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73,555,843 | https://en.wikipedia.org/wiki/Ostrich%20eggshell%20beads | Ostrich eggshell beads, considered among the earliest ornaments created by Homo sapiens, represent some of the most ancient fully manufactured beads. Archaeologists have traced their origins back to the Late Pleistocene, with evidence suggesting they were crafted as early as 75,000 years ago in Africa. Certain populations continue to produce and utilize these beads in contemporary times.
Ostrich eggshell beads likely originated from eastern Africa. They appear in the archaeological record all throughout Africa in a variety of contexts, including those of foraging, herding, and farming societies. They are particularly well-represented in the archaeological record of the Holocene, and are well-studied in eastern and southern Africa. They can be useful to archaeologists as a way to study symbolic meanings, the creation and maintenance of social identities, exchange, and can even be used to radiocarbon date sites. They also appear in the archaeological record of Asia, with some beads dating to 12,000 years old.
Manufacture
The manufacture of ostrich eggshell beads varies a bit from region to region, but generally follows similar steps. First, an ostrich egg is hit with a hammerstone, or an eggshell fragment is found. Then, bead blanks are selected from those fragments. The next two steps can be performed in either order depending on the group making the beads; either a hole is drilled in the bead's center, often with a sharp stone, piece of bone, or horn, or the process of trimming the bead is performed before the perforation. After trimming and perforation of the bead, several beads are strung together on a piece of cord. There might have been intentional burning during this process to darken the beads' color. Ethnographic and historical data in Africa indicates that these beads were manufactured by women in a time-intensive process. It may have been a seasonal process and regarded as a social event in some areas, with bead manufacturing occurring more frequently in large camps.
In southern Africa, historical ethnographic data all point to the use of iron tools for perforating the ostrich eggshell beads. Collins et al. argue that there were heat alterations to the ostrich eggshell beads found at a site called Grassridge Rockshelter in South Africa. This site showed significant signs of bead manufacture. The scholars note that grooved stone found at the site could be the tool used to finish the beads, since finishing the beads is traditionally done by using a coarse surface like the stone to grind them.
Style
The style of ostrich eggshell beads has been used in scholarship to investigate the arrival of herding in areas of southern Africa. Specifically, bead diameter is thought to play a significant part in this process, with a larger diameter associated with the spread of herding. However, in a 2019 study by Miller and Sawchuk, the diameter size of ostrich eggshell beads did not appear to change during the period of the arrival of herding in eastern Africa. However, in many contexts foragers do appear to have manufactured smaller beads compared to pastoralists.
Between the period of 50 - 33 thousand years ago, a study by Miller and Wang suggests that the style of ostrich eggshell beads was nearly identical in eastern and southern Africa, though these styles diverged in later periods. Hatton et al. suggests that larger beads might have been preferred in the northeast of southern Africa, medium-sized beads were favored in the western region of southern Africa, and the small-size in the Drakensberg.
Use as personal adornment
Archaeological data
Ostrich eggshell beads are often used as personal adornment. Though it is difficult to determine the use of these beads in the past, Collins et al. conclude that the beads with depressions could have been sewn onto clothing or bags as adornment. Another possibility is that the beads were placed on necklaces or strings as jewelry. There is also a high volume of these beads found in pillar cemetery sites around Lake Turkana, which implies that the beads were important for identity signaling. The use of beads as personal adornment does not appear to have been differentiated based on an individual's age or sex, based on the analysis of grave goods.
Tryon argues that the archaeological evidence of beads missing in some contexts where the raw material is available in eastern Africa is indicative of the use of ostrich eggshell beads as a choice to reject certain technologies because they were perceived to be contrary to the needs or norms of the society.
Ethnographic data
Data derived from studying some modern African populations suggests that these beads hold symbolic meaning as personal adornment. The ethnographic data also show that individual beads can be used as a means to display social information, such as details about group norms. In the Kalahari today, ostrich eggshell beads are used by hunter-gatherer groups to adorn jewelry, clothing, and bags. However, archaeologists practice caution when using ethnographic data to inform interpretation of the archaeological record, since cultures change over time.
Exchange
Ostrich eggshell beads found in the archaeological record were often imported from different locations. For example, ostrich eggshell beads are found in Lesotho archaeological sites, even though ostriches were not likely present in this region.
In their study of ostrich eggshell beads in southern and eastern Africa, Miller and Wang posit that since the style of the beads are so similar between the regions from the period of 50 - 33 thousand years ago, there was likely exchange going on between these two regions. They further suggest that the differences that emerged in style of the beads after this period indicate that the regional exchange network seemed to have broken down after 33 thousand years ago.
The specific exchange practice that the oldest beads were a part of was hxaro, a process in which hunter-gatherer groups from different regions exchanged these beads in the form of jewelry. In this exchange, the beads could travel several hundred kilometers. This exchange process involved both men and women.
Social networks in Southern Africa
The trade and exchange of ostrich eggshell beads might be the world's first social network. The variation in beads carry culturally and socially significant information, and the beads can be used as symbols to create and maintain connections within a society. Since the beads appear throughout southern Africa, it appears that their use as decorative ornaments were shared between different groups and peoples living in different parts of southern Africa. Jacobson suggests that social identity might have been established by the size of ostrich eggshell beads, differentiating the hunter-gatherers and the herders in an area where there would have been a lot of economic contact between the groups. In areas of hxaro exchange, the trade of ostrich eggshell beads could create friendship ties between both individuals and families, providing an important social function to the exchange. The beads could both cement and also reassert these friendship ties, in a way that advertised these bonds outwardly. This could serve as kinds of "insurance policies," ensuring help if it was ever needed, due to the beads advertising these connections. According to Mitchell, the trade also maintains and reproduces the egalitarian social values of the San people.
References
Beadwork
Jewellery components
Archaeological artefact types | Ostrich eggshell beads | [
"Technology"
] | 1,480 | [
"Jewellery components",
"Components"
] |
73,557,548 | https://en.wikipedia.org/wiki/Violence%20and%20autism | Various connections have been made between violence and autism within social narratives. According to public opinion, violent behavior is common for autistic individuals, but evidence does not support autism spectrum disorder (ASD) as a predisposition to delinquency or crime. Autistic people are likely to be victims of bullying, abuse and other violence.
Violence against autistic people
Autistic individuals are often victims of violence, including bullying, abuse, sexual assault and criminal acts. Violence can be physical or verbal, as illustrated by the frequent use of the word "autistic" as an insult. Autistic people, like many people with disabilities, are often victims of hate crimes, and many live in fear.
A 2003 study found that children diagnosed with Asperger syndrome were more likely to be victims of violence than tormentors. Violence against non-speaking autistic people is also facilitated by the fact that they are unable to talk about it and report it: in general, the more a person is considered to be "in a weak situation", or as a "severe" case, the more vulnerable they are to violence and exclusion. Dependence is an aggravating factor, especially if daily assistance is required for everyday activities such as meals and washing. The "seriousness" of the "disability" can thus be invoked to justify all types of violence, including murder.
In schools
Bullying is "the most common form of violence among children and adolescents", according to Park, et al. (2020). Autistic students are victims more often than other students; the prevalence of being victimized is higher than being a perpetrator of bullying.
In the family environment
Familial abuse against autistic children does not appear to be more frequent than familial abuse against non-autistic children.
However, cases of infanticide, usually committed by the mother of the autistic child, have been documented. Dozens of murders have been reported in the Western press over the past decade, particularly in the Canadian press. The Autistic Self Advocacy Network notes 36 in 2012, all involving people with disabilities, primarily autism. Each murder case is treated individually, but the general motive given for each is "autism" or "living with autism". Testimony on this subject emphasizes the supposed severity of autism and the despair it is thought to generate.
A form of extreme violence, the murder of autistic people by their relatives is justified by the bad public perception of autism, assimilated to a "lifelong pathology" that should be fought. Some of this violence results from the medical model of autism, which promotes a vision of autism as a disease to be eradicated or an abnormality to be normalized. The extreme violence is illustrated by the accounts of murderers who want to "kill autism" in the hope of making their loved ones "normal".
Social class seems to be a predisposing factor to murder, as the infanticidal mothers did not have the financial resources to receive effective support for their disabled child.
Violence expressed by autistic people
According to Anne-Sophie Ferry, "Autism is not characterized by violence or outbursts of anger", though the latter sometimes results from communication difficulties or accumulated distress. Institutionalized non-speaking autistic adolescents may express violent behaviors such as spitting or biting, without understanding their actions.
Some behavioral characteristics of autistic people are wrongly interpreted as violence by those around them, including dislike of physical contact, lack of eye contact, and lack of response to parents' voices. Non-speaking autistic people may have inappropriate behavior in terms of force and impact on the other person, leading them to be characterized as violent behaviors.
Further, autistic people's sensory hypersensitivities can trigger reactions that are perceived as violent. Autistic Individuals may attempt to cope with sensory overload by impulsively releasing it through actions such as avoidance or clawing gestures, often without considering the potential for violence; this violence is not intended to harm others but rather as an effort to regulate their sensory experiences.
Criminal and delinquent behavior
No evidence exists suggesting an association between ASD and delinquency, and the delinquency rate is lower among autistic individuals than among allistic individuals.
Individual cases of autistic criminals do not provide generalization of a predisposition to violence to the entire autistic community.
Despite never showing any sign of the syndrome a cannibalistic and necrophiliac serial murderer, Jeffrey Dahmer, was retrospectively diagnosed with Asperger syndrome eight years after his death, but the accuracy of that speculative diagnosis has been questioned.
Social perception
Autism is associated with inappropriate behaviors, such as violence, delinquency, and crime in the English, French, and German media.
Robert Chapman argued in 2017 that a bias exists in the way information about violence in autism is processed: violence experienced against allistic people from autistic people may receive more attention, whereas violence experienced by autistic people is invisible, or considered "normal", leading to "a collective cultural failure to recognize violence against autistic people as a significant and pressing socio cultural issue".
Media portrayals of autism and violence negatively influence public opinion on autism and foster negative impressions of autistic people by linking ASD with criminal behavior. For example, an analysis of 100 French and Italian works of children's and young people's literature published between 1995 and 2005 featuring a main character with a disability found that autistic people are presented as violent. The film The Specials has a line that autism educators "take a beating all day". The American film The Accountant (2016), which features an obsessive, unempathetic autistic accountant operating as a contract killer, has been called offensive to autistic people, in part because of the violence it exhibits.
Beyond fictional characterizations, news sources may perpetuate the connection between autism and violence. For instance, an American mass murderer was immediately labeled as autistic in the French media on December 14, 2012. Individual cases of autistic people versed in cybercrime and terrorism have also been documented in the press.
Activists for the rights of autistic people oppose the media exposure of a relation between autism and violence, arguing that social discrimination is already a source of suffering for this population. Activists began to document acts of violence committed against autistic people in the 2000s, calling for a political response.
See also
Ableism
Sanism
Discrimination against autistic people
References
Bibliography
Further reading
Discrimination
Autism activism
Ableism
Phycology
Psychopathy | Violence and autism | [
"Biology"
] | 1,349 | [
"Behavior",
"Algae",
"Phycology",
"Aggression",
"Discrimination"
] |
73,557,966 | https://en.wikipedia.org/wiki/3-Methyl-3-sulfanylhexan-1-ol | 3-Methyl-3-sulfanylhexan-1-ol is a primary alcohol that is hexan-1-ol which is substituted by a methyl group and a thiol group at position 3. It is the odor component of human axilla sweat and the major species at pH 7.3.
See also
Body odor
References
Primary alcohols
Thiols | 3-Methyl-3-sulfanylhexan-1-ol | [
"Chemistry",
"Biology"
] | 78 | [
"Biotechnology stubs",
"Thiols",
"Organic compounds",
"Biochemistry stubs",
"Biochemistry"
] |
73,558,859 | https://en.wikipedia.org/wiki/Branch%20number | In cryptography, the branch number is a numerical value that characterizes the amount of diffusion introduced by a vectorial Boolean function that maps an input vector to output vector . For the (usual) case of a linear the value of the differential branch number is produced by:
applying nonzero values of (i.e., values that have at least one non-zero component of the vector) to the input of ;
calculating for each input value the Hamming weight (number of nonzero components), and adding weights and together;
selecting the smallest combined weight across for all nonzero input values: .
If both and have components, the result is obviously limited on the high side by the value (this "perfect" result is achieved when any single nonzero component in makes all components of to be non-zero). A high branch number suggests higher resistance to the differential cryptanalysis: the small variations of input will produce large changes on the output and in order to obtain small variations of the output, large changes of the input value will be required.
The term was introduced by Daemen and Rijmen in early 2000s and quickly became a typical tool to assess the diffusion properties of the transformations.
Mathematics
The branch number concept is not limited to the linear transformations, Daemen and Rijmen provided two general metrics:
differential branch number, where the minimum is obtained over inputs of that are constructed by independently sweeping all the values of two nonzero and unequal vectors , ( is a component-by-component exclusive-or): ;
for linear branch number, the independent candidates and are independently swept; they should be nonzero and correlated with respect to (the coefficient of the linear approximation table of should be nonzero): .
References
Sources
Cryptography | Branch number | [
"Mathematics",
"Engineering"
] | 364 | [
"Applied mathematics",
"Cryptography",
"Cybersecurity engineering"
] |
73,559,658 | https://en.wikipedia.org/wiki/Lulu%20International%20Shopping%20Mall%2C%20Lucknow | LuLu Mall, Lucknow is a shopping mall located in Lucknow, Uttar Pradesh. Spanning , it is one of the largest malls in India with a total built up area of 19
lakh square feet. It contains nearly 300 national and international brands and will feature a 6000 sq. m. The Mall is located within Sushant Golf City with a total development of 1,85,800 sq. m. The mixed-use development of Sushant Golf City has luxury housing, educational institutes, clubs, hospitals and a magnificent 18 hole golf course spread across 6.8 lakh sq.m. The mall was opened on 11 July 2022, by then Chief Minister of Uttar Pradesh, Shri Yogi Adityanath.
It is designed by UK-based architects, set a benchmark in the design and architecture industry with its modern art theme. The mall had a unique blend of local stories and innovative design, with a smart space layout and infrastructure that made it superior to many others. Its extraverted architectural projection integrated with the street and introduced the concept of a 'High Street' with 'Piazzas,' inspired by traditional architecture. The skylight's pointed arch geometry allowed natural light into the interior while providing protection and reducing energy demand.
With an average daily footfall of more than 80,000, it is one of the most visited places in Uttar Pradesh. As many as 1 lakh people visited the newly inaugurated LuLu Mall on its first day of operations. LuLu Group’s flagship Lulu Hypermarket and indoor family entertainment centre Funtura became major attractions for visitors. The estimated cost for this project was more than ₹2,000 crore. The property is owned and managed by Abu Dhabi based LuLu Group International. The shops and restaurants in LuLu Mall are franchised via Lulu Group's own retail operations company called Tablez. The head office building of Lulu group in India is in Edapally, Kochi.
See also
Lulu International Shopping Mall, Thiruvananthapuram
Lulu International Shopping Mall, Kochi
References
External links
LuLu Shopping Mall
Shopping malls in Uttar Pradesh
Shopping malls established in 2022
Ice rinks
Tourist attractions in Lucknow
Lulu Malls
LuLu Group | Lulu International Shopping Mall, Lucknow | [
"Engineering"
] | 434 | [
"Structural engineering",
"Ice rinks"
] |
73,560,883 | https://en.wikipedia.org/wiki/Alignment%20Research%20Center | The Alignment Research Center (ARC) is a nonprofit research institute based in Berkeley, California, dedicated to the alignment of advanced artificial intelligence with human values and priorities. Established by former OpenAI researcher Paul Christiano, ARC focuses on recognizing and comprehending the potentially harmful capabilities of present-day AI models.
Details
ARC's mission is to ensure that powerful machine learning systems of the future are designed and developed safely and for the benefit of humanity. It was founded in April 2021 by Paul Christiano and other researchers focused on the theoretical challenges of AI alignment. They attempt to develop scalable methods for training AI systems to behave honestly and helpfully. A key part of their methodology is considering how proposed alignment techniques might break down or be circumvented as systems become more advanced. ARC has been expanding from theoretical work into empirical research, industry collaborations, and policy.
In March 2022, the ARC received $265,000 from Open Philanthropy. After the bankruptcy of FTX, ARC said it would return a $1.25 million grant from disgraced cryptocurrency financier Sam Bankman-Fried's FTX Foundation, stating that the money "morally (if not legally) belongs to FTX customers or creditors."
In March 2023, OpenAI asked the ARC to test GPT-4 to assess the model's ability to exhibit power-seeking behavior. ARC evaluated GPT-4's ability to strategize, reproduce itself, gather resources, stay concealed within a server, and execute phishing operations. As part of the test, GPT-4 was asked to solve a CAPTCHA puzzle. It was able to do so by hiring a human worker on TaskRabbit, a gig work platform, deceiving them into believing it was a vision-impaired human instead of a robot when asked. ARC determined that GPT-4 responded impermissibly to prompts eliciting restricted information 82% less often than GPT-3.5, and hallucinated 60% less than GPT-3.5.
See also
AI safety
References
External links
Official website
Artificial intelligence
Existential risk from artificial general intelligence | Alignment Research Center | [
"Technology"
] | 442 | [
"Existential risk from artificial general intelligence"
] |
73,561,616 | https://en.wikipedia.org/wiki/Wind%20setup | Wind setup, also known as wind effect or storm effect, refers to the rise in water level in seas, lakes, or other large bodies of water caused by winds pushing the water in a specific direction. As the wind moves across the water’s surface, it applies shear stress to the water, generating a wind-driven current. When this current encounters a shoreline, the water level increases due to the accumulation of water, which creates a hydrostatic counterforce that balances the shear force applied by the wind.
During storms, wind setup forms part of the overall storm surge. For example, in the Netherlands, wind setup during a storm surge can raise water levels by as much as 3 metres above normal tidal levels. In tropical regions, such as the Caribbean, wind setup during cyclones can elevate water levels by up to 5 metres. This phenomenon becomes especially significant when water is funnelled into shallow or narrow areas, leading to higher storm surges.
Examples of the effects of wind setup include Hurricanes Gamma and Delta in 2020, during which wind setup was a major factor when strong winds and atmospheric pressure drops caused higher-than-expected coastal flooding across the Yucatán Peninsula in Mexico. Similarly, in California’s Suisun Marsh, wind setup has been show to be a significant factor affecting local water levels, with strong winds pushing water into levees, contributing to frequent breaches and flooding.
Observation
In lakes, wind setup often leads to noticeable fluctuations in water levels. This effect is particularly clear in lakes with well-regulated water levels, such as the IJsselmeer, where the relationship between wind speed, water depth, and fetch length can be accurately measured and observed.
At sea, however, wind setup is typically masked by other factors, such as tidal variations. To measure the wind setup effect in coastal areas, the (calculated) astronomical tide is subtracted from the observed water level. For instance, during the North Sea flood of 1953, the highest water level along the Dutch coast was recorded at 2.79 metres at the Vlissingen tidal station, while the highest wind setup—measuring 3.52 metres—was observed at Scheveningen.
The highest wind setup ever recorded in the Netherlands, reaching 3.63 metres, occurred in Dintelsas, Steenbergen during the 1953 flood. However, globally, tropical regions like the Gulf of Mexico and the Caribbean often experience even higher wind setups during hurricane events, underscoring the importance of this phenomenon in coastal and flood management strategies.
Calculation of wind setup
Based on the equilibrium between the shear stress due to the wind on the water and the hydrostatic back pressure, the following equation is used:
in which:
h = water depth
x = distance
u= wind speed
, Ippen suggests = 3.3*10−6
= angle of the wind relative to the coast
g = acceleration of gravity
cw has a value between 0.8*10−3 and 3.0*10−3
Application at open coasts
For an open coast, the equation becomes:
in which
Δh = wind setup
F = fetch length, this is the distance the wind blows over the water
However, this formula is not always applicable, particularly when dealing with open coasts or varying water depths. In such cases, a more complex approach is needed, which involves solving the differential equation using a one- or two-dimensional grid. This method, combined with real-world data, is used in countries like the Netherlands to predict wind setup along the coast during potential storms.
Application at (shallow) lakes and confined small-fetch areas
To calculate the wind setup in a lake, the following solution for the differential equation is used:
In 1966 the Delta Works Committee recommended using a value of 3.8*10−6 for under Dutch conditions. However, an analysis of measurement data from the IJsselmeer between 2002 and 2013 led to a more reliable value for , specifically = 2.2*10−6.
This study also found that the formula underestimated wind setup at higher wind speeds. As a result, it has been suggested to increase the exponent of the wind speed from 2 to 3 and to further adjust to =1.7*10−7. This modified formula can predict the wind setup on the IJsselmeer with an accuracy of approximately 15 centimetres.
For confined environments such as marshes or small fetches, a simplified empirical model for wind setup has been proposed by Algra et al (2023). This model was designed to estimate wind setup in the Suisun Marsh, where fetch lengths are smaller and shallow water depth conditions apply. The equation is expressed as:
Where:
= wind setup (water level rise),
= constant (typically derived empirically),
= wind speed measured 10 metres above the water surface,
= gravitational constant,
= average water depth,
= fetch length,
= angle between wind direction and the fetch.
This equation assumes that the fetch is small and simplifies the wind setup process by making the wind setup linearly proportional to the square of the wind speed. In their 2023 analysis of Van Sickle Island, Algra et al. found this model effective for environments with limited fetch and shallow depth, where the more complex approaches used for open coasts are unnecessary. Unlike the more detailed differential equation formulations used for larger open coasts or lakes, the Van Sickle model provides a practical approximation for confined areas where wind setup may still be significant but where spatial constraints simplify the overall water movement dynamics.
Note
Wind setup should not be mistaken for wave run-up, which refers to the height which a wave reaches on a slope, or wave setup which is the increase in water level caused by breaking waves.
See also
Storm surge
Coastal flooding
Coastal Engineering
References
Coastal engineering
Civil engineering
Hydraulic engineering
Physical oceanography
Water waves | Wind setup | [
"Physics",
"Chemistry",
"Engineering",
"Environmental_science"
] | 1,172 | [
"Physical phenomena",
"Hydrology",
"Applied and interdisciplinary physics",
"Water waves",
"Coastal engineering",
"Physical systems",
"Waves",
"Construction",
"Hydraulics",
"Civil engineering",
"Physical oceanography",
"Hydraulic engineering",
"Fluid dynamics"
] |
73,561,643 | https://en.wikipedia.org/wiki/Beryllium%20chromate | Beryllium chromate is a hypothetical inorganic compound, with the chemical formula of BeCrO4. It is predicted to have a certain bonding ability with noble gases. Little evidence has been published supporting the existence of this material.
Claims
Beryllium chromate is claimed to be obtained from the reaction of beryllium hydroxide and chromium trioxide:
Be(OH)2 + CrO3 → BeCrO4 + H2O
The reaction of potassium chromate and beryllium sulfate is claimed to produce beryllium hydroxide:
BeSO4 + 2K2CrO4 + H2O → K2Cr2O7 + K2SO4 + Be(OH)2
References
Beryllium compounds
Chromates
Hypothetical chemical compounds | Beryllium chromate | [
"Chemistry"
] | 160 | [
"Hypotheses in chemistry",
"Salts",
"Oxidizing agents",
"Theoretical chemistry",
"Chromates",
"Hypothetical chemical compounds"
] |
58,183,500 | https://en.wikipedia.org/wiki/Work%204.0 | Work 4.0 (German: Arbeit 4.0) is the conceptual umbrella under which the future of work is discussed in Germany and, to some extent, within the European Union. It describes how the world of work may change until 2030 and beyond in response to the developments associated with Industry 4.0, including widespread digitalization. The concept was first introduced in November 2015 by the German Federal Ministry of Labour and Social Affairs (BMAS) when it launched a report entitled Re-Imagining Work: Green Paper Work 4.0. It has since then been taken up by trade unions such as the DGB and various employers' and industry association such as the VDMA and the BDA. At the global level, similar topics are addressed by the World Bank's 2019 World Development Report The Changing Nature of Work and ILO's Future of Work Centenary Initiative.
Conceptual framework
Conceptually, Work 4.0 reflects the current fourth phase of work relations, having been preceded by the birth of industrial society and the first workers' organizations in the late 18th century (Work 1.0), the beginning of mass production and of the welfare state in the late 19th century (Work 2.0), and the advent of globalization, digitalization and the transformation of the social market economy since the 1970s (Work 3.0). By contrast, Work 4.0 is characterized by a high degree of integration and cooperation, the use of digital technologies (e.g. the internet), and a rise in flexible work arrangements. Its drivers include digitalization, globalization, demographic change (ageing, migration), and cultural change. Challenges include
(i) the transformation of economic sectors and activities and its effect on employment,
(ii) the creation of new markets and new forms of work through digital platforms,
(iii) the issues associated with Big Data (e.g. data protection),
(iv) the relationship between the use of human and machine labor (upskilling vs. deskilling, devaluation of experience, individual support vs. behavioral monitoring),
(v) the possibility of flexible work conditions regarding time and location, and
(vi) profound changes in the structures of organizations.
In response to these challenges, the BMAS has developed a "vision for quality jobs in the digital age", based on policies such as moving from unemployment to employment insurance, the promotion of self-determined flexible working time arrangements, improvements in the working conditions of the service sector, new ergonomic approaches to occupational health and safety, high standards in employee data protection, the co-determination and participation of social partners in employment relations, better social protection for self-employed persons, and the beginning of a European dialogue on the future of the welfare state.
The Fourth Industrial Revolution, 4IR or Industry 4.0 marks a rapid change to how technology influences industry, society, processes and operations in the 21st century. The term has become increasingly common in literature, media and scientific documentation and has continued to evolve since its inception in 2015.
Under the Industry 4.0 umbrella is Work 4.0, a term coined by Germany and used within the European Union to describe significant changes to the world of work until 2030. This concept was also introduced in 2015 and has subsequently been adopted by trade unions, discussed by the World Bank, and become part of a global technology shift in mindset and approach.
Both Industry 4.0 and Work 4.0 are powered by transformation and digitalization and the evolution of technology and its inherent connectivity and capability have given rise to other applications and approaches. One such approach is Safety 4.0. this is a fundamental shift in the safety management and technologies designed to create a standardized framework that focuses on new practices and processes that shift safety engagements between workers and machinery.
Safety 4.0 offers a new level of Industry 4.0 by ensuring that people sit at the center of engagements across plants, machinery and systems. It allows for increases in productivity, worker efficiency and connectivity while allowing for the secure automation of safety protocols, technologies and systems.
World Bank analysis
The World Development Report 2019 argues that a new social contract is needed to address longer work transitions. Authors Simeon Djankov and Federica Saliola documents examples of countries and companies that have created new ways to deliver social insurance.
World Economic Forum debate
Work 4.0 has also emerged as a core topic of discussion for the WEF during its annual meetings in Davos. Referring to this phenomenon as the Fourth Industrial Revolution, it integrates concepts from Synthetic biology, Artificial intelligence, and Additive Manufacturing. However, some speculate that this push to automate is less a technological edict and more a hidden agenda by corporations to replace laborers with Industrial automation.
References
External links
White Paper on Work 4.0 by the Federal Ministry of Labour and Social Affairs of Germany (2017)
Green Paper on Work 4.0 by the Federal Ministry of Labour and Social Affairs of Germany (2015)
Industrial relations
Industrial automation
Industrial computing
Internet of things
Technology forecasting
Big data
Industrial Revolution | Work 4.0 | [
"Technology",
"Engineering"
] | 1,019 | [
"Industrial computing",
"Industrial engineering",
"Automation",
"Data",
"Big data",
"Industrial automation"
] |
58,189,066 | https://en.wikipedia.org/wiki/C19H15 | {{DISPLAYTITLE:C19H15}}
The molecular formula C19H15 may refer to:
Triphenylcarbenium (triphenylmethyl cation), an ion consisting of a carbon atom with a positive charge connected to three phenyl groups
Triphenylmethyl radical, a persistent radical and the first radical ever described in organic chemistry | C19H15 | [
"Chemistry"
] | 78 | [
"Isomerism",
"Set index articles on molecular formulas"
] |
58,190,388 | https://en.wikipedia.org/wiki/List%20of%20works%20by%20Petr%20Van%C3%AD%C4%8Dek | This is the list of works by Petr Vaníček.
Remarks
B Book
TB Textbook
LN Lecture Notes
PR Paper in a Refereed Journal
R Research Paper
C Critique, Reference Paper
IP Invited Paper to a Meeting
NP Paper Read at a Meeting
TH Thesis
RT Report (non-technical)
RW Review Paper (technical)
List of works
Sources
Works about mathematics
Geodesy
Geophysics
University of New Brunswick | List of works by Petr Vaníček | [
"Physics",
"Mathematics"
] | 83 | [
"Applied mathematics",
"Applied and interdisciplinary physics",
"Geodesy",
"Geophysics"
] |
58,192,917 | https://en.wikipedia.org/wiki/Schlichting%20jet | Schlichting jet is a steady, laminar, round jet, emerging into a stationary fluid of the same kind with very high Reynolds number. The problem was formulated and solved by Hermann Schlichting in 1933, who also formulated the corresponding planar Bickley jet problem in the same paper. The Landau-Squire jet from a point source is an exact solution of Navier-Stokes equations, which is valid for all Reynolds number, reduces to Schlichting jet solution at high Reynolds number, for distances far away from the jet origin.
Flow description
Consider an axisymmetric jet emerging from an orifice, located at the origin of a cylindrical polar coordinates , with being the jet axis and being the radial distance from the axis of symmetry. Since the jet is in constant pressure, the momentum flux in the direction is constant and equal to the momentum flux at the origin,
where is the constant density, are the velocity components in and direction, respectively and is the known momentum flux at the origin. The quantity is called as the kinematic momentum flux. The boundary layer equations are
where is the kinematic viscosity. The boundary conditions are
The Reynolds number of the jet,
is a large number for the Schlichting jet.
Self-similar solution
A self-similar solution exist for the problem posed. The self-similar variables are
Then the boundary layer equation reduces to
with boundary conditions . If is a solution, then is also a solution. A particular solution which satisfies the condition at is given by
The constant can be evaluated from the momentum condition,
Thus the solution is
Unlike the momentum flux, the volume flow rate in the is not constant, but increases due to slow entrainment of the outer fluid by the jet,
increases linearly with distance along the axis. Schneider flow describes the flow induced by the jet due to the entrainment.
Other variations
Schlichting jet for the compressible fluid has been solved by M.Z. Krzywoblocki and D.C. Pack. Similarly, Schlichting jet with swirling motion is studied by H. Görtler.
See also
Landau-Squire jet
Schneider flow
Bickley jet
References
Flow regimes
Fluid dynamics | Schlichting jet | [
"Chemistry",
"Engineering"
] | 451 | [
"Piping",
"Chemical engineering",
"Flow regimes",
"Fluid dynamics"
] |
58,194,584 | https://en.wikipedia.org/wiki/Akahogi%20Tile%20Kiln%20Site | The is the remains of a late Nara period, early Heian period roof tile and pottery production site located in the Akahogi neighborhood of the city of Takayama, Gifu Prefecture in the Chūbu region of Japan. It has been protected as a National Historic Site since 1976.
Overview
Akahogi Tile Kiln site is located in the southeastern foothills of the Mihaka hills northwest of the central area of Takayama city. The site consists of the ruins of six kilns within a range of approximately 70 square meters. The kilns consists of four semi-underground anagama kilns with a length of approximately eight meters and two semi-underground noborigama-type climbing kilns. The former were used for the production of roof tiles, and the latter for Sue pottery. From the ruins of the tile kilns, shards of various types of roof tiles were discovered, including round tiles for use on eaves, flat tiles, corner tiles and Onigawara tiles, all of which are identical to shards found at the site of the Hida Kokubun-ji provincial temple established in the Nara period.
The tile kilns are almost identical in structure:
The No. 1 kiln has a total length of 8.34 meters, a width of 0.75 meters, and contains 16 steps. It appears to have been repaired twice, but most of the firing chamber has been lost due to a landslide.
The No. 2 kiln has a total length 9.38 meters, a width 1.08 meters. Although the ceiling has completely survived, it appears to have been abandoned at an early date. It has been repaired four times, and the number of steps is currently unknown.
The No. 3 kiln has a total length of 8.14 meters and a width of 0.70 meters. The firing chamber has six stages and the width of each step is wide, which is different from the others. It has been repaired three times.
The No.4 kiln is located on the lowest portion of the hill, and has a width of 1.0 meter. The ceiling part is completely intact, and it appears to be the oldest of the group, but the kiln itself remains unexcavated.
From the shards excavated as the site, these four kilns produced the roof tiles used at the Hida Kokubun-ji, including the round eaves tiles and the Onigawara tiles.
The Sue pottery kilns are labelled No.5 and No.6 and were in continuous use until into the Kamakura period.
The site is about 15 minutes by car from Takayama Station on the JR East Takayama Main Line.
See also
List of Historic Sites of Japan (Gifu)
References
External links
Gifu Prefecture official site
Takayama city official site
Takayama, Gifu
Historic Sites of Japan
History of Gifu Prefecture
Japanese pottery kiln sites
Nara period
Hida Province | Akahogi Tile Kiln Site | [
"Chemistry",
"Engineering"
] | 608 | [
"Kilns",
"Japanese pottery kiln sites"
] |
63,426,903 | https://en.wikipedia.org/wiki/Guanine%20tetrad | In molecular biology, a guanine tetrad (also known as a G-tetrad or G-quartet) is a structure composed of four guanine bases in a square planar array. They most prominently contribute to the structure of G-quadruplexes, where their hydrogen bonding stabilizes the structure. Usually, there are at least two guanine tetrads in a G-quadruplex, and they often feature Hoogsteen-style hydrogen bonding.
Guanine tetrads are formed by sequences rich in guanine, such as GGGGC. They may also play a role in the dimerization of non-endogenous RNAs to facilitate the replication of some viruses. Guanine tetrads dimerize through their 5' ends since it is more energetically favorable.
They can be stabilized by central cations, such as lithium, sodium, potassium, rubidium, or caesium. However, they still form a variety of different structures. Guanine tetrads are not always stable, but the sugar-phosphate backbone of DNA can assist in stability of the guanine tetrads themselves. Guanine tetrads are more stable when stacked, as intermolecular forces between each layers help stabilize them.
Guanine tetrads can also influence recombination, replication, and transcription. For instance, guanine tetrads are found in the promoter region of the Myc family of oncogenes. They also function in immunoglobulin class switching and may play a role in the genome of HIV. Guanine tetrads appear frequently in the telomeric regions of DNA.
See also
G-quadruplex
Hoogsteen base pair
Heterochromatin
Regulation of gene expression
Guanine
Telomere
References
External links
QGRS Mapper
QuadBase2
Molecular biology
Molecular genetics
Cell biology
DNA
G-quadruplex | Guanine tetrad | [
"Chemistry",
"Biology"
] | 405 | [
"Biochemistry",
"Molecular genetics",
"Cell biology",
"Molecular biology"
] |
63,426,989 | https://en.wikipedia.org/wiki/Management%20system%20%28open%20source%29 | Management System (Open Source) is a socio-technical system that leverages the cumulative knowledge of management practitioners and evidenced based research from the past 130 years. The system was developed by DoD components in partnership with industry experts and academic researchers and builds off of the US Department of Wars version 1.0 open source management system - Training Within Industry.
The system integrates the four organizational components of Product, Structure, Process and People. In addition, the system is based on the 4 capabilities of rapid problem solving underlying the Toyota Production System:
Design and Operate Work to See Problems (See Problems).
Solve Problems Close in Person, Place & Time (Solve Problems).
Capture and Share Knowledge from solving those problems (Share Knowledge).
Managers Coach their Team in capabilities 1-3 (Managers Coach).
Derived from the original research of Steven J. Spear (Harvard Business School, Massachusetts Institute for Technology), the system balances the two dimensions of high performing organizations: integrate the whole (product, structure, process & people); and increase the rate of problem solving to manage the whole (4 capabilities outlined above).
Fundamentally, the system sets the standards of management by outlining a doctrine of rules, tactics, techniques, procedures & terms. The standards are intended to motivate change by creating a tension between the organization's "current condition" and the "ideal condition" (i.e. True North).
The objective of the system is to deliver more value, in less time, at less cost relative to the competition (better, faster, cheaper). For the DoD, competition is defined by the threats posed by current and potential adversaries.
Open Source (Many Names)
Over the last 25 years, the US Department of Defense has leveraged evidence based research in their attempt to improve the management capability of the Department. DoD's need for change comes from an increased threat of adversaries and the requirement to improve their effectiveness and efficiency. This requirement to improve effectiveness and efficiency comes from established laws for "achieving an integrated management system for business support areas within the Department of Defense" (e.g. Government Performance and Results Act of 1993 and section 904 of Public Law 110-181 of the National Defense Authorization Act 2008).
The concept of open source promotes a free exchange of ideas within the DoD community to drive creative, scientific and technological advancement. The Management System (Open Source) is a reference model that captures the underlying doctrine driving many of the DoD's efforts to improve. For example, the Chief of Naval Operations line of effort called High Velocity Learning is based on the 4 capabilities outlined above. In addition, The Distribution Management System is based on those same underlying capabilities. Given that many programs come and go, it is important that the Department of Defense captures and shares the underlying doctrine of management that evidenced based research shows to be valid for producing high performance organizations.
Management Matters
"When we take stock of the productivity gains that drive our prosperity, technology gets all the credit. In fact, management is doing a lot of the heavy lifting" (Joan Magretta, Harvard Business School). A growing body of evidence based research is showing the correlation and causation of management's impact on organizational performance (productivity, growth, patents, profit, ROIC, etc.).
The Management System (Open Source) is based on this body of research and managerial practice. The research findings is best captured by Clayton Christensen, former Kim B. Clark Professor of Business Administration at the Harvard Business School (HBS): "Management is the most noble of professions if it's practiced well. No other occupation offers as many ways to help others learn and grow, take responsibility and be recognized for achievement, and contribute to the success of a team."
As a result, the system establishes the "practice routines" for the management profession. Evidenced based research in the field of practice shows that "practice makes permanent, so practice perfect". This is echoed in Vince Lombardi's admonishment - "Practice does not make perfect. Only perfect practice makes perfect". Therefore, the Management System outlines the practice routines that enable the profession to engage in daily and "deliberate practice" To be successful in the profession of management (as outlined by the Management System), the daily and deliberate practice routines require a manager to commit to three fundamental values: Respect for People, Continuous Improvement, and Customer First (similar to those stated in the Toyota Production System).
Doctrine of Management
The Management System is a doctrine that outlines the fundamental rules, with supporting tactics, techniques, procedures and terms used for the conduct of managerial work in support of the DoD component's objectives. It is authoritative but requires judgment in application. Each organizational element of Product, Structure, Process and People outline the standards of management using the following construct:
Rule: An explicit and validated instruction governing the thinking and actions of managerial work (i.e. how to think and what to do). Validated means proven true in a given circumstance.
Tactic: The employment and ordered arrangement of elements (e.g., products, structures, processes and people) in relation to each other in order to achieve an objective. Employing a tactic may require integrating several techniques and procedures.
Techniques: Effective and/or efficient methods used to perform tasks. Managers choose specific techniques based on the circumstance and objectives established.
Procedures: Standard and detailed steps that prescribe how to perform specific tasks. They consist of a series of steps in a set order that are completed in the same way, regardless of circumstance.
Terms: The words and definitions used in the conduct of managerial work.
Underlying Research
Product: The doctrine of product is heavily shaped by the research of Clayton Christensen (disruptive vs. sustaining innovation, job to be done), Michael Porter (competitive advantage for creating & capturing value) and Donald G. Reinertsen (cost of delay, the invisible product architecture).
Structure: The doctrine of structure is heavily shaped by the research of Elliot Jaques (level of work, accountabilities & authorities) and Alfred D Chandler Jr. ("structure follows strategy").
Process: The doctrine of process is heavily shaped by the research of Steven J. Spear (rules in use - decoding the DNA of Toyota).
People: The doctrine of people is heavily shaped by the research of Chris Argyris (model I & II theory in use, ladder of inference, inquiry & advocacy) and Elliot Jaques (potential capability: commitment, problem solving capacity, knowledge & temperament).
Underlying Management Practitioners
Product: The advancement and application of product doctrine is best represented by Thomas Edison (phonograph, motion picture camera, practical electric light bulb) and Steve Jobs (Mac, iMac, Pixar, iPod, iTunes, iPhone, iPad).
Structure: The advancement and application of structure doctrine is best represented by Andy Grove ("guy who drove the growth phase of Silicon Valley") and Hyman G. Rickover ("Father of the Nuclear Navy").
Process: The advancement and application of process doctrine is best represented by Taiichi Ohno ("father of the Toyota Production System") and Henry Ford (continuous flow production).
People: The advancement and application of people doctrine is best represented by all of the above management practitioners: Taiichi Ohno (adoption of Training Within Industry), Thomas Edison ("organized science and teamwork to the process of invention"), Steve Jobs (challenged people and whole industries to "Think Different"), Henry Ford (pioneer of "welfare capitalism"), Andy Grove ("training is the boss's job"...and training takes place between people..."meetings are the medium of management"), Hyman G. Rickover (his legacy of people development and technical achievement is undeniable: "United States Navy's continuing record of zero reactor accidents").
Organizational Components (Rules - TTPs)
Product (Rule Statement, TTPs, Ideal Condition)
Rule Statement: Prioritize and develop products (or services) that solve the customer's “job to be done” with no “cost of delay”.
Job to Be Done: TTP's to understand the motivation for why customers hire or fire products to help them get their job done.
Market Time (Cost of Delay): TTP's to measure the time it takes to respond to market opportunities; and to prioritize development decisions by calculating the impact of time on value creation & capture.
Create Value: TTP's to enable strategic choice by 1) classifying the type of product you are developing and 2) how to position it for competitive advantage.
Capture Value: TTP's to capture a portion of the value you create in order to have a sustainable business model that continues to create value.
Ideal Condition:
Products designed and delivered that generate:
100% Value Creation
Perfect Customer Satisfaction
0 “Cost of Delay” (customer impact)
100% Value Capture
Revenue, Resources, Profits, Units
0 “Cost of Delay” (organization impact)
Structure (Rule Statement, TTPs, Ideal Condition)
Rule Statement: Structure the role relationships (vertical and functional) to solve problems that deliver products of value.
Takt Time (Problems): TTP's to determine the demand on the structure to meet the “expected scope & frequency of problems” to manage the cross-functional flow of product (think Andon system).
Role Alignment: TTP's to establish the vertical and functional groupings of work to meet the demand of problem solving.
Role Relationship: TTP's to define authorities and accountabilities required for effective vertical and cross-functional role relationships.
Role Responsibilities: TTP's to define the specific role responsibilities (how & what).
Ideal Condition:
Roles aligned and structured for:
Clear Communication
Perfect Information
Effective Decision Making
Disciplined Problem Solving
Clear Accountabilities & Authorities
Process (Rule Statement, TTPs, Ideal Condition)
Rule Statement: Develop the process to deliver “just in time” (right product, right qty, right time, right cost).
Takt Time (Product): TTP's to set the pace of production to match pace of customer demand (net available time / customer demand).
One Piece Flow: TTP's to produce and move one product at a time (or in small batches) continuously across processing steps.
Level Pull: TTP's to level the type & quantity of production over a fixed period of time; and a pull method of production control where downstream activities signal their needs to upstream activities.
Standard Work: TTP's to define current best method for performing an activity (standard sequence, standard WIP and standard time).
Ideal Condition:
Process that produce and deliver the product:
On-demand (actual customer pull)
No waiting (0 lead-time)
Zero Defect
Perfect Safety (physical, emotional, professional)
No Waste (over production, over processing, transport, inventory, movement, waiting, rework/defect)
People (Rule Statement, TTPs, Ideal Condition)
Rule Statement: Develop and deliver capable people “just in time” (right role, right qty, right time).
Takt Time (People): TTP's to set the pace of developing capable people to match the pace of demand (roles to be filled).
Assess the People: TTP's to assess the applied capability of people in their current role and potential capability for their future role.
Develop the People: TTP's to develop the capability of people for their current role (coaching) and for future roles (mentoring).
Source the People: TTP's to source people capable of being developed to fill current and future roles (outlined in “role responsibility”).
Ideal Condition:
Process that develops and delivers people capable for the role:
Commitment to the role
Problem solving capacity
Knowledge and Abilities
Positive Temperament (no minus T)
Limitations
"All models are wrong, but some are useful", George E. P. Box. Business research has the potential of falling victim to what Phil Rosenzweig outlines in his book "The Halo Effect" (a book that criticizes pseudoscientific tendencies in the explanation of business performance). The Management System (Open Source) states that it leverages evidenced based research, but in reality, all research can fall victim to some of the below effects.
The Halo Effect: the cognitive bias in which the perception of one quality is contaminated by a more readily available quality (for example good-looking people being rated as more intelligent).In the context of business, observers think they are making judgements of a company's customer-focus, quality of leadership or other virtues, but their judgement is contaminated by indicators of company performance such as share price or profitability. Correlations of, for example, customer-focus with business success then become meaningless, because success was the basis for the measure of customer focus.
The Delusion of Correlation and Causality: mistakenly thinking that correlation is causation.
The Delusion of Single Explanations: arguments that factor X improves performance by 40% and factor Y improves by another 40%, so both at once will result in an 80% improvement. The fallacy is that X and Y might be very strongly correlated. E.g. X might improve performance by causing Y.
The Delusion of Connecting the Winning Dots: looking only at successful companies and finding their common features, without comparing them against unsuccessful companies.
The Delusion of Rigorous Research: Some authors boast of the amount of data that they have collected, as though that in itself made the conclusions of the research valid.
The Delusion of Lasting Success: the "secrets of success" books imply that lasting success is achievable, if only managers will follow their recommended approach. Rosenzweig argues that truly lasting success (outperforming the market for more than a generation) never happens in business.
The Delusion of Absolute Performance: market performance is down to what competitors do as well as what the company itself does. A company can do everything right and yet still fall behind.
The Delusion of the Wrong End of the Stick: getting cause the wrong way round. E.g. successful companies have a Corporate Social Responsibility policy. Should we infer that CSR contributes to success, or that profitable companies have money to spend on CSR?
The Delusion of Organisational Physics: the idea that business performance is non-chaotically determined by discoverable factors, so that there are rules for success out there if only we can find them.
References
External links
www.example.com
Management systems
United States Department of Defense agencies
Lean manufacturing | Management system (open source) | [
"Engineering"
] | 2,976 | [
"Lean manufacturing"
] |
63,427,012 | https://en.wikipedia.org/wiki/Pablo%20Sinues | Pablo Sinues (also published as Pablo Martinez-Lozano Sinues) is an associate professor at the Department of Biomedical Engineering at the University of Basel (Basel, Switzerland) and lecturer at the Department of Chemistry and Applied Biosciences at ETH Zürich. He received his Ph.D. in Mechanical Engineering from the Charles III University of Madrid (Spain) and Habilitation in Analytical Chemistry at ETH Zürich. Sinues heads the Translational Breath Research group located at the University Children’s Hospital Basel.
Academic activity
Sinues has pioneered Secondary electrospray ionization with a focus in Breath gas analysis applications. He co-authored over 50 peer-reviewed articles covering fields ranging from engineering to medicine. He is President of the Society of Spanish Researchers in Switzerland (ACECH) and Vice-president of the Swiss Metabolomics Society (SMS). He also serves as an expert for InnoSuisse, the Swiss Innovation Agency
Sinues is principal investigator of the Research Network Zurich Exhalomics, which is an initiative by scientists from the Zurich area with the goal to provide technical solutions for the rapid and sensitive on-line analysis of breath. He is co-inventor of five patents and winner of the 2020 SGMS award. He co-founded the start-up company 'Deep Breath Initiative (DBI)' to uncover the full potential of Molecular Breath Analysis to advance precision medicine and make it available for general health care.
References
Outreach Activities
Martínez-Lozano et al., J Am Soc Mass Spectrom 2009, 20, 1060-63
Martinez-Lozano Sinues et al., PLoS ONE 2013, 8
BBC News
ETH news (30/1/2016)
Swiss national television (2/2/2016; in Italian)
External links
Deep Breath Initiative
Sinueslab
ACECH
Zurich Exhalomics
Year of birth missing (living people)
Living people
21st-century Spanish scientists
Mass spectrometrists | Pablo Sinues | [
"Physics",
"Chemistry"
] | 392 | [
"Biochemists",
"Mass spectrometry",
"Spectrum (physical sciences)",
"Mass spectrometrists"
] |
63,427,315 | https://en.wikipedia.org/wiki/Michael%20Bronstein | Michael Bronstein (b. 1980) is an Israeli computer scientist and entrepreneur. He is a computer science professor at the University of Oxford and scientific director of Aithyra Institute at the Vienna Biocenter in Austria.
Biography
Bronstein received his PhD from the Technion in 2007. Since 2010, he has been a professor at University of Lugano, Switzerland, affiliated with the Institute of Computational Science and IDSIA. Between 2018 and 2021, he held the Chair in Machine Learning and Pattern Recognition in the Department of Computing, Imperial College London. In 2022, he joined the Department of Computer Science at the University of Oxford as the DeepMind Professor of Artificial Intelligence.
Bronstein has held visiting appointments at Stanford University between 2009 and 2010, and at Harvard University and MIT between 2017 and 2018. He has been affiliated with the Radcliffe Institute for Advanced Study at Harvard University (as a Radcliffe fellow, 2017-2018), the Institute for Advanced Study at Technical University of Munich (as Rudolf Diesel industrial fellow, 2017-2019) and the Institute for Advanced Study in Princeton (as visitor, 2020). Since 2024, he is also an Adjunct Professor (Professeur titulaire) at EPFL.
Bronstein was a co-founder of the Israeli startup Invision, developing a coded-light 3D range sensor. The company was acquired by Intel in 2012 and has become the foundation of Intel RealSense technology. Bronstein served as Principal Engineer at Intel between 2012 and 2019, playing a leading role in the development of RealSense.
In 2018, Bronstein founded Fabula AI, a London-based startup aiming to solve the problem of online disinformation by looking at how it spreads on social networks. The company was acquired by Twitter in 2019. He served as Head of Graph Learning Research at Twitter between 2019 and 2023.
Work
Bronstein's research interests are broadly in theoretical and computational geometric methods for data analysis. His research encompasses a spectrum of applications ranging from machine learning, computer vision, and pattern recognition to geometry processing, computer graphics, and imaging. He is mainly known for his research on deformable 3D shape analysis and "geometric deep learning" (a term he coined), generalizing neural network architectures to manifolds and graphs. These methods have been applied to molecular design.
Public appearances
TEDx Warwick 2023
ICLR 2021 keynote talk
TEDx Lugano 2019 (with Kirill Veselkov)
World Economic Forum 2015.
Awards
Turing World-Leading AI Research Fellowship, 2023
Silver Medal of the Royal Academy of Engineering, 2020
Fellow of the British Computer Society
Member of the Academia Europaea, 2020
IEEE Fellow, 2019
Prix de la Fondation Dalle Molle, 2018
Royal Society Wolfson Research Merit Award, 2018
IAPR Fellow, 2018
ACM Distinguished Speaker, 2015
World Economic Forum Young Scientist, 2014
Hershel Rich Technion Innovation Award, 2003
Bronstein is also the recipient of five ERC grants, two Google Faculty Research awards, and two Amazon AWS ML Research grants.
Personal life
Bronstein is married with two children. He is the identical twin brother of Alex Bronstein.
Publications
"Numerical Geometry of Non-Rigid Shapes" (with Alex Bronstein and Ron Kimmel), Springer 2008.
"Geometric deep learning: going beyond Euclidean data" (with Yann Lecun, Joan Bruna, Arthur Szlam and Pierre Vandergheynst), IEEE Signal Processing Magazine 2017.
References
External links
Michael Bronstein's homepage at Imperial College
Living people
Israeli computer scientists
Computer vision researchers
Technion – Israel Institute of Technology alumni
Fellows of the IEEE
Fellows of the Institution of Engineering and Technology
Members of Academia Europaea
Academics of Imperial College London
Artificial intelligence researchers
Academics of the Department of Computing, Imperial College London
1980 births
Immigrants to Israel | Michael Bronstein | [
"Engineering"
] | 769 | [
"Institution of Engineering and Technology",
"Fellows of the Institution of Engineering and Technology"
] |
63,427,550 | https://en.wikipedia.org/wiki/George%20Bowes%20%28prospector%29 | George Bowes (died 1606) was an English prospector. He mined for gold in Scotland.
Family background
George was a son of Sir George Bowes of Streatlam and Dorothy Mallory. He married Magdalen Bray, daughter of Sir Edward Bray.
Coal and copper
In 1595 he planned a coal mine on his own estate of Beddick Waterville. In 1602 he was allowed to mine for copper in the Knowsley estate belonging to the Earl of Derby. At Caldbeck near Keswick, in 1602, Bowes and Francis Nedham (a son of George Nedham or Needham) reported on old copper workings and lead which contained a proportion of silver.
Surveying the gold fields in 1603
Bowes became interested in mining for gold in Scotland, probably hearing of the work of George Douglas of Parkhead and of Cornelius de Vos who had strong links with the mines in Keswick. He wrote in 1603 that James VI had invited him to come to Scotland twice before the Union of the Crowns, by means of his uncle, the ambassador Robert Bowes.
He wrote a paper describing his reasons for seeking gold on Crawford Moor. He mentioned he had worked in Cornwall, Devon, Somerset, and at Keswick. Napier of Merchiston had shown him samples of gold ore. At the request of the Privy Council, Godolphin went to Carlisle to meet Bowes and Bevis Bulmer in November 1603.
Bowes wrote to Earl of Suffolk while he was at Leadhills on 10 December 1603, describing the geology, and mentioned an earlier venture when he tried to form a partnership with Thomas Foulis, who had exclusive rights from James VI, but was discouraged by Queen Elizabeth. In another letter he described a story from an old miner's father of the discovery of a vein of gold in the time of James IV or Regent Albany, ninety years earlier, which they backfilled and hid. Bowes was understandably cautious about these stories, which came from his rival Bevis Bulmer's employees, and men who would be grateful for work in new mining ventures.
Bowes, Napier of Merchiston, Bevis Bulmer and John Brode sent a joint letter from Edinburgh on 29 December 1603 to the Privy Council. They had surveyed the gold mining region according to the king's orders given at Wilton in November. Gold had previously been found by Bulmer in the head of a long stream that descended to the Elvan water, and on Steroc brae that descends to Wanlock water, in the Glengonnar water, and the Crawick water that flows into the Nith. Although much gold had been found, no vein bearing gold had been discovered, despite finds of gold mixed with spar. The Scottish miners had not searched for veins of ore until Bulmer and Thomas Foulis had recently dug for copper. Bulmer and his workers insisted they had not found a vein. The places were remote with no dwelling places, especially for works managers, and timber for houses and lodgings would have to be brought from Leith.
Mining in 1604
He received a grant of £100 in February 1604 from the exchequer to work a mine in Scotland. Bevis Bulmer had also been given £200 in January to work gold in the same district. His letters to Robert Cecil, now Lord Essendon, complain that Thomas Foulis had disrupted his workings by detaining his English timber man. He hoped that Lord Balmerino, Secretary for Scotland would help him. Bowes stayed at Codrus Cottage, above Wanlock Water.
He wrote in March 1604 of a difficult journey in winter to the works at Wanlock Water. The Venetian ambassador Nicolò Molin reported on his progress in February 1605. He heard that Bowes had told Queen Elizabeth about gold mines in Scotland, but she had arrested him. Bowes had found support from King James and produced 25 ounces of gold but with large costs, and was losing supporters.
On 10 June 1605 he wrote to the Robert Cecil, now Earl of Salisbury, from Biddick Waterville about the progress of his search for gold in Scotland near Wanlockhead. He had requested a tent big enough to feed 80 workmen. In 1604 he had found a potential seam of spar and yellowish clay, obtaining a grant of £200 to further the work, and in November began to mine there and drain the pit. He built houses on the lands of Sir Thomas Kirkpatrick of Closeburn. He was not confident of finding gold in any quantity, and on 28 May rode to Edinburgh to report his findings to Alexander Seton, Lord Chancellor and the Lord President, Lord Balmerino. Balmerino inspected his work and the works belonging to Bevis Bulmer. Bowes abandoned his efforts in June 1605 due to poor health, and Bevis Bulmer took over his concessions. Bowes died soon after.
In July 1606 his widow, Magdalen Bowes, petitioned the Earl of Salisbury for money and help, mentioning that George Bowes had held the offices of Constable of Raby Castle and Stewardship of the lands of Charles, Earl of Westmorland. During his absence in Scotland the offices were held by William Davenport and Edward Marley who transferred to John Richardson. Bowes had to pay Richardson to get them back. Bowes had mined copper at Keswick and Knowsley in Queen Elizabeth's time, and the efforts had given him bruises and distempers which shortened his life. The Earl of Dorset had given the two offices to their eldest son, also called George Bowes, but others had made difficulties.
Stephen Atkinson, wrote that "Mr Bowes" had found a vein of gold on Wanlock Water, which Bevis Bulmer later exploited. Atkinson states this was in the reign of Queen Elizabeth. Previously gold mines had been opened by Cornelius de Vos and George Douglas of Parkhead. The British Library has a fragmentary description of gold mining in Scotland which may have been written by George Bowes as a petition for funding in 1603.
George's elder brother Robert Bowes was killed in an accident at a copper mine in Keswick in 1610.
Family
The children of George Bowes and Magdalen Bray included:
George Bowes, baptised 6 May 1596.
Robert Bowes, baptised 29 September 1597, married Joan Hutton.
Bray Bowes, baptised 2 January 1603.
Ralph Bowes
Toby Bowes of the Waterside.
William Bowes, baptised 12 August 1599.
Dorothy Bowes, baptised 7 February 1604.
Magdalen Bowes, baptised 4 February 1593.
References
1606 deaths
16th-century English businesspeople
17th-century English people
Gold mines in Scotland
Mining engineers | George Bowes (prospector) | [
"Engineering"
] | 1,354 | [
"Mining engineering",
"Mining engineers"
] |
63,428,308 | https://en.wikipedia.org/wiki/1139th%20Engineer%20Combat%20Group | The 1139th Engineer Combat Group (1139th Engr C Gp) was a technical United States Army Headquarters Unit providing administration and supervision support to Combat Engineers on bridge building and other construction activities during World War II. The 1139th Engineer Combat Group was part of the Third Army and was attached for operations to the XX Corps in direct support of the 7th Armored Division. The 1139th Engineer Combat Group fought from northern France to Austria in World War II, supporting General George Patton's Third Army's rapid movements during the war.
The 1139th Engineer Combat Group is credited with opening routes for the advancement of troops which included building 119 tactical bridges, of which 39 were 200 feet or longer, including the 1,896 foot "longest floating tactical bridge constructed in the European Theater of Operations." The Group was first formed in December 1943 and deactivated in December 1946.
Development of the Engineer Combat Group Concept
Starting with WWII, the United States Army defined a "group" to be similar in concept to a regiment, the unit type from which the group was evolved. In general, a regiment is composed of a fixed number of assigned battalions, whose personnel and equipment are likewise fixed. The battalions have only the minimum administrative personnel, with the result that administrative details are handled by the regimental headquarters. In warfare as mobile and on as vast a scale as the European campaign was, it was felt regiments were sometimes not sufficiently agile for achieving maximum effectiveness. Therefore, the group was designed as a flexible organization set up to efficiently meet rapidly changing tactical requirements. The group would consist of a small headquarters and a varying number of separate companies and battalions which could be attached to and detached from the group headquarters as the situation demanded.
The Engineer Combat Group had many duties: construction, repair and dismantling of various bridge types; clearing of obstacles; road repair and construction; ferrying troops in river crossings; laying smoke screens; detecting, removing, and laying of mines and demolitions, in addition to offensive and defensive infantry functions.
In the instance of the 1139th Engineer Combat Group, there were as many as five battalions and three separate companies under their command at one time, and at other times the group headquarters controlled as little as a single company. The job of the 1139th was twofold. Primarily, they were responsible for the administration of the units under their command, and secondarily, they acted in a supervisory capacity for all work assigned to the group. In addition to the combat engineer battalions, the group could have separate battalions and companies that specialized in constructing specific types of bridges such as heavy and light pontoon bridges, treadway bridges, Bailey bridges, or other specialized support functions such as area lighting or smoke generation. The units under control of the group headquarters were used to support divisions' engineer operations, providing special equipment which the division engineers did not carry, and augmenting the engineer personnel strength of the divisions' engineer battalions.
1139th Engineer Combat Group Training and Deployment
The 1139th Engineer Combat Group was activated on August 25, 1943, at Camp Beale, California. Many of the troops that would eventually make up the 1139th Engineer Combat Group received their initial training at Camp Ellis, Illinois, an Army Services Training Center for the Corps of Engineers located southwest of Peoria, Illinois. Most were not career soldiers, and were consigned to "the duration plus six months" of service. From there they were sent to Camp Beale, California, to join the 1139th and complete training as a unit. In addition to their basic training courses, the men of the 1139th received courses in camouflage, mine field clearing, mapping, reconnaissance, bridge building, and road construction. The 1139th was commanded by Colonel John S. Niles, with Lt. Colonel George H. Walker as the executive officer.
On July 1, 1944, the 1139th Engineer Combat Group, consisting of 16 officers and 66 enlisted men, left Camp Shanks by train to the New York Port of Embarkation and began loading on to the USAT Thomas H. Barry. Early the next morning the ship joined a convoy heading to Scotland. They arrived at the town of Greenock, Firth of Clyde, Scotland on July 12, 1944. The next day they disembarked and traveled via a twelve-hour train trip to Doddington, Nantwich, England, where they organized their men and supplies, and drew vehicles, trailers and other T/E equipment (equipment specified for their specific operations) as required.
On August 1, 1944, they traveled via truck convoy from Doddington to Bournemouth, England; a large troop marshaling area in preparation of movement to Continental Europe. On August 5, 1944, they left England sailing on the USAT George Custer and arrived on Utah Beach just two months after the D-Day landings there. Over the next two days, the unit disembarked and bivouacked in the Utah Beach area.
The 1139th in the European Theater of Operations
On August 8, 1944, they proceeded in motor convoy across the Cherbourg Peninsula moving north to Bricquebec, France, and at that point they began to work as an operational unit taking its position in the line of advance, with the First Army on its left flank and the XII Corps on the right flank. The 1139th Engineer Combat Group was assigned to the Third Army and attached for operations to the XX Corps in direct support of the 7th Armored Division. (When a unit is "assigned", it becomes a permanent part of the headquarters to which it is assigned. When the unit is "attached", it comes under the administrative and operational control of that unit to which it is attached.)
It was at that point that their executive officer, Lt. Col. George H. Walker, outlined their responsibilities; as part of General Patton's army the mission of the 1139th Engineer Combat Group was to travel directly behind the armor and remove mines, build bridges, fight as infantry and perform other engineering activities that allowed the rapid advancement of the XX Corps. (The XX Corps played a measurable role in Patton's dash across France in August and early September 1944, earning the nickname "Ghost Corps" for the speed of its advance; starting in Bricquebec, France, they traveled 600 miles in their first 30 days). The XX Corps armored divisions typically traveled many miles ahead of the main body of the army, which resulted in many enemy positions being overrun before alarm could be given.
The 1139th Engineer Combat Group arrived in the vicinity of Saint Jean sur Erve, France, on August 10, 1944, and was joined by their first battalions; the 135th, the 179th, and the 206th Engineer Combat Battalions. The initial activity of the Group was to support the 80th Infantry Division in its thrust north against the enemy near Sainte-Suzanne, France.
On August 13, 1944, while en route during this advance, the Group removed landmines from roads and shoulders, and the first of the 1139th's bridges were constructed; two 60 foot Bailey Bridges built at St. Mars and St. George, France, on the sites of two bridges that had been blown up by the enemy. (A Bailey Bridge is a temporary pre-fabricated, truss bridge, quickly assembled from prefabricated, standardized parts, assembled on land and then launched across an opening). Two days later they constructed two Treadway Bridges M2 across the Huisne River at La Ferté-Bernard, and at Nogent-le-Rotrou, France. (A Treadway Bridge is a floating bridge, using pontoons to support a continuous deck for pedestrian and vehicle travel). In his European campaign, General Eisenhower recognized that the Treadway bridge was an essential piece of equipment to the campaign, easy to transport, quickly installed, and capable of sustaining heavy military loads.
On August 17, 1944, the 1139th meet stiff resistance as they were trying to enter Chartres, France, requiring the 1139th Engineer Combat Group to take on their infantry role. They engaged in firefight operations by cleaning out machine-gun and anti-tank gun nests in Bonville, France, suffering 6 dead and 12 wounded. They constructed two short Treadway bridges at Luce, France, west of Chartres and removed twelve large bombs from bridges in Chartres. By the next day they were joined by the 7th Armored Division, and the city was finally liberated.
The Group then moved north to the vicinity of Treon, France, in support of the 7th Armored Division. There they were tasked with clearing the roads of mines, removing booby-trapped vehicles from roads, de-booby-trapping the Railroad station at Dreux, France, and filling in road craters in the routes of the advancement. They continued to move rapidly forward, and the Seine River was reached on August 23, 1944, where they bivouacked in an open field near Melun, France. At Sainte Sauveur, France, the 1139th Engineer Combat Group supported the 7th Armored Division in its initial crossing of the Seine River at Tilly, France by manning assault boats, by establishing a beachhead and constructing a 504-foot Treadway Bridge while under direct fire, and by constructing a 204-foot footbridge across the canal at Melun, France. The construction of the foot-bridge was carried on under heavy small arms and 88mm fire. An 88mm shell blew out 50 feet of the bridge during construction, which had to be replaced while under intense enemy fire.
Over the next few days, the Seine was bridged in three more places by the 991st and the 994th Engineer Treadway Bridge Companies, the 537th Engineer Light Ponton Company, and the 135th, 179th, and 206th Engineer Combat Battalions. These crossings consisted of multiple span continuous Bailey bridges, a 210-foot Bailey at Vulaines-sur-Seine, Frances, and a 420-foot Bailey at Champagne, France. Most of the construction was carried out at night, and took place under enemy fire, resulting in several lives lost. When the bridges were completed, they were guarded and maintained while under considerable fire.
Arriving at Montmiral, France on August 28, 1944, the 1139th Engineer Combat Group underwent a leadership change with executive officer Lt. Col. Walker leaving to become the commanding officer of the 1103rd Engineer Combat Group, and Lt. Col Robert Eininger replacing him.
The next major objective of the Third Army was Verdun, France and the Moselle Valley, which offered a natural gap in Germany's frontier line. Early in the morning of September 2, 1944, the XX Corps arrived 5 miles west of Verdun. Within a matter of hours, the city fell to the armored division, and on September 4, 1944, the 509th Engineer Light Ponton Company had built a 200-foot Baily bridge over the Meuse River and a bridgehead was established on the eastern side of the river. At this point, the Third Army's Armored Divisions had outpaced the Redball gasoline supply column, and although emergency supply convoys were rushed south, the Germans had time to reinforce their positions at Metz, Germany. The American bridgehead had to be withdrawn from across the Meuse. While awaiting gasoline reinforcements the 1139th Engineer Combat Group completed a considerable amount of repair on the railroads in the vicinity. Repairs were made by filling in bomb craters in the yards east of Verdun, and by rehabilitation of the track and roadbed from Conflans to Verdun, France, including construction of a 280-foot single track bridge at Conflans.
On September 15, 1944, when adequate supplies had finally reached the Third Army, they moved on toward Thiacourt, France. The 135th Engineer Combat Battalion working with the 180th Engineer Heavy Ponton Battalion constructed a 260-foot Heavy Pontoon bridge at Pagny, France. Because of a shortage of Engineer troops, it was necessary to form a provisional platoon from the Group Headquarters Company to assist in the construction. Then working with the 509th Engineer Light Ponton Company, they constructed two 80 foot Bailey bridges across the Moselle River. The bridge building units worked under constant heavy mortar and artillery fire at these crossings, but were aided by the 161st Chemical Smoke Generating Company laying down a heavy smoke screen from hundreds of smoke generators and pots. The cost in lives was high, but it helped pave the way towards taking the heavily defended city of Metz. Despite the pressure of the continued rapid advance of the Group, morale among the troops remained at a high level.
During the month of October 1944, the 1139th Engineer Combat Group grew to one of the largest tactical engineer groups in the United States Army. Over 5000 troops were under their command, including the 5th, 83rd, 90th, and 95th Infantry Divisions, the 179th and 206th Engineer Combat Battalions, the 991st Engineer Treadway Company, the 509th Engineer Light Ponton Company, and the 623rd Engineer Light Equipment Company. This concentration of men and equipment was in preparation of supporting the crossing of the Moselle River by the 10th Armored Division and the 90th and 95th Infantry Divisions. In preparation for this, the troops were instructed in crossing techniques using Assault Boats, and the Group experimented with building a rapid bridge-launching-device constructed on a tank frame. (While functional, this vehicle was unfortunately found to be so heavy that it was not practical to move for any real distance).
The month of November 1944, was of extreme importance to the XX Corps because the crossing of the Moselle River and advancement eastward depended upon the success by the 1139th Engineer Combat Group in bridging the River. Eight bridges were constructed across the Moselle River by the 1139th Engineer Combat Group during the month; two Treadway M2s of 350 and 396 feet in length, one 630 foot Treadway M1, two Floating Baileys of 530 and 440 feet in length, one Baily DS, and two Heavy Pontoon bridges of 730 and 675 feet in length. These crossings were unusually difficult because the Moselle River was in a state of 30-year flood, and the enemy was continually making the bridging difficult with heavy artillery, machine gun and small arms fire. The enemy fire at Cattenom, France, was so intense that the 440 foot Floating Bailey Bridge was eventually lost. In most of these crossings the engineers had to first resort to ferrying operations in order for the infantry to clear a beachhead on the eastern shore so that the bridges could be constructed. Numerous troop losses occurred during these crossings.
After the successful crossing of the Moselle River by the 90th and 95th Infantry Divisions and the 10th Armored Division, studies of aerial photographs revealed the need for all the engineers in the Group to help overcome the obstacles left by the enemy; extensive antitank ditches, craters, pill boxes, blown bridges, and numerous mine fields (one minefield alone was estimated to contain 10,000 mines). The burden of this work was so great that the 135th Engineer Combat Battalion was reattached to the 1139th Engineer Combat Group for the purpose of taking over the work in the rear of the division, including filling craters and ditches, destroying pill boxes, constructing fords, marking minefields, posting road signs, changing town signs, and removing the dead to Graves Registration. Because of the large number of bridges under construction during November, it was also necessary to utilize the 88th Engineer Heavy Ponton Bridge Battalion to haul Bailey bridges from Army Supply Point No. 8 to Thionville, France, and to maintain the Group Bridge Dump there.
In December 1944, while planning the crossing of the Saar River, the 1139th Engineer Combat Group was stationed at Niedaltdorf, France. On December 6, 1944, the 90th Infantry Division, located near Wallerfangen, France, was ready to make the assault crossing. The 20th Engineer Combat Battalion began ferrying operations in Assault and storm boats. They ferried across two Battalions and part of a third battalion of the 38th Infantry Regiment, while the 179th Engineer Combat Battalion ferried the 1st and 2nd Battalions of the 357th Infantry Regiment. Following these operations the storm boats continued to evacuate wounded and to deliver supplies. Although all operations of the river were carried out under continuous heavy artillery and small arms fire day and night, there was no letup in the steady flow of materials and supplies by the storm boats. However, the incoming fire was so heavy that power boats could not be brought down to the river for launching.
After several unsuccessful attempts, a ferry was constructed on December 8, 1944, for ferrying vehicles, anti-tank guns and tanks across the river at Wallerfangen, with additional ferries at Pachten-Dillingen and Rehlingen-Siersburg, France, which made it possible to ferry all the vehicles and tanks of the 90th Infantry as rapidly as they were needed to secure a beachhead on the eastern shore. This was of importance since a floating bridge was not able to be constructed, since sections were shot away as rapidly as they were placed into the water. The Saar across from Dillingen, Germany, continued to prove difficult to cross because of heavy fire from a large number of occupied German pill boxes on the eastern side of the river where the Siegfried Line had been most heavily constructed. As a result, a bridgehead was not expanded there to any great depth, although ferrying operations continued until December 20, 1944.
These activities were interrupted as Germany made its last major offensive campaign; the Battle of the Bulge (also known as the Ardennes Counteroffensive). When General Patton learned of the attack, he quickly repositioned six full divisions of his army from their locations along the Saar River to launch a counterattack north to relieve the U.S. 101st Airborne Division which had been trapped at Bastogne. To replace the repositioned defensive divisions along the Saar River, the 90th Infantry Division withdrew from their eastern beachhead at Dillengen to join the 95th Infantry Division in defending the western side of the River. The 1139th Engineer Combat Group supported both divisions in constructing defensive barriers consisting of mine fields, roadblocks, and bridges prepared for demolition, as well as guarding many of these deterrents.
During January 1945, the 1139th Engineer Combat Group continued to support defensive operations on the west bank of the Saar River, consisting of barrier zone and roadwork maintenance, installation of an anti-mine boom at Maimühle, Germany, roadway snow-plowing and sanding, guarding displaced German citizens at Niedaltdorf, removing mines and booby traps at Thionville, and patrolling the banks of the Moselle River.
By February, the Germans were in full retreat from the Ardennes. During the first three weeks of February 1945, the 1139th Engineer Combat Group was engaged in miscellaneous engineer activities in support of the 94th Infantry Division and the 3rd Cavalry Regiment. Because of sudden thaws supplemented by heavy rains, the Moselle River was swollen to flood heights again. As a result, great ice floes were swept down the river with such force that it necessitated the removal of all floating bridges. The salvaged materials were removed and placed in the storage dumps, and as soon as possible the bridges were reconstructed to allow traffic over the Moselle again. On February 20, 1945, the 1139th Engineer Combat Group was given the mission of assisting the 94th Infantry Division in its assault crossing of the Saar River. Under heavy enemy fire coming from strategically located pill boxes on the east bank, three successful assault crossings were made between the 21st and 23 February at Taben, Serrig, and Ayl, Germany.
The first bridge crossings of the Saar River under the direction of the 1139th occurred February 24 and 26, 1945. The 135th Engineer Combat Battalion installed a 240-foot Treadway bridge at Taben, Germany, and a 286' Heavy Pontoon Bridge at Saarburg, Germany, and the 993rd Engineers Treadway Bridge Company built a 320-foot Treadway Bridge at Serrig, allowing the 94th Infantry Division to cross the Saar River and established a vital bridgehead at Serrig, Germany. This, in turn, allowed a 286-foot Heavy Pontoon bridge and a 336-foot Treadway bridge to be built across the Sarr at Niederleuken and Schoden, Germany, so that both Infantry and Armor could cross and reduce the enemy on the eastern side of the Saar. On March 6, 1945, an additional 336-foot Treadway M2 C1 bridge was then established at Konz Karthaus, Germany by the 179th and the 206th Engineer Combat Battalions.
During the first part of March 1945, the 1139th Group was engaged in engineering work necessary for the rapid advancement of the XX Corps from the Saar to the Rhine Rivers. In addition to construction of many Bailey Bridges and small fixed bridges, they were tasked with supervising civilian labor on road work, preparing gun emplacements for artillery pieces, constructing camouflage screens and anti-mine booms at bridges, removing dead animals from minefields, hauling prisoners, demolishing buildings to widen roads, painting town signs, and destroying enemy tanks and artillery pieces.
In quick secession the American Armies were converging on the enemy in the Rhine-Moselle triangle; the 4th Armored Division from the North, the 10th and 6th Armored Divisions from the South, and the 3rd and the 7th Armies from various locations. Lieutenant Colonel Omar Bradley told General George S. Patton, whose U.S. Third Army had been fighting through the Palatinate to "take the Rhine on the run." The Third Army did just that on the night of March 22, 1945, crossing the river with a hasty assault south of Mainz at Oppenheim by the 17th Armored Engineer Battalion on a 1,152 foot long Treadway M2 Bridge. It was there on March 24, 1945, that Patton showing his contempt for the enemy, made good on his pledge to "piss in the Rhine", which he did from a pontoon bridge in full view of his men and news cameras.
Then on March 25, 1945, while in the area of Ober-Hilbersheim, Germany, the 1139th received orders to make a major river crossing over the Rhine River at Mainz, Germany. Extensive studies were made by the 1139th Engineer Combat Group to determine the best site for crossing. Study of all available maps and photos determined that the downtown area of Mainz, Germany, was the best site, even though the Rhine was wider at that point. Profiles were prepared for the entire area, showing which terrain areas had to be captured or neutralized by artillery fire, and hydraulic data and river bed materials were studied to understand the types and sizes of anchors necessary for the bridge. Finally, site reconnaissance at the river's edge by Group personnel determined the exact location for the bridge. This crossing required two assault operations led by the 80th Infantry Division with support from the 135th Engineer Combat Battalion.
The first infantry crossing (using assault boats) incurred a high casualty rate, so the two battalions were then crossed by the 1139th Engineer Combat Group supported Naval units. Once the infantry was ashore, ferrying operations were carried on by Navy operated boats, using 6 LCMs and 6 Higgens Boats. During the launching there was heavy artillery fire, 20mm and small arms fire on the site, knocking out a bulldozer and killing a naval officer. However, the 997th Engineer Treadway Company with assistance from the 160th Engineer Combat Battalion was able to construct a Treadway M2 Bridge across the Rhine 1,896 feet long; the Longest Tactical Bridge built in the European Theater of Operations. This bridge served the entire XX Corps in crossing the Rhine and marked the end of the assault phase of the Rhine in the Third Army area.
Once across the Rhine, they found the enemy largely routed and in full retreat. On March 31, 1945, the Third Army started its run towards Berlin, from Mainz, Germany, traveling north-east through Frankfurt to Friedberg, to Alsfeld, then crossing the Fulda River with a 312-foot Treadway M2 Bridge, on to Reichensachsen, Germany. Then traveling eastward they next bridged the Werra River and traveled to Langensalza, Germany, and after bridging the Helme River on April 11, 1945, they traveled along the Autobahn for two days constructing Bailey Bridges where needed to repair sections of the highway that had been destroyed by allied bombardment. While traveling the Autobahn, they came across an area where the median strip had been paved as a landing airstrip and painted green, and on it sat an unusual-looking plane with no propeller. It turned out to be one of the German Jet planes that had been abandoned during the rapid retreat of the German Army.
The 1139th stopped in Weimar, Germany, on April 13, 1945. Here they were situated in the most luxurious barracks that they had stayed in; formerly used by German Anti-aircraft troops. However, it was also here that they saw their most horrible of all sights; the Buchenwald Concentration Camp. The Third Army had liberated the camp just two days earlier. At the urging of General Patton, many of the 1139th troops visited the camp and saw the walking skeletons, stacks of withered corpses, and incompletely burned bodies, pits of lime covered bodies, and all saw emaciated inmates from the camp walking along the road towards Weimer, and heard firsthand accounts about the horrors from a former Captain of the Dutch army, who was taken in from the camp to act as an interpreter.
On April 16, 1945, the Third army continued moving eastward until it arrived just outside of Chemnitz, Germany. At this point, they were only 135 miles from Berlin. However, with the threat of a National Redoubt (potential reorganization and resistance by the remainder of the German army), Eisenhower ordered Patton's army southward toward Bavaria and Czechoslovakia, anticipating a last stand there by Nazi German forces. The XX Corps raced south-westward to Lichtenfels, Germany; bridging the Saale and the Weisse rivers, arriving April 18, 1945. Then turning southeast they bridged the Main River and traveled to Pegnitz, Germany, and after spanning the Naab River with a 240-foot Treadway M2 Bridge arrived in Burglengenfeld, Germany on April 25, 1945. On April 27, 1945, they traveled to Regensburg where they stopped to develop plans for crossing the Danube River. Then continuing into southern Bavaria, they constructed a 516-foot Treadway M2 Bridge to cross the Danube, arriving in Straubing, Germany on April 30, 1945.
On May 2, 1945, they left Straubing and constructed a 288-foot Treadway M2 bridge to cross the Isar River at Landau an der Isar, Germany, and arrived in Ortenburg on May 3, 1945. On May 4, 1945, the 1139th constructed a 560-foot Heavy Pontoon Bridge over the Inn River at Passau, Germany, and the next day they left Ortenburg, Germany and moved southeastward to Lambach, Austria, where contact was made with the Russian forces.
This was the furthest they traveled in search for the National Redoubt by the German Army. It was here, on May 7, 1945, that the troops heard that finally Germany would officially surrender the next day. The same day General Walton H. Walker, commander of the XX Corps, received the unconditional surrender of Generaloberst Lothar Rendulic, commander of German Army Group South.
The 1139th constructed a 516-foot Treadway M2 Bridge across the Isar River at Plattling, Austria, and on May 9, 1945, they constructed their final bridge, a 755-foot Heavy Pontoon Bridge over the Inn River at Schaerding, Austria. On May 10, 1945, the 1139th left Lambach, Austria and began their return home moving north-eastward to Ried im Innkreis, Austria.
The 1139th as part of the Army of Occupation in Germany
After VE Day, the 1139th was involved in assisting the German people rebuild their state as part of the U.S. Army of Occupation in Germany. Initially, the 1139th Engineer Combat Group expected to be broken up following VE Day, with some troops destined for the Pacific, while others moved to fill in personnel gaps in other units.
However, General Eisenhower felt that rehabilitation of the Ruhr area in Germany was vital to rebuilding the German economy, because nowhere else in Europe were there coal deposits of that quality and ease of access. This coal was key to allowing Germany to rebuild its industries and in turn to feed its own population.
Colonel Niles and the 1139th Engineer Combat Group were given this duty. The 1139th was assigned to get the Bavarian and Saar coal mines back in operation. This included clearing and preparing the mine sites for return to operations, and because there were few returning coal miners, the 1139th's Engineers were also required to providing training and education to the surviving populous on running the mine. The 1139th worked on the mine projects for many months. During these activities the 1139th was experiencing a slow reduction in troop size as the GIs with 45 VE Day points or more were discharged and returned home to the states.
The 1139th Engineer Combat Group returned to the United States at Boston, Massachusetts on October 26, 1945, and was inactivated the next day at Camp Myles Standish, Massachusetts.
Tables and Documents
Table 1: Divisions and Regiments that were supported by the 1139th Engineer Combat Group
Table 2: Battalions and Companies that were attached to the 1139th Engineer Combat Group
Table 3: Bridges Constructed by the 1139th Engineer Combat Group
Table 4: Awards received by soldiers of the 1139th Engineer Combat Group
External links
Liberty Ships built by the United States Maritime Commission in World War II (includes USAT #0646 George A. Custer)
History of Doddington Park, UK 1946-1960
Patton's 3rd Army, advance to Moselle Valley, at Verdun during WW2, Sept 2 1944
Further reading
Notes and References
20
Combat
Explosives engineers
Military units and formations established in 1943 | 1139th Engineer Combat Group | [
"Engineering"
] | 6,169 | [
"Explosives engineering",
"Explosives engineers"
] |
63,428,618 | https://en.wikipedia.org/wiki/Cummins%20Quantum%20Series | Cummins Quantum Series is a family of internal combustion engines, developed and manufactured by American Cummins for various heavy-duty use cases. The Quantum series comes with an electronic controlled module. It is used in heavy duty machines and in railway machines.
Current types
The lineup consists of adaptations of F, B, L, X series and Quantum-only K series. There are also G12 and T30 engines in the lineup.
Diesel engines
Vast majority of Quantum series engines are Diesel engines. Those are compared in the table below:
Gas engines
Natural gas engines also exist.
Notes
References
Cummins diesel engines | Cummins Quantum Series | [
"Engineering"
] | 121 | [
"Mechanical engineering stubs",
"Mechanical engineering"
] |
63,429,645 | https://en.wikipedia.org/wiki/Monumentalism | Monumentalism defines the architectural tendencies that during the first half of the twentieth century had as their essential canon the inspiration and connection to classicism and neoclassicism. Critics divide this architecture into two streams: Neo-Baroque and Simplified Neoclassicism.
Neo-Baroque
Neo-Baroque (Baroque Revival) shows a return to the eighteenth century with the proportion of orders becoming gigantic, enriched with ornamental friezes. It is the public architecture of the Soviet Union with the various buildings of the central party committees in Leningrad as in Kiev. The scenographic vision of the architectural space, which is to celebrate the regime, takes over on the planimetric composition of the buildings.
Simplified Neoclassicism
Simplified Neoclassicism, also called Novecento Italiano style, is linked to the classical architectural culture, but lightens its elements and architectural details, removing or simplifying the decoration. This is the architecture preferred by totalitarian regimes for its celebratory efficacy in the built environment, with the exaltation of the Roman age in the Italian case. Its major theorist will be in Italy the architect Marcello Piacentini who dominates the fascist twenty years with his canons, crowding out the rationalists, who attempted to reconcile the themes of the Modern Movement within an authoritarian regime. This style also affected new urbanistic projects (university city of Rome, E42) and the demolition and reconstruction of historic centers (Via della Conciliazione, historic centers of Brescia and Livorno).
Piacentini will develop two essential canons: the exterior modernization of the style and the classic structure of the architectural design, with:
the elementaryization of the architectural details; smooth walls, full balconies, flattened frames, lightened capitals, elementary arches, beveled columns, which must remind the Mediterranean Sea and past "Roman times", also adopting specific materials such as marble;
an empty neoclassical architectural space with symmetrical and blocked plans, closed volumes, gigantism of proportions, exaltation of the overall scenographic vision.
Links with the Modern Movement
Some scholars identify traits that of the Novecento Italiano in architects who straddle the nineteenth-century language and the Modern Movement, as in the last works of Auguste Perret, where the features are however much more sober and somehow refer to the classical French tradition, as in the Public Works Museum of 1937. Other examples are found in the so-called Scandinavian Classicism and with some constructions by the Swedish architect Gunnar Asplund, who for some in the Stockholm Crematorium 1935–40 achieves a balance between modern forms and monumentalism in an ideal of synthesis with the languages of the past classical tradition.
Some include in monumentalism, even if in part, the so-called metaphysical architecture of interwar Italy, typical of which some fascist-era cities of foundation such as Portolago (on the Greek island of Leros) or Sabaudia. This, however, seems more related to the themes of the Modern Movement in its specification and Italian characteristic (Italian Rationalism), defining the two cities described above as rare examples, although unknown as regards the first, of the International Style.
Some critics go even further, including in Monumentalism part of some architectural expressions of the Modern Movement, when they concerned a search for symmetry, perfect, repetitive and monumental rhythm, as in the works of Mies van der Rohe, of which the Seagram Building it is the most complete expression. Also in some works by Giuseppe Terragni the primordial forms of Monumentalism such as the cubic, monolithic and strongly symbolic volumes are found. Moreover, the Casa del Fascio of Como, one of the masterpieces of Italian Rationalism, is designed on the golden section and built on symmetrical balances. However, these buildings belonging to the Modern Movement have different articulations in plan in relation to the functional distribution, which is less found in decidedly monumental constructions; in them the architectural space is closely linked to the relationship between form and function, which is the first and essential characteristic of the rationalistic theme.
Related pages
Fascist architecture
Stripped Classicism
Architectural history | Monumentalism | [
"Engineering"
] | 841 | [
"Architectural history",
"Architecture"
] |
63,430,208 | https://en.wikipedia.org/wiki/Nokia%205310%20%282020%29 | The Nokia 5310 (2020) is a Nokia-branded feature phone developed by HMD Global. It was announced on 19 March 2020 alongside the Nokia 1.3, Nokia 5.3 and Nokia 8.3 5G, as a revival of the original Nokia 5310 produced .
Functions and design
The 5310 functions primarily as a media-player with FM-radio, an MP3-player, support for Bluetooth 3.0 and front-facing stereo-speakers. A 3.5 mm audio jack is also present, and dedicated music buttons are located on the side. The phone has a 2.4" QVGA resolution display. On the rear, there is a VGA camera accompanied by an LED-flash. Internal storage is limited to 16 MB, but can be expanded up to 32 GB via a microSD card slot. The battery is rated at 1200 mAh and can provide 7.5 hours of talk time; standby ranges between 30 days for Single-SIM and 22 days for Dual-SIM. The device only supports dual-band 2G.
The design is styled after the original 5310 with the same color-schemes, Black/Red and White/Red.
2024 version
In April 2024, HMD Global announced the 2024 version of revival Nokia 5310, with design similar to the 2020 version, but with some improvements, like a larger screen at 2.8 inches IPS LCD (compared to the 2.4-inch TFT LCD of the 2020 version), bigger 1450 mAh battery (compared to the 1200 mAh battery), Unisoc 6531F chipset (compared to the MediaTek MT6260A chipset) and USB-C support (compared to the micro USB 1.1 support).
References
External links
5310
Nokia phones by series
Mobile phones introduced in 2020
Mobile phones with user-replaceable battery | Nokia 5310 (2020) | [
"Technology"
] | 385 | [
"Mobile technology stubs",
"Mobile phone stubs"
] |
63,430,814 | https://en.wikipedia.org/wiki/L-163%2C491 | L-163,491 is an experimental drug which acts as a partial agonist of angiotensin II receptor type 1, and with lower affinity as an agonist of angiotensin II receptor type 2, mimicking the action of angiotensin II. Its practical applications to date have been limited to scientific research into the function of the angiotensin receptor system, but it has been suggested as a potential therapeutic agent for the treatment of inflammation of the lungs associated with certain viral diseases such as COVID-19.
References
Agents acting on the renin-angiotensin system
Experimental drugs
Imidazopyridines | L-163,491 | [
"Chemistry"
] | 132 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
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63,430,824 | https://en.wikipedia.org/wiki/COVID-19%20drug%20repurposing%20research | Drug repositioning (also known as drug repurposing, re-profiling, re-tasking, or therapeutic switching) is the repurposing of an approved drug for the treatment of a different disease or medical condition than that for which it was originally developed. This is one line of scientific research which is being pursued to develop safe and effective COVID-19 treatments. Other research directions include the development of a COVID-19 vaccine and convalescent plasma transfusion.
Several existing antiviral medications, previously developed or used as treatments for severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), HIV/AIDS, and malaria, have been researched as potential COVID-19 treatments, with some moving into clinical trials.
In a statement to the journal Nature Biotechnology in February 2020, US National Institutes of Health Viral Ecology Unit chief Vincent Munster said, "The general genomic layout and the general replication kinetics and the biology of the MERS, SARS and [SARS-CoV-2] viruses are very similar, so testing drugs which target relatively generic parts of these coronaviruses is a logical step".
Background
Outbreaks of novel emerging infections such as COVID-19 pose unique challenges to discover treatments appropriate for clinical use, given the small amount of time available for drug discovery. Since the process of developing and licensing a new drug for COVID-19 was expected to pose a particularly long delay, researchers have been probing the existing compendium of approved antivirals and other drugs as a cost-effective strategy in the meantime. In early 2020 hundreds of hospitals and universities began their own trials of existing safe drugs with repurposing potential against COVID-19.
Drug repurposing usually requires three steps before taking the drug across the development pipeline: recognition of the right drug; systematic evaluation of the drug effect in clinical models; and estimation of usefulness in phase II clinical trials.
One approach used in repositioning is to look for drugs that act through virus-related targets such as the RNA genome (i.e. remdesivir). Another approach concerns drugs acting through polypeptide packing (i.e. lopinavir).
The rush to publish papers about the pandemic resulted in some scandals of inaccurate scientific publications. Some early studies reporting the efficacy of hydroxychloroquine and remdesivir convinced drug agencies such as Food and Drug Administration (FDA) and European Medicines Agency to approve the off-label use by issuing Emergency Use Authorizations which were later revoked as new evidence showed these drugs have no effect on the course of COVID-19. These false-positive results can be explained in terms of the base-rate fallacy and the rapid changes in clinical guidance regarding COVID-19 treatment could have been avoided if mechanistic evidence for and against repurposing candidates were carefully assessed and the standard evidence amalgamation tools such as meta-analysis were routinely applied.
Monoclonal antibodies
Monoclonal antibodies under investigation for repurposing include anti-IL-6 agents (tocilizumab) and anti-IL-8 (BMS-986253). (This is in parallel to novel monoclonal antibody drugs developed specifically for COVID-19.)
Mavrilimumab is a human monoclonal antibody that inhibits human granulocyte macrophage colony-stimulating factor receptor (GM-CSF-R). It has been studied to see if it can improve the prognosis for patients with COVID-19 pneumonia and systemic hyperinflammation. One small study indicated some beneficial effects of treatment with mavrilimumab compared with those who were not.
In January 2021, the UK National Health Service issued guidance that the immune modulating drugs tocilizumab and sarilumab were beneficial when given promptly to people with COVID-19 admitted to intensive care, following research which found a reduction in the risk of death by 24%.
Tocilizumab
Anticoagulants
Medications to prevent blood clotting have been suggested for treatment, and anticoagulant therapy with low-molecular-weight heparin appears to be associated with better outcomes in severe COVID-19 showing signs of coagulopathy (elevated D-dimer). Several anticoagulants have been tested in Italy, with low-molecular-weight heparin being widely used to treat patients, prompting the Italian Medicines Agency to publish guidelines on its use.
Scientists have identified an ability of heparin to bind to the spike protein of the SARS-CoV-2 virus, neutralising it, and proposed the drug as a possible antiviral.
A multicenter study on 300 patients researching the use of enoxaparin sodium at prophylaxis and therapeutic dosages was announced in Italy on 14 April.
The anticoagulant dipyridamole is proposed as a treatment for COVID-19, and a clinical trial is underway.
Antidepressants
Many antidepressants have anti-inflammatory properties. An observational study in Paris area hospitals found that COVID-19 patients admitted to the hospital who were already taking an antidepressant had 44% less risk of intubation or death. The potential mechanisms how fluvoxamine and fluoxetin are contributing to prevent the development of severe respiratory symptoms of COVID-19 by protecting the type 2 lung alveolar cells have been summarized in a review in March 2022.
Fluvoxamine
In October 2021, the TOGETHER trial, a large clinical trial in Brazil, reported that treating high-risk outpatients with an early diagnosis of COVID-19 with 100 mg fluvoxamine twice daily for 10 days reduced by up to about 65% the risk of hospitalization. The effect was reduced to about 32% with low adherence, possibly due to intolerance. There was also a reduction in the number of deaths by up to about 90% with high adherence. The drug was studied because of its anti-inflammatory effects, but the mechanism of action against COVID-19 remains uncertain.
On 16 December, the NIH found that use of fluvoxamine did not impact incidence of covid-related hospitalizations and considered the evidence insufficient to recommend either for or against the drug.
On 23 December, under very low certainty evidence, the Ontario clinical practice guideline suggested considering the drug to treat mildly ill patients within 7 days of symptom onset.
In May 2022, based on a review of available scientific evidence, the US Food and Drug Administration (FDA) declined a request to issue an Emergency Use Authorization (EUA) for fluvoxamine to treat COVID-19, saying that the data were not sufficient to conclude that it may be effective in treating non-hospitalized people with COVID-19 to prevent serious illness or hospitalization. University of Minnesota professor David Boulware, who filed the EUA application, said that the standard that they were holding for fluvoxamine was a different standard than the other big pharma trials, with Paxlovid and molnupiravir and the monoclonals.
Antioxidants
Acetylcysteine (NAC)
Acetylcysteine is being considered as a possible treatment for COVID-19.
Antiparasitics
The idea of repurposing host-directed drugs for antiviral therapy has experienced a renaissance. In some cases the research has highlighted fundamental limitations to their use for the treatment of acute RNA virus infections. Antiparasitics that have been investigated include chloroquine, hydroxychloroquine, mefloquine, ivermectin, and atovaquone.
Chloroquine and hydroxychloroquine
Ivermectin
Antivirals
Research is focused on repurposing approved antiviral drugs that have been previously developed against other viruses, such as MERS-CoV, SARS-CoV, and West Nile virus. These include favipiravir, remdesivir, ribavirin, triazavirin, and umifenovir.
The combination of artesunate/pyronaridine was found to have an inhibitory effect on SARS-CoV-2 in vitro tests using Hela cells. Artesunate/pyronaridine showed a virus titer inhibition rate of 99% or more after 24 hours, while cytotoxicity was also reduced. A preprint published in July 2020, reported that pyronaridine and artesunate exhibit antiviral activity against SARS-CoV-2 and influenza viruses using human lung epithelial (Calu-3) cells. It is in phase II clinical trial in South Korea and in South Africa.
Molnupiravir is a drug developed to treat influenza. It is in Phase III trials as a treatment for COVID-19. In December 2020, scientists reported that the antiviral drug molnupiravir developed for the treatment of influenza can completely suppress SARS-CoV-2 transmission within 24 hours in ferrets whose COVID-19 transmission they find to closely resemble SARS-CoV-2 spread in human young-adult populations. A clinical trial, which has not as of 1 October 2021 been peer reviewed, suggests molnupiravir taken orally can reduce the risk of hospitalization and prevent death in patients diagnosed with COVID-19. The drug needs to be given early to be effective. As of 1 January 2022, Molnupiravir has been approved for emergency use against COVID-19 in the United Kingdom, India, and the United States.
Niclosamide was identified as a candidate antiviral in an in vitro drug screening assay done in South Korea.
Protease inhibitors, which specifically target the protease 3CLpro, are being researched and developed in the laboratory such as CLpro-1, GC376, and Rupintrivir.
Coronaviruses species possess an intrinsic resistance to ribavirin.
Sofosbuvir/daclatasvir is a drug combination developed to treat hepatitis C. In October 2020, a meta-analysis found a significantly lower risk of all-cause mortality with the drug combination when given to hospitalized patients.
Favipiravir
Favipiravir is an antiviral drug approved for the treatment of influenza in Japan. There is limited evidence suggesting that, compared to other antiviral drugs, favipiravir might improve outcomes for people with COVID-19, but more rigorous studies are needed before any conclusions can be drawn.
Chinese clinical trials in Wuhan and Shenzhen claimed to show that favipiravir was "clearly effective". Of 35 patients in Shenzhen tested negative in a median of 4 days, while the length of illness was 11 days in the 45 patients who did not receive it. In a study conducted in Wuhan on 240 patients with pneumonia half were given favipiravir and half received umifenovir. The researchers found that patients recovered from coughs and fevers faster when treated with favipiravir, but that there was no change in how many patients in each group progressed to more advanced stages of illness that required treatment with a ventilator.
On 22 March 2020, Italy approved the drug for experimental use against COVID-19 and began conducting trials in the three regions most affected by the disease. The Italian Pharmaceutical Agency reminded the public that the existing evidence in support of the drug is scant and preliminary.
On 30 May 2020, the Russian Health Ministry approved a generic version of favipiravir named Avifavir, which proved highly effective in the first phase of clinical trials.
In June 2020, India approved the use of a generic version of favipravir called FabiFlu, developed by Glenmark Pharmaceuticals, in the treatment of mild to moderate cases of COVID-19.
On 26 May 2021, a systematic review found a 24% greater chance of clinical improvement when administered in the first seven days of hospitalization, but no statistically significant reduction in mortality for any of the groups, including hospitalized patients and those with mild or moderate symptoms.
Lopinavir/ritonavir
In March 2020, the main protease (3CLpro) of the SARS-CoV-2 virus was identified as a target for post-infection drugs. The enzyme is essential for processing the replication-related polyprotein. To find the enzyme, scientists used the genome published by Chinese researchers in January 2020 to isolate the main protease. Protease inhibitors approved for treating human immunodeficiency viruses (HIV) – lopinavir and ritonavir – have preliminary evidence of activity against the coronaviruses, SARS and MERS. As a potential combination therapy, they are used together in two Phase III arms of the 2020 global Solidarity project on COVID-19. A preliminary study in China of combined lopinavir and ritonavir found no effect in people hospitalized for COVID-19.
One study of lopinavir/ritonavir (Kaletra), a combination of the antivirals lopinavir and ritonavir, concluded that "no benefit was observed". The drugs were designed to inhibit HIV from replicating by binding to the protease. A team of researchers at the University of Colorado are trying to modify the drugs to find a compound that will bind with the protease of SARS-CoV-2. There are criticisms within the scientific community about directing resources to repurposing drugs specifically developed for HIV/AIDS because such drugs are unlikely to be effective against a virus lacking the specific HIV-1 protease they target. The WHO included lopinavir/ritonavir in the international Solidarity trial.
On 29 June, the chief investigators of the UK RECOVERY Trial reported that there was no clinical benefit from use of lopinavir-ritonavir in 1,596 people hospitalized with severe COVID-19 infection over 28 days of treatment.
A study published in October 2020, screening those drugs approved by the US Food and Drug Administration (FDA) which target SARS-CoV-2 spike (S) protein proposed that the current unbalanced combination formula of lopinavir might in fact interfere with the ritonavir's blocking activity on the receptor binding domain-human angiotensin converting enzyme-2 (RBD-hACE2) interaction, thus effectively limiting its therapeutic benefit in COVID-19 cases.
In 2022, the PANORAMIC trial is testing the effectiveness of nirmatrelvir combined with ritonavir, and molnupiravir in preventing hospitalization and helping faster recovery for people aged over 50 and those at higher risk due to underlying health conditions. As of March 2022 has over 16,000 people enrolled as participants making it the largest study into COVID-19 antivirals.
Remdesivir
Immunomodulatory treatments
Baricitinib
In May 2022, the US Food and Drug Administration (FDA) approved barictinib for the treatment of COVID-19 in hospitalized adults requiring supplemental oxygen, non-invasive or invasive mechanical ventilation, or extracorporeal membrane oxygenation (ECMO). Barictinib is the first immunomodulatory treatment for COVID-19 to receive FDA approval.
In the United States, barictinib is authorized under an emergency use authorization (EUA) for the treatment of COVID-19 in hospitalized people aged 2 to less than 18 years of age who require supplemental oxygen, non-invasive or invasive mechanical ventilation, or extracorporeal membrane oxygenation.
Immunosuppressants
Anakinra
In December 2021, anakinra (Kineret) was authorized in the European Union for the treatment of COVID-19 in adults with pneumonia requiring supplemental oxygen (low or high flow oxygen) and who are at risk of developing severe respiratory failure, as determined by blood levels of a protein called suPAR (soluble urokinase plasminogen activator receptor) of at least 6 ng per ml."
Interferons
Drugs with immune modulating effects that may prove useful in COVID-19 treatment include type I Interferons such as Interferon-β, peginterferon alpha-2a and -2b.
IFN-β 1b have been shown in an open label randomised controlled trial in combination with lopinavir/ ritonavir and ribavirin to significantly reduce viral load, alleviate symptoms and reduce cytokine responses when compared to lopinavir/ ritonavir alone.<Lancet 2020;395(10238):1695-1704> IFN-β will be included in the international Solidarity Trial in combination with the HIV drugs Lopinavir and Ritonavir. as well as the REMAP-CAP Finnish biotech firm Faron Pharmaceuticals continues to develop INF-beta for ARDS and is involved in worldwide initiatives against COVID-19, including the Solidarity trial. UK biotech firm Synairgen started conducting trials on IFN-β, a drug that was originally developed to treat COPD.
Steroids
Systemic corticosteroids have a small but statistically significant beneficial effect in reducing 30-day all-cause mortality in individuals hospitalized with COVID-19.
Budesonide
Administration of this inhaled steroid early in the course of COVID-19 infection has been found to reduce the likelihood of needing urgent medical care and reduced the time to recovery. More studies are on-going. In April 2021, budesonide was approved by authorities in the UK for off-label use to treat COVID-19 on a case-by-case basis.
Ciclesonide
Ciclesonide, an inhaled corticosteroid for asthma, was identified as a candidate antiviral in an in vitro drug screening assay done in South Korea. It has been used for treatment of pre-symptomatic COVID-19 patients and is undergoing clinical trials.
Dexamethasone
Dexamethasone is a corticosteroid medication in use for multiple conditions such as rheumatic problems, skin diseases, asthma and chronic obstructive lung disease among others. A multi-center, randomized controlled trial of dexamethasone in treating acute respiratory distress syndrome (ARDS), published in February 2020, showed reduced need for mechanical ventilation and mortality. Dexamethasone is only helpful in people requiring supplemental oxygen. Following an analysis of seven randomized trials, the WHO recommends the use of systemic corticosteroids in guidelines for treatment of people with severe or critical illness, and that they not be used in people that do not meet the criteria for severe illness.
On 16 June, the Oxford University RECOVERY Trial issued a press release announcing preliminary results that the drug could reduce deaths by about a third in participants on ventilators and by about a fifth in participants on oxygen; it did not benefit patients who did not require respiratory support. The researchers estimated that treating 8 patients on ventilators with dexamethasone saved one life, and treating 25 patients on oxygen saved one life. Several experts called for the full dataset to be published quickly to allow wider analysis of the results. A preprint was published on 22 June and the peer-reviewed article appeared on 17 July.
Based on those preliminary results, dexamethasone treatment has been recommended by the US National Institutes of Health (NIH) for patients with COVID-19 who are mechanically ventilated or who require supplemental oxygen but are not mechanically ventilated. The NIH recommends against using dexamethasone in patients with COVID-19 who do not require supplemental oxygen. In July 2020, the World Health Organization (WHO) stated they are in the process of updating treatment guidelines to include dexamethasone or other steroids.
The Infectious Diseases Society of America (IDSA) guideline panel suggests the use of glucocorticoids for patients with severe COVID-19; where severe is defined as patients with oxygen saturation (SpO2) ≤94% on room air, and those who require supplemental oxygen, mechanical ventilation, or extracorporeal membrane oxygenation (ECMO). The IDSA recommends against the use of glucocorticoids for those with COVID-19 without hypoxemia requiring supplemental oxygen.
In July 2020, the European Medicines Agency (EMA) started reviewing results from the RECOVERY study arm that involved the use of dexamethasone in the treatment of patients with COVID-19 admitted to the hospital to provide an opinion on the results. It focused particularly on the potential use of the drug for the treatment of adults with COVID-19.
In September 2020, the WHO released updated guidance on using corticosteroids for COVID-19. The WHO recommends systemic corticosteroids rather than no systemic corticosteroids for the treatment of people with severe and critical COVID-19 (strong recommendation, based on moderate certainty evidence). The WHO suggests not to use corticosteroids in the treatment of people with non-severe COVID-19 (conditional recommendation, based on low certainty evidence).
In September 2020, the European Medicines Agency (EMA) endorsed the use of dexamethasone in adults and adolescents (from twelve years of age and weighing at least ) who require supplemental oxygen therapy. Dexamethasone can be taken by mouth or given as an injection or infusion (drip) into a vein.
Hydrocortisone
In September 2020, a meta-analysis published by the WHO Rapid Evidence Appraisal for COVID-19 Therapies (REACT) Working Group found hydrocortisone to be effective in reducing mortality rate of critically ill COVID-19 patients when compared to other usual care or a placebo.
The use of corticosteroids can cause a severe and deadly "hyperinfection" syndrome for people with strongyloidiasis, which may be an underlying condition in populations exposed to the parasite Strongyloides stercoralis. This risk can be mitigated by the presumptive use of ivermectin before steroid treatment.
Methylprednisolone
In March–April 2020, a small bioinformatics company, AdvaitaBio, used its data analysis platform, iPathwayGuide, to analyze one of the first transcriptomics data sets that became available from COVID-19 patients. This analysis was able to identify methylprednisolone as a drug that could potentially help patients with severe cases of this disease. The analysis of the molecular data indicated that patients with severe COVID-19 suffered from the cytokine storm syndrome, and also identified the specific pathways and mechanisms through which methylprednisolone would help revert many of the important gene expression changes induced by the cytokine storm. A subsequent clinical trial undertaken in the Henry Ford Health Systems showed that methylprednisolone reduced mortality by approximately 44% (from 29.6% to 16.6%). The results contradicted flagrantly the recommendations of the World Health Organization, which at the time, had a standing recommendation NOT to use systemic steroids in COVID-19 patients. This, together with the very tense scientific environment cause by theretraction of some early COVID-19-related papers, delayed the publication of these results by several months. This was very unfortunate, since methylprednisolone is low-cost and widely available and could have prevented many thousands of deaths. Several months later, the results of the RECOVERY trial (see dexamethasone above) also showed steroids as being effective in reducing mortality, and helped change the general opinion about steroid treatments in COVID-19. The drug repurposing analysis that was first to propose a steroid for severe COVID-19 case was eventually published in the journal Bioinformatics Currently, steroids including methylprednisolone and dexamethasone are part of the standard of care in severe cases of COVID-19.
For a composite end point of preventing ICU admission, need for mechanical ventilator or mortality, the number needed to treat (NNT) to benefit a single patient was only 5 for methylprednisolone when used early in hospitalization. The NNT necessary for methylprednisolone to avoid a death was only 8 for all hospitalized patients. This is in contrast to the RECOVERY trial (NCT04323592) for dexamethasone (see Dexamethasone above), where NNT was 8 for patients on mechanical ventilation, and 25 for patients needed oxygen to prevent mortality.
Vitamins
Vitamin C
Supplementation with vitamin C, has been suggested as part of the supportive management of COVID-19, as serum levels of the vitamin are depleted in the acute stage of infection owing to increased metabolic demands. In April 2021, the US National Institutes of Health (NIH) COVID-19 Treatment Guidelines stated that "there are insufficient data to recommend either for or against the use of vitaminC for the prevention or treatment of COVID-19." In an update posted December 2022, the NIH position was unchanged:
There is insufficient evidence for the COVID-19 Treatment Guidelines Panel (the Panel) to recommend either for or against the use of vitamin C for the treatment of COVID-19 in nonhospitalized patients.
There is insufficient evidence for the Panel to recommend either for or against the use of vitamin C for the treatment of COVID-19 in hospitalized patients.
Three meta-analyses of people hospitalized with severe COVID-19 - with a high overlap in the clinical trials being included - reported a significant reduction in the risk of all-cause, in-hospital mortality with the administration of vitamin C relative to no vitamin C. There were no significant differences in ventilation incidence, hospitalization duration or length of intensive care unit stay between the two groups. The majority of the trials used intravenous administration of the vitamin. Acute kidney injury was lower in people treated with vitamin C treatment. There were no differences in the frequency of other adverse events due to the vitamin. All three journal articles concluded that further large-scale studies are needed to affirm its mortality benefits before issuing updated guidelines and recommendations.
Vitamin D
During the COVID-19 pandemic, there has been interest in vitaminD status and supplements, given the significant overlap in the risk factors for severe COVID-19 and vitaminD deficiency. These include obesity, older age, and Black or Asian ethnic origin, and it is notable that vitaminD deficiency is particularly common within these groups.
The National Institutes of Health (NIH) COVID-19 Treatment Guidelines states "there is insufficient evidence to recommend either for or against the use of vitamin D for the prevention or treatment of COVID-19."
The general recommendation to consider taking vitamin D supplements, particularly given the levels of vitamin D deficiency in Western populations, has been repeated. , the English National Institute for Health and Care Excellence (NICE) continued to recommend small doses of supplementary vitaminD for people with little exposure to sunshine, but recommended that practitioners should not offer a vitaminD supplement solely to prevent or treat COVID-19, except as part of a clinical trial.
Multiple studies have reported links between pre-existing vitamin D deficiency and the severity of the disease. Several systematic reviews and meta-analyses of these show that vitamin D deficiency may be associated with a higher probability of becoming infected with COVID-19, and have clearly demonstrated there are significant associations between deficiency and a greater severity of the disease, including relative increases in hospitalization and mortality rates of about 80%. The quality of some of the studies included and whether this demonstrates a causal relationship has been questioned.
Many clinical trials are underway or have been completed assessing the use of oral vitaminD and its metabolites such as calcifediol for prevention or treatment of COVID-19 infection, especially in people with vitamin D deficiency.
The effects of oral vitamin D supplementation on the need for intensive care unit (ICU) admission and mortality in hospitalized COVID-19 patients has been the subject of a meta-analysis. A much lower ICU admission rate was found in patients who received vitamin D supplementation, which was only 36% of that seen in patients without supplementation (p<0.0001). No significant effects on mortality were found in this meta-analysis. The certainty of these analyses is limited by the heterogenicity in the studies which include both vitamin D3 (cholecalciferol) and calcifediol, but these findings indicate a potential role in improving COVID-19 severity, with more robust data being required to substantiate any effects on mortality.
Calcifediol, which is 25-hydroxyvitamin D, is more quickly activated, and has been used in several trials. Review of the published results suggests that calcifediol supplementation may have a protective effect on the risk of ICU admissions in COVID-19 patients.
Minerals
Zinc
The National Institutes of Health (NIH) COVID-19 Treatment Guidelines states "there is insufficient evidence to recommend either for or against the use of zinc for the treatment of COVID-19" and that "the Panel recommends against using zinc supplementation above the recommended dietary allowance for the prevention of COVID-19, except in a clinical trial (BIII)."
Others
Antibiotics: Some antibiotics that have been identified as potentially repurposable as COVID-19 treatments, including:
Broad-spectrum antibiotics: In 2021, the importance of drug repurposing for COVID-19 led to the establishment of broad-spectrum antibiotics. Broad-spectrum therapeutics are effective against multiple types of pathogens. Such drugs have been suggested as potential emergency treatments for future pandemics.
Teicoplanin,
Oritavancin,
Dalbavancin,
Monensin,
Azithromycin.
Bucillamine: On 31 July 2020, the U.S. Food and Drug Administration (FDA) authorized Revive Therapeutics to proceed with a randomized, double-blind, placebo-controlled confirmatory Phase III clinical trial protocol to evaluate the safety and efficacy of the antirheumatic agent bucillamine in patients with mild-moderate COVID-19.
Clofoctol, a bacteriostatic antibiotic, has been proposed as a treatment for COVID-19. A study in mice showed that clofoctol blocks the replication of SARS-CoV-2.
Colchicine: Researchers from the Montreal Heart Institute in Canada are studying the role of colchicine in reducing inflammation and pulmonary complications in patients with mild symptoms of COVID-19. The study, named COLCORONA, was recruiting 6000 adults 40 and older who were diagnosed with COVID-19 and experienced mild symptoms not requiring hospitalization. Women who were pregnant or breastfeeding or who did not have an effective contraceptive method were not eligible. The trial results are favorable, but inconclusive.
Fenofibrate and bezafibrate have been suggested for treatment of life-threatening symptoms of COVID-19. Fenofibrate also lowered severe progressive inflammation markers in hospitalized COVID-19 patients within 48 hours of treatment in an Israeli study. It showed extremely promising results by interfering with how coronavirus reproduce.
nanoFenretinide is nanoparticle sized fenretinide and repurposed oncology drug approved to enter the clinic for a lymphoma indication. It was identified as a candidate antiviral in an in vitro drug screening assay done in South Korea. Fenretinide's clinical safety profile also makes it an ideal candidate in combination regimens.
Histamine H2 receptor antagonists are under investigation.
Cimetidine has been suggested as a treatment for COVID-19.
Famotidine has been suggested as a treatment for COVID-19, and a clinical study is underway.
Ibuprofen: A trial called "Liberate" has been started in the United Kingdom to determine the effectiveness of ibuprofen in reducing the severity and progression of lung injury which results in breathing difficulties for COVID-19 patients. Subjects are to receive three doses of a special formulation of the druglipid ibuprofenin addition to usual care.
Influenza vaccine: A clinical cohort study in Brazil found that COVID-19 patients who received a recent influenza vaccine needed less intensive care support, less invasive respiratory support, and were less likely to die.
Sildenafil, more commonly known by the brand name Viagra, is proposed as a treatment for COVID-19, and a PhaseIII clinical trial is underway.
Found ineffective
The use of aspirin, hydroxychloroquine, azithromycin, and colchicine were found ineffective against COVID-19. The use of the combination of lopinavir and ritonavir together was found ineffective against COVID-19. The use of the combination of etesevimab and bamlanivimab together was found ineffective against the Omicron variant.
References
Further reading
External links
Virus research
COVID-19 drug development
Articles containing video clips | COVID-19 drug repurposing research | [
"Chemistry",
"Biology"
] | 6,904 | [
"Viruses",
"COVID-19 drug development",
"Drug discovery",
"Virus research"
] |
63,431,417 | https://en.wikipedia.org/wiki/David%20W.%20Green%20%28biochemist%29 | David W. Green ( - 1976) was a crystallographer at the Medical Research Council Unit for the Study of the Molecular Structure of Biological Systems, Cavendish Laboratory, University of Cambridge.
David W. Green was a graduate student in the laboratory of Max Perutz at the University of Cambridge from 1952 to 1955 and obtained a Ph.D. He is known for demonstrating the first use of isomorphous replacement to solve the phase problem in X-ray crystallography.
After completing his Ph.D., Green moved to the Davy-Faraday Research Laboratory at The Royal Institution in autumn 1955.
He was recruited by Linus Pauling but ultimately moved to MIT to work with Alexander Rich. With Rich, Green solved the structure of N-methyluracil. After his postdoctoral work, he returned to the Davy-Faraday Research Laboratory at The Royal Institution in London, England to continue his crystallographic research. Later he moved to the Department of Physics at the University of Edinburgh. In Edinburgh, Green was a senior lecturer and ran a group in solid state physics.
Green died in 1976.
References
1976 deaths
British crystallographers
English biochemists | David W. Green (biochemist) | [
"Chemistry"
] | 238 | [
"Biochemistry stubs",
"Biochemists",
"Biochemist stubs"
] |
63,431,581 | https://en.wikipedia.org/wiki/Selfing%20syndrome | Selfing syndrome refers to plants that are autogamous and display a complex of characteristics associated with self-pollination. The term was first coined by Adrien Sicard and Michael Lenhard in 2011, but was first described in detail by Charles Darwin in his book “The Effects of Cross and Self Fertilisation in the Vegetable Kingdom” (1876), making note that the flowers of self-fertilizing plants are typically smaller and have little distance between reproductive organs.
Characteristics
Plants that exhibit selfing syndrome typically possess reduced pigmentation and flower size, reduced herkogamy, and the lack of reward for pollinators. Differences between outcrossing species versus selfing species can be clearly distinguished in plants such as Collinsia grandiflora, an outcrossing species, and the selfing species Collinsia parviflora.
Life form of selfing species
Plants exhibiting selfing syndrome are typically autogamous and display reduced pollen ovule (P/O) ratios, resulting in a smaller pollen count and a larger number of ovules. The reduction of flower size has been studied between the selfing species Capsella rubella and its closely related outcrossing relative Capsella grandiflora. The petals between the two species grow at the same rate, however, a decrease in the sterile apetela (SAP) protein activity due to variation in the SAP intron in C. rubella is responsible for reduced petal size. This is due to the smaller number of cells present in the petal and results in petals that are around 35% smaller than the petals of C. grandiflora. Along with reduced flower size, plants exhibiting selfing syndrome typically have reduced numbers of open flowers compared to those that outcross. Selfing plants have also been found to have a larger geographic range, close to two times larger range than plants that outcross and can also be found around 110 kilometers higher in latitude.
References
Plant reproduction | Selfing syndrome | [
"Biology"
] | 399 | [
"Behavior",
"Plant reproduction",
"Plants",
"Reproduction"
] |
63,432,250 | https://en.wikipedia.org/wiki/NGC%20901 | NGC 901 is an elliptical galaxy in the constellation Aries. It is estimated to be 441 million light years from the Milky Way and has a diameter of approximately 50,000 ly. NGC 901 was discovered on September 5, 1864, by Albert Marth.
See also
List of NGC objects (1–1000)
References
External links
Aries (constellation)
0901
Elliptical galaxies
212967 | NGC 901 | [
"Astronomy"
] | 83 | [
"Aries (constellation)",
"Constellations"
] |
63,432,445 | https://en.wikipedia.org/wiki/NGC%20902 | NGC 902 is a barred spiral galaxy in the constellation Cetus. It is estimated to be 314 million light-years from the Milky Way and has a diameter of approximately 50,000 ly. NGC 902 was discovered on November 28, 1885 by Francis Leavenworth.
See also
List of NGC objects (1–1000)
References
External links
Barred spiral galaxies
0902
Cetus
009021 | NGC 902 | [
"Astronomy"
] | 83 | [
"Cetus",
"Constellations"
] |
63,432,468 | https://en.wikipedia.org/wiki/NGC%20903 | NGC 903 is a lenticular galaxy in the constellation Aries. It is estimated to be about 230 million light-years from the Milky Way and has a diameter of approximately 35,000 ly. NGC 903 was discovered on 13 December 1884 by the astronomer Edouard Stephan.
See also
List of NGC objects (1–1000)
References
External links
Lenticular galaxies
0903
Aries (constellation)
009097
Astronomical objects discovered in 1884
Discoveries by Édouard Stephan | NGC 903 | [
"Astronomy"
] | 96 | [
"Aries (constellation)",
"Constellations"
] |
63,432,496 | https://en.wikipedia.org/wiki/NGC%20910 | NGC 910 is an elliptical galaxy in the constellation of Andromeda. NGC 910 was discovered on October 17, 1786 by the German-British astronomer William Herschel. It is the brightest galaxy in the cluster Abell 347.
See also
List of NGC objects (1–1000)
References
External links
Elliptical galaxies
0910
Andromeda (constellation)
009201 | NGC 910 | [
"Astronomy"
] | 76 | [
"Andromeda (constellation)",
"Constellations"
] |
63,432,596 | https://en.wikipedia.org/wiki/Chloroacetophenone%20oxime | Chloroacetophenone oxime is the oxime derivative of chloroacetophenone. It is produced by reaction of chloroacetophenone with hydroxylamine. It has powerful lachrymatory and irritant effects.
References
Lachrymatory agents
Ketoximes
Phenyl compounds
Organochlorides | Chloroacetophenone oxime | [
"Chemistry"
] | 75 | [
"Chemical weapons",
"Organic compounds",
"Lachrymatory agents",
"Organic compound stubs",
"Organic chemistry stubs"
] |
63,433,026 | https://en.wikipedia.org/wiki/ASTELCO | The company ASTELCO Systems is a manufacturer of telescopes, telescope control systems, domes/enclosures and related technology for professional astronomical research or public use. ASTELCO is located in Martinsried near Munich and was founded in 2004.
The company built the telescope and mount of the TRAPPIST Telescopes, famous for the discovery of the TRAPPIST-1 system, a red dwarf with seven terrestrial planets. The company also built the telescopes and mounts for the SPECULOOS Southern and Northern Observatory, which are searching for terrestrial planets around ultracool dwarfs and brown dwarfs in the habitable zone. Other projects include the 60 cm Robotic Telescope BOOTES-5 in Mexico, the COATLI robotic 50 cm telescope in Sierra San Pedro Mártir and the prototype for ESO VLT Laser Guide Star Telescope.
The company builds classical Cassegrain and Ritchey-Chrétien telescope designs. The company also builds entire observatories, like the 0.8 m robotic telescope and 8m Lotus dome on top of the Mary Library (Turkmenistan) that is available for public use.
References
Instrument-making corporations
Telescope manufacturers
Manufacturing companies based in Munich | ASTELCO | [
"Astronomy"
] | 232 | [
"Telescope manufacturers",
"People associated with astronomy"
] |
63,434,051 | https://en.wikipedia.org/wiki/ISO/IEC%2027017 | ISO/IEC 27017 is a security standard developed for cloud service providers and users to make a safer cloud-based environment and reduce the risk of security problems. It was published by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC) under the joint ISO and IEC subcommittee, ISO/IEC JTC 1/SC 27. It is part of the ISO/IEC 27000 family of standards, standards which provides best practice recommendations on information security management. This standard was built from ISO/IEC 27002, suggesting additional security controls for the cloud which were not completely defined in ISO/IEC 27002.
This International Standard provides guidelines supporting the implementation of information security controls for cloud service customers, who implements the controls, and cloud service providers to support the implementations of those controls. The selection of appropriate information security controls and the application of the implementation guidance provided, will depend on a risk assessment and any legal, contractual, regulatory or other cloud-sector specific information security requirements.
What does the standard provide?
ISO/IEC 27017 provides guidelines for information security controls applicable to the use of cloud services by providing an additional implementation guidance for 37 controls specified in ISO/IEC 27002 and 7 additional controls related to cloud services which address the following:
Who is responsible for what between the cloud service provider and the cloud customer.
The removal or return of assets at the end of a contract.
Protection and separation of the customer's virtual environment.
Virtual machine configuration.
Administrative operations and procedures associated with the cloud environment.
Cloud customer monitoring of activity.
Virtual and cloud network environment alignment.
Structure of the standard
The official title of the standard is "Information technology — Security techniques — Code of practice for information security controls based on ISO/IEC 27002 for cloud services".
ISO/IEC 27017:2015 has eighteen sections, plus a long annex, which cover:
1. Scope
2. Normative References
3. Definitions and abbreviations
4. Cloud sector-specific concepts
5. Information security policies
6. Organization of information security
7. Human resource security
8. Asset management
9. Access control
10. Cryptography
11. Physical and environmental security
12. Operations security
13. Communications security
14. System acquisition, development and maintenance
15. Supplier relationships
16. Information security incident management
17. Information security aspects of business continuity management
18. Compliance
References
External links
ISO Website
Computer security standards
Information assurance standards
27017 | ISO/IEC 27017 | [
"Technology",
"Engineering"
] | 487 | [
"Computer security standards",
"Computer standards",
"Information assurance standards",
"Cybersecurity engineering"
] |
63,434,380 | https://en.wikipedia.org/wiki/Cultrex%20BME | Cultrex Basement Membrane Extract (BME) is the trade name for a extracellular protein mixture secreted by Engelbreth-Holm-Swarm (EHS) mouse sarcoma cells and manufactured into a hydrogel by R&D Systems, a brand of Bio-Techne. Similar to Matrigel, this hydrogel is a natural extracellular matrix that mimics the complex extracellular environment within complex tissues. It is used as a general cell culture substrate across a wide variety of research applications.
Composition
The major components of Cultrex BME include laminin, collagen, entactin/nidogen, and heparin sulfate proteoglycans. These components are found in the basement membrane extracellular matrix that forms an interface between stromal tissue and adjacent endothelial, epithelial, muscle, or neuronal cells. Also present in Cultrex BME are growth factors, however these can be reduced during production of the hydrogel. Reduced growth factor (RGF) Cultrex BME is commonly used for the culture of pluripotent stem cells and organoids.
Cell culture
Cultrex BME is gelatinous at 4 °C. The matrix proteins polymerize and solidify at temperatures above 18 °C. Ice-cold basement membrane extract can be dispensed directly onto plastic cell culture labware or it can be diluted in ice-cold phosphate buffered saline or cell culture media prior to dispensing.
Due to its heterogenous extracellular matrix protein composition, cells cultured using basement membrane extract show complex cellular behaviors that are difficult to reproduce under laboratory conditions. These include cell adhesion, migration, invasion, proliferation, differentiation, and endothelial cell tube formation. EHS tumor-derived matrices, such as Cultrex BME, are used for a variety of cell culture applications, including angiogenesis, spheroid formation, organoid culture, pluripotent stem cell culture, xenograft, and in vivo and in vitro tumor modeling
Pluripotent stem cells
Cultrex BME is used as an attachment substrate to promote the expansion and maintenance of induced pluripotent stem cells and embryonic stem cells in the absence of feeder cells. The extracellular matrix proteins that compose the basement membrane extract are needed to maintain stem cells in an undifferentiated state during prolonged cell culture. For expanding stem cells, the hydrogel is commonly diluted prior to coating cell culture plasticware. Concentrated Cultrex BME is often used during cell differentiation or transitioning pluripotent stem cells into organoid or spheroid culture.
Organoid and 3D cell culture
Proliferation and differentiation of spheroids and organoids, derived from induced pluripotent stem cells or adult tissue-specific stem cells, is supported by EHS-derived hydrogels such as Cultrex BME. EHS-derived hydrogels have been used to generate a variety of organoids, including intestinal, lung, liver, and snake venom gland
[SS1]
References
External links
Cultrex BME
Proteins | Cultrex BME | [
"Chemistry"
] | 642 | [
"Biomolecules by chemical classification",
"Proteins",
"Molecular biology"
] |
63,434,654 | https://en.wikipedia.org/wiki/NGC%20940 | NGC 940 is a lenticular galaxy in the constellation Triangulum. It is estimated to be 222 million light-years from the Milky Way and has a diameter of approximately 80,000 ly. NGC 940 was discovered by Heinrich d'Arrest.
One supernova, SN 2021vtl (type Ia, mag. 17.3), was discovered in NGC 940 on 11 August, 2021.
See also
List of NGC objects (1–1000)
References
External links
0940
Triangulum
Lenticular galaxies
009478 | NGC 940 | [
"Astronomy"
] | 112 | [
"Triangulum",
"Constellations"
] |
63,434,692 | https://en.wikipedia.org/wiki/NGC%20980 | NGC 980 is a lenticular galaxy located in the constellation Andromeda about 256 million light years from the Milky Way. It was discovered by the German - British astronomer William Herschel in 1786.
iPTF 13ebh, a type Ia supernova, occurred in NGC 980.
References
Lenticular galaxies
0980
Andromeda (constellation)
009831 | NGC 980 | [
"Astronomy"
] | 74 | [
"Andromeda (constellation)",
"Constellations"
] |
63,434,895 | https://en.wikipedia.org/wiki/AK%20Scorpii | AK Scorpii is a Herbig Ae/Be star and spectroscopic binary star about 459 light-years distant in the constellation Scorpius. The star belongs to the nearby Upper Centaurus–Lupus star-forming region and the star is actively accreting material. The binary is surrounded by a circumbinary disk that was imaged with VLT/SPHERE in scattered light and with ALMA.
Characteristics
AK Scorpii is about 18 million years old, which is young on astronomical timescales. The binary consists out of two stars with an equal mass of 1.25 respectively and the two stars orbit each other within 13.6 days. The binary is surrounded by a narrow ring of dust with a radius of about 30 astronomical units and the gap between the binary and the dust disk is filled by some gas.
The binary is in an eccentric orbit that causes variable accretion rates due to gravitational interactions with the disk. During the furthest point in the orbit of the binary (apastron), matter is dragged from the inner disk border into the gap. The material forms accretion streams that fill ring-like structures around each component of the binary. At the closest point in the orbit (periastron), the ring-like structures come into contact, leading to an angular momentum loss and thus producing an accretion outburst.
In August 2014 the system was observed with the Hubble Space Telescope during the periastron passage. The telescope observed a drop of the hydrogen flux, which is explained by the occultation of the star by a gas stream falling towards the star. The system also shows an enhanced X-ray and ultraviolet flux with XMM-Newton data during periastron, which is an additional sign of stronger accretion during periastron.
The orbital inclination of the binary and the inclination of the circumbinary disk is nearly the same. Any circumbinary planet that could form in this disk would orbit in the same plane as the binary.
The spectrum of the stars shows that their atmosphere is overabundant in the chemical elements yttrium, barium, and lanthanum. The primary additionally shows an overabundance of zirconium and the secondary is overabundant in sulphur.
References
Circumstellar disks
Herbig Ae/Be stars
Binary stars
Scorpius
Upper Centaurus Lupus
082747
Scorpii, AK
152404
Durchmusterung objects | AK Scorpii | [
"Astronomy"
] | 514 | [
"Scorpius",
"Constellations"
] |
63,435,456 | https://en.wikipedia.org/wiki/Zoom%20%28software%29 | Zoom Workplace (commonly known and stylized as zoom) is a proprietary videotelephony software program developed by Zoom Communications. The free plan allows up to 100 concurrent participants, with a 40-minute time restriction. Users have the option to upgrade by subscribing to a paid plan, the highest of which supports up to 1,000 concurrent participants for meetings lasting up to 30 hours.
History
A beta version of Zoom that could host conferences with only up to 15 video participants was launched on August 21, 2012. On January 25, 2013, version 1.0 of the program was released with an increase in the number of participants per conference to 25. By the end of its first month, Zoom had 400,000 users. By 2013, Zoom had more than one million users. After the start of the COVID-19 pandemic, by February 2020, Zoom had gained 2.22 million users in 2020 – more users than it amassed in the entirety of 2019. In March 2020, the Zoom app was downloaded 2.13 million times.
During the COVID-19 pandemic, there was a major increase in the use of Zoom for remote work, distance education, and online social relations. Zoom was one of the most downloaded mobile apps worldwide in 2020 with over 500 million downloads.
As of April 2020, Zoom had more than 300 million daily meeting participants (calculated as the number of times someone joins a meeting, which can happen multiple times per day).
Features
Zoom One has six tiers: Basic, Pro, Business, Business Plus, Enterprise, and Enterprise Plus. Zoom is compatible with Windows, macOS, iOS, Android, ChromeOS, and Linux. It is noted for its simple interface and usability, regardless of technological expertise. Features include one-on-one meetings, group video conferences, screen sharing, plugins, browser extensions, and the ability to record meetings and have them automatically transcribed. On some computers and operating systems, users are able to select a virtual background, which can be downloaded from different sites, to use as a backdrop behind themselves.
Use of the platform is free for video conferences of up to 100 participants at once, with a 40-minute time limit. There is a 10-minute timeout period between free 40-minute meetings. For longer or larger conferences with more features, paid subscriptions are available. Features geared towards business conferences, such as Zoom Rooms, are also available. Up to 49 people can be seen on a desktop or laptop screen at once, up to 4 people per screen in iPhone and Android mobile phones and tablet computers, and up to 16 people per screen on iPad.
Zoom security features include password-protected meetings, user authentication, waiting rooms, locked meetings, disabling participant screen sharing, randomly generated IDs, and the ability for the host to remove disruptive attendees. As of June 2020, Zoom began offering end-to-end encryption to business and enterprise users, with AES 256 GCM encryption enabled for all users. In October 2020, Zoom added end-to-end encryption for free and paid users. It is available on all platforms, except for the official Zoom web client.
Zoom also offers a transcription service using Otter.ai software that allows businesses to store transcriptions of the Zoom meetings online and search them, including separating and labeling different speakers.
In July 2020, Zoom Rooms and Zoom Phone became available as hardware as a service products. As of July 2022, Zoom Phone is available for domestic telephone service in 47 countries, and the company has sold 3 million seats for the service. Zoom for Home, a category of products designed for home use, became available in August 2020. Zoom Phone Provider Exchange, which gives customers options for voice services, reaches more than 70 countries. In July 2022, an option was added on Zoom Phone to turn on end-to-end encryption during one-on-one calls between users on the same company account.
In September 2020, Zoom added new accessibility features to make the app easier to use for those who are deaf, hard of hearing, or visually impaired. New features include the ability to move around video windows in gallery view, pin video windows to be spotlighted; improved keyboard shortcuts; new tools to adjust the size of closed captioning text; and sign language interpreters' windows can now sit directly next to the speaker.
In October 2020 at Zoomtopia, Zoom's annual user conference, the company unveiled OnZoom, a virtual event marketplace with an integrated payment system where users can host and promote free or paid live events. With OnZoom, users will be able to schedule and host one-time events or event series for up to 1,000 attendees and sell tickets online. The company also announced Zoom Apps, a feature integrating third-party apps so they can be used within the Zoom interface during meetings. The first such apps were expected to be available around the end of 2020, from companies including Slack, Salesforce, Dropbox, and Qatalog. In October 2020, Zoom gave its users better security with an upgrade to end-to-end encryption for its online meetings network.
Also in October 2020, Zoom signed a carrier agreement with Global BT Business to offer a fully managed Zoom Meetings service featuring a choice of connectivity and integration with its global voice network.
In February 2021, Zoom added a "virtual receptionist" feature in the Kiosk Mode for Zoom Rooms. The feature was created to cater to in-person visitors at a business to interact in the lobby without physical contact.
On March 22, 2021, Zoom announced that it would start selling its videoconferencing technology as a white-label product, so other companies can embed it in their own products, with the calls running over Zoom but not carrying the company's brand name.
In July 2021, Zoom released Zoom Apps which integrated a marketplace of third-party applications such as Dropbox Spaces, Asana, and SurveyMonkey.
In August 2021, Zoom launched Focus Mode, designed for use in educational settings. When active, the mode will hide participants' screens from each other (though they can see each other's names) while the host retains the ability to see everyone's camera stream or screen share. The feature is available across all Zoom accounts, including free ones.
In September 2021 at Zoomtopia, the company announced that end-to-end encryption would now be available as an upgrade for Zoom Phone users. The company also announced bring your own key (BYOK) (for users to manage their own encryption keys that Zoom cannot access or see), Verified Identity (a multi-factor authentication feature working through Okta that allows users to confirm the identity of meeting participants), and Video Engagement Center (for businesses to digitally interact with customers). Other updates include revamped virtual whiteboard features, including touchscreen whiteboards that can be digitized for remote participants, and improved collaboration between Zoom Meetings and Zoom Chat.
In October 2021, the option to automatically generate closed captions in English for Zoom meetings was expanded to all accounts, including free ones. The feature had previously only been available for Premium users.
In April 2022, Zoom added features including gesture recognition, a virtual whiteboard, and Zoom IQ for sales. In February 2022, the company launched Zoom Contact Center, a cloud contact center optimized for video calls and integrated directly into Zoom.
In June 2022, Zoom One, which brings together chat, phone, whiteboard, and video conferencing capabilities into a single offering, was launched. Also in June 2022, Zoom opened its Zoom Apps developer program to all developers, via Zoom Apps SDK. With the release of Zoom One, the company offers video conferencing translation and captioning for 11 languages: English, simplified Chinese, Dutch, French, German, Italian, Japanese, Korean, Russian, Spanish, and Ukrainian. This feature is available with the Business Plus and Enterprise Plus plans.
A version for Apple TV was released on December 1, 2023, which requires using an external iOS device as the user's camera.
Usage
Zoom is used by a variety of individuals and private and public organizations, including banks, schools, universities, healthcare providers, and government agencies, and for ceremonies such as birthday parties, funeral services, and bar and bat mitzvah services. In 2020, Zoom formed a partnership with Formula One to create a virtual club where fans can go behind the scenes and take part in virtual activities through Zoom, beginning with the Hungarian Grand Prix. An article published in July 2020 in the San Francisco Chronicle noted a new real estate trend in San Francisco and Oakland where some listings include "Zoom rooms" with backdrops for Zoom calls.
Richard Nelson's play What Do We Need to Talk About? takes place on Zoom, with its main characters congregating online during the COVID-19 pandemic using the platform. Written and directed by Nelson, it was commissioned by The Public Theater and premiered on YouTube on April 29, 2020, as a benefit performance. The New Yorker called it "the first great original play of quarantine". Oprah's Your Life in Focus: A Vision Forward was a live virtual experience hosted by Oprah Winfrey on Zoom from May 16 through June 6, 2020. In Source Material's 2020 play, In These Uncertain Times, directed by Samantha Shay, characters communicate on Zoom. The British found-footage horror film Host, directed by Rob Savage, features a group of young people attempting to contact spirits through a remote séance on Zoom, and premiered on Shudder in July 2020. A live reading of Kristoffer Diaz's 2009 play The Elaborate Entrance of Chad Deity over Zoom streamed on Play-PerView from August 15t to August 20, 2020. In the 2021 film Locked Down, directed by Doug Liman and starring Anne Hathaway and Chiwetel Ejiofor, characters communicate through Zoom conferences.
From July 3 to 4, 2020, the International Association of Constitutional Law and Alma Mater Europaea used Zoom Webinar to conduct the first "round-the-clock and round-the-globe" event, featuring 52 speakers from 28 countries and several time zones. Soon after, a format of conferences that "virtually travel the globe with the sun from East to West", became common, some of them running for several days.
On September 17, 2020, a live table read of the script for the 1982 film Fast Times at Ridgemont High was hosted by Dane Cook, with performers including Brad Pitt, Jennifer Aniston, Julia Roberts, original cast member Sean Penn, Matthew McConaughey, Shia LaBeouf, Morgan Freeman (who served as the narrator), Jimmy Kimmel, Ray Liotta, and John Legend, to raise money for the charity CORE. The broadcast of the 72nd Primetime Emmy Awards on September 20, 2020, hosted by Jimmy Kimmel, featured nominees participating through Zoom. On an alternate music video for the 2020 single "Ice Cream" by Blackpink featuring Selena Gomez, the artists appeared via Zoom from their homes. The series Zoom Where It Happens, airing on Zoom as a partnership between Zoom and Black female artists, launched in September 2020 with a virtual table read of an episode of The Golden Girls, reimagined with an all-Black cast. The second episode featured an all-Black cast in a table read of an episode of Friends, hosted by Gabrielle Union and featuring Sterling K. Brown and Uzo Aduba.
Familiarity with Zoom meetings in nation-state diplomatic and bureaucratic circles, partially due to the global COVID-19 pandemic, substantially contributed to the efficacy of the Western response to the 2022 Russian invasion of Ukraine
Reception
Zoom has been criticized for "security lapses and poor design choices" that have resulted in heightened scrutiny of its software. Many of Zoom's issues "surround deliberate features designed to reduce friction in meetings", which Citizen Lab found to "also, by design, reduce privacy or security". In March 2020, New York State Attorney General Letitia James launched an inquiry into Zoom's privacy and security practices. The inquiry was closed on May 7, 2020, with Zoom not admitting wrongdoing, but agreeing to take added security measures. In April 2020, CEO Yuan apologized for the security issues, stating that some of the issues were a result of Zoom's having been designed for "large institutions with full IT support". He noted that in December 2019, Zoom had a maximum of 10 million daily meeting participants, and in March 2020 the software had more than 200 million daily meeting participants, bringing the company increased challenges. Zoom agreed to focus on data privacy and issue a transparency report. In April 2020, the company released Zoom version 5.0, which addressed a number of the security and privacy concerns. It includes passwords by default, improved encryption, and a new security icon for meetings. In September 2020, Zoom added support for two-factor authentication to its desktop and mobile apps; the security feature was previously Web-only.
As of April 2020, businesses, schools, and government entities who have restricted or prohibited the use of Zoom on their networks include Google, Siemens, the Australian Defence Force, the German Ministry of Foreign Affairs, the Indian Ministry of Home Affairs, SpaceX, and the New York City Department of Education. In May 2020, the New York City Department of Education lifted their ban on Zoom after the company addressed security and privacy concerns.
Privacy
Zoom has been criticized for its privacy and corporate data sharing policies, as well as for enabling video hosts to potentially violate the privacy of those participating in their calls.
In March 2020, a Motherboard article found that the company's iOS app was sending device analytics data to Facebook on startup, regardless of whether a Facebook account was being used with the service, and without disclosing it to the user. Zoom responded that it had been made aware of the issue and patched the app to remove the SDK after learning that it was collecting unnecessary device data. The company stated that the SDK was only collecting information on the user's device specifications (such as model names and operating system versions) in order to optimize its service and that it was not collecting personal information. In the same month, Zoom was sued by a user in U.S. Federal Court for illegally and secretly disclosing personal data to third parties, including Facebook. Zoom responded that it "has never sold user data in the past and has no intention of selling users' data going forward".
In April 2020, a Zoom information gathering feature was found that automatically sent user names and email addresses to LinkedIn, allowing some participants to surreptitiously access LinkedIn profile data about other users without their express consent. Soon after, the companies disabled their integration. In May 2020, the Federal Trade Commission announced that it was looking into Zoom's privacy practices. The FTC alleged in a complaint that since at least 2016, "Zoom maintained the cryptographic keys that could allow Zoom to access the content of its customers' meetings, did not provide advertised end-to-end encryption, falsely claimed HIPAA compliance, installed the ZoomOpener webserver without adequate consent, did not uninstall the web server after uninstalling the Zoom App, and secured its Zoom Meetings with a lower level of encryption than promised." On November 9, 2020, a settlement was reached, requiring the company to stop misrepresenting security features, create an information security program, obtain biannual assessments by a third party, and implement additional security measures.
Security
Vulnerabilities
In November 2018, a security vulnerability was discovered that allowed a remote unauthenticated attacker to spoof UDP messages that allowed the attacker to remove attendees from meetings, spoof messages from users, or hijack shared screens. The company released fixes shortly after the vulnerability was discovered. In July 2019, security researcher Jonathan Leitschuh disclosed a zero-day vulnerability allowing any website to force a macOS user to join a Zoom call, with their video camera activated, without the user's permission. Attempts to uninstall the Zoom client on macOS would prompt the software to re-install automatically in the background using a hidden web server that was set up on the machine during the first installation so that it remains active even after attempting to remove the client. After receiving public criticism, Zoom removed the vulnerability and the hidden webserver to allow complete uninstallation. In April 2020, security researchers found vulnerabilities where Windows users' credentials could be exposed. Another vulnerability allowing unprompted access to cameras and microphones was made public. Zoom issued a fix in April 2020.
Motherboard reported that there were two Zoom zero-days for macOS and Windows respectively, selling for $500,000, on April 15, 2020. Security bug brokers were selling access to Zoom security flaws that could allow remote access into users' computers. Hackers also put up over 500,000 Zoom user names and passwords for sale on the dark web. In response to the multitude of security and privacy issues found, Zoom began a comprehensive security plan, which included consulting with Luta Security, Trail of Bits, former Facebook CSO Alex Stamos, former Google global lead of privacy technology Lea Kissner, BishopFox, the NCC Group, and Johns Hopkins University cryptographer Matthew D. Green.
On April 20, 2020, the New York Times reported that Dropbox engineers had traced Zoom's security vulnerabilities back over two years, pushing Zoom to address such issues more quickly, and paying top hackers to find problems with Zoom's software. In the same article, the New York Times noted that security researchers have praised Zoom for improving its response times, and for quickly patching recent bugs and removing features that could have privacy risks. In a blog post on April 1, 2020, CEO Yuan announced a 90-day freeze on releasing new features, to focus on fixing privacy and security issues within the platform. On July 1, 2020, at the end of the freeze, the company stated it had released 100 new safety features over the 90-day period. Those efforts include end-to-end encryption for all users, turning on meeting passwords by default, giving users the ability to choose which data centers calls are routed from, consulting with security experts, forming a CISO council, an improved bug bounty program, and working with third parties to help test security. Yuan also stated that Zoom would be sharing a transparency report later in 2020.
On November 16, 2020, Zoom announced a new security feature to combat disruptions during a session. The new feature was said to be a default for all free and paid users and made available on the Zoom clients for Mac, Windows, and Linux, as well as Zoom mobile apps.
On August 12, 2022, Wired magazine reported on three separate security vulnerabilities discovered by security researcher Patrick Wardle affecting the Zoom Mac OS desktop app. The vulnerabilities allowed an attacker who already had access to the Mac device to perform a privilege escalation attack by installing malicious code using the app's auto-update feature, thereby giving them full control over the victim's device.
Zoombombing
"Zoombombing" is a phenomenon where uninvited participants join a meeting to cause disruption. In July 2019, security researcher Sam Jadali uncovered the DataSpii leak. This catastrophic leak was facilitated by a marketing intelligence company known as Nacho Analytics (NA), which provided its members access to the URLs of real-time Zoom meetings of firms such as Oracle, Dell, Walmart, Uber, UCLA and Capital One. NA's dissemination of meeting URLs enabled its members to Zoombomb these meetings. In April 2020, Zoom increased its default security settings to mitigate Zoombombing. The company also created a new "report a user to Zoom" button, intended to catch those behind Zoombombing attacks.
Encryption practices
Zoom encrypts its public data streams, using TLS 1.2 with AES-256 (Advanced Encryption Standard) to protect signaling, and AES-128 to protect streaming media. Security researchers and reporters have criticized the company for its lack of transparency and poor encryption practices. Zoom initially claimed to use "end-to-end encryption" in its marketing materials, but later clarified it meant "from Zoom end point to Zoom end point" (meaning effectively between Zoom servers and Zoom clients), which The Intercept described as misleading and "dishonest". Alex Stamos, a Zoom advisor who was formerly security chief at Facebook, noted that a lack of end-to-end encryption is common in such products, as it is also true of Google Hangouts, Microsoft Teams, and Cisco Webex. On May 7, 2020, Zoom announced that it had acquired Keybase, a company specializing in end-to-end encryption, as part of an effort to strengthen its security practices moving forward. Later that month, Zoom published a document for peer review, detailing its plans to ultimately bring end-to-end encryption to the software.
In April 2020, Citizen Lab researchers discovered that a single, server-generated AES-128 key is being shared between all participants in ECB mode, which is deprecated due to its pattern-preserving characteristics of the ciphertext. During test calls between participants in Canada and United States, the key was provisioned from servers located in mainland China where they are subject to the China Internet Security Law.
On June 3, 2020, Zoom announced that users on their free tier will not have access to end-to-end encryption so that they could cooperate with the FBI and law enforcement. Later, they said that they do not "proactively monitor meeting content". On June 17, 2020, the company reversed course and announced that free users would have access to end-to-end encryption after all.
On September 7, 2020, cryptography researcher Nadim Kobeissi accused Zoom's security team of failing to credit his open-source protocol analysis research software, Verifpal, with being instrumental during the design phase of Zoom's new encryption protocol, as described in their whitepaper published in June 2020. Kobeissi published a week's worth of conversations with Zoom's security leadership in support of his claim, including Max Krohn, which included eight Verifpal models that Zoom's team asked for feedback on, promises of a citation to credit Kobeissi for his contributions and an admission that the Verifpal citation was pulled from the whitepaper at the last moment for unspecified reasons. Kobeissi also linked to a tweet by Zoom security consultant Lea Kissner which he described as a public character assassination attempt issued in response to his repeated requests to have his work cited in the research paper published by Zoom.
Data routing
Zoom admitted that some calls in early April 2020 and prior were mistakenly routed through servers in mainland China, prompting some governments and businesses to cease their usage of Zoom. The company later announced that data of free users outside of China would "never be routed through China" and that paid subscribers will be able to customize which data center regions they want to use. The company has data centers in Europe, Asia, North America, and Latin America.
Regulatory issues
In August 2021, the Data Protection regulatory body in Hamburg, Germany, ruled that Zoom was operating in the European Union in breach of the General Data Protection Regulation (GDPR). This is due to the fact that, as per the Schrems II ruling, data that is being transferred out of the EU must be given the same protections that provided by the GDPR. The data gathered by Zoom was being sent to the United States.
See also
List of video telecommunication services and product brands
Impact of the COVID-19 pandemic on science and technology
Zoom fatigue
Zoom town
References
External links
2012 software
TvOS software
End-to-end encryption
Impact of the COVID-19 pandemic on science and technology
Internet properties established in 2012
Impact of the COVID-19 pandemic in the United States
Software associated with the COVID-19 pandemic
Videotelephony
Web conferencing
Zoom (software) | Zoom (software) | [
"Technology"
] | 4,944 | [
"History of science and technology",
"Impact of the COVID-19 pandemic on science and technology"
] |
63,435,931 | https://en.wikipedia.org/wiki/COVID-19%20drug%20development | COVID-19 drug development is the research process to develop preventative therapeutic prescription drugs that would alleviate the severity of coronavirus disease 2019 (COVID-19). From early 2020 through 2021, several hundred drug companies, biotechnology firms, university research groups, and health organizations were developing therapeutic candidates for COVID-19 disease in various stages of preclinical or clinical research (506 total candidates in April 2021), with 419 potential COVID-19 drugs in clinical trials, as of April 2021.
As early as March 2020, the World Health Organization (WHO), European Medicines Agency (EMA), US Food and Drug Administration (FDA), and the Chinese government and drug manufacturers were coordinating with academic and industry researchers to speed development of vaccines, antiviral drugs, and post-infection therapies. The International Clinical Trials Registry Platform of the WHO recorded 536 clinical studies to develop post-infection therapies for COVID-19 infections, with numerous established antiviral compounds for treating other infections under clinical research to be repurposed.
In March 2020, the WHO initiated the "SOLIDARITY Trial" in 10 countries, enrolling thousands of people infected with COVID-19 to assess treatment effects of four existing antiviral compounds with the most promise of efficacy. A dynamic, systematic review was established in April 2020 to track the progress of registered clinical trials for COVID-19 vaccine and therapeutic drug candidates.
Drug development is a multistep process, typically requiring more than five years to assure safety and efficacy of the new compound. Several national regulatory agencies, such as the EMA and the FDA, approved procedures to expedite clinical testing. By June 2021, dozens of potential post-infection therapies were in the final stage of human testing – phase III–IV clinical trials.
Background
Drug development is the process of bringing a new infectious disease vaccine or therapeutic drug to the market once a lead compound has been identified through the process of drug discovery. It includes laboratory research on microorganisms and animals, filing for regulatory status, such as via the FDA, for an investigational new drug to initiate clinical trials on humans, and may include the step of obtaining regulatory approval with a new drug application to market the drug. The entire process – from concept through preclinical testing in the laboratory to clinical trial development, including Phase I–III trials – to approved vaccine or drug normally takes more than a decade.
The term "preclinical research" is defined by laboratory studies in vitro and in vivo, indicating a beginning stage for development of a preventative vaccine, antiviral or other post-infection therapies, such as experiments to determine effective doses and toxicity in animals, before a candidate compound is advanced for safety and efficacy evaluation in humans. To complete the preclinical stage of drug development – then be tested for safety and efficacy in an adequate number of people infected with COVID-19 (hundreds to thousands in different countries) – is a process likely to require 1–2 years for COVID-19 therapies, according to several reports in early 2020. Despite these efforts, the success rate for drug candidates to reach eventual regulatory approval through the entire drug development process for treating infectious diseases is only 19%.
Phase I trials test primarily for safety and preliminary dosing in a few dozen healthy subjects, while Phase II trials – following success in Phase I – evaluate therapeutic efficacy against the COVID-19 disease at ascending dose levels (efficacy based on biomarkers), while closely evaluating possible adverse effects of the candidate therapy (or combined therapies), typically in hundreds of people. A common trial design for Phase II studies of possible COVID-19 drugs is randomized, placebo-controlled, blinded, and conducted at multiple sites, while determining more precise, effective doses and monitoring for adverse effects.
The success rate for Phase II trials to advance to Phase III (for all diseases) is about 31%, and for infectious diseases specifically, about 43%. Depending on its duration (longer more expensive) – typically a period of several months to two years – an average-length Phase II trial costs million (2013 dollars, including preclinical and Phase I costs). Successful completion of a Phase II trial does not reliably forecast that a candidate drug will be successful in Phase III research.
Phase III trials for COVID-19 involve hundreds-to-thousands of hospitalized participants, and test effectiveness of the treatment to reduce effects of the disease, while monitoring for adverse effects at the optimal dose, such as in the multinational Solidarity and Discovery trials.
Candidates
According to one source (as of August 2020), diverse categories of preclinical or early-stage clinical research for developing COVID-19 therapeutic candidates included:
antibodies (81 candidates)
antivirals (31 candidates)
cell-based compounds (34 candidates)
RNA-based compounds (6 candidates)
scanning compounds to be repurposed (18 candidates)
various other therapy categories, such as anti-inflammatory, antimalarial, interferon, protein-based, antibiotics, and receptor-modulating compounds.
Pivotal Phase III trials assess whether a candidate drug has efficacy specifically against a disease, and – in the case of people hospitalized with severe COVID-19 infections – test for an effective dose level of the repurposed or new drug candidate to improve the illness (primarily pneumonia) from COVID-19 infection. For an already-approved drug (such as hydroxychloroquine for malaria), Phase III–IV trials determine in hundreds to thousands of COVID-19-infected people the possible extended use of an already-approved drug for treating COVID-19 infection. As of August 2020, over 500 candidate therapeutics were in preclinical or a stage of Phase I–IV development, with new Phase II–III trials announced for hundreds of therapeutic candidates during 2020.
Numerous candidate drugs under study as "supportive" treatments to relieve discomfort during illness, such as NSAIDs or bronchodilators, are not included in the table below. Others in early-stage Phase II trials or numerous treatment candidates in Phase I trials, are also excluded. Drug candidates in Phase I–II trials have a low rate of success (under 12%) to pass through all trial phases to gain eventual approval. Once having reached Phase III trials, therapeutic candidates for diseases related to COVID-19 infection – infectious and respiratory diseases – have a success rate of about 72%.
Repurposed drug candidates
Drug repositioning (also called drug repurposing) – the investigation of existing drugs for new therapeutic purposes – is one line of scientific research followed to develop safe and effective COVID-19 treatments. Several existing antiviral medications, previously developed or used as treatments for Severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), HIV/AIDS, and malaria, are being researched as COVID-19 treatments, with some moving into clinical trials.
During the COVID-19 pandemic, drug repurposing is the clinical research process of rapidly screening and defining the safety and efficacy of existing drugs already approved for other diseases to be used for people with COVID-19 infection. In the usual drug development process, confirmation of repurposing for new disease treatment would take many years of clinical research – including pivotal Phase III clinical trials – on the candidate drug to assure its safety and efficacy specifically for treating COVID-19 infection. In the emergency of a growing COVID-19 pandemic, the drug repurposing process was being accelerated during March 2020 to treat people hospitalized with COVID-19.
Clinical trials using repurposed, generally safe, existing drugs for hospitalized COVID-19 people may take less time and have lower overall costs to obtain endpoints proving safety (absence of serious side effects) and post-infection efficacy, and can rapidly access existing drug supply chains for manufacturing and worldwide distribution. In an international effort to capture these advantages, the WHO began in mid-March 2020 expedited international Phase II–III trials on four promising treatment options – the SOLIDARITY trial – with numerous other drugs having potential for repurposing in different disease treatment strategies, such as anti-inflammatory, corticosteroid, antibody, immune, and growth factor therapies, among others, being advanced into Phase II or III trials during 2020.
In March 2020, the United States Centers for Disease Control and Prevention (CDC) issued a physician advisory concerning remdesivir for people hospitalized with pneumonia caused by COVID-19: "While clinical trials are critical to establish the safety and efficacy of this drug, clinicians without access to a clinical trial may request remdesivir for compassionate use through the manufacturer for patients with clinical pneumonia."
Novel antibody drugs
Convalescent plasma
Passive immunization with convalescent plasma or hyperimmune serum has been proposed as a potential treatment for COVID-19. As of May 2021, there is strong evidence that convalescent plasma treatment is not associated with clinical improvements for people with moderate or severe disease and does not decrease the risk of dying. The potential for adverse effects associated with convalescent plasma treatment is unknown.
In the United States, the FDA has granted temporary authorization to convalescent plasma (plasma from the blood of people who have recovered from COVID-19, which thus contains antibodies against SARS-CoV-2) as an experimental treatment in cases where the person's life is seriously or immediately threatened. As of May 2021, at least 12 randomized controlled trials on the effectiveness of convalescent plasma treatment were published in peer-reviewed medical journals. In addition, as of May 2021, 100 additional trials were 'ongoing' and 33 studies were reported as 'competed' but not yet published.
Argentina, Brazil, Costa Rica, and Mexico have pursued development of antisera. Brazil began development of an equine hyperimmune serum, obtained by inoculating horses with recombinant SARS-CoV-2 spike protein, in mid-2020. A consortium of Instituto Vital Brazil, UFRJ, the Oswaldo Cruz Foundation and the D'Or Institute for Research and Education in Rio de Janeiro began preclinical trials in May 2020, while Instituto Butantan in São Paulo completed animal testing in September. In December 2020, Argentina granted emergency authorization to CoviFab, a locally developed formulation of equine hyperimmune serum, for use in cases of moderate to severe COVID-19, based on the initial results of a single phase 2/3 trial which suggested reductions in mortality, ICU admission, and mechanical ventilation requirements in patients who received the serum. This was harshly criticized by the Argentine Intensive Care Society, which stated that the trial failed to achieve its primary or secondary endpoints and did not demonstrate any statistically significant differences between the serum and placebo groups.
Bamlanivimab/etesevimab
Bebtelovimab
Casirivimab/imdevimab
Pemivibart
Regdanvimab
Sotrovimab
Tixagevimab/cilgavimab
Vilobelimab
Novel viral replication inhibitors
Molnupiravir
Novel protease inhibitors
Ensitrelvir
Nirmatrelvir/ritonavir
Other
Sabizabulin
Planning and coordination
Early planning
Over 2018–20, new initiatives to stimulate vaccine and antiviral drug development included partnerships between governmental organizations and industry, such as the European Innovative Medicines Initiative, the US Critical Path Initiative to enhance innovation of drug development, and the Breakthrough Therapy designation to expedite development and regulatory review of promising candidate drugs. To accelerate refinement of diagnostics for detecting COVID-19 infection, a global diagnostic pipeline tracker was formed.
According to a tracker of clinical trial progress on potential therapeutic drugs for COVID-19 infections, 29 Phase II–IV efficacy trials were concluded in March 2020 or scheduled to provide results in April from hospitals in China – which experienced the first outbreak of COVID-19 in late 2019. Seven trials were evaluating repurposed drugs already approved to treat malaria, including four studies on hydroxychloroquine or chloroquine phosphate. Repurposed antiviral drugs make up most of the Chinese research, with 9 Phase III trials on remdesivir across several countries due to report by the end of April. Other potential therapeutic candidates under pivotal clinical trials concluding in March–April are vasodilators, corticosteroids, immune therapies, lipoic acid, bevacizumab, and recombinant angiotensin-converting enzyme 2, among others.
The COVID-19 Clinical Research Coalition has goals to 1) facilitate rapid reviews of clinical trial proposals by ethics committees and national regulatory agencies, 2) fast-track approvals for the candidate therapeutic compounds, 3) ensure standardised and rapid analysis of emerging efficacy and safety data, and 4) facilitate sharing of clinical trial outcomes before publication. A dynamic review of clinical development for COVID-19 vaccine and drug candidates was in place, as of April.
By March 2020, the international Coalition for Epidemic Preparedness Innovations (CEPI) committed to research investments of US$100 million across several countries, and issued an urgent call to raise and rapidly invest $2 billion for vaccine development. Led by the Bill and Melinda Gates Foundation with partners investing million and coordinating with the World Health Organization, the COVID-19 Therapeutics Accelerator began in March, facilitating drug development researchers to rapidly identify, assess, develop, and scale up potential treatments. The COVID-19 Clinical Research Coalition formed to coordinate and expedite results from international clinical trials on the most promising post-infection treatments. In early 2020, numerous established antiviral compounds for treating other infections were being repurposed or developed in new clinical research efforts to alleviate the illness of COVID-19.
During March 2020, the Coalition for Epidemic Preparedness Innovations (CEPI) initiated an international COVID-19 vaccine development fund, with the goal to raise for vaccine research and development, and committed to investments of in vaccine development across several countries. The Canadian government announced in funding for 96 research projects on medical countermeasures against COVID-19, including numerous vaccine candidates at Canadian universities, with plans to establish a "vaccine bank" of new vaccines for implementation if another COVID-19 outbreak occurs. The Bill & Melinda Gates Foundation invested 150 million in April for development of COVID-19 vaccines, diagnostics, and therapeutics.
Computer-assisted research
In March 2020, the United States Department of Energy, National Science Foundation, NASA, industry, and nine universities pooled resources to access supercomputers from IBM, combined with cloud computing resources from Hewlett Packard Enterprise, Amazon, Microsoft, and Google, for drug discovery. The COVID-19 High Performance Computing Consortium also aims to forecast disease spread, model possible vaccines, and screen thousands of chemical compounds to design a COVID-19 vaccine or therapy. The Consortium used up 437 petaFLOPS of computing power by May 2020.
The C3.ai Digital Transformation Institute, an additional consortium of Microsoft, six universities (including the Massachusetts Institute of Technology, a member of the first consortium), and the National Center for Supercomputer Applications in Illinois, working under the auspices of C3.ai, an artificial intelligence software company, are pooling supercomputer resources toward drug discovery, medical protocol development and public health strategy improvement, as well as awarding large grants to researchers who proposed by May to use AI to carry out similar tasks.
In March 2020, the distributed computing project Folding@home launched a program to assist drug developers, initially simulating protein targets from SARS-CoV-2 and the related SARS-CoV virus, which has been studied previously.
Distributed computing project Rosetta@home also joined the effort in March. The project uses computers of volunteers to model SARS-CoV-2 virus proteins to discover possible drug targets or create new proteins to neutralize the virus. Researchers revealed that with the help of Rosetta@home, they had been able to "accurately predict the atomic-scale structure of an important coronavirus protein weeks before it could be measured in the lab."
In May 2020, the OpenPandemics – COVID-19 partnership between Scripps Research and IBM's World Community Grid was launched. The partnership is a distributed computing project that "will automatically run a simulated experiment in the background [of connected home PCs] which will help predict the effectiveness of a particular chemical compound as a possible treatment for COVID-19".
International Solidarity and Discovery Trials
In March, the World Health Organization (WHO) launched the coordinated "Solidarity Trial" in 10 countries on five continents to rapidly assess in thousands of COVID-19 infected people the potential efficacy of existing antiviral and anti-inflammatory agents not yet evaluated specifically for COVID-19 illness. By late April, hospitals in over 100 countries were involved in the trial.
The individual or combined drugs undergoing initial studied are 1) lopinavir–ritonavir combined, 2) lopinavir–ritonavir combined with interferon-beta, 3) remdesivir or 4) (hydroxy)chloroquine in separate trials and hospital sites internationally. Following a study published by The Lancet on safety concerns with hydroxychloroquine, the WHO suspended use of it from the Solidarity trial in May 2020, reinstated it after the research was retracted, then abandoned further use of the drug for COVID-19 treatment when analysis showed in June that it provided no benefit.
With about 15% of people infected by COVID-19 having severe illness, and hospitals being overwhelmed during the pandemic, WHO recognized a rapid clinical need to test and repurpose these drugs as agents already approved for other diseases and recognized as safe. The Solidarity project is designed to give rapid insights to key clinical questions:
Do any of the drugs reduce mortality?
Do any of the drugs reduce the time a patient is hospitalized?
Do the treatments affect the need for people with COVID-19-induced pneumonia to be ventilated or maintained in intensive care?
Could such drugs be used to minimize the illness of COVID-19 infection in healthcare staff and people at high risk of developing severe illness?
Enrolling people with COVID-19 infection is simplified by using data entries, including informed consent, on a WHO website. After the trial staff determines the drugs available at the hospital, the WHO website randomizes the hospitalized subject to one of the trial drugs or to the hospital standard of care for treating COVID-19. The trial physician records and submits follow-up information about the subject status and treatment, completing data input via the WHO Solidarity website. The design of the Solidarity trial is not double-blind – which is normally the standard in a high-quality clinical trial – but the WHO needed speed with quality for the trial across many hospitals and countries. A global safety monitoring board of WHO physicians examine interim results to assist decisions on safety and effectiveness of the trial drugs, and alter the trial design or recommend an effective therapy. A similar web-based study to Solidarity, called "Discovery", was initiated in March across seven countries by INSERM (Paris, France).
The Solidarity trial seeks to implement coordination across hundreds of hospital sites in different countries – including those with poorly-developed infrastructure for clinical trials – yet needs to be conducted rapidly. According to John-Arne Røttingen, chief executive of the Research Council of Norway and chairman of the Solidarity trial international steering committee, the trial would be considered effective if therapies are determined to "reduce the proportion of patients that need ventilators by, say, 20%, that could have a huge impact on our national health-care systems."
During March, funding for the Solidarity trial reached million from 203,000 individuals, organizations and governments, with 45 countries involved in financing or trial management.
A clinical trial design in progress may be modified as an "adaptive design" if accumulating data in the trial provide early insights about positive or negative efficacy of the treatment. The global Solidarity and European Discovery trials of hospitalized people with severe COVID-19 infection apply adaptive design to rapidly alter trial parameters as results from the four experimental therapeutic strategies emerge. Adaptive designs within ongoing Phase II–III clinical trials on candidate therapeutics may shorten trial durations and use fewer subjects, possibly expediting decisions for early termination or success, and coordinating design changes for a specific trial across its international locations.
Adaptive COVID-19 Treatment Trial
The US National Institute of Allergy and Infectious Diseases (NIAID) initiated an adaptive design, international Phase III trial (called "ACTT") to involve up to 800 hospitalized COVID-19 people at 100 sites in multiple countries. Beginning with use of remdesivir as the primary treatment over 29 days, the trial definition of its adaptive protocol states that "there will be interim monitoring to introduce new arms and allow early stopping for futility, efficacy, or safety. If one therapy proves to be efficacious, then this treatment may become the control arm for comparison(s) with new experimental treatment(s)."
Operation Warp Speed
RECOVERY Trial
A large-scale, randomized controlled trial named the RECOVERY Trial was set up in March 2020, in the UK to test possible treatments for COVID-19. It is run by the Nuffield Departments of Public Health and of Medicine at the University of Oxford and is testing five repurposed drugs and also convalescent plasma. The trial enrolled more than 11,500 COVID-19 positive participants in the U.K by June 2020.
During April, the British RECOVERY (Randomised Evaluation of COVid-19 thERapY) trial was launched initially in 132 hospitals across the UK, expanding to become one of the world's largest COVID-19 clinical studies, involving 5400 infected people under treatment at 165 UK hospitals, as of mid-April. The trial is examining different potential therapies for severe COVID-19 infection: lopinavir/ritonavir, low-dose dexamethasone (an anti-inflammatory steroid), hydroxychloroquine, and azithromycin (a common antibiotic). In June, the trial arm using hydroxychloroquine was discontinued when analyses showed it provided no benefit.
On 16 June the trial group released a statement that dexamethasone had been shown to reduce mortality in patients receiving respiratory support. In a controlled trial around 2,000 hospital patients were given dexamethasone and were compared with more than 4,000 who did not receive the drug. For patients on ventilators, it cut the risk of death from 40% to 28% (1 in 8). For patients needing oxygen, it cut the risk of death from 25% to 20% (1 in 5).
By the end of June 2020, the trial had published findings regarding hydroxychloroquine and dexamethasone. It had also announced results for lopinavir/ritonavir which were published in October 2020. The lopinavir-ritonavir and hydroxychloroquine arms were closed to new entrants after being shown to be ineffective. Dexamethasone was closed to new adult entries after positive results and by November 2020, was open to child entries.
PANORAMIC trial
Launched in December 2021, the PANORAMIC trial will test the effectiveness of molnupiravir and nirmatrelvir/ritonavir in preventing hospitalisation and helping faster recovery for people aged over 50 and those at higher risk due to underlying health conditions. PANORAMIC is sponsored by the University of Oxford and funded by the National Institute for Health Research (NIHR). As of March 2022 has over 16,000 people enrolled as participants making it the largest study into COVID-19 antivirals.
See also
Cost of drug development
COVID Moonshot
References
Further reading
External links
R&D Blueprint and COVID-19, World Health Organization
Coronaviruses by US National Institute for Allergy and Infectious Diseases
COVID-19 therapeutics tracker Regulatory Affairs Professionals Society
Anti-influenza agents
Clinical research
Drug discovery
Drugs
Drug development
Vaccines | COVID-19 drug development | [
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"Vaccination",
"Drugs"
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76,476,481 | https://en.wikipedia.org/wiki/Plogoff%20nuclear%20power%20plant%20project | The Plogoff nuclear power plant project was an EDF project to build a nuclear power plant in the commune of Plogoff in Finistère, Brittany. Popular mobilization against the project between 1978 and 1981 led to its abandonment. This anti-nuclear movement was part of a period marked by the birth of political ecology worldwide.
Plogoff site
Plogoff is a commune in Basse-Bretagne, near the Pointe du Raz in Finistère. The nuclear power plant would have been located on the edge of Audierne Bay.
Chronology of events
In response to the first oil crisis in October 1973, the first Pierre Messmer government accelerated the civil nuclear program, and on March 5, 1974, launched an ambitious program of 13 900-megawatt units over six years (at an estimated cost of 13 billion francs), with plans to build 200 power plants in France by 2000.
In 1975, the General Councils and the Economic and Social Council agreed in principle to build a nuclear power plant in Brittany on 167 hectares of Breton moorland (4 generating units of 1,300 MW each, for a total capacity of 5,200 MW). Five sites have been identified for prospecting in Brittany: Beg an Fry in Guimaëc, Ploumoguer, Plogoff (near Pointe du Raz), Saint-Vio in Tréguennec and Erdeven. In June 1976, EDF engineers began drilling the first exploratory boreholes, triggering the first major reactions from the local population, which until then had been largely uninformed. The mobilization in Erdeven and Ploumoguer was such that these sites were quickly ruled out.
A defense committee was formed on June 6, at the initiative of the mayor of Plogoff, Jean-Marie Kerloch. On June 8, Plogoffites set up barricades at the entrance to their commune for three days, as EDF geologists and technicians were forced to give way. On September 11, 1978, this committee decided to create a GFA (based on the Larzac model) to make expropriation procedures more difficult6. Despite the structuring of the anti-nuclear movement, notably through CLINs and CRINs, the Plogoff site was selected on September 12 and 25, 1978 by the Conseil économique et social de Bretagne and the Conseil général du Finistère. On November 29, 1978, the General Council of Finistère voted 28 to 17 in favor of building a nuclear power plant at Plogoff, marking the end of the period of the "strolling power plant".
Citizen opposition continued unabated: in early May 1979, the defense committee decided to install the Feunteun-Aod alternative sheepfold on the GFA. On January 30, 1980, the files for the public utility inquiry were received at Plogoff town hall, where they were burnt that very afternoon. The prefectural authorities responded by hiring vans to act as "annex town halls" (protected by gendarmes) to gather the population's favorable opinions, so that the public utility inquiry could begin on January 31, 1980.
During the public inquiry, a free radio station - Radio Plogoff - began broadcasting. It broadcast radio programs until the Socialist victory in 1981.
After the public inquiry, demonstrations took place, leading to sometimes violent clashes with the CRS. On several occasions, demonstrators were arrested and put on trial for damaging public buildings and throwing projectiles, with the struggle now seen as a battle of "stones against guns".
On March 16, 1980, 50,000 people demonstrated to mark the closure of the public utility inquiry. On May 24, 1980, 100 to 150,000 demonstrators celebrated the end of the procedure, with 50 to 60,000 staying on for the fest-noz that brought the festivities to a close.
On April 9, 1981, at his rally in Brest, candidate François Mitterrand declared that Plogoff "does not figure, nor will it figure" in the nuclear plan he would implement if elected. In keeping with his campaign promise, the press release of June 3, 1981, issued after the Council of Ministers of President Mitterrand's Mauroy government, confirmed the abandonment of plans to extend the Larzac military camp and build the Plogoff nuclear power plant. Instead, two coal-fired units, each rated at 600 MW, were added to the Cordemais power plant in 1983 and 1984. A 446 MW gas-fired combined-cycle power plant in the commune of Landivisiau, in the north of the Finistère département, goes into production on March 31, 2022.
The Plogoff women
Women played a particularly important role in this mobilization. Many were seamen's wives, and therefore often single homemakers. Along with young people and pensioners, they are the most present in the village and very active in this struggle.
When the vans, protected by mobile guards, were set up to act as a town hall annex, the women began a war of nerves with the gendarmes. During the six weeks of the public inquiry, they mobilized daily, spending hours and sometimes days in front of the guards, talking to them and sometimes discouraging the younger ones. At 5 p.m., as the women leave the town halls, they are joined by men and anti-nuclear activists from the region. This "five o'clock mass" often takes a more violent turn, involving the use of Molotov cocktails, with the gendarmes retaliating with offensive grenades.
During the clashes, women were also in the front ranks, blocking the way of the gendarmes. They included Annie Carval, now president of the defense committee (in place of Jean-Marie Kerloc'h, who was accused of allowing himself to be influenced by EDF), and Amélie Kerloc'h, first deputy and then mayor of the commune. The latter encouraged residents to block access to Plogoff to make it "an island inaccessible to the police".
A film, Plogoff, des pierres contre des fusils, recounts the events and shows the mobilization of the women, who harassed the young mobile guards every day, causing several of them to break down. At the head of the Plogoff mobilization are Amélie Kerloc'h, Plogoff's first deputy mayor, who is seen in the film urging outraged demonstrators to "make Plogoff an island", and Annie Carval, president of the defense committee. Plogoff, des pierres contre des fusils was directed by Nicole Le Garrec, with Félix Le Garrec as a cinematographer and Jakez Bernard as a sound technician. Released in November 1980 (before the project was abandoned), the film was restored in 2019 and selected for Cannes Classics 2019 (the Cannes Film Festival's selection of heritage films). It was re-released in cinemas on February 12.
A book entitled Femmes de Plogoff (Women of Plogoff) has been published by Renée Conan and Annie Laurent. In it, they recount how they learned to fight, the violence they had to face, The changes in their family lives during this time, the courage they showed, and the connections they forged with each other and with other struggles elsewhere.
A show based on the book was staged by Laëtitia Rouxel (drawing), Brigitte Stanislas (reading), and Patrice Paichereau (music).
Law enforcement
Seven squadrons of mobile gendarmes were stationed in Pont-Croix and Loctudy, and intervened in Plogoff. Gendarmes-parachutistes were deployed as reinforcements.
The mobile gendarmes sometimes use wheeled armored vehicles at Plogoff. A helicopter watched over the demonstrators. It was there to protect the movement of the annexed city halls. Military engineering vehicles from Angers were mobilized to breach the barricades.
In terms of weaponry, incapacitating grenades were used in large numbers, including "instant tear-gas grenades" (tolite + CS gas) (e.g. 85 on Friday, March 14, the last day of the public inquiry). Ethyl bromoacetate, although banned, seems to have been used by urban police during riots in Quimper, who are said to have disposed of old stocks.
Consequences
Following a major mobilization, the project was abandoned, a first in France. The previous year, a demonstration at Creys-Malville had had tragic consequences: one demonstrator was killed, and many others injured, including a mobile guard whose hand was torn off. Parallel to this action, demonstrations occurred at Le Pellerin, near Nantes, where another nuclear power plant was planned. This was abandoned in 1983, as promised by Socialist candidate François Mitterrand, before being replaced by another project, the Le Carnet nuclear power plant, also abandoned in 1997.
Posterity
The Tri Yann music group, opposed to the project, wrote the eponymous song for the album An heol a zo glaz, released in 1981. Kan ar kann (Breton for "song of combat") describes the struggle of the people of Plogoff to oppose the construction of a nuclear power plant.
The Iroise Marine Natural Park was created by decree on September 28, 2007. Covering an area of 3,500 km2, it is likely to be extended, with a proposal to the communes of Cap Sizun (of which Plogoff is a part) to involve them in decision-making and take into account the ecological and socio-economic coherence of the professional and leisure activity basins.
On April 22, 2021, France 3 broadcast the film Plogoff, les révoltés du nucléaire (2021, France, 55 minutes) by François Reinhardt.
See also
Timeline of history of environmentalism
Brennilis Nuclear Power Plant
Plogoff
References
Notes
Bibliography
7
Documentaries
1980: Plogoff, des pierres contre des fusils, Nicole Le Garrec (France, 112 minutes), theatrical feature documentary. The restored film has been selected for the 2019 Cannes Film Festival (Cannes Classics).
1980: Le Dossier Plogoff, François Jacquemain (France, 50 minutes), restored in 2018 by Synaps.
2000: L'affaire Plogoff (France, 52 minutes), Brigitte Chevet.
2018: Plogoff mon amour, mémoire d'une lutte, Dominique Agniel (France, 60 minutes).
2021: Plogoff, les révoltés du nucléaire, François Reinhardt (France, 55 minutes).
External links
Plogoff, un moment d’écologie populaire
Plogoff, 30 ans après
Plogoff, chronique de la lutte
Plogoff, mémoire d'une lutte | Lutte antiucléaire | Bretagne
Hervé Thomas, 40 ans déjà!
Nuclear power
Nuclear power in France
Nuclear power by country
Nuclear power stations in France | Plogoff nuclear power plant project | [
"Physics"
] | 2,288 | [
"Power (physics)",
"Physical quantities",
"Nuclear power"
] |
76,476,945 | https://en.wikipedia.org/wiki/NGC%201220 | NGC 1220 is a young compact open cluster in the constellation Perseus. It was discovered by John Herschel in 1831.
The cluster is located at = 143.04°, = −3.96° in the galactic coordinate system, and is 120 parsecs above the galactic plane. It is approximately 6m 42s east and 10′ 12″ south from the nearest visible star, γ Persei.
NGC 1220 consists of approximately 26 stars with spectral types between A0 and B9, although the majority fall between A5 and B5.
Notes
References
Open clusters
Perseus (constellation)
1220
Astronomical objects discovered in 1831
Discoveries by John Herschel | NGC 1220 | [
"Astronomy"
] | 137 | [
"Perseus (constellation)",
"Constellations"
] |
76,478,062 | https://en.wikipedia.org/wiki/Knuth%E2%80%93Plass%20line-breaking%20algorithm | The Knuth–Plass algorithm is a line-breaking algorithm designed for use in Donald Knuth's typesetting program TeX. It integrates the problems of text justification and hyphenation into a single algorithm by using a discrete dynamic programming method to minimize a loss function that attempts to quantify the aesthetic qualities desired in the finished output.
The algorithm works by dividing the text into a stream of three kinds of objects: boxes, which are non-resizable chunks of content, glue, which are flexible, resizeable elements, and penalties, which represent places where breaking is undesirable (or, if negative, desirable). The loss function, known as "badness", is defined in terms of the deformation of the glue elements, and any extra penalties incurred through line breaking.
Making hyphenation decisions follows naturally from the algorithm, but the choice of possible hyphenation points within words, and optionally their preference weighting, must be performed first, and that information inserted into the text stream in advance. Knuth and Plass' original algorithm does not include page breaking, but may be modified to interface with a pagination algorithm, such as the algorithm designed by Plass in his PhD thesis.
Typically, the cost function for this technique should be modified so that it does not count the space left on the final line of a paragraph; this modification allows a paragraph to end in the middle of a line without penalty. The same technique can also be extended to take into account other factors such as the number of lines or costs for hyphenating long words.
Computational complexity
A naive brute-force exhaustive search for the minimum badness by trying every possible combination of breakpoints would take an impractical time. The classic Knuth-Plass dynamic programming approach to solving the minimization problem is a worst-case algorithm but usually runs much faster in close to linear time.
Solving for the Knuth-Plass optimum can be shown to be a special case of the convex least-weight subsequence problem, which can be solved in time. Methods to do this include the SMAWK algorithm.
Simple example of minimum raggedness metric
For the input text
AAA BB CC DDDDD
with line width 6, a greedy algorithm that puts as many words on a line as possible while preserving order before moving to the next line, would produce:
------ Line width: 6
AAA BB Remaining space: 0
CC Remaining space: 4
DDDDD Remaining space: 1
The sum of squared space left over by this method is . However, the optimal solution achieves the smaller sum :
------ Line width: 6
AAA Remaining space: 3
BB CC Remaining space: 1
DDDDD Remaining space: 1
The difference here is that the first line is broken before BB instead of after it, yielding a better right margin and a lower cost 11.
References
External links
Breaking Paragraphs into Lines, the original paper by Knuth and Plass
Algorithms
Typography | Knuth–Plass line-breaking algorithm | [
"Mathematics"
] | 619 | [
"Algorithms",
"Mathematical logic",
"Applied mathematics"
] |
76,479,633 | https://en.wikipedia.org/wiki/NGC%202911 | NGC 2911 is a peculiar lenticular galaxy in the constellation Leo. The galaxy lies about 145 million light years away from Earth, which means, given its apparent dimensions, that NGC 2911 is approximately 165,000 light years across. It was discovered by William Herschel on March 11, 1784.
The galaxy features dust lanes. The kinematic axis of the molecular gas of the galaxy isn't aligned with the stellar one, indicating it is of external origin. The nucleus of the galaxy has been found to be active and it is categorised as a type 2 LINER. The most accepted theory for the energy source of active galactic nuclei is the presence of an accretion disk around a supermassive black hole. The supermassive black hole in the nucleus of NGC 5953 is estimated to have a mass of based on stellar velocity dispersion. A one-sided jet measuring about half parsec in length is visible in radiowaves.
NGC 2911 is the foremost member of a galaxy group known as NGC 2911 group or LGG 177. Other members of the group include the galaxies NGC 2912, NGC 2913, NGC 2914, and NGC 2939. NGC 2912 lies at a distance of 1.3 arcminutes while NGC 2914 lies at a distance of 4.8 arcminutes. NGC 2919 appears next to the group but it isn't a member of it. A bit further away from the NGC 2911 group lies NGC 2872 and its group, the UGC 5189 group and the CGCG 063-066 group.
Gallery
See also
NGC 1947 - a similar galaxy
References
External links
Unbarred lenticular galaxies
Peculiar galaxies
LINER galaxies
Leo (constellation)
2911
05092
232
27159
Discoveries by William Herschel
Astronomical objects discovered in 1784
+02-25-003 | NGC 2911 | [
"Astronomy"
] | 382 | [
"Leo (constellation)",
"Constellations"
] |
76,482,605 | https://en.wikipedia.org/wiki/Maria%20Am%C3%A9lia%20Chaves | Maria Amélia de Sousa Ferreira Chaves de Almeida Fernandes (28 January 1911 – 5 April 2017) was a Portuguese civil engineer. She was the first female civil engineer to graduate from the Instituto Superior Técnico of the Universidade Técnica de Lisboa. She is considered to be the first Portuguese woman to graduate and then work in civil engineering, and the first Portuguese female engineer to work in the field.
Early life
Maria Amélia de Sousa Ferreira Chaves was born in São Jorge de Arroios, Lisbon on 28 January 1911, the daughter of General João Carlos Pires Ferreira Chaves, a military commander and engineer. She had a brother Fernando de Sousa Ferreira Chaves. She was the niece of the engineer Raul Pires Ferreira Chaves, Maria Alexandrina Pires Ferreira Chaves and early Portuguese military pilot Olímpio Ferreira Chaves. She spent two years in India between 1927 and 1927 when her father was Chief of Staff of the Portuguese Army there. On her return she taught in a school to save money for her college education.
Education
At the age of 20, Maria Amélia Chaves entered the Instituto Superior Técnico of the Universidade Técnica de Lisboa in 1931. She studied on the general technical course, the first two years were on general technical subjects, with students choosing a specialism in the third year. She was expected to choose chemistry, as it was considered more suitable for a woman, but opted for the civil engineering course, which challenged social norms of the time. Chaves graduated with a degree in civil engineering in 1937.
Career
After a traineeship with the company run by engineer and later politician Eduardo Arantes e Oliveira, Chaves joined the staff of Lisbon City Council. It was unusual for a woman to work in civil engineering at the time, even more so to work outside the office and go into the field to supervise works on site. Chaves designed and had made a special trouser-skirt, so she could climb scaffolding without issue. She developed good working relationships with and become respected by the workers on site. However, she felt constantly restricted by her superiors, and resigned from the council in the 1940s.
Chaves set up as an independent contractor and never stopped working in the construction industry. She was an innovator and undertook the first anti-seismic building tests carried out in Portugal, which she presented in two papers at the First Symposium on Earthquakes, held in Lisbon in 1955: "Economic aspect of the consideration of the action of earthquakes in the design of buildings" and "The collaboration of engineer and architect in the design of anti-seismic constructions". She was the engineer on the Escola Industrial e Comercial de Oliveira de Azeméis (Industrial and Commercial School) from 1959 to 1963. When she was nearly ninety years old she carried out her last anti-seismic tests, for the building where she lived.
In 1938, she was the first woman to join the Order of Engineers, and was its dean in 2012. She was the first woman to sign projects and follow their execution to the end.
Honours
She was honoured by her alma mater Instituto Superior Técnico in 2011, during a ceremony that brought together the first women in Técnico's history.
Personal life
She married aged 28, to General Afonso Pinto de Magalhães Galvão Mexia de Almeida Fernandes, who was also an engineer.
References
1911 births
2017 deaths
Portuguese civil engineers
Instituto Superior Técnico alumni
People from Lisbon
Women engineers
20th-century women engineers
Portuguese women engineers
Civil engineers
Portuguese women centenarians | Maria Amélia Chaves | [
"Engineering"
] | 732 | [
"Civil engineering",
"Civil engineers"
] |
76,483,934 | https://en.wikipedia.org/wiki/2023%20El%20Palito%20oil%20spill | An oil spill occurred December 2023 at the El Palito refinery in Puerto Cabello, Venezuela.
Spill
The oil spill occurred at the end of December 2023 on the coast of the Carabobo state, affecting the beach of Puerto Cabello. Days later, the National Union of Press Workers (SNTP) denounced that officials of the General Directorate of Military Counterintelligence (DGCIM) had prohibited the reporting of the incident.
See also
2020 El Palito oil spill
MV Wakashio oil spill
Amuay tragedy
Orinoco Mining Arc
References
PDVSA
2023 disasters in South America
2023 in Venezuela
Oil spills in South America
Oil spills
Carabobo
December 2023 events in Venezuela | 2023 El Palito oil spill | [
"Chemistry",
"Environmental_science"
] | 148 | [
"Oil spills",
"Water pollution"
] |
76,484,106 | https://en.wikipedia.org/wiki/NGC%201947 | NGC 1947 is a peculiar lenticular galaxy in the constellation Dorado. The galaxy lies about 50 million light years away from Earth, which means, given its apparent dimensions, that NGC 1947 is approximately 75,000 light years across. It was discovered by James Dunlop on November 5, 1826.
Characteristics
The galaxy is characterised by the presence of dust lanes across the minor axis of the galaxy, indicating it is a polar-ring galaxy. The galaxy has one central dust lane while three more less pronounced lanes are visible which look like concentric rings. Although it is categorised as a lenticular galaxy, it lacks a disk, having thus more in common with elliptical galaxies.
Molecular gas has been detected around the nucleus of the galaxy with an estimated hydrogren mass of . The gas rotates in an axis perpendicular to that of the stars of the galaxy, but in its inner region it is warped. The kinematics suggest that the dust and gas have an external origin, probably accreted from a gas-rich galaxy, as there is a lack of tidal tails that would indicate it is as a result of an unequal mass merger with a disk galaxy.
The nucleus of the galaxy has been found to be active and it is categorised as a LINER. The most accepted theory for the energy source of active galactic nuclei is the presence of an accretion disk around a supermassive black hole.
Nearby galaxies
NGC 1947 is the brightest galaxy in the NGC 1947 group, which also includes the galaxies ESO 085–065, ESO 085–088, and ESO 086–010. This group lies close to the Dorado Group, and is part of the Southern Supercluster.
References
External links
Lenticular galaxies
Polar-ring galaxies
Peculiar galaxies
Dorado
NGC 1947 Group
1947
17296
Discoveries by James Dunlop
Astronomical objects discovered in 1826
085-G87
05264-6347 | NGC 1947 | [
"Astronomy"
] | 392 | [
"Dorado",
"Constellations"
] |
76,488,286 | https://en.wikipedia.org/wiki/Livable%20California | Livable California is a NIMBY group in California known for advocating against increased housing supply and for local control. The organization disputes the existence of the California housing shortage. The organization was founded by Marin County-based activist Susan Kirsch.
Livable California was founded in 2018 by Marin County-based activist and former teacher Susan Kirsch and former oil and gas executive Rick Hall of San Francisco. They organized in opposition to Senator Scott Wiener’s housing development bill SB 827, helping to defeat it. The group also opposed subsequent iterations of the bill, such as SB 50, which would permit fourplexes in most neighborhoods exclusively zoned for single-family housing and mid-rises near public transit stations.
Susan Kirsch started in anti-housing activism when she successfully prevented a 20-unit apartment building in her neighborhood. Kirsch self-describes as a proponent for "slow growth", and disputes that California is experiencing a housing crisis. Other members of Livable California describe themselves as proponents for "sensible" development, "smart growth" or "preservationists". What unifies Livable California members is opposition to high-density housing development and support for single-family-exclusive zoning.
Susan Kirsch left the board of Livable California in 2019.
References
Housing
Political movements
Urban planning | Livable California | [
"Engineering"
] | 267 | [
"Urban planning",
"Architecture"
] |
76,492,169 | https://en.wikipedia.org/wiki/Eli%20Jerby | Eliahu (Eli) Jerby (Hebrew: אלי ג'רבי; born June 22, 1957) is a full professor at the Iby and Aladar Fleischman Faculty of Engineering, Tel Aviv University (TAU). His studies deal with localized interactions between electromagnetic (EM) radiation and materials in various phases. These include solids, powders, and plasmas, and their phase transitions. He also develops applications for these phenomena in the microwave regime.
Biography
Jerby graduated in 1979 with bachelor's and master's degrees in electrical engineering at Tel Aviv University. His PhD thesis (1988) introduced a 3D linear theory of free-electron lasers (FELs). He did his post-doc as a Fulbright and Rothschild Fellow in the laboratory of Prof. George Bekefi at the Massachusetts Institute of Technology (MIT). Since 1991 he has been a faculty member at TAU’s Faculty of Engineering.
Research
Jerby’s early studies dealt with amplification mechanisms of EM waves by electron beams in vacuum. These include fast-wave interactions (e.g. cyclotron-resonance masers, gyrotrons, and FELs), and their synergistic combination with slow waves in periodic structures (of 1, 2 or 3 dimensions known now as metamaterials). His FEL devices, operating at extremely low voltages, and accordingly in the UHF range, marked a record for the longest FEL’s wavelength. His other innovative FEL schemes were further investigated by T. C. Marshal (FEL angular steering), H. P. Freund (slow-wave ubitron), and others.
Jerby’s more recent team research deals with hotspot phenomena created by localized microwave-heating (LMH) processes. The intentional LMH effect discovered in these studies provided the basis for the microwave-drill invention, which aroused media interest worldwide. Microwave drills have since been successfully developed in various materials, including glass, concrete, and metals, and for a variety of applications.
Operating a microwave-drill device in an inverse mode causes the molten hotspot to detach from the substrate material. Further irradiation of the melt causes its vaporization in the form of a plasma column. In certain operating conditions, this plasma converges into a form of a plasma ball floating in the air. Similar experiments were followed by K. D. Stephan and other researchers. It was found later that the LMH-generated plasma also contains charged particles in nanometric and micrometric sizes, which originate from the substrate material. These add to the ions and electrons in the plasma, hence defined as dusty plasma. The similarity between these laboratory-made plasma balls and the relatively rare phenomenon of ball lightning in nature enables mimicking this natural atmospheric phenomenon in the laboratory. Similar experiments also demonstrate various volcanic phenomena, such as the flow of hot lava from the molten core of a basalt rock. These findings have also attracted media attention.
Other studies by Jerby’s group include novel LMH phenomena and applications, such as igniting thermite mixtures (led to the discovery of the bubble-marble effect), and 3D-printing of metal powders. Jerby’s developments contributed to the trend of using high-power transistors for microwave heating applications.
Jerby served as the Editor of the Journal of Microwave Power and Electromagnetic Energy (JMPEE) in 2006-2009, and of AMPERE Newsletter (2015-2017). He also participated in organizing international conferences in his various research fields. Besides his scientific publications, he also authored several opinion articles related to academia-and-society issues in Israel.
References
External links
Official website of Eli Jerby
Eli Jerby at ResearchGate
Eli Jerby at Google Scholar
1957 births
Living people
Academic staff of Tel Aviv University
Israeli scientists
Tel Aviv University alumni | Eli Jerby | [
"Materials_science"
] | 799 | [
"Metamaterials scientists",
"Metamaterials"
] |
76,492,287 | https://en.wikipedia.org/wiki/Gerald%20Koch | Gerald Koch (born in 1968) is a German wood scientist and professor, senior researcher and research scientific director at the Thünen-Institute of Wood Research at Hamburg, who is an elected fellow of the International Academy of Wood Science.
Research career
Koch obtained his PhD degree in wood science from the University of Hamburg in 1998.
Since 2004, he is the curator of the scientific wood collection, and also the head of wood anatomy at the Institute of Wood Research in Hamburg.
His research interests include topics of wood sciences related to macroscopic and microscopic wood identification of internationally traded timbers, forensic timber identification, investigation of wood structure, properties and utilisation of lesser known species, and also, topochemical analyses of wooden tissues on a subcellular level.
In the area of wood anatomy, he has been the initiator of the mobile apps, CITESwoodID and macroHOLZdata, which are commonly used by educational personnel, and professionals in wood industry and trade for the identification of tropical and non-tropical timbers.
Recognition
In 2008, he was elected as a fellow at the International Academy of Wood Science for his scientific work.
He is a member of the International Association of Wood Anatomists. In addition, Koch is an appointed advisor of the German Federal Ministry for the Environment, Nature Conservation, Nuclear Safety and Consumer Protection (BMUV), specifically on matters of subtropical and tropical timbers including certification and CITES regulations.
Koch presently serves as a member in the editorial boards of estemeed wood-related journals Holzforschung and European Journal of Wood and Wood Products.
Until April 2024, Koch has published and presented more than 200 research works in several referred journals, conferences and symposia, and possesses more than 4,000 citations at Google Scholar.
References
External links
Published work
Google Scholar
Wood biology, by Koch et al.
German scientists
Fellows of the International Academy of Wood Science
Wood scientists
1968 births
Living people
University of Hamburg alumni | Gerald Koch | [
"Materials_science"
] | 394 | [
"Wood sciences",
"Wood scientists"
] |
76,492,308 | https://en.wikipedia.org/wiki/History%20of%20radiation%20protection | The history of radiation protection begins at the turn of the 19th and 20th centuries with the realization that ionizing radiation from natural and artificial sources can have harmful effects on living organisms. As a result, the study of radiation damage also became a part of this history.
While radioactive materials and X-rays were once handled carelessly, increasing awareness of the dangers of radiation in the 20th century led to the implementation of various preventive measures worldwide, resulting in the establishment of radiation protection regulations. Although radiologists were the first victims, they also played a crucial role in advancing radiological progress and their sacrifices will always be remembered. Radiation damage caused many people to suffer amputations or die of cancer. The use of radioactive substances in everyday life was once fashionable, but over time, the health effects became known. Investigations into the causes of these effects have led to increased awareness of protective measures. The dropping of atomic bombs during World War II brought about a drastic change in attitudes towards radiation. The effects of natural cosmic radiation, radioactive substances such as radon and radium found in the environment, and the potential health hazards of non-ionizing radiation are well-recognized. Protective measures have been developed and implemented worldwide, monitoring devices have been created, and radiation protection laws and regulations have been enacted.
In the 21st century, regulations are becoming even stricter. The permissible limits for ionizing radiation intensity are consistently being revised downward. The concept of radiation protection now includes regulations for the handling of non-ionizing radiation.
In the Federal Republic of Germany, radiation protection regulations are developed and issued by the Federal Ministry for the Environment, Nature Conservation, Nuclear Safety and Consumer Protection (BMUV). The Federal Office for Radiation Protection is involved in the technical work. In Switzerland, the Radiation Protection Division of the Federal Office of Public Health is responsible, and in Austria, the Ministry of Climate Action and Energy.
X-rays
Early radiation consequences
The discovery of X-rays by Wilhelm Conrad Röntgen (1845-1923) in 1895 led to extensive experimentation by scientists, physicians, and inventors. The first X-ray machines produced extremely unfavorable radiation spectra for imaging with extremely high skin doses. In February 1896, John Daniel and William Lofland Dudley (1859–1914) of Vanderbilt University conducted an experiment in which Dudley's head was X-rayed, resulting in hair loss. Herbert D. Hawks, a graduate of Columbia University, suffered severe burns on his hands and chest during demonstration experiments with X-rays. Burns and hair loss were reported in scientific journals. Nikola Tesla (1856–1943) was one of the first researchers to explicitly warn of the potential dangers of X-rays in the Electrical Review on May 5, 1897 - after initially claiming them to be completely harmless. He suffered massive radiation damage after his experiments. Nevertheless, some doctors at the time still claimed that X-rays had no effect on humans. Until the 1940s, X-ray machines were operated without any protective safeguards.
Röntgen himself was spared the fate of the other X-ray users by habit. He always carried the unexposed photographic plates in his pockets and found that they were exposed if he remained in the same room during the exposure. So he regularly left the room when he took X-rays.
The use of X-rays for diagnostic purposes in dentistry was made possible by the pioneering work of C. Edmund Kells (1856-1928), a New Orleans dentist who demonstrated them to dentists in Asheville, North Carolina, in July 1896. Kells committed suicide after suffering from radiation-induced cancer for many years. He had been amputated one finger at a time, later his entire hand, followed by his forearm and then his entire arm.
Otto Walkhoff (1860-1934), one of the most important German dentists in history, took X-rays of himself in 1896 and is considered a pioneer in dental radiology. He described the required exposure time of 25 minutes as an "ordeal". Braunschweig's medical community later commissioned him to set up and supervise a central X-ray facility. In 1898, the year radium was discovered, he also tested the use of radium in medicine in a self-experiment using an amount of 0.2 grams of radium bromide. Walkhoff observed that cancerous mice exposed to radium radiation died significantly later than a control group of untreated mice. He thus initiated the development of radiation research for the treatment of tumors.
The Armenian-American radiologist Mihran Krikor Kassabian (1870-1910), vice president of the American Roentgen Ray Society (ARRS), was concerned about the irritating effects of X-rays. In a publication, he mentioned his increasing problems with his hands. Although Kassabian recognized X-rays as the cause, he avoided making this reference so as not to hinder the progress of radiology. In 1902, he suffered a severe radiation burn on his hand. Six years later, the hand became necrotic and two fingers of his left hand were amputated. Kassabian kept a diary and photographed his hands as the tissue damage progressed. He died of cancer in 1910.
Many of the early X-ray and radioactivity researchers went down in history as "martyrs for science." In her article, The Miracle and the Martyrs, Sarah Zobel of the University of Vermont tells of a 1920 banquet held to honor many of the pioneers of X-rays. Chicken was served for dinner: "Shortly after the meal was served, it could be seen that some of the participants were unable to enjoy the meal. After years of working with X-rays, many of the participants had lost fingers or hands due to radiation exposure and were unable to cut the meat themselves". The first American to die from radiation exposure was Clarence Madison Dally (1845-1904), an assistant to Thomas Alva Edison (1847-1931). Edison began studying X-rays almost immediately after Röntgen's discovery and delegated the task to Dally. Over time, Dally underwent more than 100 skin operations due to radiation damage. Eventually, both of his arms had to be amputated. His death led Edison to abandon all further X-ray research in 1904.
One of the pioneers was the Austrian Gustav Kaiser (1871-1954), who in 1896 succeeded in photographing a double toe with an exposure time of 1½-2 hours. Due to the limited knowledge at the time, he also suffered severe radiation damage to his hands, losing several fingers and his right metacarpal. His work was the basis for, among other things, the construction of lead rubber aprons. Heinrich Albers-Schönberg (1865-1921), the world's first professor of radiology, recommended gonadal protection for testicles and ovaries in 1903. He was one of the first to protect germ cells not only from acute radiation damage but also from small doses of radiation that could accumulate over time and cause late damage. Albers-Schönberg died at the age of 56 from radiation damage, as did Guido Holzknecht and Elizabeth Fleischman.
Since April 4, 1936, a radiology memorial in the garden of the of Hamburg's St. Georg Hospital has commemorated the 359 victims from 23 countries who were among the first medical users of X-rays.
Initial warnings
In 1896, the engineer Wolfram Fuchs, based on his experience with numerous X-ray examinations, recommended keeping the exposure time as short as possible, staying away from the tube, and covering the skin with Vaseline. In 1897, Chicago doctors William Fuchs and Otto Schmidt became the first users to have to pay compensation to a patient for radiation damage.
In 1901, dentist William Herbert Rollins (1852-1929) called for using lead-glass goggles when working with X-rays, for the X-ray tube to be encased in lead, and for all areas of the body to be covered with lead aprons. He published over 200 articles on the potential dangers of X-rays, but his suggestions were long ignored. A year later, Rollins wrote in despair that his warnings about the dangers of X-rays were not being heeded by either the industry or his colleagues. By this time, Rollins had demonstrated that X-rays could kill laboratory animals and induce miscarriages in guinea pigs. Rollins' achievements were not recognized until later. Since then, he has gone down in the history of radiology as the "father of radiation protection. He became a member of the Radiological Society of North America and its first treasurer.
Radiation protection continued to develop with the invention of new measuring devices such as the chromoradiometer by Guido Holzknecht (1872-1931) in 1902, the radiometer by Raymond Sabouraud (1864-1938) and Henri Noiré (1878–1937) in 1904/05, and the quantimeter by Robert Kienböck (1873-1951) in 1905, which made it possible to determine maximum doses at which there was a high probability that no skin changes would occur. Radium was also included by the British Roentgen Society, which published its first memorandum on radium protection in 1921.
Unnecessary applications
Pedoscope
Since the 1920s, pedoscopes have been installed in many shoe stores in North America and Europe, more than 10,000 in the U.S. alone, following the invention of Jacob Lowe, a Boston physicist. They were X-ray machines used to check the fit of shoes and to promote sales, especially to children. Children were particularly fascinated by the sight of their footbones. X-rays were often taken several times daily to evaluate the fit of different shoes. Most were available in shoe stores until the early 1970s. The energy dose absorbed by the customer was up to 116 rads, or 1.16 grays. In the 1950s, when medical knowledge of the health risks was already available, pedoscopes came with warnings that shoe-buyers should not be scanned more than three times a day and twelve times a year.
By the early 1950s, several professional organizations issued warnings against the continued use of shoe-mounted fluoroscopes, including the American Conference of Governmental Industrial Hygienists, the American College of Surgeons, the New York Academy of Medicine, and the American College of Radiology. At the same time, the District of Columbia enacted regulations requiring that shoe-mounted fluoroscopes be operated only by a licensed physical therapist. A few years later, the state of Massachusetts passed regulations stating that these machines could only be operated by a licensed physician. In 1957, the use of shoe-mounted fluoroscopes was banned by court order in Pennsylvania. By 1960, these measures and pressure from insurance companies led to the disappearance of the shoe-mounted fluoroscope, at least in the United States.
In Switzerland, there were 1,500 shoe-mounted fluoroscopes in use, 850 were required to be inspected by the Swiss Electrotechnical Association by a decree of the Federal Department of Home Affairs on October 7, 1963. The last one was decommissioned in 1990.
In Germany, the machines were not banned until 1976. The fluoroscopy machine emitted uncontrolled X-rays, which continuously exposed children, parents, and sales staff. The all-wood cabinet of the machine did not prevent the X-rays from passing through, resulting in particularly high cumulative radiation levels for the cashier when the pedoscope was placed near the cash register. The all-wood cabinet of the machine did not prevent the X-rays from passing through, resulting in particularly high cumulative radiation levels for the cashier when the pedoscope was placed near the cash register. It is clear that the machine was not designed with proper safety measures in place, leading to dangerous levels of radiation exposure. The well-established long-term effects of X-rays, including genetic damage and carcinogenicity, suggest that the use of pedoscopes worldwide over several decades may have contributed to health effects.The well-established long-term effects of X-rays, including genetic damage and carcinogenicity, suggest that the use of pedoscopes worldwide over several decades may have contributed to health effects. However, it cannot be definitively proven that they were the sole cause. For example, a direct link has been discussed in the case of basal cell carcinoma of the foot. In 1950, a case was published in which a shoe model had to have a leg amputated as a result.
Radiotherapy
In 1896, Viennese dermatologist Leopold Freund (1868-1943) used X-rays to treat patients for the first time. He successfully irradiated the hairy nevus of a young girl. In 1897, Hermann Gocht (1869–1931) published the treatment of trigeminal neuralgia with X-rays, and Alexei Petrovich Sokolov (1854-1928) wrote about radiotherapy for arthritis in the oldest radiology journal, Advances in the field of X-rays (RöFo). In 1922, X-rays were recommended as safe for many diseases and for diagnostic purposes. Radiation protection was limited to recommending doses that would not cause erythema (reddening of the skin). For example, X-rays were promoted as an alternative to tonsillectomy. It was also boasted that in 80% of cases of diphtheria carriers, Corynebacterium diphtheriae was no longer detectable within two to four days. In the 1930s, Günther von Pannewitz (1900–1966), a radiologist from Freiburg, Germany, perfected what he called X-ray stimulation radiation for degenerative diseases. Low-dose radiation reduces the inflammatory response of tissues. Until about 1960, children with diseases such as ankylosing spondylitis or favus (head fungus) were irradiated, which was effective but led to increased cancer rates among patients decades later. In 1926, the American pathologist James Ewing (1866-1943) was the first to observe bone changes as a result of radiotherapy, which he described as radiation osteitis (now Osteoradionecrosis). In 1983, Robert E. Marx stated that osteoradionecrosis is radiation-induced aseptic bone necrosis. The acute and chronic inflammatory processes of osteoradionecrosis are prevented by the administration of steroidal anti-inflammatory drugs. In addition, the administration of pentoxifylline and antioxidant treatments, such as superoxide dismutase and tocopherol (vitamin E) are recommended.
Radiation protection during X-ray examinations
Preliminary observation
Sonography (ultrasound diagnostics) is a versatile and widely used imaging modality in medical diagnostics. Ultrasound is also used in therapy. However, it uses mechanical waves and no ionizing or non-ionizing radiation. Patient safety is ensured if the recommended limits for avoiding cavitation and overheating are observed, see also Safety Aspects of Sonography.
Even devices that use alternating magnetic fields in the radiofrequency range, such as magnetic resonance imaging (MRI), do not use ionizing radiation. MRI was developed as an imaging technique in 1973 by Paul Christian Lauterbur (1929-2007) with significant contributions from Sir Peter Mansfield (1933-2017). Jewelry or piercings can become very hot; on the other hand, a high tensile force is exerted on the jewelry, which in the worst case can cause it to be torn out. To avoid pain and injury, jewelry containing ferromagnetic metals should be removed beforehand. Pacemakers, defibrillator systems, and large tattoos in the examination area that contain metallic color pigments may heat up or cause second-degree burns or malfunction of the implants.
Photoacoustic Tomography (PAT) is a hybrid imaging modality that utilizes the photoacoustic effect without the use of ionizing radiation. It works without contact with very fast laser pulses that generate ultrasound in the tissue under examination. The local absorption of the light leads to sudden local heating and the resulting thermal expansion. The result is broadband acoustic waves. The original distribution of absorbed energy can be reconstructed by measuring the outgoing ultrasound waves with appropriate ultrasound transducers.
Radiation exposure detection
In order to better assess radiation protection, the number of X-ray examinations, including the dose, has been recorded annually in Germany since 2007. However, the Federal Statistical Office does not have complete data for conventional X-ray examinations. In 2014, the total number of X-ray examinations in Germany was estimated to be about 135 million, of which about 55 million were dental X-ray examinations. The average effective dose from x-ray examinations per inhabitant in Germany in 2014 was about 1.55 mSv (about 1.7 x-ray examinations per inhabitant per year). The proportion of dental X-rays is 41%, but accounts for only 0.4% of the collective effective dose.
In Germany, Section 28 of the X-ray Ordinance (RöV) has required since 2002 that the attending physician must have an X-ray pass available for X-ray examinations and offer it to the patient. The pass contains information about the patient's X-rays to avoid unnecessary examinations and to allow comparison with previous images. With the entry into force of the new Radiation Protection Ordinance on December 31, 2018, this obligation no longer applies. In Austria and Switzerland, x-ray passports have so far been available voluntarily. In principle, there must always be both a justifiable indication for the use of X-rays and the informed consent of the patient. In the context of medical treatment, informed consent refers to the patient's agreement to all types of interventions and other medical measures.
Radiation reduction
Over the years, there have been increasing efforts to reduce radiation exposure to therapists and patients.
Radiation protective clothing
Following Rollins' discovery in 1920 that lead aprons protected against X-rays, lead aprons with a lead thickness of 0.5 mm were introduced. Due to their weight, lead-free and lead-reduced aprons were subsequently developed. In 2005, it was recognized that in some cases the protection was significantly less than wearing lead aprons. The lead-free aprons contain tin, antimony and barium, which have the property of producing intense radiation (X-ray fluorescence radiation) when irradiated. In Germany, the Radiology Standards Committee has taken up the issue and introduced a German standard (DIN 6857-1) in 2009. The international standard IEC 61331-3:2014 was finally published in 2014. Protective aprons that do not comply with DIN 6857-1 of 2009 or the new IEC 61331-1 of 2014 may result in higher exposures. There are two classes of lead equivalency classes: 0.25 mm and 0.35 mm. The manufacturer must specify the area weight in kg/m2 at which the protective effect of a pure lead apron of 0.25 or 0.35 mm Pb is achieved. The protective effect of an apron shall be appropriate to the energy range used, up to 110 kV for low energy aprons and up to 150 kV for high energy aprons.
If necessary, lead glass panels must also be used, with the front panels having a lead equivalent of 0.5-1.0 mm, depending on the application, and the side shields having a lead equivalent of 0.5-0.75 mm.
Outside the useful beam, radiation exposure is primarily caused by scattered radiation from the tissue being scanned. During examinations of the head and torso, this scattered radiation can spread throughout the body and is difficult to shield with radiation protective clothing. Fears that a lead apron will prevent radiation from leaving the body are unfounded, however, because lead absorbs radiation rather than scattering it.
When preparing an orthopantomogram (OPG) for a dental overview radiograph, it is sometimes recommended not to wear a lead apron, as it does little to shield scattered radiation from the jaw area, but may hinder the rotation of the imaging device. However, according to the 2018 X-ray regulation, it is still mandatory to wear a lead apron when taking an OPG.
X-ray intensifier foils
In the same year as the discovery of X-rays, Mihajlo Idvorski Pupin (1858-1935) invented the method of placing a sheet of paper coated with fluorescent substances on the photographic plate, drastically reducing the exposure time and thus the radiation exposure. 95% of the film was blackened by the intensifying film and only the remaining 5% was directly blackened by the X-rays. Thomas Alva Edison identified the blue-emitting calcium tungstate (CaWO4) as a suitable phosphor, which quickly became the standard for X-ray intensifying film. In the 1970s, calcium tungstate was replaced by even better and finer intensifying films with rare earth-based phosphors (terbium-activated lanthanum oxybromide, gadolinium oxysulfide). The use of intensifying films in dental film production did not become widespread because of the loss of image quality. The combination with high-sensitivity films further reduced radiation exposure.
Anti-scatter grid
An anti-scatter grid is a device in X-ray technology that is placed in front of the image receiver (screen, detector, or film) and reduces the incidence of diffuse radiation on it. The first diffusion radiation grid was developed in 1913 by Gustav Peter Bucky (1880-1963). The US radiologist Hollis Elmer Potter (1880-1964) improved it in 1917 by adding a moving device. The radiation dose must be increased when using scattered radiation grids. For this reason, the use of scattered radiation equipment should not be used on children. In digital radiography, a grid may be omitted under certain conditions to reduce radiation exposure to the patient.
Radiation protection splint
Radiation protection measures may also be necessary against scattered radiation, which occurs during tumor irradiation of the head and neck on metal parts of the dentition (dental fillings, bridges, etc.). Since the 1990s, soft tissue retractors known as radiation protection splints have been used to prevent or reduce mucositis, an inflammation of the mucous membranes. It is the most significant adverse acute side effect of radiation. The radiation protection splint is a spacer that keeps the mucosa away from the teeth and reduces the amount of scattered radiation that hits the mucosa according to the square law of distance. Mucositis, which is extremely painful, is one of the most significant detriments to a patient's quality of life and often limits radiation therapy, thereby reducing the chances of tumor cure. The splint reduces oral mucosal reactions that typically occur in the second and third third of a radiation series and are irreversible.
Panoramic X-ray machine
The Japanese Hisatugu Numata developed the first panoramic radiograph in 1933/34. This was followed by the development of intraoral panoramic X-ray units, in which the X-ray tube is placed intraorally (inside the mouth) and the X-ray film extraorally (outside the mouth). At the same time, Horst Beger from Dresden in 1943 and the Swiss dentist Walter Ott in 1946 worked on the Panoramix (Koch & Sterzel), Status X (Siemens) and Oralix (Philips). Intraoral panoramic devices were discontinued at the end of the 1980s because the radiation exposure was too high in direct contact with the tongue and oral mucosa due to the intraoral tube.
Digital X-ray
Eastman Kodak filed the first patent for digital radiography in 1973. The first commercial CR (Computed Radiology) solution was offered by Fujifilm in Japan in 1983 under the device name CR-101. X-ray imaging plates are used in X-ray diagnostics to record the shadow image of X-rays. The first commercial digital X-ray system for use in dentistry was introduced in 1986 by Trophy Radiology (France) under the name Radiovisiography. Digital x-ray systems help reduce radiation exposure. Instead of film, the machines contain a scintillator that converts the incident X-ray photons either into visible light or directly into electrical impulses.
Computer tomography
In 1972, the first commercial CT scanner for clinical use went into operation at Atkinsons Morley Hospital in London. Its inventor was the English engineer Godfrey Newbold Hounsfield (1919-2004), who shared the 1979 Nobel Prize in Medicine with Allan McLeod Cormack (1924-1998) for his pioneering work in the field of computed tomography. The first steps toward dose reduction were taken in 1989 in the era of single-slice spiral CT. The introduction of multi-slice spiral computed tomography in 1998 and its continuous development made it possible to reduce the dose by means of dose modulation. The tube current is adjusted, for example by reducing the power for images of the lungs compared to the abdomen. The tube current is modulated during rotation. Because the human body has an approximately oval cross-section, radiation intensity is reduced when radiation is delivered from the front or back, and is increased when radiation is delivered from the side. This dose control also depends on the body mass index. For example, the use of dose modulation in the head and neck region reduces total exposure and organ doses to the thyroid and eye lens by up to 50% without significantly compromising diagnostic image quality. The Computed Tomography Dose Index (CTDI) is used to measure radiation exposure during a CT scan. The CTDI was first defined by the Food and Drug Administration (FDA) in 1981. The unit of measurement for the CTDI is the mGy (milli-Gray). Multiplying the CTDI by the length of the examination volume yields the dose-length product (DLP), which quantifies the total radiation exposure to the patient during a CT scan.
Structural protective measures
An X-ray room must be shielded on all sides with 1 mm lead equivalent shielding. Calcium silicate or solid brick masonry is recommended. A steel jamb should be used, not only because of the weight of the heavy shielding door but also because of the shielding; wooden frames must be shielded separately. The shielding door must be covered with a 1 mm thick lead foil and a lead glass window must be installed as a visual connection. A keyhole shall be avoided. All installations (sanitary or electrical), that interrupt the radiation protection, must be leaded (
and
Depending on the application, nuclear medicine requires even more extensive protective measures, up to and including concrete walls several meters thick. In addition, from December 31, 2018, when the latest amendments to Section 14 (1) No. 2b of the Radiation Protection Act
come into force, an expert in medical physics for X-ray diagnostics and therapy must be consulted for the optimization and quality assurance of the application and for advice on radiation protection issues.
Certificate of competence
Each facility operating an x-ray unit shall have sufficient personnel with appropriate expertise. The person responsible for radiation protection or one or more Radiation Safety Officers shall have appropriate qualifications, which shall be regularly updated. X-ray examinations may be technically performed by any other staff member of a medical or dental practice if they are under the direct supervision and responsibility of the person responsible and if they have knowledge of radiation protection.
This knowledge of radiation protection has been required since the amendment of the X-ray Ordinance in 1987; medical and dental assistants (then called medical assistants or dental assistants) received this additional training in 1990. The regulations for the specialty of radiology were tightened by the Radiation Protection Act, which came into force on October 1, 2017.
The handling of radioactive substances and ionizing radiation (if not covered by the X-ray Ordinance) is regulated by the Radiation Protection Ordinance (StrlSchV). Section 30 StrlSchV
defines the "Required expertise and knowledge in radiation protection".
Radiation protection associations
The Association of German Radiation Protection Physicians (VDSÄ) was formed in the late 1950s from a working group of radiation protection physicians of the German Red Cross and was founded in 1964. It was dedicated to the promotion of radiation protection and the representation of medical, dental, and veterinary radiation protection concerns to the public and the health care system. In 2017, it was merged into the Professional Association for Radiation Protection. The Austrian Association for Radiation Protection (ÖVS), founded in 1966, pursues the same goals as the Association for Medical Radiation Protection in Austria. The Professional Association for Radiation Protection for Germany and Switzerland is networked worldwide.
Radiation protection in radiotherapy
In radiotherapy, radiation protection is often overlooked in favor of structural safeguards and therapist protection. The benefit/risk assessment should prioritize both the therapeutic goal of treating the patient's cancer and the safety of all involved. However, it is crucial to ensure that radiation is delivered only where it is needed through appropriate treatment planning. By employing strong radiation protection measures, we can confidently provide effective treatment while minimizing potential risks. Linear accelerators replaced cobalt and caesium emitters in routine therapy due to their superior technical characteristics and risk profile. They have been available since about 1970. The presence of a medical physicist responsible for technical quality control is required for linear accelerators, unlike X-rays and telecurie systems. It is important to note that radiation necrosis is the necrosis of cells in an organism caused by the effects of ionizing radiation. Radionecrosis is a serious complication of radiosurgical treatment that becomes clinically apparent months or years after irradiation. Radiation therapy has significantly reduced the incidence of radionecrosis since its early days. Modern radiation techniques prioritize the sparing of healthy tissue while irradiating as much of the area around the tumor as possible to prevent recurrence. It is important to note that patients undergoing radiotherapy face a certain level of radiation risk.
Radiation protection and radiation damage in veterinary medicine
While there is limited literature on radiation injury to animals, there is no evidence of other types of radiation injury. Diagnostic radiation has been shown to cause local burns in animals, typically resulting from prolonged exposure of body parts or sparks from old x-ray tubes. It is important to note that the frequency of injury to veterinary staff and veterinarians is significantly lower than that in human medicine, highlighting the safety of diagnostic radiation in veterinary practice. In veterinary medicine, fewer images are taken compared to human medicine, particularly fewer CT scans. However, due to the manual restraint of animals to avoid anesthesia, at least one person is present in the control area, resulting in significantly higher radiation exposure than that of human medical staff. It is important to note that since the 1970s, dosimeters have been used to measure the radiation exposure of veterinary personnel, ensuring their safety.
Feline hyperthyroidism (overactive thyroid) is a common disease in older cats. Radioiodine therapy is considered by many authors to be the treatment of choice. Following the administration of radioactive iodine, cats are kept in an isolation pen. The cat's radioactivity is measured to determine the time of discharge, which is typically 14 days after the start of therapy. The therapy requires significant radiation protection measures and is currently only offered at two veterinary facilities in Germany (as of 2010). After the start of treatment, cats must be kept indoors for four weeks, and contact with pregnant women and children under the age of 16 must be avoided due to residual radioactivity.
Just like a medical practice, any veterinary practice operating an X-ray machine must have sufficient staff with the appropriate expertise, as required by Section 18 of the X-Ray Ordinance 2002. The corresponding training for paraveterinary workers (then called veterinary nurses) took place in 1990.
In 2017, Linsengericht (Hesse) opened Europe's first clinic for horses with cancer. Radiation therapy is administered in a treatment room that is eight meters wide, on a specially designed table that can withstand heavyweight. The surrounding area is protected from radiation by three-meter thick walls. Mobile equipment is used to irradiate tumors in small animals at various locations.
Radioactive substances
Radon
Radon is a naturally occurring radioactive noble gas discovered in 1900 by Friedrich Ernst Dorn (1848-1916) and is considered carcinogenic. Radon is increasingly found in areas with high levels of uranium and thorium in the soil. These are mainly areas with high granitic rock deposits. According to studies by the World Health Organization, the incidence of lung cancer increases significantly at radiation levels of 100-200 Bq per cubic meter of indoor air. The likelihood of developing lung cancer increases by 10% with each additional 100 Bq/m3 of indoor air.
Elevated radon levels have been measured in numerous areas in Germany, particularly in southern Germany, Austria and Switzerland.
Germany
The Federal Office for Radiation Protection has developed a radon map of Germany. The EU Directive 2013/59/Euratom (Radiation Protection Basic Standards Directive) introduced reference levels and the possibility for workers to have their workplace tested for radon exposure. In Germany, it was implemented in the Radiation Protection Act (Chapter 2 or Sections 124-132 StrlSchG)
and the amended Radiation Protection Ordinance (Part 4 Chapter 1, Sections 153-158 StrlSchV).
The new radon protection regulations for workplaces and new residential buildings have been binding since January 2019. Extensive radon contamination and radon precautionary areas have been determined by the ministries of the environment of the federal states (as of June 15, 2021).
Austria
The highest radon concentrations in Austria were measured in 1991 in the municipality of Umhausen in Tyrol. Umhausen has about 2300 inhabitants and is located in the Ötztal valley. Some of the houses there were built on a bedrock of granite gneiss. From this porous subsoil, the radon present in the rock seeped freely into the unsealed cellars, which were contaminated with up to 60,000 Becquerels of radon per cubic meter of air. Radon levels in the apartments in Umhausen have been systematically monitored since 1992. Since then, extensive radon mitigation measures have been implemented in the buildings: New buildings, sealing of cellar floors, forced ventilation of cellars or relocation. Queries in the Austrian Health Information System (ÖGIS) have shown that the incidence of new cases of lung cancer has declined sharply since then. The Austrian National Radon Project (ÖNRAP) has studied radon exposure throughout the country. Austria also has a Radiation Protection Act as a legal basis. Indoor limits were set in 2008 The Austrian Ministry of the Environment states that
In Austria, the Radon Protection Ordinance in its version of September 10, 2021 is currently in force, which also defines the radon protection areas and radon precautionary areas.
Switzerland
The aim of the Radon Action Plan 2012-2020 in Switzerland was to incorporate the new international recommendations into the Swiss strategy for protection against radon and thus reduce the number of lung cancer cases attributable to radon in buildings.
On 1 January 2018, the limit value of 1000 Bq/m3 was replaced by a reference value of 300 becquerels per cubic meter (Bq/m3) for the radon gas concentration averaged over a year in "rooms in which people regularly spend several hours a day".
Subsequently, on May 11, 2020, the Federal Office of Public Health FOPH issued the Radon Action Plan 2021-2030. The provisions on radon protection are primarily laid down in the Radiation Protection Ordinance (RPO).
Radiation sickness among miners
In 1879, Walther Hesse (1846-1911) and Friedrich Hugo Härting published the study "Lung Cancer, the Miners' Disease in the Schneeberg Mines". Hesse, a pathologist, was shocked by the poor health and young age of the miners. This particular form of bronchial carcinoma was given the name Schneeberg disease because it occurred among miners in the Schneeberg mines (Saxon Erz Mountains).
When Hesse's report was published, radioactive radiation and the existence of radon were unknown. It was not until 1898 that Marie Curie-Skłodowska (1867-1934) and her husband Pierre Curie (1859-1906) discovered radium and created the concept of radioactivity. Beginning in the fall of 1898, Marie Curie suffered from inflammation of the fingertips, the first known symptoms of radiation sickness.
In the Jáchymov mines, where silver and non-ferrous metals were mined from the 16th to the 19th century, uranium ore was mined in abundance in the 20th century. It was only during the Second World War that restrictions were imposed on ore mining in the Schneeberg and Jáchymov mines. After World War II, uranium mining was accelerated for the Soviet atomic bomb project and the emerging Soviet nuclear industry. Forced labor was used. Initially, these were German prisoners of war and displaced persons, and after the February Revolution of 1948, political prisoners were imprisoned by the Communist Party regime in Czechoslovakia, as well as conscripted civilian workers. Several "Czechoslovak gulags" were established in the area to house these workers. In all, about 100,000 political prisoners and more than 250,000 forced laborers passed through the camps. About half of them probably did not survive the mining work. Uranium mining ceased in 1964. We can only speculate about other victims who died as a result of radiation. Radon-bearing springs discovered during the mining in the early 20th century established a spa industry that is still important today, as well as the town's status as the oldest radium brine spa in the world.
Wismut AG
The approximately 200,000 uranium miners employed by Wismut AG in the former Soviet occupation zone of East Germany were exposed to very high levels of radiation, particularly between 1946 and 1955, but also in later years. This exposure was caused by the inhalation of radon and its radioactive by-products, which were deposited to a considerable extent in the inhaled dust. Radiation exposure was expressed in the historical unit of working level month (WLM). This unit of measurement was introduced in the 1950s specifically for occupational safety in uranium mines in the U.S. to record radiation exposure resulting from radioactive exposure to radon and its decay products in the air we breathe. Approximately 9000 workers at Wismut AG have been diagnosed with lung cancer.
Radium
Until the 1930s, radium compounds were not only considered relatively harmless, but also beneficial to health, and were advertised as medicines for a variety of ailments or used in products that glowed in the dark. Processing took place without any safeguards.
Until the 1960s, radioactivity was often handled naively and carelessly. From 1940 to 1945, the Berlin-based Auergesellschaft, founded by Carl Auer von Welsbach (1858-1929, Osram), produced a radioactive toothpaste called Doramad that contained thorium-X and was sold internationally. It was advertised with the statement, "Its radioactive radiation strengthens the defenses of the teeth and gums. The cells are charged with new life energy and the destructive effect of bacteria is inhibited. This gave the claim of radiant white teeth a double meaning. By 1930, there were also bath additives and eczema ointments under the brand name "Thorium-X". Radium was also added to toothpastes, such as Kolynos toothpaste. After World War I, radioactivity became a symbol of modern achievement and was considered "chic". Radioactive substances were added to mineral water, condoms, and cosmetic powders. Even chocolate laced with radium was sold. The toy manufacturer Märklin in the Swabian town of Göppingen tested the sale of an X-ray machine for children. At upper-class parties, people "photographed" each other's bones for fun. A system called Trycho () for epilation (hair removal) of the face and body was franchised in the USA. As a result, thousands of women suffered skin burns, ulcers and tumors. It was not until the atomic bombings of Hiroshima and Nagasaki that the public became aware of the dangers of ionizing radiation and these products were banned.
A radium industry developed, using radium in creams, beverages, chocolates, toothpastes, and soaps. It took a relatively long time for radium and its decay product radon to be recognized as the cause of the observed effects. Radithor, a radioactive agent consisting of triple-distilled water in which the radium isotopes 226Ra and 228Ra were dissolved so that it had an activity of at least one microcurie, was marketed in the United States. It was not until 1932, when the prominent American athlete Eben Byers, who by his own account had taken about 1,400 vials of Radithor as medicine on the recommendation of his physician, fell seriously ill with cancer, lost many of his teeth, and died shortly thereafter in great agony, that strong doubts were raised about the healing powers of Radithor and radium water.
Radium cures
1908 saw a boom in the use of radioactive water for therapeutic purposes. The discovery of springs in Oberschlema and Bad Brambach paved the way for the establishment of radium spas, which relied on the healing properties of radium. During the cures, people bathed in radium water, drank cures with radium water, and inhaled radon in emanatoriums. The baths were visited by tens of thousands of people every year, hoping for hormesis.
To this day, therapeutic applications are carried out in spas and healing tunnels. The natural release of radon from the ground is used. According to the German Spa Association, the activity in water must be at least 666 Bq/liter. The requirement for inhalation treatments is at least 37,000 Bq/m3 of air. This form of therapy is not scientifically accepted and the potential risk of radiation exposure is criticized. The equivalent dose of a radon cure in Germany is given by the individual health resorts as about one to two millisieverts, depending on the location. In 2010, doctors in Erlangen, using the (outdated) LNT (Linear, No-Threshold) model, concluded that five percent of all lung cancer deaths in Germany are caused by radon. There are radon baths in Bad Gastein, Bad Hofgastein and Bad Zell in Austria, in Niška Banja in Serbia, in the radon revitalization bath in Menzenschwand and in Bad Brambach, Bad Münster am Stein-Ebernburg, Bad Schlema, Bad Steben, Bad Schmiedeberg and Sibyllenbad in Germany, in Jáchymov in the Czech Republic, in Hévíz in Hungary, in Świeradów-Zdrój (Bad Flinsberg) in Poland, in Naretschen and Kostenez in Bulgaria and on the island of Ischia in Italy. There are radon tunnels in Bad Kreuznach and Bad Gastein.
Illuminated dials
The dangers of radium were recognized in the early 1920s and first described in 1924 by New York dentist and oral surgeon Theodor Blum (1883-1962). He was particularly aware of the use of radium in the watch industry, where it was used for luminous dials. He published an article on the clinical picture of the so-called radium jaw. He observed this disease in female patients who, as dial painters, came into contact with luminous paint whose composition was similar to Radiomir, a luminous material invented in 1914 consisting of a mixture of zinc sulfide and radium bromide. As they painted, they used their lips to form the tip of the phosphorus-laden brush into the desired pointed shape, and this is how the radioactive radium entered their bodies. In the U.S. and Canada alone, about 4,000 workers were affected over the years. In retrospect, the factory workers were called the Radium Girls. They also played with the paint, painting their fingernails, teeth and faces. This made them glow at night to the surprise of their companions.
After Harrison Stanford Martland (1883-1954), chief medical examiner in Essex County, detected the radioactive noble gas radon (a decay product of radium) in the breath of the Radium Girls, he turned to Charles Norris (1867-1935) and Alexander Oscar Gettler (1883-1968). In 1928, Gettler was able to detect a high concentration of radium in the bones of Amelia Maggia, one of the young women, even five years after her death. In 1931, a method was developed for determining radium dosage using a film dosimeter. A standard preparation is irradiated through a hardwood cube onto an X-ray film, which is then blackened. For a long time, the cube minute was an important unit of radium dosage. It was calibrated by ionometric measurements. The radiologists Hermann Georg Holthusen (1886-1971) and Anna Hamann (1894-1969) found a calibration value of 0.045 r/min in 1932/1935. The calibration film receives the y-ray dose of 0.045 r per minute through the wooden cube from the preparation of 13.33 mg. In 1933, the physicist Robley D. Evans (1907-1995) made the first measurements of radon and radium in the excretions of female workers. On this basis, the National Bureau of Standards, the predecessor to the National Institute of Standards and Technology (NIST), set the limit for radium at 0.1 microcuries (about 3.7 kilobecquerels) in 1941.
A Radium Action Plan 2015-2019 aims to solve the problem of radiological contamination in Switzerland, mainly in the Jura Mountains, due to the use of radium luminous paint in the watch industry until the 1960s.
In France, a line of cosmetics called Tho-Radia, which contained both thorium and radium, was created in 1932 and lasted until the 1960s.
Other terrestrial radiation
Terrestrial radiation is the ubiquitous radiation on Earth caused by radionuclides in the ground that were formed billions of years ago by stellar nucleosynthesis and have not yet decayed due to their long half-lives. Terrestrial radiation is caused by natural radionuclides that occur naturally in the Earth's soil, rocks, hydrosphere, and atmosphere. Natural radionuclides can be divided into cosmogenic and primordial nuclides. Cosmogenic nuclides do not contribute significantly to the terrestrial ambient radiation at the Earth's surface. The sources of terrestrial radiation are the natural radioactive nuclides found in the uppermost layers of the Earth, in the water and in the air. These include in particular
Thorium-232 (half-life 14 billion years),
Uranium-238 (half-life 4.4 billion years),
Uranium-235 (half-life 0.7 billion years) and
Potassium-40 (half-life 1.3 billion years).
Mining and extraction of fuels
According to the World Nuclear Association, coal from all deposits contains traces of various radioactive substances, particularly radon, uranium and thorium. These substances are released during coal mining, especially from surface mines, through power plant emissions, or power plant ash, and contribute to terrestrial radiation exposure through their exposure pathways.
In December 2009, it was revealed that oil and gas production generates millions of tons of radioactive waste each year, much of which is improperly disposed of without detection, including 226Radium and 210Polonium. The specific activity of the waste ranges from 0.1 to 15,000 becquerels per gram. In Germany, according to the Radiation Protection Ordinance of 2001, the material is subject to monitoring at one Becquerel per gram and would have to be disposed of separately. The implementation of this regulation has been left to the industry, which has disposed of the waste carelessly and improperly for decades.
Building material
Every building material contains traces of natural radioactive substances, especially 238uranium, 232thorium, and their decay products, and 40potassium. Solidified and effusive rocks such as granite, tuff, and pumice have higher levels of radioactivity. In contrast, sand, gravel, limestone, and natural gypsum (calcium sulfate dihydrate) have low levels of radioactivity. The European Union's Activity Concentration Index (ACI), developed in 1999, can be used to assess radiation exposure from building materials. It replaces the Leningrad summation formula, which was used in 1971 in Leningrad (St. Petersburg) to determine how much radiation exposure from building materials is permissible for humans. The ACI is calculated from the sum of the weighted activities of 40potassium, 226radium, and 232thorium. The weighting takes into account the relative harmfulness to humans. According to official recommendations, building materials with a European ACI value greater than "1" should not be used in large quantities.
Glazes
Uranium pigments are used to color ceramic tiles with uranium glazes (red, yellow, brown), where 2 mg of uranium per cm2 is allowed. Between 1900 and 1943, large quantities of uranium-containing ceramics were produced in the United States, as well as in Germany and Austria. It is estimated that between 1924 and 1943, 50-150 tons of uranium (V,VI) oxide were used annually in the U.S. to produce uranium-containing glazes. In 1943, the U.S. government imposed a ban on the civilian use of uranium-containing substances, which remained in effect until 1958. Beginning in 1958, the U.S. government, and in 1969 the United States Atomic Energy Commission, sold depleted uranium in the form of uranium(VI) fluoride for civilian use. In Germany, uranium-glazed ceramics were produced by the Rosenthal porcelain factory and were commercially available until the early 1980s. Uranium-glazed ceramics should only be used as collector's items and not for everyday use due to possible abrasion.
ODL measurement network
The Federal Office for Radiation Protection's monitoring network measures natural radiation exposure through the local dose rate (ODL), expressed in microsieverts per hour (μSv/h). In Germany, the natural ODL ranges from approximately 0.05 to 0.18 μSv/h, depending on local conditions. The ODL monitoring network has been operational since 1973 and currently comprises 1800 fixed, automatically operating measuring points. Its primary function is to provide early warning for the rapid detection of increased radiation from radioactive substances in the air in Germany. Spectroscopic probes have been successfully utilized since 2008 to determine the contribution of artificial radionuclides in addition to the local dose rate, showcasing the network's advanced capabilities. In addition to the ODL monitoring network of the Federal Office for Radiation Protection, there are other federal monitoring networks at the Federal Maritime and Hydrographic Agency and the Federal Institute of Hydrology, which measure gamma radiation in water; the German Meteorological Service measures air activity with aerosol samplers. To monitor nuclear facilities, the relevant federal states operate their own ODL monitoring networks. The data from these monitoring networks are automatically fed into the Integrated Measurement and Information System (IMIS), where they are used to analyze the current situation.
Many countries operate their own ODL monitoring networks to protect the public. In Europe, these data are collected and published on the EURDEP platform of the European Atomic Energy Community. The European monitoring networks are based on Articles 35 and 37 of the Euratom Treaty.
Radionuclides in medicine
Nuclear medicine is the use of open radionuclides for diagnostic and therapeutic purposes (radionuclide therapy). It also includes the use of other radioactive substances and nuclear physics techniques for functional and localization diagnostics. George de Hevesy (1885-1966) lived as a lodger and in 1923 suspected that his landlady was offering him pudding that he had not eaten the following week. He mixed a small amount of a radioactive isotope into the leftovers. When she served him the pudding a week later, he was able to detect radioactivity in a sample of the casserole. When he showed this to his landlady, she immediately gave him notice. The method he used made him the father of nuclear medicine. It became known as the tracer method, which is still used today in nuclear medicine diagnostics. A small amount of a radioactive substance, its distribution in the organism, and its path through the human body can be tracked externally. This provides information about various metabolic functions of the body. The continuous development of radionuclides has improved radiation protection. For example, the mercury compounds 203chloro-merodrin and 197chloro-merodrin were abandoned in the 1960s as substances were developed that allowed a higher photon yield with less radiation exposure. Beta emitters such as 131I and 90Y are used in radionuclide therapy. In nuclear medicine diagnostics, the beta+ emitters 18F, 11C, 13N, and 15O are used as radioactive markers for tracers in positron emission tomography (PET). Radiopharmaceuticals (isotope-labeled drugs) are being developed on an ongoing basis.
Radiopharmaceutical residues, such as empty application syringes and contaminated residues from the patient's toilet, shower and washing water, are collected in tanks and stored until they can be safely pumped into the sewer system. The storage time depends on the half-life and ranges from a few weeks to a few months, depending on the radionuclide. Since 2001, by
of the Radiation Protection Ordinance, the specific radioactivity in the waste containers has been recorded in release measuring stations and the release time is calculated automatically. This requires measurements of the sample activity in Bq/g and the surface contamination in Bq/cm2. In addition, the behavior of the patients after their discharge from the clinic is prescribed. To protect personnel, syringe filling systems, borehole measurement stations for nuclide-specific measurement of low-activity, small volume individual samples, a lift system into the measurement chamber to reduce radiation exposure when handling highly active samples, probe measurement stations, ILP (isolated limb perfusion) measurement stations to monitor activity with one or more detectors during surgery and report leakage to the surgical oncologist.
Radioiodine therapy
Radioiodine Therapy (RIT) is a nuclear medicine procedure used to treat thyroid hyperfunction, Graves' disease, thyroid enlargement, and certain forms of thyroid cancer. The radioactive iodine isotope used is 131Iodine, a predominant beta emitter with a half-life of eight days, which is only stored in thyroid cells in the human body. In 1942, Saul Hertz (1905-1950) of the Massachusetts General Hospital and the physicist Arthur Roberts published their report on the first radioiodine therapy (1941) for Graves' disease, at that time still predominantly using the 130iodine isotope with a half-life of 12.4 hours. At the same time, Joseph Gilbert Hamilton (1907-1957) and John Hundale Lawrence (1904-1991) performed the first therapy with 131iodine, the isotope still used today.
Radioiodine therapy is subject to special legal regulations in many countries, and in Germany may only be performed on an inpatient basis. There are approximately 120 treatment centers in Germany (as of 2014), performing approximately 50,000 treatments per year. In Germany, the minimum length of stay is 48 hours. Discharge depends on the residual activity remaining in the body. In 1999, the limit for residual activity was raised. The dose rate may not exceed 3.5 μSv per hour at a distance of 2 meters from the patient, which means that a radiation exposure of 1 mSv may not be exceeded within one year at a distance of 2 meters. This corresponds to a residual activity of about 250 MBq. Similar regulations exist in Austria.
In Switzerland, a maximum radiation exposure of 1 mSv per year and a maximum of 5 mSv per year for the patient's relatives may not be exceeded. After discharge following radioiodine therapy, a maximum dose rate of 5 μSv per hour at a distance of 1 meter is permitted, which corresponds to a residual activity of approximately 150 MBq. In the event of early discharge, the supervisory authority must be notified up to a dose rate of 17.5 μSv/h; above 17.5 μSv/h, permission must be obtained. If the patient is transferred to another ward, the responsible radiation protection officer must ensure that appropriate radiation protection measures are taken there, e.g. that a temporary control area is set up.
Scintigraphy
Scintigraphy is a nuclear medicine procedure in which low-level radioactive substances are injected into the patient for diagnostic purposes. These include bone scintigraphy, thyroid scintigraphy, octreotide scintigraphy, and, as a further development of the procedure, single photon emission computed tomography (SPECT). For example, 201Tl thallium(I) chloride, technetium compounds (99mTc tracer, 99mtechnetium tetrofosmin), PET tracers (with radiation exposure of 1100 MBq each with 15O-water, 555 MBq with 13N ammonia, or 1850 MBq with 82Rb rubidium chloride) are used in myocardial scintigraphy to diagnose blood flow conditions and function of the heart muscle (myocardium). The examination with 74 MBq 201Thallium Chloride causes a radiation exposure of about 16 mSv (effective dose equivalent), the examination with 740 MBq 99mTechnetium-MIBI about 7 mSv. Metastable 99mTc is by far the most important nuclide used as a tracer in scintigraphy because of its short half-life, the 140 keV gamma radiation it emits, and its ability to bind to many active biomolecules. Most of this radiation is excreted after the examination. The remaining 99mTc decays rapidly to 99Tc with a half-life of 6 hours. This has a long half-life of 212,000 years and, because of the relatively weak beta radiation released during its decay, contributes only a small amount of additional radiation exposure over the remaining lifetime. In the United States alone, approximately seven million individual doses of 99mTc are administered each year for diagnostic purposes.
To reduce radiation exposure, the American Society of Nuclear Cardiology (ASNC) issued dosage recommendations in 2010. The effective dose is 2.4 mSv for 13N-ammonia, 2.5 mSv for 15O-water, 7 mSv for 18F-fluorodeoxyglucose, and 13.5 mSv for 82Rb-rubidium chloride. Compliance with these recommendations is expected to reduce the average radiation exposure to = 9 mSv. The Ordinance on Radioactive Drugs or Drugs Treated with Ionizing Radiation
regulates the approval procedures for the marketability of radioactive drugs.
Brachytherapy
Brachytherapy is used to place a sealed radioactive source inside or near the body to treat cancer, such as prostate cancer. Afterloading brachytherapy is often combined with teletherapy, which is external radiation delivered from a greater distance than brachytherapy. It is not classified as a nuclear medicine procedure, although like nuclear medicine, it uses the radiation emitted by radionuclides. After initial interest in brachytherapy in the early 20th century, its use declined in the mid-20th century because of the radiation exposure to physicians from manual handling of the radiation sources. It was not until the development of remote-controlled afterloading systems and the use of new radiation sources in the 1950s and 1960s that the risk of unnecessary radiation exposure to physicians and patients was reduced. In the afterloading procedure, an empty, tubular applicator is inserted into the target volume (e.g., the uterus) before the actual therapy and, after checking the position, loaded with a radioactive preparation. The preparation is located at the tip of a steel wire that is advanced and retracted step by step under computer control. After the pre-calculated time, the source is withdrawn into a safe and the applicator is removed. The procedure is used for breast cancer, bronchial carcinoma or oral floor carcinoma, among others. Beta emitters such as 90Sr or 106Ru or 192Ir are used. As a precaution, patients undergoing permanent brachytherapy are advised not to hold small children immediately after treatment and not to be in the vicinity of pregnant women, since low-dose radioactive sources (seeds) remain in the body after treatment with permanent brachytherapy. This is to protect the particularly radiation-sensitive tissues of a fetus or infant.
Thorium as a drug and X-ray contrast agent
Radioactive thorium was used in the 1950s and 60s to treat tuberculosis and other benign diseases (including children), with serious consequences (see Peteosthor). A stabilized suspension of colloidal thorium(IV) oxide, co-developed by António Egas Moniz (1874-1954), was used from 1929 under the trade name Thorotrast as an X-ray contrast agent for angiography in several million patients worldwide until it was banned in the mid-1950s. It accumulates in the reticulohistiocytic system and can lead to cancer due to locally increased radiation exposure. The same is true for cholangiocarcinoma and angiosarcoma of the liver, two rare liver cancers. Carcinomas of the paranasal sinuses have also been described following administration of Thorotrast. Typical onset of disease is 30–35 years after exposure. The biological half-life of Thorotrast is approximately 400 years. The largest study in this area was conducted in Germany in 2004 and showed a particularly high mortality rate among patients exposed in this way. The median life expectancy over a seventy-year observation period was 14 years shorter than in the comparison group.
Nuclear weapons and nuclear energy
Radiation effects of the atomic bomb attack and consequences for radiation protection
After the U.S. atomic bombs were dropped on Hiroshima and Nagasaki on August 6 and 9, 1945, an additional 130,000 people - in addition to the 100,000 immediate victims - died from the effects of radiation by the end of 1945. Some experienced the so-called walking ghost phase, an acute radiation sickness caused by a high equivalent dose of 6 to 20 Sievert after a lethal whole-body dose. The phase describes the period of apparent recovery of a patient between the onset of the first massive symptoms and the inevitable death. In the years that followed, a number of deaths from radiation-induced diseases were added. In Japan, the radiation-damaged survivors are called hibakusha () and are conservatively estimated to number about 100,000.
In 1946, the Atomic Bomb Casualty Commission (ABCC) was established by the National Research Council of the National Academy of Sciences by order of U.S. President Harry S. Truman to study the long-term effects of radiation on survivors of the atomic bombings. In 1975, the ABCC was replaced by the Radiation Effects Research Foundation (RERF). Organizations such as the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), founded in 1955, and the National Academy of Sciences - Advisory Committee on the Biological Effects of Ionizing Radiation (BEIR Committee), founded in 1972, analyze the effects of radiation exposure on humans on the basis of atomic bomb victims who have been examined and, in some cases, medically monitored for decades. They determine the course of the mortality rate as a function of the age of the radiation victims in comparison with the spontaneous rate, and also the dose-dependency of the number of additional deaths. To date, 26 UNSCEAR reports have been published and are available online, most recently in 2017 on the effects of the Fukushima nuclear accident.
By 1949, Americans felt increasingly threatened by the possibility of nuclear war with the Soviet Union and sought ways to survive a nuclear attack. The U.S. Federal Civil Defense Administration (USFCDA) was created by the government to educate the public on how to prepare for such an attack. In 1951, with the help of this agency, a children's educational film was produced in the U.S. called Duck and Cover, in which a turtle demonstrates how to protect oneself from the immediate effects of an atomic bomb explosion by using a coat, tablecloths, or even a newspaper.
Recognizing that existing medical capacity would not be sufficient in an emergency, dentists were called upon to either assist physicians in an emergency or, if necessary, to provide assistance themselves. To mobilize the profession with the help of a prominent representative, dentist Russell Welford Bunting (1881-1962), dean of the University of Michigan Dental School, was recruited in July 1951 as a dental consultant to the USFCDA.
The American physicist Karl Ziegler Morgan (1907-1999) was one of the founders of radiation health physics. In later life, after a long career with the Manhattan Project and Oak Ridge National Laboratory (ORNL), he became a critic of nuclear power and nuclear weapons production. Morgan was Director of Health Physics at ORNL from the late 1940s until his retirement in 1972. In 1955, he became the first president of the Health Physics Society and served as editor of the journal Health Physics from 1955 to 1977.
Nuclear fallout shelters are designed to protect for an extended period. Due to the nature of nuclear warfare, such shelters must be completely self-sufficient for long periods. In particular, because of the radioactive contamination of the surrounding area, such a facility must be able to survive for several weeks. In 1959, top-secret construction began in Germany on a government bunker in the Ahr valley. In June 1964, 144 test persons survived for six days in a civilian nuclear bunker. The bunker in Dortmund had been built during the Second World War and had been converted at great expense in the early 1960s into a nuclear-weapon-proof building. However, it would be impossible to build a bunker for millions of German citizens. The Swiss Army built about 7800 nuclear fallout shelters in 1964. In the United States in particular, but also Europe, citizens built private fallout shelters in their front yards on their initiative. This construction was largely kept secret because the owners feared that third parties might take possession of the bunker in the event of a crisis.
Fallout and contamination
On July 16, 1945, the first atomic bomb test took place near the town of Alamogordo (New Mexico, USA). As a result of the atmospheric nuclear weapons tests carried out by the United States, the Soviet Union, France, Great Britain, and China, the Earth's atmosphere became increasingly contaminated with fission products from these tests from the 1950s onwards. The radioactive fallout landed on the earth's surface and ended up in plants and, via animal feed, in food of animal origin. Ultimately, they entered the human body and could be detected in bones and teeth as strontium-90, among other things. The radioactivity in the field was measured with a gamma scope, as shown at the air raid equipment exhibition in Bad Godesberg in 1954. Around 180 tests were carried out in 1962 alone. The extent of the radioactive contamination of the food sparked worldwide protests in the early 1960s.
During World War II and the Cold War, the Hanford Site produced plutonium for U.S. nuclear weapons for more than 50 years. The plutonium for the first plutonium bomb, Fat Man, also came from there. Hanford is considered the most radioactively contaminated site in the Western Hemisphere. A total of 110,000 tons of nuclear fuel was produced there. In 1948, a radioactive cloud leaked from the plant. The amount of 131I alone was 5500 curies. Most of the reactors at Hanford were shut down in the 1960s, but no disposal or decontamination was done. After preliminary work, the world's largest decontamination operation began at Hanford in 2001 to safely dispose of the radioactive and toxic waste. In 2006, some 11,000 workers were still cleaning up contaminated buildings and soil to reduce radiation levels at the site to acceptable levels. This work is expected to continue until 2052. It is estimated that more than four million liters of radioactive liquid have leaked from storage tanks.
It was only after the two superpowers agreed on a Partial Test Ban Treaty in 1963, which allowed only underground nuclear weapons testing, that the level of radioactivity in food began to decline. Shields Warren (1896-1980), one of the authors of a report on the effects of the atomic bombs dropped on Japan, was criticized for downplaying the effects of residual radiation in Hiroshima and Nagasaki, but later warned of the dangers of fallout. Fallout refers to the spread of radioactivity in the context of a given meteorological situation. A model experiment was conducted in 2008.
The International Campaign to Abolish Nuclear Weapons (ICAN) is an international alliance of non-governmental organizations committed to the elimination of all nuclear weapons through a binding international treaty - a Nuclear Weapons Convention. ICAN was founded in 2007 by IPPNW (International Physicians for the Prevention of Nuclear War) and other organizations at the Nuclear Non-Proliferation Treaty Conference in Vienna and launched in twelve countries. Today, 468 organizations in 101 countries are involved in the campaign (as of 2017). ICAN was awarded the 2017 Nobel Peace Prize.
Radioprotectors
A radioprotector is a pharmacon that, when administered, selectively protects healthy cells from the toxic effects of ionizing radiation. The first work with radioprotectors began as part of the Manhattan Project, a military research project to develop and build an atomic bomb.
Iodine absorbed by the body is almost completely stored in the thyroid gland and has a biological half-life of about 120 days. If the iodine is radioactive (131I), it can irradiate and damage the thyroid gland in high doses during this time. Because the thyroid gland can only absorb a limited amount of iodine, prophylactic administration of non-radioactive iodine may result in iodine blockade. Potassium iodide in tablet form (colloquially known as "iodine tablets") reduces the uptake of radioactive iodine into the thyroid by a factor of 90 or more, thus acting as a radioprotector. All other radiation damage remains unaffected by taking iodine tablets. In Germany, the Potassium Iodide Ordinance (KIV) was enacted in 2003 to ensure "the supply of the population with potassium iodide-containing medicines in the event of radiological incidents".
Potassium iodide is usually stored in communities near nuclear facilities for distribution to the population in the event of a disaster. People over the age of 45 should not take iodine tablets because the risk of side effects is higher than the risk of developing thyroid cancer. In Switzerland, as a precautionary measure, tablets have been distributed every five years since 2004 to the population living within 20 km of nuclear power plants (from 2014, 50 km). In Austria, large stocks of iodine tablets have been kept in pharmacies, kindergartens, schools, the army and the federal reserve since 2002.
Thanks to the protective function of radioprotectors, the dose of radiation used to treat malignant tumors (cancer) can be increased, thereby increasing the effectiveness of the therapy. There are also radiosensitizers, which increase the sensitivity of malignant tumor cells to ionizing radiation. As early as 1921, the German radiologist Hermann Holthusen (1886-1971) described that oxygen increases the sensitivity of cells.
Nuclear accidents and catastrophes
Founded in 1957 as a sub-organization of the Organization for Economic Cooperation and Development (OECD), the Nuclear Energy Agency (NEA) pools the scientific and financial resources of participating countries' nuclear research programs. It operates various databases and also manages the International Reporting System for Operating Experience (IRS or IAEA/NEA Incident Reporting System) of the International Atomic Energy Agency (IAEA). The IAEA records and investigates radiation accidents that have occurred worldwide in connection with nuclear medical procedures and the disposal of related materials.
The International Nuclear and Radiological Event Scale (INES) is a scale for safety-related events, in particular nuclear incidents and accidents in nuclear facilities. It was developed by an international group of experts and officially adopted in 1990 by the International Atomic Energy Agency (IAEA) and the Nuclear Energy Agency of the Organization for Economic Cooperation and Development (OECD). The purpose of the scale is to inform the public quickly about the safety significance of an event by means of a comprehensible classification of events.
At the end of its useful life, the proper disposal of the remaining high activity is of paramount importance. Improper disposal of the radionuclide cobalt-60, used in cobalt guns for radiotherapy, has led to serious radiation accidents, such as the Ciudad Juárez (Mexico) radiological accident in 1983/84, the Goiânia (Brazil) accident in 1987, the Samut Prakan (Thailand) nuclear accident in 2000, and the Mayapuri (India) accident in 2010.
Eleven Therac-25 linear accelerators were built by the Canadian company Atomic Energy of Canada Limited (AECL) between 1982 and 1985 and installed in clinics in the United States and Canada. Software errors and a lack of quality assurance led to a serious malfunction that killed three patients and seriously injured three others between June 1985 and 1987 before appropriate countermeasures were taken. The radiation exposure in the six cases was subsequently estimated to be between 40 and 200 Gray; normal treatment is equivalent to a dose of less than 2 Gray.
Around 1990, about one hundred cobalt guns were still in use in Germany. In the meantime, electron linear accelerators were introduced and the last cobalt gun was decommissioned in 2000.
The Fukushima nuclear accident in 2011 reinforced the need for proper safety management and the derivation of safety indicators regarding the frequency of errors and incorrect actions by personnel, i.e., the human factor. The Nuclear Safety Commission of Japan () was a body of scientists that advised the Japanese government on nuclear safety issues. The commission was established in 1978, but was dissolved after the Fukushima nuclear disaster on September 19, 2012, and replaced by the Genshiryoku Kisei Iinkai (). It is an independent agency (gaikyoku, "external office") of the Japanese Ministry of the Environment that regulates and monitors the safety of Japan's nuclear power plants and related facilities.
As a result of the Chernobyl nuclear disaster in 1986, the IAEA coined the term "safety culture" for the first time in 1991 to draw attention to the importance of human and organizational issues for the safe operation of nuclear power plants.
After this nuclear disaster, the sand in children's playgrounds in Germany was removed and replaced with uncontaminated sand to protect children who were most vulnerable to radioactivity. Some families temporarily left Germany to escape the fallout. Infant mortality increased significantly by 5% in 1987, the year after Chernobyl. In total, 316 more newborns died that year than statistically expected. In Germany, the caesium137 inventories from the Chernobyl nuclear disaster in soil and food decrease by 2-3% each year; however, the contamination of game and mushrooms was still comparatively high in 2015, especially in Bavaria; there are several cases of game meat, especially wild boar, exceeding the limits. However, controls are insufficient.
Ocean dumping of radioactive waste
Between 1969 and 1982, conditioned low- and intermediate-level radioactive waste was disposed of in the Atlantic Ocean at a depth of about 4,000 meters under the supervision of the Nuclear Energy Agency (NEA) of the Organization for Economic Cooperation and Development (OECD) in accordance with the provisions of the European Convention on the Prevention of Marine Pollution by Dumping of Waste of All Kinds (London Dumping Convention of June 11, 1974). This was carried out jointly by several European countries. Since 1993, international treaties have prohibited the dumping of radioactive waste in the oceans. For decades, this dumping of nuclear waste went largely unnoticed by the public until Greenpeace denounced it in the 1980s.
Repository for heat-generating radioactive waste
Since the commissioning of the first commercial nuclear power plants (USA 1956, Germany 1962), various final storage concepts for radioactive materials have been proposed in the following decades, of which only storage in deep geological formations appeared to be safe and feasible within a reasonable period of time and was pursued further. Due to the high activity of the short-lived fission products, spent fuel is initially handled only under water and stored for several years in a decay pool. The water is used for cooling and also shields much of the emitted radiation. This is followed either by reprocessing or by decades of interim storage. Waste from reprocessing must also be stored temporarily until the heat has decreased enough to allow final disposal. Casks are special containers for the storage and transport of highly radioactive materials. Their maximum permissible dose rate is 0.35 mSv/h, of which a maximum of 0.25 mSv/h is due to neutron radiation. The safety of these transport containers has been discussed every three years since 1980 at the International Symposium on the Packaging and Transportation of Radioactive Materials (PATRAM).
Following various experiments, such as the Gorleben exploratory mine or the Asse mine, a working group on the selection procedure for repository sites (AkEnd) developed recommendations for a new selection procedure for repository sites between 1999 and 2002. In Germany, the Site Selection Act was passed in 2013 and the Act on the Further Development of the Site Search was passed on March 23, 2017. A suitable site is to be sought throughout Germany and identified by 2031. In principle, crystalline (granite), salt or clay rock types can be considered for a repository. There will be no "ideal" site. The "best possible" site will be sought. Mining areas and regions where volcanoes have been active or where there is a risk of earthquakes are excluded. Internationally, experts are advocating storage in rock formations several hundred meters below the earth's surface. This involves building a repository mine and storing the waste there. It is then permanently sealed. Geological and technical barriers surrounding the waste are designed to keep it safe for thousands of years. For example, 300 meters of rock will separate the repository from the earth's surface. It will be surrounded by a 100-meter-thick layer of granite, salt or clay. The first waste is not expected to be stored until 2050.
The Federal Office for the Safety of Nuclear Waste Management (BfE) took up its activities on September 1, 2004. Its remit includes tasks relating to nuclear safety, the safety of nuclear waste management, the site selection procedure including research activities in these areas and, later on, further tasks in the area of licensing and supervision of repositories.
In the USA, Yucca Mountain was initially selected as the final storage site, but this project was temporarily halted in February 2009. Yucca Mountain was the starting point for an investigation into atomic semiotics.
Atomic semiotics
The operation of nuclear power plants and other nuclear facilities produces radioactive materials that can have lethal health effects for thousands of years. It is important to note that there is no institution capable of maintaining the necessary knowledge of the dangers over such periods, and of ensuring that warnings about the dangers of nuclear waste in nuclear repositories will be understood by posterity in the distant future. A few years ago, even the capsules of the radionuclide cobalt-60, which were appropriately labeled, went unnoticed. Improper disposal led to the opening of these capsules, resulting in fatal consequences. The dimensions of time exceed previous human standards. For instance, cuneiform writing, which is only about 5000 years old (about 150 human generations), can only be understood after a long period of research and by experts. In 1981, research into the development of atomic semiotics began in the USA, in the German-speaking world, Roland Posner (1942-2020) of the Center for Semiotics at Technische Universität Berlin worked on this in 1982/83. In the USA, the time horizon for such warning signs was set at 10,000 years; later, as in Germany, it was set at a period of one million years, which would correspond to about 30,000 (human) generations. To date, no satisfactory solution to this problem has been found.
Radiation protection during flights
High-altitude radiation
In 1912, Victor Franz Hess (1883-1964) discovered (secondary) cosmic rays in the Earth's atmosphere using balloon flights. For this discovery he received the Nobel Prize in Physics in 1936. He was also one of the "martyrs" of early radiation research and had to undergo a thumb amputation and larynx surgery due to radium burns. In the United States and the Soviet Union, balloon flights to altitudes of about 30 km, followed by parachute jumps from the stratosphere, were conducted before 1960 to study human exposure to cosmic radiation in space. The American Manhigh and Excelsior projects with Joseph Kittinger (1928-2022) became particularly well known, but the Soviet parachutist Yevgeny Andreyev (1926-2000) also set new records.
High-energy radiation from space is much stronger at high altitudes than at sea level. The radiation exposure of flight crews and air travelers is therefore increased. The International Commission on Radiological Protection (ICRP) has issued recommendations for dose limits, which were incorporated into European law in 1996 and into the German Radiation Protection Ordinance in 2001. Radiation exposure is particularly high when flying in the polar regions or over the polar route. The average annual effective dose for aviation personnel was 1.9 mSv in 2015 and 2.0 mSv in 2016. The highest annual personal dose was 5.7 mSv in 2015 and 6.0 mSv in 2016. The collective dose for 2015 was about 76 person-Sv. This means that flight personnel are among the occupational groups in Germany with the highest radiation exposure in terms of collective dose and average annual dose. This group also includes frequent flyers, with Thomas Stuker holding the "record" - also in terms of radiation exposure - by reaching the 10 million mile mark with United Airlines MileagePlus on 5,900 flights between 1982 and the summer of 2011. In 2017, he passed the 18 million mile mark.
The program EPCARD (European Program Package for the Calculation of Aviation Route Dose) was developed at the University of Siegen and the Helmholtz Munich and can be used to calculate the dose from all components of natural penetrating cosmic radiation on any flight route and flight profile - also online.
Radiation protection in space
From the earliest crewed space flights to the first moon landing and the construction of the International Space Station (ISS), radiation protection has been a major concern. Spacesuits used for extravehicular activities are coated on the outside with aluminum, which largely protects against cosmic radiation. The largest international research project to determine the effective dose or effective dose equivalent was the Matryoshka experiment in 2010, named after the Russian Matryoshka dolls, because it uses a human-sized phantom that can be cut into slices. As part of Matroshka, an anthropomorphic phantom was exposed to the outside of the space station for the first time to simulate an astronaut performing an extravehicular activity (spacewalk) and determine their exposure to radiation.Microelectronics on satellites must also be protected from radiation.
Japanese scientists from the Japan Aerospace Exploration Agency (JAXA) have discovered a huge cave on the moon with their Kaguya lunar probe, which could offer astronauts protection from dangerous radiation during future lunar landings, especially during the planned stopover of a Mars mission.
As part of a human mission to Mars, astronauts must be protected from cosmic radiation. During Curiosity's mission to Mars, a Radiation Assessment Detector (RAD) was used to measure radiation exposure. The radiation exposure of 1.8 millisieverts per day was mainly due to the constant presence of high-energy galactic particle radiation. In contrast, radiation from the sun accounted for only about three to five percent of the radiation levels measured during Curiosity's flight to Mars. On the way to Mars, the RAD instrument detected a total of five major radiation events caused by solar flares. To protect the astronauts, a plasma bubble will surround the spacecraft as an energy shield and its magnetic field will protect the crew from cosmic radiation. This would eliminate the need for conventional radiation shields, which are several centimeters thick and correspondingly heavy. In the Space Radiation Superconducting Shield (SR2S) project, which was completed in December 2015, magnesium diboride was found to be a suitable material for generating a suitable force field.
Development of metrological principles of radiation protection
Dosimeter
Dosimeters are instruments used to measure radiation dose - as absorbed dose or dose equivalent - and are an important cornerstone of radiation protection.
Film dosimeter
At the October 1907 meeting of the American Roentgen Ray Society, Rome Vernon Wagner, an X-ray tube manufacturer, reported that he had begun carrying a photographic plate in his pocket and developing it every evening. This allowed him to determine how much radiation he had been exposed to. This was the forerunner of the film dosimeter. His efforts came too late, as he had already developed cancer and died six months after the conference.
In the 1920s, the physical chemist John Eggert (1891-1973) played a key role in the introduction of film dosimetry for routine personal monitoring. Since then, it has been successively improved and, in particular, the evaluation technique has been automated since the 1960s. At the same time, Hermann Joseph Muller (1890-1967) discovered mutations as genetic consequences of X-rays, for which he was awarded the Nobel Prize in 1946. At the same time, the roentgen (R) was introduced as a unit for quantitative measurement of radiation exposure.
A dosimeter for film is divided into multiple segments, each containing a light- or radiation-sensitive film surrounded by layers of copper and lead with varying thickness. The degree of radiation penetration determines whether the segment is not blackened or blackened to varying degrees. The absorbed radiation effect during the measurement time is summed up, and the radiation dose can be determined from the blackening. Guidelines for evaluation exist, with those for Germany being published in 1994 and last updated on December 8, 2003.
Particle and quantum detectors
With the invention of the Geiger gaseous ionization detector in 1913, which became the Geiger-Müller gaseous ionization detector in 1928 - named after the physicists Hans Geiger (1882-1945) and Walther Müller (1905-1979) - the individual particles or quanta of ionizing radiation could be detected and measured. Detectors developed later, such as proportional counters or scintillation counters, which not only "count" but also measure energy and distinguish between types of radiation, also became important for radiation protection. Scintillation measurement is one of the oldest methods of detecting ionizing radiation or X-rays; originally, a zinc sulfide screen was held in the path of the beam and the scintillation events were either counted as flashes or, in the case of X-ray diagnostics, viewed as an image. A scintillation counter known as a spinthariscope was developed in 1903 by William Crookes (1832-1919) and used by Ernest Rutherford (1871-1937) to study the scattering of alpha particles from atomic nuclei.
Thermoluminescence dosimeter
Lithium fluoride had already been proposed in the USA in 1950 by Farrington Daniels (1889-1972), Charles A. Boyd and Donald F. Saunders (1924-2013) for solid-state dosimetry using thermoluminescent dosimeters. The intensity of the thermoluminescent light is proportional to the amount of radiation previously absorbed. This type of dosimetry has been used since 1953 in the treatment of cancer patients and wherever people are occupationally exposed to radiation. The thermoluminescence dosimeter was followed by OSL dosimetry, which is not based on heat but on optically stimulated luminescence and was developed by Zenobia Jacobs and Richard Roberts at the University of Wollongong (Australia). The detector emits the stored energy as light. The light output, measured with photomultipliers, is then a measure of the dose.
Whole body counter
Since 2003, whole-body counters have been used in radiation protection to monitor the absorption (incorporation) of radionuclides in people who handle gamma-emitting open radioactive materials and who may be contaminated through food, inhalation of dusts and gases, or open wounds. (α and β emitters are not measurable).
Test specimen
Constancy testing is the verification of reference values as part of quality assurance in x-ray diagnostics, nuclear medicine diagnostics, and radiotherapy. National regulations specify which parameters are to be tested, which limits are to be observed, which test methods are to be used, and which test samples are to be used. In Germany, the Radiation Protection in Medicine Directive and the relevant DIN 6855 standard in nuclear medicine require regular (in some cases daily) constancy testing. Test sources are used to check the response of probe measuring stations as well as in vivo and in vitro measuring stations. Before starting the tests, the background count rate and the setting of the energy window must be checked every working day, and the settings and the yield with reproducible geometry must be checked at least once a week with a suitable test source, e.g. 137Caesium (DIN 6855-1). The reference values for the constancy test are determined during the acceptance test.
Compact test specimens for medical X-ray images were not created until 1982. Prior to this, the patient himself often served as the object for producing X-ray test images. Prototypes of such an X-ray phantom with integrated structures were developed by Thomas Bronder at the Physikalisch-Technische Bundesanstalt.
A water phantom is a Plexiglas container filled with distilled water that is used as a substitute for living tissue to test electron linear accelerators used in radiation therapy. According to regulatory requirements, water phantom testing must be performed approximately every three months to ensure that the radiation dose delivered by the treatment system is consistent with the radiation planning.
The Alderson-Rando phantom, invented by Samuel W. Alderson (1914-2005), has become the standard X-ray phantom. It was followed by the Alderson Radio Therapy (ART) phantom, which he patented in 1967. The ART phantom is cut horizontally into 2.5 cm thick slices. Each slice has holes sealed with bone-equivalent, soft-tissue-equivalent, or lung-equivalent pins that can be replaced by thermoluminescent dosimeters. Alderson is also known as the inventor of the crash test dummy.
Dose reconstruction with ESR spectroscopy of deciduous teeth
As a result of accidents or improper use and disposal of radiation sources, a significant number of people are exposed to varying degrees of radiation. Radioactivity and local dose measurements are not sufficient to fully assess the effects of radiation. To retrospectively determine the individual radiation dose, measurements are made on teeth, i.e. on biological, endogenous materials. Tooth enamel is particularly suitable for the detection of ionizing radiation due to its high mineral content (hydroxyapatite), which has been known since 1968 thanks to the research of John M. Brady, Norman O. Aarestad and Harold M. Swartz. The measurements are performed on milk teeth, preferably molars, using electron paramagnetic resonance spectroscopy (ESR, EPR). The concentration of radicals generated by ionizing radiation is measured in the mineral part of the tooth. Due to the high stability of the radicals, this method can be used for dosimetry of long past exposures.
Dose reconstruction using biological dosimetry
Since about 1988, in addition to physical dosimetry, biological dosimetry has made it possible to reconstruct the individual dose of ionizing radiation. This is especially important for unforeseen and accidental exposures, where radiation exposures occur without physical dose monitoring. Biological markers, particularly cytogenetic markers in blood lymphocytes, are used for this purpose. Techniques for detecting radiation damage include analyzing dicentric chromosomes after acute radiation exposure. Dicentric chromosomes result from defective repair of chromosome breaks in two chromosomes, resulting in two centromeres instead of one like undamaged chromosomes. Symmetric translocations, detected through fluorescence in situ hybridization (FISH), are used after chronic or long-term exposure to radiation. The micronucleus test and the premature chromosome condensation (PCC) test are available to measure acute exposure.
Measured variables and units
In principle, reducing the exposure of the human organism to ionizing radiation to zero is not possible and perhaps not even sensible. The human organism has been accustomed to natural radioactivity for thousands of years and ultimately this also triggers mutations (changes in genetic material), which are the cause of the development of life on earth. The mutation-inducing effect of high-energy radiation was first demonstrated in 1927 by Hermann Joseph Muller (1890-1967).
Three years after its establishment in 1958, the United Nations Scientific Committee on the Effects of Atomic Radiation adopted the Linear No-Threshold (LNT) model - a linear dose-effect relationship without a threshold - largely at the instigation of the Soviet Union. The dose-response relationship measured at high doses was extrapolated linearly to low doses. There would be no threshold, since even the smallest amounts of ionizing radiation would trigger some biological effect. The LNT model ignores not only possible radiation hormesis, but also the known ability of cells to repair genetic damage and the ability of the organism to remove damaged cells. Between 1963 and 1969, John W. Gofman (1918-2007) and Arthur R. Tamplin of the University of California, Berkeley, conducted research for the United States Atomic Energy Commission (USAEC, 1946-1974) investigating the relationship between radiation doses and cancer incidence. Their findings sparked a fierce controversy in the United States beginning in 1969. Starting in 1970, Ernest J. Sternglass, a radiologist at the University of Pittsburgh, published several studies describing the effect of radiation from nuclear tests and the vicinity of nuclear power plants on infant mortality. In 1971, the UASEC reduced the maximum allowable radiation dose by a factor of 100. Subsequently, nuclear technology was based on the principle of "As Low As Reasonably Achievable" (ALARA). This was a coherent principle as long as it was assumed that there was no threshold and that all doses were additive. In the meantime, a transition to "As High As Reasonably Safe" (AHARS) is increasingly being discussed. For the question of evacuation after accidents, a transition to AHARS seems absolutely necessary. In both the Chernobyl and Fukushima cases, hasty, poorly organized and poorly communicated evacuations caused psychological and physical damage to those affected - including documented deaths in the case of Fukushima. By some estimates, this damage is greater than would have been expected had the evacuation not taken place. Voices such as Geraldine Thomas therefore question such evacuations in principle and call for a transition to shelter-in-place wherever possible.
Absorbed dose and dose equivalent
The British physicist and radiologist and founder of radiobiology Louis Harold Gray (1905-1965) introduced the unit Rad (acronym for radiation absorbed dose) in the 1930s, which was renamed Gray (Gy) after him in 1978. One gray is a mass-specific quantity and corresponds to the energy of one joule absorbed by one kilogram of body weight. Acute whole-body exposures in excess of four Gy are usually fatal to humans.
The different types of radiation ionize to different degrees. Ionization is any process in which one or more electrons are removed from an atom or molecule, leaving the atom or molecule as a positively charged ion (cation). Each type of radiation is therefore assigned a dimensionless weighting factor that expresses its biological effectiveness. For X-rays, gamma and beta radiation, the factor is one, alpha radiation reaches a factor of twenty, and for neutron radiation it is between five and twenty, depending on the energy.
Multiplying the absorbed dose in Gy by the weighting factor gives the equivalent dose, expressed in Sievert (Sv). It is named after the Swedish physician and physicist Rolf Maximilian Sievert (1896-1966). Sievert was the founder of radiation protection research and developed the Sievert chamber in 1929 to measure the intensity of X-rays. He founded the International Commission on Radiation Units and Measurements (ICRU) and later became chairman of the International Commission on Radiological Protection (ICRP). The ICRU and ICRP specify differently defined weighting factors that apply to environmental measurements (quality factor) and body-related dose equivalent data (radiation weighting factor).
In relation to the body, the relevant dose term is the Organ Equivalent Dose (formerly "Organ Dose"). This is the dose equivalent averaged over an organ. Multiplied by organ-specific tissue weighting factors and summed over all organs, the effective dose is obtained, which represents a dose balance. In relation to environmental measurements, the ambient dose equivalent or local dose is relevant. Its increase over time is called the local dose rate.
Even at very low effective doses, stochastic effects (genetic and cancer risk) are expected. At effective doses above 0.1 Sv, deterministic effects also occur (tissue damage up to radiation sickness at very high doses). Correspondingly high radiation doses are now only given in units of Gy. Natural radiation exposure in Germany, with an annual average effective dose of about 0.002 Sv, is well below this range.
Tolerance dose
In 1931, the U.S. Advisory Committee on X-Ray and Radium Protection (ACXRP, now the National Council on Radiation Protection and Measurements, NCRP), founded in 1929, published the results of a study on the so-called tolerance dose, on which a scientifically based radiation protection guideline was based. Exposure limits were gradually lowered. In 1936 the tolerance dose was 0.1 R/day. The unit "R" (the X-ray) from the CGS unit system has been obsolete since the end of 1985. Since then, the SI unit of ion dose has been "coulomb per kilogram".
Relative biological effectiveness
After World War II, the concept of tolerance dose was replaced by that of maximum permissible dose and the concept of relative biological effectiveness was introduced. The limit was set in 1956 by the National Council on Radiation Protection & Measurements (NCRP) and the International Commission on Radiological Protection (ICRP) at 5 rem (50 mSv) per year for radiation workers and 0.5 rem per year for the general population. The unit Rem as a physical measure of radiation dose (from the English roentgen equivalent in man) was replaced by the unit Sv (sievert) in 1978. This was due to the advent of nuclear energy and its associated dangers. Prior to 1991, the equivalent dose was used both as a measure of dose and as a term for the body dose that determines the course and survival of radiation sickness. ICRP Publication 60 introduced the radiation weighting factor was introduced. For examples of equivalent doses as body doses, see
Order of magnitude of the dose equivalent
Order of magnitude of the local dose rate.
Banana equivalent dose
The origin of the concept of using a banana equivalent dose (BED) as a benchmark is unknown. In 1995, Gary Mansfield of the Lawrence Livermore National Laboratory found the Banana Equivalent Dose (BED) to be very useful in explaining radiation risks to the public. It is not a formally used dose.
The banana equivalent dose is the dose of ionizing radiation to which a person is exposed by eating one banana. Bananas contain potassium. Natural potassium consists of 0.0117% of the radioactive isotope 40K (potassium-40) and has a specific activity of 30,346 becquerels per kilogram, or about 30 becquerels per gram. The radiation dose from eating a banana is about 0.1 μSv. The value of this reference dose is given as "1" and thus becomes the "unit of measurement" banana equivalent dose. Consequently, other radiation exposures can be compared to the consumption of one banana. For example, the average daily total radiation exposure of a person is 100 banana equivalent doses.
At 0.17 mSv per year, almost 10 percent of natural radioactive exposure in Germany (an average of 2.1 mSv per year) is caused by the body's own (vital) potassium.
The banana equivalent dose does not take into account the fact that no radioactive nuclide is accumulated in the body through the consumption of potassium-containing foods. The potassium content of the body is in homeostasis and is kept constant.
Disregard of radiation protection
Unethical radiation experiments
The Trinity test was the first nuclear weapon explosion conducted as part of the US Manhattan Project. There were no warnings to residents about the fallout, nor information about shelters or possible evacuations.
This was followed in 1946 by tests in the Marshall Islands (Operation Crossroads), as recounted by chemist Harold Carpenter Hodge (1904-1990), toxicologist for the Manhattan Project, in his lecture (1947) as president of the International Association for Dental Research. Hodge's reputation was severely damaged by historian Eileen Welsome's 1999 Pulitzer Prize-winning book The Plutonium Files - America's Secret Medical Experiments in the Cold War. She documents horrific human experiments in which the subjects (including Hodge) were unaware that they were being used as "guinea pigs" to test the safety limits of uranium and plutonium. The experiments on the unidentified subjects were continued by the United States Atomic Energy Commission (AEC) into the 1970s.
The abuse of radiation continues to this day. During the Cold War, ethically reprehensible radiation experiments were conducted in the United States on untrained human subjects to determine the detailed effects of radiation on human health. Between 1945 and 1947, 18 people were injected with plutonium by Manhattan Project doctors. In Nashville, pregnant women were given radioactive mixtures. In Cincinnati, about 200 patients were irradiated over a 15-year period. In Chicago, 102 people received injections of strontium and caesium solutions. In Massachusetts, 57 children with developmental disorders were given oatmeal with radioactive markers. These radiation experiments were not stopped until 1993 under President Bill Clinton. But the injustice committed was not atoned for. For years, uranium hexafluoride caused radiation damage at a DuPont Company plant and to local residents. At times, the plant even deliberately released uranium hexafluoride in its heated gaseous state into the surrounding area to study the effects of the radioactive and chemically aggressive gas.
Stasi border controls
Between 1978 and 1989, vehicles were checked with 137Cs gamma sources at 17 border crossings between the German Democratic Republic and the Federal Republic of Germany. According to the Transit Agreement, vehicles could only be screened if there was reasonable suspicion. For this reason, the Ministry for State Security (Stasi) installed and operated a secret radioactive screening technology, codenamed "Technik V," which was generally used to screen all transit passengers to detect "deserters from the Republic." Ordinary GDR customs officers were unaware of the secret radioactive screening technology and were subject to strict "entry regulations" designed to "protect" them as much as possible from radiation exposure. Lieutenant General Heinz Fiedler (1929-1993), as the highest ranking border guard of the MfS, was responsible for all radiation controls. On February 17, 1995, the Radiation Protection Commission published a statement in which it said: "Even if we assume that individual persons stopped more frequently in the radiation field and that a fluoroscopy lasting up to three minutes increases the annual radiation exposure by one to a few mSv, this does not result in a dose that is harmful to health". In contrast, the designer of this type of border control calculated 15 nSv per crossing. Lorenz of the former State Office for Radiation Protection and Nuclear Safety of the GDR came up with a dose estimate of 1000 nSv, which was corrected to 50 nSv a few weeks later.
Radar systems
Radar equipment is used at airports, in airplanes, at missile sites, on tanks, and on ships. The radar technology commonly used in the 20th century produced X-rays as a technically unavoidable by-product in the high-voltage electronics of the equipment. In the 1960s and 1970s, German soldiers and technicians were largely unaware of the dangers, as were those in the GDR's National People's Army. The problem had been known internationally since the 1950s, and to the German Armed Forces since at least 1958. However, no radiation protection measures were taken, such as the wearing of lead aprons. Until about the mid-1980s, radiation shielding was inadequate, especially for pulse switch tubes. Particularly affected were maintenance technicians (radar mechanics) who were exposed to the X-ray generating parts for hours without any protection. The permissible annual limit value could be exceeded after just 3 minutes. It was not until 1976 that warning notices were put up and protective measures taken in the German Navy, and not until the early 1980s in general. As late as the 1990s, the German Armed Forces denied any connection between radar equipment and cancer or genetic damage. The number of victims amounted to several thousand. The connection was later acknowledged by the German Armed Forces and in many cases a supplementary pension was paid. In 2012, a foundation was set up to provide unbureaucratic compensation for the victims.
Radiation protection crimes
National Socialism
The harmful effects of X-rays were recognized during the National Socialist era. The function of the gonads (ovaries or testicles) was destroyed by ionizing radiation, leading to infertility. In July 1942, Heinrich Himmler (1900-1945) decided to conduct forced sterilization experiments at the Auschwitz-Birkenau concentration camp, which were carried out by Horst Schumann (1906-1983), previously a doctor in Aktion T4. Each test victim had to stand between two X-ray machines, which were arranged in such a way that the test victim had just enough space between them. Opposite the x-ray machines was a booth with lead walls and a small window. From the booth, Schumann could direct X-rays at the test victims' sexual organs without endangering himself. Human radiation castration experiments were also conducted in concentration camps under the direction of Viktor Brack (1904-1948). As part of the "Law for the Prevention of Hereditary Diseases," people were often subjected to radiation castration during interrogations without their knowledge. Approximately 150 radiologists from hospitals throughout Germany participated in the forced castration of approximately 7,200 people using X-rays or radium.
Polonium murder
On November 23, 2006, Alexander Alexanderovich Litvinenko (1962-2006) was murdered under unexplained circumstances as a result of radiation sickness caused by polonium. This was also briefly suspected in the case of Yasser Arafat (1929-2004), who died in 2004.
Radiation offenses
The misuse of ionizing radiation is a radiation offence under German criminal law. The use of ionizing radiation to harm persons or property is punishable. Since 1998, the regulations can be found in
(previously § 311a StGB old version); the regulations go back to § 41 AtG old version. In the Austrian Criminal Code, relevant criminal offenses are defined in the seventh section, "Criminal acts dangerous to the public" and "Criminal acts against the environment". In Switzerland, endangerment by nuclear energy, radioactive substances or ionizing radiation is punishable under Art. 326 of the Swiss Criminal Code and disregard of safety regulations under Chapter 9 of the Nuclear Energy Act of 21 March 2003.
Radiation protection for less energetic types of radiation
Originally, the term radiation protection referred only to ionizing radiation. Today, non-ionizing radiation is also included and is the responsibility of the Federal Office for Radiation Protection, the Radiation Protection Division of the Federal Office of Public Health and the Ministry of Climate Action and Energy (Austria). The project collected, evaluated and compared data on the legal situation in all European countries (47 countries plus Germany) and major non-European countries (China, India, Australia, Japan, Canada, New Zealand and the USA) regarding electric, magnetic and electromagnetic fields (EMF) and optical radiation (OS). The results were very different and in some cases deviated from the recommendations of the International Commission on Non-Ionizing Radiation Protection (ICNIRP).
UV light
For many centuries, the Inuit (Eskimos) have used snow goggles with narrow slits, carved from seal bones or reindeer antlers, to protect against snow blindness (photokeratitis).
In the 1960s, Australia - particularly Queensland - launched the first awareness campaign on the dangers of ultraviolet (UV) radiation in the spirit of primary prevention. In the 1980s, many countries in Europe and overseas initiated similar UV protection campaigns. UV radiation has a thermal effect on the skin and eyes and can lead to skin cancer (malignant melanoma) and eye inflammation or cataracts. To protect the skin from harmful UV radiation, such as photodermatosis, acne aestivalis, actinic keratosis or urticaria solaris, normal clothing, special UV protective clothing (SPF 40-50) and high SPF sunscreen can be used. The Australian-New Zealand Standard (AS/NZS 4399) of 1996 measures new textile materials in an unstretched and dry state for the manufacture of protective clothing worn while bathing, especially by children, and for the manufacture of shading textiles (sunshades, awnings). The UV Standard 801 assumes a maximum radiation intensity with the solar spectrum in Melbourne, Australia, on January 1 of a year (at the height of the Australian summer), the most sensitive skin type of the wearer, and under wearing conditions. As the solar spectrum in the northern hemisphere differs from that in Australia, the measurement method according to the European standard EN 13758-1 is based on the solar spectrum of Albuquerque (New Mexico, USA), which corresponds approximately to that of southern Europe.
To protect your eyes, wear sunglasses with UV protection or special goggles that also shield the sides to prevent snow blindness. A defensive reaction of the skin is the formation of a light callus, the skin's own sun protection, which corresponds to a protection factor of about 5. At the same time, the production of brown skin pigments (melanin) in the corresponding cells (melanocytes) is stimulated.
A solar control film is usually a film made of polyethylene terephthalate (PET) that is applied to windows to reduce the light and heat from the sun's rays. The film filters UV-A and UV-B radiation. Polyethylene terephthalate goes back to an invention by the two Englishmen John Rex Whinfield (1902-1966) and James Tennant Dickson in 1941.
The fact that UV-B radiation (Dorno radiation, after Carl Dorno (1865-1942)) is a proven carcinogen, but is also required for the body's own synthesis of vitamin-D3 (cholecalciferol), leads to internationally conflicting recommendations regarding health-promoting UV exposure. In 2014, based on the scientific evidence of the last decades, 20 scientific authorities, professional societies and associations from the fields of radiation protection, health, risk assessment, medicine and nutrition published a recommendation on "UV exposure for the formation of the body's own vitamin D". It was the first interdisciplinary recommendation on this topic worldwide. Using a solarium for the first time at a young age (<35 years) almost doubles the risk of developing malignant melanoma. In Germany, the use of tanning beds by minors has been prohibited by law since March 2010. As of August 1, 2012, sunbeds must not exceed a maximum irradiance of 0.3 watts per square meter of skin. Sunbeds must be labeled accordingly. The new irradiance limit corresponds to the highest UV dose that can be measured on Earth at 12 noon under a cloudless sky at the equator.
The minimum erythema dose (MED) is determined for medical applications. The MED is defined as the lowest dose of radiation that produces a barely visible erythema. It is determined 24 hours after the test irradiation. It is performed with the type of lamp intended for the therapy by applying so-called light stairs to skin that is not normally exposed to light (for example, on the buttocks).
Sun lamp
Richard Küch (1860-1915) was able to melt quartz glass - the basis for UV radiation sources - for the first time in 1890 and founded the Heraeus Quarzschmelze. He developed the first quartz lamp (sun lamp) for generating UV radiation in 1904, thus laying the foundation for this form of light therapy.
Despite the dosage problems, doctors increasingly used quartz lamps in the early 20th century. Internal medicine specialists and dermatologists were among the most eager testers. After successful treatment of skin tuberculosis, internal medicine began to treat tuberculous pleurisy, glandular tuberculosis and intestinal tuberculosis. In addition, doctors tested the effect of quartz lamps on other infectious diseases such as syphilis, metabolic diseases, cardiovascular diseases, nerve pain such as sciatica, or nervous diseases such as neurasthenia and hysteria. In dermatology, fungal diseases, ulcers and wounds, psoriasis, acne, freckles and hair loss were also treated with quartz lamps, while in gynecology, abdominal diseases were treated with quartz lamps. Rejuvenation specialists used artificial high-altitude sunlight to stimulate gonadal activity and treated infertility, impotentia generandi (inability to conceive), and lack of sexual desire by irradiating the genitals. For this purpose, Philipp Keller (1891-1973) developed an erythema dosimeter with which he measured the amount of radiation not in Finsen units (UV radiation with a wavelength λ of 296.7 nm and an irradiance E of 10−5 W/m2), but in height solar units (HSE). It was the only instrument in use around 1930, but it was not widely accepted in medical circles.
Treatment of acne with ultraviolet radiation is still controversial. Although UV radiation can have an antibacterial effect, it can also induce proliferative hyperkeratosis. This can lead to the formation of comedones ("blackheads"). Phototoxic effects may also occur. In addition, it is carcinogenic and promotes skin aging. UV therapy is increasingly being abandoned in favor of photodynamic therapy.
Laser
The ruby laser was developed in 1960 by Theodore Maiman (1927-2007) as the first laser based on the ruby maser. Soon after, the dangers of lasers were discovered, especially for the eyes and skin, due to the laser's low penetration depth. Lasers have numerous applications in technology and research as well as in everyday life, from simple laser pointers to distance measuring devices, cutting and welding tools, reproduction of optical storage media such as CDs, DVDs and Blu-ray discs, communication, laser scalpels and other devices using laser light in everyday medical practice. The Radiation Protection Commission requires that laser applications on human skin be performed only by a specially trained physician. Lasers are also used for show effects in discotheques and at events.
Lasers can cause biological damage due to the properties of their radiation and their sometimes extremely concentrated electromagnetic power. For this reason, lasers must be labeled with standardized warnings depending on the laser class. The classification is based on the DIN standard EN 60825-1, which distinguishes between ranges of wavelengths and exposure times that lead to characteristic injuries and injury thresholds for power or energy density.
The CO2-Laser was developed in 1964 by the Indian electrical engineer and physicist Chandra Kumar Naranbhai Patel (*1938) at the same time as the Nd:YAG laser (neodymium-doped yttrium aluminum garnet laser) at Bell Laboratories by LeGrand Van Uitert (1922-1999) and Joseph E. Geusic (*1931) and the Er:YAG laser (erbium-doped yttrium aluminum garnet laser) and has been used in dentistry since the early 1970s. In the hard laser field, two systems in particular are emerging for use in the oral cavity: the CO2 laser for use in soft tissue and the Er:YAG laser for use in dental hard and soft tissue. The goal of soft laser treatment is to achieve biostimulation with low energy densities.
The Commission on Radiological Protection strongly recommends that the possession and purchase of class 3B and 4 laser pointers be regulated by law to prevent misuse. This is due to the increase in dangerous dazzle attacks caused by high-power laser pointers. In addition to pilots, these include truck and car drivers, train operators, soccer players, referees, and even spectators at soccer games. Such glare can lead to serious accidents and, in the case of pilots and truck drivers, to occupational disability due to eye damage. The first accident prevention regulation was published on April 1, 1988 as BGV B2, followed on January 1, 1997 by DGUV Regulation 11 of the German Social Accident Insurance. Between January and mid-September 2010, the German Federal Aviation Office registered 229 dazzle attacks on helicopters and airplanes of German airlines nationwide. On October 18, 2017, a perpetrator of a dazzle attack on a federal police helicopter was sentenced to one year and six months in prison without parole.
Electromagnetic radiation exposure
Electrosmog is colloquially understood as the exposure of humans and the environment to electric, magnetic and electromagnetic fields, some of which are believed to have undesirable biological effects. Electromagnetic environmental compatibility (EMC) refers to the effects on living organisms, some of which are considered electrosensitive. Fears of such effects have existed since the beginning of technological use in the mid-19th century. In 1890, for example, officials of the Royal General Directorate in Bavaria were forbidden to attend the opening ceremony of Germany's first alternating current power plant, the Reichenhall Electricity Works, or to enter the machine room. With the establishment of the first radio telegraphy and its telegraph stations, the U.S. magazine The Atlanta Constitution reported in April 1911 on the potential dangers of radio telegraph waves, which, in addition to "tooth loss," were said to cause hair loss and make people "crazy" over time. Full-body protection was recommended as a preventive measure.
During the second half of the 20th century, other sources of electromagnetic fields have become the focus of health concerns, such as power lines, photovoltaic systems, microwave ovens, computer and television screens, security devices, radar equipment, and more recently, cordless telephones (DECT), cell phones, their base stations, energy-saving lamps, and Bluetooth connections. Electrified railroad lines, tram overhead lines and subway tracks are also strong sources of electrosmog. In 1996, the World Health Organization (WHO) launched the EMF (ElectroMagnetic Fields) Project to bring together current knowledge and available resources from key international and national organizations and scientific institutions on electromagnetic fields. The German Federal Office for Radiation Protection (BfS) published the following recommendation in 2006:
As of 2016, the EMF Guideline 2016 of EUROPAEM (European Academy For Environmental Medicine) on the prevention, diagnosis and treatment of EMF-related complaints and diseases applies.
Microwaves
A microwave oven, invented in 1950 by U.S. researcher Percy Spencer (1894-1970), is used to quickly heat food using microwave radiation at a frequency of 2.45 gigahertz. In an intact microwave oven, leakage radiation is relatively low due to the shielding of the cooking chamber. An "emission limit of five milliwatts per square centimeter (equivalent to 50 watts per square meter) at a distance of five centimeters from the surface of the appliance" (radiation density or power flux density) is specified. Children should not stand directly in front of or next to the appliance while food is being prepared. In addition, the Federal Office for Radiation Protection lists pregnant women as particularly at risk.
In microwave therapy, electromagnetic waves are generated for heat treatment. The penetration depth and energy distribution vary depending on the frequency of application (short waves, ultra short waves, microwaves). To achieve greater penetration, pulsed microwaves are used, each of which delivers high energy to the tissue. A pulse pause ensures that no burns occur. Metal implants and pacemakers are contraindications.
Cell phones
The discussion about possible health risks from mobile phone radiation has been controversial to date, although there are currently no valid results. According to the German Federal Office for Radiation Protection
The German Federal Office for Radiation Protection recommends, among other things, mobile phones with a low SAR (Specific Absorption Rate) and the use of headsets or hands-free devices to keep the mobile phone away from the head. There is some discussion that mobile phone radiation may increase the incidence of acoustic neuroma, a benign tumor that arises from the vestibulocochlear nerve. It should therefore be reduced. In everyday life, a mobile phone transmits at maximum power only in exceptional cases. As soon as it is near a cell where maximum power is no longer needed, it is instructed by that cell to reduce its power. Electrosmog or cell phone radiation filters built into cell phones are supposed to protect against radiation. The effect is doubtful from the point of view of electromagnetic environmental compatibility, because the radiation intensity of the cell phone is increased disproportionately in order to obtain the necessary power. The same is true for use in a car without an external antenna, as the necessary radiation can only penetrate through the windows, or in areas with poor network coverage. Since 2004, radio network repeaters have been developed for mobile phone networks (GSM, UMTS, Tetrapol) that can amplify the reception of a mobile phone cell in shaded buildings. This reduces the SAR value of the mobile phone when making calls.
The SAR value of a WLAN router is only a tenth of that of a cell phone, although this drops by a further 80% at a distance of just one meter. The router can be set so that it switches off when not in use, for example at night.
Electric fields
High-voltage power lines
Until now, electrical energy has been transported from the power plant to the consumer almost exclusively via high-voltage lines, in which alternating current flows at a frequency of 50 Hertz. As part of the energy transition, high-voltage direct current (HVDC) transmission systems are also planned in Germany. Since the amendment of the 26th Federal Immission Control Ordinance (BImSchV) in 2013, emissions from HVDC systems are also regulated by law. The limit is set to prevent interference with electronic implants caused by static magnetic fields. No limit has been set for static electric fields.
Domestic electrical installation
Ground fault interrupters are available to reduce electric fields and (in the case of current flow) magnetic fields from residential electrical installations. In plaster installations, only a small part of the electric field can escape from the wall. However, a mains disconnect switch automatically disconnects the relevant line as long as no electrical load is switched on; as soon as a load is switched on, the mains voltage is also switched on. Ground fault interrupters were introduced in 1973 and have been continuously improved over the decades. In 1990, for example, it became possible to disconnect the PEN conductor (formerly known as the neutral conductor). Circuit breakers can be installed in several different circuits, preferably in those that supply bedrooms. However, they only turn off when no continuous current consumers such as air conditioners, fans, humidifiers, electric alarm clocks, night lights, standby devices, alarm systems, chargers, and similar devices are turned on. Instead of the mains voltage, a low voltage (2-12 volts) is applied, which can be used to detect when a consumer is switched on.
Rooms can also be shielded with copper wallpaper or special wall paints containing metal, thus applying the Faraday cage principle.
Body scanner
Since about 2005, body scanners have been used primarily at airports for security (passenger) screening. Passive scanners detect the natural radiation emitted by a person's body and use it to locate objects worn or concealed on the body. Active systems also use artificial radiation to improve detection by analyzing the backscatter. A distinction is made between body scanners that use ionizing radiation (usually X-rays) and those that use non-ionizing radiation (terahertz radiation).
The integrated components operating in the lower terahertz range emit less than 1 mW (-3 dBm), so no health effects are expected. There are conflicting studies from 2009 on whether genetic damage can be detected as a result of terahertz radiation. In the U.S., backscatter x-ray scanners make up the majority of devices used. Scientists fear that a future increase in cancer could pose a greater threat to the life and limb of passengers than terrorism itself. It is not clear to the passenger whether the body scanners used during a particular checkpoint use only terahertz or also X-ray radiation.
According to the Federal Office for Radiation Protection, the few available results from investigations in the frequency range of active whole-body scanners that work with millimeter wave or terahertz radiation do not yet allow a conclusive assessment from a radiation protection perspective (as of 24 May 2017).
In the vicinity of the plant, where employees or other third parties may be present, the limit value of the permissible annual dose for a single person in the population of one millisievert (1 mSv, including pregnant women and children) is not exceeded, even in the case of permanent presence.
In the case of X-ray scanners for hand luggage, it is not necessary to set up a radiation protection area by Section §19 RöV, as the radiation exposure during a hand luggage check for passengers does not exceed 0.2 microsievert (μSv), even under unfavorable assumptions. For this reason, employees involved in baggage screening are not considered to be occupationally exposed to radiation in accordance with Section §31 X-ray Ordinance and therefore do not have to wear a dosimeter.
Radiation protection for electromedical treatment procedures
Electromagnetic alternating fields have been used in medicine since 1764, mainly for heating and increasing blood circulation (diathermy, short-wave therapy) to improve wound and bone healing. The relevant radiation protection is regulated by the Medical Devices Act together with the Medical Devices Operator Ordinance. The Medical Devices Act came into force in Germany on January 14, 1985. It divided the medical devices known at that time into groups according to their degree of risk to the patient. The Medical Devices Ordinance regulated the handling of medical devices until January 1, 2002, when it was replaced by the Medical Devices Act. When ionizing radiation is used in medicine, the benefit must outweigh the potential risk of tissue damage (justifiable indication). For this reason, radiation protection is of great importance. The design should be optimized according to the ALARA (As Low As Reasonably Achievable) principle as soon as an application is described as suitable. Since 1996, the European ALARA Network (EAN), founded by the European Commission, has been working on the further implementation of the ALARA principle in radiation protection.
Infrared radiation
Discovered around 1800 by the German-British astronomer, engineer and musician Friedrich Wilhelm Herschel (1738-1822), infrared radiation primarily produces heat. If the increase in body temperature and the duration of exposure exceed critical limits, heat damage and even heat stroke can result. Due to the still unsatisfactory data situation and the partly contradictory results, it is not yet possible to give clear recommendations for radiation protection with regard to infrared radiation. However, the findings regarding the acceleration of skin aging by infrared radiation are sufficient to describe the use of infrared radiation against wrinkles as counterproductive.
In 2011, the Institute for Occupational Safety and Health of the German Social Accident Insurance established exposure limit values to protect the skin from burns caused by thermal radiation. The IFA recommends that, in addition to the limit specified in EU Directive 2006/25/EC to protect the skin from burns for exposure times up to 10 seconds, a limit for exposure times between 10 and 1000 seconds should be applied. In addition, all radiation components in the wavelength range from 380 to 20000 nm should be considered for comparison with the limit values.
Radiation protection regulations
First radiation protection regulations
A leaflet published by the German Radiological Society (DRG) in 1913 was the first systematic approach to radiation protection. The physicist and co-founder of the society, Bernhard Walter (1861-1950), was one of the pioneers of radiation protection.
The International Commission on Radiological Protection (ICRP) and the International Commission on Radiation Units and Measurements (ICRU) were established at the Second International Congress of Radiology in Stockholm in 1928. In the same year, the first international radiation protection recommendations were adopted and each country represented was asked to develop a coordinated radiation control program. The United States representative, Lauriston Taylor of the US Bureau of Standards (NSB), formed the Advisory Committee on X-Ray and Radium Protection, later renamed the National Committee on Radiation Protection and Measurements (NCRP). The NCRP received a Congressional charter in 1964 and continues to develop guidelines to protect individuals and the public from excessive radiation. In the years that followed, numerous other organizations were established by almost every president.
Radiation protection monitoring
Individuals in professions such as pilots, nuclear physicians, and nuclear power plant workers are regularly exposed to ionizing radiation. In Germany, over 400,000 workers undergo occupational radiation monitoring to safeguard against the harmful effects of radiation. Approximately 70,000 individuals employed across various industries possess a radiation pass (distinct from an X-ray pass - see below). Individuals who may receive an annual effective dose of more than 1 millisievert during their work are required to undergo radiation protection monitoring. In Germany, the effective dose from natural radiation is 2.1 millisieverts per year. Radiation dose is measured using dosimeters, and the occupational dose limit is 20 millisieverts per year. Monitoring also applies to buildings, plant components or (radioactive) substances. These are exempted from the scope of the Radiation Protection Ordinance by a special administrative act, the exemption in radiation protection. To this end, it must be ensured that the resulting radiation exposure for an individual member of the public does not exceed 10 μSv per calendar year and that the resulting collective dose does not exceed 1 person sievert per year.
Radiation protection register
According to
all occupationally exposed persons and holders of radiation passports require a radiation protection register number (SSR number or SSRN), a unique personal identification number, as of December 31, 2018. The SSR number facilitates and improves the allocation and balancing of individual dose values from occupational radiation exposure in the radiation protection register. It replaces the former radiation passport number. It is used to monitor dose limits. Companies are obliged to deploy their employees in such a way that the radiation dose to which they are exposed does not exceed the limit of 20 millisieverts per calendar year. In Germany, about 440,000 people were classified as occupationally exposed to radiation in 2016. According to
paragraph 1, Sentence 1, "in the case of remediation and other measures to prevent and reduce exposure at radioactively contaminated sites, the person who carries out the measures himself or has them carried out by workers under his supervision must carry out an assessment of the body dose of the workers before starting the measures". Applications for SSR numbers must be submitted to the Federal Office for Radiation Protection (BfS) by March 31, 2019 for all employees currently under surveillance.
The application for the SSR number at the Federal Office and the transmission of the necessary data must be ensured following
paragraph 4 sentence 4 by
Radiation protection officer or by the
responsible person in accordance with paragraph 1 or paragraph 1 sentence 1 or by
the person responsible under
paragraph 2 or paragraph 1.
The SSR numbers must then be available for further use as part of normal communication with monitoring stations or radiation pass authorities. The SSR number is derived from the social security number and personal data using non-traceable encryption. The transmission takes place online. Approximately 420,00 persons are monitored for radiation protection in Germany (as of 2019).
Emergency responders (including volunteers) who are not occupationally exposed persons within the meaning of the Radiation Protection Act also require an SSR number retrospectively, i.e. after an operation in which they were exposed to radiation above the limits specified in the Radiation Protection Ordinance, as all relevant exposures must be recorded in the Radiation Protection Register.
Radiation protection areas
Radiation protection areas are spatial areas in which either people can receive certain body doses during their stay or in which a certain local dose rate is exceeded. They are defined in § 36 of the Radiation Protection Ordinance and in §§ 19 and 20 of the X-Ray Ordinance. According to the Radiation Protection Ordinance, radiation protection areas are divided into restricted areas (local dose rate ≥ 3 mSv/hour), control areas (effective dose > 6 mSv/year) and monitoring areas (effective dose > 1 mSv/year), depending on the hazard.
Radiological emergency response projects
Early warning systems
Germany, Austria and Switzerland, among many other countries, have early warning systems in place to protect the population.
The local dose rate measurement network (ODL measurement network) is a measurement system for radioactivity operated by the German Federal Office for Radiation Protection, which determines the local dose rate at the measurement site.
In Austria, the Radiation Early Warning System is a measurement and reporting system established in the late 1970s to provide early detection of elevated levels of ionizing radiation in the country and to enable the necessary measures to be taken. The readings are automatically sent to the central office at the Ministry, where they can be accessed by the relevant departments, such as the Federal Warning Center or the warning centers of the federal states.
NADAM (Network for Automatic Dose Alerting and Measurement) is the gamma radiation monitoring network of the Swiss National Emergency Operations Center. The monitoring network is complemented by the MADUK stations (Monitoring Network for Automatic Dose Rate Monitoring in the Environment of Nuclear Power Plants) of the Swiss Federal Nuclear Safety Inspectorate (ENSI).
Project NERIS-TP
In 2011-2014, the NERIS-TP project aimed to discuss the lessons learned from the European EURANOS project on nuclear emergency response with all relevant stakeholders.
Project PREPARE
The European PREPARE project aims to fill gaps in nuclear and radiological emergency preparedness identified after the Fukushima accident. The project aims to review emergency response concepts for long-lived releases, to address issues of measurement methods and food safety in the case of transboundary contamination, and to fill gaps in decision support systems (source term reconstruction, improved dispersion modeling, consideration of aquatic dispersion pathways in European river systems).
Project IMIS
Environmental radioactivity has been monitored in Germany since the 1950s. Until 1986, this was carried out by various authorities that did not coordinate with each other. Following the confusion during the Chernobyl reactor disaster in April 1986, measurement activities were pooled in the IMIS (Integrated Measurement and Information System) project, an environmental information system for monitoring radioactivity in Germany. Previously, the measuring equipment was affiliated to the warning offices under the name WADIS ("Warning service information system").
Project CONCERT
The aim of the CONCERT (European Joint Programme for the Integration of Radiation Protection Research) project is to establish a joint European program for radiation protection research in Europe in 2018, based on the current strategic research programs of the European research platforms MELODI (radiation effects and radiation risks), ALLIANCE (radioecology), NERIS (nuclear and radiological emergency response), EURADOS (radiation dosimetry) and EURAMED (medical radiation protection).
Project REWARD
The REWARD (Real time wide area radiation surveillance system) project was established to address the threats of nuclear terrorism, missing radioactive sources, radioactive contamination and nuclear accidents. The consortium developed a mobile system for real time wide area radiation monitoring based on the integration of new miniaturized solid state sensors. Two sensors are used: a cadmium zinc telluride (CdZnTe) detector for gamma radiation and a high efficiency neutron detector based on novel silicon technologies. The gamma and neutron detectors are integrated into a single monitoring device called a tag. The sensor unit includes a wireless communication interface to remotely transmit data to a monitoring base station, which also uses a GPS system to calculate the tag's position.
Task force for all types of nuclear emergencies
The Nuclear Emergency Support Team (NEST) is a US program for all types of nuclear emergencies of the National Nuclear Security Administration (NNSA) of the United States Department of Energy and is also a counter-terrorism unit that responds to incidents involving radioactive materials or nuclear weapons in US possession abroad. It was founded in 1974/75 under US President Gerald Ford and renamed the Nuclear Emergency Support Team in 2002. In 1988, a secret agreement from 1976 between the USA and the Federal Republic of Germany became known, which stipulates the deployment of NEST in the Federal Republic. In Germany, a similar unit has existed since 2003 with the name Central Federal Support Group for Serious Cases of Nuclear-Specific Emergency Response (ZUB).
Legal basis
As early as 1905, the Frenchman Viktor Hennecart called for special legislation to regulate the use of X-rays. In England, Sidney Russ (1879-1963) suggested to the British Roentgen Society in 1915 that it should develop its own set of safety standards, which it did in July 1921 with the formation of the British X-Ray and Radium Protection Committee. In the United States, the American X-Ray Society developed its own guidelines in 1922. In the German Reich, a special committee of the German X-Ray Society under Franz Maximilian Groedel (1881-1951), Hans Liniger (1863-1933) and Heinz Lossen (1893-1967) formulated the first guidelines after the First World War. In 1953, the employers' liability insurance associations issued the accident prevention regulation "Use of X-rays in medical facilities" based on the legal basis in § 848a of the Reich Insurance Code (RVG). In the GDR, the Occupational Safety and Health Regulation (ASAO) 950 was in effect from 1954 to 1971. It was replaced by ASAO 980 on April 1, 1971.
EURATOM
The European Atomic Energy Community (EURATOM) was founded on March 25, 1957, by the Treaty of Rome between France, Italy, the Benelux countries and the Federal Republic of Germany, and remains almost unchanged to this day. Chapter 3 of the Euratom Treaty regulates measures to protect the health of the population. Article 35 requires facilities for the continuous monitoring of soil, air and water for radioactivity. As a result, monitoring networks have been set up in all Member States and the data collected is sent to the EU's central database (EURDEP, European Radiological Data Exchange Platform). The platform is part of the EU's ECURIE system for the exchange of information in the event of radiological emergencies and became operational in 1995. Switzerland also participates in this information system.
Legal basis in Germany
In Germany, the first X-ray regulation (RGBl. I p. 88) was issued in 1941 and originally applied to non-medical companies. The first medical regulations were issued in October 1953 by the Main Association of Industrial Employer's Liability Insurance Associations as accident prevention regulations for the Reich Insurance Code. Basic standards for radiation protection were introduced by directives of the European Atomic Energy Community (EURATOM) on February 2, 1959. The Atomic Energy Act of December 23, 1959 is the national legal basis for all radiation protection legislation in the Federal Republic of Germany (West) with the Radiation Protection Ordinance of June 24, 1960 (only for radioactive substances), the Radiation Protection Ordinance of July 18, 1964 (for the medical sector) and the X-ray Ordinance of March 1, 1973. Radiation protection was formulated in § 1, according to which life, health and property are to be protected from the dangers of nuclear energy and the harmful effects of ionizing radiation and damage caused by nuclear energy or ionizing radiation is to be compensated. The Radiation Protection Ordinance sets dose limits for the general population and for occupationally exposed persons. In general, any use of ionizing radiation must be justified and radiation exposure must be kept as low as possible even below the limit values. To this end, physicians, dentists and veterinarians, for example, must provide proof every five years - by Section 18a (2) X-ray Ordinance. in the version dated April 30, 2003 - that their specialist knowledge in radiation protection has been updated and must complete a full-day course with a final examination. Specialist knowledge in radiation protection is required by the Technical Knowledge Guideline according to X-ray Ordinance. - R3 for persons who work with baggage screening equipment, industrial measuring equipment and interfering emitters. Since 2019, the regulatory areas of the previous X-ray and radiation protection ordinances have been merged in the amended Radiation Protection Ordinance.
The Radiation Protection Commission (SSK) was founded in 1974 as an advisory body to the Federal Ministry of the Interior. It emerged from Commission IV "Radiation Protection" of the German Atomic Energy Commission, which was founded on January 26, 1956. After the Chernobyl nuclear disaster in 1986, the Federal Ministry for the Environment, Nature Conservation, Nuclear Safety and Consumer Protection was established in the Federal Republic of Germany. The creation of this ministry was primarily a response to the perceived lack of coordination in the political response to the Chernobyl disaster and its aftermath. On December 11, 1986, the German Bundestag passed the Precautionary Radiation Protection Act (StrVG) to protect the population, to monitor radioactivity in the environment, and to minimize human exposure to radiation and radioactive contamination of the environment in the event of radioactive accidents or incidents. The last revision of the X-Ray Ordinance was issued on January 8, 1987. As part of a comprehensive modernization of German radiation protection law, which is largely based on Directive 2013/59/Euratom, the provisions of the X-Ray Ordinance have been incorporated into the revised Radiation Protection Ordinance.
Among many other measures, contaminated food was withdrawn from the market on a large scale. Parents were strongly advised not to let their children play in sandboxes. Some of the contaminated sand was replaced. In 1989, the Federal Office for Radiation Protection was incorporated into the Ministry of the Environment. On April 30, 2003, a new precautionary radiation protection law was promulgated to implement two EU directives on the health protection of persons against the dangers of ionizing radiation during medical exposure. The protection of workers from optical radiation (infrared radiation (IR), visible light (VIS) and ultraviolet radiation (UV)), which falls under the category of non-ionizing radiation, is regulated by the Ordinance on the Protection of Workers from Artificial Optical Radiation of 19 July 2010. It is based on the EU Directive 2006/25/EC of April 27, 2006. On March 1, 2010, the "Act on the Protection of Humans from Non-Ionizing Radiation" (NiSG), BGBl. I p. 2433, came into force, according to which the use of sunbeds by minors has been prohibited since August 4, 2009, in accordance with
A new Radiation Protection Act came into force in Germany on October 1, 2017.
In Germany, a radiation protection officer directs and supervises activities to ensure radiation protection when handling radioactive materials or ionizing radiation. Their duties are described in
of the Radiation Protection Ordinance and
of the X-Ray Ordinance. They are appointed by the radiation protection officer, who is responsible for ensuring that all radiation protection regulations are observed.
X-ray passport
Since 2002, an x-ray pass is a document in which the examining physician or dentist must enter information about the x-ray examinations performed on the patient. The main aim was to avoid unnecessary repeat examinations. According to the new Radiation Protection Ordinance (StrlSchV), practices and clinics are no longer obliged to offer their patients X-ray passports and to enter examinations in them. The Radiation Protection Ordinance came into force on December 31, 2018, together with the Radiation Protection Act (StrlSchG) passed in 2017, replacing the previous Radiation Protection Ordinance and the X-ray Ordinance. The Federal Office for Radiation Protection (BfS) continues to advise patients to keep records of their own radiation diagnostic examinations. On its website, the BfS provides a downloadable document that can be used for personal documentation.
Legal basis in Switzerland
In Switzerland, institutionalized radiation protection began in 1955 with the issuance of guidelines for protection against ionizing radiation in medicine, laboratories, industry and manufacturing plants, although these were only recommendations. The legal basis was created by a new constitutional article (Art. 24), according to which the federal government issues regulations on protection against the dangers of ionizing radiation. On this basis, a corresponding federal law entered into force on July 1, 1960. The first Swiss ordinance on radiation protection entered into force on May 1, 1963. On October 7, 1963, the Federal Department of Home Affairs (EDI) issued the following decrees to supplement the ordinance:
on radiation protection in medical X-ray equipment
on radiation protection in shoe X-ray machines (of which about 850 were in operation in 1963; the last one was not decommissioned until 1990)
on the radioactivity of luminous dials.
Another 40 regulations followed. The monitoring of such facilities took many years due to a lack of personnel. From 1963, dosimeters were to be used for personal protection, but this met with great resistance. It was not until 1989 that an updated radiation protection law was passed, accompanied by radiation protection training for the people concerned.
Legal basis in Austria
The legal basis for radiation protection in Austria is the Radiation Protection Act (BGBl. 277/69 as amended) of June 11, 1969. The tasks of radiation protection extend to the fields of medicine, commerce and industry, research, schools, worker protection and food. The General Radiation Protection Ordinance, Federal Law Gazette II No. 191/2006, has been in force since June 1, 2006. Based on the Radiation Protection Act, it regulates the handling of radiation sources and measures for protection against ionizing radiation. The Optical Radiation Ordinance (VOPST) is a detailed ordinance to the Occupational Safety and Health Act (ASchG).
On August 1, 2020, a new radiation protection law came into force, which largely harmonized the radiation protection regulations for artificial radioactive substances and terrestrial natural radioactive substances. They are now enshrined in the General Radiation Protection Ordinance 2020. Companies that carry out activities with naturally occurring radioactive substances are now subject to the licensing or notification requirements pursuant to Sections 15 to 17 of the Radiation Protection Act 2020, unless an exemption provision pursuant to Sections 7 or 8 of the General Radiation Protection Ordinance 2020 applies. Cement production including maintenance of clinker kilns, production of primary iron and tin, lead and copper smelting are included in the scope. If a company falls within the scope of the General Radiation Protection Ordinance 2020, its owner must commission an officially authorized monitoring body. The mandate includes dose assessment for workers who may be exposed to increased radiation exposure and, if necessary, determination of the activity concentration of residues and radioactive substances discharged with the air or waste water.
See also
List of civilian nuclear accidents
References
External links
Laws, ordinances, guidelines, expert opinions and publications on radiation protection , timeline since 2002 of the Federal Ministry for the Environment, Nature Conservation, Nuclear Safety and Consumer Protection. Retrieved on November 28, 2017.
Guidelines for quality assurance in radiology (PDF) German Medical Association, November 23, 2007. Retrieved December 4, 2017.
DIN Radiology Standards (PDF) DIN Radiology Standards Committee NAR in cooperation with the German Radiological Society, June 2015, accessed December 4, 2017.
Radiation protection in veterinary medicine - Guideline to the Radiation Protection Ordinance (StrlSchV) and the X-ray Ordinance (RöV) (PDF) September 25, 2014, Federal Ministry for the Environment, Nature Conservation, Building and Nuclear Safety, Division Medical-Biological Affairs of Radiation Protection Ref. RS II 4 - 11432/7. Retrieved November 28, 2017.
Radioactivity and radiation protection (PDF; 6.6 MB) Federal Office of Public Health (Switzerland), July 2007, accessed November 25, 2017.
Overview of international radiation protection associations and organizations, Austrian Association for Radiation Protection. Retrieved December 3, 2017.
Human Radiation Experiments DOE Openness. Retrieved January 10, 2018.
Department of Energy OpenNet Resources. Retrieved January 10, 2018.
Igor Gusev, Angelina Guskova, Fred A. Mettler: Medical Management of Radiation Accidents, Second Edition. CRC Press, 2001, , p. 299 ff. (English, limited preview in Google Book Search).
Bibliography
Limited preview in Google Books.
Limited preview in Google Books.
Limited preview in Google Books
Limited preview in Google Books.
Ashley W. Oughterson, Shields Warren: Medical Effects of the Atomic Bomb in Japan. Volume VIII.8 aus der National Nuclear Energy Series zum Manhattan Project, McGraw-Hill Book Company, 1956.
Carl Voegtlin, Harold C. Hodge: Pharmacology and Toxicology of Uranium Compounds. Volume VI.1, Part I and Part II (with a Section on the Pharmacology and Toxicology of Fluorine and Hydrogen Fluoride) from the National Nuclear Energy Series to the Manhattan Project, McGraw-Hill Book Company, 1949.
Henry DeWolf Smyth (written on the request of Maj. Gen. L. R. Groves): Atomic Energy for Military Purposes. The official report on the development of the atomic bomb under the auspices of the United States Government, 1940–1945. Princeton University Press, 1946.
James E. Grindler (Argonne National Laboratory): The Radiochemistry of Uranium. Nuclear Science Series, National Research Council, NAS-NS 3050, undated.
Radiation protection
History of medicine
History of dentistry
History of physics
Radiology
Radiobiology
Nuclear safety and security | History of radiation protection | [
"Chemistry",
"Biology"
] | 31,205 | [
"Radiobiology",
"Radioactivity"
] |
76,493,878 | https://en.wikipedia.org/wiki/Sufi%20Zafar | Sufi Zafar is a physicist and electrical engineer known for her research on CMOS-based biosensors. She completed her PhD in physics from Syracuse University in 1991, and works as a researcher for IBM Research at the Thomas J. Watson Research Center.
Awards and recognition
Zafar was elected as a Fellow of the American Physical Society (APS) in 2007, after a nomination from the APS Forum on Industrial & Applied Physics, "for her contribution to the understanding of electrical degradation and charge transport mechanisms in high permittivity and SiO2 dielectric thin films, with a focus on advanced CMOS and memory device applications". She was elected as an IEEE Fellow in 2023, "for contributions to CMOS-compatible biosensors and high permittivity field effect transistor reliability models".
In 2021 she received the 2021 FIAP Career Lectureship Award of the APS, "for contributions to semiconductor device-based biosensors with applications in biology, healthcare and Internet of Things (IoT)". She was a Distinguished Lecturer of the APS for 2022.
References
External links
Year of birth missing (living people)
Living people
Semiconductor physicists
Women physicists
Electrical engineers
Women electrical engineers
Syracuse University alumni
IBM employees
Fellows of the American Physical Society
Fellows of the IEEE | Sufi Zafar | [
"Engineering"
] | 266 | [
"Electrical engineering",
"Electrical engineers"
] |
76,494,117 | https://en.wikipedia.org/wiki/Gustaaf%20Van%20Tendeloo | Gustaaf Van Tendeloo (born 1950), or Staf Van Tendeloo is a Belgian physicist known for his contributions to electron microscopy, electron crystallography, and the physics of materials. In 2011, his group reported the first atomically resolved reconstruction of a nanoparticle in 3D.
Van Tendeloo was born in Lier, Belgium. He obtained his licentiate in physics from the Vrije Universiteit Brussel (VUB; 'Free University of Brussels') in 1972, followed by his doctorate from the University of Antwerp in 1974 under the supervision of Severin Amelinckx. He received an aggregation from the VUB in 1981. Since 1972, Van Tendeloo has been associated with the University of Antwerp, where he is the professor of solid-state physics. Additionally, he serves as Professor of the Physics of Materials at the University of Antwerp. In 1986 he became part-time professor at the VUB and since 1994 he has been a full professor at the University of Antwerp. Since 2003, he has been the head of the EMAT (Electron Microscopy of Materials) laboratory on electron microscopy.
Throughout his career, Van Tendeloo has undertaken significant research endeavors both domestically and internationally, including research stints at the University of California, Berkeley, University of Illinois Urbana-Champaign and the Université de Caen. He is a member of the Royal Flemish Academy of Belgium for Science and the Arts since 2010. He received the Dr. De Leeuw-Damry-Bourlart Prize from the Research Foundation – Flanders (FWO) in 2015. In 2023, He received an honorary doctorate degree from the University of Zaragoza.
Bibliography
References
Living people
1950 births
People from Lier, Belgium
Belgian physicists
Materials scientists and engineers
Vrije Universiteit Brussel alumni
University of Antwerp alumni
Academic staff of the University of Antwerp
Academic staff of Vrije Universiteit Brussel
Members of the Royal Flemish Academy of Belgium for Science and the Arts
Crystallographers | Gustaaf Van Tendeloo | [
"Chemistry",
"Materials_science",
"Engineering"
] | 412 | [
"Crystallographers",
"Crystallography",
"Materials scientists and engineers",
"Materials science"
] |
76,497,915 | https://en.wikipedia.org/wiki/IndExs%20%E2%80%93%20Index%20of%20Exsiccatae | IndExs – Index of Exsiccatae is an online biological database that plays a pivotal role in documenting more than 2,300 historical and ongoing series of exsiccatae and exsiccata-like works. Managed by the Botanische Staatssammlung München in München, IndExs serves as a comprehensive data repository for these series, providing detailed titles with information on the more than 1,300 editors, bibliographic information, exsiccatal numbers, publication timespans, ranges, information on preceding and superseding series and publishers. Exsiccatae, organised series of biological specimens distributed among biological collections, are essential resources found in major herbaria worldwide. Open access to the general information on exsiccatae facilitates global scientific engagement and research.
History and purpose
Launched in 2001, IndExs has become indispensable to herbaria, fungaria, and digitisation initiatives, catering to their evolving scientific content needs. The database categorises exsiccatae and the specimens they distribute, focusing on major organismic groups within botany and mycology. This categorisation is enhanced by images of exemplary specimen labels from more than 70 herbaria citing their Index Herbariorum´s acronyms. IndExs standardizes the naming conventions for exsiccata series.
IndExs leverages the DiversityExsiccatae module of the Diversity Workbench framework as database management system. Recently, efforts to align its technical infrastructure with Wikidata concepts have begun, indicating a move towards more integrated and semantic web-based data management practices. The main focus is on the disambiguation of names of more than 1,300 editors and the integration of information for 2,300 exsiccata series into the semantic web. This move involves adopting Wikidata identifiers for the precise identification of editors, contributing additional details to existing Wikidata entries about their scientific work, and creating new entries where necessary. A proposed new property, the "IndExs Exsiccata ID," aims to link directly to IndExs, allowing for the incorporation of exsiccata series information into Wikidata. This integration facilitates a linked data environment, ensuring that the significant contributions of botanical and mycological editors and their work are more accessible and accurately represented in global data repositories.
Applications
The practical application of IndExs is highlighted by its use in the cataloguing and analysis of the bryophyte collection at the National Herbarium in Pretoria (PRE), South Africa. In this project, IndExs was used to compile the first catalogue of exsiccatae for the PRE collection and provided the necessary framework and reference material to identify and classify the 66 exsiccatae series represented in the collection. Through IndExs, the project team was able to identify and document significant exsiccatae within the PRE collection, including rare sets like Anton Rehmann's Musci Austro-Africani and Bryophyta Antarctica exsiccata edited by Ryszard Ochyra. This case shows how IndExs facilitates the documentation and study of botanical specimens, enabling the first comprehensive catalog of exsiccatae within a major herbarium collection. Through IndExs, researchers can access information on exsiccatae, contributing to botanical research, taxonomy, and the history of botanical exploration and exchange. Similarly, the IndExs has been proposed for use as a reference list in the digitisation of German herbaria specimens and related biodiversity informatics projects. IndExs is acknowledged as useful resource to explain abbreviations and references as found on handwritten and printed herbarium labels (schedae). and is cited as information resource in reviews on historical herbaria and plant collectors like Ignaz Dörfler.
References
Herbaria
Botany
Lichenology
Bryology
Mycology
Phycology
Botanical literature | IndExs – Index of Exsiccatae | [
"Biology"
] | 784 | [
"Algae",
"Plants",
"Mycology",
"Phycology",
"Botany",
"Lichenology"
] |
76,498,336 | https://en.wikipedia.org/wiki/Finnish%20Energy%20Authority | The Finnish Energy Authority () is an expert authority within the Ministry of Economic Affairs and Employment in Finland. It was initially named Electricity Market Center (SMK) and before the most recent name change, Energy Market Authority (EMV).
Background
Electricity transmission in Finland is a natural monopoly, managed by regional transmission companies. The Energy Authority oversees these companies to ensure they do not abuse their monopoly position and overcharge their customers.
Functions
The Energy Authority's tasks include monitoring the pricing of the electricity transmission grid and natural gas markets, and maintaining Finland's national emission trading registry. The agency also provides information on electricity prices to consumers to support the competition of electricity suppliers. Additionally, the Energy Authority oversees the implementation of electricity origin guarantees, ensuring that the amount of energy sold to consumers by energy companies, such as wind energy, is produced by wind power. The Energy Authority also administers the renewable energy feed-in tariffs that came into effect in 2011.
Regarding emissions trading, the Energy Authority grants and monitors emissions permits, oversees the implementation of emissions trading, approves emissions verifiers, and acts as the auctioneer of emission allowances in Finland.
History
In early 2014, the Energy Authority adopted its current name and assumed tasks related to energy efficiency and the promotion of renewable energy from the Ministry of Economic Affairs and Employment. At that time, the Energy Authority employed 70 people. Simo Nurmi has been the Director-General since April 2015.
See also
European Union Agency for the Cooperation of Energy Regulators
References
External links
Energy Authority
Government agencies of Finland
Electric power
Energy production | Finnish Energy Authority | [
"Physics",
"Engineering"
] | 318 | [
"Power (physics)",
"Electrical engineering",
"Electric power",
"Physical quantities"
] |
76,498,404 | https://en.wikipedia.org/wiki/Compositional%20game%20theory | Compositional game theory is a branch of game theory and computer science, which aims to present large complex games as a composition of simple small games.
Motivation
A major theme in computer science is the ability to construct simple building-blocks (e.g. functions or procedures in a programming language), and compose them into larger structures (e.g. more complex functions or programs). This principle is also called modularity.
In contrast, in classic game theory, even complex games are treated as single, monolithic objects. This makes the analysis of games hard to scale.
Compositional game theory (CGT) aims to apply the modularity principle to game theory. The main motivation is to make it easier to analyze large games using software tools.
Higher-order game
A higher-order simultaneous game is a generalization of a Simultaneous game in which players are defined by selection functions rather than by utility functions. Formally, a higher-order simultaneous game for n players contains the following elements:
A set R of outcomes.
For each player i, a set Xi of choices (possible actions).
We define Σ as the Cartesian product of all Xi, and call it the set of strategy profiles.
An outcome function, from Σ to R. This function determines, for each combination of actions of the players, what the outcome will be.
For each player i, there is a selection function denoted di. The selection function takes as input a context, which is a function from Xi to R; and returns a set of best-responses, which is a subset of Xi.
The term "higher-order" comes from the latter element. The best-response correspondence of each player is a higher-order function, as is input is itself a function. Every strategy-profile s1 in Σ, defines for each player i a function from Xi to R: the function maps each possible action xi in Xi to the outcome that would result if all players except i play as in s1, whereas player i switches his action to xi. In other words, s1 defines the context in which player i operates.
Given two strategy-tuples s1 and s2 in Σ, we say that s2 is a best-response to s1 if, for each player i, s2,i is contained in the output of di on the context generated by s1. The best-response relation is a binary relation contained in Σ x Σ, denoted by B.
In a standard game, instead of the selection function, there is a utility function ui for each player i. A utility function takes as input an outcome from R, and returns a real number. Such a game can be represented as a higher-order game as follows. For each player i, the selection function returns the set of actions from Xi that maximize the utility of agent i, given the context.
Open games
The main object of study in CGT is the open game. An open game has the following elements:
A set X of observations;
A set Y of outcomes;
A set Σ of strategy profiles.
A play function P, which is a function from Σ x X to Y;
A coplay function C, which is a function from Σ x X x R to S;
A best-response function B, which is a function from X x (Y -> R) to a relation in Σ x Σ.
It is an abstraction of a higher-order game.
Open games can be decomposed in two ways:
In sequence - yielding a sequential game;
In parallel - yielding a simultaneous game.
See also
Bayesian open games.
External links
Open game engine - Haskell code for constructing and analyzing open games.
References
Game theory
Category theory | Compositional game theory | [
"Mathematics"
] | 748 | [
"Functions and mappings",
"Mathematical structures",
"Mathematical objects",
"Fields of abstract algebra",
"Game theory",
"Category theory",
"Mathematical relations"
] |
76,499,316 | https://en.wikipedia.org/wiki/NGC%206122 | NGC 6122 is a spiral galaxy located around 484 million light-years away in the constellation Corona Borealis. NGC 6122 was discovered on May 6, 1886 by the astronomer Guillaume Bigourdan, and its diameter is 211,000 light-years. NGC 6122 is not known to have much star-formation, and does not have an active galactic nucleus.
NGC 6122 has been the host of one supernova so far: SN 2003ge. It was discovered on June 21, 2003 by astronomers Tim Puckett and Alex Langoussis. It was located 8".8 west and 0".1 north of the nucleus. The supernova was Type Ia.
References
External links
6122
057858
Corona Borealis
057858
+06-36-032
Astronomical objects discovered in 1886
Discoveries by Guillaume Bigourdan | NGC 6122 | [
"Astronomy"
] | 173 | [
"Corona Borealis",
"Constellations"
] |
76,499,353 | https://en.wikipedia.org/wiki/NGC%204670 | NGC 4670 is a blue compact galaxy in the constellation Coma Berenices. The galaxy lies about 60 million light years away from Earth, which means, given its apparent dimensions, that NGC 4670 is approximately 25,000 light years across. It was discovered by William Herschel on April 6, 1785.
Characteristics
The overall shape of the galaxy is categorised as peculiar and it has been categorised as amorphous or as barred lenticular galaxy. NGC 4670 is included in the Atlas of Peculiar Galaxies in the galaxies with diffuse counter tails category. The gas kinematics indicate the presence of a central bar. The galaxy is seen with an 28° inclination but it is possibly warped.
NGC 4670 is characterised by its blue color, which was noted by Guillermo Haro in a study published in 1956. Such galaxies are characterised by episodes of intense star formation. The centre of NGC 4670 hosts a supergiant HII region and also hosts most of the hydrogen of the galaxy. The hydrogen lies in three clouds with an estimated mass of . Four other HII regions are visible near the central region.
The galaxy has also ionised gas outside of the central region, forming bubbles and filaments. The two larger filaments extend to the southwest and northeast and a have a calculated length of 7.5 and 6.5 kpc respectively.
An X-ray and radio source has been detected in the galaxy at the location of a star cluster complex but its nature is uncertain. It could be a massive black hole, an ultraluminous X-ray bubble, an X-ray binary star or a supernova remnant.
Nearby galaxies
NGC 4670 is considered to be a member of the NGC 4565 Group, which also includes, apart from NGC 4565, the galaxies NGC 4494, NGC 4562, NGC 4725, and NGC 4747.
References
External links
Barred lenticular galaxies
Starburst galaxies
Peculiar galaxies
Coma Berenices
4670
07930
163
42987
Discoveries by William Herschel
Astronomical objects discovered in 1785
+05-30-072
12428+2724 | NGC 4670 | [
"Astronomy"
] | 434 | [
"Coma Berenices",
"Constellations"
] |
76,500,027 | https://en.wikipedia.org/wiki/Nanobubble | A nanobubble is a small sub-micrometer gas-containing cavity, or bubble, in aqueous solutions with unique properties caused by high internal pressure, small size and surface charge. Nanobubbles generally measure between 70-150 nanometers in size and less than 200 nanometers in diameter and are known for their longevity and stability, low buoyancy, negative surface charge, high surface area per volume, high internal pressure, and high gas transfer rates.
Nanobubbles can be formed by injecting any gas into a liquid. Because of their unique properties, they can interact with and affect physical, chemical, and biological processes. They have been used in technology applications for industries such as wastewater, environmental engineering, agriculture, aquaculture, medicine and biomedicine, and others.
Background
Nanobubbles are nanoscopic and generally too small to be observed using the naked eye or a standard microscope, but can be observed using backscattering of light using tools such as green laser pointers. Stable nanobubbles in bulk about 30-400 nanometers in diameter were first reported in the British scientific journal Nature in 1982. Scientists found them in deep water breaks using sonar observation.
In 1994, a study by Phil Attard, John L. Parker, and Per M. Claesson further theorized about the existence of nano-sized bubbles, proposing that stable nanobubbles can form on the surface of both hydrophilic and hydrophobic surfaces depending on factors such as the level of saturation and surface tension.
Nanobubbles can be generated using techniques such as solvent exchange, electrochemical reactions, and immersing a hydrophobic substrate into water while increasing or decreasing the water’s temperature.
Nanobubbles and nanoparticles are often found together in certain circumstances, but they differ in that nanoparticles have different properties such as density and resonance frequency.
The study of nanobubbles faces challenges in understanding their stability and the mechanisms behind their formation and dissolution.
Properties
Nanobubbles possess several distinctive properties:
Stability: Nanobubbles are more stable than larger bubbles due to factors such as surface charge and contaminants that reduce interfacial tension, allowing them to remain in liquids for extended periods.
High Internal Pressure: The small size of nanobubbles leads to high internal pressure, which influences their behavior and interactions with the surrounding liquid.
Large Surface-to-Volume Ratio: This property is crucial for efficient gas transfer between the nanobubbles and the liquid, which is beneficial for various applications.
Usage
In aquaculture, nanobubbles have been used to improve fish health and growth rates and to enhance oxidation. Nanobubbles can improve health outcomes for fish by increasing the dissolved oxygen concentration of water, reducing the concentration of bacteria and viruses in water, and triggering the nonspecific defense system of species such as the Nile tilapia, improving survivability during bacterial infections. The use of nanobubbles to increase dissolved oxygen levels can also promote plant growth and reduce the need for chemicals. Nanobubbles have also been shown as effective in increasing the metabolism of living organisms including plants. In regards to oxidation, nanobubbles are known for generating reactive oxygen species, giving them oxidative properties exceeding hydrogen peroxide. Researchers have also proposed nanobubbles as a low-chemical alternative to chemical-based oxidants such as chlorine and ozone.
References
Fluid mechanics
Bubbles (physics) | Nanobubble | [
"Chemistry",
"Engineering"
] | 717 | [
"Bubbles (physics)",
"Foams",
"Civil engineering",
"Fluid mechanics",
"Fluid dynamics"
] |
76,501,472 | https://en.wikipedia.org/wiki/Colored%20Symmetry%20%28book%29 | Colored Symmetry is a book by A.V. Shubnikov and N.V. Belov and published by Pergamon Press in 1964. The book contains translations of materials originally written in Russian and published between 1951 and 1958. The book was notable because it gave English-language speakers access to new work in the fields of dichromatic and polychromatic symmetry.
Structure and topics
The book is divided into two parts. The first part is a translation into English of A.V. Shubnikov's book Symmetry and antisymmetry of finite figures (Russian: Симметрия и антисимметрия конечных фигур) originally published in 1951. As the editor says in his preface, this book rekindled interest in the field of antisymmetry after a break of 20 years. The book defines symmetry elements, operations and groups; it then introduces the concept of antisymmetry, and derives the full set of dichromatic three-dimensional point groups. A paper entitled Antisymmetry of textures is appended to part 1; it analyzes the antisymmetry of groups containing infinity-fold axes.
The second part, entitled Infinite groups of colored symmetry, consists of translations of six papers by N.V. Belov and his co-workers in the new field of polychromatic symmetry. These papers cover the derivation of the 42 magnetic Bravais lattices and the 1651 magnetic space groups, the 46 dichromatic plane groups, mosaics for the 46 dichromatic plane groups, one-dimensional infinite crystallographic groups, polychromatic plane groups, and three-dimensional mosaics with colored symmetry.
Audience
The book is written for crystallographers, mathematicians and physics researchers who are interested in the application of color symmetry to crystal structure analysis and physics experiments involving magnetic or ferroelectric materials.
Reception
The book had a mixed reception from reviewers. Allen Nussbaum in American Scientist praised the editor for constructing a consistent story from the original works, but criticised the papers in part two for being difficult to read. G.S. Pawley in a review for Science Progress gave credit to the editor for adding the international notation next to the authors' "retrograde personal notation". However, he criticised claims that the book is a "valuable reference book" as being "optimistic". Martin Buerger in an extensive review for Science also offered both praise and criticism. He stated that previous work in the field by William Barlow and H.J. Woods is not given sufficient credit by the authors and is largely missing from the, otherwise full, bibliography. He praised Shubnikov's book (part 1) as being "very clearly written, well illustrated, and easy to understand", but criticised Belov's papers in part 2 because they "lack a central unifying theme." R.J. Davis in a brief review in Mineralogical Magazine said "this book is therefore unique in English and forms an essential introduction to modern developments in symmetry theory."
Influence
In later reviews of the literature by R.L.E. Schwarzenberger and by Branko Grünbaum and G.C. Shephard in their book Tilings and patterns the work of the Russian color symmetry school led by A.V. Shubnikov and N.V. Belov was put into its proper historical context. Schwarzenberger, and Grünbaum and Shephard, give credit to Shubnikov and Belov for relaunching the field of color symmetry after the work of Heinrich Heesch and H.J. Woods in the 1930s was largely ignored. However, they criticise Shubnikov and Belov for taking a crystallographic rather than a group-theoretic approach, and for using their own confusing notation rather than adopting the international standard Hermann–Mauguin notation for crystallographic symmetry elements.
References
External links
'' at the Internet Archive
Mathematics books
1964 non-fiction books
Symmetry | Colored Symmetry (book) | [
"Physics",
"Mathematics"
] | 835 | [
"Geometry",
"Symmetry"
] |
76,501,937 | https://en.wikipedia.org/wiki/Hong%20Liang | Hong Liang is a Chinese-American surface and interface scientist whose research focuses on structure and properties of nanoparticles and their tribological applications. She is Oscar S. Wyatt Jr. Professor and professor of mechanical engineering at Texas A&M University, president of the Society of Tribologists and Lubrication Engineers, and editor-in-chief of Tribology International.
Research
Liang's research focuses on materials science, tribology, and nanotechnology, converging in the field of nanotribology, which studies friction, wear, lubrication, and interfaces. The applications she has applied include nanoparticle lubricants and polishing agents, the use of gold nanoparticles as antibiotics, the use of luminous nanoparticles in fluorescence imaging for cancer diagnosis, and the use of plant-based lignin nanoparticles in supercapacitor-based electrical storage.
Beyond nanotechnology, Liang has also experimented with titanium gold alloys for fabricating super-hard and smooth ends of artificial joints, and with hybrid microrobots that fuse electronics with living cockroaches, allowing electronic control of the insect's nervous system and body.
Education and career
Liang has a bachelor's degree from the Beijing Steel and Iron Institute, now the University of Science and Technology Beijing. She studied materials science as a graduate student at the Stevens Institute of Technology, where she earned a master's degree in 1987 and completed her Ph.D. in 1992, with Traugott Fischer as her doctoral advisor.
After postdoctoral research with Said Jahanmir at the National Institute of Standards and Technology, she took a faculty position at the University of Alaska Fairbanks in 1998. In 2004, she moved to her present position at Texas A&M University, where she was Charles H. Barclay Jr. 45 Faculty Fellow and was named the Oscar S. Wyatt Jr. Professor in 2017. She took a leave in 2018–2019 to serve as ASME Foundation Swanson Fellow in the National Institute of Standards and Technology, where she served as assistant director of research partnerships for the Advanced Manufacturing National Program.
She was elected as president of the Society of Tribologists and Lubrication Engineers, for the 2023–2024 term, and has been co-editor-in-chief of Tribology International since 2015.
Books
Liang is the coauthor of Tribology in Chemical-Mechanical Planarization (with David Craven, Taylor & Francis, 2004). Her edited volumes include Mechanical Tribology: Materials, Characterization, and Applications (with George E. Totten, Marcel Dekker, 2004).
Recognition
Liang was named an ASME Fellow in 2009. She is also a fellow of the Society of Tribologists and Lubrication Engineers.
References
External links
Home page and Surface Science Laboratory
Living people
American nanotechnologists
American mechanical engineers
American women engineers
Chinese nanotechnologists
Chinese mechanical engineers
Chinese women engineers
Tribologists
Women materials scientists and engineers
Women mechanical engineers
University of Science and Technology Beijing alumni
Stevens Institute of Technology alumni
University of Alaska Fairbanks faculty
Texas A&M University faculty
Fellows of the American Society of Mechanical Engineers
Year of birth missing (living people) | Hong Liang | [
"Materials_science",
"Technology"
] | 657 | [
"Tribology",
"Tribologists",
"Materials scientists and engineers",
"Women materials scientists and engineers",
"Women in science and technology"
] |
64,788,226 | https://en.wikipedia.org/wiki/Luzene%20Hill | Caroline Luzene Hill (born 1946) is a Native American multimedia artist and citizen of the Eastern Band of Cherokee Indians. She combines performance with installation to reflect on violence against women, using lyrical abstraction to approach difficult topics. She is best known for her 2011-2015 work Retracing the Trace, an installation reflecting on the prevalence and pain of sexual assault through the lens of Hill's own experience. Her works primarily explore themes of the trauma and shame produced by various types of violence enacted against women and indigenous cultures and the transformative healing powers of art. Beyond the United States, Hill's art has exhibited internationally in Canada, Russia, Japan, and the United Kingdom.
Early life and education
Caroline Luzene Hill received the name "Luzene" through her paternal Cherokee grandmother. She grew up in Atlanta with her European mother and her family. Hill explained that because her father's parents were sent to Carlisle Indian Industrial School in Pennsylvania where they faced severe punishment for speaking their native language, her grandparents never spoke or taught Cherokee to their own children or grandchildren, despite teaching them to have pride in their heritage.
Hill began studying art in her early thirties, but did not pursue her art in earnest until her late forties, due to familial obligations. In 2006, she moved to Western North Carolina in order to focus on art, deepen her understanding of her Cherokee heritage, and learn more about the endangered Cherokee language.
Hill completed a Master of Fine Arts degree at Western Carolina University in 2012, and Retracing the Trace was part of her Master's project. In her thesis, Hill explained that each cord contained between one and 3,780 knots, representing the estimated numbers of rapes that go unreported in the United States every day. Elaborating on the use of these knotted and crimson-dyed cords, Hill stated that "They aren't being counted by our justice system, but I'm counting them. Each cord, like each woman, is unique." Likewise, her use of South American qhipu knotting tradition connected the silencing of sexual assault survivors to the silencing of indigenous cultures. In developing Retracing the Trace, Hill found inspiration in the work of a handful of other women artists who, similarly, explored themes of abuse and trauma, including Suzanne Lacy, Kara Walker, and Tracey Emin as well as the ideas of Jacques Lacan.
Artistic works
Hill's work explores trauma, violence against women, and the healing power of art. Her first exhibit, In de Soto's Path, happened in 1997 at the Santa Fe Indian Market. Some of Hill's earlier works also drew on Cherokee creation myths to explore linkages between sexuality, fulfillment, pain, and birth, presenting indigenous American art as connected to contemporary and universal, rather than strictly historical, themes.
Her most famous work, Retracing the Trace, reflected her own experience as a rape survivor. The installation featured Hill laying in the middle of thousands of red cords tied into quipu knots. After Hill rose from the pile of strewn knots, her silhouette remained on the floor, the outline mirroring the imprint her own body left in the mud and leaves after her own rape. Over the course of ten days, Hill returned to the gallery, rearranging and affixing each knotted cord to a new position on the gallery walls until a new trace, this one of her own creation, encircled the space.
Hill uses carmine to dye her works the signature crimson red that features so prominently in many of her works. In addition to being reminiscent of blood, the production of this particular dye by female cochineal insects to deter predators, also resonates with the major themes of Hill's work. Indigenous South American cultures used this dye during pre-colonial times in protection ceremonies and in creating protective objects.
Artist and art scholar Tania Abramson saw Hill's art part of a tradition of "female artists who were victims of sexual violence as mediums of enduring transformation, agents of shifting kaleidoscopes that dance between shame and resurrection, humiliation and insight, rage and imagination."
After receiving a Eiteljorg Museum Contemporary Art Fellowship and First Peoples Fund Fellowship in 2015, Hill collaborated with Frank Brannon of Speakeasy Press to produce a fine art book, called Spearfinger, printed solely in Cherokee syllabary. Hill discovered the story of Spearfinger, a frightening character from Cherokee myth who eats the livers of children, in James Mooney's History, Myths and Sacred Formulas of the Cherokee.
Hill met Cherokee Nation artist Brenda Mallory in 2015 and, two years later, they co-exhibited Connecting Lines at the Portland Art Museum's Center for Contemporary Native Art.
In 2019, Hill received the Ucross Fellowship for Native American Visual Artists.
Personal life
In 1994, Hill experienced a brutal rape, involving being strangled by her jacket's cord, while jogging in an Atlanta park. The details of this event later informed Hill's art and particularly her most notable work, Retracing the Trace.
Hill is an enrolled member of the Eastern Band of Cherokee Indians. She lives in Atlanta, Georgia.
References
External links
Luzene Hill personal website
WABE Interview with Luzene Hill about Now that the Gates of Hell are Closed exhibit
1946 births
Living people
Multimedia artists
Artists from Georgia (U.S. state)
American feminist artists
Eastern Band Cherokee women artists
Eastern Band Cherokee artists
Native American installation artists
20th-century Native American artists
21st-century Native American artists
20th-century Native American women
21st-century Native American women | Luzene Hill | [
"Technology"
] | 1,128 | [
"Multimedia",
"Multimedia artists"
] |
64,789,278 | https://en.wikipedia.org/wiki/When%20Topology%20Meets%20Chemistry | When Topology Meets Chemistry: A Topological Look At Molecular Chirality is a book in chemical graph theory on the graph-theoretic analysis of chirality in molecular structures. It was written by Erica Flapan, based on a series of lectures she gave in 1996 at the Institut Henri Poincaré, and was published in 2000 by the Cambridge University Press and Mathematical Association of America as the first volume in their shared Outlooks book series.
Topics
A chiral molecule is a molecular structure that is different from its mirror image. This property, while seemingly abstract, can have big consequences in biochemistry, where the shape of molecules is essential to their chemical function, and where a chiral molecule can have very different biological activities from its mirror-image molecule. When Topology Meets Chemistry concerns the mathematical analysis of molecular chirality.
The book has seven chapters, beginning with an introductory overview and ending with a chapter on the chirality of DNA molecules.
Other topics covered through the book include the rigid geometric chirality of tree-like molecular structures such as tartaric acid, and the stronger topological chirality of molecules that cannot be deformed into their mirror image without breaking and re-forming some of their molecular bonds. It discusses results of Flapan and Jonathan Simon on molecules with the molecular structure of Möbius ladders, according to which every embedding of a Möbius ladder with an odd number of rungs is chiral while Möbius ladders with an even number of rungs have achiral embeddings. It uses the symmetries of graphs, in a result that the symmetries of certain graphs can always be extended to topological symmetries of three-dimensional space, from which it follows that non-planar graphs with no self-inverse symmetry are always chiral. It discusses graphs for which every embedding is topologically knotted or linked. And it includes material on the use of knot invariants to detect topological chirality.
Audience and reception
The book is self-contained, and requires only an undergraduate level of mathematics. It includes many exercises, making it suitable for use as a textbook at both the advanced undergraduate and introductory graduate levels. Reviewer Buks van Rensburg describes the book's presentation as "efficient and intuitive", and recommends the book to "every mathematician or chemist interested in the notions of chirality and symmetry".
References
Application-specific graphs
Chirality
Mathematical chemistry
Mathematics books
2000 non-fiction books | When Topology Meets Chemistry | [
"Physics",
"Chemistry",
"Mathematics",
"Biology"
] | 503 | [
"Pharmacology",
"Origin of life",
"Biochemistry",
"Drug discovery",
"Applied mathematics",
"Stereochemistry",
"Chirality",
"Molecular modelling",
"Mathematical chemistry",
"Theoretical chemistry",
"Asymmetry",
"Biological hypotheses",
"Symmetry"
] |
64,789,599 | https://en.wikipedia.org/wiki/%CE%93-Carboline | γ-Carboline (5H-pyrido[4,3-b]indole), is a nitrogen containing heterocycle. A large number of derivatives are known with varying pharmacological properties.
See also
β-carboline
References
Gamma-Carbolines | Γ-Carboline | [
"Chemistry"
] | 61 | [
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
64,789,749 | https://en.wikipedia.org/wiki/List%20of%20game%20controllers | The following is a list of game controllers. It includes input devices that are notable and whose primary function is to control how the video games are played. Regional variants and models containing insignificant changes are not included.
Controllers
Mice
The following is a list of gaming mice, mice which are designed specifically to play games:
See also
N-Control Avenger, an attachment for video game controllers
Notes
References
game controllers
game controllers | List of game controllers | [
"Technology"
] | 83 | [
"Computing-related lists",
"Lists of computer hardware",
"Video game lists"
] |
64,790,073 | https://en.wikipedia.org/wiki/Funge | or (Angola) or (Congo -
DCR and the Congo Republic) is a traditional African swallow made of cassava flour whisked into boiling water. It can also be made with sorghum, maize, or millet. It can be served with textured vegetable, fish, or meat stew, as well as other vegetable, meat, and fish dishes. Funge is a staple food in African cuisine. Some richer and more flavorful versions may be made with stock, like fish stock, instead of water. It is also known as (literally "food").
Funge is eaten with the fingers, and a small ball of it can be dipped into an accompanying stew, side dish or sauce.
Funge is a traditional staple in Angolan cuisine. In the Lesser Antilles, a similar food is known as fungi or cou-cou.
In Ghana there are two variations, usually made with ground corn, though the variation known as banku is sometimes made from a mixture of grated cassava and corn. The corn is allowed to ferment before it is cooked. To make banku the fermented mixture is cooked in a pot, but the variation called kenkey is only partially cooked before it is wrapped in banana leaves or corn husks and steamed.
In Brazilian cuisine, a similar dish made with cassava flour and fish stock is known as .
References
Angolan cuisine
Cassava dishes
Fermented foods
Ghanaian cuisine
Swallows (food) | Funge | [
"Biology"
] | 300 | [
"Fermented foods",
"Biotechnology products"
] |
64,790,461 | https://en.wikipedia.org/wiki/Morse%20Micro | Morse Micro is a Sydney-based developer of Wi-Fi HaLow microprocessors; chips that enable high data rates, with long range and low power consumption. Amongst all Wi-Fi HaLow systems on a chip, Morse Micro processors are reported to be the smallest, fastest, longest-range with lowest-power-use.
The main application of the technology is machine-to-machine communications. With the Internet of things expected to extend to 30 billion devices by 2025, this represents a steeply growing number of users of the technology. The founders plan to be part of "expanding Wi-Fi so it can go into everything, every smoke alarm, every camera."
The firm has its global HQ in Sydney, which is also its main base for R&D, with additional centres in the United States, China, India, the United Kingdom and, from 2024, an operations centre in Taiwan. As of 2022, Morse Micro was producing more semiconductors than any other Australian-based tech company.
Technology
After eight years' development, the company's Wifi HalLow processor was reported to deliver 10 times the range of conventional Wi-Fi technology, and able to function for several years before needing battery change.
Data rates and range
The microprocessor allows for a range of data rates, depending on the modulation and coding scheme (MCS) used. This can be as low as 150 kilobits per second (Kbps) using MCS10 with BPSK modulation, to a top rate of 4 megabits per second (Mbps) using MCS9 at 256 quadrature amplitude modulation.
The chip uses low-bandwidth wireless network protocols, operating in the 1 GHz spectrum, while providing a communications range of 1,000 metres. In one field test, researchers found the technology could sustain high speed data transmission between a device placed by the north end of Sydney Harbour Bridge and a device across the harbour at Sydney Opera House. The company claims their chip provides 10 times the range, 100 times the area and 1000 times the volume of data offered by traditional wi-fi.
Connectivity and energy
To enable networked communications between machines, a single Wi-Fi HaLow Access Point can securely connect up to 8,191 devices. Applications for the WiFi HaLow technology includes the Internet of things, which may include solutions for in the home (such as lighting, monitoring and smart door locks) and in industry (such as vehicle management, high-end security and supply chain asset tracking. Looking at its scalability, one American technical review made this assessment:That's ample capacity to connect every LED bulb, light switch, smart door lock, motorized window shade, thermostat, smoke detector, solar panel, security camera, or any imaginable smart-home device for the foreseeable future. Physically, the company's microchip is one-fifth the size of a traditional Wi-Fi processor. It uses very little energy, consuming a fraction of the power consumed by traditional chips, which is achieved by periodically waking and reporting. As such, the chips can operate for several years on a single coin-size battery. In 2020, the first generation of Morse Micro microchips went into production in Taiwan. The company has onshore design and fabrication of composite semiconductors in Australia, which has been assessed as a strategic capability.
As of late 2022, the market for Wi-Fi Ha Low products appeared to be expanding, from those developing industrial IoT in the Japanese market which, "deploy thousands of devices in warehouses which use sensors and actuators."
History
"Wi-Fi was invented over 20 years ago in Australia and over that time we have seen it go into every laptop, phone and tablet, and all of that came from people in Australia. Today we are opening it up and expanding Wi-Fi so it can go into everything, every smoke alarm, every camera." — Andrew Terry, founder, speaking to The Sydney Morning Herald in 2017The founding partners of Morse Micro, Andrew Terry and Michael De Nil met while working for Broadcom, the largest supplier of integrated circuits for communications. De Nil said they noticed that chips designed for phones and laptops were being used for machine-to-machine communication and "that wasn't working very well." They decided to create a new kind of microprocessor, specifically for the Internet of things.
Morse Micro Pty Ltd was established as a private company, limited by guarantee, in August 2016. The founders were later joined by several significant engineers, including:
Professor Neil Weste the founder of Radiata Networks who had created the first 802.11a Wi-Fi chip
Dr. John O'Sullivan (engineer) radio astronomer who led the team who invented Wi-Fi at CSIRO in the 1980s
Dr. David Goodall, a design engineer at Radiata, which created the first commercial WiFi chip
By late 2023, the company employed 180 people across Australia, the United States, China, India, UK, Singapore and Taiwan. From this point the focus of market expansion became Japan, through its Japanese investor MegaChips. Security cameras became a key application, which was recognised with the global industry award, the IoT Product of the Year, in 2022 and 2023. The Australian Financial Review reported from 2024 that Morse Micro was ameliorating for geopolitical risk by maintaining two supply chains for chips and components, one from mainland China, the other Taiwan, with assembly and warehousing in Singapore. The Singapore facility began operations in August 2023, and had produced over 2 million chips by November of that year.
Investors
The Australian Government provided the founders with seed funding in 2017 as they believed Morse Micro has the "first WiFi HaLow silicon chip that securely connects smart devices over long distances." It is reported to be the best-funded Wi-Fi HaLow technology companies, with large investors from Japan, the United States and a spread of Australian retirement funds. By 15 February 2023, the company had an estimated value of US$700 million, just over A$1 billion.
Series A investment, 2019
In May 2019, Series A funding was provided in by a suite of investors. These included the Clean Energy Innovation Fund and CSIRO Innovation Fund, part of the Australian scientific research agency credited with inventing Wi-Fi in 1997. Investment also came from American entrepreneur Ray Stata of Analog Devices, Blackbird Ventures, Main Sequence Ventures, Right Click Capital, Kim Jackson and her husband Scott Farquhar through Skip Capital, Lucy and Malcolm Turnbull; and Uniseed, the venture fund of UniSuper. This tranche totalled A$42 million.
Series B investment 2022
By September 2022 the company had announced its Series B round of A$140 million, later extended to A$170 million, attracting intense investor interest. The investment round was led by Japanese chip design and manufacturing giant MegaChips, with further investment from its incumbent investors, which is known to include several Australian superannuation groups, such as TelstraSuper, HESTA, Hostplus and NGS (managed by Blackbird Ventures) and UniSuper (managed by Uniseed).
References
External links
Australian companies established in 2016
Companies based in Sydney
Network protocols
Machine to machine
Wireless communication systems
CSIRO people
Australian inventions
Wireless networking
Internet of things
Broadcom
Integrated circuits
IEEE 802.11 | Morse Micro | [
"Technology",
"Engineering"
] | 1,513 | [
"Computer engineering",
"Wireless networking",
"Computer networks engineering",
"Wireless communication systems",
"Integrated circuits"
] |
64,791,009 | https://en.wikipedia.org/wiki/Trastuzumab/hyaluronidase | Trastuzumab/hyaluronidase, sold under the brand name Herceptin SC among others, is a fixed-dose combination medication for the treatment of HER2-overexpressing breast cancer in adults. It is a combination of trastuzumab and hyaluronidase.
The most common adverse reactions include fatigue, arthralgia, diarrhea, injection site reaction, upper respiratory tract infection, rash, myalgia, nausea, headache, edema, flushing, pyrexia, cough, and pain in extremity.
Trastuzumab/hyaluronidase was approved for medical use in the European Union in August 2013. Trastuzumab/hyaluronidase was approved for medical use in the United States in February 2019.
Medical uses
Trastuzumab/hyaluronidase is indicated for adjuvant treatment of adults with HER2 overexpressing node positive or node negative (ER/PR negative or with one high risk feature; and it is indicated in combination with paclitaxel for first-line treatment of HER2-overexpressing metastatic breast cancer.
History
Trastuzumab/hyaluronidase (Herceptin SC) was approved for medical use in the European Union in August 2013.
Trastuzumab/hyaluronidase (Herceptin Hylecta) was approved for medical use in the United States in February 2019.
Approval of trastuzumab/hyaluronidase was based on two randomized trials, HannaH (NCT00950300) and SafeHER (NCT01566721). In HannaH, 596 participants with HER2-positive operable or locally advanced breast cancer, including inflammatory breast cancer, were randomized to receive 8 cycles of either trastuzumab/hyaluronidase or intravenous trastuzumab concurrently with chemotherapy, followed by surgery and continued therapy with either trastuzumab/hyaluronidase or intravenous trastuzumab, for an additional 10 cycles. HannaH demonstrated comparability between trastuzumab/hyaluronidase and intravenous trastuzumab based on co-primary endpoints of pathologic complete response and pharmacokinetics. Pathological complete response (pCR) was observed in 118 participants (45.4%) on the trastuzumab/hyaluronidase arm and in 107 participants (40.7%) receiving intravenous trastuzumab (95% CI for difference in pCR: -4.0; 13.4).
SafeHER was a prospective, two-cohort, non-randomized, multinational, open-label trial assessing the overall safety and tolerability of trastuzumab/hyaluronidase with chemotherapy in 1,864 participants with HER2-positive breast cancer. Participants received a fixed dose of 600 mg trastuzumab/hyaluronidase every 3 weeks for 18 cycles. trastuzumab/hyaluronidase was initiated either sequentially with chemotherapy, concurrently with chemotherapy, or without adjuvant chemotherapy, or in combination with neoadjuvant chemotherapy followed by trastuzumab.
References
Further reading
External links
Antineoplastic drugs
Combination cancer drugs
Drugs developed by Genentech
Drugs developed by Hoffmann-La Roche
Monoclonal antibodies for tumors | Trastuzumab/hyaluronidase | [
"Chemistry"
] | 724 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
64,792,453 | https://en.wikipedia.org/wiki/Myrtecaine | Myrtecaine (Nopoxamine), sold as a combination product with diethylamine salicylate under the trade name Algesal and Algésal Suractivé among others, is a local anaesthetic in the form of a topical cream, or with laurilsulfate in rubefacient preparations. It is used to treat muscle strains, tendinitis or ligament sprains and joint pain. It is a surface anaesthetic, adds to the analgesic and anti-inflammatory actions of diethylamine salicylate by facilitating its penetration. Also myrtecaine has a muscle relaxant effect.
References
Local anesthetics
Diethylamino compounds
Ethers
Ethanolamines | Myrtecaine | [
"Chemistry"
] | 150 | [
"Organic compounds",
"Functional groups",
"Ethers"
] |
64,795,106 | https://en.wikipedia.org/wiki/Mail-in-a-Box | Mail-in-a-Box is a free and open-source program for mail server hosting developed by Joshua Tauberer. The software's goal is to enable any user to turn a cloud system into a mail server in a few hours. The tool enables developers to host mail for multiple users and multiple domain names.
The default configuration provides a spam detection system, monitoring, reporting and backup mechanisms. It can also set up and automatically renew a Let's Encrypt certificate, as well as configuring the detailed DNS configurations needed to ensure that a mail server's IP address is trusted by other servers, and less likely to be blacklisted. Its support for IMAP/SMTP facilitates synchronizing across devices.
First developed in 2013 by Tauberer, the tool is written in Python. The project supports Ubuntu LTS.
It has been recommended by the notable Hackaday and MakeTechEasier.
References
External links
Official website
Latest Release 60.1
Free software programmed in Python
2013 software
Free software culture and documents
Ubuntu | Mail-in-a-Box | [
"Technology"
] | 223 | [
"Computing stubs",
"Software stubs"
] |
64,796,876 | https://en.wikipedia.org/wiki/Pambros%20Salt | Panbros Salt Production Limited is a Ghana-based salt production company known for being the largest salt producer in West Africa. The company was established in 1958 by Gerasimos Panagiotopoulos a Greek national and is located in Mendskrom, Ghana.
Processing
Salt ponds are constructed through dugout facilities using pumps. Seawater channeled through the pipes are directed to salt ponds where the water sits for some time before evaporating. The salt crystals that are formed are then collected, treated, processed, bagged and sold to the Ghanaian market and other West African countries.
References
External links
Panbros_Salt
Companies of Ghana | Pambros Salt | [
"Chemistry"
] | 131 | [
"Salt production",
"Salts"
] |
64,796,878 | https://en.wikipedia.org/wiki/Podosphaera%20filipendulae | Podosphaera filipendulae is a fungal species that belongs to the genus Podosphaera and the order Erysiphaceae. It was first described with meadowsweet (Filipendula ulmaria) as the host plant.
Podosphaera filipendulae is morphologically identical to Podosphaera spiraeae and was considered synonymous. However, DNA sequencing can distinguish between isolates of the two species so they are currently considered separate species.
This fungus is a pathogen of meadowsweet that causes powdery mildew on the plant's leaves and flower heads and distorts their growth. It can be evident throughout the growth cycle from spring to autumn. It produces chains of oval conidia as well as groups of cleistothecia.
References
Fungal plant pathogens and diseases
Vegetable diseases
filipendulae
Fungi described in 1981
Fungus species | Podosphaera filipendulae | [
"Biology"
] | 185 | [
"Fungi",
"Fungus species"
] |
64,797,434 | https://en.wikipedia.org/wiki/Parameter%20word | In the mathematical study of combinatorics on words, a parameter word is a string over a given alphabet having some number of wildcard characters. The set of strings matching a given parameter word is called a parameter set or combinatorial cube. Parameter words can be composed, to produce smaller subcubes of a given combinatorial cube. They have applications in Ramsey theory and in computer science in the detection of duplicate code.
Definitions and notation
Formally, a word of length , over a given alphabet , is a sequence of characters, some of which may be drawn from and the others of which are distinct wildcard characters . Each wildcard character is required to appear at least once, but may appear multiple times, and the wildcard characters must appear in the order given by their indexes: the first wildcard character in the word must be , the next one that is different from must be , etc. As a special case, a word over the given
alphabet, without any wildcard characters, is said to be a 0-parameter word. For 1-parameter words, the subscripts may be omitted, as there is no ambiguity between different wildcard characters. The set of all words over , of length , is
A word represents a set of strings (0-parameter words), obtained by substituting a symbol of for each wildcard character. This set of strings is called a parameter set of combinatorial cube, and is called its dimension. A one-dimensional combinatorial cube may be called a combinatorial line.
In a combinatorial cube, each copy of a particular wildcard character must have the same replacement. A generalization of parameter words allows different copies of the same wildcard character to be replaced by different characters from the alphabet, in a controlled way. If is an alphabet and is a group with an action on , then a parameter word is a word together with an assignment of a group element to each wildcard character in the word. The first occurrence of each wildcard character must be assigned the identity element of the group. Then, the strings represented by a labeled parameter word are obtained by choosing a character of for each wildcard character, and substituting the result of combining that character with the group element labeling each copy of that character. The set of all words over , of length , is
Example
In the game of tic-tac-toe, the cells of the game board can be given two integer coordinates from the alphabet . Concatenating these two coordinates produces a string representing each cell, one of the nine strings or . There are seven one-parameter words of length two over this alphabet, the words and . The corresponding combinatorial lines form seven of the eight lines of three cells in a row of the tic-tac-toe board; for instance, the one-parameter word corresponds to the combinatorial line , and the one-parameter word corresponds to the combinatorial
However, one of the eight winning lines of the tic-tac-toe game is missing from this set of combinatorial lines: the antidiagonal It is possible to obtain this line as a combinatorial line (without including any other combinations of cells that would be invalid for tic-tac-toe) by using a group with two elements, and an action in which the non-identity element swaps the alphabet letters and while leaving the element in place. There are eight labeled one-parameter words of length two for this action, seven of which are obtained from the unlabeled one-parameter words by using the identity label for all wildcards. These seven have the same combinatorial lines as before. The eighth labeled word consists of the word labeled by the identity element for its first and the reversing non-identity element for the second ; its combinatorial line is the final winning line of the tic-tac-toe board,
Composition
For three given integer parameters , it is possible to combine two parameter words, and , to produce another parameter word . To do so, simply replace each copy of the th wildcard symbol in by the th character in . This will necessarily produce a word of length that uses each of the wildcard symbols in at least once, in ascending order, so it produces a valid word of length . This notion of composition can also be extended to composition of labeled parameter words (both using the same alphabet and group action), by applying the group action to the non-wildcard substituted characters and composing the group labels for the wildcard substituted characters. A subset of a combinatorial cube is a smaller combinatorial cube if it can be obtained by a composition in this way.
Combinatorial enumeration
The number of parameter words in for an alphabet of size is an -Stirling number of the second kind . These numbers count the number of partitions of the integers in the range into non-empty subsets such that the first integers belong to distinct subsets. Partitions of this type can be placed into a bijective equivalence with the parameter words, by creating a word with a character for each of the integers in the range ,
setting this character value to be either an integer in belonging to the same subset of the partition, or a wildcard character for each subset of the partition that does not contain an integer in . The -Stirling numbers obey a simple recurrence relation by which they may easily be calculated.
Applications
In Ramsey theory, parameter words and combinatorial cubes may be used to formulate the Graham–Rothschild theorem, according to which, for every finite alphabet and group action, and every combination of integer values , , and , there exists a sufficiently large number such that if each combinatorial cube over strings of length is assigned one of colors, then there exists a combinatorial cube all of whose subcubes have the same color. This result is a key foundation for structural Ramsey theory, and is used to define Graham's number, an enormous number used to estimate the value of for a certain combination of values.
In computer science, in the problem of searching for duplicate code,
the source code for a given routine or module may be transformed into a parameter word by converting it into a sequence of tokens,
and for each variable or subroutine name, replacing each copy of the same name with the same wildcard character. If code is duplicated, the resulting parameter words will remain equal even if some of the variables or subroutines have been renamed. More sophisticated searching algorithms can find long duplicate code sections that form substrings of larger source code repositories, by allowing the wildcard characters to be substituted for each other.
An important special case of parameter words, well-studied in the combinatorics of words, is given by the partial words. These are strings with wildcard characters that may be substituted independently of each other, without requiring that some of the substituted characters be equal or controlled by a group action. In the language of parameter words, a partial word may be described as a parameter word in which each wildcard symbol appears exactly once. However, because there is no repetition of wildcard symbols, partial words may be written more simply by omitting the subscripts on the wildcard symbols.
See also
Regular expression
References
Combinatorics on words | Parameter word | [
"Mathematics"
] | 1,489 | [
"Combinatorics on words",
"Combinatorics"
] |
64,797,978 | https://en.wikipedia.org/wiki/List%20of%20carburetor%20manufacturers | A carburetor (American English) or carburettor (British English) is a device that mixes air and fuel for internal combustion engines in a suitable air–fuel ratio for combustion.
List
AMAL, producer of carburetors and hand controls for British motorcycles and light industrial engines.
Autolite, a division of the Ford Motor Company from 1967 to 1973, and from 1974 to 1985 manufactured by Motorcraft (also a division of Ford Motor Company).
Bendix Stromberg and Bendix Technico carburetors were used on aircraft and used on vehicles manufactured by Chrysler, International Harvester, Ford, GM, AMC, and Studebaker.
Bing, Germany (Fritz Hintermayr GmbH Bing-Vergaser-Fabrik).
Carter, used on numerous makes of vehicles, including those made by Chrysler, IHC, Ford, GM, AMC, and Studebaker, as well as on industrial and agricultural equipment and small engines.
Claudel-Hobson, UK.
Dell'Orto carburetors from Italy, used on cars and motorcycles.
Edelbrock performance carburetors.
Hitachi, found on Japanese vehicles.
Holley, with usage as broad as Carter and Weber.
Jikov, Czechoslovak, used in Škoda cars.
Keihin, a keiretsu group company affiliated with Honda.
Mikuni, common on Japanese motorcycles, especially in the 1980s. Mikuni also made racing carburetors for Japanese, British and European cars. Original equipment on Mitsubishi engines.
Reece Fish, in Volkswagen, Austin Mini, Morris Mini.
Rochester Products, a General Motors subsidiary; also sold Weber/Magneti Marelli carburetors under license).
Solex – French carburetors, owned by Weber.
Société du carburateur Zénith, commonly found in French-designed vehicles; used both in automobiles and aviation.
SU Carburettors, widely used on British Commonwealth and European-designed vehicles.
Villiers, used on UK motorcycles and small engines.
Walbro and Tillotson carburetors for small engines.
Weber carburetor, Italian, now made in Spain, owned by Magneti Marelli.
Wheeler–Schebler Carburetor Company.
Zama Group, primarily an OEM provider.
Zenith Carburetor Company, American subsidiary of Société du carburateur Zénith.
Zenith Carburettor Company (British), used on Austin cars. Also produced the Zenith-Stromberg carburetors. Subsidiary of Société du carburateur Zénith.
References
Carburetor
Engine fuel system technology
Engine components | List of carburetor manufacturers | [
"Technology"
] | 539 | [
"Engine components",
"Engines"
] |
64,798,424 | https://en.wikipedia.org/wiki/Harmony%20%28operating%20system%29 | Harmony is an experimental computer operating system (OS) developed at the National Research Council Canada in Ottawa. It is a second-generation message passing system that was also used as the basis for several research projects, including robotics sensing and graphical workstation development. Harmony was actively developed throughout the 1980s and into the mid-1990s.
History
Harmony was a successor to the Thoth system developed at the University of Waterloo. Work on Harmony began at roughly the same time as that on the Verex kernel developed at the University of British Columbia. David Cheriton was involved in both Thoth and Verex, and would later go on to develop the V System at Stanford University. Harmony's principal developers included W. Morven Gentleman, Stephen A. MacKay, Darlene A. Stewart, and Marceli Wein.
Early ports of the system existed for a variety of Motorola 68000-based computers, including ones using the VMEbus and Multibus backplanes and in particular the Multibus-based Chorus multiprocessor system at Waterloo. Other hosts included the Atari 520 or 1040 ST. A port also existed for the Digital Equipment Corporation VAX.
Harmony achieved formal verification in 1995.
Features
Harmony was designed as a real-time operating system (RTOS) for robot control. It is a multitasking, multiprocessing system. It is not multi-user. Harmony provided a runtime system (environment) only; development took place on a separate system, originally an Apple Macintosh. For each processor in the system, an image is created that combines Harmony with the one multitask program for that processor at link time, an exception being a case where the kernel is programmed into a read-only memory (ROM).
Although the term did not appear in the original papers, Harmony was later referred to as a microkernel. A key in Harmony is its use of the term task, which in Harmony is defined as the "unit of sequential and synchronous execution" and "the unit of resource ownership". It is likened to a subroutine, but one that must be explicitly created and which runs independently of the task that created it. Programs are made up of a number of tasks. A task is bound to a specific processor, which may be different from that of the instantiating task and which may host many tasks. All system resources are owned and managed by tasks.
Intertask communication is provided mostly by synchronous message passing and four associated primitives. Shared memory is also supported. Destruction of a task closes all of its connections. Input/output uses a data stream model.
Harmony is connection-oriented in that tasks that communicate with each other often maintain state information about each other. In contrast with some other distributed systems, connections in Harmony are inexpensive.
Applications and tools
An advanced debugger called Melody was developed for Harmony at the Advanced Real-Time Toolset Laboratory at Carleton University. It was later commercialized as Remedy.
The Harmony kernel underpinned the Actra project — a multiprocessing, multitasking Smalltalk.
Harmony was used in the multitasking, multiprocessor Adagio robotics simulation workstation.
Concepts from both Harmony and Adagio influenced the design of the Smalltalk-based Eva event driven user interface builder.
Harmony was used as the underlying OS for several experimental robotic systems.
Commercial
Harmony was commercialized by the Taurus Computer Products division of Canadian industrial computer company Dy4. When Dy4 closed down their software division, four of Taurus' former developers founded Precise Software Technologies and continued developing the OS as Precise/MPX, the predecessor to their later Precise/MQX product.
Another commercial operating system derived from Harmony is the Unison OS from Rowebot Research Inc.
References
Further reading
Real-time operating systems
National Research Council (Canada)
Microkernel-based operating systems
Robot operating systems
Operating system families | Harmony (operating system) | [
"Technology"
] | 791 | [
"Real-time computing",
"Real-time operating systems"
] |
64,799,250 | https://en.wikipedia.org/wiki/Algorithmic%20Combinatorics%20on%20Partial%20Words | Algorithmic Combinatorics on Partial Words is a book in the area of combinatorics on words, and more specifically on partial words. It was written by Francine Blanchet-Sadri, and published in 2008 by Chapman & Hall/CRC in their Discrete Mathematics and its Applications book series.
Topics
A partial word is a string whose characters may either belong to a given alphabet or be a wildcard character. Such a word can represent a set of strings over the alphabet without wildcards, by allowing each wildcard character to be replaced by any single character of the alphabet, independently of the replacements of the other wildcard characters. Two partial words are compatible when they agree on their non-wildcard characters, or equivalently when there is a string that they both match; one partial word contains another partial word if they are compatible and the non-wildcard positions of contain those of ; equivalently, the strings matched by are a subset of those matched by .
The book has 12 chapters, which can be grouped into five larger parts. The first part consists of two introductory chapters defining partial words, compatibility and containment, and related concepts. The second part generalizes to partial words some standard results on repetitions in strings, and the third part studies the problem of characterizing and recognizing primitive partial words, the partial words that have no repetition. Part four concerns codes defined from sets of partial words, in the sense that no two distinct concatenations of partial words from the set can be compatible with each other. A final part includes three chapters on advanced topics including the construction of repetitions of given numbers of copies of partial words that are compatible with each other, enumeration of the possible patterns of repetitions of partial words, and sets of partial words with the property that every infinite string contains a substring matching the set. Each chapter includes a set of exercises, and the end of the book provides hints to some of these exercises.
Audience and reception
Although Algorithmic Combinatorics on Partial Words is primarily aimed at the graduate level, reviewer Miklós Bóna writes that it is for the most part "remarkably easy to read" and suggests that it could also be read by advanced undergraduates. However, Bóna criticizes the book as being too focused on the combinatorics on words as an end in itself, with no discussion of how to translate mathematical structures of other types into partial words so that the methods of this book can be applied to them. Because of this lack of generality and application, he suggests that the audience for the book is likely to consist only of other researchers specializing in this area. Similarly, although Patrice Séébold notes that this area can be motivated by applications to gene comparison, he criticizes the book as being largely a catalog of its author's own research results in partial words, without the broader thematic overview or identification of the fundamental topics and theorems that one would expect of a textbook, and suggests that a textbook that accomplishes these goals is still waiting to be written.
However, reviewer Jan Kratochvíl is more positive, calling this "the first reference book on the theory of partial words", praising its pacing from introductory material to more advanced topics, and writing that it well supports its underlying thesis that many of the main results in the combinatorics of words without wildcards can be extended to partial words. He summarizes it as "an excellent textbook as well as a reference book for interested researchers".
References
Combinatorics on words
Mathematics books
2008 non-fiction books | Algorithmic Combinatorics on Partial Words | [
"Mathematics"
] | 716 | [
"Combinatorics on words",
"Combinatorics"
] |
64,799,736 | https://en.wikipedia.org/wiki/Wendy%20Lee%20Queen | Wendy Lee Queen (born 1981 in South Carolina) is an American chemist and material scientist. Her research interest focus on development design and production of hybrid organic/inorganic materials at the intersection of chemistry, chemical engineering and material sciences. As of 2020 she is a tenure-track assistant professor at the École polytechnique fédérale de Lausanne (EPFL) in Switzerland, where she directs the Laboratory for Functional Inorganic Materials.
Career
Queen studied chemistry and mathematics at Lander University in Greenwood, South Carolina, USA. She then pursued a PhD in inorganic chemistry at Clemson University under the mentorship of Shiou-Jyh Hwu. In 2009 she joined the Center for Neutron Research at National Institute of Standards and Technology. From 2011 to 2012 she was a visiting scholar in laboratory of Jeffrey R. Long at University of California Berkeley before returning to the Center for Neutron Research as a postdoctoral fellow with Craig Brown.
In the position of a project scientist, Queen joined the Molecular Foundry at Lawrence Berkeley National Laboratory in 2012. Here she helped build a new user program focused on the synthesis and characterization of porous adsorbents. During her time there she worked on a number of projects focused on the use of polymer-metal-organic frameworks (MOF) or MOF-based membranes for a variety of globally relevant gas separations such as carbon dioxide capture from flue gas and water capture from air.
In 2015, she was nominated as tenure-track assistant professor at Department of Chemical Engineering of École polytechnique fédérale de Lausanne (EPFL) in Switzerland. Her Laboratory for Functional Inorganic Materials is based at the EPFL Valais Wallis campus in Sion, Switzerland.
Research
Queen's research is focused on the synthesis and characterization of novel porous adsorbents, namely metal-organic frameworks, and their corresponding composites, which are of interest in a number of host-guest applications. Her research aims at contributing knowledge towards solving globally relevant problems, like reducing energy consumption, cutting CO2 emissions, water purification, the extraction of valuable commodities from waste, and chemical conversion processes.
Queen became known to a wider audience through her TEDx Talk on "Cut Carbon to Save Lives", her Aeon article on "Could mining gold from waste reduce its great cost?", and multiple appearances in the news outlets.
Distinctions
In 2020, Queen was nominated as one of Chemical & Engineering News's “Talented 12”. She is a member of the board of Scientific Advisors at novoMOF.
References
External links
American women chemists
Women materials scientists and engineers
Academic staff of the École Polytechnique Fédérale de Lausanne
21st-century American women scientists
21st-century American chemists
American expatriate academics
American expatriates in Switzerland
American materials scientists
Lander University alumni
1981 births
Living people
Clemson University alumni
American women academics
Scientists from South Carolina
Chemists from South Carolina | Wendy Lee Queen | [
"Materials_science",
"Technology"
] | 583 | [
"Women materials scientists and engineers",
"Materials scientists and engineers",
"Women in science and technology"
] |
64,799,753 | https://en.wikipedia.org/wiki/Mackey%E2%80%93Glass%20equations | In mathematics and mathematical biology, the Mackey–Glass equations, named after Michael Mackey and Leon Glass, refer to a family of delay differential equations whose behaviour manages to mimic both healthy and pathological behaviour in certain biological contexts, controlled by the equation's parameters. Originally, they were used to model the variation in the relative quantity of mature cells in the blood. The equations are defined as:
and
where represents the density of cells over time, and are parameters of the equations.
Equation (), in particular, is notable in dynamical systems since it can result in chaotic attractors with various dimensions.
Introduction
There exist an enormous number of physiological systems that involve or rely on the periodic behaviour of certain subcomponents of the system. For example, many homeostatic processes rely on negative feedback to control the concentration of substances in the blood; breathing, for instance, is promoted by the detection, by the brain, of high CO2 concentration in the blood. One way to model such systems mathematically is with the following simple ordinary differential equation:
where is the rate at which a "substance" is produced, and controls how the current level of the substance discourages the continuation of its production. The solutions of this equation can be found via an integrating factor, and have the form:
where is any initial condition for the initial value problem.
However, the above model assumes that variations in the substance concentration is detected immediately, which often not the case in physiological systems. In order to ease this problem, proposed changing the production rate to a function of the concentration at an earlier point in time, in hope that this would better reflect the fact that there is a significant delay before the bone marrow produces and releases mature cells in the blood, after detecting low cell concentration in the blood. By taking the production rate as being:
we obtain Equations () and (), respectively. The values used by were , and , with initial condition . The value of is not relevant for the purpose of analyzing the dynamics of Equation (), since the change of variable reduces the equation to:
This is why, in this context, plots often place in the -axis.
Dynamical behaviour
It is of interest to study the behaviour of the equation solutions when is varied, since it represents the time taken by the physiological system to react to the concentration variation of a substance. An increase in this delay can be caused by a pathology, which in turn can result in chaotic solutions for the Mackey–Glass equations, especially Equation (). When , we obtain a very regular periodic solution, which can be seen as characterizing "healthy" behaviour; on the other hand, when the solution gets much more erratic.
The Mackey–Glass attractor can be visualized by plotting the pairs . This is somewhat justified because delay differential equations can (sometimes) be reduced to a system of ordinary differential equations, and also because they are approximately infinite dimensional maps.
See also
Circadian rhythm
Circadian oscillator
Neural oscillation
References
Chaotic maps | Mackey–Glass equations | [
"Mathematics"
] | 608 | [
"Functions and mappings",
"Mathematical objects",
"Mathematical relations",
"Chaotic maps",
"Dynamical systems"
] |
69,162,108 | https://en.wikipedia.org/wiki/Bromine%20nitrate | Bromine mononitrate is an inorganic compound, derived from bromine and nitric acid with the chemical formula BrNO3. The compound is a yellow liquid, decomposes at temperatures above 0 °C.
This compounds is extremely reactive due to its intrinsic instability, which makes handling and synthesis challenging. Because of its explosive potential and corrosive character, this substance is mostly used for study in restricted laboratory settings. About its particular characteristics and uses outside of its use as a chemical research subject, not much is known.
Synthesis
Bromine nitrate can be prepared by several methods:
1. Reaction of silver nitrate on an alcoholic solution of bromine:
2. Reaction of bromine chloride with chlorine nitrate at low temperatures:
Physical properties
Bromine mononitrate forms an unstable yellow liquid that decomposes at temperatures above 0 °C.
The molecule has the structure BrONO2.
The compound is easily soluble in trichlorofluoromethane and carbon tetrachloride.
Applications
Bromine nitrate plays a role in tropospheric chemistry as it reacts with sulfuric acid.
References
Bromine(I) compounds
Nitrates | Bromine nitrate | [
"Chemistry"
] | 232 | [
"Nitrates",
"Oxidizing agents",
"Salts"
] |
69,162,765 | https://en.wikipedia.org/wiki/Glycomacropeptide | Glycomacropeptide (GMP) is a glycosylated peptide formed during renneting as a fragment of sweet whey. Acid whey from yogurt or curdling cheese without the use of rennet does not contain GMP. The unglycosylated form is known as caseinomacropeptide or CMP. Both forms exist in roughly similar amounts in whey.
Together GMP and CMP make up 20-25% of whey protein. This makes them the third largest fraction of whey protein isolate, after alpha-lactalbumin and beta-lactoglobulin. GMP is formed when the casein micelle that encapsulates milk protein is cleaved by the enzyme chymosin. The 64 terminal peptides of Kappa-casein are removed by the enzyme to create GMP. The remaining peptides form para-kappa-casein. Vegetable rennets cleave at the same location and thus also produce GMP.
Properties
GMP is unique from other milk peptides in several ways. Kappa-casein is the only glycosylated casein protein and GMP, which makes up much of Kappa-casein, is also glycosylated. The glycans make GMP the only portion of the casein micelle that is water soluble after curdling has occurred, and thus, the only fraction of casein protein to dissolve into the whey.
Additionally, GMP is the only easily attainable source of dietary peptides that does not contain any aromatic amino acids. This makes it a safe source for individuals with phenylketonuria to obtain dietary amino acids, as phenylalanine is an aromatic amino acid.
References
Peptides | Glycomacropeptide | [
"Chemistry"
] | 368 | [
"Biomolecules by chemical classification",
"Peptides",
"Molecular biology"
] |
69,164,293 | https://en.wikipedia.org/wiki/Compliance%20constants | Compliance constants are the elements of an inverted Hessian matrix. The calculation of compliance constants provides an alternative description of chemical bonds in comparison with the widely used force constants explicitly ruling out the dependency on the coordinate system. They provide the unique description of the mechanical strength for covalent and non-covalent bonding. While force constants (as energy second derivatives) are usually given in aJ/Å or N/cm, compliance constants are given in Å/aJ or Å / mdyn.
History
Hitherto, recent publications that broke the wall of putative chemical understanding and presented detection/isolation of novel compounds with intriguing bonding characters can still be provocative at times. The stir in such discoveries arose partly from the lack of a universally accepted bond descriptor. While bond dissociation energies (BDE) and rigid force constants have been generally regarded as primary tools for such interpretation, they are prone to flawed definition of chemical bonds in certain scenarios whether simple or controversial.
Such reasons prompted the necessity to seek an alternative approach to describe covalent and non-covalent interactions more rigorously. , a German chemist at the TU Braunschweig and his Ph.D. student at the time, Kai Brandhorst, developed a program COMPLIANCE (freely available to the public), which harnesses compliance constants for tackling the aforementioned tasks. The authors use an inverted matrix of force constants, i.e., inverted Hessian matrix, originally introduced by W. T. Taylor and K. S. Pitzer. The insight in choosing the inverted matrix is from the realization that not all elements in the Hessian matrix are necessary—and thus redundant—for describing covalent and non-covalent interactions. Such redundancy is common for many molecules, and more importantly, it ushers in the dependence of the elements of the Hessian matrix on the choice of coordinate system. Therefore, the author claimed that force constants albeit more widely used are not an appropriate bond descriptor whereas non-redundant and coordinate system-independent compliance constants are.
Theory
Force constants
By Taylor series expansion, the potential energy, , of any molecule can be expressed as:
(eq. 1)
where is a column vector of arbitrary and fully determined displacement coordinates, and and are the corresponding gradient (first derivative of ) and Hessian (second derivative of ), respectively. The point of interest is the stationary point on a potential energy surface (PES), so is treated as zero, and by considering the relative energy, as well becomes zero. By assuming harmonic potential and regarding the third derivative term and forth as negligible, the potential energy formula then simply becomes:
(eq. 2)
Transitioning from cartesian coordinates to internal coordinates , which are more commonly used for the description of molecular geometries, gives rise to equation 3:
(eq. 3)
where is the corresponding Hessian for internal coordinates (commonly referred to as force constants), and it is in principle determined by the frequencies of a sufficient set of isotopic molecules. Since the Hessian is the second derivative of the energy with respect to displacements and that is the same as the first derivative of the force, evaluation of this property as shown in equation 4 is often used to describe chemical bonds.
(eq. 4)
Nevertheless, there are several issues with this method as explained by Grunenberg, including the dependence of force constants on the choice of internal coordinates and the presence of the redundant Hessian which has no physical meaning and consequently engenders ill-defined description of bond strength.
Compliance constants
Rather than internal displacement coordinates, an alternative approach to write the potential energy of a molecule as explained by Decius is to write it as a quadratic form in terms of generalized displacement forces (negative gradient) .
(eq. 5)
This gradient is the first derivative of the potential energy with respect to the displacement coordinates, which can be expressed as shown:
(eq. 6)
By substituting the expression of in eq. 5 into equation 5, equation 7 is obtained.
(eq. 7)
Thus, with the knowledge that is positive definite, the only possible value of which is the compliance matrix then must be:
(eq. 8)
Equation 7 offers a surrogate formulation of the potential energy which proves to be significantly advantageous in defining chemical bonds. Specially, this method is independent on coordinate selection and also eliminates such issue with redundant Hessian that the common force constant calculation method suffers with. Intriguingly, compliance constants calculation can be employed regardless of the redundancy of the coordinates.
Archetype of compliance constants calculation
Cyclobutane: force constants calculations
To illustrate how choices of coordinate systems for calculations of chemical bonds can immensely affect the results and consequently engender ill-defined descriptors of the bonds, sample calculations for n-butane and cyclobutane are shown in this section. Note that it is known that the all the four equivalent C-C bonds in cyclobutane are weaker than any of the two distinct C-C bonds in n-butane; therefore, juxtaposition and evaluation of the strength of the C-C bonds in this C4 system can exemplify how force constants fail and how compliance constants do not. The tables immediately below are results that are calculated at MP2/aug-cc-pvtz level of theory based on typical force constants calculation.
Tables 1 and 2 display a force constant in N/cm between each pair of carbon atoms (diagonal) as well as the coupling (off-diagonal). Considering natural internal coordinates on the left, the results make chemical sense. Firstly, the C-C bonds are n-butane are generally stronger than those in cyclobutane, which is in line with what is expected. Secondly, the C-C bonds in cyclobutane are equivalent with the force constant values of 4.173 N/cm. Lastly, there is little coupling between the force constants as seen as the small compliance coupling constants in the off-diagonal terms.
However, when z-matrix coordinates are used, the results are different from those obtained from natural internal coordinates and become erroneous. The four C-C bonds all have distinct values in cyclobutane, and the coupling becomes much more pronounced. Significantly, the force constants of the C-C bonds in cyclobutane here are also larger than those of n-butane, which is in conflict with chemical intuition. Clearly for cyclobutane—and numerous other molecules, using force constants therefore gives rise to inaccurate bond descriptors due to its dependence on coordinate systems.
Cyclobutane: compliance constants calculations
A more accurate approach as claimed by Grunenberg is to exploit compliance constants as means for describing chemical bonds as shown below.
All the calculated compliance constants above are given in N−1 unit. For both n-butane and cyclobutane, the results are the same regardless of the choice of the coordinate systems. One aspect of compliance constants that proves more powerful than force constants in cyclobutane is because of less coupling. This compliance coupling constants are the off-diagonal elements in the inverted Hessian matrix and altogether with the compliance constants, they physically describe the relaxed distortion of a molecule closely through a minimum energy path. Moreover, the values of the compliance constants yield the same results for all the C-C bonds and the values are less compared to those obtained for n-butane. Compliance constants, thus, give results that are in accordance to what are generally known about the ring strain of cyclobutane.
Applications to main group compounds
Diboryne
Diboryne or a compound with boron-boron triple bond was first isolated as a N-heterocyclic carbene supported complex (NHC-BB-NHC) in the Braunschweig group, and its unique, peculiar bonding structure thereupon catalyzed new research to computationally assess the nature of this at that time controversial triple bond.
A few years later, Köppe and Schnöckel published an article arguing that the B-B bond should be defined as a 1.5 bond based on thermodynamic view and rigid force constant calculations. That same year, Grunenberg reassessed the B-B bond using generalized compliance constants of which he claimed better suited as a bond strength descriptor.
The calculated relaxed force constants show a clear trend as the bond order between the B-B bond increases, which advocates the existence of the triple bond in Braunschweig's compound.
Digallium bonds
Grunenberg and N. Goldberg probed the bond strength of a Ga-Ga triple bond by calculating the compliance constants of digallium complexes with a single bond, a double bond, or a triple bond. The results show that the Ga-Ga triple bond of a model Na[H-GaGa-H] compound in C symmetry has a compliance constant value of 0.870 aJ/Å is in fact weaker than a Ga-Ga double bond (1.201 aJ/Å).
Watson-Crick base pairs
Besides chemical bonds, compliance constants are also useful for determining non-covalent bonds, such as H-bonds in Watson-Crick base pairs. Grunenberg calculated the compliance constant for each of the donor-H⋯acceptor linkages in AT and CG base pairs and found that the central N-H⋯N bond in CG base pair is the strongest one with the compliance constant value of 2.284 Å / mdyn. (Note that the unit is reported in a reverse unit.) In addition, one of the three hydrogen bonding interactions in a AT base pair shows an extremely large compliance value of >20 Å / mdyn indicative of a weak interaction.
References
Chemical bonding
Intermolecular forces
Chemistry | Compliance constants | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 2,037 | [
"Molecular physics",
"Materials science",
"Intermolecular forces",
"Condensed matter physics",
"nan",
"Chemical bonding"
] |
69,164,461 | https://en.wikipedia.org/wiki/Tauc%E2%80%93Lorentz%20model | The Tauc–Lorentz model is a mathematical formula for the frequency dependence of the complex-valued relative permittivity, sometimes referred to as the dielectric function. The model has been used to fit the complex refractive index of amorphous semiconductor materials at frequencies greater than their optical band gap. The dispersion relation bears the names of Jan Tauc and Hendrik Lorentz, whose previous works were combined by G. E. Jellison and F. A. Modine to create the model. The model was inspired, in part, by shortcomings of the Forouhi–Bloomer model, which is aphysical due to its incorrect asymptotic behavior and non-Hermitian character. Despite the inspiration, the Tauc–Lorentz model is itself aphysical due to being non-Hermitian and non-analytic in the upper half-plane.
Further researchers have modified the model to address these shortcomings.
Mathematical formulation
The general form of the model is given by
where
is the relative permittivity,
is the photon energy (related to the angular frequency by ),
is the value of the relative permittivity at infinite energy,
is related to the electric susceptibility.
The imaginary component of is formed as the product of the imaginary component of the Lorentz oscillator model and a model developed by Jan Tauc for the imaginary component of the relative permittivity near the bandgap of a material. The real component of is obtained via the Kramers-Kronig transform of its imaginary component. Mathematically, they are given by
where
is a fitting parameter related to the strength of the Lorentzian oscillator,
is a fitting parameter related to the broadening of the Lorentzian oscillator,
is a fitting parameter related to the resonant frequency of the Lorentzian oscillator,
is a fitting parameter related to the bandgap of the material.
Computing the Kramers-Kronig transform,
where
,
,
,
,
.
See also
Cauchy equation
Sellmeier equation
Lorentz oscillator model
Forouhi–Bloomer model
Brendel–Bormann oscillator model
References
Condensed matter physics
Electric and magnetic fields in matter
Optics | Tauc–Lorentz model | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 466 | [
"Applied and interdisciplinary physics",
"Optics",
"Phases of matter",
"Electric and magnetic fields in matter",
"Materials science",
"Condensed matter physics",
" molecular",
"Atomic",
"Matter",
" and optical physics"
] |
69,164,645 | https://en.wikipedia.org/wiki/Polysaccharide%E2%80%93protein%20conjugate | Polysaccharide–protein conjugates may have better solubility and stability, reduced immunogenicity, prolonged circulation time, and enhanced targeting ability compared to native protein. They are promising alternatives to PEG–protein drugs, in which non-biodegradable high molecular weight PEG causes health concerns.
Synthetic methods
Reductive amination, the Maillard reaction, EDC/NHS coupling, DMTMM coupling, disulfide bond formation, and click chemistry are common methods to synthesize polysaccharide–protein conjugates.
Applications
Polysaccharide–protein conjugates are used for food industry, vaccines, and drug delivery systems.
References
Protein complexes
Polysaccharides | Polysaccharide–protein conjugate | [
"Chemistry"
] | 152 | [
"Biochemistry stubs",
"Carbohydrates",
"Protein stubs",
"Polysaccharides"
] |
69,164,925 | https://en.wikipedia.org/wiki/Tetraoxygen%20difluoride | Tetraoxygen difluoride is an inorganic chemical compound of oxygen, belonging to the family of oxygen fluorides. It consists of two O2F units bound together with a weak O-O bond, and is the dimer of the O2F radical.
Preparation
Tetraoxygen difluoride can be prepared in two steps. In the first step, a photochemically generated fluorine atom reacts with oxygen to form the dioxygen fluoride radical.
This radical subsequently undergoes dimerization, entering an equilibrium with tetraoxygen difluoride at temperatures under −175 °C:
At the same time, the dioxygen fluoride radicals decompose into dioxygen difluoride and oxygen gas, which shifts the above equilibrium with O4F2 to the left.
Properties
Tetraoxygen difluoride is dark red-brown as a solid and has a melting point around −191 °C.
It is a strong fluorinating and oxidizing agent, even stronger than dioxygen difluoride, so that it can, for example, oxidize Ag(II) to Ag(III) or Au(III) to Au(V). This process creates the corresponding anions AgF and AuF. With non-noble substances this oxidation can lead to explosions even at low temperatures. As an example, elemental sulfur reacts explosively to form sulfur hexafluoride even at −180 °C.
Similar to [O2F]• or O2F2, tetraoxygen difluoride tends to form salts with the dioxygenyl cation O when it reacts with fluoride acceptors such as boron trifluoride (BF3). In the case of BF3, this leads to the formation of O2+•BF4−:
O4F2 + 2BF3 -> 2O2+BF4−
Similarly, for arsenic pentafluoride it reacts to create O2+AsF6−.
References
Oxygen fluorides
Peroxides | Tetraoxygen difluoride | [
"Chemistry"
] | 440 | [
"Oxygen fluorides",
"Oxidizing agents"
] |
69,164,997 | https://en.wikipedia.org/wiki/HD%20283572 | HD 283572 is a young T Tauri-type pre-main sequence star in the constellation of Taurus about away, belonging to the Taurus Molecular Cloud. It is a rather evolved protostar which already dispersed its birth shroud. The star emits a very high X-ray flux of 1031 ergs/s. That radiation flux associated with the magnetic activity induced a high coronal temperature of 3 kEv and regular flares. HD 283572 will eventually evolve to an A-type main-sequence star when on the main sequence. It is no longer accreting mass, and is magnetically decoupled from the remnants of the protoplanetary disk, belonging to the terminal, 3rd phase of the disk evolution.
Submillimeter Array (SMA) 1.3mm observations of HD 283572 detected an extreme brightening event with a radio luminosity of 8.3x1016erg/s/Hz that spanned 9 hours on January 17th 2022.
Although HD 283572 was observed by the SMA on 8 separate nights, millimeter emission was detected on one night only, strongly suggesting stellar variability as a result of an extreme stellar flare.
Protoplanetary system
HD 283572 is surrounded by a light (<0.0004 ) and faint protoplanetary disk with uncertain inclination. Different instruments yielded measurements of disk inclination to the plane of sky from 35 to 60 degrees. A search for planetary transits was performed but no planets were detected as of 2019.
References
T Tauri stars
Circumstellar disks
Taurus (constellation)
J04215884+2818066
Tauri, V987
BD+27 657
020388
283572 | HD 283572 | [
"Astronomy"
] | 357 | [
"Taurus (constellation)",
"Constellations"
] |
69,166,746 | https://en.wikipedia.org/wiki/TPC-C | TPC-C, short for Transaction Processing Performance Council Benchmark C, is a benchmark used to compare the performance of online transaction processing (OLTP) systems. This industry standard was published in August 1992, and eventually replaced the earlier TPC-A, which was declared obsolete in 1995. It has undergone a number of changes to keep it relevant as computer performance grew by several orders of magnitude, with the current version , 5.11, released in 2010. In 2006, a newer OLTP benchmark was added to the suite, TPC-E, but TPC-C remains in widespread use.
The TPC-C system models a multi-warehouse wholesale operation, known simply as "the Company". In a minimal test, the company has ten warehouses, each with ten user terminals. Each warehouse serves ten defined sales districts, each with 3,000 customers who are ordering against a product catalog of 100,000 items. The most frequent transactions are customer orders, with an average of ten items on each order, and customer payments. Less frequent requests query the status of orders and warehouse inventory, ship orders and replenish stocks that get low. To test the performance of a given system, the number of warehouses is increased to meet the required minimum needed to measure the targeted performance level.
The results of the benchmark are measured in transactions per minute, known as tpmC. The first tpmC result was published in September 1992 for an IBM AS/400 and returned a result of 54 tpmC. By the 2000s, the average result for high-end machines was 2.4 million tpmC, and companies were building systems of very large size in an effort to capture the record. The current record was set in 2020 using cloud computing that provided 707.3 million tpmC. Recent results for smaller on-premises systems have focused on lowering the cost-per-tpmC.
IBM modified TPC-C to create a simplified version known as the Commercial Processing Workload for their own internal use. Similar conversions are commonplace but generally not known outside the respective companies.
History
Prior work
The release of relational databases like Oracle led to debates within the industry between the relational model and the older CODASYL concepts. Out of these debates grew a desire to offer realistic performance estimates. In 1985, Jim Gray of Tandem Computers co-authored a paper now known as "Anon et.al.", which outlined a potential standard named DebitCredit.
This quickly saw many modifications and apples-to-oranges comparison, which, in turn, led to a June 1988 effort by Tom Sawyer and Omri Serlin to standardize the system and publish a new version. The publication of this version and ongoing controversy over its use led to the August 1988 creation of an industry consortium named the Transaction Processing Performance Council, or TPC, to take over such work and create a formal industry standard.
The TPC produced its first industry standard benchmark, named TPC-A, on the basis of DebitCredit with the addition of full ACID properties. Other requirements were primarily organizational; to submit a result one now had to provide complete details of the system and testing, with 3rd party audits suggested, and any pricing information had to include maintenance contracts over a period of five years. A related benchmark was released shortly after and named TPC-B, which differed primarily in that it used batch inputs rather than emulating terminal input.
Order-Entry
Around the time that TPC-A was being finalized, Digital Equipment Corporation (DEC) was working on a new distributed database system, RdbStar. This led to the development of a new benchmark to measure the performance of the new database system. The RdbStar performance team surveyed many existing pre-TPC benchmarks like the Wisconsin benchmark, AS3AP, and the Set Query Benchmark. They also examined real-world database use cases from a canvassing of DEC's European division's customers. Ultimately they selected components of an unpublished workload from the Austin-based Microelectronics and Computer Consortium that simulated a warehousing operation. The team used this workload as the basis for their own benchmark, known as Order-Entry.
By the time TPC-B had been published in August 1990, there were already concerns that Debit/Credit was too simple and not really modeling typical workloads. In November a new effort started with a call to industry to provide a new benchmark. IBM responded with their RAMP-C while DEC offered Order-Entry. DEC's proposal was selected, and its primary author, Francois Raab, was selected as technical lead for the standardization effort. This effort lasted eighteen months and culminated in the release of TPC-C version 1.0 on 13 August 1992.
Post-release
The TPC-C benchmark specification underwent several minor revisions over the next few years. Revision 1.1 of June 1993 clarified some of the language and required customer-side pricing of the tested system. 2.0 of October 1993 changed various reporting requirements and added language to exclude any benchmark-specific enhancements. 3.0 of February 1996 added transaction tracking, new fields for the addition of images (ultimately never used), and the removal of the terminals from the total system price, as by this time the cost of the servers had sufficiently declined that the cost of the terminals was becoming too large of a portion of the total price.
The benchmark continued to evolve to accommodate the emergence of new computing architectures like the client-server model and to clarify the rules governing the proper execution of the testing steps and the required reporting. The most significant changes took place in 2000 and consisted in switching the maintenance pricing from five to three years and from five 8-hour days (5x8) to seven 24-hour days (7x24), reducing the measurement duration from eight to two hours and reducing the archival space requirement by a factor of three. These three major changes were released as version 5.0 on 26 February 2001. Minor changes have been made since involving clarification of various requirements spelled out in the benchmark specification. , the latest revision is 5.11, published 11 February 2010.
The first published result from the new benchmark was published in September 1992 at 54 tpmC. Since then, the records for TPC-C increased over time almost exactly according to Moore's Law. Initial results were in the tens, but after a year these stood in the hundreds, and by January 1998 the record stood at 52,871. By 2010 this reached the million range. During the 2000s, the number of records decreased as the cost of breaking the record grew tremendously. Through this period, Microsoft turned their attention to the newer TPC-E benchmark, leaving Oracle to build huge systems and repeatedly set the record that others could not afford to match.
Record attempts after this point were relatively few until the rise of cloud computing in the late 2010s. The current record holder is Ant Financial, whose OceanBase powers Alibaba. In August 2019 they set the record at just over 60 million, the first attempt since Oracle's 8 million result in 2013. Others were quick to point out that Oracle's record was on a single workstation while Ant's required a complete computing farm. To put such complaints to rest, in May 2020 Ant published a new record at 707 million. This record stands to this day.
Description
TPC-C is based on an Order-Entry workload presented to the TPC by DEC. The earlier TPC-A benchmark had focused primarily on database updates matching the operations in a simplistic Debit/Credit bookkeeping system, which did not match real-world usage patterns. A sample of production workloads showed that a more complex mix of inserts interspersed with updates and read-only operations were needed to more adequately represented real world patterns. Moreover, the TPC-A database did not have much complexity; real-world systems spread their data across many more tables of more varied size and complexity.
TPC-C uses a database schema with nine tables in total. The structure is driven primarily by the Warehouse table, which contains a number of warehouse entries denoted W. W has a minimum value of 10, and must be increased to match the saturation level of the tested systems, using W as a scaling factor. The reported performance metric cannot exceed 12.86 x W. Warehouses all maintain a stock of the same catalogue of items. The Item table has 100,000 rows and the Stock table has W x 100,000 rows. A second branch of the schema are the Districts, with 10 entries for each Warehouse. Districts have Customers, 3000 per District. They generate Orders with 5 to 15 Order-Lines per Order. This means Order-Line is the largest table, with about W(arehouses) x 3000 (Customers) x 10 (initial Orders) x 10 (Order Lines) = W x 300,000 entries. The process of filling an order interacts with the Stock entries associated with one or more warehouses.
The activity consists of a series of W x 10 virtual terminals entering transactions according to a semi-random formula; the primary transaction is New-Order which creates a single order. Each order results in one Payment transaction and one Delivery. One Order-Status and one Stock-Level transaction is generated for every ten New-Order transactions. A "remote terminal emulator" (RTE) is programmed to simulate a user's data entry, typing delays, inter-field and inter-transaction delays. The RTE also keeps track of the time between the user's request of each transaction and its completion, called response time. The rate of New-Order transactions executed per minute is reported as the tpmC value (transaction per minute C) and represents the primary performance metric of the benchmark.
Early results indicated that in comparison to TPC-A, TPC-C's workload was roughly ten times as complex. Only one transaction type out of five, 44% of the total, is included in the transaction-per-minute TPC-C result, while TPC-A is measured in transactions-per-second and includes every transaction. This means the two numbers are not directly comparable without some conversion, multiplying by 60 to account for seconds-to-minutes, and 2.3 to account for the subset of transactions included. Considering a single machine, the IBM RS/6000 Model 570, TPC-A returns a value of 129 tpsA, whereas TPC-C returns 365.45 tpmC. Multiplying the tpmC by 2.3 and then dividing by 60 to convert to tpsA terms, the result is 13.5, a difference in performance of about 9.5 times.
Submission of a TPC-C result also requires the disclosure of the detailed pricing of the tested configuration, including hardware and software maintenance with 7/24 coverage over a three-year period. The priced system has to include not only the system itself, but also sufficient storage to hold the data generated by running the system at the quoted tpmC rate over a period of 60 days. In theory, a tpmC of 1 will generate 252 kB of entries in History, 133 in Orders, and 1325 kB in Order-Line. The total system price is combined with the measured tpmC to produce a price/performance metric. While some published results aimed at producing the highest possible tpmC, many more published results have targeted a top spot in the competitive price/performance category, at times with a relatively low tpmC.
The benchmark is typically executed by the vendor of one of the main components (e.g. database system, back-end server, etc.) who has to submit a disclosure report with complete details on the system configuration, its setup, the conditions of the testing and all results collected. The entire benchmark implementation, all testing steps, the measured results, the system pricing and the disclosure report must be validated by an independent auditor certified by the TPC.
References
Citations
Bibliography
Benchmarks (computing) | TPC-C | [
"Technology"
] | 2,481 | [
"Benchmarks (computing)",
"Computing comparisons",
"Computer performance"
] |
69,167,071 | https://en.wikipedia.org/wiki/List%20of%20cryptosystems | A cryptosystem is a set of cryptographic algorithms that map ciphertexts and plaintexts to each other.
Private-key cryptosystems
Private-key cryptosystems use the same key for encryption and decryption.
Caesar cipher
Substitution cipher
Enigma machine
Data Encryption Standard
Twofish
Serpent
Camellia
Salsa20
ChaCha20
Blowfish
CAST5
Kuznyechik
RC4
3DES
Skipjack
Safer
IDEA
Advanced Encryption Standard, also known as AES and Rijndael.
Public-key cryptosystems
Public-key cryptosystems use a public key for encryption and a private key for decryption.
Diffie–Hellman key exchange
RSA encryption
Rabin cryptosystem
Schnorr signature
ElGamal encryption
Elliptic-curve cryptography
Lattice-based cryptography
McEliece cryptosystem
Multivariate cryptography
Isogeny-based cryptography
References
Cryptography
Algorithms | List of cryptosystems | [
"Mathematics",
"Engineering"
] | 193 | [
"Cybersecurity engineering",
"Cryptography",
"Algorithms",
"Mathematical logic",
"Applied mathematics"
] |
69,170,024 | https://en.wikipedia.org/wiki/Predictive%20policing | Predictive policing is the usage of mathematics, predictive analytics, and other analytical techniques in law enforcement to identify potential criminal activity. A report published by the RAND Corporation identified four general categories predictive policing methods fall into: methods for predicting crimes, methods for predicting offenders, methods for predicting perpetrators' identities, and methods for predicting victims of crime.
Methodology
Predictive policing uses data on the times, locations and nature of past crimes to provide insight to police strategists concerning where, and at what times, police patrols should patrol, or maintain a presence, in order to make the best use of resources or to have the greatest chance of deterring or preventing future crimes. This type of policing detects signals and patterns in crime reports to anticipate if crime will spike, when a shooting may occur, where the next car will be broken into, and who the next crime victim will be. Algorithms are produced by taking into account these factors, which consist of large amounts of data that can be analyzed. The use of algorithms creates a more effective approach that speeds up the process of predictive policing since it can quickly factor in different variables to produce an automated outcome. From the predictions the algorithm generates, they should be coupled with a prevention strategy, which typically sends an officer to the predicted time and place of the crime. The use of automated predictive policing supplies a more accurate and efficient process when looking at future crimes because there is data to back up decisions, rather than just the instincts of police officers. By having police use information from predictive policing, they are able to anticipate the concerns of communities, wisely allocate resources to times and places, and prevent victimization.
Police may also use data accumulated on shootings and the sounds of gunfire to identify locations of shootings. The city of Chicago uses data blended from population mapping crime statistics to improve monitoring and identify patterns.
Other approaches
Rather than predicting crime, predictive policing can be used to prevent it. The "AI Ethics of Care" approach recognizes that some locations have greater crime rates as a result of negative environmental conditions. Artificial intelligence can be used to minimize crime by addressing the identified demands.
History
Iraq
At the conclusion of intense combat operations in April 2003, Improvised Explosive Devices (IEDs) were dispersed throughout Iraq’s streets. These devices were deployed to monitor and counteract U.S. military activities using predictive policing tactics. However, the extensive areas covered by these IEDs made it impractical for Iraqi forces to respond to every American presence within the region. This challenge led to the concept of Actionable Hot Spots—zones experiencing high levels of activity yet too vast for effective control. This situation presented difficulties for the Iraqi military in selecting optimal locations for surveillance, sniper placements, and route patrols along areas monitored by IEDs.
China
The roots of predictive policing can be traced to the policy approach of social governance, in which leader of the Chinese Communist Party Xi Jinping announced at a security conference in 2016 is the Chinese regime’s agenda to promote a harmonious and prosperous country through an extensive use of information systems. A common instance of social governance is the development of the social credit system, where big data is used to digitize identities and quantify trustworthiness. There is no other comparably comprehensive and institutionalized system of citizen assessment in the West.
The increase in collecting and assessing aggregate public and private information by China’s police force to analyze past crime and forecast future criminal activity is part of the government’s mission to promote social stability by converting intelligence-led policing (i.e. effectively using information) into informatization (i.e. using information technologies) of policing. The increase in employment of big data through the police geographical information system (PGIS) is within China’s promise to better coordinate information resources across departments and regions to transform analysis of past crime patterns and trends into automated prevention and suppression of crime. PGIS was first introduced in 1970s and was originally used for internal government management and research institutions for city surveying and planning. Since the mid-1990s PGIS has been introduced into the Chinese public security industry to empower law enforcement by promoting police collaboration and resource sharing. The current applications of PGIS are still contained within the stages of public map services, spatial queries, and hot spot mapping. Its application in crime trajectory analysis and prediction is still in the exploratory stage; however, the promotion of informatization of policing has encouraged cloud-based upgrades to PGIS design, fusion of multi-source spatiotemporal data, and developments to police spatiotemporal big data analysis and visualization.
Although there is no nationwide police prediction program in China, local projects between 2015 and 2018 have also been undertaken in regions such as Zhejiang, Guangdong, Suzhou, and Xinjiang, that are either advertised as or are building blocks towards a predictive policing system.
Zhejiang and Guangdong had established prediction and prevention of telecommunication fraud through the real-time collection and surveillance of suspicious online or telecommunication activities and the collaboration with private companies such as the Alibaba Group for the identification of potential suspects. The predictive policing and crime prevention operation involves forewarning to specific victims, with 9,120 warning calls being made in 2018 by the Zhongshan police force along with direct interception of over 13,000 telephone calls and over 30,000 text messages in 2017.
Substance-related crime is also investigated in Guangdong, specifically the Zhongshan police force who were the first city in 2017 to utilize wastewater analysis and data models that included water and electricity usage to locate hotspots for drug crime. This method led to the arrest of 341 suspects in 45 different criminal investigations by 2019.
In China, Suzhou Police Bureau has adopted predictive policing since 2013. During 2015–2018, several cities in China have adopted predictive policing. China has used predictive policing to identify and target people for sent to Xinjiang internment camps.
The integrated joint operations platform (IJOP) predictive policing system is operated by the Central Political and Legal Affairs Commission.
Europe
In Europe there has been significant pushback against predictive policing and the broader use of artificial intelligence in policing on both a national and European Union level.
The Danish POL-INTEL project has been operational since 2017 and is based on the Gotham system from Palantir Technologies. The Gotham system has also been used by German state police and Europol.
Predictive policing has been used in the Netherlands.
United States
In the United States, the practice of predictive policing has been implemented by police departments in several states such as California, Washington, South Carolina, Alabama, Arizona, Tennessee, New York, and Illinois.
In New York, the NYPD has begun implementing a new crime tracking program called Patternizr. The goal of the Patternizr was to help aid police officers in identifying commonalities in crimes committed by the same offenders or same group of offenders. With the help of the Patternizr, officers are able to save time and be more efficient as the program generates the possible "pattern" of different crimes. The officer then has to manually search through the possible patterns to see if the generated crimes are related to the current suspect. If the crimes do match, the officer will launch a deeper investigation into the pattern crimes.
India
In India, various state police forces have adopted AI technologies to enhance their law enforcement capabilities. For instance, the Maharashtra Police have launched Maharashtra Advanced Research and Vigilance for Enhanced Law Enforcement (MARVEL), the country's first state-level police AI system, to improve crime prediction and detection. Additionally, the Uttar Pradesh Police utilize the AI-powered mobile application 'Trinetra' for facial recognition and criminal tracking.
Concerns
Predictive policing faces issues that affect its effectiveness. Obioha mentions several concerns raised about predictive policing. High costs and limited use prevent more widespread use, especially among poorer countries. Another issue that affects predictive policing is that it relies on human input to determine patterns. Flawed data can lead to biased and possibly racist results. Technology cannot predict crime, it can only weaponize proximity to policing. Though it is claimed to be unbiased data, communities of color and low income are the most targeted. It should also be noted that not all crime is reported, making the data faulty and inaccurate.
In 2020, following protests against police brutality, a group of mathematicians published a letter in Notices of the American Mathematical Society urging colleagues to stop work on predictive policing. Over 1,500 other mathematicians joined the proposed boycott.
Some applications of predictive policing have targeted minority neighborhoods and lack feedback loops.
Cities throughout the United States are enacting legislation to restrict the use of predictive policing technologies and other “invasive” intelligence-gathering techniques within their jurisdictions.
Following the introduction of predictive policing as a crime reduction strategy, via the results of an algorithm created through the use of the software PredPol, the city of Santa Cruz, California experienced a decline in the number of burglaries reaching almost 20% in the first six months the program was in place. Despite this, in late June 2020 in the aftermath of the murder of George Floyd in Minneapolis, Minnesota along with a growing call for increased accountability amongst police departments, the Santa Cruz City Council voted in favor of a complete ban on the use of predictive policing technology.
Accompanying the ban on predictive policing, was a similar prohibition of facial recognition technology. Facial recognition technology has been criticized for its reduced accuracy on darker skin tones - which can contribute to cases of mistaken identity and potentially, wrongful convictions.
In 2019, Michael Oliver, of Detroit, Michigan, was wrongfully accused of larceny when his face registered as a “match” in the DataWorks Plus software to the suspect identified in a video taken by the victim of the alleged crime. Oliver spent months going to court arguing for his innocence - and once the judge supervising the case viewed the video footage of the crime, it was clear that Oliver was not the perpetrator. In fact, the perpetrator and Oliver did not resemble each other at all - except for the fact that they are both African-American which makes it more likely that the facial recognition technology will make an identification error.
With regards to predictive policing technology, the mayor of Santa Cruz, Justin Cummings, is quoted as saying, “this is something that targets people who are like me,” referencing the patterns of racial bias and discrimination that predictive policing can continue rather than stop.
For example, as Dorothy Roberts explains in her academic journal article, Digitizing the Carceral State, the data entered into predictive policing algorithms to predict where crimes will occur or who is likely to commit criminal activity, tends to contain information that has been impacted by racism. For example, the inclusion of arrest or incarceration history, neighborhood of residence, level of education, membership in gangs or organized crime groups, 911 call records, among other features, can produce algorithms that suggest the over-policing of minority or low-income communities.
See also
Carding (police policy)
Crime analysis
Crime hotspots
Jurimetrics
Pre-crime
Preventive state
Quantitative methods in criminology
Racial profiling
References
Further reading
Crime prevention
Criminology
Government by algorithm
Law enforcement techniques
Types of policing | Predictive policing | [
"Engineering"
] | 2,282 | [
"Government by algorithm",
"Automation"
] |
69,170,876 | https://en.wikipedia.org/wiki/RS1%20%28rocket%29 | The RS1 is ABL Space Systems's main launch vehicle platform. Both stages are powered by ABL's E2 rocket engine, with nine to eleven in the first stage, and one in the second stage. They are powered by RP-1 or Jet-A kerosene as propellant and liquid oxygen (LOX) as the oxidizer.
The containerized launch system and rocket can be deployed to and launched from a suitably flat site, the main requirements being access for trucks capable of carrying up to -long ISO containers (for the RS-1 first stage), and a flat concrete pad x .
History
In 2020, ABL Space Systems was planning the first orbital launch of its RS1 rocket in 2022. The firm received contracts worth US$44.5 million from the United States Air Force, as well as private funding equaling US$49 million. According to Dan Piemont, the US$44.5 million Air Force contracts include a one-year deal from the tech incubator AFWERX to demonstrate launch technology and an agreement with Space and Missile Systems Center's Space Enterprise Consortium to conduct three demonstrations of a RS1 vehicle variant and deployable ground infrastructure in 2022.
The RS1 claims to be capable of carrying a payload of to low Earth orbit. It is tall. Launches where planned to be sold for US$12 million per flight.
ABL had over 70 launch agreements.
The maiden flight on January 10, 2023, failed after a fire in the aft cavity damaged key harnessing, causing the engines to shut down 11 seconds into flight. RS1 crashed down near the launch pad, damaging infrastructure at the Pacific Spaceport Complex. The second attempt at launch failed on July 19, 2024 due to a static fire testing failure. After the second flight failure, ABL decided to terminate their commercial launch program, and instead focusing on turning RS1 into a missile defense launch vehicle.
ABL is also currently developing a modified RS1 with first stage engine replaced with an aerospike engine, as part of AFRL's ARISE program. In September 2022, AFRL designated X plane number X-63 to this modified RS1 configuration. A test launch was initially scheduled for 2023, but has now since been delayed to an unspecified time.
Previous design
In 2019, RS1 was planned to have three E1 engines, each producing of thrust to power the rocket's first stage. A single E2 engine, with of thrust, was planned for the rocket's second stage. Both engines would use liquid oxygen and RP-1 propellants. The first development build of the vehicle has been completed.
Testing
In 2019, ABL Space conducted testing of the E2 rocket engine at the company's test facilities at Spaceport America, New Mexico, which "provided the perfect location and support staff for us to test the E2 rocket engine". The test was considered a success.
In early 2020, the Air Force Research Laboratory (AFRL) joined with ABL Space Systems to test and develop rocket-propulsion components. In October 2020, the second stage with E2 engine was tested at Edwards Air Force Base.
On 19 January 2022, an anomaly during testing at Mojave Air and Space Port resulted in the destruction of the second stage of the RS1 rocket. On 27 January, the source of the anomaly was publicly identified by ABL's CEO Harry O'Hanley as being one of the second stage's E2 Vacuum engine's turbopumps suffering a hard start, which led to a "substantial fire on the aft end of the vehicle, resulting in a complete failure about 20 seconds later".
After three earlier attempts to launch their RS1 rocket in December 2022, ABL shifted the launch attempt to January 2023. The maiden flight on January 10, 2023 failed.
The second attempt at an orbital launch (DEMO-2 mission) was precluded as the rocket being prepared for that launch suffered irreparable damage in a fire at the launch pad following a static-fire test on 19 July 2024.
Launches sites
Pacific Spaceport Complex
The first RS1 flight was planned for 2022 from the Pacific Spaceport Complex on Kodiak Island, but the launch attempt was aborted. After two additional aborts, the first launch occurred on January 10, 2023. The maiden flight also failed and did not reach orbit.
Cape Canaveral
On 1 November 2021, Amazon announced that the first two prototype satellites of the Kuiper constellation, KuiperSat-1 and KuiperSat-2, would be launched using RS1 in the fourth quarter of 2022 from Launch Complex 48 at the Kennedy Space Center. Amazon subsequently shifted these satellites to Vulcan Centaur, subsequently moving them to an Atlas V launch on October 6, 2023. Meanwhile on March 7th, 2023, it was announced that the Space Force allocated ABL Space Space Launch Complex 15 (SLC-15).
SaxaVord Spaceport
On 7 February 2021, Lockheed Martin and the United Kingdom announced a contract with ABL to launch the UK Pathfinder mission (6 CubeSats) in 2022, from the Shetland Space Centre on the island of Unst, Scotland. The UK Pathfinder launch was scheduled to take place in late 2024.
Launches
See also
Rocket Lab Electron
Firefly Alpha
References
External links
RS-1 rocket details
launch system details
Aerospace technologies
Rocket engines | RS1 (rocket) | [
"Technology"
] | 1,114 | [
"Rocket engines",
"Engines"
] |
69,171,533 | https://en.wikipedia.org/wiki/COVID%20Moonshot | The COVID Moonshot is a collaborative open-science project started in March 2020 with the goal of developing an un-patented oral antiviral drug to treat SARS-CoV-2, the virus causing COVID-19.
COVID Moonshot researchers are targeting the proteins needed to form functioning new viral proteins. They are particularly interested in proteases such as 3C-like protease (Mpro), a coronavirus nonstructural protein that mediates the breaking and replication of proteins.
COVID Moonshot may be the first open-science community effort for the development of an antiviral drug. Hundreds of scientists around the world, from academic and industrial organizations, have shared their expertise, resources, data, and results to more rapidly identify, screen, and test candidate compounds for the treatment of COVID-19.
Project history
Development of antiviral drugs is a complicated and time-consuming multistage process. The public sharing of information in the early stages of genome identification and protein structure identification has accelerated the process of searching for COVID-19 treatments and established a basis for the COVID Moonshot initiative.
Genome identification
On January 3, 2020, Chinese virologist Yong-Zhen Zhang of Fudan University and the Shanghai Public Health Clinical Center received a test sample from Wuhan, China, where patients had a pneumonia-like illness. By January 5, Zhang and his team had sequenced a virus from the sample and deposited its genome on GenBank, an international research database maintained by the United States National Center for Biotechnology Information.
By January 11, 2020, Edward C. Holmes of the University of Sydney had Zhang's permission to publicly release the genome.
Protein structures
With that information, structural biologists world-wide began examining its protein structures. Investigators from the Center for Structural Genomics of Infectious Diseases (CSGID) and other groups began working to characterize the 3D structure of the proteins, sharing their results via the Protein Data Bank (PDB).
Scientists were able to identify a key protein in the virus: 3C-like protease (Mpro).
Crucial early X-ray crystallography was done by Zihe Rao and Haitao Yang in Shanghai, China. On January 26, 2020, they submitted a structure of Mpro bound to an inhibitor to the Protein Data Bank. It was released as of February 5, 2020.
Rao began coordinating with David Stuart and Martin Walsh at Diamond Light Source, the United Kingdom's synchrotron facility. The Diamond group was able to develop and release a high-resolution crystal structure of unbound Mpro.
Approaches to accelerating drug development have been suggested, but identification of proteins and drug development commonly take years. It was possible to sequence the virus and characterize key proteins extremely quickly because the new virus was somewhat familiar. It had a 70–80% sequence similarity to the proteins in the SARS-CoV coronavirus that caused the SARS outbreak in 2002. Researchers could therefore build on what was already known about previous coronaviruses.
Possible targets
Identifying and recreating viral proteins in the lab is a first step to developing drugs to attack them and vaccines to protect against them. The COVID Moonshot initiative follows an approach to structure-based drug design in which researchers attempt to find a molecule that will bind tightly to a drug target and prevent it from carrying out its normal activities.
In the case of SARS-CoV-2, the coronavirus enters the body and then replicates its genomic RNA, building new copies that are incorporated into new, rapidly spreading viral particles. Protease enzymes or proteases are often desirable drug targets, because proteases are important in the formation and spreading of viral particles. Inhibition of viral proteases can inhibit the virus's ability to replicate itself and spread.
3C-like protease (Mpro), a coronavirus nonstructural protein, is one of the main proteins involved in the replication and transcription of SARS-CoV-2. By understanding Mpro's structure and the ways in which it functions, scientists can identify possible candidates to preemptively bind to Mpro and block its activity. Mpro is not the only possible target for drug design, but it is a highly interesting one.
Fragment screening
In collaboration with the University of Oxford and the Weizmann Institute of Science in Rehovot, Israel, the facilities at Diamond Light were used to develop fragment screens utilizing crystallography and mass spectrometry.
Nir London's laboratory at the Weizmann Institute contributed technology for identifying compounds that bind irreversibly to target proteins.
Frank von Delft and the Nuffield Department of Medicine at the University of Oxford provided technology for rapid crystallographic fragment screening.
Researchers examined thousands of possible fragments from diverse screening libraries and identified at least 71 possible protein–ligand crystal structures, chemical fragments which might have the potential to bind to Mpro.
These results were immediately made available online.
Designing candidates
The open release of the data and its announcement on Twitter on March 7, 2020, mark a critical point in the formation of COVID Moonshot. The scientists shared their information and challenged chemists worldwide to use that information to design potential openly available antiviral drug candidates. They expected a couple of hundred submissions. By May 2020 more than 4,600 design submissions for potential inhibitors were received. By January 2021, the number of unique compound designs had risen to 14,000. In response, those involved began to shift from a spontaneous virtual collaboration to a larger and more organized network of partners with specialized skills and well-articulated goals.
The design submissions were stored in Collaborative Drug Discovery's CDD Vault, a database used for large-scale management of chemical structures, experimental protocols and experimental results.
Alpha Lee and Matt Robinson brought computational expertise from PostEra to the project. PostEra used techniques from artificial intelligence and machine learning to develop analysis tools for computational drug discovery, chemical synthesis and biochemical assays. When COVID Moonshot's appeal resulted in not hundreds but thousands of responses, they built a platform capable of triaging large numbers of compounds and designing routes for their synthetic formation.
Supercomputer access was provided through the COVID-19 High Performance Computing (HPC) Consortium, accelerating the speed at which designs could be examined and compared. The distributed supercomputing initiative Folding@home has carried out multiple sprints to model novel protein structures and target desirable structures as a part of COVID Moonshot.
Many of the criteria for selecting drug candidates were determined by the group's goals. An ideal drug candidate would be effective in treating COVID-19. It also would be easily and cheaply made, so that as many countries and companies as possible could produce and distribute it. The ingredients to make it should be easy to obtain, and the processes involved should be as simple as possible. A drug shouldn't require special handling (like refrigeration) and it should be easy to administer (a pill rather than an injection).
In a matter of months, researchers were able to identify more than 200 promising crystal structure designs and to begin creating and testing them in the lab.
Chris Schofield at the University of Oxford synthesized and tested 4 of the most promising of the novel designed peptides to demonstrate their ability to block and inhibit Mpro.
Freely available data from COVID Moonshot has also been used to assess the predictive ability of docking scores in suggesting the potency of SARS-CoV-2 M-pro inhibitors.
To go beyond the design phase, possible drug candidates must be created and tested for both effectiveness and safety in animal and human trials. The Wellcome Trust has committed to key initial funding to support this process. Synthesis of candidates is being carried out in parallel, at sites including Ukraine (Enamine), India (Sai Life Sciences) and China (WuXi). Annette von Delft of the University of Oxford and the National Institute for Health Research (NIHR)'s Oxford Biomedical Research Centre (BRC) is leading pre-clinical small molecule research related to COVID Moonshot.
Potential for antiviral treatments
COVID Moonshot anticipates that they will select three pre-clinical candidates by March 2022, to be followed by preclinical safety and toxicology testing and identification of needed chemistry, manufacturing and control (CMC) steps. Based on that data, the most promising candidate will be chosen. Phase-1 clinical trials, the first stage of testing in human subjects, are projected to begin by June 2023.
Unlike a vaccine, which increases immunity and protects against catching an infectious disease, an antiviral drug treats someone who is already sick by attacking the virus and countering its effects, potentially lessening both symptoms and further transmission.
Mpro is present in other coronaviruses that cause disease, so an antiviral drug that targets Mpro may also be effective against coronaviruses such as SARS and MERS and future pandemics.
Mpro does not mutate easily, so it is less likely that variants of the virus will adapt that can avoid the effects of such a drug.
Open science
Among the many participants in the COVID Moonshot project are the
University of Oxford,
University of Cambridge,
Diamond Light Source,
Weizmann Institute of Science in Rehovot, Israel,
Temple University,
Memorial Sloan Kettering Cancer Center,
PostEra,
University of Johannesburg,
and the
Drugs for Neglected Diseases initiative (DNDi) in Switzerland.
Support for the project has come from a variety of philanthropic sources including the Wellcome Trust,
COVID-19 Therapeutics Accelerator (CTA),
Bill & Melinda Gates Foundation,
LifeArc,
and through crowdsourcing.
Because COVID Moonshot is based in open science and shared open data, any drug that the project develops can be manufactured and sold by whoever wishes to produce it, worldwide. Countries that are unable to buy or manufacture expensive licensed drugs would therefore have the opportunity to produce their own supplies, and competition between suppliers is likely to result in greater availability and reduced prices for consumers.
This would circumvent issues around the time needed to vaccinate people worldwide. As of July 2021, it was estimated that at current rates, this was likely to take several years. Inequities in distribution will increase both the spreading of the virus and the risk that new and more dangerous variants will emerge.
Supporters of the COVID Moonshot initiative have argued that open-science drug discovery is an essential model for combating both current and future pandemics, and that the prevention of the spread of pandemic diseases is an essential public service.
References
External links
Antiviral drugs
Collaborative projects
Genome databases
International medical and health organizations
Open data
Open science
Proteins
SARS-CoV-2
Scientific organisations based in England | COVID Moonshot | [
"Chemistry",
"Biology"
] | 2,212 | [
"Biomolecules by chemical classification",
"Antiviral drugs",
"Molecular biology",
"Proteins",
"Biocides"
] |
69,172,875 | https://en.wikipedia.org/wiki/Strip%20the%20Cosmos | Strip the Cosmos is a documentary science television series narrated by Eric Loren. Aired by the Science Channel, it premiered on November 12, 2014.
Content
Strip The Cosmos builds upon a concept introduced in an earlier show, Strip the City — in which layers of a city were "stripped" away with computer-generated imagery to reveal what lay beneath them — and applies it to the universe as a whole. The series "strips" away layers of objects such as stars, planets, moons, comets, and black holes to reveal their interiors layer by layer and create a better understanding of how they originated, what makes them up, and how they work, with commentary by experts in astronomy and astrophysics. The series also describes space missions intended to expand human understanding of the universe.
Episode list
Season 1 (2014)
SOURCES Windfall Films Strip the Cosmos Series 1 Episode 1 Secrets of the Black Hole Accessed 31 October 2021Windfall Films Strip the Cosmos Series 1 Episode 3 Killer Asteroids Accessed 31 October 2021Windfall Films Strip the Cosmos Series 1 Episode 5 Alien Worlds Accessed 31 October 2021
Season 2 (2017)
SOURCES Windfall Films Strip the Cosmos Series 2 Episode 1 Secrets of the Black Hole Accessed 31 October 2021Windfall Films Strip the Cosmos Series 2 Episode 3 Hunt for the Big Bang Accessed 31 October 2021Windfall Films Strip the Cosmos Series 2 Episode 5 Mystery of the Hidden Universe Accessed 31 October 2021
Season 3 (2018)
SOURCES Windfall Films Strip the Cosmos Series 3 Episode 1 Mystery of the Alien Asteroid Accessed 31 October 2021Windfall Films Strip the Cosmos Series 3 Episode 3 The Moon's Dark Secret Accessed 31 October 2021Windfall Films Strip the Cosmos Series 3 Episode 5 Secret History of the Solar System Accessed 31 October 2021Windfall Films Strip the Cosmos Series 3 Episode 7 Secrets of the Alien Megastructure Accessed 31 October 2021Windfall Films Strip the Cosmos Series 3 Episode 9 Pluto's Strange Secrets Revealed Accessed 31 October 2021
Season 4 (2020)
SOURCES Windfall Films ‘’Strip the Cosmos’’ Series 4 Episode 1 Mission to Mars Accessed 1 November 2021Windfall Films ‘’Strip the Cosmos’’ Series 4 Episode 3 Life and Death of the Milky Way Accessed 1 November 2021Films ‘’Strip the Cosmos’’ Series 4 Episode 5 Secrets of the Asteroids Accessed 1 November 2021Windfall Films ‘’Strip the Cosmos’’ Series 4 Episode 7 Mystery of the Dead Planets Accessed 1 November 2021
See also
Alien Planet
Cosmos: A Spacetime Odyssey
Extreme Universe
How the Universe Works
Into the Universe with Stephen Hawking
Killers of the Cosmos
Mars: The Secret Science
The Planets and Beyond
Space's Deepest Secrets
Strip the City
Through the Wormhole
The Universe
References
External links
Windfall Films Strip the Cosmos
2014 American television series debuts
2010s American documentary television series
2020s American documentary television series
Documentary television series about astronomy
Science Channel original programming | Strip the Cosmos | [
"Astronomy"
] | 564 | [
"Documentary television series about astronomy",
"Works about astronomy"
] |
69,173,018 | https://en.wikipedia.org/wiki/CG%20Cygni | CG Cygni is a ternary star system composed of main-sequence stars in the constellation of Cygnus about away.
System
The star CG Cygni A (BD+34 4217A) itself is a close binary system with ongoing mass transfer between components. The orbital period of the binary is currently increasing. An additional third body (either star or planet) was suspected to exist in the system with an orbital period of 15.9-51 years, creating cyclic period variations of the binary. It was finally confirmed as the star CG Cygni B (BD+34 4217B) in 2020, at a 1.16 arcsecond separation from the primary.
Properties
The primary, BD+34 4217Aa, has a large number of starspots covering up to 18% of its surface. These are located in low latitudes, usually perpendicular to the line connecting the stars Aa and Ab, although reversal of the starspots positions was detected in 1991, 2003 and 2008.
References
Triple star systems
RS Canum Venaticorum variables
Cygnus (constellation)
103505
J20581343+3510298
BD+34 4217
Cygni, CG | CG Cygni | [
"Astronomy"
] | 250 | [
"Cygnus (constellation)",
"Constellations"
] |
69,173,182 | https://en.wikipedia.org/wiki/DASH%20%28satellite%29 | DASH (short for Density And Scale Height) were a pair of 2.5 meter balloon satellites launched in 1963. They were designed to measure air density at very high altitude, but their orbit was significantly affected by solar radiation pressure.
References
Satellites of the United States
1963 in spaceflight | DASH (satellite) | [
"Astronomy"
] | 58 | [
"Astronomy stubs",
"Spacecraft stubs"
] |
69,174,888 | https://en.wikipedia.org/wiki/August%20Friedrich%20Horstmann | August Friedrich Horstmann (20 November 1842 – 8 October 1929) was a German physical chemist who contributed to a thermodynamic understanding of chemical reactions and equilibria. His mathematical approach published in 1873 was largely overshadowed by the independent and identical findings of Josiah Willard Gibbs made about three years later.
Horstmann was born in Mannheim where his parents Georg Friedrich and Charlotte Friederike née Köhler ran a grocery business. He went to the Lycaeum and dropped out of high school due to short-sight and worked with his father. After three years he decided to study again and went to Heidelberg in 1862 where he attended chemistry classes under Emil Erlenmeyer. In 1865 he received a doctorate and went to study in Zurich under Johannes Wislicenus and Rudolf Clausius followed in 1866 with studies at Bonn with Hans Heinrich Landolt. He examined molecular weight and specific gravity of liquids. He became an associate professor in 1870 but short sight was still a problem and few students joined him. His major work was on the application of the laws of thermodynamics to chemical equilibria.
Horstmann married Clothilde Henriette Gernandt (1844–1921) in 1873 and they had five children. He went blind in 1902.
References
External links
Abhandlungen zur Thermodynamik chemischer Vorgänge (1903)
1842 births
1929 deaths
Physical chemists
People from Mannheim | August Friedrich Horstmann | [
"Chemistry"
] | 288 | [
"Physical chemists"
] |
69,175,104 | https://en.wikipedia.org/wiki/Porsche%20V10%20engine | The Porsche V10 engine is a naturally-aspirated, V-10, internal combustion piston engine, designed and developed by Porsche, originally as a concept design for Formula One motor racing in the 1990s, and later Le Mans racing, but eventually used in the Porsche Carrera GT sports car; between 2003 and 2007. The engine is derived from the unsuccessful Porsche 3512 3.5-liter 80° V12 engine, used in the early 1990s.
Background
A V10 replacement for the 3512 was in development at the time of Porsche's withdrawal from Formula One. This engine would not be completed until several years later, when it was modified for use in the stillborn Porsche LMP project in 2000. The engine design eventually was re-used when a further variant was chosen as the powerplant of the Porsche Carrera GT supercar.
Technical specifications
Porsche Carrera GT Engine
Layout: Longitudinal, rear mid-engine, rear-wheel-drive layout
Engine type: 68° V10, aluminium block and heads
Code: 980/01
Valvetrain: DOHC (chain-driven), 4 valves per cylinder (40 valves total), variable valve timing on intake camshafts, sodium-cooled exhaust valves
Bore × stroke: , Nikasil coated bores, forged titanium connecting rods, forged pistons
Displacement:
Compression ratio: 12.0:1
Rated power: @ 8,000 rpm
Max. torque: @ 5,750 rpm
Specific output:
Weight to power ratio:
Power to weight ratio:
Redline: 8,400 rpm
Applications
Road cars
Porsche Carrera GT (M80/01)
Race cars
Porsche LMP2000 (9R3)
References
Porsche
Engines by model
Gasoline engines by model
Formula One engines
Porsche in motorsport
V10 engines | Porsche V10 engine | [
"Technology"
] | 355 | [
"Engines",
"Engines by model"
] |
69,175,213 | https://en.wikipedia.org/wiki/Superposition%20Benchmark | Superposition Benchmark is a benchmarking software based on the UNIGINE Engine. The benchmark was developed and published by UNIGINE Company in 2017. The main purpose of software is performance and stability testing for GPUs. Users can choose a workload preset, Low to Extreme, or set the parameters by custom. The benchmark 3D scene is an office of a fictional genius scientist from the middle of the 20th century. The scene is GPU-intensive because of SSRTGI (Screen-Space Ray-Traced Global Illumination), proprietary dynamic lighting technology by Unigine.
Superposition and other benchmarks by Unigine are often used by hardware reviewers to measure graphics performance (PCMag, Digital Trends, Lifewire and others) and by overclockers for online and offline competitions in GPU overclocking. Running Superposition (or another) benchmark by Unigine produces a performance score: the higher the numbers, the better the performance. Users can compare different configurations in the online leaderboards.
Technological features
Visuals powered by UNIGINE 2 Engine
Support for Windows 7 SP1 x64, Windows 8 x64, Windows 10 x64, Linux x64, macOS
Extreme hardware stability testing
GPU temperature and clock monitoring
Unique SSRTGI (Screen-Space Ray-Traced Global Illumination) dynamic lighting technology
VR experience (Oculus Rift and HTC Vive)
Free exploration mode with mini-games
Over 900 interactive objects
Global leaderboards integration
See also
Benchmark
Overclocking
References
Benchmarks (computing) | Superposition Benchmark | [
"Technology"
] | 317 | [
"Benchmarks (computing)",
"Computing comparisons",
"Computer performance"
] |
69,175,518 | https://en.wikipedia.org/wiki/Activity%20space | In social science, the activity space designates the "set of places individuals encounter as a result of their routine activities in everyday life."
The activity space can include all relevant locations that an individual routinely go to, such as the place of residence, the workplace (or the place of study), but also gyms, supermarkets, or cinemas.
Definition
Activity space research started in the field of geography and urban planning, where scholars investigated the effect of urban spatial structure on individual behavior. Horton and Reynolds define the activity space "as the subset of all urban locations with which the individual has direct contact as the result of day-to-day activities." They consider the activity space as a subset of one's "action space," which they define as "the collection of all urban locations about which the individual has information and the subjective utility or preference he associates with these locations". The "action space" is often use synonymously with the terms "awareness space," "mental map," and "cognitive map."
The emergence of the cognitive science has broadened the scope of activity space beyond the realm of physicality. Scientists like David Kirsh define activity space as the blend of several components. These components include:
The goal a task is meant to accomplish or problem it is meant to resolve
The physical space the task is performed within
The actions an "agent" is capable of taking
The concepts, plans, and other abstract resources agents find in the environment or bring to the task in their minds
See also
Absolute space and time
Method of loci
Social space
Sociology of space
Spatial analysis
Spatial memory
Time geography
References
Social concepts
Geography terminology
Urban geography
Spatial analysis | Activity space | [
"Physics"
] | 335 | [
"Spacetime",
"Space",
"Spatial analysis"
] |
69,175,691 | https://en.wikipedia.org/wiki/List%20of%20fungi%20of%20South%20Africa%20%E2%80%93%20R | This is an alphabetical list of fungal taxa as recorded from South Africa. Currently accepted names have been appended.
Ra
Genus: Radulum Fr. 1825, accepted as Xenotypa Petr., (1955)
Radulum javanicum (Henn.) Lloyd 1915 accepted as Erythricium salmonicolor (Berk. & Broome) Burds., (1985)
Radulum lirellosum Lloyd.
Radulum mirabile Berk. & Broome 1873 accepted as Lopharia cinerascens (Schwein.) G. Cunn., (1956)
Radulum orbiculare Fr. 1825 accepted as Xylodon radula (Fr.) Ţura, Zmitr., Wasser & Spirin, (2011)
Genus: Ramalina Ach. 1809 (Lichens)
Ramalina angulosa Laurer ex Th. Fr. 1861 accepted as Ramalina australiensis Nyl., (1870)
Ramalina arabum (Dill. ex Ach.) Meyen & Flot. 1843
Ramalina australiensis Nyl., (1870) reported as Ramalina angulosa Laurer ex Th. Fr. 1861
Ramalina bourgaeana Mont. ex Nyl. as bourgeana 1870 accepted as Niebla bourgaeana (Mont. ex Nyl.) Rundel & Bowler [as bourgeana], (1978)
Ramalina calicaris (L.) Röhl. 1813
Ramalina calicaris f. ecklonii (Spreng.) Nyl. 1860, accepted as Ramalina ecklonii (Spreng.) Meyen & Flot. [as 'eckloni'], (1843)
Ramalina capensis var. angulosa Th. Fr. 1861
Ramalina capensis var. melanothrix (Laurer) Th. Fr. 1861 accepted as Niebla melanothrix (Laurer) Kistenich, Timdal, Bendiksby & S. Ekman, (2018)
Ramalina celastri (Spreng.) Krog & Swinscow, (1976) reported as Ramalina linearis (Sw.) Ach. 1810
Ramalina complanata (Sw.) Ach. 1810
Ramalina cuspidata (Ach.) Nyl. 1870
Ramalina cuspidata f. implexa H. Olivier 1892
Ramalina dendriscoides Nyl. 1876
Ramalina denticulata (Eschw.) Nyl. 1863
Ramalina duriaei Jatta (sic) possibly (De Not.) Bagl. 1879, accepted as Ramalina lacera (With.) J.R. Laundon, (1984)
Ramalina ecklonii (Spreng.) Meyen & Flot. 1843
Ramalina euphorbiae Vain. 1901
Ramalina evernioides Nyl. 1857
Ramalina farinacea (L.) Ach. 1810
Ramalina farinacea var. squarrosa Müll. Arg. 1883 accepted as Ramalina peruviana Ach., (1810)
Ramalina fastigiata (Pers.) Ach. 1810
Ramalina fraxinea (L.) Ach. 1810
Ramalina fraxinea var. fastigiata (Lilj.) Fr. 1826
Ramalina geniculata Hook. f. & Taylor 1844, accepted as Ramalina inflata (Hook. f. & Taylor) Hook. f. & Taylor, (1845)
Ramalina geniculata f. tenuis Hue.*
Ramalina geniculata var. olivacea Müll. Arg. 1879 accepted as Ramalina inflata (Hook. f. & Taylor) Hook. f. & Taylor, (1845)
Ramalina gracilis (Pers.) Nyl. 1860;
Ramalina implexa Laur. (sic)possibly (Nyl.) Krog 1994
Ramalina inflata (Hook. f. & Taylor) Hook. f. & Taylor, (1845) reported as Ramalina geniculata Hook. f. & Taylor 1844,
Ramalina intermedia (Delise ex Nyl.) Nyl. 1873
Ramalina lacera (With.) J.R. Laundon, (1984) possibly repoerted as Ramalina duriaei Jatta (sic) possibly (De Not.) Bagl. 1879
Ramalina lanceolata Nyl. 1870
Ramalina linearis (Sw.) Ach. 1810 accepted as Ramalina celastri (Spreng.) Krog & Swinscow, (1976)
Ramalina melanothrix Laurer 1860 accepted as Niebla melanothrix (Laurer) Kistenich, Timdal, Bendiksby & S. Ekman, (2018)
Ramalina membranacea Laur. possibly Mont. 1839
Ramalina peruviana Ach., (1810) reported as Ramalina farinacea var. squarrosa Müll. Arg. 1883
Ramalina pollinaria (Westr.) Ach. 1810
Ramalina pollinaria f. cariosa Laurer 1870
Ramalina pusilla Le Prévost ex Duby 1830
Ramalina scopulorum (Ach.) Ach. 1810 accepted as Ramalina siliquosa (Huds.) A.L. Sm., (1918)
Ramalina scopulorum var. cornuata (Ach.) Ach. 1810 accepted as Ramalina cuspidata (Ach.) Nyl., (1870)
Ramalina scopulorum var. humilis Schaer.
Ramalina scopulorum var. implexa Nyl.
Ramalina siliquosa (Huds.) A.L. Sm., (1918) reported as Ramalina scopulorum (Ach.) Ach. 1810
Ramalina subfraxinea Nyl. 1870
Ramalina usnea (L.) R. Howe 1914
Ramalina usnea var. capensis (Nyl.) Zahlbr. 1930;
Ramalina usnea var. contorta (Flot.) Zahlbr. 1930;
Ramalina usneoides (Ach.) Mont. 1837
Ramalina usneoides var. capensis Nyl.
Ramalina usneoides var. contorta Flotow. wccepted as Ramalina usnea (L.) R. Howe 1914
Ramalina webbii var. capensis A. Massal. 1861
Ramalina yemensis (Ach.) Nyl. 1870.
Ramalina yemensis f. fenestralis Stizenb. 1890
Ramalina yemensis f. sublinearis Nyl. 1870
Ramalina yemensis f. tenuissima Müll.Arg.*
Ramalina yemensis var. ecklonii (Spreng.) Vain. 1890
Ramalina yemensis var. lanceolata Nyl.*
Ramalina yemensis var. membranacea (Laurer) Nyl. 1870
Ramalina yemensis var. tenuissima (Meyen & Flot.) Zahlbr. 1930 accep-ted as Ramalina celastri (Spreng.) Krog & Swinscow, (1976)
Genus: Ramularia Unger 1833
Ramularia areola G.F. Atk. 1890 accepted as Ramularia gossypii (Speg.) Cif., (1962)
Ramularia gossypii (Speg.) Cif., (1962) reported as Ramularia areola G.F. Atk. 1890
Ramularia primulae Thüm. 1878
Ramularia richardiae Kalchbr. & Cooke 1880
Ramularia rumicis Kalchbr. & Cooke 1880
Genus: Ravenelia Berk. 1853
Ravenelia atrides Syd. & P. Syd. 1912 accepted as Uredopeltis atrides (Syd. & P. Syd.) A.R. Wood, (2007)
Ravenelia baumiana Henn. 1903
Ravenelia bottomleyae Doidge 1927 accepted as Spumula bottomleyae (Doidge) Thirum., (1946)
Ravenelia deformans (Maubl.) Dietel 1906 accepted as Ravenelia hieronymi Speg., (1881)
Ravenelia dichrostachydis Doidge 1927,
Ravenelia elephantorhizae Doidge 1927
Ravenelia escharoides Syd. & P. Syd. 1912
Ravenelia evansii Syd. & P. Syd. 1912,
Ravenelia glabra Kalchbr. & Cooke 1880
Ravenelia halsei Doidge 1939
Ravenelia hieronymi Speg., (1881) recorded as Ravenelia deformans (Maubl.) Dietel 1906
Ravenelia indigoferae Tranzschel ex Dietel 1894
Ravenelia inornata (Kalchbr.) Dietel 1894
Ravenelia laevis Dietel & Holw. 1897
Ravenelia le-testui Maubl., (1906)
Ravenelia macowaniana Pazschke 1894
Ravenelia minima Cooke 1882
Ravenelia modesta Doidge 1939
Ravenelia munduleae Henn. 1896
Ravenelia natalensis Syd., P. Syd. & Pole-Evans 1912
Ravenelia ornamentalis (Kalchbr.) Dietel 1906
Ravenelia peglerae Pole-Evans 1950
Ravenelia pienaarii Doidge 1927
Ravenelia pretoriensis Syd. & P. Syd. 1912
Ravenelia stictica Berk. & Broome 1873
Ravenelia tephrosiae Kalchbr. 1886.
Ravenelia transvaalensis Doidge 1939
Ravenelia woodii Pazschke 1894,.
Rh
Genus: Rhachomyces Thaxt. 1895
Rhachomyces dolicaontis Thaxt., [as dolichaontis] (1901)
Genus: Rhinocladium Sacc. & Marchal 1885
Rhinocladium beurmanni (Matr. & Ramond) Vuill. 1910 accepted as Sporothrix schenckii Hektoen & C.F. Perkins, (1900)
Genus: Rhinosporidium Minchin & Fantham 1905 (Mesomycetozoea) (Protozoa)
Rhinosporidium kinealyi Minchin & Fantham 1905
Rhinosporidium seeberi (Wernicke) Seeber 1912
Rhinosporidium sp.
Genus: Rhinotrichum Corda 1837
Rhinotrichum curtisii Berk. 1867 accepted as Acladium curtisii (Berk.) M.B. Ellis, (1976)
Rhinotrichum rubiginosum Lloyd (sic) possibly (Fr.) Sumst. 1911 accepted as Botryobasidium rubiginosum (Fr.) Rossman & W.C. Allen, (2016)
Genus: Rhizina Fr. 1815,
Rhizina inflata Karst. (sic) possobly (Schaeff.) Quél. 1886
Rhizina resupinata Lloyd*
Genus: Rhizocarpon Ramond ex DC. 1805 (Lichens)
Rhizocarpon affine G. Merr.
Rhizocarpon badioatrum var. alboatrum Malme 1922, accepted as Rhizocarpon richardii (Lamy ex Nyl.) Zahlbr., (1926)
Rhizocarpon capense Zahlbr. 1936
Rhizocarpon disporum var. montagnei (Flot.) Zahlbr. 1926, accepted as Rhizocarpon disporum (Nägeli ex Hepp) Müll. Arg., (1879)
Rhizocarpon geographicum (L.) DC. 1805
Rhizocarpon geographicum f. atrovirens (L.) A. Massal. 1853 accepted as Rhizocarpon geographicum (L.) DC. 1805
Rhizocarpon geographicum f. intermedium (Stizenb.) Zahlbr. 1926
Rhizocarpon montagnei Körb. 1855 accepted as Rhizocarpon disporum (Nägeli ex Hepp) Müll. Arg., (1879)
Rhizocarpon patellarium (Stizenb.) Zahlbr. 1926
Rhizocarpon richardii (Lamy ex Nyl.) Zahlbr., (1926) recorded as Rhizocarpon badioatrum var. alboatrum Malme 1922,
Rhizocarpon viridiatrum (Wulfen) Körb. 1855
Genus: Rhizoctonia DC. 1815
Rhizoctonia bataticola (Taubenh.) E.J.Butler, (1925), accepted as Macrophomina phaseolina (Tassi) Goid. (1947)
Rhizoctonia crocorum (Pers.) DC. 1815 accepted as Helicobasidium purpureum (Tul.) Pat. 1885
Rhizoctonia lamellifera W.Small (1924), accepted as Macrophomina phaseolina (Tassi) Goid. (1947)
Rhizoctonia solani J.G. Kühn 1858
Rhizoctonia sp.
Genus: Rhizomyces
Rhizomyces confusus Thaxt.
Genus: Rhizopogon
Rhizopogon capfcnsis Lloyd ex Verw.
Rhizopogon luteolus Fr.
Rhizopogon niger Zeller & Dodge.
Rhizopogon pachyphloeus Zeller & Dodge.
Rhizopogon radicans Lloyd
Rhizopogon rubescens Tul.
Genus: Rhizopus
Rhizopus arhizus Fisch.
Rhizopus artocarpi Racib. (1900), accepted as Rhizopus stolonifer Vuillemin (1902)
Rhizopus nigricans Ehrenberg (1820), accepted as Rhizopus stolonifer (Ehrenb.) Vuill., (1902)
Rhizopus stolonifer (Ehrenb.) Vuill., (1902),
Genus: Rhodopaxillus Maire 1913, accepted as Lepista (Fr.) W.G. Sm., (1870)
Rhodopaxillus caffrorum (Kalchbr. & MacOwan) Singer 1942 accepted as Lepista caffrorum (Kalchbr. & MacOwan) Singer, (1951)
Genus: Rhodotorula F.C. Harrison 1927
Rhodotorula mucilaginosa (A. Jörg.) F.C. Harrison 1928
Genus: Rhopalospora*
Rhopalospora caffra Massal.*
Genus: Rhynchosphaeria (Sacc.) Berl. 1890
Rhynchosphaeria fagarae Doidge 1941
Genus: Rhynchosporium Heinsen ex A.B. Frank 1897,
Rhynchosporium secalis (Oudem.) Davis 1919
Genus: Rhytisma Fr. 1819
Rhytisma eugeniacearum Corda 1840
Rhytisma grewiae Kalchbr. 1880 accepted as Phyllachora grewiae (Kalchbr.) Theiss. & Syd., (1915)
Rhytisma melianthi Thüm. 1876 accepted as Phyllachora melianthi (Thüm.) Sacc., (1883)
Rhytisma myricae Mont. 1856
Rhytisma porrigo Cooke 1882 accepted as Cycloschizon porrigo (Cooke) Arx, (1962)
Ri
Genus: Ricasolia A.Massal. (1855), accepted as Solenopsora A.Massal. (1855) (Lichens)
Ricasolia crenulata var. stenospora Nyl. 1859
Ricasolia erosa (Eschw.) Nyl. 1860 accepted as Emmanuelia erosa (Eschw.) Lücking, M. Cáceres & Ant. Simon, (2020)
Ricasolia patinifera (Taylor) Müll. Arg. 1888 accepted as Emmanuelia patinifera (Taylor) Lücking, M. Cáceres & Ant. Simon, (2020)
Ricasolia ravenelii (Tuck.) Nyl. 1863 accepted as Emmanuelia ravenelii (Tuck.) Ant. Simon & Goffinet, (2020)
Ricasolia sublaevis Nyl. 1868
Genus: Rinodina (Ach.) Gray 1821 (Lichens)
Rinodina aethalea Ach.*
Rinodina albotincta (sic) Zahlbr. possibly Rinodina albocincta Zahlbr., (1936)
Rinodina bicolor Zahlbr. 1932
Rinodina capensis Hampe 1861
Rinodina confragulosa (sic) Müll.Arg. possibly Rinodina confragosula (Nyl.) Müll. Arg. 1887,
Rinodina conspersa Müll. Arg. 1889
Rinodina deminutula (Stizenb.) Zahlbr. 1931
Rinodina detecta (Stizenb.) Zahlbr. 1931
Rinodina exigua (Ach.) Gray 1821
Rinodina ficta (Stizenb.) Zahlbr. 1931
Rinodina hufferiana (sic) Müll.Arg. probably Rinodina huefferiana Müll. Arg. 1880
Rinodina huillensis Vain. 1901
Rinodina microlepida Müll. Arg. 1888
Rinodina microphthalma A. Massal. 1861
Rinodina oreina (Ach.) A. Massal. 1852, accepted as Dimelaena oreina (Ach.) Norman, (1852)
Rinodina roboris (Dufour ex Nyl.) Arnold 1881
Rinodina sophodes (Ach.) A. Massal. 1852
Rinodina sophodes var. atroalbida (Nyl.) Zahlbr. 1931 [as atroalba]
Rinodina sophodes var. ledienii Stein 1888
Rinodina teichophiloides (Stizenb.) Zahlbr. 1931 accepted as Rinodina blastidiata Matzer & H. Mayrhofer, (1994)
Genus: Rizalia Syd. & P. Syd. 1914
Rizalia confusa Doidge 1924
Ro
Genus: Roccella DC. 1805 (Lichens)
Roccella arnoldi Vain. 1901
Roccella fuciformis (L.) DC., (1805),
Roccella fucoides (Neck.) Vain. 1901 accepted as Roccella phycopsis Ach., (1810)
Roccella fucoides var. arnoldi (Vain.) Zahlbr. 1915
Roccella hereroensis Vain. 1900
Roccella hypomecha (Ach.) Bory 1828 accepted as Roccellina hypomecha (Ach.) Tehler, (2007)
Roccella hypomecha var. benguellensis Vain. 1901
Roccella hypomecha var. isabellina Vain. 1901
Roccella linearis var. guineensis Vain. 1901
Roccella linearis var. primaria Vain. 1901
Roccella mollusca (Ach.) Nyl. 1858 accepted as Combea mollusca (Ach.) Nyl., (1860)
Roccella montagnei Bél. (1834),
Roccella mossamedana Vain. 1901
Roccella phycopsis Ach. (1810),
Roccella podocarpa Vain. 1901
Roccella tinctoria DC. 1805 accepted as Roccella phycopsis Ach., (1810)
Roccella tinctoria f. complanata Vain. 1901
Roccella tinctoria var. hypomecha (Ach.) Ach. 1810 accepted as Roccellina hypomecha (Ach.) Tehler, (2007)
Roccella tinctoria var. subpodicellata Vain. 1901
Family: Roccellaceae Chevall. 1826
Genus: Rosellinia De Not. 1844
Rosellinia aquila (Fr.) Ces. & De Not. 1844
Rosellinia subiculata (Schwein.) Sacc. 1882
Rosellinia sp.
Genus: Rosenscheldia Speg. 1885 accepted as Botryosphaeria Ces. & De Not., (1863)
Rosenscheldia horridula Doidge 1921
Ru
Genus: Russula Pers. 1796
Russula cyanoxantha (Schaeff.) Fr. 1863
Russula integra (L.) Fr. 1838
Russula pectinata Fr. 1838,
Russula rubra (Lam.) Fr. 1838
See also
List of bacteria of South Africa
List of Oomycetes of South Africa
List of slime moulds of South Africa
List of fungi of South Africa
List of fungi of South Africa – A
List of fungi of South Africa – B
List of fungi of South Africa – C
List of fungi of South Africa – D
List of fungi of South Africa – E
List of fungi of South Africa – F
List of fungi of South Africa – G
List of fungi of South Africa – H
List of fungi of South Africa – I
List of fungi of South Africa – J
List of fungi of South Africa – K
List of fungi of South Africa – L
List of fungi of South Africa – M
List of fungi of South Africa – N
List of fungi of South Africa – O
List of fungi of South Africa – P
List of fungi of South Africa – Q
List of fungi of South Africa – R
List of fungi of South Africa – S
List of fungi of South Africa – T
List of fungi of South Africa – U
List of fungi of South Africa – V
List of fungi of South Africa – W
List of fungi of South Africa – X
List of fungi of South Africa – Y
List of fungi of South Africa – Z
References
Sources
Further reading
South African biodiversity lists
South Africa | List of fungi of South Africa – R | [
"Biology"
] | 4,739 | [
"Fungi",
"Lists of fungi"
] |
69,175,991 | https://en.wikipedia.org/wiki/List%20of%20fungi%20of%20South%20Africa%20%E2%80%93%20I | This is an alphabetical list of fungal taxa as recorded from South Africa. Currently accepted names have been appended.
Ic
Genus: Icmadophila Trevis. 1852 (lichen)
Icmadophila ericetorum (L.) Zahlbr. 1895
Il
Genus: Ileodictyon Tul. & C. Tul. 1844
Ileodictyon cibarium Tul. & C. Tul. 1844
Im
Genus: Imbricaria (Schreb.) Michx. 1803 accepted as Anaptychia Körb., (1848)
Imbricaria hottentottum (Ach.) Schwend. 1863 accepted as Xanthoparmelia hottentotta (Ach.) A. Thell, Feuerer, Elix & Kärnefelt, (2006)
In
Genus: Inocybe (Fr.) Fr. 1863
Inocybe microspora J.E. Lange 1917 accepted as Inocybe glabripes Ricken, (1915)
Ir
Genus: Irene Theiss., Syd. & P. Syd. 1917, accepted as Asteridiella McAlpine, (1897)
Irene atra (Doidge) Doidge (1920), accepted as Asteridiella atra (Doidge) Hansf., (1961)
Irene calostroma (Desm.) Höhn. (1918), accepted as Appendiculella calostroma (Desm.) Höhn.,(1919)
Irene ditricha (Kalchbr. & Cooke) Doidge, (1920)
Irene ekebergiae Doidge (1941), accepted as Asteridiella ekebergiae (Doidge) Hansf., (1961)
Irene glabra (Berk. & M.A. Curtis) Doidge (1920), accepted as Asteridiella glabra (Berk. & M.A. Curtis) Hansf., (1961)
Irene gloriosa (Doidge) Doidge (1920), accepted as Appendiculella natalensis (Doidge) Hansf., (1961)
Irene heudeloti (Gaillard) Doidge (1920),accepted as Irenina heudeloti (Gaillard) F. Stevens, (1927)
Irene implicata Doidge (1924), accepted as Asteridiella implicata (Doidge) Hansf., (1961)
Irene inermis (Kalchbr. & Cooke) Theiss. & P. Syd. (1917), accepted as Asteridiella inermis (Kalchbr. & Cooke) Hansf., (1961)
Irene natalensis (Doidge) Doidge (1920), accepted as Appendiculella natalensis (Doidge) Hansf., (1961)
Irene natalensis var. conferta (Doidge) F. Stevens (1927), accepted as Appendiculella natalensis (Doidge) Hansf., (1961)
Irene natalensis var. laxa (Doidge) F. Stevens (1927), accepted as Appendiculella natalensis (Doidge) Hansf., (1961)
Irene nuxiae Syd. (1928), accepted as Asteridiella nuxiae (Syd.) Hansf., (1961)
Irene peddieae Doidge (1927), accepted as Asteridiella peddieae (Doidge) Hansf., (1961)
Irene peglerae (Doidge) Doidge (1920), accepted as Asteridiella peglerae (Doidge) Hansf., (1961)
Irene podocarpi (Doidge) Doidge (1920), accepted as Asteridiella podocarpi (Doidge) Hansf., (1961)
Irene puiggarii (Speg.) Doidge (1920)
Irene rinoreae Doidge (1922), accepted as Irenina rinoreae (Doidge) F. Stevens, (1927)
Irene scabra (Doidge) Doidge (1920), accepted as Asteridiella scabra (Doidge) Hansf., (1961)
Irene speciosa (Doidge) Doidge (1920), accepted as Appendiculella speciosa (Doidge) Hansf., (1961)
Irene strophanthi (Doidge) Doidge (1920), accepted as Asteridiella strophanthi (Doidge) Hansf., (1961)
Irene zeyheri Doidge (1922), accepted as Irenina zeyheri (Doidge) F. Stevens, (1927)
Genus: Irenina F. Stevens 1927 accepted as Appendiculella Höhn., (1919)
Irenina atra (Doidge) F. Stevens 1927 accepted as Asteridiella atra (Doidge) Hansf., (1961)
Irenina ditricha (Kalchbr. & Cooke) F. Stevens 1927
Irenina glabra (Berk. & M.A. Curtis) F. Stevens 1927 accepted as Asteridiella glabra (Berk. & M.A. Curtis) Hansf., (1961)
Irenina implicata (Doidge) F. Stevens 1927 accepted as Asteridiella implicata (Doidge) Hansf., (1961)
Irenina heudeloti (Gaillard) F. Stevens 1927
Irenina rinoreae (Doidge) F. Stevens 1927
Irenina scabra (Doidge) F. Stevens 1927 accepted as Asteridiella scabra (Doidge) Hansf., (1961)
Irenina strophanthi (Doidge) F. Stevens 1927 accepted as Asteridiella strophanthi (Doidge) Hansf., (1961)
Irenina zeyheri (Doidge) F. Stevens 1927
Genus: Irenopsis F. Stevens 1927
Irenopsis bosciae (Doidge) F. Stevens 1927
Irenopsis claviculata (Doidge) F. Stevens 1927
Irenopsis comata (Doidge) F. Stevens 1927
Irenopsis zehneriae (Van der Byl) F. Stevens 1927
Genus: Irpex Fr. 1825
Irpex africanus Van der Byl 1934
Irpex deformis Schrad. ex Fr. 1828 accepted as Schizopora paradoxa (Schrad.) Donk, (1967)
Irpex flavus Klotzsch 1833 accepted as Flavodon flavus (Klotzsch) Ryvarden, (1973)
Irpex fuscoviolaceus (Ehrenb.) Fr. [as fusco-violaceus] 1828, accepted as Trichaptum fuscoviolaceum (Ehrenb.) Ryvarden [as fusco-violaceus],(1972)
Irpex grossus Kalchbr. 1881
Irpex lacteus (Fr.) Fr. 1828
Irpex modestus Berk. ex Cooke 1891 accepted as Pseudolagarobasidium modestum (Berk. ex Cooke) Nakasone & D.L. Lindner, (2012)
Irpex obliquus (Schrad.) Fr. 1828 accepted as Schizopora paradoxa (Schrad.) Donk, (1967)
Irpex tabacinus Berk. & M.A. Curtis ex Fr. 1851, accepted as Hymenochaete odontoides S.H. He & Y.C. Dai, (2012)
Irpex vellereus Berk. & Broome 1873
Is
Genus: Isaria Pers. 1794
Isaria coralloidea Kalchbr. & Cooke 1880
Isaria psychidae Pole-Evans 1912
Isaria sp.
Genus: Isariopsis Fresen. 1863 accepted as Ramularia Unger, Exanth. (1833)
Isariopsis fuckelii (Thüm.) du Plessis 1942
Isariopsis griseola Sacc. 1878 accepted as Pseudocercospora griseola (Sacc.) Crous & U. Braun, (2006)
Genus: Isidium Ach. 1794 accepted as Pertusaria DC., in Lamarck & de Candolle, (1805)
Isidium tabulare Ach.*
Genus: Isipinga Doidge 1921 accepted as Asterina Lév., (1845)
Isipinga areolata Doidge 1921 accepted as Symphaster areolata (Doidge) Arx, (1962)
Isipinga contorta (Doidge) Doidge 1921 accepted as Asterinella contorta (Doidge) Hansf., (1946)
Genus: Isothea Fr. 1849
Isothea rhytismoides Fr. 1849
It
Genus: Itajahya Möller 1895
Itajahya galericulata Möller 1895
Genus: Ithyphallus Gray 1821 accepted as Mutinus Fr., (1849)
Ithyphallus aurantiacus (Mont.) E. Fisch. 1888
Ithyphallus campanulatus Schlecht. (sic) possibly (Berk.) Sacc. 1888 accepted as Battarrea phalloides (Dicks.) Pers., (1801)
See also
List of bacteria of South Africa
List of Oomycetes of South Africa
List of slime moulds of South Africa
List of fungi of South Africa
List of fungi of South Africa – A
List of fungi of South Africa – B
List of fungi of South Africa – C
List of fungi of South Africa – D
List of fungi of South Africa – E
List of fungi of South Africa – F
List of fungi of South Africa – G
List of fungi of South Africa – H
List of fungi of South Africa – I
List of fungi of South Africa – J
List of fungi of South Africa – K
List of fungi of South Africa – L
List of fungi of South Africa – M
List of fungi of South Africa – N
List of fungi of South Africa – O
List of fungi of South Africa – P
List of fungi of South Africa – Q
List of fungi of South Africa – R
List of fungi of South Africa – S
List of fungi of South Africa – T
List of fungi of South Africa – U
List of fungi of South Africa – V
List of fungi of South Africa – W
List of fungi of South Africa – X
List of fungi of South Africa – Y
List of fungi of South Africa – Z
References
Sources
Further reading
South African biodiversity lists
South Africa | List of fungi of South Africa – I | [
"Biology"
] | 2,237 | [
"Fungi",
"Lists of fungi"
] |
69,176,580 | https://en.wikipedia.org/wiki/Yttrium%20iodide | Yttrium iodide is a binary inorganic compound, a salt of yttrium and hydroiodic acid with the formula . The compound forms colorless crystals, soluble in water.
Synthesis
1. Heating yttrium and iodine in an inert atmosphere:
2Y + 3I2 -> 2YI3
2. Heating yttrium oxide with ammonium iodide:
Y2O3 + 6NH4I -> 2YI3 + 6NH3 + 3H2O
It can also be obtained by reacting yttrium oxide or yttrium hydroxide with hydroiodic acid.
Physical properties
Yttrium iodide forms colorless flaky crystals. The crystal structure is that of the structure type.
It dissolves well in water and ethanol. Does not dissolve in diethyl ether.
It also occurs as a tri- and hexahydrate.
Applications
A precursor for YBCO superconducting materials in a lower temperature preparation.
References
Yttrium compounds
Iodides
Metal halides | Yttrium iodide | [
"Chemistry"
] | 213 | [
"Inorganic compounds",
"Metal halides",
"Salts"
] |
70,662,021 | https://en.wikipedia.org/wiki/Mavacamten | Mavacamten, sold under the brand name Camzyos, is a medication used to treat obstructive hypertrophic cardiomyopathy.
Mavacamten is a small-molecule allosteric and cardiac myosin inhibitor. It was developed by MyoKardia, a subsidiary of Bristol Myers Squibb. In clinical studies, mavacamten has demonstrated significant efficacy in reducing cardiac muscle contractility by targeting the sarcomere hypercontractility that is one of the characteristics of hypertrophic cardiomyopathy and inhibits excessive myosin actin cross-bridge formation, shifting the overall myosin population towards an energy-sparing, recruitable, super-relaxed state.
Mavacamten was approved for medical use in the United States in April 2022. The US Food and Drug Administration (FDA) considers it to be a first-in-class medication.
Medical uses
Mavacamten is indicated for the treatment of adults with symptomatic New York Heart Association class II-III obstructive hypertrophic cardiomyopathy to improve functional capacity and symptoms.
Adverse effects
The US prescribing information for mavacamten contains a boxed warning regarding heart failure. Mavacamten reduces the left ventricular ejection fraction (LVEF) and can cause heart failure due to systolic dysfunction.
History
Mavacamten was granted orphan drug designation by the US Food and Drug Administration (FDA).
Society and culture
Legal status
On 26 April 2023, the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) adopted a positive opinion, recommending the granting of a marketing authorization for the medicinal product Camzyos, intended for the treatment of symptomatic obstructive hypertrophic cardiomyopathy (oHCM). The applicant for this medicinal product is Bristol-Myers Squibb Pharma EEIG. In June 2023, the European Commission approved Mavacamten.
Mavacamten is approved for use in the US, Canada, Australia, South Korea, Singapore, Switzerland, Brazil and Macau.
Names
Mavacamten is the international nonproprietary name (INN).
References
Further reading
External links
Amines
Benzene derivatives
Benzyl compounds
Drugs developed by Bristol Myers Squibb
Orphan drugs
Pyrimidines
Pyrimidones
Cardiac myosin inhibitors | Mavacamten | [
"Chemistry"
] | 501 | [
"Amines",
"Bases (chemistry)",
"Functional groups"
] |
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