based in Back Bay, Boston. Security ratings that are delivered by BitSight are used by banks and insurance companies among other organizations.
The company rates more than 200,000 organizations with respect to their cybersecurity.
History
BitSight was founded in 2011 by Nagarjuna Venna and Stephen Boyer and currently has both United States-based and international employees. In 2016, BitSight raised US$40 million in funding in the month of September.
In 2014, BitSight acquired AnubisNetworks, a Portugal-based cybersecurity firm that tracks real-time data threats.
By September 2016, BitSight had raised $40 million in a Series C round led by GGV Capital, with participation from Flybridge Capital Partners, Globespan Capital Partners, Menlo Ventures, Shaun McConnon, and the VC divisions of Comcast Ventures, Liberty Global Ventures, and Singtel Innov8.
Shaun McConnon stepped down as the CEO of BitSight in July 2017 but remains the executive chairman of the board. The CEO position was filled by Tom Turner in 2017, and then by Stephen Harvey in 2020.
In June 2018, BitSight closed $60 million in Series D funding, bringing the company's total funding to $155 million. BitSight's Series D financing was led by Warburg Pincus, with participation from existing investors Menlo Ventures, GGV Capital and Singtel Innov8.
In 2018, the company was located in Cambridge but purchased property in order to shift to Back Bay, where BitSight is currently located. Forbes has estimated BitSight's revenue as being $100 million as of 2018.
In 2021, BitSight acquired VisibleRisk, a cyber risk assessment startup company and received a $250 million investment from Moody's Corporation.
In 2023, BitSight partnered with Schneider Electric to develop a new way to quantify operational technology risk.
In 2024, Bitsight acquired Cybersixgill, a real-time cyber threat intelligence company.
Services
Organizations purchase BitSight's services in order to understand "security risks associated with sharing sensitive data with business partners." As of 2018, BitSight serves clients, including Lowe's, AIG, and Safeway.
BitSight assembles models that produce company ratings, which are based on a scale that enables insurers to rule on the ability of businesses to receive coverage. It produces ratings for 200,000 organizations as of 2020.
With respect to its services, Amy Feldman of Forbes wrote that "Customers pay on a subscription basis with annual fees ranging from a few thousand dollars to analyze a single company to more than $1 million to review thousands of suppliers." Similar to a credit score, BitSight's ratings range from 250 to 900.
References
External links
Back Bay, Boston
Companies based in Boston
Computer network security
Privately held companies based in Massachusetts
2011 establishments in the United States
Warburg Pincus companies | BitSight | [
"Engineering"
] | 620 | [
"Cybersecurity engineering",
"Computer networks engineering",
"Computer network security"
] |
59,947,005 | https://en.wikipedia.org/wiki/Developable%20mechanism | Developable mechanisms are a special class of mechanisms that can be placed on developable surfaces.
Examples
Some well-known examples of developable mechanisms include the door on the Apollo Command Module and the cargo doors on the Space Shuttle. Both of these examples are single-hinge-line mechanisms. Note how in each case the joint axes are in line with the ruling lines of the surface. Images are shown on the right.
Origami uses developable surfaces because the paper can be assumed to not stretch. Action origami utilizes the movement of the origami.
Ortho-planar mechanisms are a subset of developable mechanisms where the developable surface is a plane and the links emerge out of the plane. Lamina Emergent Mechanisms are ortho-planar mechanisms (and hence also developable mechanisms) where the joints are compliant mechanisms. The same joints used to create lamina emergent mechanisms can be used to approximate developable surfaces
Advantages
Developable surfaces are easy to manufacture and are found in many applications. Developable mechanism can be embedded within these surfaces.
Developable mechanisms are deployable.
Developable mechanism stow compactly during one position of the mechanism's motion.
Mathematical Modeling
The motion of developable mechanisms can be modeled using traditional kinematics formulas. In rigid-body linkages, the shape of the rigid links does not change the motion.
References
External links
About Developable Mechanisms
Video about the applications and development of Developable Mechanisms
Mechanisms (engineering) | Developable mechanism | [
"Engineering"
] | 301 | [
"Mechanical engineering",
"Mechanisms (engineering)"
] |
59,949,490 | https://en.wikipedia.org/wiki/NGC%204093 | NGC 4093 is an elliptical galaxy located 340 million light-years away in the constellation Coma Berenices. The galaxy was discovered by astronomer Heinrich d'Arrest on May 4, 1864. NGC 4093 is a member of the NGC 4065 Group and is a radio galaxy with a two sided jet.
A rotating disk in the galaxy was detected by K. Geréb et al.
See also
List of NGC objects (4001–5000)
References
External links
4093
038323
Coma Berenices
Astronomical objects discovered in 1864
Elliptical galaxies
NGC 4065 Group
Radio galaxies
Discoveries by Heinrich Louis d'Arrest | NGC 4093 | [
"Astronomy"
] | 128 | [
"Coma Berenices",
"Constellations"
] |
59,951,498 | https://en.wikipedia.org/wiki/Valery%20E.%20Forbes | Valery E. Forbes is an American ecologist and professor specializing in environmental toxicology. Since the start of the 2022-2023 academic season, she has been the Dean of the Charles E. Schmidt College of Science at Florida Atlantic University. Her research expertise is in ecotoxicology, where she primarily studies effects of environmental stresses on organisms at different levels of biological organization.
Education
As an undergraduate student, Forbes received B. A.'s in Biology and Geology at Binghamton University in 1983. She later attended Stony Brook University, completing her M.S. in Marine Environmental Sciences in 1984, and her PhD in Coastal Oceanography in 1988.
Scientific contributions
Research in the Forbes lab is aimed at improving environmental management through increased understanding of how risks, such as exposure to toxins and temperature change, impact ecosystems. With over 350 peer reviewed publications and a google scholar citation index of 8658, Forbes is an internationally recognized expert in assessing risks to complex ecosystems through population modeling. Her expertise led to her participation of an advisory council formed to advise SETAC-Europe about using mechanistic effect models for ecological risk assessment of chemicals.
Awards and honors
Helmholtz International Fellow
Fellow of the University of Minnesota Institute of the Environment
Member of the Board of Directors, Minnesota Freshwater Society
Fulbright Scholar, Odense University, DK
Professional activities
Editorial Board, PeerJ, 2017–Present
Editorial Board, Integrated Environmental Assessment and Management, 2018–Present
Editorial Board, Human and Ecological Risk Assessment, 2005–Present
Editorial Board, Marine Environmental Research, 2000–Present
Invited Member of the Spinoza Prize Selection Committee, Netherlands Organization for Scientific Research, 2013–16
Editorial Board, Ecotoxicology and Environmental Safety, 2004-13
Director, Centre for Integrated Population Ecology, 2005–09
Danish Natural Sciences Research Council Member, 2001–07
External links
University of Minnesota lab page
European Food Safety Authority Conference Discussion 24 September 2018
Representative publications
References
Living people
American environmental scientists
Year of birth missing (living people)
American women scientists
University of Minnesota faculty
Stony Brook University alumni
Binghamton University alumni
American ecologists
American women academics
21st-century American women | Valery E. Forbes | [
"Environmental_science"
] | 424 | [
"American environmental scientists",
"Environmental scientists"
] |
59,951,553 | https://en.wikipedia.org/wiki/Edible%20vaccine | An edible vaccine is a food, typically plants, that contain vitamins, proteins or other nourishment that act as a vaccine against a certain disease. Once the plant, fruit, or plant derived product is ingested orally, it stimulates the immune system. Specifically, it stimulates both the mucosal and humoral immune systems. Edible vaccines are genetically modified crops that contain antigens for specific diseases. Edible vaccines offer many benefits over traditional vaccines, due to their lower manufacturing cost and a lack of negative side effects. However, there are limitations as edible vaccines are still new and developing. Further research will need to be done before they are ready for widespread human consumption. Edible vaccines are currently being developed for measles, cholera, foot and mouth disease, Hepatitis B and Hepatitis C.
Benefits
Edible vaccines differ from traditional vaccines in many ways and overcome many of their limitations. Traditional vaccines can be too expensive or restricted to manufacture and develop in certain countries. In contrast, edible vaccines are easy to produce, purify, sterilize, and distribute. Since they do not require more expensive manufacturing equipment, only rich soil, the cost to grow the vaccines is significantly lowered. In addition, edible vaccines do not require sterilized production facilities or the biosafety standards required to cultivate certain pathogenic agents for traditional vaccines which are expensive to implement and maintain. They are also easier and less expensive to store since they do not require strict refrigerated storage. This necessity for cold chain storage creates many issues in third world countries. The seeds from an edible vaccine plant can also be easily dehydrated and preserved for cheap and quick distribution which makes them easily accessible in times of need.
Edible vaccines also offer a profuse amount of potential health benefits that edible vaccines have over traditional vaccines. Eating a vaccine is a simpler means of administration compared to injection, making them extremely economical. This reduces the need for medical personnel and sterile injection conditions that are not always achievable in developing countries. Edible vaccines are considered a "pharmafood" which is a food source that increases health while also fighting diseases. The benefit of using plants is that plants are efficient vectors for vaccine production. Many traditional vaccines that are developed from cultured mammalian cells can lead to contamination with animal viruses. However, edible vaccines eliminate this issue because plant viruses cannot impact humans. Moreover, as a result of numerous antigens being integrated, the M-cells are randomly stimulated; leading to the possibility of second-generation vaccines.
Edible vaccines do not require subsidiary elements to stimulate an immune response like traditional vaccines. Some major concerns with traditional vaccines are potential side effects, for example, allergic reactions. Since edible vaccines lack certain toxic compounds and only contain therapeutic proteins, which are free of pathogens and toxins, the risk of potential side effects and allergic reactions are greatly reduced.
Limitations
Edible vaccines also have multiple disadvantages compared to traditional vaccines. Since edible vaccines are still in their infancy, there are still many unknowns left to discover. The adequate dosage amount and how long it lasts is still undetermined. The dosage varies due to many factors including: the plant generation, the individual plant, the protein content, the ripeness of the fruit and how much of it is eaten. The dosage also varies due to the difficulty in standardizing the concentration of the antigen in the plant tissue; it can be tedious to produce both consistently and large scale. The antigen concentration can also vary significantly between individual fruits on a plant, individual plants, and between plant generations. Low doses result in the consumption of less antibodies but a high dose results in establishing an oral and immune tolerance to the vaccine proteins. The logistics of controlling dosage, quality, and consistency still need to be determined and verified.
Since it is such a new field, the long-term effects are still unknown. Additionally, the effects and risk of using pesticides on the plants could be negative towards both the plant vaccine and the consumer. There is also the risk of transgenic escape into the surrounding environment; however, this could be reduced by regulating growing practices and locations. Many plants are not eaten raw and the cooking could weaken or destroy the proteins in the vaccine. In a study, it was found that after boiling a potato for 5 minutes, half of the vaccine survived, thus showing that not all edible vaccines have to be ingested raw if dosages account for cooking times and temperatures. There is also a concern that the gastric enzymes and the acidic environment of the stomach will break down the vaccine before it can activate an immune response. Moreover, concerns have arisen regarding the vaccine behavior being different due to the differing glycosylation pattern of plants and humans.
Production
Edible vaccines are subunit vaccines; they contain a antigen proteins for a pathogen but lack the genes for the full pathogen to form. The first steps in making an edible vaccine is the identification, isolation, and characterization of a pathogenic antigen. In order to be effective, the antigen needs to elicit a strong and specific immune response. Once the antigen is identified and isolated, the gene is cloned into a transfer vector. One of the most common transfer vectors for DNA being used for edible vaccines is Agrobacterium tumefaciens. The pathogen sequence is inserted into the transfer DNA (T-DNA) to produce the antigenic protein. It is then inserted into the genome, expressed, and inherited in a mendelian fashion, which results in the antigen being expressed in the fruit or plant. From that point forward, traditional vegetative methods and techniques are used to grow the plants and propagate the genetic line.
Techniques
The entire gene is inserted into a plant transformation vector to allow transcription or the epitope within the antigen is identified and the DNA fragment can be used to construct genes by fusion with a coat protein gene from a plant virus. Then, the recombinant virus can infect other plants. The epitope is first identified, and then, DNA fragment encoding is used to construct genes by fusion with a coat protein gene from plant virus (TMV or CMV). The transgene can be expressed either through a stable transformation system or through transient transformation system based on where the transgene has been inserted into the cell.
Stable transformation
A stable transformation involves a nuclear or plasmid integration in which permanent changes occur in the recipient cells' genes and the targeted transgene is integrated into the genome of host plant cells.
Transient transformation
A transient transformation involves a plasmid/vector system using Agrobacterium tumefaciens which integrates the exogenous genes into the T-DNA, then infects the vegetable tissue. Agrobacterium is the common technique used currently because it's a pathogenic bacterium, found in soil that naturally infects plants and transfers their genes (T-DNA) to the nucleus of the plant. A. tumefaciens is the most preferred strain because it carries tumour-inducing plasmids. The genes will be made into a neutralized Ti-plasmid and the heterologous gene is inserted to form a recombinant plasmid vector. The vector is then turned into the desired strain with the help of the virulence genes of the bacterium. It is then transferred and integrated into the genomic DNA of the host plant by non-homologous recombination at random sites. This method has a low yield and is a slow process, and it is the most effective when used with dicotyledonous plants such as, tomato, potato, and tobacco.
Bombardment method
Another technique is the microprojectile bombardment method where selected DNA sequences are processed and penetrated into the chloroplast genome. The gene containing DNA coated metal particles are fired at the plant cells using a gene gun. The plants take up the DNA, grow into new plants, then are cloned to produce large numbers of genetically identical crops. The gene transfer is independent, and it can express antigens through nuclear and chloroplast transformation.
Additional methods
There are a few other techniques that have been tested, however, the three techniques describe above are more common and practical. One of the alternative methods is nuclear transformation. This is when the desired gene is inserted into the plant nucleus through non-homologous recombination. Furthermore, electroporation has been considered, but it is not common because the cell wall has to be weakened before the pulses and DNA insertion can occur. Lastly, it is thought that molecular farming can be used so that the plants can be used as protein factories.
Immune response
After the vaccine is orally ingested, it reaches the digestive tract mucosa and stimulates the mucosal immune system. These provide the first-line of defense against attacking pathogens. The M-cells (found in Peyer's patches) in the mucous membranes of the lymphoid tissues push the antigens to the antigen presenting cells in the underlying tissues. The antigenic epitopes are then shown on the antigen presenting cells' surface and the T-cells activate the B-cells. The activated B-cells then move to the mesenteric lymph nodes where they become plasma cells and move to the mucous membrane to produce immunoglobulin A (IgA) (a type of antibody). Then the M-cells channel the antigen. As the cells go toward the lumen, the IgA combine with secretary components to make secretory IgA (sIgA). Then, the sIgA and the specific antigenic epitopes work together to eliminate the unwanted pathogen.
Research
Current research has focused on a variety of different types of plants in order to determine which is the most eligible and efficient. The plant has to be robust, nutritious, appetizing, transformable, and ideally domestic. Some examples of crops that are being tested include: corn, tomato, rice, carrots, soybeans, alfalfa, papaya, quinoa, peas, apples, algae, wheat, lettuce, potatoes, bananas, and tobacco; with the last four being the most common. When looking at which plants are the best, there are many factors that must be taken into account. From the research, scientists have started to pair crops with diseases. They believe that edible vaccines can be made for many diseases; such as, rotavirus, cholera, gastroenteritis, autoimmune disease, malaria and rabies For example, they think that booster shots can be distributed through lettuce. It is also essential to find foods that can be eaten raw because it is thought that cooking would denature the proteins. Because of this, bananas and tomatoes have become top viable options. While bananas are productionally inexpensive and native in many underdeveloped nations, tomatoes have the ability to preserve healing processes because they are immune to thermal process; this makes them great for HIV antigens. They are an ideal crop because they contain beta-amyloid. Even though crops seem optimal, it is also necessary to look at the by-products. For example, tobacco has been found to be good for recombinant protein production, it is unsuitable for vaccine production because the plant also produces toxic compounds. Additionally, potatoes have been a main focus for edible vaccines, so much so that clinical trials using potatoes has already began.
Vaccines in development
Presently, there are edible vaccines for measles, cholera, foot and mouth disease, and hepatitis B, C, & E. However, even though there are edible vaccines, they are predominately tested in the animal testing and in development phases, with some human clinical trials being conducted. As mentioned above, the human trials have revolved around potatoes. In one cholera study, adults were given transgenic potatoes with various LT-B amounts in order to see how their IgA anti-LT and IgA anti LT amounts changed. Furthermore, they are in phase II on a potato vaccine booster for hepatitis B. Hepatitis B surface antigens were expressed in the potatoes and were given to already vaccinated patients. It was then observed if an immune response occurred. 95% of the volunteers had some form of an immune response, and 62.5% showed an increase in anti-HBsAg titers. From these studies, the National Institute of Allergy and Infectious Disease has supported that edible vaccines can safely trigger an immune response, however, it is also known that they are far from being able to begin large scale human testing for autoimmunity and infectious diseases.
Animal testing
Many animal studies have already been developed. For example, experimental animals were given transgenic bananas with anti-hemagglutination specific antibodies to combat measles. It was found that the bananas did initiate an immune response. Moreover, mice trials have started as a method to treat Alzheimer's using tomatoes that have undergone agrobacterium mediated nuclear transformation. Additionally, rabbits were orally immunized with an edible vaccine for bovine pneumonic pasteurellosis, and there was a positive response. While those were two specific studies, generally speaking, research using mice models are being conducted to treat cholera and type 1 diabetes.
Availability
While the public awareness regarding edible vaccines is increasing, they are still not available for consumer use. Currently, they have only developed and started testing edible vaccines for some diseases. During three of the recent disease outbreaks around the world, edible vaccines have been developed for testing on animals but have not reached human trials. Also, it has been found that a biotechnological company has started to develop a patent and are working on beginning clinical trials for a transmissible gastroenteritis virus.
References
Vaccination | Edible vaccine | [
"Biology"
] | 2,815 | [
"Vaccination"
] |
59,953,471 | https://en.wikipedia.org/wiki/DNA-templated%20organic%20synthesis | DNA‐templated organic synthesis (DTS) is a way to control the reactivity of synthetic molecules by using nature's molarity‐based approach. Historically, DTS was used as a model of prebiotic nucleic acid replication. Now however, it is capable of translating DNA sequences into complex small‐molecule and polymer products of multistep organic synthesis.
Base Editors
The DNA base editors, developed at Harvard University under David Liu, allow altering the genomic structure of DNA. The base editors include BE3, BE4 and ABE7.
BE3 and its later version, BE4 allow to change the nucleobase C to T and nucleobase G to A. ABE7 allows to change A-T base pairs into G-C base pairs. The system works by rearranging the atoms in the target base pair and then tricking cells into fixing the other DNA strand to make the change permanent.
References
Biological engineering
Biotechnology
Genome editing
Molecular biology | DNA-templated organic synthesis | [
"Chemistry",
"Engineering",
"Biology"
] | 199 | [
"Genetics techniques",
"Biological engineering",
"Bioengineering stubs",
"Genome editing",
"Biotechnology stubs",
"Genetic engineering",
"Biotechnology",
"nan",
"Molecular biology",
"Biochemistry"
] |
59,953,630 | https://en.wikipedia.org/wiki/Wildlife%20of%20Norway | The wildlife of Norway includes the diverse flora and fauna of Norway. The habitats include high mountains, tundras, rivers, lakes, wetlands, sea coast and some lower cultivated land in the south. Mainland Norway has a long coastline, protected by skerries and much dissected by fjords, and the mostly-icebound archipelago of Svalbard lies further north. The flora is very varied and a large range of mammals, birds (many migratory), fish and invertebrate species live here, as well as a few species of reptiles and amphibians.
Geography
Mainland Norway is a mountainous, elongated country with a very long coastline. It extends from a latitude of 58°N to more than 71°N, which is north of the Arctic Circle, and there are some 50,000 smaller islands off the extremely indented coastline. The Scandinavian Mountains extend along the length of the country; the average elevation is and 32% of the mainland is located above the tree line. The mountains end abruptly on the west coast and there is little in the way of a coastal plain. Between the mountains are deep valleys, with lowland largely limited to the southeastern region of the country and the south coast. The far northeast of the country is less mountainous, with rolling hills and the Finnmarksvidda plateau.
Further north still, the archipelago of Svalbard has an arctic climate; the land surface on the three large and many smaller islands is 60% glacier ice, 30% rock and scree, and only 10% is vegetated. The island has its own distinctive flora and fauna.
Climate
The climate of much of the mainland is subarctic, with some continental climate in the southeast and some oceanic climate around the coast. Compared to other places at similar latitudes, the temperature is higher because of the warm North Atlantic Current, and the coast normally remains free of ice. The predominant winds bring relatively warm, humid air in from the Atlantic. Much precipitation falls on the western side of the mountains, with the long inland valleys being rather drier and land to the east of the mountains experiencing a rain shadow effect, with less precipitation, more sunshine and usually warmer summers. The far north and northeast of the country are drier but experience much fog and drizzle.
The climate of Svalbard is dominated by its high latitude, with the average summer temperature at and January averages at . The West Spitsbergen Current moderates Svalbard's temperatures, particularly during winter.
Flora
Vegetation zones in Norway include forests, bogs, wetlands and heaths. Boreal species are adapted to the long, cold winters but need a growing season of sufficient length and warmth. Thus typical boreal species include the Norway spruce and pine, while at higher altitudes deciduous trees like downy birch, grey alder, aspen and rowan predominate. Higher still, these give way to dwarf willows and birches above which are tundra, rock and ice. The tundra is too exposed and the climate too severe to support trees and large plants, and here grow mountain grasses and low-growing alpine plants such as mountain avens and purple saxifrage. At even higher altitudes mosses and lichens provide the chief vegetation cover.
Estimates of the total number of species in the country include 20,000 species of algae, 1,800 species of lichen, 1,050 species of mosses, 2,800 species of vascular plants, and up to 7,000 species of fungi.
In parts of the country with a more continental climate, spruce and pine are dominant and grow at higher elevations than other trees, but in other areas, mountain birch forms the tree line, at around in central southeastern Norway, descending to at the Arctic Circle and to sea level further north. At higher altitudes, the terrain is arctic tundra.
Svalbard has permafrost and tundra, with both low, middle and high Arctic vegetation. 165 species of plants have been found on the archipelago. Only those areas which defrost in the summer have vegetation cover and this accounts for about 10% of the island group.
Fauna
Excluding bacteria and viruses but including marine organisms, the total number of animal and plant species in Norway is estimated at 60,000. This includes 16,000 species of insects (probably 4,000 more species yet to be described), 450 species of birds (250 species nesting in Norway), 90 species of mammals, 45 fresh-water species of fish, 150 marine species of fish, 1,000 species of fresh-water invertebrates, and 3,500 species of marine invertebrates.
Terrestrial mammals on mainland Norway include the European hedgehog, six species of shrews and ten of bats. The European rabbit, the European hare and the mountain hare all live here as do the Eurasian beaver, the red squirrel and the brown rat as well as about fifteen species of smaller rodent. Of the ungulates, the wild boar, the muskox, the fallow deer, the red deer, the elk (N. American usage: 'moose'), the roe deer and the reindeer are found in the country.
Terrestrial carnivores include the brown bear, the Eurasian wolf, the red fox and the Arctic fox, as well as the Eurasian lynx, the European badger, the Eurasian otter, the stoat, the least weasel, the European polecat, the European pine marten and the wolverine. The coast is visited by the walrus and six species of seal, and around thirty species of whale, dolphin and porpoise are found in Norwegian waters.
Norway has a great variety of bird species utilising its many habitats, cliffs, wetlands, forests and tundra. In the summer, insects and other food sources are plentiful and the days are long, giving plenty of time for birds to forage and feed their young. This is not the case in winter when the ground is covered in snow, the wetlands in ice and the days are short, so many of the birds are migratory, usually breeding in Norway and overwintering in southern Europe or Africa.
Six terrestrial species of reptiles have been recorded in Norway: the viviparous lizard, the sand lizard, the slow worm, the European adder, the grass snake and the smooth snake, and leatherback and loggerhead sea turtles occasionally visit the coast. Amphibians are limited to the smooth newt, the great crested newt, the common toad, the common frog, the moor frog and the pool frog.
There are four terrestrial mammalian species on Svalbard, the Arctic fox, the Svalbard reindeer, the polar bear and the accidentally introduced southern vole, which is found only around Grumant. There are around eighteen species of marine mammal including whales, dolphins, seals and walruses. The rock ptarmigan is the only resident species of bird but the snow bunting and wheatear also nest on Svalbard as do the nearly thirty species of seabird that migrate here each year. Most freshwater lakes in the Svalbard archipelago are inhabited by Arctic char.
References
Norway
Biota of Norway | Wildlife of Norway | [
"Biology"
] | 1,441 | [
"Biota by country",
"Wildlife by country",
"Biota of Norway"
] |
59,956,741 | https://en.wikipedia.org/wiki/Brenda%20Ryman | Brenda Edith Ryman (6 December 1922 – 20 November 1983) was a biochemist and Mistress of Girton College, Cambridge.
Ryman was educated at Colston's Girls' School and Girton College, Cambridge. She was on the staff of the Royal Free Hospital from 1948 to 1972; Professor of Biochemistry at Charing Cross Hospital from 1972; and Mistress of Girton College, Cambridge from 1976 until her death.
References
1922 births
1983 deaths
People educated at Montpelier High School, Bristol
Physicians of the Royal Free Hospital
Physicians of Charing Cross Hospital
Alumni of Girton College, Cambridge
Mistresses of Girton College, Cambridge
Women biochemists | Brenda Ryman | [
"Chemistry"
] | 133 | [
"Biochemists",
"Women biochemists"
] |
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