id int64 39 79M | url stringlengths 31 227 | text stringlengths 6 334k | source stringlengths 1 150 ⌀ | categories listlengths 1 6 | token_count int64 3 71.8k | subcategories listlengths 0 30 |
|---|---|---|---|---|---|---|
74,040,345 | https://en.wikipedia.org/wiki/International%20day%20against%20violence%20and%20bullying%20at%20school%20including%20cyberbullying | The International Day Against Violence and Bullying at School, including Cyberbullying is a UN Educational, Scientific and Cultural Organization (UNESCO) holiday celebrated every year on the first Thursday of November.
This International Day was designated by the member states of UNESCO in 2019 and it was first held in November 2020.
According to UNICEF, one in three young people in 30 countries have been a victim of online bullying (2019 poll) and half of students aged 13 to 15 experience peer violence around school (2018 report).
In 67 countries, corporal punishment is still allowed in schools.
The UNESCO International day remind people that violence in schools violates the right of children and adolescents to education, health and well-being. The aim is to call on the international community, civil society (including parents, pupils and teachers), the tech industry, the education community and the education authorities to take part in the fight against violence and bullying at school.
Celebration
2022
The 2022 edition emphasized the role of teachers in making schools safe places for everyone. An International seminar on the role of teachers in preventing and addressing school violence and bullying called "Not on my watch" was organized at UNESCO headquarters.
2023
The theme was "No place for fear: Ending school violence for better mental health and learning."
See also
School violence
Bullying
Cyberbullying
Bullying in teaching
Anti-bullying legislation
References
United Nations days
School violence
Harassment and bullying
Cyberbullying
UNESCO
November observances | International day against violence and bullying at school including cyberbullying | [
"Biology"
] | 292 | [
"Harassment and bullying",
"Behavior",
"Aggression"
] |
74,040,596 | https://en.wikipedia.org/wiki/Meagan%20Wolfe | Meagan Wolfe is an American election official who has served as the administrator of the Wisconsin Elections Commission since 2018. Prior to this role, she was the Commission's deputy administrator and IT director. She has been the target of election conspiracies and partisan complaints since the 2020 United States presidential election, and Republicans in the Wisconsin Legislature and on the Wisconsin Elections Commission are attempting to remove her from office.
Career
Wolfe was born in Waukesha County, Wisconsin, and raised in Waupaca County. In 2009, she founded a rental real estate company that refurbishes historic buildings in Madison, Wisconsin. In 2011, Wolfe joined the staff of the Wisconsin Government Accountability Board as the voter outreach coordinator. She was responsible for keeping the public informed on the state's election processes and voter identification laws. She stayed on when the board was reestablished as the Wisconsin Elections Commission (WEC). She later became an elections IT project manager and IT director. In 2017, Wolfe became deputy administrator of the commission.
In February 2018, the commission, comprising three Republicans and three Democrats, voted for Wolfe to serve as the interim administrator, succeeding Michael Haas. She was appointed interim administrator March 2, 2018, and was unanimously confirmed by the Wisconsin State Senate on May 15, 2019, for a term ending June 30, 2023.
Removal efforts (2020–present)
Following the 2020 United States presidential election in Wisconsin, she faced calls by Republican members of the Wisconsin Legislature to resign. In response to the criticism, the Wisconsin Business Leaders for Democracy Coalition, a bipartisan group expressed support for Wolfe.
When her term came to an end in June 2023, Wolfe remained in office due to the recent Wisconsin Supreme Court ruling that the expiration of an appointed term did not alone warrant removal from office when no replacement had been confirmed. Republican officials then believed they could remove her through the Senate confirmation process, by renominating her and having the Senate reject her nomination. Republican members of the commission attempted to vote for her renomination, but the Democratic members of the commission abstained from the vote, preventing a majority vote for renomination.
The Wisconsin Senate deemed she had been renominated and that they would move to consider the nomination. The state attorney general, Josh Kaul, then wrote to the Senate telling them that there was no appointment and any Senate vote on the matter would be invalid. The Senate moved forward with their process and voted along party lines to disapprove of her reappointment. Following the advice of the attorney general, Wolfe remained in office and said of the Senate vote: "My position as administrator is, of course, subject to removal by the majority vote of the commission at any time. In the meantime, unless a final determination of a court says otherwise, I will continue to serve as the administrator of the (Wisconsin Elections Commission)." Kaul ultimately launched a lawsuit to clarify the legality of Wolfe's status, holding to the precedent of the recent Wisconsin Supreme Court decision in State ex rel. Kaul v. Prehn, where the court held that an official could remain in their post beyond the expiration of their term until a successor was properly nominated and confirmed.
Subsequently, a number of Republican state representatives, led by Janel Brandtjen, began circulating a resolution to attempt to remove her through the impeachment process. In early October, however, two conservative former Wisconsin Supreme Court justices spoke out against the use of impeachment for such partisan political purposes, and Republicans in the legislature then appeared to back away from some of their impeachment threats. Subsequently, in the attorney general's case on this matter, Republican filings indicated that they acknowledged that their vote to reject Wolfe was "symbolic" and that Wolfe was "lawfully holding over" in her role.
Those pushing for her ouster, however, were not dissuaded by the arguments of the conservative former Wisconsin Supreme Court justices about the serious nature of impeachment. Brandtjen called for her impeachment articles to move forward into the committee process, and her calls were echoed by former justice Michael Gableman, who had run an unsuccessful two-year investigation to find fraud in the 2020 election. In the first days of November 2023, a right wing PAC, calling itself "Wisconsin Elections Committee", began airing advertisements threatening the Wisconsin Assembly speaker, Robin Vos, with a recall and primary challenge if he did not move Brandtjen's impeachment resolution forward. Vos—who had barely survived a 2022 primary challenge—caved to their demands just hours after the ad campaign was announced, and assigned the articles of impeachment to the Assembly Committee on Government Accountability and Oversight.
Within days of that announcement, former U.S. president Donald Trump also weighed in, sharing a copy of Brandtjen's press release to his social media followers on Truth Social. On November 9, 2023, Brandtjen attempted to bring her impeachment resolution to the Assembly floor, but the attempted was ruled out-of-order by speaker pro tempore Kevin David Petersen. Around that time, Vos commented, "I think we need to move forward and talk about the issues that matter to most Wisconsinites and that is not, for most Wisconsinites, obsessing about Meagan Wolfe."
The ad campaign against Wolfe proceeded anyway, and around the same time, Vos' appointee to the Wisconsin Elections Commission, Don Millis, came out with a strong defense of Wolfe in a Milwaukee Journal Sentinel op-ed, saying, "grifters are spending more than $100,000 to peddle lies about Elections Commission Administrator Meagan Wolfe". He went on to explain the legal and historical reality of the charges against Wolfe:
Millis further chastised the Journal Sentinel and other Milwaukee media for not fact-checking the ads.
Nevertheless, right wing agitation continued calling for Wolfe's termination. The advertising and direct mail campaign did continue in southeast Wisconsin urging impeachment, and Vos received more pressure from his legislature colleagues, including Senate president Chris Kapenga. This campaign culminated in a recall campaign launched against Vos in January 2024.
Dane County circuit judge Ann Peacock ruled in favor of Wolfe on January 10, 2024, saying that the Wisconsin Elections Commission had not officially renominated her and therefore the state Senate's vote rejecting her renomination had no legal weight. Senate Republicans had requested that the judge order the Wisconsin Elections Commission to officially nominate a replacement, but the judge also rejected that, finding no legal obligation for the Commission to submit a timely nomination of a successor.
Wolfe continued to be a target of right wing conspiracy theories going into the 2024 presidential election. In an April 2024 radio interview, Trump again named Wolfe as a key scapegoat for his defeat in 2020, saying: "I couldn't understand how we lost that election because, you know, I love the state, I have so many friends in the state... It never made sense to me. Now we find out why. She should be gone." He also said that if she were not removed, she "will try to steal another election." He also continued trying to influence Republican Assembly speaker Robin Vos to find some way to get rid her. Following Trump's comments, and due to an increase in threats, Governor Tony Evers approved additional security for Wolfe.
References
External links
Living people
Year of birth missing (living people)
Place of birth missing (living people)
People from Waukesha County, Wisconsin
People from Waupaca County, Wisconsin
Women in Wisconsin politics
People in information technology
21st-century American women civil servants | Meagan Wolfe | [
"Technology"
] | 1,562 | [
"People in information technology",
"Information technology"
] |
74,040,959 | https://en.wikipedia.org/wiki/Henry%20W.%20Woltman%20Award | The Henry Woltman Award is an annual medical prize in neurology, first awarded to Leonard Robin Carney in 1966 by the Mayo Clinic, Rochester, Minnesota. It is named for neurologist Henry Woltman with the purpose of honouring a “fellow or resident in the neurological sciences who demonstrates superior ability and performance in the field of clinical neurology in regard to careful observation of clinical phenomena, sympathetic care of patients and initiative in teaching of clinical neurology.”
References
Awards established in 1966
Neurology
Medicine awards | Henry W. Woltman Award | [
"Technology"
] | 110 | [
"Science and technology awards",
"Science award stubs",
"Medicine awards"
] |
74,041,037 | https://en.wikipedia.org/wiki/Radium%20azide | Radium azide is an inorganic compound of radium and nitrogen with the chemical formula .
Synthesis
Radium azide can be prepared by dissolving radium carbonate in aqueous hydrazoic acid and evaporating the resulting solution.
Physical properties
Radium azide forms white crystalline solid.
Chemical properties
The compound decomposes when heated to 180–250 °C:
References
Azides
Radium compounds | Radium azide | [
"Chemistry"
] | 83 | [
"Explosive chemicals",
"Azides"
] |
74,041,250 | https://en.wikipedia.org/wiki/Bean%20prize | The Bean prize, also known as the William B. Bean Student Research Award and named for William Bennett Bean, is awarded annually to medical students by the American Osler Society (AOS) for research in history of medicine and humanities.
Background
The Bean prize is named for William Bennett Bean, who was a resident physician under Sir William Osler. Bean became the first president of the American Osler Society, who created the award for medical students.
References
External links
History of medicine
Medicine awards | Bean prize | [
"Technology"
] | 99 | [
"Science and technology awards",
"Medicine awards"
] |
74,041,415 | https://en.wikipedia.org/wiki/Sterimol%20parameter | A sterimol parameter is a set of vectors which describes the steric occupancy of a molecule. First developed by Verloop in the 1970s. Sterimol parameters found extensive application in quantitative structure-activity relationship (QSAR) studies for drug discovery. Introduction of Sterimol parameters into organic synthesis was pioneered by the Sigman research group in the 2010s. Benefiting from the multi-dimensional values that they carry, sterimol parameters give more accurate predictions for the enantioselectivity of asymmetric catalytic reactions than its counterparts, especially in cases when structurally complicated ligands are used.
Definition
Sterimol parameters are built upon the Corey-Pauling-Koltun atomic models, which take into consideration the Van der Waals radii of each atom in the molecule. Unlike most other steric parameters such as A-value, Taft parameters and Tolman cone angle, which group all the spatial information into a single cumulative value, Sterimol parameters consist of three sub-parameters: one length parameter (L), and two width parameters (B1, B5). The three parameters add together to profile the 3-dimensional spatial information of a molecule.
In order to define the Sterimol parameters of a molecule, an axis needs to be defined at first. Since Sterimol parameters are usually applied for describing the bulkiness of a certain substituent which is attached to the substrate, the default choice of the axis is the one that passes through the atoms which link the substrate and substituent together. This axis is defined as the X-axis.
Once the X-axis has been defined, the Sterimol parameters can be assigned. Take the 1,2-dimethylpropyl group as an example (Figure 1). The length parameter (L) refers to the farthest extension of the substituents in the direction parallel to the X axis (shown in Figure 1, left). The width parameters can be assigned from the point of view which is perpendicular to the X axis. The width parameter B1 refers to the minimal profile width of the substituents on the linking atom from the X axis, while parameter B5 refers to the maximal width from the same axis (shown in Figure 1, right).
Sterimol B2–B4 parameters were initially used for obtaining the maximal width. However, in his second generation Sterimol approach, Verloop pointed out that due to their directional dependence on Sterimol B1, discrepancies arose when computing those three parameters in cases where B1 can point to multiple directions. Since Sterimol B2 and B3 hardly contributed significantly to any regression functions obtained, and Sterimol B4 was practically equal to B5, the parameters B2–B4 were omitted.
Sterimol B1 parameter demonstrates the steric effects imposed by branching at the linking atom of a substituent. The more branches the linking atom bears, the larger Sterimol B1 value the substituent has. On the other hand, Sterimol B5 parameter is more susceptible to the steric effects of the substituent's terminus. In general, Sterimol B1 represents vicinal steric effects of the substituent, while Sterimol B5 represents remote steric effects.
Several open-source programs have already included the feature of calculating Sterimol parameters, such as Morfeus, Kallisto, and dbstep.
Application in asymmetric catalysis
In the 2010s, machine learning emerged as a powerful tool for guiding catalyst discovery. More specifically, machine learning models such as multivariate linear regression have been applied to study the linear free energy relationships (LFERs) in catalytic asymmetric organic reactions. These relationships describe the effects that ligand substituents have on reaction outcomes, namely enantioselectivity, and can be extrapolated to predict the performance of ligands outside the known dataset. However, machine learning approaches require well-defined molecular descriptors for the steric and electronic properties of ligands in order to make accurate predictions. Sterimol parameters emerged as a good candidate for quantifying the steric environment induced by ligands.
In Matthew Sigman's seminal work published in 2012, Sterimol parameters were implemented in asymmetric catalysis for the first time in the analysis of an asymmetric Nozaki-Hiyama-Kishi reaction (Figure 2). In initial ligand screening the team found that the steric hindrance of the ester substituent on the oxazoline-proline-based ligand scaffold was pertinent to the overall enantioselectivity of the reaction. When attempting to use the Charton modification of the Taft's parameters for probing the LFERs, they observed breaks in linearity with respect to several "isopropyl-like" substituents with large Charton values (Figure 3, left). However, this break did not exist when the Sterimol B1 parameter was used instead. All of the substituents studied demonstrated good linear correlation between their Sterimol B1 value and the reaction enantioselectivity (Figure 3, right).
Sigman attributed the superiority of Sterimol B1 in this prediction over Charton values to the inherent limitations of the experimentally based Charton values. He noted that the Charton model assumes that the substituent can rapidly rotate around the X-axis. However, in the context of asymmetric catalysis, only one conformation of the substituent provides the transition state with lowest energy, which leads to the formation of the major enantiomer. Therefore, Charton values tend to overestimate the steric effects of substituents that are non-symmetrical around the X-axis, because they can only describe the net conformer of a certain substituent. Sterimol parameters, in contrast, are not derived from experimental results, which are sometimes idiosyncratic as a result of distinct mechanisms. By virtue of their origin, namely quantum chemical calculations, Sterimol parameters can more accurately interpret the steric effects of a substituent in its static form. Sterimol B1, in particular, can approximate the steric repulsive effect of the exact conformer with the lowest energy. Table 1 demonstrates the differences of the two parameters. For example, while they have the same Sterimol B1 values, the Charton value of the isopropyl-like CHPr2 substituent is significantly larger than that of i-Pr due to overestimation. This explains why better correlation was obtained with Sterimol B1.
To date, the Sigman lab has applied Sterimol parameters in the analysis of several catalytic asymmetric reactions. Sterimol parameters are also utilized by chemists worldwide to improve the enantioselectivity for various catalytic reactions, such as conjugative addition, Tsuji-Trost reaction, C–H activation, cyclopropanation, etc.
Weighted sterimol parameters
Following Sigman's work, the Paton lab developed a revised form of Sterimol parameters in 2019. Termed "weighted Sterimol" (wSterimol), this new depiction of Sterimol parameters considers the influence of conformational effects. Paton stated that enantioselectivity is a macroscopic observable, and multiple conformations should not be overlooked when generating descriptor values, especially for substituents with greater conformational flexibility. With this in mind, Paton designed the python-based program "wSterimol", which combines conformation search with Sterimol parameter calculation. In a fully automated fashion, the program performs conformer generation, geometry optimization, filtering and Sterimol computation. Finally, the program outputs weighted Sterimol values wB1, wB5 and wL, which are generalized based on Boltzmann distribution. This user-friendly program has been applied in the studies of several asymmetric catalytic systems
References
Stereochemistry
Physical organic chemistry | Sterimol parameter | [
"Physics",
"Chemistry"
] | 1,675 | [
"Stereochemistry",
"Space",
"nan",
"Physical organic chemistry",
"Spacetime"
] |
74,041,891 | https://en.wikipedia.org/wiki/Selective%20eating | Selective eating, also known as picky eating, is a variety of behaviors whereby people are highly selective in what they eat and do not eat. Selective eating is common in younger children and can also sometimes be seen in adults.
There is no generally accepted definition of selective eating, which can make it difficult to study this behavior. Selective eating can be conceptualized as two separate constructs: picky eating and food neophobia. Picky eaters reject both novel and familiar food whereas food neophobic people are thought to reject unfamiliar foods specifically. Selective eating can be associated with rejecting mixed or lumpy foods. It can also be associated with sensory sensitivity.
Estimates of the prevalence of selective eating vary due to measuring instruments, age of sample, or population sample. However, studies suggest that feeding problems occur in about 80% of children with intellectual and development disabilities, and in about 25-45% of typically developing children. Consequently, a proportion of selective eaters continue into adulthood with similar eating patterns as during childhood.
Selective eating in children is a common concern for parents, as it may lead to nutritional inadequacies and mealtime struggles. While many cases of selective eating tend to diminish with age, some individuals continue to exhibit discerning eating habits into adulthood, which can impact their overall health and well-being.
There is debate as to whether selective eating represents an eating disorder or is related to eating disorders. Some extreme forms of selective eating are recognized as psychiatric disorders such as avoidant/restrictive food intake disorder (ARFID), or proposed psychological disorders such as orthorexia nervosa.
Causes and contributing factors
The etiology of selective eating is not well understood but can be broadly explained through nature and nurture. Nature typically refers to genetic predispositions, which play a significant role in the development of selective eating behaviors. The ability to taste certain bitter thiourea compounds, such as 6-n-propylthiouracil (PROP) and phenylthiocarbamide (PTC), is genetically determined. PROP tasters tend to have more food dislikes due to heightened sensitivity to bitter compounds. As a result, they’re at higher risk of developing selective eating patterns. Additionally, several studies provide evidence that food neophobia is highly heritable. A study conducted on over 5000 twin pairs and their parents found a neophobia heritability estimate of 0.78, although about 25% of phenotypic variation was accounted for by environmental factors.
Environmental influences during early life also shape selective eating behaviors. The impact of early experiences with flavor, both in utero and via breastfeeding, plays a crucial role in shaping food preferences later in life. Fetuses are exposed to the flavors present in the mother's diet through the amniotic fluid, leading to heightened preferences for those flavors postnatally. Breastfeeding further influences flavor preferences, as flavors from the mother's diet are transmitted through breast milk. Infants exposed to various flavors through breastfeeding demonstrate increased acceptance of those flavors during weaning. During weaning, the timing and variety of foods introduced influence children's readiness to consume new and varied foods. Parenting style and feeding practices further influence children's food behaviors. Cole et al’s (2017) systematic review cites several studies indicating that negative, non-responsive feeding styles are positively associated with selective eating. Across these studies, high warmth authoritative parenting was reported as being the most beneficial for implementing healthy eating habits. Lastly, the food environment at home, encompassing food availability and exposure to novel foods, significantly influences children’s food preferences and behaviors. Children exposed to a greater variety of foods at home tend to consume more fruits and vegetables. However, it’s important to note that some families will struggle to provide their children with varied healthy food options due to socioeconomic restrictions or food insecurity.
Ultimately, various factors interact to shape each child’s eating behaviours and food preferences. Early experiences including exposure to flavors in utero and via breastmilk, interact with genetic differences in flavor perception to establish food preferences. Nurture elements such as exposure to different tastes and parental feeding practices can modify feeding behaviors. Conversely, a child's innate preferences, behaviors, and temperament can influence nurture elements. Research indicates that children who are sensitive to sensory stimuli may be less likely to model their parents' fruit and vegetable consumption, highlighting the bidirectional nature of picky eating. Further research is needed to fully understand the intricate interactions between these factors and their relation to selective eating.
Implications
Family conflict
Selective eating often causes conflict within the family. Studies have reported impairment in family functioning with both moderate and severe selective eating. Parents of selective eaters commonly report that their children consume a restricted range of foods; require food prepared in particular ways; express strong preferences and aversions towards food and throw tantrums when these are denied. This often leads parents to providing meals for their children that are different from the rest of the family. Selective eating may also be a significant source of concern for parents as it may prompt physician visits and potentially spark conflict between parents regarding how to manage their child's eating behavior.
Physical health
Selective eating is characterised by a restricted diet. Restricted diet can have a concerning impact on growth and development. Studies show it is associated with poor physical health through nutritional deficiencies including low intakes of iron and zinc as these are associated with low intakes of fruit, vegetables, and meat. Also, lower intakes of vitamin C, vitamin E, folate, and fiber has been noted, which may lead to a weakened immune response and digestive problems.
Studies have shown mixed findings regarding the relationship between selective eating and being at risk of being underweight or overweight. A 1997 study of a group of selective eaters (aged 4–14) found that "a significant minority has poor growth or weight gain." Yet, this observation could be attributed to their broadened interpretation of selective eating and the inclusion of much younger children. There remains little evidence for a consistent effect of being a selective eater on growth trajectories. Further research is needed to investigate the effects of selective eating on brain development and metabolism.
Psychosocial symptoms
Selective eating is linked to eating psychopathology and psychosocial dysfunction. This includes both internalizing (e.g., anxiety, depression) and externalizing (e.g., attention deficit hyperactivity disorder) psychopathology. Both moderate and severe levels of selective eating are associated with psychopathological symptoms, and the severity of these symptoms tends to worsen with more severe selective eating.
Selective eaters tend to show social avoidance, although it's unclear whether this is a result of selective eating behavior or simply reflects a primary social skills deficit. The extent of social avoidance varies but one case study of a 9-year-old boy identifies the impact of selective eating specifically. He missed lunch at school so found it difficult to make friends. It affected how long he could stay at his friend's house. It prevented the whole family from going on visits and this family tension was exacerbated as his dad would get cross and go off with his brothers.
Diagnosis
Assessment of selective eating varies due to the lack of universal definition. Considering the complex etiology of selective eating, assessment (and later treatment) ideally should be carried out by an interdisciplinary team of professionals.
One of the most common ways of measuring selective eating is using scales. Selective eating can be measured with a list heuristic, where the number of foods that the person rejects on a standard list is counted. When investigating selective eating in children, parental report tends to be the most common tool of measurement. Two commonly used questionnaires include the Child Eating Behavior Questionnaire Food Fussiness subscale (CEBQ FF) and the Food Neophobia Scale (FNS). These questionnaires have undergone validation against weight-for-age-z score or child body mass index z-score (BMIz), with greater selective eating being negatively correlated with BMIz or weight-for-age z-score. However, a limitation of such scales is that they either rely on individuals to self-identify as selective eaters or rely on parental report which may be biased. Parents may struggle to accurately gauge the extent to which their child's eating habits differ from typical behavior for children, or they may find that their perception of their child's eating behavior is influenced by their own concerns regarding eating and feeding habits.
Therefore, it can be helpful to validate selective eating scales against observational measures. There are a range of ways to conduct observational assessments of selective eating behavior. One study tested participants individually and told them that they were participating in a study of the relation between mood and taste perception. They were presented with various types of cookies and asked to rate them along various dimensions and told to eat as many as they wanted as fresh cookies would be baked for each participant. Following the taste test, participants completed a packet of surveys including dietary restraint scales as well as distractor scales (e.g. mood measures). Each of the plates was weighed before and after participant arrival to provide an unobtrusive measure of total caloric intake.
Extreme forms of selective eating have been recognized as eating disorders, mainly avoidant/restrictive food intake disorder (ARFID). These should be assessed through diagnosis. The DSM-5 includes a 'feeding and eating disorders' section and covers several diagnoses that may be related to selective eating.
See also
Dietary conservatism, the prolonged reluctance to eat novel foods, a foraging strategy observed in animals
References
Human behavior | Selective eating | [
"Biology"
] | 1,966 | [
"Behavior",
"Human behavior"
] |
74,042,213 | https://en.wikipedia.org/wiki/Baobab-K | The Baobab-K is a Polish automated mine-laying system mounted on the Jelcz 8×8 truck chassis.
History
The Baobab-K's research and development phase began in 2017.
On 14 June 2023, Polish deputy prime minister Mariusz Błaszczak granted approval for delivery contracts of the Baobab-K mine-laying vehicles and their corresponding mines by Huta Stalowa Wola. During the approval process, it was disclosed that one of the contracts entails the supply of 24 Baobab-K mine-laying vehicles for a total value of PLN 510 million. The delivery of the vehicles is scheduled to take place between 2026 and 2028.
Additionally, the contracts involve the purchase of mines and cassettes amounting to PLN 566 million.
Specifications
The vehicle operates with a two-person crew and has a maximum capacity of up to 600 mines. It is capable of traversing mine-laying operations at speeds ranging from 5 to 25 km/h, covering an area of approximately 1,800 meters in length and 180 meters in width.
References
Minelayers
Mine warfare
Military equipment introduced in the 2020s | Baobab-K | [
"Engineering"
] | 239 | [
"Military engineering",
"Mine warfare"
] |
74,042,362 | https://en.wikipedia.org/wiki/Miqin%20Zhang | Miqin Zhang is an American materials scientist who is the Kyocera Professor of Materials Science at the University of Washington. Her research considers the development of new biomaterials for medical applications. Her group develops nanoparticles for cancer diagnosis and imaging, biocompatible materials for drug delivery and cell-based biosensors.
Early life and education
Zhang earned her doctorate at the University of California, Berkeley. Her doctoral research considered bioengineering of silicon surfaces for controlled protein adsorption.
Research and career
In 1999, Zhang joined the faculty at the University of Washington, where she was made professor in 2008. She has developed new biomaterials for the diagnosis and detection of disease. Her research focused on three activities; the development of nanoparticles for cancer diagnosis and treatment, the realization of materials to serve as biodegradable scaffolds and the development of cellular biosensors for detecting chemical agents.
Zhang developed novel synthesis strategies for the creation of functionalized nanoparticles. Nanovectors are nanoparticle cores that are surrounded by an agent that targets cells with specific functionality. Zhang designed a nanovector that can target glioma, a form of brain cancer. The Zhang nanovector was based on a superparamagnetic iron oxide core, a polyethylene glycol coating, a chlorotoxin targeting agent and a fluorescent dye. The cyanine-based dye emits infrared light, which can penetrate brain tissue. Her nanoparticles could be traced using both MRI and fluorescence microscopy.
Zhang has also developed nanofibrous matrices from polymeric materials to use in tissue engineering and regenerative medicine. She has also developed hydrogels that can be used for drug delivery.
To detect and identify biological agents, Zhang has developed surface modification techniques to pattern proteins and live cells. She makes use of receptor mediated cell adhesion, a technique which involves immobilizing proteins on electrodes which can be patterned.
Selected publications
References
Year of birth missing (living people)
Living people
American materials scientists
Women materials scientists and engineers
21st-century American scientists
21st-century American women scientists
University of California, Berkeley alumni
University of Washington faculty
20th-century American scientists
20th-century American women scientists | Miqin Zhang | [
"Materials_science",
"Technology"
] | 465 | [
"Women materials scientists and engineers",
"Materials scientists and engineers",
"Women in science and technology"
] |
74,042,388 | https://en.wikipedia.org/wiki/Samarium%28III%29%20phosphate | Samarium(III) phosphate is an inorganic compound, with the chemical formula of SmPO4. It is one of the phosphates of samarium.
Preparation
Samarium(III) phosphate can be obtained by reacting sodium metaphosphate with any soluble samarium(III) salt:
Samarium(III) phosphate can also be obtained by reacting phosphoric acid and samarium(III) chloride.
Properties
Samarium(III) phosphate reacts with sodium fluoride at 750 °C to form
Na2SmF2PO4. Samarium(III) phosphate forms crystals of the monoclinic crystal system, with space group P21/n, and lattice parameters a = 0.6669 nm, b = 0.6868 nm, c = 0.6351 nm, β = 103.92 °, Z = 4.
References
Phosphates
Samarium(III) compounds | Samarium(III) phosphate | [
"Chemistry"
] | 185 | [
"Phosphates",
"Salts"
] |
74,042,790 | https://en.wikipedia.org/wiki/2023%20MOVEit%20data%20breach | A wave of cyberattacks and data breaches began in June 2023 after a vulnerability was discovered in MOVEit, a managed file transfer software. Thousands of organisations and almost 100 million individuals were affected.
Background
MOVEit is a managed file transfer software developed by Ipswitch, Inc., a subsidiary of Progress Software. A vulnerability in the software allows attackers to steal files from organizations through SQL injection on public-facing servers. The transfers are facilitated through a custom web shell identified as LemurLoot. Disguised as ASP.NET files used legitimately by MOVEit, LemurLoot can steal Microsoft Azure Storage Blob information.
Timeline
According to cybersecurity firm Mandiant, the MOVEit vulnerability began being used on May 27, 2023.
On May 31 Progress Software released a patch for the vulnerability and stated the vulnerability “could lead to escalated privileges and potential unauthorized access to the environment”.
On June 3, the Government of Nova Scotia estimated that as many as 100,000 present and past employees were impacted by the breach.
On June 5, various organizations in the United Kingdom, including the BBC, British Airways, Boots, Aer Lingus, and payroll service Zellis were breached.
On June 6, Cl0p claimed responsibility for the attack on its site on the dark web. Cl0p claimed that the data stole from governments had been deleted (this was later disproved).
On June 12, Ernst & Young, Transport for London, and Ofcom separately announced that they had been affected, with Ofcom announcing that personal and confidential information was downloaded.
On June 15, CNN reported that the United States Department of Energy was among multiple United States government organizations affected by the MOVEit vulnerability. The following day, it was reported that the Louisiana Office of Motor Vehicles and Oregon Driver and Motor Vehicle Services were hit, affecting millions of residents.
Responsibility
According to the Cybersecurity and Infrastructure Security Agency and the Federal Bureau of Investigation, the breaches are being conducted by Cl0p, a Russian-affiliated cyber gang.
Impact
A running total maintained by cybersecurity company Emsisoft showed that more than 2,500 organizations were known to have been impacted as at October 25, 2023 with more than 80 percent of those organizations being US-based.
Response
Cybersecurity and Infrastructure Security Agency (CISA), CrowdStrike, Mandiant, Microsoft, Huntress and Rapid7 have assisted with incident response and ongoing investigations. Cyber industry experts have credited the MOVEit team for its response and handling of the incident by quickly providing patches In general, patches for the flaw where rapidly used.
References
2023 in computing
Progress Software
Computer security exploits
Cyberattacks
Data breaches
Hacking in the 2020s
Software bugs | 2023 MOVEit data breach | [
"Technology"
] | 561 | [
"Computer security exploits"
] |
74,043,675 | https://en.wikipedia.org/wiki/Pan-African%20Payment%20and%20Settlement%20System | The Pan-African Payment and Settlement System (PAPSS) is a Pan-African real-time gross settlement (RTGS) infrastructure for cross-border payments in distinct local currencies. It was publicly launched on January 13, 2022 by the African Union (AU) and the African Export-Import Bank (Afreximbank) to compliment trading under the African Continental Free Trade Area (AfCFTA) with further future planned rollout in the Caribbean region by end of 2024.
History of PAPSS
PAPSS was first mentioned on the 7 July 2019 at the 12th Extraordinary Session of The African Union Assembly in Niamey, Niger to support the launch of the operational phase of AfCFTA. It started as a pilot project among the 6 countries in the West African Monetary Zone (WAMZ) before it became publicly available. In 2023 several nations of the Caribbean Community began to implement a pilot framework for using the Pan-African Payment and Settlement System to facilitate trade between the Caribbean and Africa. The move coincided with the Afreximbank agreeing to designate the Caribbean region as a diaspora-related sixth region of Africa and opened an office in the Caribbean island of Barbados. PAPSS is slated to be rolled out among Caribbean countries which have already signed the agreement with Afreximbank, and is slated to come on stream in Q4, 2024.
How it works
Here is a simplified overview of how PAPSS works
A company issues a payment instrument to their local bank or payment service provider
The payment instruction is sent to PAPSS through the country's central bank and routes it to the beneficiary bank account
PAPSS performs all validation checks on payment instruction before it sends it forwards it to the beneficiary's central bank and eventually to the local bank account
PAPSS sends credit or debit settlement instruction to the Central Bank of the originator and the Central Bank of the beneficiary. The Central Banks settle the transaction in hard currency, using Afreximbank as the settlement agent.
Once the cross-border net settlement is complete, the beneficiary receives the funds in their local currency.
On a daily basis, PAPSS settles the balance of all of the transactions among individual African currencies, netting them out prior to midnight. Central Banks then resolve the remaining difference. The payments and settlement process starts again from net zero the next day.
Central Banks
These are the banks enrolled in PAPSS (December 2024)
Bank of Ghana
Central Bank of Nigeria
Central Bank of Liberia
Central Bank of the Republic of Guinea
Bank of Sierra Leone
Reserve Bank of Zimbabwe
Central Bank of Djibouti
Bank of Zambia
Central Bank of Kenya
Central Bank of The Gambia
Central Bank of Tunisia
Central Bank of Egypt
Central Bank of the Comoros
Reserve Bank of Malawi
National Bank of Rwanda
See also
Cross-Border Inter-Bank Payments System (CIPS)
Indian Financial System Code (IFSC)
Fedwire
Mir (payment system)
Structured Financial Messaging System (SFMS)
List of financial regulatory authorities by country
Society for Worldwide Interbank Financial Telecommunications (Swift)
SWIFT ban against Russian banks
Real-time gross settlement
References
External link
Payment systems
Real-time gross settlement
Economy of the African Union
African Union
African Continental Free Trade Agreement | Pan-African Payment and Settlement System | [
"Technology"
] | 667 | [
"Real-time gross settlement"
] |
74,045,465 | https://en.wikipedia.org/wiki/Javier%20Borda | Javier Borda (born 1951 in Bermeo, Biscay) is an industrial engineer, researcher-teacher of industrial systems with many scientific publications, and a Spanish businessman. He is president of Sisteplant, a multi-national company of industrial systems engineering.
Education and professional career
He holds a Doctorate in Industrial Engineering from the Escuela Técnica Superior de Ingenieros Industriales de Bilbao (ETSII), a Master's Degree in Quantitative Models and an MBA from the Escuela Superior de Técnica Empresarial (ESTE) of the University of Deusto (1974-1976). He obtained his doctorate from the University of the Basque Country in 1988 with a thesis entitled "Architecture and CIM Computer Models in Thermoplastic Injection Moulding".
He was a professor at the University of Deusto (1984-2001), teaching Production Management; at the Aula Aeronautica of the Escuela Superior de Ingenieros Industriales de Bilbao (2005-8), teaching Advanced Production Systems for Aerospace and Defence; and at the King Juan Carlos University, teaching Advanced Maintenance, Repair and Overhaul (MRO) Systems for Defence in 2005.
AAs a scientist of industrial production, he advocates the social function of business. Throughout his career, he has helped companies large and small to develop their industrial models.
In 1984, he founded Sisteplant, a multinational company dedicated to the provision of technological solutions for the optimisation of production and maintenance processes in industry. He was Managing Director of Datalde (1984-1994) and later Chief Executive Officer. Between 1991 and 2000 he was a member of the now defunct IFIP (International Federation for Information Processing), part of UNESCO.
He received the Automoción-ACICAE Award from the Automotive Cluster of the Basque Country (2023) for his commitment to the Basque automotive sector.
Publications
He is the author of six books as well as scientific and popular articles, focusing on the relationship between man and machine and the risks of digitalisation, robotics and the use of artificial intelligence.
In La Fábrica del futuro. Humana, inteligente, tecnológica y digital (The Factory of the Future. Human, Intelligent, Technological and Digital), published in 2016, he further explores the theory that without advanced industry, the future is practically non-existent. For the author, ICT is merely an "interpreter" and we need to place ourselves above artificial intelligence.
In Hombre y Tecnología: 4.0 y más (Man and Technology: 4.0 and Beyond), he examines the role of the human being in the Fourth Industrial Revolution and is sceptical about robotized industry if it is not matched by a higher technological level of the people who operate it. For Borda, the four basic pillars of the factories of the future are strategy, technology, people and habitability, and he advocates the creation of "laboratory factories" with management models that allow "producing with quality while experimenting to do better tomorrow".
As a scientist, he has participated in international congresses and several research projects. It's worth mentioning what he's done:
Books
La Fábrica del Futuro. Humana, inteligente, tecnológica y digital (The Factory of the Future. Human, intelligent, technological and digital). Sisteplant Publishers, 2016.
Hombre y Tecnología: 4.0 y más (Man and Technology: 4.0 and beyond). Sisteplant Publishers, 2018.
El pensamiento filosófico y científico en la industria del futuro: El Hombre Nuevo (Philosophical and scientific thinking in the industry of the future: The New Man) Sisteplant Publishers, 2019.
Tecnología para el Mantenimiento Científico en las Plantas Cibernéticas (Technology for Scientific Maintenance in Cybernetic Plants). Editorial Sisteplant, 2022.
Papers
Borda, J. (2000). Evolución en la Problematica de Mantenimiento y Cambios Necesarios En Los Sistemas de Gestión. DYNA, 75(1), 17-22.
Borda, J. (2006). Launching the aeronautical sector. Qualitas hodie: Excellence, sustainable development and innovation, (116), 62-63.
Borda, J., Delegado, C., & Datalde, D. G. D. (1986). Concepts of systems theory. Application to the firm in a new technology environment. Bulletin of Economic Studies, 41, 563.
Borda, J. (1990). Technology, organisational change and competitiveness. Economic Studies Bulletin, 45, 255.
Popular articles
La sostenibilidad en la fábrica del futuro (Sustainability in the factory of the future) Cinco Días.
VVAA: La Nueva Economía de la Defensa en un Nuevo Orden Mundial (The New Defence Economy in a New World Order) Ministerio de Defensa 2017.
¿Industrializar la fabricación de micro y nanoproductos? (Industrialising the manufacture of micro and nanoproducts?) Revista del Colegio Oficial de Ingenieros Industriales de Madrid, 2011.
Industria: ¿Proteccionismo o precaución? (Industry: Protectionism or precaution?) El economista.
References
Industrial engineers
Academic staff of the University of Deusto
Academic staff of the University of the Basque Country
Spanish businesspeople
Systems scientists
1951 births
Living people | Javier Borda | [
"Engineering"
] | 1,183 | [
"Industrial engineers",
"Industrial engineering"
] |
74,046,335 | https://en.wikipedia.org/wiki/Obi%20Peter%20Adigwe | Obi Peter Adigwe is a Nigerian pharmacist and a doctor of pharmaceutical policy. He was appointed the Director General of the National Institute for Pharmaceutical Research and Development (NIPRD) with effect from 10 August 2018 by the former president of the Federal Republic of Nigeria, Muhammadu Buhari. Before his appointment as NIPRD boss, he was the Executive Secretary of the Pharmaceutical Manufacturers Group of the Manufacturers' Association of Nigeria and holds a Doctor of Pharmaceutical Policy at the University of Leeds, United Kingdom.
Dr. Adigwe was the pioneer Head of the Health Policy Research and Development (HPRD) Unit at the National Assembly (Nigeria), where he formulated research and development strategies in Health Policy with a view to developing an Evidence-Based approach to Legislation and Policy formulation in Nigeria. He also developed innovative and contextual capacity-building modules for Healthcare Professionals, as well as coordinated research that contributed to Health System strengthening. He has a significant number of peer-reviewed publications including the first Knowledge Attitudes and Perceptions study on Ebola in Nigeria, as well as a seminal paper on Rational Use of Medicines. While in the United Kingdom, he was the lead author of the article “Rewrite the Script for Non-medical Prescribing” which contributed to prescribing policy reforms in the Parliament of the United Kingdom.
Throughout his career, Adigwe has pioneered a significant number of innovative research and developmental projects. He led teams that secured various high-profile grants including a Clinical Trials Grant from the ECOWAS, an API Grant from African Export–Import Bank, a Drug Development Mega Grant from Tertiary Education Trust Fund and a European Union / Government of Bulgaria Grant supporting Local Production of Vaccines in the Nigerian setting. Based on the NIPRD study led by Dr Adigwe, the European Union EU announced the award of an €18m grant to Nigeria, as a catalyst for vaccines research.
Dr. Obi Peter Adigwe has headed and served on numerous Committees and Expert Working Groups at both national and international levels, including the D8, United Nations, World Health Organisation [WHO], The African Union and ECOWAS. Dr. Adigwe was conferred with Nigeria's highest Productivity Award by the President of Nigeria in recognition of his hard work, productivity and excellence in National Developmental Initiatives. Adigwe is a Fellow of the Nigerian Academy of Pharmacy, as well as of the West African Institute of Public Health.
Education
Obi Adigwe attended University of Jos, Jos, obtaining a bachelor's degree in pharmacy in 2000. He proceeded to the University of Edinburgh, UK and obtained MSc in Global Health and Public Policy in 2008 and a Doctorate degree (PhD) in Pharmaceutical Policy from the University of Leeds, UK, in 2012.
Career
Obi Adigwe started his career as a pharmacist at the National Assembly (Nigeria)'s Pharmacy Department, FCT, Abuja Nigeria, in 2005 and remained there till 2007. He proceeded to become the Senior Project Officer at the Pharmacy Department Unit at University of Leeds, United Kingdom, from 2010 to 2012.
From 2012 to 2015, he was the head of the Health Policy Research and Development Unit at the National Assembly (Nigeria) (NASS), FCT, Abuja, Nigeria, where he formulated research and development strategies across multiple policy areas and also authored write-ups to disseminate findings from research projects.
On 14 June 2022, Adigwe was reappointed as the Director General of National Institute for Pharmaceutical Research and Development (NIPRD).
Adigwe has mentored over 80 PhD and MSc candidates, and 100 Pharmacists. Adigwe has more than 82 scientific presentations. He chaired and contributed to the COVID-19 pandemic response, by providing an internationally acclaimed analysis that was recognized by the Nigerian Government and positioned the country on the Madagascan Covid Organics preparation.
References
Living people
Nigerian pharmacists
Pharmaceutical industry
Year of birth missing (living people) | Obi Peter Adigwe | [
"Chemistry",
"Biology"
] | 814 | [
"Pharmaceutical industry",
"Pharmacology",
"Life sciences industry"
] |
74,046,482 | https://en.wikipedia.org/wiki/List%20of%20Oceanian%20countries%20by%20life%20expectancy | This is a list of Oceanian countries by life expectancy at birth.
United Nations (2023)
Estimation of the analytical agency of the UN.
UN: Estimate of life expectancy for various ages in 2023
UN: Change of life expectancy from 2019 to 2023
World Bank Group (2022)
Estimation of the World Bank Group for 2022. The data is filtered according to the list of countries in Oceania. The values in the World Bank Group tables are rounded. All calculations are based on raw data, so due to the nuances of rounding, in some places illusory inconsistencies of indicators arose, with a size of 0.01 year.
In 2014, some of the world's leading countries had a local peak in life expectancy, so this year is chosen for comparison with 2019 and 2022.
WHO (2019)
Estimation of the World Health Organization for 2019.
Charts
See also
References
Life expectancy
Oceania | List of Oceanian countries by life expectancy | [
"Biology"
] | 192 | [
"Senescence",
"Life expectancy"
] |
74,046,549 | https://en.wikipedia.org/wiki/Lithium%20periodate | Lithium periodate is an inorganic compound of lithium, iodine, and oxygen with the chemical formula .
Physical properties
The compound forms a white powder. It also forms hydrates and is soluble in water.
References
Periodates
Lithium compounds | Lithium periodate | [
"Chemistry"
] | 47 | [
"Periodates",
"Lithium salts",
"Oxidizing agents",
"Salts"
] |
74,046,551 | https://en.wikipedia.org/wiki/Redmi%2012 | The Redmi 12 and Redmi 12 5G are Android-based smartphones marketed as part of the Redmi series by a sub-brand of Xiaomi Inc with the same name. The 4G model was announced on June 15, 2023 and the 5G model was announced on August 1, 2023.
In China, the Redmi 12 5G is also sold as the Redmi Note 12R. Later, the Redmi 12 5G was released under the POCO brand as the POCO M6 Pro 5G with different back designs and colors. Also, several months later the POCO M6 Pro 5G was released in China as the Redmi 12R.
Design
The front and back are made of Gorilla Glass, while the frame is made of plastic.
On the bottom of smartphones, there is a USB-C port, speaker, and microphone. On the top, there is 3.5mm audio jack and infrared blaster. On the left, there is a hybrid Dual SIM tray (SIM1 + SIM 2 or SIM1 + microSD). On the right, there is the volume rocker and the power button with a mounted fingerprint scanner.
The Redmi 12 and Redmi 12 5G on the global market are available in 3 colors: Midnight Black, Sky Blue, and Polar Silver. On the Indian market, these models are available in the same colors under other names: Jade Black, Pastel Blue, and Polar Silver respectively.
The Redmi 12 5G on the Chinese market is available in Star Rock Gray and Ice Porcelain White.
The Redmi Note 12R is available in 3 colors: Midnight Black, Time Blue, and Sky Fantasy (Silver).
The Redmi 12R is available in Obsidian Black and Smoke Green. Also, the POCO M6 Pro 5G has the same colors but under other names: Power Black and Forest Green respectively.
Specifications
Hardware
Chipset
The Redmi 12 uses the same octa-core MediaTek Helio G88 CPU as the Redmi 10 with the Mali-G52 MC2 GPU.
On the other hand, the Redmi 12 5G/Note 12R and Redmi 12R/POCO M6 Pro 5G are the first smartphones that feature the Qualcomm Snapdragon 4 Gen 2 with 5G support and the Adreno 613 GPU.
Camera
The Redmi 12 has a triple rear camera with a 50 MP, wide camera + 8 MP, ultrawide camera + 2 MP, macro camera, and a 8 MP front camera.
The Redmi 12 5G/Note 12R and Redmi 12R/POCO M6 Pro 5G have a dual rear camera with 50 MP, wide camera + 2 MP, depth camera. Additionally, the global version of the Redmi 12 5G, Redmi 12R, and Redmi Note 12R have 5 MP, front camera while the Indian version of Redmi 12 5G and POCO M6 Pro 5G have 8 MP, front camera.
All models' rear and front cameras can record video in 1080p@30fps.
Display
The smartphones have a 6.79-inch (172 mm) IPS LCD display at FHD+ (2460 × 1080 px, ~396 ppi) resolution, 90 Hz refresh rate and a punch hole in upper center.
Battery
The models have a non-removable battery with 5000 mAh capacity and 18W fast charging support.
Memory
The Redmi 12, 12 5G, and Note 12R are sold in 4/128, 6/128, 8/128, and 8/256 GB, the Redmi 12R is sold in 4/128 GB, and the POCO M6 Pro 5G is sold in 4/64, 4/128 and 6/128 GB.
The Redmi 12 has an eMMC 5.1 storage type, while the other models feature a UFS 2.2 storage type. Also, all models have LPDDR4X RAM type and microSD support up to 1 TB.
Software
The Redmi models were released with MIUI 14, while the POCO M6 Pro 5G was released with MIUI 14 for POCO. Both ROMs are based on Android 13. Later, all models were updated to HyperOS 2, which is based on Android 15.
References
External links
Android (operating system) devices
12
Mobile phones with multiple rear cameras
Mobile phones with infrared transmitter
Mobile phones introduced in 2023 | Redmi 12 | [
"Technology"
] | 921 | [
"Crossover devices",
"Phablets"
] |
74,051,029 | https://en.wikipedia.org/wiki/Eastern%20esotericism | Eastern esotericism is a term utilized by various scholars to describe a broad range of religious beliefs and practices originating from the Eastern world, characterized by esoteric, secretive, or occult elements. The classification of Eastern esotericism presents challenges, as it is influenced by varying geographical and cultural definitions of "Eastern" and "Western" contexts, particularly in relation to Islamic nations. The delineation of esotericism itself can vary among scholars, with some arguing that the concept is predominantly rooted in Western traditions. This perspective raises important questions regarding the applicability of a Western framework to non-Western practices, potentially leading to classifications that may not accurately reflect the complexities of these traditions. Conversely, other scholars propose a more globalized viewpoint, suggesting that comparable systems of secret knowledge and mystical practices exist across different cultures and warrant examination within a unified framework.
Despite these ongoing debates, the concept of Eastern esotericism has been adopted by many scholars as a relevant category for investigating the nuanced dimensions of spiritual life in various Eastern traditions. This includes elements found in Hinduism and Buddhism, where secret teachings, initiatory rites, and mystical experiences are significant. Additionally, Eastern esotericism encompasses a variety of, ethnic religions and syncretic systems that integrate indigenous beliefs with other spiritual influences, thereby broadening the scope of study in this area. Overall, the term serves as a foundation for exploring the diverse and intricate landscape of esoteric thought and practice across the Eastern world.
Concept demarcation
Marco Pasi points out that the Western concept of esotericism emerged not in an academic context, but due to religionism in the 19th century, when the controversial distinction between Eastern and Western esotericism was first made. Initially, this dichotomy emerged in the 1880s: according to Julian Strube, French occultists accepted the authenticity of what they called "l'ésotérisme occidental" ("western esotericism") while rejecting the "false Eastern esotericism" of the Theosophical Society. There was also in 1890 a conflict within the Theosophical Society itself between William Quan Judge, who advocated for Western occultism, and Annie Besant, who advocated for the Eastern variant. According to Pasi: "It is therefore primarily as a reaction to an idea of "Eastern esotericism" that the idea of "Western esotericism" could develop." However, according to Strube, this is not enough to define these signifiers, as a complex network of exchanges occurred between various Eastern and Western cultures, and borders changed historically, politically, and ideologically. Therefore he defends the conceptualization of global esotericism. Different understandings of esotericism were produced globally, mainly through exchanges throughout the 19th century. Thus, scholars of religion often use the term "esoteric" to categorize practices that reserve "certain kinds of salvific knowledge for a selected elite of initiated disciples," according to Wouter Hanegraaff's description.
Depending on the definitions, most Western esotericism could be considered Eastern. Western esotericism has been deeply influenced by non-Western traditions, and vice versa, especially in contemporary times. This categorization into two hemispheres was of more internal importance to the rhetoric of esoteric movements than to academic discourse.
For example, in Neoplatonism, and then again from the Renaissance on, an exoticism was associated with the origin of the major teachings, as of the origin of Platonic philosophy in Ancient Egypt or of ancient knowledge to the "Chaldaic mysteries," the mystical and occult representing "Eastern wisdom". Thus, Iamblichus, for example, referred to the Chaldean Oracles as transmitting "ancient Assyrian doctrines," and Plethon attributed their origin to Zoroaster. Such a concept in the Western imagination has been called "Platonic Orientalism" by scholars.
The perspective can also vary according to the occultists' agenda, one example being Italian neo-pagan esoteric movements in the 20th century that, inspired by the "traditionalist Roman school", considered Christianity a "degeneration from the East" that would have nothing in common with the Western esoteric tradition, which they considered paganism. The esoteric "rhetoric of a hidden truth" also hinged on the exotic, forming in the imagination a "mystical East," and when Egypt ceased to be attractive in its exoticism, the pole of the "mystical East" shifted to India and beyond, as the "true abode of ancient wisdom."
Academically, it has come to be considered in some more recent studies of esotericism, such as those of Gordan Djurdjevic and Henrik Bogdan, that there are close equivalents of Western esotericism in Asian cultures, suggesting an Indian, Chinese, or Far Eastern "esotericism" in general. A large part of esotericism scholars argues that it is preferable to analyze it in a transcultural and globalized way, according to each nationality or cultural region, focusing on the interactions of the concept in a more specific local or cross-cultural way beyond "Western" and "Eastern", or also relatively and openly. With this, the differences of each system are taken into account, despite some similarities in matters of the occult and the possibility of a secrecy system, as in secret knowledge, elitism, theories about spirit and matter, a supposed universal knowledge, and hierarchical rites of passage.
Henrik Bodgan and Gordan Djurdjevic consider "Eastern esotericism" to be present alongside Western elements of Aleister Crowley's magick system, and Djurdjevic recognizes the spread of the study of Eastern esotericism as an important legacy of Crowley. Jeffrey J. Kripal uses the term "Asian esotericism" in his study of Tantra, and Olga Saraogi advocates the possibility of an "asiacentric" analysis of esotericism. Georgiana Hedesan and Tim Hudbøg consider that "Western" and "Eastern" can be used as relative designations, but that they are limiting, with specific localities such as European, Indian, and African being preferred.
Others, like Helmut Zander, say that it is not because there is a well-defined technical concept of "Western esotericism" that there must exist an "Eastern esotericism", "Northern esotericism", or "Southern esotericism". There are proposals for a category open to "global esotericism" or "open esotericism," considering that rigid definitions of esotericism do not apply to all cultures and at all times. Thus, Zander writes, for example, as Jan Assmann theorizes, that it is part of the history of Western religion since antiquity; a tension that is reflected in the semantics of public versus private, open versus secret; but proposes that defining "secret" as a possibility rather than a requirement may allow consideration of esotericism in other non-Western traditions. It is not because a system originates in a Western context and is assimilated by colonized cultures that it remains Western, according to scholars such as Egil Asprem, Julian Strube, Keith Cantú, and Liana Saif, who argue for the autonomy of the local agency in creating innovations on the material.
Antoine Faivre and Wouter Hanegraaff defined esotericism as a specifically Western phenomenon, intending to overcome the religionist paradigm of an "esoteric core" common to all religions or a perennial universalist truth. The term "Western" served to delimit esotericism not as a transhistorical essence of all religion, but highlighting it as a set particular to a historical current. Thus, in this sense, Asprem indicates that the term is as much opposed to "universal esotericism" as to geographically localized esotericisms: "The term is opposed not so much to "Eastern" (or "Northern" or "Southern") esotericism as to universal esotericism." Hanegraaff writes that the creation of a category of "Oriental esotericism" would have to be different from Faivre's inaugural definition: "It follows that if one were to conceive of an "Oriental esotericism" (whatever the definition), that would necessarily be something else." Karl Baier writes that the current comparative study of religions has more refined techniques and does not necessarily adopt a religionist agenda and that then the use of the comparative category "esotericism" is not precluded. According to Baier, the Faivre/Hanegraaff paradigm excludes any non-European agency, as if non-Western cultures could not actively contribute to or develop esotericism: "Yet research on modern yoga and in other fields of cross-cultural interactions between Near and Middle Eastern, South Asian and East Asian cultures, as well as African cultures and European or American esoteric currents, reveal globally entangled developments." Julian Strube also believes that esotericism was formed in a globally interwoven way and that Hanegraaff's current conceptual perspective repeats religionism and excludes non-Western developmental contexts.
According to Hanegraaff, Carl Jung was a major contributor in spreading the cross-cultural study of esotericism in a more global perspective, analyzing the Western occult tradition and seeking parallels with Eastern systems. He perceived two mentalities, a more rational conscious one and an unconscious one, and claimed that in studying thoughts of Western and Eastern cultures he found the same shared substratum of the collective unconscious, which could be studied historically, but which, according to Hanegraaff, corresponds to the reservoir of traditionally "rejected knowledge."
According to Marco Pasi, "if esotericism is not a universal phenomenon, but is specifically rooted in and limited to Western culture, then it should not be necessary to label it as 'Western'. The moment it is labeled as 'Western', it also becomes possible to assume that there are other 'non-Western' forms of esotericism." There is criticism, however, of the misapplication of esotericism to other contexts, such as that it has been used in religionist assumptions and has overflowed into other generalizing Western categories about non-Western cultures, such as shamanism. For instance, studies such as Marcel Griaule's have been criticized for inducing the creation of mystifications considered "esoteric" in a non-Western context: that of the African religion of the Dogon, in what he called "la parole claire" - the deepest level of secret knowledge. There are nuances to the analysis: the esoteric stems from notions of secrecy, although not every dimension of secrecy refers to the esoteric, such as shameful matters, and not every secret is initiatory. Apter suggests, in turn, that secret knowledge is not necessarily fixed in certain cultures, such as the esoteric of the Yoruba and Dogon, and is perhaps always fluid and changeable according to contexts. As for the East, European perspectives on religion have been influenced by trends in Orientalism, which in turn have influenced the attribution of esotericism into "esoteric Orientalism," often demeaning Eastern religious beliefs and practices as superstitious or irrational.
Esotericism, as a broad term in its ethical perspective, is a comparative category to worldviews or connected practices that are widespread in diverse cultures throughout history and around the world. However, in a second strict meaning, emically, it originates from strict historical currents in the interaction of different cultures, or as a Euro-American phenomenon, from Western esotericism.
However, it has become common to attribute Eastern esotericism to doctrines of Hinduism, as in the Tantras and Yoga; to branches of Buddhism found in India, China, Japan, Tibet, Korea, and Vietnam, calling it "esoteric Buddhism"; and to other non-sectarian practices, such as those of the Baul. One finds, for example, the analogical thinking system of external and internal correspondences (as macrocosm and microcosm) in Indian rituals and theories comparable to statements of Western esoteric systems, as well as practices of magic, alchemy, and divination. Richard Kaczynski points out that while it is not his intention "to conflate Eastern Tantra and Western Magic, although I find it heuristically useful to refer to both as forms of esotericism," he employs the "second-order (ethical) term that is applied by scholars to the subject under much more consistent scrutiny than it is used as a self-referential (emic) designation," with a reason for comparison just as Aleister Crowley did with regard to the similarities he saw between Eastern and Western traditions.
Cantú uses "Western" and "Eastern" for convenience, and writes that it is a notion that is implied from the division of "Western", yet vague: "My point is that postulating a Western esotericism also implies the postulation of an "Eastern esotericism," which even if not declared or not analyzed, creates a category that has no intrinsic existence apart from various disconnected movements, whether Islamic, Hindu, Buddhist, Taoist, or non-sectarian (e.g., the Fakir) who could justifiably be said to be participating in a type of esotericism." He proposes a more neutral and global approach to esotericism, considering the local, native, and trans-local dimensions, in which a system becomes diffuse and varied in multiple places as it moves away from its point of origin. With the flow from trans-local to local (called "localization"), assimilation of Western concepts can occur from the internal agency of members of colonized communities. It cannot, therefore, be said that the system loses its authenticity, even though there has been an influence in a return pollination movement from Europe to Asia, with the appropriation of new esoteric categories, as in Yoga. Thus, it indicates the existence of two dimensions: "translocal esotericism" and "local esotericism," from which the affirmation of authenticity and inauthenticity is locally constructed.
In any case, manifestations of esotericism are the result of a dynamic bricolage of ideas, coming from diverse places, sources, and cultures, but also among the practice's own discursive communities. This makes categorizations inconsistent and boundaries shift on the part of the very agents who analyze the phenomenon. Examples that bring difficulty are the use of the occult in modern Japan, in new religious movements such as the Oomoto, or the doctrine of Ruhollah Khomeini in Iran - both situations being asserted to be emic esoteric innovations avowedly opposed to Western thought; or else the emergence of new emic demarcations of esotericism by Eastern scholars, as by Masaharu Anesaki (1873-1949).
Against the historicist paradigm of considering esotericism as a discursive strategy exclusive to the epistemology of the West, Egil Asprem defends in a typological approach the usefulness of comparing non-Western esotericisms to verify if esotericism is a transcultural category that may have emerged independently in several places:
Looking beyond the particular to see how similar "thought forms," secret organizations, or claims to higher knowledge operate in contexts beyond the West (...), may even help uncover selection pressures and environmental factors that can help explain the emergence of esotericism in the "West" and formulate more precise and theoretically refined definitions. (...) What can the cognitive science of religion tell us about the generation and transmission of "thought forms" or "cognitive styles" considered unique to Western esotericism? Is there a dynamic of "convergent cultural evolution" that sheds light on the formation of "esoteric-type" groups, movements, discourses, experiences, or idea structures?
Mesopotamia
There was a well-established concept of secrecy in Mesopotamia, associated with reserved knowledge. One finds, for example, the words AD-ḪAL = pirištu (in Sumerian and Akkadian, respectively, meaning "secret"), Nì-DUL = katimtu ("hidden," "covered"), and (KI)-ÙRU = niṣirtu ("guarded"). According to the traditions of Mesopotamian religions, there were gods entrusted with the divine secrets and they passed on the knowledge to royalty individuals, who in turn passed it on to classes of scholars and scribes. Guardians of heavenly and earthly secrets included Enki/Ea, god of wisdom, Nabu, Inanna, as well as Ninshubur (who kept the secrets of the sky god Anu) and Nuska (who kept those of Enlil, king of the gods).
The Mesopotamians developed an esoteric scribal tradition, such as the collections of their rites or the practice of haruspice. Their tablets were copied and transmitted "from the man who knows to the man who knows." The arts of writing and writings were a secret, as stated in a Sumerian text from the 2nd millennium B.C. There are lexical lists from the 4th millennium B.C. taken as "secret knowledge of the sage," and giving a taxonomy of the world of esoteric tenor. There are instances of the use of cryptography as well: in the middle of the 3rd millennium B.C., an esoteric orthography called UD-GAL-NUN was invented and used for secret mythological narratives. From the end of the second millennium BCE onward, clauses are found on the tablets identifying the content as secret knowledge that could be passed from one knower only to another knower, and that infringing this by passing it on to an uninitiated was a "taboo of the gods."
Knowledge of exorcism and divination was also monopolized. The exorcist's function is nominally designated as secret (niṣirtu) in the Exorcist's Manual (1st millennium BCE), about which one reads is the (KAR 44:30-31): "totality of the sources of wisdom, the secrets of the art of incantations, the sources of the planes of heaven and earth, the secrets of the Lalgar (abyss) and the non-canonical incantations (ahû)". "Sources" is a metaphor for the underground water of Abzu, associated with the god of wisdom Enki, as an analogy of the origin of esoteric knowledge.
The monarch took on a social role as a medium of prophecy, often through the metaphor of the "sacred marriage". There is no evidence that the narratives about Sumerian rites of hierogamy (marriage between a deity and the king) or theogamy (marriage between gods) occurred literally, or that a sexual ritual consecration of the monarch with a priestess in sacred prostitution was necessarily performed. They were, however, a rhetorical way of showing that there was close communication between the monarch and the "secrets of the gods." The non-verbal erotic connection symbolically allowed for verbal mediation and this legitimized their power, in connection with the divine world. In Inanna's oracle to Ibal-pi-el II (r. c. 1779-1765 BCE), the goddess introduces herself as follows: "The secrets of the gods are before me. Because the invocation of my name is always in your mouth, I will reveal to you, one by one, the secrets of the gods." It is likely an element of secrecy in Inanna's cult since her information was passed on orally to a small elite. Her love songs are not explicitly said to be esoteric, but this may also be suggested by the scarcity of written material. The existing cultic texts, however, although said to be "secret," do not constitute evidence in themselves that there were secret cults or ritual initiations into mysteries to the Goddess of Love, but take on a connotative function of expressing divine approval in the royal ideology.
The Babylonian myths did not undergo any changes until after 900 B.C., and the scholars produced specialized and esoteric knowledge on top of the existing one. In Babylonian, the priest Berossus reported to the Greeks that the Babylonian myths were allegories, and that from their dissemination in a Hellenistic context the notion of an ancient legendary wisdom of the Chaldeans was spread, as the "Chaldean science" of astrology. The Mesopotamian thought of Assyrian and Babylonian esotericism was semiological in character, which interpreted the created things in the world as written signs of divine elocutions, which must be examined and deciphered in divination.
The name apkallu was given to legendary cultural heroes, descended from humans, who received divine wisdom and taught the antediluvian sciences. Chief among them was the mythical sage Adapa, reported by Berossus under the name Oannes, and seen as esoteric wisdom by the Greeks. Ashurbanipal boasted claiming that he had grasped "the art of the apkallu Adapa, the esoteric secret of the entire scribal tradition." J. van Dijk suggests that purification rituals may have had an esoteric aspect traced to the mythical sage Adapa and which extended to later local esoteric and Gnostic traditions, such as Mandaeism.
It is probable that the "magoi" Heraclitus referred to were either Persian priests or Babylonian exorcists. The nocturnal healing rituals he described, involving an imaginary trial of witches and sorcerers, with the lighting of a fire and invocations to break the spell of illness, are similar to those described in the Babylonian collection Maqlû.
Zoroastrianism
An esoteric dimension is suggested in the interpretation of Zoroastrian texts, with scholars considering that there was a hierarchy of religious knowledge, as evidenced in some passages that refer to a deep reading dimension. In the article Esoteric trends in Zoroastrianism (1969), Shaul Shaked considers that Sassanid Zoroastrianism, although open, possessed an informal categorization that included the notion of hidden knowledge. He identifies the term rāz (literally "secret") as greater esoteric knowledge, reserved for members and initiated of a higher religious rank. Dan Sheffield also considers, from analysis of the Wizirgerd ï Denïg, that exegesis of the Avesta was guided by the idea that it contained secrets: "Now one must know with the help of intelligence and mind that mysterious utterances abound in the Avesta." He proposes the hypothesis that curiosity for seeking secrets led to the development of Zand (exegesis; literally, "interpretation"), as written in Denkard 6.215: "the dēn has seven walls, and they called the farthest one the sacred word and Zand." A decree from the reign of Khosrow I, however, limited the Zand to closed priestly circles, aiming at preserving moral order and preventing desecration by heretics: "Keep this Yasna secret, but teach the Zand to no one except your offspring." Thus Denkard 6 evidences:
One must be worthy of all the secrets (and) the battles of the gods; then, when a man is worthy, the gods themselves inform them of their secrets and battles, for the gods desire a trustworthy treasurer. The secret of the gods and their battles are not hidden from anyone, for you know that the more people know more, the more powerful the gods will be.
In the poetics of the Yasna, Martin Schwartz identifies the existence of linguistic encryption in the structuring of the verses, as in they recommend themselves "to the knower" and signal a revelatory message with a presence of esotericism.
The main idea that scholars speculate is strongly rooted in the Avestan ritual is that of an opening of an esoteric path, through which priests could meet with Ohrmazd, gaining an early mental vision of the afterlife and the condition of saoshyant. During the sacrificial rite, it is hypothesized that there were ecstatic or esoteric components in which the officiant would also consecrate themselves by an internalization in which they elevated their soul, in celestial ascent. One of the titles of the priest Kartir was Ohrmazd mowbed, which for the Denkard, according to Prods Oktor Skjaervo, was "applied to people who revealed themselves as having the ability to see into the other world (mēnōy-wēnišnīh)." Kartir describes in his inscriptions his vision of the "final destination" according to such a special ritual context, in a deeply esoteric account of an encounter in Paradise with his female double dēn, "in the form of a woman".
James Russell speculates that the Zoroastrians believed in special knowledge about the end of the cosmic battle of Good and Evil, which, in addition to coming from the reading of the Gatha by a specialized class, would also include the employment of mystical techniques by spiritually advanced believers, such as ecstasy by wine or psychotropic substances (supposedly haoma), as well as silent meditation (in Avestan: tušnā-maitiš) and mantric recitations (in Avestan: manthra-).
The recitation of the most important hymn, the Ahuna Vairya, is strongly linked to cosmological components, and implies a secret knowledge held by the priest that possesses it, possibly correlating it to the 21 constellations of the northern part of the sky. These constellations and those of the Zodiac were symbolized equally on the utensils of the ritual table, and a pattern of choreography by the priests indicates positions of the spatial axes and stages celestial movements, in an act to defeat the Evil Spirit.
Henrik Samuel Nyberg and Mary Boyce suggest that a change in the calendar during the Achaemenid period in which four days were now dedicated to the "Creator," supposedly Ahura Mazda, in places previously occupied by other Yazata (deities), may be evidence of a nod by Achaemenid monarchs to the esoteric belief in Zurvanism as the original Being who would preexist the two principles and who possesses a tetradic trait. This underlying design was, however, in covert form, not gaining popular support.
A Judeo-Christian tradition viewed the "Magi of the East" in a positive light, due to the narrative of the Biblical Magi, in which they had contact with the revelation of supernatural secrets. Some other Christians, on the other hand, accused them of an alleged veiling. Contact with the religious knowledge and rites of the Persian priests impressed the Greeks, fostering both a good and a bad perspective in the imagination due to the exoticism. The term "magic" and context of magic in the Greco-Roman world was derived from the Persian word for Zoroastrian "Magi".
There was also an esoteric legacy from the Magi in the interaction between Masdaism and Christianity in the East, as in the Christian transmission to Iranian Zoroastrians. According to this, Christ was presented several times as having already been prophesied by Zoroaster, as being the Saoshyant, what may have been locally associated in speculations about the three sons of Zoroaster and their relations to the "Universal Divine Time" (Zurvan), in a Zurvanic tetrad before the Ohrmazd.
Manichaean doctrines derived many aspects from Zoroastrian terminology and thought, combining and modifying them with Judeo-Christian, Buddhist, and Gnostic ideas within an esoteric framework to explain life and death. Unlike Zoroastrianism, Mani's system regarded matter as an evil principle. According to Götz König, the Zoroastrianists, likely critical of Manichaeism saw in it a heresy of esoteric interpretation that perverted the "true" understanding of the sacred texts. There is a record of accusations against the doctrine of principles elaborated by Mani, and the Manichaean textual technique elaborated a model on the Gatha in which new elements were assigned to the names of the gods.
In the 6th century, the sect of Mazdak arose from the teachings of Zardusht Khorragan and his disciple Mazdak. They expounded a Zoroastrianism with esoteric elements, incorporating a Gnostic vision and light symbolism to advocate a philosophy of love and social reform, as interpreters of Zoroaster's message and the Avesta. Mazdak stated that the "secret sense" (nehani) was necessary knowledge for their faith, probably referring to the esoteric senses of the Avesta.
In the 9th century, the Denkard presented evidence of a hermeneutical interpretation of the Gatha that shared the paradigm of "omnisignificance" according to James Kugel, analogous to the rabbinic traditions of Talmudic commentators, with a search for parallelism between texts and a possible reinterpretation of every word in divine scripture as containing a latent cryptic meaning. The Wizīdagīhā ī Zādspram ("Selections from Zadspram") is also another independent text from the same century within the Zoroastrian tradition, involving medical conceptions, numerology, and astrology to cosmic speculations, in contexts that may denote esoteric meaning.
Azar Kayvan (16th-17th centuries), asserting that the end of the Islamic millennium was near, declared an era with Persian superiority and founded the Abadi order, combining Sufi, gholātī, and Illuminationist ideas with Zoroastrian texts. Followers believed that his new scriptures, Dasatir-i-Asmani, were divinely revealed. The work was composed in an artificial language and accompanied by Persian commentaries, and Kayvān considered that those who were not Zoroastrian abadis did not understand that the Zend-Avesta was the esoteric (ta'vīl) interpretation of the Dasatir.
In the early 20th century, a movement called Ilm-e Kshnoom ("Path of Enlightenment" or "Beatific Knowledge"), founded by Behramshah Nowroji Shroff, was influenced by the Theosophical Society and claimed to possess the esoteric knowledge of Zoroastrianism.
Indian traditions
Linguistically, several Sanskrit terms are considered close to the notion of esoteric: adhyātmika ("spiritual"), alaukika ("unworldly"), alaukika jñāna ("spiritual knowledge"), gupta ("hidden"), gupta sādhana ("secret rituals"), siddha darśana ("hidden perception").
Several scholars use the term "Hindu esotericism" in comparison to the alchemical and hatha elements of Hindu mysticism, connected primarily with Tantrism. There are also culturally Hindu spiritual lineages of direct transmission and initiation, involving a master and a pupil, going back at least to 1500-1000 B.C.. Elizabeth De Michelis considers that, despite parallels in the category of esotericism, esoteric Hindu practices are much more widely accepted and employ elements of the conventional tradition of classical Hinduism, while Western esotericism has the connotation of being a fringe set compared to orthodoxy. The category on a west–east axis appeared during the modern development of Hinduism, with processes of esotericization and cross-influence, for example in Neo-Vedanta and Yoga. According to Richard Kaczynski, "One can generalize that in both Indian and Western esotericism there is a tendency to sublimate the religious quest."
Gordan Djurdevic considers Yoga as analogous to magic in the search for powers (considered sacred), a cultivation of imagination (corresponding to meditation), and containing the principle of eros (search for union). He also points to the category of esotericism according to Antoine Faivre's definitions as a cross-cultural phenomenon and applicable to the Nāth Siddhas, who share the components of the doctrine of correspondences (macrocosm-microcosm), living nature (in the concept of Shakti), transmutation (as the "reversal" of ulṭa sādhana), the practice of concordance (in the ideal of unitive wisdom of diverse traditions), the transmission of knowledge by initiation, and gnosis in their yogic practices. They were also one of the first religious groups in medieval India to make use of the vernacular language rather than Sanskrit to transmit esoteric ideas, but they equally made use of rhetorical strategies in a "secret language," such as employing paradoxes in the poems to indicate a reversal of the ordinary world, in an "upside-down language" (Ulṭabāmsī).
The tantra is considered a sprout of Vedic-Brahmanic and Yogic traditions whose system is mainly characterized by correspondences of macrocosm and microcosm and also by a reintegration of the mundane into the salvational path, such as the ritual employment of sexuality and dualism to achieve non-duality. The erotocentric rites are sometimes referred to as "left hand" (vāmācāra) in Hindu sayings, but not by Buddhists. In Sanskrit literature and the testimony of the practicing tantric, an outer Indian origin is attributed to them. In India, Buddhic tantrism assimilated Hindu gods as symbols, as well as in Japan in syncretism with the Shinto, and in Tibet with the native Bon gods.
Many of its elements are native to India, but it is difficult to know which originate from Vedic doctrines and which from Buddhist doctrines; they likely influenced each other and drew on other non-Hindu sources. It is also difficult to trace, with Shaivist tantras appearing in the 9th and 10th centuries, while Buddhist tantras can be more accurately dated to the level of decades and with more evidence to earlier eras. Thus, what can be asserted is that there were several connections among the Indian traditions, yet each with equally unique developments. In addition to Buddhist and Pancharatran/Shaivist literature, the tantras used the Dharani literature as well as political sources on an ideology of kingship, as seen in the earliest tantric system of Ekākṣara-uṣṇīṣa-cakravartin ("The Universal Emperor of the Buddha's Uṣṇīṣa [assuming the aspect of] a Single Syllable").
The foundational Kulārṇava Tantra text from the 12th century states that the doctrines of the Vedas, Sastras, and Puranas can be revealed, but that those of the Shaivist and Shaktist agamas (i.e., the tantras) must be kept secret.
Tantras considered fundamental are the Guhyasamāja Tantra (compiled in the 5th-6th centuries), Cakrasaṃvara (8th century), Hevajra, Vajravārāhī, Kālacakra, among other Anuttara Yoga texts (later, between the 8th and 11th centuries). Many of its elements and statements are considered subversive, such as the behavior of the Siddhas, but these writings have also been interpreted as rejecting literal meaning and assuming a symbolic narrative, as through a coded language: Sandhābhāṣā, a language "with intent," which is intentionally obscure to the uninitiated, being one of the main methods of Indian discourses, not unique to Buddhist traditions. Max Müller first translated this Sanskrit term as "hidden sayings," E. Burnouf in 1852 as "cryptic speech," and Haraprasad Shastri in 1916 as "twilight language", a term preferred by some recent scholars but also criticized by others). The translation "secret language" or "coded language" has also been proposed."
In Indian esoteric movements, a secret language has several functions, such as avoiding persecution and judgment on practices that were marginal according to social norms. In addition, secrecy gained symbolic meaning with its elitism and social empowerment, in which heterodox communities opposed the traditional class hierarchy. It also served as protection, in which knowledge considered dangerous was not divulged. On the other hand, the alleged danger and destructive power of the veiled teaching also generated attraction: announcing the existence of a secret to outside listeners was part of a frequent strategy of esotericism, that of pseudo-simulation, precluding its disclosure.
Numerology is also of importance to tantric terminology:
The fivefold classification presented in the tantras is remarkably comprehensive, embracing objects of every conceivable kind; it includes the infamous set of "five Ms" (fish, meat, wine, mudrā, sexual intercourse) and even a set of five "bodily fluids" (feces, urine, blood, semen, flesh). In addition, it includes sets of doctrinal principles, such as the five skandhas (factors of existence), the four kāyas (Buddha bodies), and the triad prajña, upāya, bodhicitta ("wisdom", "means", "enlightened mind"). Prajña, upāya, and bodhicitta are identified with the triads female/masculine/union, Amitābha/Akṣobhya/Vairocana, and so on, and thus are implicitly assigned to the groups of water, fire, and space, respectively.
Language and vocalization also acquired mystical connotations, as in the notion of Sanskrit having been considered a "sacred language," and its sounds and characters, from consonants and vowels to syllables and words, acquiring an occult and secretive background. In the Upanishads, one finds speculations about the mystical efficacy of ritual language and speech, as with the sound Om. The cryptic aspect of Vedic riddles was also professionally held by Brahmin priests, as initiates of the rituals of esoteric secrets. Public riddle rituals or riddle competitions were held at sacrifices, and verse riddles were also popular in private circles.
In several tantric sects, the phenomenon of sound production by the human body is considered to correspond to macrocosmic dimensions, as a replica of Creation processes, from the Origin, defining in Hindu theology a metaphysics of the Word and phonic and phonetic cosmogonies. Sound is seen as a divine substance, as well as with Sanskrit, justifying meditative techniques of mantra recitation in which there is correspondence to the symbolic meanings of each letter, syllable, or word and its sacrosanct chanting in mantras. In the Śakta Tantra, the sexual polarity of Brahman (male, and female) is considered to participate in cosmic evolution and creation in an analogy to human reproduction: the cosmic sound, nāda-brahman, is considered the primordial vibration resulting from the sexual act of Shiva and Shakti, which is transmitted to the vibrations of human activity and speech and is concentrated at the original point of sound, nāda-bindu. Thus, importance is assigned to oral instructions by a guru, such as of mantra formulas and bījas, which are symbolic. It is described in the opening verses of the Śāradā-tilaka Tantra (11th century):
From Shakti comes nāda, that is, the nasal sound represented by a semicircle and here put apparently for unmanifest sound. From nāda comes bindu, that is, the point representing anusvāra. This bindu possesses the qualities of the highest Śakti and is itself made of three parts, namely, bindu, nāda, and bīja. From the division of this higher bindu, the sound is produced. The sound that is thus created takes the form in letters and words. Letters and words form mantras; therefore, mantras embody, as it were, the power of Shakti, which is the power of Parameshvara .
According to these systems, the resonance emitted in the pronunciation of the letters and their combinations resonates in the creation of nāda-brahman in various effects, such as the unification of the practitioner in return to Brahman. The energy centers of the body (chakras) are also associated as reservoirs of latent letters and syllables (mātṛkās) according to their lotus petals, and the esoteric initiations called dīkṣās largely refer to this distribution of letters. Importance is also given to the Word (Vāc) in the Shaivist doctrines, such as the one by Abhinavagupta (c. 950–1016), with parāvāc as the uncreated and primordial Word (in essence, the highest level of reality, corresponding to pure consciousness, but also encompassing all levels of words). Thus, Tantrism recognizes greater psychosomatic and contemplative applications in a science of mantras (mantra-śāstra), connecting the vibrations (spanda) of sounds to deities, physical elements, and abstract concepts.
Meditative methods of visualizing deities were also inherited by Tantrism. In Buddhism, instructions for visualization precede the esoteric strands and are not unique to it, because they are also found in Shaivism.
One of the tantric groups best known for scandalous practices was the Kāpālikas, active in Medieval India, between the 7th and 8th centuries. Their name is derived from kapāla ("skull"), because they used a human skull as a begging bowl. They were followers of Shiva and revered the angry form of this god, Bhairava, imitating him in transgressive rituals, such as smearing their bodies with ashes from cremation grounds, orgiastic practices, human sacrifices, consumption of meat and alcohol. David Lorenzen considers, however, the scarcity of primary sources, and believes that historical information about them may be fictions of other traditions to disparage them. The only surviving sect today that is derived from the Kāpālikas is the Aghori, who are similar to their predecessors and usually dwell in mortuary camps. According to Ronald L. Barrett, they lean to both the "left-hand path" and the "right-hand path," and their mortuary Sādhanā serves to sever attachments and aversions, foregrounding primordiality in return for an uneducated and undomesticated view:
Aghor gurus and disciples believe that their state is primordial and universal. They believe that all human beings are born Aghori. Hari Baba has said on several occasions that human babies in all societies have no discrimination and that they play in their dirt as well as with the toys around them. Children become progressively discriminating as they grow up and learn the culturally specific attachments and aversions of their parents. Children become increasingly aware of their mortality as they hit their heads and fall to the ground. They come to fear their mortality and then mitigate that fear by finding ways to deny it altogether.
In Bengal, from the 17th to the 19th centuries there was a development of esoteric tantric groups with yogic practices, such as the Karthābaja and Vaiṣṇava Sahajiyā, involving sexual rituals, although to some extent there were exoteric expressions in devotional movements as well. As an example, in verses from the Amtarasāvalī (c. 1750) of the Vaiṣṇava Sahajiyā, an adapted analogy is employed: of the "river" as a "yogic channel" to which the sexual fluids and consciousness of the practitioner must travel from the mundane, to reach a celestial and beatific place called "The Place of the Hidden Moon" (guptacandrapur).
In the Mughal Empire of the 17th century, Prince Dara Shukoh made the first translation of the Upanishads into another language outside the Indian sphere, in the book of c. 1657 Sirr-i-Akbar ("The Great Secret"), with his personal interpretation. As in his other comparative work on Hindu traditions, Majma-ul-Bahrain ("The Meeting Point of the Two Oceans", c. 1655), Dara was influenced by the ancient Islamic historiography which considered that the Indians possessed a polytheistic religion of the masses, while a monotheistic aspect was reserved for an elite. Furthermore, in accordance with a perennialist tendency, he traced a monotheistic "esoteric truth" to the Indian work, and affirmed the god Brahman as being the prophet Adam, who would have made a revelation before Muhammad on par with the doctrine of tawhid ("Unity") in the Koran. He identified the Indian corpus as the "hidden book" (kitāb maknūn) and "mother of the book" (umm al-kitāb) mentioned in the Quran. Dara influenced the Western reception through Abraham Hyacinthe Anquetil-Duperron, who was the first European translator of the Upanishads and also considered them a source of hidden knowledge, believing in a "doctrina orientalis" according to categories of prisca theologia and Western esotericism.
From the 1880s onwards, scholars from South Asia, mostly Bengalis, intervened in the journal The Theosophist in favor of Tantra, comparing it to European occult doctrines and, in a manifestation of their own agency, publicized it with the term "Indian occultism".
Buddhism
"Esoteric Buddhism" is a modernly created designation, but corresponds in part to the East Asian phenomenon through the indigenous terms mijiao (密教) and bimi (秘密), which may be translations of the Indian term guhya ("secret"). The mere equation of these terms, however, presents problems. In general, the terms "tantric Buddhism," "esoteric Buddhism," and "Vajrayana"- vajra meaning "diamond" or "ray", regarding the unchanging and indestructible state of awakening - are also used interchangeably.
According to Ronald M. Davidson, the minimum requirements that define esoteric Buddhism are an entrance ritual, a mandala, homa rituals, mudras, mantras, and the caveat of secrecy. The earliest Dharma scriptures that describe ritual performances such as fire sacrifice (homa) and offering to the sacred fire (yajña) are from the sixth century, such as the Dhāraṇīsaṃgraha of Atigupta (Atikuta), which describes an arrangement of figures, ritual consecration, homa offerings, and conditions the establishment of mandala within a pavilion as secret, forbidding disciples to speak of it to anyone who had not been given abhisheka, whereas in the Amoghapāśahṛdaya, the abhisheka rite is presented not as a transmission ritual, but as a purificatory one to pacify the disturbances of a country. Ritual or mantra collections are traced to the 5th and 7th centuries, while collections of magic continue to the present. This early material is usually called "proto-tantric" in critical literature. Some of these compendia may have been alternatively referred to as Vidyādhara-piṭaka ("Sorcerer's Basket") and served as inspiration for other surviving collections, which have an affinity to Siddha literature as well.
Some point out that hidden Buddhist teachings may date back as far as the third century, according to evidence of tantric systems such as the Three Mysteries in the 密迹金剛力力士経 (Guhyakādhipatinirdeśa), and reports of transmission by orality, which left no material evidence. However, not all scholarly strands consider that esoteric Buddhism falls within the category of tantrism, or that all esoteric Buddhism would be tantric. The Pratyutpanna Samādhi Sūtra (1st century BCE-2nd century) can be considered proto-esoteric in its content and also a precursor of the Pure Land lineage. Although Tantra and Pure Land esotericism had different goals, the latter aimed to attain Sukhavati paradise and other Buddhist lands where even more sublime esoteric techniques could be developed. Both were developments of Mahayana and were not mutually exclusive.
Southern Esoteric Buddhism, also referred to as "Esoteric Theravada", presents esoteric transmission and meditative elements similar to those of Tantrism, but was not influenced by Tantric and Sanskrit literature; it appears to have developed independently and its texts are in Pali; differently from Vajrayana, there is an absence of sexual rituals in this esoteric Buddhist category.
One of the most distinctive features of esoteric Buddhism compared to esoteric Hinduism occurs in the symbolic assignment of the male/female polarity: in erotocentric Buddhist practice, the feminine is seen passively as "wisdom" (prajña), while the masculine is considered in the dynamic role of "method" (upaya); in esoteric Hinduism, the reverse is true: the feminine symbolizing power and activity, and the masculine wisdom and passivity.
There is a conflict within the non-esoteric and esoteric schools of Buddhism when it comes to the claims that the Buddha would have hidden nothing and revealed everything and that he would have reserved secret teachings. On the other hand, it is considered in pre-Mahayana (or non-Mahayana) scriptures that the Buddha did not reveal everything by keeping silent about unanswered questions, although they may have reconciled this with the claim that he had not withheld them either. There was a transition in the degree of secrecy and transparency between early and late Buddhism, at first emphasizing the transparency of the Buddha's teachings in comparison to the Vedic secrecy of the Brahmins. There are scriptures from the Pāli Canon that deny secrecy, as in the Mahāparinibbāṇa Sutta (Dīghanikāya 16 II,100), and also from the Mahayana, such as the Mahāparinirvāṇamahāsūtra tatagatagarba:
O Exalted One! How is [this]? Are there any secrets in what has been taught by the Exalted One? Please do not keep [any teachings] secret in the form of 'intentional statements' (ābhiprāyikaṃ vacanam: dgongs pa'i tshig = bsam pa can gyi tshig). O Exalted One! How is [this]? Are the Buddha's teachings similar to an illusory woman, a magical creation, created by the magical (diagrammatic) device (yantra: 'khrul 'khor) of an illusionist and magician?" [The Exalted One] replied, "There are no secrets in my teachings, and the Buddha's teachings, like a crescent moon in autumn, are spotless, untainted with marks, without confusion, free from secrets and great secrets, and are transparent (or clear).
Another considered dimension of the secret is that of epistemic mystery, seen by the Mahayana, in that ordinary cognition and conceptualization have no access to the extraordinary reality of awakened beings. Third and fourth-century Chinese texts already made the distinction from previous Hinayana doctrines, considered "exoteric" and simple, while they called the Mahayana esoteric (mijiao) and defended it as superior and profound. Vajrayana, on the other hand, considers what they call the "Secret Vehicle" (in Tibetan: gsang ba'i theg pa), a term consolidated in Tibetan texts attributed to Padmasambhava and others from the 11th century, equivalent to the Sanskrit expression guhyayāna found in tantras. Meanwhile, they attribute the "exoteric" or "external" (bāhya = phyi) to other non-mantric vehicles.
There is a degree of secrecy among the tantras, in classes and hierarchical systems, and Taranatha (1575-1634) suggests that secrets exist because they are of higher quality, impenetrable or hardly cognitively accessible, or rare. There are scriptures of the yogatantric system that state a commandment of "non-disclosure of secrets" of the mantric precepts, and dissemination of tantric scriptures or improper translations were forbidden by royal decrees. On this, Rongzompa (11th century) provides an explanation:[The kind of secret] that is unfit to know, consisting [as it is] of such [deeply] real and surprising types of [mantric] conduct, is not capable or suitable to be the domain of [ordinary] people of the world and [followers of] lower vehicles, and thus must be kept secret from [them], and thus [the vehicle that teaches such doctrines] is called the Secret Vehicle (gsang ba'i theg pa). (...) As for not disseminating secret teachings to unworthy [individuals], it is as the following teaches: [Only] if one performs activities for the benefit of sentient beings, through the lower vehicles, until a mind that knows such a [Vajrayana view] arises [in them] that sentient beings will be tamed, and not ruined. Thus [Vajrayana] must be kept extremely secret and is therefore taught as the Secret Vehicle.
Japan
Japanese esoteric Buddhism (Himitsu-bukkyō or Mikkyō) was created according to the Tendai and Shingon schools. To distinguish between them, Shingon was referred to as "Eastern Esotericism" (Tōmitsu), due to the location of one of its main temples in Kyoto, while the tendai esoteric practice (Mikkyō) was referred to as Taimitsu. In turn, Taimitsu was sudivided into the Ennin and Enchin lineages, while Tōmitsu was into the Ono and Hirosawa lineages. At the apex of Japanese Tantrism (11th to 14th centuries), the two competing Taimitsu traditions of Ennin and Enchin were referred to as Sanmon (Mountain branch) and Jimon (Temple branch), with a distinct set of rituals.
Some scholars of Japanese Buddhist history have also distinguished a "pure esotericism" (junmitsu) of the Heian period, formed by the Tendai and Shingon traditions transmitted from China and whose practices emphasized the transformation of the practitioner into an enlightened being, in contrast to a "mixed esotericism" (zōmitsu) of the Nara period, which was more devoted to ritual recitations of daranis and rarely to mudras and visualizations, as well as aiming more at healing and the hither of supernatural powers rather than enlightenment. However, this paradigm is questioned, as this pair was conceived only in the mid Tokugawa period, and uses of doxographies and taxonomies such as these may be anachronistic.
Historians have traditionally considered the Tōmitsu branch as the "orthodox" one of Japanese tantrism, due to the relevance of Kūkai, but the Taimitsu tradition also developed some contributions to East Asian tantrism, such as their scholastic study of the concept of "esoteric" and its reformulation, seeking to categorize the esoteric teachings (emmitsu itchi) in a taxonomy. Moreover, they accomplished the creation of a third hermeneutic category between the Womb and Diamond Mandalas: the Lotus Mandala, which encompassed the previous two and was emblematic of non-duality and the overcoming of esoteric and exoteric. There were different levels of meaning in the scholastic classifications of the clerics, in which many of the esoteric teachings used non-esoteric teachings of the Mahayana traditions, and the esoteric and exoteric had some degree of identification.
Thus, according to Lucia Dolce, a simple dichotomy between the esoteric and secret that is not esoteric is not possible, and the Taimitsu likely tried to build an alternative system of Mikkyō, based on the ideal of unity of esoteric and exoteric. There was a process of esotericization in medieval Japan, with constant alternations between esoteric and exoteric in ritual programs. As stated in the Keiran Shūyōshū (14th century), the secret meaning of the esoteric is found in multiple combinations of esoteric and non-esoteric elements, and the exoteric and esoteric are the same (kenmitsu funi). In the exegesis of the esoteric liturgies of the Lotus Sutra, they are presented by the encyclopedist as the "secret within the exoteric-esoteric system" (kenmitsu chū himitsu).
In Japan, Ennin was the first to propose the idea of a doctrine above the conventions of distinguishing esoteric from exoteric, called the "great perfect teaching" (ichidai engyō). Another great systematizer of esotericism besides Kūkai, the monk Godai'in Annen formalized Tendai esotericism and considered the esoteric to encompass all reality, all places, and all times, as he considered all the Buddhas of the world and their teachings to fall under the category of "esoteric Buddhism" (unlike what his predecessors claimed). Dohan (12th-13th century) analyzed the diversity of approaches to the Pure Land esotericism of his time.
Taoism
Taoism has a rich history of continuously developing esoteric practices over the centuries, along with the integration of various techniques from other traditions, such as communication with spirits, meditation, body movements, medicine, and "internal alchemy". There are thousands of Taoist texts of an esoteric nature, as in the Daozang compilation (ca. 400) or in the canonical collection of sacred texts of 1444. Its association with esotericism was popularized in the West during the 20th century.
Much of the Taoist religion was derived from native Chinese cosmologies and mantic systems, mainly during the Han dynasty (206 BCE-220), in correlative schemes of Yin and Yang and the "Five Phases" (Wuxing) of the natural world, in macrocosm and microcosm of Heaven (Tian), Earth and Humanity; but also with augury prediction present since the Shang dynasty (such as the I Ching). For a long time these practices were passed on in private groups and were considered revelations, and mantic texts from this time can be considered precursors of Taoist theserae or talismans (fu). Several esotericizing devices can be identified, such as presenting in the text nomenclature as fang (方, "recipes" or "methods"), mi (密, "secret") or jin (禁, "forbidden").
Chinese manuscripts of occult knowledge also circulated - which already constituted since the 3rd and 4th centuries B.C. a separate field of knowledge and popularized a "culture of secrecy" in which, although the texts occasionally prescribed a convention of secrecy, did not necessarily occur; claiming it to be secret promoted the valuation of the knowledge and the manuscript. This culture was widely spread beyond religious specialists. A popular example was the "daybooks", with hemerological content to indicate which days were favorable and unfavorable; hemerology was a constituent part of several types of occult technical literature, as among some Mawangdui manuscripts.
In addition to the official system of the Five Classics, there was also the unofficial private transmission of other texts at this time, such as those on spiritual transcendence, alchemy, stargazing, immortality, and the Tao. Many experts in these techniques and the Tao were sponsored by the royalties, and were called "masters of recipes" or "magicians", "masters of technique" or "masters of the Tao (fangshi)." They were closely associated with mantic practices, and in the early 2nd century B.C., the Huang-Lao tradition flourished, which associated Laozi with cosmological knowledge and divination around the Yellow Emperor. Unlike Confucian methods, publicly transmitted by the state, these Taoist methods were taught in a secretive manner and sometimes associated with political contestation. Often the fangshi spread esoteric counterparts to the classical texts, which were collectively called "apocryphal" (chenwei), with prophetic messages accessible only to initiates.
Taoist scriptural transmission, in part stemming from the fangshi, was more elaborate than earlier secular counterparts, and one of the earliest descriptions of a grant of magical texts appears in the works of Ge Hong, who received esoteric alchemical works from his master around the year 300.
Their ordination rituals were also highly formalized and esoteric. There was no single investiture to the Taoist priesthood, as there was more than one body of scriptures. By the end of the period of the Northern and Southern dynasties, seven clerical orders were based on seven canons, produced between the years 150 and 500. These orders did not compete with each other and each could grant new titles to the ordained in investiture rituals, which ranged from 3 to 9 days. Each order distinguished itself as a lower or higher degree according to the period. The first effort to define an ecclesiastical and canonical hierarchy was found in the Lingbao scriptures (ca. year 400).
The Shangqing Canon ("Higher Canon of the Purity of the Great Cave") is documented as one of the Taoist revelations that appears to have been the product of ecstasy: between 364 and 370, a group of Perfect Ones reportedly descended to convey scriptures and instructions to Yang Xi in night visions. He and his associates transcribed them, and their records were passed down to a small number of heirs, until they were compiled into a critical edition, Zhengao, around the year 500. By the beginning of the Tang period, it was accepted as the supreme rank in the clergy, considered a superior body to the others and of greater prestige. Because of this, an order was formed to perpetuate this canon, and was the subject of esoteric transmission to an elite, who were initiated into its mysteries in order to achieve individual spiritual perfection.
Women in Taoism were given great importance by the Shangqing school; they had a role as divine teachers, revealers of secrets, and bestowers of esoteric teachings of the Tao, which was actively continued until the Tang dynasty. In contrast to the school of the Way of the Heavenly Masters (Tianshi), the Shangqing regarded rituals of sexual intercourse as of lesser importance, considering that "mixing the qi" and physically harmonizing the Yin and Mahayana did not lead to eternal life. Thus, it viewed women not so much as consorts or sexual partners. During the late imperial period (until the Ming dynasty), they were associated with supernatural connections, healing powers, and shamanic techniques, and powerful female foundresses and priestesses emerged. The female body was also considered essential to the processes of spiritual transformation in later doctrines of internal alchemy.
The Lingbao canon was considered to be the second highest in importance in the ranking. It was seen as sacred because it was supposedly formed spontaneously from primeval forces of the universe and revealed by a very high deity. A recorded example of initiation into this canon was of the two princess daughters of Emperor Ruizong of Tang in 711. Procedures guided by a preceptor are described, who performs transmissions in several stages, among which there is the giving of talismans, the performance of esoteric chanting, and the reading aloud of secret scriptures, some of them about esoteric interpretations of the Tao Te Ching. The liturgies involved a division of space in the four cardinal directions; a center; and a direction to the Perfect Ones, which were associated with energies, stations, items, colors, gates, postures, and choreography. The officiant also invoked spirits, immortals, and the Perfected to participate in the ceremony.
In the Tang period (618-907), Taoist medical practices and prescriptions were well received even in Japan, through Buddhist sutras, as well as methods of divination, such as the astral cult. From the Tang dynasty on, and especially from the Song period on, a new branch of esoteric doctrines and practices called Neidan ("internal alchemy") was developed, whose main characteristic was internal meditation expressed in alchemical language, in addition to the symbolism of the I Ching. They employed a synthesis of various traditions, plus ancient correlative cosmology and terms from the tradition of external alchemy (Waidan), but considered the arrangements of these cosmic emblems to be "images" (xiang) that mediated absolute reality to the mundane. The primordial state to which internal alchemy attempts to return, Non-Existence or Pure Yang, can be represented by the "Golden Elixir".
There are medieval diagrams called "true form charts" (zhengxin tu, 真形圖) that were transmitted privately and used in rituals. They contained aniconic emblems mixed with text, considered the esoteric manifestation of sacred scriptures or the cosmic qi itself condensed at the moment of the creation of the world and reflecting celestial writings. Thus, they were considered the highest sacred scriptures. Its images were supposed to evoke in the practitioner imaginative experiences about interrelationships between body, cosmos or geographical elements, and it was believed that contemplating them could lead to immortality and the inherent truth of the formless Dao. "True form" could also have been a response to competing medieval Buddhist doctrines.
After the An Lushan rebellion, there was more religious openness, but at the same time unaffiliated practitioners of Taoism, supported by local warlords, decided to reshape the Taoist systems. A proliferation of schools of Taoism emerged, with new rites, gods, and initiations into new hierarchical and revelatory traditions. Some began to question the orthodox canons in the Tang dynasty. This intensified later in the Song period. There were innovations such as the one by Du Guangting (850-933), who established a model for rituals to the dead (zhai) and was flexible to the cults of local gods, trying to counter the threats of esoteric Buddhism and popular religions to Taoism. Meanwhile, other conservative Taoist priests attempted to return to the ancient practices of classical rites. Du reports the emergence of rites that would be consolidated later, such as a cult of Xu Xun (292-374), called "Pure Brightness" or "Path of Loyalty and Filiality" (Jingming zhongxiao dao), and therapeutic rites of the Zhang family of Heavenly Masters.
There are also reports from the time of extracanonical rites of exorcism, invocation of souls, and "Rites of Thunder" performed by folk magicians outside the established traditions. There was a large influx of Tantric Buddhism, with Taoists incorporating mudras, mandalas, and internal meditation for merit accumulation and ritual efficacy. In the last two decades of the Northern Song dynasty, there were Heavenly Masters who made elaborate schemes to articulate the powers of thunder, and the Thunder Rites also spread to the Southern Song dynasty, along with practices from the schools of the Golden Elixir, the Divine Empyrean, and the Heart of Heaven. The Emperor and the state would continue to sponsor Taoists seeking spiritual protection.
During the Southern Song dynasty, it was also considered that local gods were under the control of the Tao in the scriptures transmitted in "spirit writing" rituals, for example, following the ancient cult of Xu Xun: his spirit was evoked in 1129 by the cultic leader He Zhengong, and in 1131 he allegedly received secret rites from the spiritual patriarch. The cult of Xu Xun had a revival later in the 13th century. Another Taoicized deity was Wen-ch'ang, God of Literature in rituals, and his supposed revelations in spirit writing indicated multiple reincarnations of him and the instability of the Song dynasty. Taoist cults and practices such as mind rectification continued to be sponsored in the Yuan and Ming dynasties, with state support.
During the Qing period, the practice called "spirit writing" (fuji) was widespread among lay people. It was an oracular technique for channeling communication between the realm of deities, and the devotees who used it were not particularly Taoist, but it still exerted influence on this religion and also changed with its development. The practice became widespread in the 11th century, both among high officials and scholars and among lay people. Scriptures said to be "written by spirits" are found in the Ming Daozang. In the early 17th century, spirit-writing altars (also called "phoenix halls") multiplied in private domestic settings, by small groups headed by literati, devoted to the worship of the immortal Lü Dongbin. These groups were not founded by monks and made a shift from institutionalized religion to personal, local religiosity. There was a network of lay people in various regions who held such a spirit-writing cult and continuously received alleged spiritual texts on self-cultivation and internal alchemy refinement. Pan Yi'an (彭伊安), a 17th-century recipient of the text that in the West came to be translated as The Secret of the Golden Flower, describes his process of initially composing the first part:
From what I remember, it was in the Wu Shen year [1668] that our holy patriarch Chunyang [i.e., Lü] began transmitting the 'Instructions'. No one other than these seven received this transmission. The most profound teaching was [expressed in] no more than one or two words. It could not be put into words and letters. Then the seven questioned the Patriarch in detail. Since our holy Patriarch spared no mercy in clarifying, [their teachings were] compiled for days and months. Eventually, they composed a volume.
The practice became popular in various syncretisms and new sectarian groups in the 19th century. With the establishment of the People's Republic of China in 1949, these communities were seen as "reactionary secret societies," and it was largely abolished.
Taoist methods were influential in the culture of esotericism in Japan, being adapted by Yin-Yang diviners and esoteric Buddhist monks. Talismans and magic were also used in Shinto and Shugendō. Taoist-style astral worship also came into vogue there from the 7th century onward, when emperors were associated with constellations. There was a spread of practical connotations of immortality and books on longevity techniques. Through the esoteric Tendai and Shingon Buddhist doctrines, Chinese practices, and objects such as talismans and magic, rituals for the protection of residences, and other Taoist-inspired beliefs were brought over. In the Heian period, the Chinese administration system was imported, including the creation of a special Yin and Yang Bureau (Inyôryô), which used Yin-Yang cosmology and astrology by officials, to divine fortune. These methods of divination spread to the aristocracy in the 10th century, for personal fortunes and spells of protection against bad luck and dangers, resulting in the practice called inyôdô.
Confucianism
From the 4th to 3rd centuries BCE, master-disciple lineages that interpreted Confucian texts like the Spring and Autumn Annals beyond the content of historical chronicle, including expanded meanings that would constitute strands of "esoteric classicism" emerged. By the 2nd century B.C., there were interpretative schools that were consolidated by a mainly oral tradition, such as the Gongyang School that claimed to hold the direct secret knowledge transmitted by Confucius to Zixia, which ended up reaching the founder Gongyang Gao. Interpreters of Gongyang considered that Confucius was driven to disguise his message in "esoteric language embodying ultimate principles" ("esoteric sayings and great dogmas, "weiyan dayi") for reasons of an unrealized kingship in his lifetime or because of a lack of power or effectiveness in establishing the Way from his state office. The Gongyang Zhuan ("Gongyang Commentary") is his earliest surviving explanation, originally having been transmitted orally for about three centuries before the Han dynasty until it was consolidated into writing in the second century BCE. In it, sentence by sentence and word by word, the commentary decodes linguistic clues from Confucius' sayings. Thus, the Gongyang School established itself as the source of the most strongly esoteric and eschatological method of reading the Annals.
During the Han dynasty, Confucianism was consolidated as the main religion, but with several strands. Dong Zhongshu (195-105 BCE), a dominant intellectual during the reign of Wu of Han, modeled Han Confucianism after Gongyang's interpretations, promoting a systematization and influencing the production of his canon. He relied on concepts of Yin-Yang cosmology, preordinations, and interpretations of auspices that determined the historical changes and destinies of dynasties. This strand established itself as a state orthodoxy, especially after a canon by Wu and the prophetic use made by Wang Mang. In 136 BCE, Emperor Wu decreed "the abolition of the Hundred Schools of Thought and the supremacy of Confucianism alone." In the 2nd-Ist centuries BCE, Chenwei (讖緯) scriptures appeared: the wei were claimed to complement the classics and to contain their esoteric meaning, while the Chen were oracles and predictions derived from esoteric interpretations. They had political use for prognosticating the rise and fall of dynasties and were employed by the ruling classes. However, the failures of Emperor Wang Mang's tenure led to the discrediting of the Gongyang and the Chenwei. Confucian scholars replaced the then-dominant form of Confucianism with another that became known as the "Old Text School," which was skeptical of the supernatural character of the previous school. By the late Han period (3rd century), the elimination of the esoteric aspects of Confucianism occurred. The Chenwei ceased to be authoritative interpretations of hidden meanings of the classics and was banned in 282 by Emperor Wu of Jin. In 485, Xiaowen ordered the burning of the Chen books. There were other proscriptions over the centuries in later dynasties.
The characteristic of this early Han Confucianism, which became heterodox, was the esoteric combined with a political nature, as a utopian Confucian messianism: the idea of a Golden Age to be realized by an emperor-wise who establishes the cosmic order by self-cultivation of celestial principles. Confucius was also deified as an omniscient prophet who knew what was set to happen, and emperors exploited the superstitions and his alleged prophecies for their own interests. In some apocryphal texts, he appeared as a giant figure with nine heads. One example is the passage in his biography in which the qilin is captured on a hunt: in the Han apocryphal A Confucian Letter Explaining the Secrets of the Annals, this creature serves as an advertisement for political changes and the continuation of Confucian secret teaching even after Confucius' death.
After Lin was captured, the sky rained down the blood that transformed into writing at the main gate of Lu's capital, and that read, 'Prepare the laws quickly, for the sage Confucius will die; Zhou will be destroyed; a comet will appear from the east. The Qin government will arise and suddenly destroy the literary arts. But although the written records will then be dispersed, the teachings of Confucius will not be interrupted.
At the end of the 18th century, esoteric interpretations resurfaced as the "New Text School". Philological in nature, they sought to rescue the classical texts that were no longer orthodox after Wang Mang. It was started by Zhuang Cunyu (1719-1788), a classicist scholar who, in his research, rediscovered the Han exegetical tradition of the Gongyang, which was ignored by philologists of his time. His works remained in obscurity until they were recognized by Liu Fenglu (1776-1829), Song Xiangfeng (1776-1860), Gong Zizhen (1792-1841) and Wei Yuan (1794-1857). These interpretive trends led to practical use in political reformism, culminating in Kang Youwei (1858-1927), who made it a radical interpretation and denounced the bankruptcy of the Qing dynasty government. From the Gongyang writings, which he considered to be the true teachings of Confucius, he applied the notion that humanity moved in a linear direction to a progression of Three Eras: from the Age of Chaos to the Age of Ascending Equality, and then the final Age of Great Unity.
Islamic esotericism
Liana Saif questions the delimitation of "East" and "West" in the matter of esotericism as generating ambiguities, especially concerning the Islamic nations, which considered themselves "West" in the eighth and ninth centuries, in relation to the East of India and China, although Europeans considered them as eastern. In turn, there was a cultural crossover from Buddhism, Hinduism, and Zoroastrianism ("Eastern" on the part of Muslims) that influenced Islamic religious and esoteric practices. Moreover, Islamic cultures from Al-Andalus were called "the West" (Maghreb), while cultures from the Levant to Persia were considered "the East" (Mashriq).
Esoteric Islam developed along with Western philosophy as well as native Arabic practices. There was a cross-fertilization of notions of "esotericism," with the Arabic terms batin and al-ghaib Islam referring to veiled or secret teachings. According to Mark Sedgwick, al-ghaib is the only one of the two terms that appear in the Koran, referring to "meanings and ideas" or discursive concepts, in contrast to batin, which refers to "realities" or objects of content. However, Neoplatonism was largely responsible for developing this concept of esoteric ideas: "Ancient philosophy, and especially Neoplatonism, was also important in developing a large historical body of the Islamic batin discourse including al-ghaib which can, on this basis, be called 'Islamic esotericism'." In turn, this strand of Islamic study was transmitted to the Latin world in the 12th and 13th centuries, and also later in the 19th century. Helmut Zander, however, does not agree that it is possible to refer to either Neoplatonism or batin with the current Western category of "esotericism," and suggests that the dimension of the "secret" is a possibility, but not necessarily present in those other systems that can be called esotericisms.
Due to Orientalism, the concept of "l'ésoterisme islamique" ("islamic esotericism") was coined within the traditionalist school, with a perennialist focus, reducing esoteric Islam almost exclusively to Sufism. This view was greatly influential in the academic studies of Henry Corbin. Because of this, Islamic philosophies such as those of Avicenna and Suhrawardi were incorporated within "Western esotericism" and analyzed according to these limiting categories.
Early Western reception
The earliest Western source to distinguish between exoteric and esoteric Buddhist doctrines was the Sumario de los errores (1556), produced by Jesuits in Japan. From a misinterpretation of the divisions of Buddhist schools and concepts of Zen Buddhism, the work claimed that the Japanese Buddhist clergy preached a "false" doctrine to the lay population (about punishment in Hell and reward in the Pure Land), but that the priests did not believe it, reporting that "the inner core of their law" stated that "there is no soul or life in the hereafter, and that everything ends with this life." It also stated that Buddha's life had passed through stages, and that in a materialistic phase he would have written 9 books, in an exoteric phase 4 books, and finally, in the esoteric phase he produced a single book, in which he considered the previous teachings as merely convenient. This description contributed to the spread in Europe of the "internal doctrine" of Buddhism and subsequently influenced the Western perspective on the philosophy and religion of the East in the 16th and 17th centuries.
Melchior Nunes Barreto was convinced that this dichotomy of a true hidden doctrine and a false external one permeated even the Japanese vocabulary, whereby words could admit both an open public sense and an esoteric sense reserved for the initiates; he realized that the missionaries' ignorance of the hidden sense led to mistakes. In a Catechism of 1586, priest Valignano gave another description of the "internal doctrine" of Buddhism, considering crucial its distinction from the "external doctrine", referring to cultic traditions to deities, such as prayers and ceremonies, and beliefs of Heaven and Hell. In contrast, the "internal doctrine" affirmed a single eternal but non-intelligent principle, alien to the world, and yet identical to everything and to the minds of men, to which it would be possible to join in this life through meditation. Such descriptions were considered principles of "Eastern philosophy" by European interpreters.
João Rodrigues, in the early decades of the 17th century, described the Chinese doctrines of Confucianism, Taoism, and Buddhism from these perspectives and considered that the "external doctrines" would have been conceived by literati and sages "for the people and adapted to their needs (...) for the political administration and peaceful welfare of the people," as opposed to what he called speculative doctrines:
The three sects of the Chinese follow entirely this way of philosophizing. They have two kinds of doctrine. The one they consider true is secret, and only the literates understand it and teach it by employing symbols. The other, vulgar... is considered by the literati to be false in the ordinary sense. They make use of it for divine as well as for civil and fabulous worship, and thus lead the people to good and keep them from evil.
The other method is speculative and deals philosophically with what God is, how this world was made, and everything else related to it. All this doctrine is hidden in various very obscure symbols that only a few people understand. and profess to be the greatest secret.
Until I entered China, our Fathers of China knew practically nothing about this [distinction between external and internal teachings] and about the speculative [internal] doctrine. They knew only about the civil and popular [external] doctrine because there was no one to explain and enlighten them."
Niccolò Longobardo followed Rodrigues' description that an atheistic original philosophy traced to Zoroaster would underlie Greek and Oriental philosophies as a whole, and, in a work from around 1624, regarded the cryptic texts in the East as symptom of "the birth in all nations of two kinds of sciences, one true and secret, and the other false and public."
In general, it was with the emergence of orientalist academic studies in the 17th and 18th centuries that there was a great sedimentation of the category of esotericism in a comparative manner in relation to Persian, Arabic, Indian and Chinese texts and practices. Abraham Rogerius wrote an influential work in 1651 in which he referred to "occult paganism" among Indians. Johann Jakob Brucker would reference the "esoteric doctrine of Buddha or Foë". This discourse about the presence of esotericism in the East had then become current, found in several works and authors, such as Johann Friedrich Cotta, Michael Hißmann, Friedrich Schlegel, the Encyclopédie (1756) and others.
Leibniz advocated for Agostino Steuco's concept of "perennial philosophy", that there would be a universal source present in all religious traditions, and took an interest in Chinese systems in his correspondence with the Jesuit Joachim Bouvet, who was sent on the first French mission to China. Bouvet, in his letters, also considered Chinese religion from a Western esoteric perspective as if it were a "prisca theologia" and "hermeticism," with the belief that the Chinese would possess eternal wisdom of Creation from before the Flood. In 1700, he described the I Ching as containing: "many precious remains of the debris of the most ancient and excellent philosophy taught by the first Patriarchs of the world to their descendants, since corrupted and almost entirely obscured by the course of time." John Toland in 1720 would affirm what is today called "esoteric distinction" as being a universal phenomenon, present not only in the West but also in several Eastern peoples.
Emanuel Swedenborg refers to an "Old Church" originating from lost teachings about the "pure correspondences", whose language reflects, according to his system, hidden spiritual realities. He points out that the remnant of this "Old Church" would be in China, or among the "Tartars" in the "Great Tartary". This, in addition to vague references to Chinese and Indians in Yogic postures, raised conjectures by late 19th century theosophists, as well as by late 20th and early 21st centuries scholars that Swedenborg was referring to Tibet or Siberia, or that he knew about esoteric Buddhism from contacts and trade routes, as well as the similarity of his esoteric practices with Asian counterparts. The reception of Swedenborg's mystical works translated into Japan and the literary speculations of Western esotericism of the late 19th and early 20th centuries also influenced exponents of modern Asian Buddhism.
Notions that a "pre-Kabbalah" was found in a Chinese or Asian Revelation before the Jewish one was proposed by James Parsons and assimilated in Scottish Masonic circles, with a major diffuser of this being Andrew Michael Ramsay in his book The Philosophical Principles of Natural and Revealed Religion (1748-49).
A posthumous essay by Michel-Ange-André Le Roux Deshauterayes described in its first part the "esoteric doctrine" of Buddhism; it was read by Schopenhauer in 1826, who was greatly influenced by the work.
Abel Rémusat and Brian Houghton Hodgson identified what they called the "esoteric Buddhism" of Nepal, Tibet and China as a distinct and non-atheistic doctrine, as it affirmed an intelligent first principle called the Adi-Buddha; they noted that there was an internal categorization of texts called Tantra/Upadesha as an esoteric one. Horace H. Wilson in 1832 also focused on this esoteric Buddhist doctrine. In 1827, Henry Colebrooke discussed the "esoteric brāhmana".
In the book Isis Unveiled (1877), Helena Blavatsky attempted, according to Devin Zuber, to "incorporate every conceivable aspect" of "Eastern and Western esotericisms." She also wrote that Swedenborg had a Revelation of Buddhist and Hindu esoteric teachings from Tibet. Another important book in the theosophical society context was Esoteric Buddhism (1883) by Alfred Percy Sinnett. Max Müller repudiated the Theosophists' claims of the existence of an "esoteric Buddhism" or esoteric Indian doctrines.
References
Eastern
Religion in Asia
Religion in the Middle East
Hinduism
Buddhism
Tantra
Shinto
Taoism
Confucianism | Eastern esotericism | [
"Biology"
] | 18,167 | [
"Behavior",
"Human behavior",
"Spirituality"
] |
74,053,348 | https://en.wikipedia.org/wiki/MANTIS%20%28space%20telescope%29 | MANTIS (Monitoring Activity from Nearby Stars with UV Imaging and Spectroscopy) is a planned NASA space telescope. MANTIS will study the emission of ultraviolet (UV) radiation of stars, especially in the extreme UV range, to judge the habitability of planets orbiting them. The telescope will be built by the University of Colorado Boulder as a cubesat at a cost of $8.5 million.
Ultraviolet radiation and stellar flares can impact the habitability of planets. For many stars, MANTIS will perform the first measurements of extreme UV emissions.
References
Space telescopes | MANTIS (space telescope) | [
"Astronomy"
] | 113 | [
"Space telescopes"
] |
74,054,198 | https://en.wikipedia.org/wiki/NGC%205506 | NGC 5506 is a spiral galaxy located in the constellation Virgo. It is located at a distance of about 75 million light years from Earth, which, given its apparent dimensions, means that NGC 5506 is about 80,000 light years across. It was discovered by William Herschel on April 15, 1787. It is a Seyfert galaxy.
Characteristics
NGC 5506 is a spiral galaxy seen edge-on, with dust lanes visible south of the nucleus.
Active nucleus
The nucleus of NGC 5506 has been found to be active and it has been categorised as a narrow line type I Seyfert galaxy, and is the brightest such nucleus. The classification of the active nucleus had been an issue of debate, as it lacked broad emission lines in the visual wavelength. However, broader lines were observed in the infrared, indicating that the broad line region is obscured in visual light.
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 mass of the black hole in the centre of NGC 5506 is estimated to be based on stellar velocity dispersion and based on the MBH–σ⋆ relation and X-ray variability.
NGC 5506 is a bright X-ray source, detected by all X-ray space observatories, starting with Uhuru. The X-ray spectrum indicates that there is both a compton-thick and a compton-thin absorber. The compton-thick absorber is a dust torus around the supermassive black hole at a distance of around one parsec, while the compton thin absorbs the softer X-rays emitted by the nucleus. The soft emission by the nucleus extends to a distance of about 350 pc and is attributed to reflection of the nuclear emission by photoionized gas. The inclination of the accretion disk is estimated to be between 40° and 50°. The iron line is complex, indicating emission by neutral and ionised iron. A broad component of the Fe Kα fluorescent emission line was observed by XMM-Newton.
The galaxy also emits radiowaves. The galaxy exhibits a central source that accounts for 75% of the total emission and diffuse wing-like emission towards the north-west and east of the nucleus and a low-surface-brightness halo measuring 2.75 arcseconds in diameter that surrounds these features. The features have no clear axis of symmetry. The galaxy has been found to host an megamaser.
Nearby galaxies
NGC 5506 is the foremost galaxy in a galaxy group known as the NGC 5506 Group. Other members of the group include NGC 5507, while IC 978 lies a bit farther away. Garcia identified as members of group also the galaxies NGC 5496, and UGC 9057. NGC 5506 forms a pair with NGC 5507, which lies 4 arcminutes from it. The group is part of the Virgo III Groups, a very obvious chain of galaxy groups on the left side of the Virgo cluster, stretching across 40 million light years of space.
References
External links
NGC 5506 on SIMBAD
Spiral galaxies
Peculiar galaxies
Seyfert galaxies
Virgo (constellation)
5506
387
Markarian galaxies
50782
Discoveries by William Herschel
Astronomical objects discovered in 1787 | NGC 5506 | [
"Astronomy"
] | 673 | [
"Virgo (constellation)",
"Constellations"
] |
66,819,673 | https://en.wikipedia.org/wiki/Translatomics | Translatomics is the study of all open reading frames (ORFs) that are being actively translated in a cell or organism. This collection of ORFs is called the translatome. Characterizing a cell's translatome can give insight into the array of biological pathways that are active in the cell. According to the central dogma of molecular biology, the DNA in a cell is transcribed to produce RNA, which is then translated to produce a protein. Thousands of proteins are encoded in an organism's genome, and the proteins present in a cell cooperatively carry out many functions to support the life of the cell. Under various conditions, such as during stress or specific timepoints in development, the cell may require different biological pathways to be active, and therefore require a different collection of proteins. Depending on intrinsic and environmental conditions, the collection of proteins being made at one time varies. Translatomic techniques can be used to take a "snapshot" of this collection of actively translating ORFs, which can give information about which biological pathways the cell is activating under the present conditions.
Usually, the ribosome profiling technique is used to acquire the translatome information. Recent advancements, including single-cell ribosome profiling, have significantly improved the resolution of these studies, allowing researchers to gain insights into translation at the level of individual cells. This is particularly important for heterogeneous cell populations, where overall bulk measurements may mask important cell-to-cell differences in protein synthesis. Other methods are polysome profiling, full-length translating mRNA profiling (RNC-seq), and translating ribosome affinity purification (TRAP-seq). Unlike the transcriptome, the translatome is a more accurate approximation for estimating the expression level of some genes, since the correlation between the proteome and translatome is higher than the correlation between the transcriptome and proteome.
History
Nearing the completion of the Human Genome Project the field of genetics was shifting its focus toward determining the functions of genes. This involved cataloguing other collections of biological materials, like RNA and proteins in cells. These collections of materials were called -omes, evoking the widespread excitement surrounding the sequencing of the human genome. The term translatome was first proposed in 2001 by Greenbaum et al. The translatome was intended to describe the relative quantities of proteins in a proteome. The term translatome now generally refers to the collection of proteins actively being created in a cell. Translatomics, in combination with degradomics, aims to describe the net change to the proteome under different conditions.
Relevance and contribution to omics
The aim of genomics is to study the genome, or the collection of genetic material in an organism. Genomics subfields, or other -omics, such as Transcriptomics and proteomics aim to characterize genome function by quantifying products of the genome (such as RNA and proteins) under different conditions. In doing so, omics gain insight into different levels of regulation of gene expression and therefore genome function. However, these fields characterize biomolecules that have already been formed. In some cases, RNA or protein abundance does not reflect function because these biomolecules may be degraded rapidly, or they may remain in a cell long after they are initially synthesized. When using proteomics techniques to study the proteome, regulation of protein abundance at the level of post-translational modification and protein degradation may obscure earlier regulatory processes. Because cellular functions are often regulated at the level of translation, meaning the transcriptome does not always reflect genome function, using translatomics techniques to study the translatome may allow one to observe regulation of genome function that would be obscured in transcriptomics or proteomics studies.
Methods
Translating mRNA Messenger RNA
Most translatomics techniques focus on characterizing the mRNAs that are complexed with ribosomes and therefore being translated.
Polysome profiling
Polysome profiling is a technique used to characterize the degree of translation of one or more mRNAs. A highly translated mRNA exists as a polysome, meaning it is complexed with multiple ribosomes. mRNAs translated at lower levels are complexed with fewer ribosomes. In polysome profiling, a sucrose gradient is used to separate molecular complexes in a cell lysate based on size. The fractions from the column are analyzed by sequencing or other methods. The translation rate of mRNAs is determined based on its detection and abundance in the fractions of lower and higher molecular weight.
RNC-seq
The full length translating mRNA (RNC-seq) involves centrifugation of lysated sample on a sucrose cushion. This allows separation of the Ribosome-nascent chain complex(RNC) from free mRNAs and other cell components. The RNCs form a pellet in the centrifugation that is collected for further analysis. The mRNA being translated in these RNCs can be sequenced, allowing identification and quantification of the mRNAs being translated at the time. However, RNC-mRNA complexes are fragile which can lead to ribosomes to dissociate from the mRNAs and degradation of mRNAs, potentially biasing the collected results.
Ribo-seq/Ribosome profiling/Ribosome footprinting
In Ribosome profiling, cellular mRNA including polysomes is subjected to ribonucleases, enzymes that cleave RNA. Those positions in the RNA molecules that are bound by ribosomes are protected against digestion. After cessation of ribonuclease activity, these protected sites can be recovered and sequenced. The sequences obtained from ribo-seq therefore represent fragments of mRNAs that were being actively translated.
TRAP-seq
TRAP-seq is used to identify mRNAs being actively translated in a specific cell type within a tissue or other assortment of cells. The cell type of interest is engineered to express a ribosomal subunit fused to an epitope tag such as green fluorescent protein. After cell lysis, antibodies targeting the epitope are used to isolate mRNAs that are bound to the ribosomes containing the fusion proteins. This RNA is then converted to cDNA and sequenced. This technique specifically identifies mRNAs that were being translated in the cell type of interest.
Nascent Polypeptides
Folding States
Mass Spectrometry
Mass spectrometry methods are unable to determine folding of nascent polypeptides. No current methods examine the folding states of nascent polypeptides globally in the cell. There are methods for examining the folding state of individual nascent polypeptides.
One method uses a nonspecific protease to cleave the nascent peptide at a low temperature. The protease can cleave the unfolded, flexible regions, but cannot cut tightly folded regions. The products of the cleavage can then be separated and studied to determine the folded regions of the nascent peptide.
Nuclear Magnetic Resonance
To analyze the full structure of a nascent polypeptide, nuclear magnetic resonance (NMR) is used. NMR allows a dynamic view of molecules in solution and so can be used on ribosome-nascent chain complexes (RNC). Labelling of ribosomes allows the NMR data to be filtered for suspected ribosome signal and identify the signal of the nascent polypeptide.
Identification and Quantification
While the structure of nascent polypeptides is currently unexaminable on a global scale, identification and quantification is not.
Stable Isotope Labeling by Amino Acids in Cell Culture
One method uses a variant of Stable isotope labeling by amino acids in cell culture (SILAC). SILAC labels proteins with stable isotopes to allow quantification, comparing labelled and unlabeled peptides for quantification. Pulse SILAC (pSILAC), only allows peptides created during the pulse to be labelled. In theory, this allows a capture of only nascent peptides for quantification. SILAC, however, requires similar levels of labelled and unlabelled proteins for accurate quantification. As such, pSILAC pulses have to run much longer than the translation process, making quantification of nascent peptides inaccurate.
Bio-Orthogonal/Quantitative Non-Canonical Amino acid Tagging
Bio-Orthogonal/Quantitative Non-Canonical Amino acid Tagging (BONCAT/QuaNCAT) uses azidohomoalanine (AHA) to tag proteins. This allows isolation of newly created proteins for MS. However, using AHA requires predepletion of intracellular methionine and introduction of AHA, stressing the cell and potentially altering translation dynamics within. Similar to pSILAC, AHA methods require longer pulses, thus limiting its efficacy in quantifying nascent peptides.
Puromycin-associated nascent chain proteomics
Puromycin-associated nascent chain proteomics (PUNCH-P) uses a puromycin-biotin label to capture nascent polypeptides for MS. Though it does not disturb the cell process, it is less sensitive than other methods in detecting nascent peptides. In addition to these quantification methods, other MS based methods are being worked on.
mRNA Degradation
Degradation of mRNA also plays an important part in regulating the translation process.
To explore mechanisms of decay, genome-wide mapping of uncapped and cleaved transcripts (GMUCT), parallel analysis of RNA ends (PARE), and degradome sequencing use the T4 ligase of the Illumina sequencing platform to sequence decapped mRNAs. T4 ligase ligates on RNA with a free 5’ monophosphate. As mature mRNAs have a 5’ cap, they are not bound as substrates, leaving decapped and degrading mRNAs to be bound.
5′-monophosphorylated ends sequencing (5Pseq) captures both capped and decapped sequences to allow sequencing of both mature mRNA and degraded products. This helps identify mRNA degradation products, and has uses in studying ribosome stalling.
These methods study 5’ to 3’ degradation, miRNA-mediated cleavage, and nonsense mediated mRNA decay, but cannot measure 3’ to 5’ degradation and other degradation mechanisms.
In Vivo Translation Tracking
The techniques above require lysis of cells and thus cannot be performed in living cells. Single molecule fluorescence resonance energy transfer (smFRET) and Nascent chain tracking (NCT) use fluorescence to track translational activity. Both methods track elongation rates of the polypeptides on single mRNAs. Neither technique, however, is capable of high throughput.
tRNAome
Transfer RNA (tRNA) is an important part of Translation. tRNAs read the mRNA, bringing the amino acids the ribosome assembles into a polypeptide. As such, the abundances and types of tRNAs has a large effect on the speed of protein synthesis. tRNAs can be very similar to other tRNAs, with some tRNA species only differing by a single nucleotide. This, coupled with similar secondary and tertiary structures makes separating different tRNA species difficult.
Gel Electrophoresis
2D-Gel electrophoresis is a classic method used in separating tRNAs. Initially, the tRNAs are denatured in 7M urea and separated in the first gel dimension. 4M urea allows partial refolding for additional separation in the second gel dimension. This method has allowed separation into 48 sets in E. coli and 30 in B. subtilis but has limited resolution. Large numbers of different tRNA species cannot be fully separated by 2D-gel electrophoresis, with only 62 spots found for the 269 rat tRNAs.
Liquid Chromatography
High performance liquid chromatography can be used to separate tRNAs based on aminoacylated tRNA isoacceptors. This method cannot fully separate the tRNA species and cannot distinguish between codons, though it still can find quantitative differences between different cell lines.
Mass Spectrometry
Mass spectrometry (MS) can be used to separate tRNAs based on unique endonuclease digestion products. This, however, has limited resolution with mixtures of 30 tRNA species and needs fractionation prior to MS in larger groups of tRNA. It also cannot be used to identify deNovo tRNA species as it requires prior knowledge of the digestion patterns of tRNA species.
Microarrays
Hybridization based microarrays use the 3’CCA conserved sequence in tRNAs to attach a fluorescent probe. 70-80 nucleotide long probes, covering the length of the tRNA, are then used to bind tRNAs. tRNAs with at least 8 base differences are able to be distinguished with microarrays, but tRNAs with smaller differences bind to the same probe.
Quantitative Reverse Transcription
Quantitative reverse transcription, real time PCR (qRT-PCR) is another way for identifying and quantifying the tRNAome. A primer for the conserved 3’CCA sequence is used for priming reverse transcription for all tRNA species. Heavy modification of the tRNA nucleotides and the stability of the tRNA molecule can be an issue, so high temperatures and demethylation have been used to counter these. Demethylation has also been used to counteract errors heavy methylation induces in sequencing.
Ribo-seq like
Ribo-tRNA-seq has been developed to observe the role of tRNA more closely to translation. Similar to Ribo-seq, Ribo-tRNA-seq captures tRNA molecules in ribosomes for library preparation before sequencing
See also
Degradomics
Proteomics
Translatome
References
Genomics
Bioinformatics | Translatomics | [
"Engineering",
"Biology"
] | 2,863 | [
"Bioinformatics",
"Biological engineering"
] |
66,821,593 | https://en.wikipedia.org/wiki/Microglossum%20olivaceum | Microglossum olivaceum (vernacular name: olive earthtongue) is a species of fungus belonging to the family Leotiaceae.
Synonym:
Geoglossum olivaceum Pers. (= basionym)
References
Leotiomycetes
Taxa named by Christiaan Hendrik Persoon
Fungus species | Microglossum olivaceum | [
"Biology"
] | 69 | [
"Fungi",
"Fungus species"
] |
66,823,220 | https://en.wikipedia.org/wiki/Timeline%20of%20Mars%202020 | The Mars 2020 mission, consisting of the rover Perseverance and helicopter Ingenuity, was launched on July 30, 2020, and landed in Jezero crater on Mars on February 18, 2021. As of , , Perseverance has been on the planet for sols ( total days; ). Ingenuity operated for sols ( total days; ) until its rotor blades, possibly all four, were damaged during the landing of flight 72 on January 18, 2024, causing NASA to retire the craft.
Current weather data on Mars is being monitored by the Curiosity rover and had previously been monitored by the Insight lander. The Perseverance rover is also collecting weather data. (See the External links section)
Overview of mission
Prelaunch (2012–2020)
The Mars 2020 mission was announced by NASA on December 4, 2012. In 2017 the three sites (Jezero crater, Northeastern Syrtis Major Planum, and Columbia Hills) were chosen as potential landing locations, with Jezero crater selected as the landing location, and launched on July 30th, 2020, from Cape Canaveral.
Landing and initial tests (February–May 2021)
After arriving on February 18, Perseverance focused on validating its systems. During this phase, it used its science instruments for the first time, generated oxygen on Mars with MOXIE, and deployed Ingenuity. Ingenuity began the technology demonstration phase of its mission, completing five flights before transitioning to the operations demonstration phase of its mission.
Cratered floor campaign (June 2021-April 2022)
The Cratered Floor Campaign was the first science campaign. It began on June 1, 2021, with the goal of exploring the Crater Floor Fractured Rough and Séítah geologic units. To avoid the sand dunes of the Séítah unit, Perseverance mostly traveled within the Crater Floor Fractured Rough geologic unit or along the boundary between the two units. The first nine of Perseverances sample tubes were to be filled during this expedition, including the first three 'witness tubes'.
After collecting the samples, Perseverance returned to its landing site, before continuing to the delta for its second science campaign. Some of the sample tubes filled during this campaign were later stored in a designated area for the upcoming NASA-ESA Mars Sample Return mission, during the Delta Front Campaign. While Perseverance embarked on its first science campaign, Ingenuity continued to travel alongside the rover as part of its operations demonstration campaign. Ingenuity's sixth through twenty-fifth flights were completed during this phase, achieving an at-the-time speed record of 5.5 meters per second.
Delta front campaign (April 2022 - January 2023)
The Delta Front Campaign was the second science campaign of the Mars 2020 mission. The campaign began with Ingenuity continuing to travel alongside the rover as part of its operations demonstration campaign, and Perseverance leaving the rapid traverse mode it had entered at the end of the last mission to rapidly reach the delta. During the campaign, Perseverance would take a further nine samples, in addition to two further witness tubes. Ingenuity would make its 41th flight during this mission. An incident occurred in which Ingenuity was unable to sufficiently charge during the night, leading to a change in how Ingenuity manages its heaters. The MOXIE experiment continued to run, generating a record amount of oxygen-per-hour on Mars. The campaign concluded with Perseverance reaching the top of the delta and the completion of its first sample depot.
Upper fan campaign (January 2023 - September 2023)
The Upper Fan Campaign, also called the Delta Top Campaign, was the third science campaign of the Mars 2020 mission. Whereas prior campaigns investigated areas that are believed to have been submerged in an ancient lake, this campaign investigated one of the riverbeds that used to feed into the lake. The MOXIE experiment completed its 16th, and final, oxygen generation test during this campaign. Ingenuity completed its 54th flight during this campaign. The helicopter experienced an anomaly that caused it to land outside the range of the rover, but this was ultimately resolved when the rover moved into a position that allowed contact to be restored. The campaign ended with Perseverance reaching the margin carbonate geologic unit, after having taken three further rock samples (and 21 overall).
Margin campaign (September 2023 - August 2024)
The Margin Campaign was the fourth of the Mars 2020 mission. The campaign was expected to last around 8 months, although it lasted closer to a year, after which point Perseverance began the Crater Rim Campaign. The campaign gets its name from the geological unit it aims to explore - the margin carbonate unit. Rocks in this unit are capable of containing traces of life, and their formation is tied to the presence of liquid water.
During the campaign, Ingenuity achieved several records, including a max altitude of 24 meters (flight 61) and a maximum groundspeed of 10 meters per second (flight 62). Unfortunately, due to a failure on the 72nd flight, the helicopter blades became too damaged to fly. On January 25th, 2024, NASA declared the end of Ingenuity's mission - the helicopter's final resting place was named Valinor Hills Station, after a location in the Lord of the Rings franchise. Despite the loss of Ingenuity's blades, the core of the helicopter remained intact; it will continue to monitor atmospheric conditions for as long as it is able. Perseverance took four further rock samples during this campaign (25 overall). The campaign overlapped with solar conjunction, interfering with the ability to communicate with the rover from Earth.
Engineers from NASA’s Jet Propulsion Laboratory in Southern California and AeroVironment are completing a detailed assessment of the Ingenuity Mars Helicopter’s final flight on January 18, 2024, the first of its kind on an extraterrestrial planet, concluding that the inability of Ingenuity’s navigation system to provide accurate data during the flight likely caused a chain of events that ended the mission.
The helicopter’s vision navigation system was designed to track visual features on the surface using a downward-looking camera over well-textured (pebbly) but flat terrain. This limited tracking capability was more than sufficient for carrying out Ingenuity’s first five flights, but by Flight 72 the helicopter was in a region of Jezero Crater filled with steep, relatively featureless sand ripples.
One of the navigation system’s main requirements was to provide velocity estimates that would enable the helicopter to land within a small envelope of vertical and horizontal velocities. Data sent down during Flight 72 shows that, around 20 seconds after takeoff, the navigation system couldn’t find enough surface features to track.
Photographs taken after the flight indicate the navigation errors created high horizontal velocities at touchdown. In the most likely scenario, the hard impact on the sand ripple’s slope caused Ingenuity to pitch and roll. The rapid attitude change resulted in loads on the fast-rotating rotor blades beyond their design limits, snapping all four of them off at their weakest point — about a third of the way from the tip. The damaged blades caused excessive vibration in the rotor system, ripping the remainder of one blade from its root and generating an excessive power demand that resulted in loss of communications.
Crater rim campaign (August 2024 - present)
The Crater Rim Campaign is the fifth, currently ongoing science campaign, and the first new science campaign since the loss of the Ingenuity helicopter. It is expected to last until the end of 2024, and will include a total elevation change of over 1000 feet (~300 meters). The main focuses of the campaign are expected to be at the regions "Pico Turquino" and "Witch Hazel Hill", pictured above. It is expected to encounter rocks as old as 4 billion years.
Samples cached for the Mars sample-return mission
In the frame of the NASA-ESA Mars Sample Return around of soil samples along with some Martian gas samples from the atmosphere will be cached. Currently, samples are being cached by Mars 2020 Perseverance Rover on the surface of Mars. Out of 43 sample tubes, 8 are igneous rock sample tubes, 12 are sedimentary rock sample tubes, 1 silica-cemented carbonate rock sample tube, 1 gas sample tube, 2 regolith sample tubes, 3 "witness tubes", with 16 tubes remaining unused as of August, 2024. Before launch, 5 of the 43 tubes were designated "witness tubes" and filled with materials that would capture particulates in the ambient environment of Mars.
See also
Astrobiology
Composition of Mars
Curiosity rover
Exploration of Mars
Geography of Mars
Geology of Mars
InSight lander
List of missions to Mars
List of rocks on Mars
Mars Exploration Rover
Mars Express orbiter
Mars Odyssey Orbiter
Mars Orbiter Mission
Mars Pathfinder (Sojourner rover)
Mars Reconnaissance Orbiter
Mars 2020 rover mission
MAVEN orbiter
Moons of Mars
Phoenix lander
Robotic spacecraft
Scientific information from the Mars Exploration Rover mission
Space exploration
Timeline of Mars Science Laboratory
U.S. Space Exploration History on U.S. Stamps
Viking program
Water on Mars
Notes
References
External links
Current Weather Report on Mars by the Perseverance rover – MEDA
(MarsWxReport/temp; 1st Report/6apr2021; NASA-1; NASA-2)
Mars Weather: Perseverance*Curiosity*InSight
Current Weather Report on Mars by the Curiosity rover
Current Weather Report on Mars by the InSight lander
Perseverance rover: Official website
Mars 2020: Official website
Mars 2020: Location Maps
(related site; 2GB PNG-image)
Video (60:00) – Minerals and the Origins of Life – (Robert Hazen; NASA; April 2014)
Video (86:49) – Search for Life in the Universe – (NASA; July 2014)
Video (13:33) – Mars Perseverance rover/Ingenuity helicopter report (9 May 2021; CBS-TV, 60 Minutes)
Video (03:04) − Exploring Jezero Crater − (NASA; December 2021)
Astrobiology
Exploration of Mars
Mars 2020
Articles containing video clips
2021 on Mars
Mars 2020 | Timeline of Mars 2020 | [
"Astronomy",
"Biology"
] | 2,076 | [
"Origin of life",
"Speculative evolution",
"Astrobiology",
"Biological hypotheses",
"Astronomical sub-disciplines"
] |
66,824,873 | https://en.wikipedia.org/wiki/Cold-stunning | Cold-stunning, also known as hypothermic stunning, is a hypothermic reaction experienced by marine reptiles, notably sea turtles, when exposed to cold water for prolonged periods, which causes them to become weak and inactive. Cold-stunned sea turtles may float to the surface and be further exposed to cold temperatures, which can cause them to drown. A water temperature threshold of 8–10 °C has been associated with mass turtle stunning events. After cold-stunning has taken place, there is only a very short period of time when sea turtles can be safely rescued.
One study indicates that ocean warming has led to an increase in cold-stunning events in the northwest Atlantic.
Notable instances
In 2016, 1,700 turtles were cold-stunned in North Carolina, following "an unusually temperate fall and early winter".
In 2021, nearly 5,000 cold-stunned turtles were rescued in Texas during a winter storm; it has been called the largest cold-stunning event to be documented in the state.
See also
Physiology of aquatic reptiles
References
Animal physiology
Animal welfare
Thermoregulation | Cold-stunning | [
"Biology"
] | 221 | [
"Thermoregulation",
"Animals",
"Animal physiology",
"Homeostasis"
] |
66,825,641 | https://en.wikipedia.org/wiki/Marek%20Strandberg | Marek Strandberg (born 25 September 1965 in Tallinn) is an Estonian materials scientist, businessman, caricaturist and politician. He has been member of XI Riigikogu.
He is a member of Estonian Greens.
References
1965 births
Living people
Estonian Greens politicians
Members of the Riigikogu, 2007–2011
Materials scientists and engineers
21st-century Estonian scientists
Estonian businesspeople
Estonian caricaturists
Politicians from Tallinn
Businesspeople from Tallinn
Scientists from Tallinn | Marek Strandberg | [
"Materials_science",
"Engineering"
] | 95 | [
"Materials scientists and engineers",
"Materials science"
] |
66,826,049 | https://en.wikipedia.org/wiki/AO%20Serpentis | AO Serpentis is an eclipsing binary star system in the Serpens Caput segment of the Serpens constellation. It is invisible to the naked eye with a typical apparent visual magnitude of 11.04. Variable star observers record a peak magnitude of 10.7, dropping to 12.0 during the primary eclipse and 10.8 from the secondary eclipse. The distance to this system is approximately 1,450 light years based on parallax measurements.
This system was discovered by C. Hoffmeister to be an Algol-type eclipsing binary in 1935. The following year, P. Guthnick and R. Prager reported a brightness variation between 10.5 and 12.0. In 2004, S. -L. Kim and associates determined that one of the components of this system is pulsating with a short period.
This is a semi-detached binary star system with the secondary component completely filling its Roche lobe while the primary is 61% full. It has an orbital period of and a semimajor axis of just 5.6 times the radius of the Sun. The orbital plane is inclined by an angle of 90° to the line of sight, causing the secondary component to be completely eclipsed once per orbit. The orbital period shows long-term cyclic variations, changing by up to 0.0051 days every 17.32 years. This may be due to magnetic activity cycles or the influence of a third body. The orbital period as a whole is steadily decreasing at the rate of due to loss of mass and angular momentum by the system.
The physical properties of the stellar components can be explained by a mass transfer. At some point in the past, mass flowed from the (at the time) more massive and evolved secondary component. This has left the primary as an A-type main-sequence star while the secondary is less massive but overly large. The hotter primary component is a Delta Scuti variable that is undergoing radial pulsation with a dominant frequency of 21.852 days−1 and a secondary frequency of 23.484 days−1.
References
A-type main-sequence stars
Algol variables
Delta Scuti variables
Eclipsing binaries
Serpens
Durchmusterung objects
Serpentis, AO | AO Serpentis | [
"Astronomy"
] | 457 | [
"Constellations",
"Serpens"
] |
66,826,136 | https://en.wikipedia.org/wiki/Catherine%20McCammon | Catherine Ann McCammon is a Canadian geoscientist who is employed by the University of Bayreuth. Her research focuses on surface and mantle processes, as well as the physics and chemistry of minerals. She is a Fellow of the European Association of Geochemistry and American Geophysical Union. In 2013, she was awarded the European Geosciences Union Robert Wilhelm Bunsen medal. She is the editor of the journal Physics and Chemistry of Minerals.
Early life and education
McCammon attended the Massachusetts Institute of Technology (MIT) for her undergraduate studies, where she majored in physics. She joined the American Geophysical Union as a member in 1978. She earned her doctorate at the Australian National University, where she studied the behaviour of iron oxides and sulphides. McCammon was a postdoctoral fellow with Natural Sciences and Engineering Research Council (NSERC) at the University of Manitoba.
Research and career
In 1985, McCammon moved to the University of British Columbia, first as a postdoctoral scholar and then as an assistant professor. She left Canada for the University of Bayreuth in 1990, where she was appointed to a permanent position in 1996. McCammon studies Earth materials using advanced spectroscopic techniques. In particular, McCammon makes use of X-ray emission, X-ray absorption and Mössbauer spectroscopy. She developed the Mössbauer milliprobe, which allows measurements of the Mössbauer spectra of objects with diameters below 500 μm. The milliprobe allows the characterisation of minerals in high-pressure environments as well as at various interfaces.
McCammon has investigated the characteristics of iron in high-pressure materials, measuring their oxidation states and spin transitions. Better understanding of the oxidation states of iron in deep regions of Earth's interior not only allows for accurate modelling of the formation of the core, but also provides insight into the planet's geochemical evolution. High pressure experimentation has helped McCammon to understand the cycling of oxygen on planet Earth and the effect of iron on mantle discontinuities and the conductivity of minerals. She is the editor of the journal Physics and Chemistry of Minerals.
Awards and honors
2001 Mineralogical Society of America Distinguished Lecturer
2002 Elected Fellow of the Mineralogical Society of America
2007 Elected Fellow of the European Association of Geochemistry
2007 Elected Fellow of the American Geophysical Union
2013 European Geosciences Union Robert Wilhelm Bunsen Medal
2017 International Board on the Applications of the Mössbauer Effect (IBAME) Science Award
2023 Harry H. Hess Medal of the American Geophysical Union
Selected publications
References
American women geologists
Academic staff of the University of Bayreuth
Fellows of the American Geophysical Union
Massachusetts Institute of Technology alumni
American academic journal editors
Australian National University alumni
American geochemists
American women inventors
Year of birth missing (living people)
Living people
American women academics
21st-century American women
Fellows of the Mineralogical Society of America | Catherine McCammon | [
"Chemistry"
] | 594 | [
"Geochemists",
"American geochemists"
] |
66,826,202 | https://en.wikipedia.org/wiki/Russula%20galbana | Russula galbana is a fungus in the family, Russulaceae, found in leaf litter in open forests of Allocasuarina littoralis and Eucalyptus tereticornis in Queensland.
It was first described in 2007 by Teresa Lebel and Jennifer Tonkin.
References
galbana
Taxa named by Teresa Lebel
Fungus species | Russula galbana | [
"Biology"
] | 67 | [
"Fungi",
"Fungus species"
] |
66,826,648 | https://en.wikipedia.org/wiki/Russula%20albidoflava | Russula albidoflava is a fungus in the family, Russulaceae, found "in stands of Eucalyptus globulus" in Tasmania.
It was first described in 2007 by Teresa Lebel and Jennifer Tonkin.
References
albidoflava
Taxa named by Teresa Lebel
Fungus species | Russula albidoflava | [
"Biology"
] | 63 | [
"Fungi",
"Fungus species"
] |
66,826,762 | https://en.wikipedia.org/wiki/Russula%20albobrunnea | Russula albobrunnea is a fungus in the family, Russulaceae, found Nothofagus forests (N. cunninghamii, N. moorei) of Queensland.
It was first described in 2007 by Teresa Lebel and Jennifer Tonkin.
References
albobrunnea
Taxa named by Teresa Lebel
Fungus species | Russula albobrunnea | [
"Biology"
] | 69 | [
"Fungi",
"Fungus species"
] |
66,826,817 | https://en.wikipedia.org/wiki/Russula%20brunneonigra | Russula brunneonigra is a fungus in the family Russulaceae, found Eucalyptus forests in New South Wales.
It was first described in 2007 by Teresa Lebel and Jennifer Tonkin.
References
brunneonigra
Taxa named by Teresa Lebel
Fungus species | Russula brunneonigra | [
"Biology"
] | 56 | [
"Fungi",
"Fungus species"
] |
66,826,869 | https://en.wikipedia.org/wiki/Russula%20pumicoidea | Russula pumicoidea is a fungus in the family, Russulaceae, found on sandy soils in Eucalyptus forests in Western Australia.
It was first described in 2007 by Teresa Lebel and Jennifer Tonkin.
References
pumicoidea
Taxa named by Teresa Lebel
Fungi described in 2007
Fungus species | Russula pumicoidea | [
"Biology"
] | 62 | [
"Fungi",
"Fungus species"
] |
66,826,973 | https://en.wikipedia.org/wiki/Russula%20reddellii | Russula reddellii is a fungus in the family, Russulaceae, found in leaf litter in "open,dry forests of Acacia, Allocasuarina, Eucalyptus, Lophostemon and Syncarpia" in Queensland.
It was first described in 2007 by Teresa Lebel and Jennifer Tonkin.
References
reddellii
Taxa named by Teresa Lebel
Fungi described in 2007
Fungus species | Russula reddellii | [
"Biology"
] | 81 | [
"Fungi",
"Fungus species"
] |
66,827,063 | https://en.wikipedia.org/wiki/Russula%20sinuata | Russula sinuata is a fungus in the family, Russulaceae, found in eucalyptus forests in Tasmania (E. angophoroides, E. gummifera and E. maculata).
It was first described in 2007 by Teresa Lebel and Jennifer Tonkin.
References
sinuata
Taxa named by Teresa Lebel
Fungi described in 2007
Fungus species | Russula sinuata | [
"Biology"
] | 75 | [
"Fungi",
"Fungus species"
] |
66,827,125 | https://en.wikipedia.org/wiki/Russula%20variispora | Russula variispora is a fungus in the family, Russulaceae, found in eucalypt forests in New South Wales.
It was first described in 2007 by Teresa Lebel and Jennifer Tonkin.
References
variispora
Taxa named by Teresa Lebel
Fungi described in 2007
Fungus species
Fungi of Australia | Russula variispora | [
"Biology"
] | 66 | [
"Fungi",
"Fungus species"
] |
66,827,268 | https://en.wikipedia.org/wiki/Russula%20agaricina | Russula agaricina is a fungus in the family, Russulaceae.
It was first described in 1876 as Macowania agaricina by Károly Kalchbrenner, and in 2007, based on phylogenetic evidence was transferred to the genus, Russula, by Teresa Lebel and Jennifer Tonkin (but invalidly published). The name, Russula agaricina was validly published in 2018 by James Trappe and Todd Elliott.
References
Taxa named by Miles Joseph Berkeley
agaricina
Fungus species | Russula agaricina | [
"Biology"
] | 107 | [
"Fungi",
"Fungus species"
] |
66,827,292 | https://en.wikipedia.org/wiki/Chromocyphella%20muscicola | Chromocyphella muscicola is a species of fungus in the family Hymenogastraceae. Basidiocarps (fruit bodies) are cyphelloid, cup-shaped, about 4 mm across, with an upper surface covered with fine hairs and a smooth underside.
It was first described as Cyphella muscicola by Elias Fries in 1822, and was transferred to the newly erected genus, Chromocyphylla, in 1959 by Marinus Anton Donk.
References
Agaricales
Taxa named by Elias Magnus Fries
Fungi described in 1822
Fungus species | Chromocyphella muscicola | [
"Biology"
] | 124 | [
"Fungi",
"Fungus species"
] |
75,449,928 | https://en.wikipedia.org/wiki/NGC%207541 | NGC 7541 is a barred spiral galaxy located around 104 million light-years away in the constellation Pisces. It was discovered in 1785 by William Herschel, and it is 106,000 light-years across. NGC 7541 is known to have lots of star-forming regions.
Characteristics
NGC 7541, like other barred spiral galaxies, has a bar in the center of it. The bar cuts through the center of the galaxy, and into the other side. This type of galaxy is known as "grand design". NGC 7541 is actually observed to have a higher-than-usual star formation rate, adding weight to the theory that spiral bars act as stellar nurseries, corralling and funneling inwards the material and fuel needed to create and nurture new baby stars. NGC 7541 also has an active galactic nuclei, as shown in the HST image.
NGC 7541 forms a pair with NGC 7537, a spiral galaxy 127 million light-years away, next to NGC 7541. The two galaxies have shown some signs of interaction, as two tidal tails form out of NGC 7541.
Supernovae
Two supernovae have been observed in NGC 7541:
SN 1998dh (typeIa, mag. 16.8) was discovered by the Lick Observatory Supernova Search (LOSS) on 20 July 1998.
SN 2017jmk (typeII, mag. ) was discovered by the Puckett Observatory Supernova Search (POSS) on 31 December 2017.
External links
References
Barred spiral galaxies
Pisces (constellation)
70795
12447
+01-59-017
Astronomical objects discovered in 1785
Galaxies discovered in 1785
Discoveries by William Herschel
7541 | NGC 7541 | [
"Astronomy"
] | 346 | [
"Pisces (constellation)",
"Constellations"
] |
75,452,067 | https://en.wikipedia.org/wiki/Tavis%E2%80%93Cummings%20model | In quantum optics, fhe Tavis–Cummings model is a theoretical model to describe an ensemble of identical two-level atoms coupled symmetrically to a single-mode quantized bosonic field. The model extends the Jaynes–Cummings model to larger spin numbers that represent collections of multiple atoms. It differs from the Dicke model in its use of the rotating-wave approximation to conserve the number of excitations of the system.
Originally introduced by Michael Tavis and Fred Cummings in 1968 to unify representations of atomic gases in electromagnetic fields under a single fully quantum Hamiltonian — as Robert Dicke had done previously using perturbation theory — the Tavis–Cummings model's restriction to a single field-mode with negligible counterrotating interactions simplifies the system's mathematics while preserving the breadth of its dynamics.
The model demonstrates superradiance, bright and dark states, Rabi oscillations and spontaneous emission, and other features of interest in quantum electrodynamics, quantum control and computation, atomic and molecular physics, and many-body physics. The model has been experimentally tested to determine the conditions of its viability, and realized in semiconducting and superconducting qubits.
Hamiltonian
The Tavis–Cummings model assumes that for the purposes of electromagnetic interactions, atomic structures are dominated by their dipole, as they are for distant neutral atoms in the weak-field limit. Thus the only atomic quantity under consideration is its angular momentum, not its position nor fine electronic structure. Furthermore, the model asserts the atoms to be sufficiently distant that they don't interact with each-other, only with the electromagnetic field, modeled as a bosonic field (since photons are the gauge bosons of electromagnetism).
Formal derivation
For two atomic-electronic states separated by a Bohr frequency , then transitions between the ground- and excited-states and are mediated by Pauli operators: , , and , and the Hamiltonian separating these energy states in the th atom is . With independent atoms each subject to this energy gap, the total atomic Hamiltonian is thus with total spin operators .
Similarly, in a free field with no modal restrictions, creation and annihilation operators dictate the presence of photons in each mode: with wave number , polarization , and frequency . If the dynamics occur within a sufficiently small cavity, only one mode (the cavity's resonant mode) will couple to the atom, thus the field Hamiltonian simplifies to , just as in the Jaynes-Cummings and Dicke models.thumb|Schematic diagram of the Tavis–Cummings physical model, representing an ensemble of two-level atoms (four dots on red and green levels) interacting symmetrically with a single mode photonic field (blue standing wave), isolated within a cavity. The atomic level separation is , the cavity's resonant frequency is , and the coupling strength of atom-field interactions is .|400x400px
Finally, interactions between atoms and the field is determined by the atomic dipole, rendered quantumly as an operator , and the similarly expressed electric field at the atoms' centers (assuming the field is the same at each atom's position) , thus which acts on both the qubit and bosonic degrees of freedom. The dipole operator couples the excited and ground states of each atom , while the electric free field solution is:
, which at a static point evaluates as:
, thus the interaction Hamiltonian expands as
.
Here, specifies the coupling strength of the total dipole to each electric field mode, and functioning as a Rabi frequency that scales with ensemble size due to the Pythagorean addition of single-atom dipoles. Then, in the rotating frame, , which results in corotating terms (representing photon absorption causing atomic excitation), (representing spontaneous emission), and counterrotating terms and (representing second-order effects like self-interaction and Lamb shifts). When and (close to resonance in a weak field), the corotating terms accumulate phase very slowly, while the counterrotating terms accumulate phase too fast to significantly affect time-ordered integrals, thus the rotating wave approximation allows counterrotating terms to drop in the rotating frame. The cavity permits only one field mode with energy sufficiently close to the Bohr energy, , so the final form of the interaction Hamiltonian is for dephasing .
In total, the Tavis–Cummings Hamiltonian includes the atomic and photonic self-energies and the atom-field interaction:
,
,
,
.
Symmetries
The Tavis–Cummings model as described above exhibits two symmetries arising from the Hamiltonian's commutation with excitation number and angular momentum magnitude . Since , it is possible to find simultaneous eigenstates such that:
,
,
.
The quantum number is bounded by , and , but due to the infinity of Fock space, excitation number is unbounded above, unlike angular momentum projection quantum numbers. Just as the Jaynes-Cummings Hamiltonian block-diagonalizes into infinite blocks of constant excitation number, the Tavis–Cummings Hamiltonian block-diagonlizes into infinite blocks of size up to with constant , and within these larger blocks, further block-diagonalizes into (usually degenerate) blocks of size where , with constant cooperation number . The size of each of these smallest blocks (irreps of SU(2)) determine the bounds of the final quantum number that specifies the eigenenergy: , with signifying the ground state of each irrep, and the maximally excited state.
Dynamics
Under the simplifications of real and quasistatically small , the Hamiltonian becomes , whose matrix elements one can express in a joint Dicke and Fock basis such that and . Necessarily, , so the matrix elements are as follows:
,
,
if , , or .
From these elements, one can express Schrödinger equations of motion to demonstrate the photon field's ability to mediate entanglement formation between atoms without atom-atom interactions: , for which the fine-tuned, multivariate dependence on quantum numbers demonstrates the difficulty of solving the Tavis-Cumming model's eigensystem. Here, a few approximate methods, and an exact solution involving Stark shifts and Kerr nonlinearities follow.
Spectrum approximations
In 1969, Tavis and Cummings found approximate eigenenergies and eigenstates for a nondimensionalized Hamiltonian in three different regimes of approximation: first, for near the ground-state of each irrep; second, for and when each atom sees a highly saturated "averaged" field; third, for with sparse excitations. In all solutions, eigenstates are related to Dicke-Fock joint states by , for coefficients that are solved from the Hamiltonian spectrum.
For close to zero, a differential approach provides the eigenvalues: with , average photon number , and differential coefficient .
For an averaged photon field when in a large photon-rich system, the off-diagonal matrix elements in (above) replace with , and each two-level atom interacts independently with a photon field that conveys no information about the other atoms. For each of these atoms, there are two dressed eigenstates coupled to "pseudophoton" number states: , with single-atom eigenenergies . Superpositions of these single-atom dressed states construct the full eigenstates according to addition of angular momenta, mediated by Clebsch-Gordan coefficients. The full eigenvalues are approximately .
For when the atomic ensemble, and not the photon field, is averaged, then the off-diagonal elements in approximate as , smearing over the atomic degrees of freedom in . Eigenstates are constructed as weighted superpositions of photon number states coupled to a spin state, but the eigenvalues are now.
Bethe ansatz
In 1996, Nikolay Bogoliubov (son of the 1992 Dirac Medalist of the same name), Robin Bullough, and Jussi Timonen found that adding quadratic excitation-dependent terms to the Tavis–Cummings Hamiltonian allowed for an exact analytic eigensystem. In the limit where these Kerr and Stark shifts vanish, this solution can recover the eigensystem of the unmodified Tavis–Cummings system.
Including a Kerr term of the form , or a Stark term equivalently results in a new Hamiltonian: , which obeys the same operator symmetries (above) as does the unmodified Tavis–Cummings Hamiltonian, and which reduces to Tavis–Cummings in the limit . Thus the transformation preserves the dynamics and shares joint eigenvectors with the untransformed Hamiltonian. The transformed Hamiltonian, explicitly, is for new parameters and , which is integrable using quantum inverse methods. Separating the dynamics into two complex-parametrized operator matrices (that is, matrices whose elements are operators), one acting on the bosonic degrees of freedom and the other on the spin degrees of freedom produces a monodromy matrix whose determinant is directly proportional to , whose trace is proportional to , and whose trace's parametric derivative is proportional to . Manipulating the monodromy matrix allows its spectral parameter to determine the Hamiltonian eigenstates and eigenenergies as the complex roots of a Bethe ansatz. Every for must satisfy the following Bethe equations:
,
then the Hamiltonian eigenvalues arise from the roots as:
.
In the limit where (and thus ), the above Bethe equations simplify to , and the eigenenergies to . Eigenstates follow similarly.
Experiments
The Tavis–Cummings model has seen numerous experimental implementations verifying its phenomena, including several since 2009 virtually realizing the model on quantum computational platforms like superconducting qubits and circuit QED. Such experiments utilize the Tavis–Cummings Hamiltonian's ability to generate superradiance wherein the artificial atoms emit and absorb light from the field coherently, as though they were a single atom with a large total angular momentum. Superradiance, scaling dipole-interaction strength , and other features allow Tavis–Cummings-type dynamics to manifest quantum computationally and metrologically desirable states, such as Dicke states (joint eigenstates of and ) through global interactions, as was explored in the 2003 paper by Tessier et al.
One realization by Tuchman et al., in 2006, used a stream of ultracold Rubidium-87 atoms (), and observed cooperation number , or 12% its maximum possible value, indicating very high interatomic coherence relative to experimental capabilities of the time. This experiment also confirmed the scaling of the dipole-interaction; at the level of single atoms, dipole interactions are much weaker than monopolar interactions, so the ability of Tavis–Cummings dynamics to counteract the weakness of with quadrature addition of dipoles makes neutral atom control more feasible.
Circuit QED
A seminal result from Fink et al. in 2009 involved 3 transmons as virtual "atoms" with qubit-dependent Bohr frequencies for controllable Josephson energy and experimentally determined single electron charging energy , inside a microwave waveguide resonator which supplies a standing electric field at GHz. To ensure symmetric coupling of the qubits to the field, each transmon was placed at an antinode of the standing wave, and to best conserve excitations by minimizing photon leakage, the resonator was kept ultracold (20mK) which ensured a high quality factor. Manipulating each qubit's Bohr frequency so only one qubit resonated with the field, the team measured each single-qubit coupling strength , then reintroduced the other qubits to compare the total coupling strength with the average strength of the resonating qubits, , confirming that . In addition, the team observed bright and dark states characterized by high emission rates and zero emissions respectively, for 2 and 3 active qubits, with the 3-qubit bright and dark states each being degenerate.
In addition to superconducting qubits, semiconducting qubits have also been a platform for Tavis–Cummings dynamics, such as in a 2018 investigation by van Woerkom et al. at ETH Zürich, in which two qubits constructed of double quantum dots (DQDs) coupled to a SQUID resonator, with the two DQDs separated by a distance of 42μm. The micrometer regime is a far greater distance than that over which semiconducting qubits had previously achieved entanglement, and the difficulty of long-range interactions in semiconducting qubits was at the time a major weakness compared to other quantum computing platforms, for which the Tavis–Cummings model's ability to form entanglement through global atom-field interactions is one solution. By observing the reflection amplitude of field waves between the SQUID array and the DQDs, the team isolated the photon number states as they smoothly coupled to the first qubit to form superpositional Jaynes-Cummings eigenstates when the first qubit tuned to the resonator. Similarly, they observed these hybrid states shift into a pair of bright states and a dark state (which did not interact with the light, and thus did not cause a dip in the reflection amplitude) when the second qubit was tuned to resonance. In addition to physical photons mediating the long-range entanglement at , the team found similar energy shifts at signalling qubits interacting with "virtual" photons, measured by the phase shift of the field rather than the reflection amplitude.
Limitations
Recent investigations by Johnson, Blaha, et al., have verified and explained two major regimes where the Tavis–Cummings model fails to predict physical reality, both following from systemic parameters approaching or exceeding the free spectral range based on the waveguide length . The violating quantities are the coupling strength , and the rate of photon-loss from atomic emissions into non-cavity modes, , where is the single-atom spontaneous-emission rate into all modes. When and , the Tavis–Cummings model well-describes the system, since the atom-light interactions are suppressed for all but one mode, and the field intensity is not significantly attenuated due to atomic emissions into other modes. However, when then the coupling enters the so-called "superstrong" regime and atom-light interactions must consider multiple field-modes. More severely, when then the atomic ensemble becomes optically thick, and the model must consider time-ordered interactions between the field and each atom, as atoms at the front of the ensemble will experience a more intense photonic wavefront than those at the back, due to the frontal atoms' absorptions and non-cavity mode emissions. This has the effect of interactions and correlations cascading successively across multiple atoms. As photons cross the waveguide and interact sequentially with the atoms in the ensemble, they accumulate phase at phenomenon-dependent rates. The total phase accumulated by electromagnetic waves in one round-trip of the waveguide may manifest resonances causing high transmission rates under specific dephasings and emission rates , and the locations of these resonances differs between the standard Tavis–Cummings model and the team's proposed "cascade" model. Using a fluid of ultracool Cesium atoms surrounding a nanofiber-section of a 30m fiber-ring resonator, the team coupled the atoms to the light passing through the nanofiber via an evanescent field, measuring the light's transmission for variable and , into the superstrong coupling and cascade regimes. The data from the nanofiber-Cesium experiment agreed better with the cascade model's predictions than with the Tavis–Cummings', specifically in the parametrically violating regimes above.
References
Quantum models
Quantum optics | Tavis–Cummings model | [
"Physics"
] | 3,293 | [
"Quantum models",
"Quantum optics",
"Quantum mechanics"
] |
75,452,164 | https://en.wikipedia.org/wiki/Taxman%20%28mathematical%20game%29 | Taxman, also known as Tax Factor, Number Shark, The Factor Game, Factor Blast, Factor Blaster, or Dr. Factor, is a mathematical game invented by mathematician Diane Resek.
Description
The game is played between two players on a board consisting of whole numbered tokens labeled 1 through N, where N is any positive whole number.
During each turn, one player (deemed the tax payer) takes a number from the board, and the other player (deemed the taxman) removes all remaining factors of the tax payer's number from the board.
The game ends when there are no legal moves left, and each player's score is calculated by adding up the values of the numbers they have collected. The player with the highest score wins.
Single-Player Version
In the single-player version, (Taxman, Tax Factor, Number Shark), the human player assumes the role of the tax payer each turn while the computer player is always the taxman.
In addition, the human player may only collect a number that still has proper factors remaining on the board. When there are no legal moves left, the taxman collects all of the remaining tokens on the board.
Two-Player Versions
In all two-player versions of the game, (The Factor Game, Factor Blast, Factor Blaster, Dr. Factor), the two players swap roles each turn, so that whoever is playing as the taxman during one turn will be the tax payer during the next turn, and vice versa.
In some versions, the tax payer may only collect a number that still has proper factors remaining on the board. If a player picks a number incorrectly, they may or may not lose their next turn, and they may or may not keep the number.
In some versions, the taxman may neglect to collect all of the factors of the tax payer's number, or may attempt to collect a factor incorrectly. The taxman may or may not lose points for missing factors or choosing incorrectly, and the tax payer may or may not be able to steal a factor that the taxman misses.
In some versions, there is the option to remove one or more numbers from the board before the game starts.
Origin and Spread
Taxman was invented by Resek sometime in the late 60's or early 70's while working at the Lawrence Hall of Science. It was published as a BASIC program in the September 1973 issue of the People's Computer Company Newsletter, and later appeared in the 1975 programming anthology book What to Do After You Hit Return.
In 1980, Taxman appeared as part of the software collection MECC - Elementary Volume 1 for the Apple II. The concept was later reused in other MECC titles, such as Wonderland Puzzles (as Hedgehog Croquet) and The Secret Island of Dr. Quandary (as Tax Factor) in 1992.
Starting in 1984, Taxman appeared as a coding exercise in a series of programming textbooks written by Lowell Carmony, a professor at Lake Forest College (and Berkeley alumnus). Carmony was part of the writing group for the 1993 NRC publication Measuring Up: Prototypes for Mathematics Assessment, which included Taxman as one of its prototypes. Carmony also described Taxman in an article for SIGCSE.
In 1996, a list of the best possible scores in Taxman, (called the Taxman sequence), was uploaded to the On-Line Encyclopedia of Integer Sequences. As of 2022, the sequence has been calculated out to a board size of 1000.
Around 2000, a version of Taxman was uploaded to the NRW's learn:line educational server under the name Der Zahlenhai (or Number Shark in English). A version of Number Shark was later added to CrypTool in 2006.
In 2015, Taxman appeared in the New York Times' Numberplay column as The Tax Collector.
Two-Player Versions
A two-player version of Taxman, known simply as The Factor Game, was described in an article for the November 1973 issue of The Arithmetic Teacher, a publication of the National Council of Teachers of Mathematics. The article was later reprinted in the 1975 anthology Games and Puzzles for Elementary and Middle School Mathematics.
In 1983, Factor Blast by Joe DeMuth was published by Hayden Software. Around 2000, educator Terry Kawas developed teaching materials for a similar variant called Factor Blaster which was later uploaded to Mathwire, a math education resource website.
In 1985, Dr. Factor appeared as one of four games in Playing To Learn by Antonia Stone, Joshua Abrams, and Ihor Charischak of HRM Software.
In 1986, another variant, also called The Factor Game, appeared as the first activity in the Factors and Multiples module of the Middle Grades Mathematics Project curriculum, and later appeared as part of the Connected Mathematics Project in 1996. Interactive versions were developed for Macintosh and Windows, and eventually a web version was developed for the NCTM's Illuminations website in 2001.
In Education
Taxman and its variants have been studied and used as tools in mathematics and computer science education.
Analysis
The winnability, strategy, and optimal score for the single-player version of Taxman have been studied.
References
External links
The Factor Game on the NCTM's Illuminations website
Mathematical games | Taxman (mathematical game) | [
"Mathematics"
] | 1,071 | [
"Recreational mathematics",
"Mathematical games"
] |
75,452,313 | https://en.wikipedia.org/wiki/Janet%20Perna | Janet Perna is a computer scientist known for her work in coordinating IBM's work in the field of databases.
Education and career
Perna grew up in Poughkeepsie, New York. She graduated with a degree in mathematics from SUNY Oneonta in 1970, and started teaching mathematics. In 1974 she moved to California and got a job at IBM as a programmer. She worked first in San Jose, and then moved to IBM's Santa Teresa Laboratory. She later moved to the data management division, and then the information management group. Projects she worked on included preparing the IBM Db2 for public release, and encouraging IBM's 2001 purchase of the database company Informix Corporation. Janet Perna was recognized as an industry leader for her contributions to IBM’s data management business. She played a crucial role in expanding IBM's data management into new, lucrative areas and setting industry standards. By 2001 she was the most senior female executive at IBM.
After 31 years at IBM, she decided to retire in 2006.
Honors and Awards
During her time at IBM, Janet was inducted into the Women In Technology International Hall of Fame, was recognized by Information Week as one of the nation's "Top 10 Women in IT," and included among the thinkers and innovators on Sm@rt Partner's list of "50 Smartest People".
Perna received an honorary degree from State University of New York at Oneonta in 2012.
In 2018, SUNY Oneota re-named a building the "Janet R. Perna Science Building".
In addition to these honors, Janet Perna has been recognized for her leadership in database management at IBM. She was named one of the “Top 50 Women to Watch” by Women in Technology International and received the "Leadership Award" from Computerworld. Additionally, eWeek awarded her the "Top 100 Most Influential People in IT" recognition. Her contributions were pivotal in IBM’s acquisition of Informix Corporation, further cementing her legacy in the tech industry.
References
External links
Living people
Computer scientists
IBM employees
State University of New York at Oneonta alumni
Business executives
Year of birth missing (living people) | Janet Perna | [
"Technology"
] | 439 | [
"Computer science",
"Computer scientists"
] |
75,452,565 | https://en.wikipedia.org/wiki/Brahmagupta%20polynomials | Brahmagupta polynomials are a class of polynomials associated with the Brahmagupa matrix which in turn is associated with the Brahmagupta's identity. The concept and terminology were introduced by E. R. Suryanarayan, University of Rhode Island, Kingston in a paper published in 1996. These polynomials have several interesting properties and have found applications in tiling problems and in the problem of finding Heronian triangles in which the lengths of the sides are consecutive integers.
Definition
Brahmagupta's identity
In algebra, Brahmagupta's identity says that, for given integer N, the product of two numbers of the form is again a number of the form. More precisely, we have
This identity can be used to generate infinitely many solutions to the Pell's equation. It can also be used to generate successively better rational approximations to square roots of arbitrary integers.
Brahmagupta matrix
If, for an arbitrary real number , we define the matrix
then, Brahmagupta's identity can be expressed in the following form:
The matrix is called the Brahmagupta matrix.
Brahmagupta polynomials
Let be as above. Then, it can be seen by induction that the matrix can be written in the form
Here, and are polynomials in . These polynomials are called the Brahmagupta polynomials. The first few of the polynomials are listed below:
Properties
A few elementary properties of the Brahmagupta polynomials are summarized here. More advanced properties are discussed in the paper by Suryanarayan.
Recurrence relations
The polynomials and satisfy the following recurrence relations:
Exact expressions
The eigenvalues of are and the corresponding eigenvectors are . Hence
.
It follows that
.
This yields the following exact expressions for and :
Expanding the powers in the above exact expressions using the binomial theorem and simplifying one gets the following expressions for and :
Special cases
If and then, for :
is the Fibonacci sequence .
is the Lucas sequence .
If we set and , then:
which are the numerators of continued fraction convergents to . This is also the sequence of half Pell-Lucas numbers.
which is the sequence of Pell numbers.
A differential equation
and are polynomial solutions of the following partial differential equation:
References
Polynomials
Homogeneous polynomials
Brahmagupta
Matrices | Brahmagupta polynomials | [
"Mathematics"
] | 472 | [
"Matrices (mathematics)",
"Polynomials",
"Mathematical objects",
"Algebra"
] |
75,453,455 | https://en.wikipedia.org/wiki/Cyclin%20E/Cdk2 | The Cyclin E/Cdk2 complex is a structure composed of two proteins, cyclin E and cyclin-dependent kinase 2 (Cdk2). Similar to other cyclin/Cdk complexes, the cyclin E/Cdk2 dimer plays a crucial role in regulating the cell cycle, with this specific complex peaking in activity during the G1/S transition. Once the cyclin and Cdk subunits join together, the complex gets activated, allowing it to phosphorylate and bind to downstream proteins to ultimately promote cell cycle progression. Although cyclin E can bind to other Cdk proteins, its primary binding partner is Cdk2, and the majority of cyclin E activity occurs when it exists as the cyclin E/Cdk2 complex.
G1/S transition
Across eukaryotic cell types, the cell cycle is highly conserved, and the cyclin/Cdk complexes are consistently essential in driving the entire process forwards. Shortly before the end of G1 phase, cyclin E joins with Cdk2 to activate its serine-threonine kinase activity and thus promote entry into S phase.
Eukaryotic cells possess two types of cyclin, cyclin E1 and cyclin E2, with the protein sequences sharing 69.3% similarity in humans despite being encoded by two different genes. While there is significant overlap in function between the two cyclin Es, there are distinct differences in the roles and regulation of each cyclin E type. For example, in Xenopus laevis embryos only cyclin E1 is necessary for viability.
In living cells, over-expression (an excess amount) of either cyclin E type results in an earlier activation of the cyclin E/Cdk2 complex and the subsequent shortening of G1 phase and thus accelerated movement into S phase. The cyclin E/Cdk2 complex is not only important in regulating the G1/S transition, but in fact necessary and sufficient, as cells lacking functional cyclin E are unable to enter S phase, remaining forever arrested in G1.
Complex activation
The cyclin E protein contains a section called the cyclin box, which interacts with the PSTAIRE helix on Cdk2 to enact a conformational change in Cdk2's T loop. The resulting exposure of Cdk2's catalytic site enables Cdk activating kinase (CAK) to phosphorylate Cdk2, allowing full activation of the cyclin E/Cdk2 complex. Once the protein dimer is formed and activated, it phosphorylates several important proteins including "proteins involved in centrosome duplication (NPM, CP110, Mps1), DNA synthesis (Cdt1), DNA repair (Brca1, Ku70), histone gene transcription (p220/NPAT, CBP/p300, HIRA) and Cdk inhibitors p21Waf1/Cip1 or p27Kip1." The complex interacts with its substrates due to two distinct regions of the cyclin E protein–the MRAIL and VDCLE domains. MRAIL is located at the N-terminus of cyclin E's cyclin box and interacts with proteins containing an RLX sequence (argininine-leucine-any amino acid) such as Rb, and p27KIP1. VDCLE is located at cyclin E's C-terminal region and interacts with proteins of the retinoblastoma family including Rb1, p107, and p130.
Localization
Cyclin E is predominantly found in the cell nucleus, and although it shuttles between the nucleus and the cytoplasm, it typically appears as a nuclear protein in images as its nuclear import is more rapid than its export. Cyclin E's nuclear localization sequence (NLS) allows the cyclin E/Cdk2 complex to readily enter the nucleus, although other mechanisms are believed to help the complex localize to the region as well. Cyclin E also contains a centrosome localization sequence (CLS) that plays a key role in allowing the cyclin E/Cdk2 complex to control centrosome duplication during early S phase.
Retinoblastoma protein
Background–phosphorylation
The retinoblastoma tumor suppressor protein (Rb) plays a key regulatory role in several cellular activities, such as the G1 restriction checkpoint, the DNA damage checkpoint, cell cycle exit, and cellular differentiation. As its full name suggests, cells containing mutations in pathways upstream of Rb or in the protein itself (however this case is more rare), are often cancerous. In fact, the majority of human cancer cells contain mutations in proteins responsible for phosphorylating Rb, such as deletions (p16) or over-expressions (cyclin D, Cdk4, Cdk6).
Within its structure, Rb contains 16 possible sites for phosphorylation by other proteins. Surprisingly, however, it exists in only 3 possible states: un-phosphorylated (no sites phosphorylated), mono-phosphorylated (one site phosphorylated), or hyper-phosphorylated (all available sites phosphorylated). In G0 phase, Rb exists solely in its un-phosphorylated form, but in early G1 phase, the Cyclin D:Cdk4/6 complex adds one phosphate group and the protein remains in its mono-phosphorylated form until late G1 when it is rapidly hyper-phosporylated by the Cyclin E/Cdk 2 complex.
Cell cycle progression
The key mechanism through which the cyclin E/Cdk2 complex is able to promote S phase progression is through Rb and E2F transcription factors. Transcription factors (TF) regulate the rate at which specific target genes are transcribed from DNA to RNA, i.e. transcription. At the end of G1, cells move through the restriction point–essentially "the point of no return" as cells that pass through are irreversibly committed to division and extracellular signals are no longer required for cell cycle progression. The rapid accumulation and activation of the cyclin E/Cdk 2 complex through positive feedback loops drives the cell forward through G1.
After phosphorylation by Cyclin D:Cdk4/6, mono-phosphorylated Rb binds to E2F family proteins, preventing their target genes from being transcribed; interestingly, one of the target genes is cyclin E. The rate-limiting switch-like step to initially activate the cyclin E/Cdk2 complex after Rb mono-phosphorylation is currently unknown, but it is hypothesized that the activation is regulated by an unidentified metabolic sensor, such that once the necessary metabolic threshold has been exceeded, the sensor activates Cyclin E/Cdk2. The metabolic sensor's activation of the cyclin E/Cdk2 complex initiates the process of Rb hyper-phosphorylation of Rb.
Mono-phosphorylated Rb inactivates E2F TFs, but hyper-phosphorylation of Rb results in Rb inactivation, causing the release of E2F proteins from the Rb binding cleft and consequent activation of the E2F family proteins to initiate transcription of their target genes. As a result, more cyclin E is transcribed and more cyclin E/Cdk2 complex is formed and activated. Thus, since cyclin E/Cdk2 activates its transcription factors, cyclin E/Cdk2 can facilitate its own activation, leading to a rapid accumulation of the complex and simultaneous rapid hyper-phosphorylation (i.e. inactivation) of Rb. The rapid inactivation of Rb causes a sudden switch-like transition through the late G1 restriction point (and into S phase). In summary, cyclin E/Cdk2's inactivation of Rb activates E2F which activates more cylin E (and thus the cyclin E/Cdk2 complex), creating a strong positive feedback loop that results in sudden inactivation of Rb and the irreversible push out of G1 and into S phase.
References
Cell cycle regulators | Cyclin E/Cdk2 | [
"Chemistry"
] | 1,792 | [
"Cell cycle regulators",
"Signal transduction"
] |
75,453,480 | https://en.wikipedia.org/wiki/%C3%97%20Tripleurocota | × Tripleurocota is a monotypic hybrid genus (nothogenus) in the family Asteraceae. Its only species is × Tripleurocota sulfurea, previously known as × Anthemi-matricaria sulfurea. Its native range is France and Yugoslavia. The species is a cross between Cota tinctoria and Tripleurospermum inodorum. The nothogenus was established in 2005 by Walter Karl Starmühler.
References
Intergeneric hybrids
Flora of Yugoslavia
Flora of France
Monotypic Asteraceae genera | × Tripleurocota | [
"Biology"
] | 112 | [
"Intergeneric hybrids",
"Hybrid organisms"
] |
75,453,881 | https://en.wikipedia.org/wiki/Prusogliptin | Prusogliptin (DBPR108) is an experimental DPP-4 inhibitor developed by CSPC Pharmaceutical Group to treat type 2 diabetes.
References
Dipeptidyl peptidase-4 inhibitors
Nitriles
Pyrrolidines
Organofluorides
Carboxamides
Secondary amines | Prusogliptin | [
"Chemistry"
] | 65 | [
"Nitriles",
"Functional groups"
] |
75,453,920 | https://en.wikipedia.org/wiki/Globalagliatin | Globalagliatin (SY-004) is a glucokinase activator developed by Yabao Pharmaceutical Group for type 2 diabetes.
References
Experimental diabetes drugs
Pyrrolidines
Thioethers
Thiazoles
Cyclopropyl compounds
Sulfones | Globalagliatin | [
"Chemistry"
] | 60 | [
"Sulfones",
"Functional groups"
] |
75,455,894 | https://en.wikipedia.org/wiki/Xiaomi%20Pad%206 | The Xiaomi Pad 6 is a line of mid-range to high end tablets manufactured by Xiaomi. These 3 tablets were introduced in China in 2023 while Xiaomi Pad 6 was released globally as well. All these tablets are equipped with Qualcomm's 8 Series Snapdragon Chipset. A newer version, Xiaomi Pad 6S Pro 12.4 was also released in 2024 which packs better specifications and bigger display for the Global Markets. With these tablets, Xiaomi also released accessories like Folio Case, Keyboard attachment as well as Xiaomi's 2nd Generation Smart Pen.
The tablets also received update to Xiaomi's new Xiaomi HyperOS based on Android 14 in 2024.
References
Tablet computers
Xiaomi products | Xiaomi Pad 6 | [
"Technology"
] | 152 | [
"Mobile computer stubs",
"Mobile technology stubs"
] |
75,457,375 | https://en.wikipedia.org/wiki/The%20New%20Politics%20of%20Numbers | The New Politics of Numbers: Utopia, evidence and democracy is a multi-author book edited by sociologists Andrea Mennicken and Robert Salais and published in 2022 by Palgrave Macmillan.
Synopsis
This work connects to the 1989 volume The Politics of Numbers of William Alonso and Paul Starr, as well to the French school of sociology of quantification of Alain Desrosières’ The Politics of Large Numbers, Laurent Thévenot, the same Robert Salais, and other scholars in France and the UK. The volume sets out to investigate the power of numbers, how they travel across countries and domains, how they may be implicated in dreams of making things differently and creating new worlds, and how they establish new regimes of accountability and regulation. The book devotes particular attention to the linkages between numbers and democracy.
The book was inspired by a working group on social quantification at the Wissenschaftskolleg zu Berlin in 2014. It is inspired by two strands of research: one related to Foucauldian ideas of power and control, which were studied by historians and sociologists at the London School of Economics; and the other being the "economics of conventions" or "theory of conventions", studied by various French scholars, including Luc Boltanski, Laurent Thévenot, and originally by Alain Desrosières.
Content
The chapter of Peter Miller investigates the role of numbers in the making of health policies. The role of quantification in the making of international certification standards is discussed by Thévenot. Uwe Vormbusch provides an account of the movement of the quantified self, while Boris Samuel provides an example of Statactivism staged in French Guadeloupe. Ota De Leonardis discusses how numbers permit a semantic shift in the meaning of inequality. The book also contains chapters from other scholars such as Emmanuel Didier, Martine Mespoulet, Tom Lang, Corine Eyraud and others. Wendy Nelson Espeland writes the foreword "What Numbers Do".
Reception
Harro Maas writes that "it is just impossible to open a newspaper or news site without being reminded of the themes addressed in this volume" after having read the book.
Related readings
Alain Desrosières, The Politics of Large Numbers: a history of statistical reasoning, Harvard University Press (1998).
Alonso, W., & Starr, P. (1989). The Politics of Numbers, Russell Sage Foundation.
Bessy, C., & Didry, C. (Eds.). (2022). L’économie est une science réflexive, Chômage, convention et capacité dans l’œuvre de Robert Salais, Presses Universitaires du Septentrion.
Theodore M. Porter, Trust in Numbers: The Pursuit of Objectivity in Science and Public Life, Princeton University Press, 1995.
See also
Sociology of quantification
References
2022 non-fiction books
French non-fiction books
History books about science
History of probability and statistics
Science and technology studies | The New Politics of Numbers | [
"Mathematics",
"Technology"
] | 621 | [
"Probability and statistics",
"Science and technology studies",
"History of probability and statistics"
] |
75,457,464 | https://en.wikipedia.org/wiki/Pramlintide/insulin%20A21G | Pramlintide/insulin A21G (development name ADO09) is a combination of the amylin analogue pramlintide and an insulin analog. It is being developed by Adocia for diabetes.
References
Combination diabetes drugs
Insulin receptor agonists
Amylin receptor agonists
Experimental diabetes drugs | Pramlintide/insulin A21G | [
"Chemistry"
] | 67 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
75,457,538 | https://en.wikipedia.org/wiki/Volagidemab | Volagidemab (development name REMD-477) is a monoclonal antibody that targets the glucagon receptor. It is developed by REMD Biotherapeutics for type 1 and type 2 diabetes. A phase II trial did not meet its primary endpoint.
Research
A systematic review and meta-analysis of volagidemab, published in 2024, found it to be potentially beneficial in the treatment of type1 diabetes.
References
Experimental diabetes drugs
Glucagon receptor antagonists
Monoclonal antibodies | Volagidemab | [
"Chemistry"
] | 111 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
75,457,600 | https://en.wikipedia.org/wiki/Insulin%20tregopil | Insulin tregopil is a fast-acting insulin analog, unlike other forms of insulin it is delivered by mouth. It is developed by Biocon for diabetes.
References
Insulin receptor agonists | Insulin tregopil | [
"Chemistry"
] | 41 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
75,457,814 | https://en.wikipedia.org/wiki/XEN-D0501 | XEN-D0501 is an experimental transient receptor potential vanilloid 1 (TRPV1) antagonist. It was acquired by Pila Pharma from Ario Pharma in 2016.
References
Receptor antagonists | XEN-D0501 | [
"Chemistry"
] | 49 | [
"Neurochemistry",
"Receptor antagonists"
] |
75,458,034 | https://en.wikipedia.org/wiki/Buzzer%20%28internet%29 | Buzzer () is an Indonesian term used to refer to a person who works to "buzz" certain message or perspective in regards to a certain issue, opinion, or brand, in order to make the opinion as natural as possible. Buzzer attempts to influence public opinion to align with their cause. Scholars have differing opinion in how one should be regarded as buzzers in terms of their use of accounts: some argue buzzers exclusively refer to sockpuppet operators; while others argue that buzzers may use influencer accounts, if not both. Scholars also differ in terms of compensation: some argue that buzzers refer only to those paid by money (then known as buzzeRp); while others argue that buzzers can have non-monetary compensation such as position, social relations, patronage, as well as conviction and commitment to the cause.
Buzzers who are involved in the propagation of perspective related to elections, political party, as well as contentious government and corporate policies are often referred to as political buzzer ().
See also
50 Cent Party
State-sponsored Internet propaganda
Fake news
Troll
Astroturfing
References
Internet terminology
Cyberwarfare
Internet manipulation and propaganda | Buzzer (internet) | [
"Technology"
] | 234 | [
"Computing terminology",
"Internet terminology"
] |
75,458,259 | https://en.wikipedia.org/wiki/IMCY-0098 | IMCY-0098 is a peptide immunotherapy based on proinsulin and developed by Imcyse to reduce the progression of type 1 diabetes.
References
Peptide therapeutics
Immunotherapy
Experimental diabetes drugs | IMCY-0098 | [
"Chemistry"
] | 48 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
75,459,235 | https://en.wikipedia.org/wiki/C%20Bounded%20Model%20Checker | In the context of computer science, the C Bounded Model Checker (CBMC) is a bounded model checker for C programs. It was the first such tool.
CBMC has participated in the Competition on Software Verification (SV-COMP) in the years 2014–2022. It came in first in at least one category in 2014, 2015, and 2017.
Applications
CBMC has been used to verify C code at Amazon Web Services. It is used as model checker in the Kani and Crust verifiers for Rust, and the JBMC bounded model checker for Java.
References
External links
Formal methods tools
Static program analysis tools
Software testing tools | C Bounded Model Checker | [
"Mathematics"
] | 137 | [
"Formal methods tools",
"Mathematical software"
] |
75,459,758 | https://en.wikipedia.org/wiki/Cyanosulfidic%20prebiotic%20synthesis | Cyanosulfidic prebiotic synthesis is a proposed mechanism for the origin of the key chemical building blocks of life. It involves a systems chemistry approach to synthesize the precursors of amino acids, ribonucleotides, and lipids using the same starting reagents and largely the same plausible early Earth conditions. Cyanosulfidic prebiotic synthesis was developed by John Sutherland and co-workers at the Laboratory of Molecular Biology in Cambridge, England.
Challenges
Prebiotic synthesis of amino acids, nucleobases, lipids, and other building blocks of protocells and metabolisms is still poorly understood. Proposed reactions that produce individual components such as the Strecker synthesis of amino acids, the formose reaction for the production of sugars, and prebiotic syntheses for the production of nucleobases. These syntheses often rely on different starting reagents, different conditions (temperature, pH, catalysts, etc.), and often will interfere with each other. These challenges have made determining the conditions for the origin of life difficult. Researchers have turned to systems chemistry type approaches to help overcome some of these challenges. Systems chemistry approaches form multiple products form a single synthesis under the same conditions and tend to be more similar to biological processes in that they have emergent properties, self-organization, and autocatalysis. Cyanosulfidic prebiotic synthesis is a systems chemistry approach.
Mechanism
The starting reactants for these reactions are hydrogen cyanide (HCN) as well as HCN derivatives and acetylene. Both of these are hypothesized to be present on the early Earth. The conditions this reaction occurs in are a relatively moderate temperature of 35 degrees C and in anoxic or oxygen free conditions. The early Earth was anoxic before the great oxidation event, making these conditions plausible. In the laboratory synthesis, a neutral phosphate buffer was used to maintain a stable, neutral pH. hydrogen sulfide (H2S) is used as a reductant in these reactions. The reactions are driven forward by ultraviolet radiation and catalyzed by Cu(I)-Cu(II) photoredox cycling. Some compounds in the system perform multiple roles. For example, phosphate serves as a buffer to maintain a neutral pH, acts as a catalyst in the synthesis of 2-aminooxazole and urea and serves as a reagent in the formation of glycerol-3-phosphate and ribonucleotides. The mechanisms involved in these reactions include reductive homologation processes to build larger, more complex molecules from the simple starting materials. The products of this reaction include the precursors of many amino acids, the precursors of lipids, and ribonucleotides. It is worth noting that most of the prebiotic monomers are not synthesized in their entirety by these reactions, only their precursors. The amino acid precursors would then be produced by Strecker synthesis reactions. Cyanosulfidic metabolism also does produce the precursors of both purines and pyrimidines ribonucleotides simultaneously. Many of the compounds produced also include intermediates in one-carbon metabolism.
Geochemical context
Sutherland and collaborators proposed a geochemical scenario to argue that cyanosulfidic synthesis was a plausible process on the early Earth. Their scenario starts following a meteorite impact leads to the production of HCN and phosphate. The meteorite fragments also supply the necessary sulfide for the reaction. As ponds and lakes containing these reagents experience wet dry cycles, ferrocyanide, sodium, and potassium salts precipitate out of solution into evaporites, concentrating and storing reactants for future chemistry. These evaporites can then be thermally altered through additional impacts or geothermal heating, producing all necessary components for the proposed syntheses. Rain and runoff create streams that transport compounds along geochemical gradients, introducing new reactants along the way which causes new syntheses to occur. The streams are also exposed to ultraviolet radiation, providing energy for the reactions. The conditions described here support an evaporative lake or terrestrial hydrothermal pond scenario for the origin of life. The proposed geochemical scenario also relies on flow chemistry concepts to introduce new reactants throughout the process to cause additional chemical reactions and syntheses to occur.
Limitations
Cyanosulfidic chemistry has several limitations. While the products are all formed from the same starting materials, many of the reactions require the periodic delivery of new reagents which complicates the syntheses. The chemical synthesis is therefore not truly “one-pot” chemistry which would require all reactants to be provided at the beginning which no further alterations. Sutherland and colleagues argue that a “flow-chemistry” approach featuring the movement of compounds through a stream experiencing different geochemical conditions makes their proposed system plausible.
Variants
Other challenges of the cyanosulfidic prebiotic synthesis approach is that the reductant, sulfide, has low solubility in water except in alkaline conditions and the main catalyst, copper, has a relatively low abundance in Earth’s crust. To address these problems, an alternative scheme for prebiotic systems chemistry called cyanosulfitic prebiotic synthesis has been proposed. These set of reactions relies on sulfite instead of sulfide, and ferrocyanide to catalyze reactions when exposed to ultraviolet light. The products of these reactions rely on similar chemistry to cyanofidic mechanisms such as reductive homologation and produce similar products such as amino acid precursors as well as sugars and hydroxy acids. Both sulfite (from sulfur dioxide released by volcanos) and ferrous iron (FeII) are hypothesized to have been present in high quantities on the early Earth, suggesting that this is potentially a much for feasible set of reactions.
References
Prebiotic chemistry | Cyanosulfidic prebiotic synthesis | [
"Chemistry",
"Biology"
] | 1,208 | [
"Biological hypotheses",
"Origin of life",
"Prebiotic chemistry"
] |
75,460,161 | https://en.wikipedia.org/wiki/Linear%20biochemical%20pathway | A linear biochemical pathway is a chain of enzyme-catalyzed reaction steps where the product of one reaction becomes the substrate for the next reaction. The molecules progress through the pathway sequentially from the starting substrate to the final product. Each step in the pathway is usually facilitated by a different specific enzyme that catalyzes the chemical transformation. An example includes DNA replication, which connects the starting substrate and the end product in a straightforward sequence.
Biological cells consume nutrients to sustain life. These nutrients are broken down to smaller molecules. Some of the molecules are used in the cells for various biological functions, and others are reassembled into more complex structures required for life. The breakdown and reassembly of nutrients is called metabolism. An individual cell contains thousands of different kinds of small molecules, such as sugars, lipids, and amino acids. The interconversion of these molecules is carried out by catalysts called enzymes. For example, the most widely studied bacterium, E. coli strain K-12, is able to produce about 2,338 metabolic enzymes. These enzymes collectively form a complex web of reactions comprising pathways by which substrates (including nutients and intermediates) are converted to products (other intermediates and end-products).
The figure below shows a four step pathway, with intermediates, and . To sustain a steady-state, the boundary species and are fixed. Each step is catalyzed by an enzyme, .
Linear pathways follow a step-by-step sequence, where each enzymatic reaction results in the transformation of a substrate into an intermediate product. This intermediate is processed by subsequent enzymes until the final product is synthesized.
A linear pathway can be studied in various ways. Multiple computer simulations can be run to try to understand the pathway's behavior. Another way to understand the properties of a linear pathway is to take a more analytical approach. Analytical solutions can be derived for the steady-state if simple mass-action kinetics are assumed. Analytical solutions for the steady-state when assuming Michaelis-Menten kinetics can be obtained but are quite often avoided. Instead, such models are linearized. The three approaches that are usually used are therefore:
Computer simulation
Analytical solutions using a linear mathematical model
Linearization of a non-linear model
Computer simulation
It is possible to build a computer simulation of a linear biochemical pathway. This can be done by building a simple model that describes each intermediate through a differential equation. The differential equations can be written by invoking mass conservation. For example, for the linear pathway:
where and are fixed boundary species, the non-fixed intermediate can be described using the differential equation:
The rate of change of the non-fixed intermediates and can be written in the same way:
To run a simulation the rates, need to be defined. If mass-action kinetics are assumed for the reaction rates, then the differential equation can be written as:
If values are assigned to the rate constants, , and the fixed species and the differential equations can be solved.
Analytical solutions
Computer simulations can only yield so much insight, as one would be required to run simulations on a wide range of parameter values, which can be unwieldy. A generally more powerful way to understand the properties of a model is to solve the differential equations analytically.
Analytical solutions are possible if simple mass-action kinetics on each reaction step are assumed:
where and are the forward and reverse rate-constants, respectively. is the substrate and the product. If the equilibrium constant for this reaction is:
The mass-action kinetic equation can be modified to be:
Given the reaction rates, the differential equations describing the rates of change of the species can be described. For example, the rate of change of will equal:
By setting the differential equations to zero, the steady-state concentration for the species can be derived. From here, the pathway flux equation can be determined. For the three-step pathway, the steady-state concentrations of and are given by:
Inserting either or into one of the rate laws will give the steady-state pathway flux, :
A pattern can be seen in this equation such that, in general, for a linear pathway of steps, the steady-state pathway flux is given by:
Note that the pathway flux is a function of all the kinetic and thermodynamic parameters. This means there is no single parameter that determines the flux completely. If is equated to enzyme activity, then every enzyme in the pathway has some influence over the flux.
Linearized model: deriving control coefficients
Given the flux expression, it is possible to derive the flux control coefficients by differentiation and scaling of the flux expression. This can be done for the general case of steps:
This result yields two corollaries:
The sum of the flux control coefficients is one. This confirms the summation theorem.
The value of an individual flux control coefficient in a linear reaction chain is greater than 0 or less than one:
For the three-step linear chain, the flux control coefficients are given by:
where is given by:
Given these results, there are some patterns:
If all three steps have large equilibrium constants, that is , then tends to one and the remaining coefficients tend to zero.
If the equilibrium constants are smaller, control tends to get distributed across all three steps.
With more moderate equilibrium constants, perturbations can travel upstream as well as downstream. For example, a perturbation at the last step, , is better able to influence the reaction rates upstream, which results in an alteration in the steady-state flux.
An important result can be obtained if all are set as equal to each other. Under these conditions, the flux control coefficient is proportional to the numerator. That is:
If it is assumed that the equilibrium constants are all greater than 1.0, as earlier steps have more terms, it must mean that earlier steps will, in general, have high larger flux control coefficients. In a linear chain of reaction steps, flux control will tend to be biased towards the front of the pathway. From a metabolic engineering or drug-targeting perspective, preference should be given to targeting the earlier steps in a pathway since they have the greatest effect on pathway flux. Note that this rule only applies to pathways without negative feedback loops.
References
Metabolic pathways
Biochemistry
Enzyme kinetics
Metabolism | Linear biochemical pathway | [
"Chemistry",
"Biology"
] | 1,282 | [
"Biochemistry",
"Enzyme kinetics",
"Cellular processes",
"nan",
"Metabolic pathways",
"Chemical kinetics",
"Metabolism"
] |
75,460,257 | https://en.wikipedia.org/wiki/Narayana%20polynomials | Narayana polynomials are a class of polynomials whose coefficients are the Narayana numbers. The Narayana numbers and Narayana polynomials are named after the Canadian mathematician T. V. Narayana (1930–1987). They appear in several combinatorial problems.
Definitions
For a positive integer and for an integer , the Narayana number is defined by
The number is defined as for and as for .
For a nonnegative integer , the -th Narayana polynomial is defined by
The associated Narayana polynomial is defined as the reciprocal polynomial of :
.
Examples
The first few Narayana polynomials are
Properties
A few of the properties of the Narayana polynomials and the associated Narayana polynomials are collected below. Further information on the properties of these polynomials are available in the references cited.
Alternative form of the Narayana polynomials
The Narayana polynomials can be expressed in the following alternative form:
Special values
is the -th Catalan number . The first few Catalan numbers are . .
is the -th large Schröder number. This is the number of plane trees having edges with leaves colored by one of two colors. The first few Schröder numbers are . .
For integers , let denote the number of underdiagonal paths from to in a grid having step set . Then .
Recurrence relations
For , satisfies the following nonlinear recurrence relation:
.
For , satisfies the following second order linear recurrence relation:
with and .
Generating function
The ordinary generating function the Narayana polynomials is given by
Integral representation
The -th degree Legendre polynomial is given by
Then, for n > 0, the Narayana polynomial can be expressed in the following form:
.
See also
Catalan number
Schröder number
References
Polynomials | Narayana polynomials | [
"Mathematics"
] | 343 | [
"Polynomials",
"Algebra"
] |
75,460,492 | https://en.wikipedia.org/wiki/1-Boc-4-AP | 1-Boc-4-AP (tert-butyl 4-(phenylamino)piperidine-1-carboxylate) is a compound used as an intermediate in the manufacture of fentanyl, as well as various related derivatives such as butyrylfentanyl, furanylfentanyl, benzylfentanyl and homofentanyl, among others. It is an N-protected derivative of 4-anilinopiperidine which can be readily converted to fentanyl or related analogues in several straightforward synthetic steps. It was classified as a DEA List 1 Chemical in 2022, and is also controlled in various other jurisdictions. Its possession, sale and importation are consequently heavily regulated throughout much of the world. 1-Boc-4-AP has also been identified as an impurity in other designer drug products, though it is unclear if it has any pharmacological activity in its own right.
See also
4-ANPP
4-Piperidone
N-Phenethyl-4-piperidinone
N-t-BOC-MDMA
1-(2-Chloro-N-methylbenzimidoyl)cyclopentanol
References
Piperidines
Anilines
Tert-butyl compounds
Formamides
Amines | 1-Boc-4-AP | [
"Chemistry"
] | 275 | [
"Amines",
"Bases (chemistry)",
"Functional groups"
] |
75,461,427 | https://en.wikipedia.org/wiki/Cadisegliatin | Cadisegliatin (TTP399) is a liver-selective glucokinase activator. It is being developed by VTV Therapeutics for treatment of type 2 diabetes or type 1 diabetes as an adjunct to insulin.
References
Small-molecule drugs
Cyclohexylamines
Ureas
Thiazoles
Acetic acids
Thioethers
Propyl compounds | Cadisegliatin | [
"Chemistry"
] | 80 | [
"Organic compounds",
"Ureas"
] |
75,461,692 | https://en.wikipedia.org/wiki/Glycopegylation | Glycopegylation "is a site-selective PEGylation method developed for modifying complex glycoproteins". It can be useful to improve bioavailability and extend the half-life of various therapeutic proteins. Examples of glycopegylated molecules include pegozafermin and recombinant factor IX.
References
Pharmacokinetics
Biotechnology | Glycopegylation | [
"Chemistry",
"Biology"
] | 79 | [
"Pharmacology",
"Pharmacokinetics",
"Biotechnology stubs",
"Biotechnology",
"nan"
] |
75,461,750 | https://en.wikipedia.org/wiki/Pegozafermin | Pegozafermin (BIO89-100) is a long-acting, glycopegylated FGF21 analog developed for the treatment of nonalcoholic steatohepatitis and hypertriglyceridemia.
References
Biopharmaceuticals
Fibroblast growth factor 21 analogs | Pegozafermin | [
"Chemistry",
"Biology"
] | 68 | [
"Pharmacology",
"Biotechnology products",
"Medicinal chemistry stubs",
"Pharmacology stubs",
"Biopharmaceuticals"
] |
75,462,137 | https://en.wikipedia.org/wiki/PXL065 | PXL065 (d-R-pioglitazone) is a drug candidate for the treatment of nonalcoholic steatohepatitis (NASH). It is the deuterium-stabilized (R)-enantiomer of pioglitazone which lacks PPARγ agonist activity and the associated side effects of weight gain and edema. PXL065 (formerly known as DRX-065) has demonstrated preclinical efficacy for both NASH and X-linked adrenoleukodystrophy (X-ALD). In 2022, it successfully completed a 9 month Phase 2 trial in biopsy-proven NASH patients where it met the primary endpoint for reduction in liver fat without weight gain or edema.
PXL065 was discovered and advanced to Phase 1 by DeuteRx, LLC using the strategy of deuterium-enabled chiral switching (DECS). In August 2018, PXL065 and a portfolio of deuterated thiazolidinediones (TZDs) was acquired by Poxel SA.
Notes
References
Experimental drugs developed for non-alcoholic fatty liver disease
Thiazolidinediones
Deuterated compounds
Phenol ethers
Pyridines
Ethyl compounds | PXL065 | [
"Chemistry"
] | 269 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
75,462,376 | https://en.wikipedia.org/wiki/ASC41 | ASC41 is a thyromimetic prodrug metabolized in the liver by CYP3A4 to an active form, ASC41-A, that is selective for thyroid hormone receptor beta. It is developed for non-alcoholic fatty liver disease. In 2023, Viking Therapeutics filed a lawsuit against ASC41's developer, Chinese company Ascletis BioScience, accusing it of stealing Viking's trade secrets to develop ASC41 which is allegedly similar to, or identical to, VK2809.
References
Prodrugs
Thyroid hormone receptor beta agonists | ASC41 | [
"Chemistry"
] | 126 | [
"Chemicals in medicine",
"Prodrugs"
] |
75,462,783 | https://en.wikipedia.org/wiki/JKB-122 | JKB-122 is an investigational small molecule, long-acting toll-like receptor 4 (TLR4) antagonist developed for autoimmune hepatitis and nonalcoholic fatty liver disease. The drug was transferred to Biostax in 2022.
References
Receptor antagonists
Small-molecule drugs
Experimental drugs | JKB-122 | [
"Chemistry"
] | 67 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs",
"Receptor antagonists",
"Neurochemistry"
] |
75,463,818 | https://en.wikipedia.org/wiki/Quasi-isodynamic%20stellarator | A quasi-isodynamic (QI) stellarator is a type of stellarator (a magnetic confinement fusion reactor) that satisfies the property of omnigeneity, avoids the potentially hazardous toroidal bootstrap current, and has minimal neoclassical transport in the collisionless regime.
Wendelstein 7-X, the largest stellarator in the world, was designed to be roughly quasi-isodynamic (QI).
In contrast to quasi-symmetric fields, exactly QI fields on flux surfaces cannot be expressed analytically. However, it has been shown that nearly-exact QI can be extremely well approximated through mathematical optimization, and that the resulting fields enjoy the aforementioned properties.
In a QI field, level curves of the magnetic field strength on a flux surface close poloidally (the short way around the torus), and not toroidally (the long way around), causing the stellarator to resemble a series of linked magnetic mirrors.
References
Fusion power
Nuclear reactors by type
Physics | Quasi-isodynamic stellarator | [
"Physics",
"Chemistry"
] | 205 | [
"Nuclear fusion",
"Fusion power",
"Plasma physics"
] |
75,464,679 | https://en.wikipedia.org/wiki/Dyakis%20dodecahedron | In geometry, the dyakis dodecahedron /ˈdʌɪəkɪsˌdəʊdɪkəˈhiːdrən/ or diploid is a variant of the deltoidal icositetrahedron with pyritohedral symmetry, transforming the kite faces into chiral quadrilaterals. The name diploid derives from the Greek word διπλάσιος (diplásios), meaning twofold since it has 2-fold symmetry along its 6 octahedral vertices. It has the same number of faces, edges, and vertices as the deltoidal icositetrahedron as they are topologically identical.
Construction
The dyakis dodecahedron can be constructed by enlarging 24 of the 48 faces of the disdyakis dodecahedron and is inscribed in the dyakis dodecahedron, thus it exists as a hemihedral form of it with indices {hkl}. It can be constructed into two non-regular pentagonal dodecahedra, the pyritohedron and the tetartoid. The transformation to the pyritohedron can be made by combining two adjacent trapezoids that share a long edge together into one hexagon face. The short edges of the hexagon can then be combined to finally get the pentagon. The transformation to the tetartoid can be made by enlarging 12 of the dyakis dodecahedron's 24 faces.
Properties
Since the quadrilaterals are chiral and non-regular, the dyakis dodecahedron is a non-uniform polyhedron, a type of polyhedron that is not vertex-transitive and does not have regular polygon faces. It is an isohedron, meaning that it is face transitive.
The dual polyhedron of a dyakis dodecahedron is the cantic snub octahedron.
In crystallography
The dyakis dodecahedron only exists in one crystal, pyrite. Pyrite has other forms other than the dyakis dodecahedron, including tetrahedra, octahedra, cubes and pyritohedra. Though the cube and octahedron are in the cubic crystal system, the dyakis dodecahedron and the pyritohedron are in the isometric crystal system and the tetrahedron is in the tetrahedral crystal system. Although the dyakis dodecahedron has 3-fold axes like the pyritohedron and cube, it doesn't have 4-fold axes, rather it has order-4 vertices, as when the dyakis dodecahedron is rotated 90 or 270° along an order-4 vertex, it is not the same as before, because the order-4 vertices act as 2-fold axes, as when they are rotated a full turn or 180°, the polyhedron looks the same as before.
References
Polyhedra
Crystallography
Pyrite group | Dyakis dodecahedron | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 599 | [
"Crystallography",
"Condensed matter physics",
"Materials science"
] |
75,465,176 | https://en.wikipedia.org/wiki/Ahlswede%E2%80%93Khachatrian%20theorem | In extremal set theory, the Ahlswede–Khachatrian theorem generalizes the Erdős–Ko–Rado theorem to -intersecting families. Given parameters , and , it describes the maximum size of a -intersecting family of subsets of of size , as well as the families achieving the maximum size.
Statement
Let be integer parameters. A -intersecting family is a collection of subsets of of size such that if then . Frankl
constructed the -intersecting families
The Ahlswede–Khachatrian theorem states that if is -intersecting then
Furthermore, equality is possible only if is equivalent to a Frankl family, meaning that it coincides with one after permuting the coordinates.
More explicitly, if
(where the upper bound is ignored when )
then , with equality if an only if is equivalent to ; and if
then , with equality if an only if is equivalent to or to .
History
Erdős, Ko and Rado showed that if then the maximum size of a -intersecting family is . Frankl proved that when , the same bound holds for all , which is tight due to the example . This was extended to all (using completely different techniques) by Wilson.
As for smaller , Erdős, Ko and Rado made the conjecture, which states that when , the maximum size of a -intersecting family is
which coincides with the size of the Frankl family . This conjecture is a special case of the Ahlswede–Khachatrian theorem.
Ahlswede and Khachatrian proved their theorem in two different ways: using generating sets and using its dual. Using similar techniques, they later proved the corresponding Hilton–Milner theorem, which determines the maximum size of a -intersecting family with the additional condition that no element is contained in all sets of the family.
Related results
Weighted version
Katona's intersection theorem determines the maximum size of an intersecting family of subsets of . When is odd, the unique optimal family consists of all sets of size at least (corresponding to the Majority function), and when is odd, the unique optimal families consist of all sets whose intersection with a fixed set of size is at least (Majority on coordinates).
Friedgut considered a measure-theoretic generalization of Katona's theorem, in which instead of maximizing the size of the intersecting family, we maximize its -measure, where is given by the formula
The measure corresponds to the process which chooses a random subset of by adding each element with probability independently.
Katona's intersection theorem is the case . Friedgut considered the case . The weighted analog of the Erdős–Ko–Rado theorem states that if is intersecting then for all , with equality if and only if consists of all sets containing a fixed point. Friedgut proved the analog of Wilson's result in this setting: if is -intersecting then for all , with equality if and only if consists of all sets containing fixed points. Friedgut's techniques are similar to Wilson's.
Dinur and Safra and Ahlswede and Khachatrian observed that the Ahlswede–Khachatrian theorem implies its own weighted version, for all . To state the weighted version, we first define the analogs of the Frankl families:
The weighted Ahlswede–Khachatrian theorem states that if is -intersecting then for all ,
with equality only if is equivalent to a Frankl family. Explicitly, is optimal in the range
The argument of Dinur and Safra proves this result for all , without the characterization of the optimal cases. The main idea is that if we take a random subset of of size , then the distribution of its intersection with tends to as .
Filmus proved weighted Ahlswede–Khachatrian theorem for all using the original arguments of Ahlswede and Khachatrian for , and using a different argument of Ahlswede and Khachatrian, originally used to provide an alternative proof of Katona's theorem, for . He also showed that the Frankl families are the unique optimal families for all .
Version for strings
Ahlswede and Khachatrian proved a version of the Ahlswede–Khachatrian theorem for strings over a finite alphabet. Given a finite alphabet , a collection of strings of length is -intersecting if any two strings in the collection agree in at least places. The analogs of the Frankl family in this setting are
where is an arbitrary word, and is the number of positions in which and agree.
The Ahlswede–Khachatrian theorem for strings states that if is -intersecting then
with equality if and only if is equivalent to a Frankl family.
The theorem is proved by a reduction to the weighted Ahlswede–Khachatrian theorem, with .
References
Notes
Works cited
Families of sets
Intersection
Theorems in discrete mathematics
Factorial and binomial topics
Extremal combinatorics | Ahlswede–Khachatrian theorem | [
"Mathematics"
] | 1,008 | [
"Discrete mathematics",
"Intersection",
"Extremal combinatorics",
"Factorial and binomial topics",
"Theorems in discrete mathematics",
"Combinatorics",
"Families of sets",
"Basic concepts in set theory",
"Mathematical problems",
"Operations on sets",
"Mathematical theorems"
] |
75,466,818 | https://en.wikipedia.org/wiki/HuCow | Human cow, or HuCow, is a BDSM subculture where people roleplay as dairy cows. Since the 2010s, it gained prominence through dedicated forums, fanart websites, and hentai repositories.
Description
HuCow participants broadly consider themselves as cows or farmers. The cow is usually submissive and objectified by the farmer. Scenes are often centered around the farmer milking the human cow's breasts. Human cows are often portrayed with large-sized breasts or pecs, and as being able to lactate. A popular trope in HuCow are settings which emulate the cattle industry, with names like The Dairy Department. Besides breast lactation, bondage is also prevalent in HuCow, where the human cow is bound by a harness to emulate livestock crushes. A dominant partner can also be cattle. In that case, they are instead referred to as a bull or HuBull and often incorporate breeding fetish components in HuCow scenes. In the gay community, both milking the nipples and milking the penis of its semen are popular fantasies. HuCow is also related to pet play, but unlike conventional forms such as kitten play, it formed a more defined subculture with a less generic name.
Accessories
Members of human cow communities also enjoy cosplay. Vendors on Amazon have started to offer products related to this community as the demand grew. Some accessories and costumes used by HuCows enthusiasts are:
Cow-printed onesies, body paint or bikinis
Cow-eared headbands
Detachable tails
Cattle ear tags
Breast pumping machines and penis pumping machines.
Prevalence
The modern concept of HuCow emerged in the early 2010s, but hentai porn has portrayed similar scenarios beforehand. HuCow participants span across all sexual orientations. According to Justin Lehmiller, a research fellow at the Kinsey Institute, the fetish is popular with gay and bisexual man communities because it incorporates transformation fantasies and BDSM, both of which are well-represented in queer male communities. As of 2018, the dedicated HuCow subreddit had more than 23,000 subscribers and a popular HuCow Tumblr had more than 10,000 followers. Some porn studios are dedicated to HuCow, like hucows.com.
In media
The 2018 Doja Cat single Mooo! is credited with rousing public interest in cow-branded apparel and cow-related fantasies.
See also
Breast fetish
Pup play
References
Sexual fetishism
Sexual roleplay
Sexology
Sexual attraction | HuCow | [
"Biology"
] | 517 | [
"Behavioural sciences",
"Behavior",
"Sexology"
] |
69,578,346 | https://en.wikipedia.org/wiki/Bismuth%20phosphide | Bismuth phosphide is a proposed inorganic compound with the chemical formula BiP. The structure of this material is unknown.
Synthesis
One route entails the reaction of sodium phosphide and bismuth trichloride in toluene (0 °C):
Another method uses tris(trimethylsilyl)phosphine in place of the sodium phosphide.
Physical properties
When heated in air, bismuth phosphide burns.
When heated in an atmosphere of carbon dioxide, a gradual volatilization of phosphorus is observed.
Chemical properties
This compound is oxidized when boiled in water.
All strong acids dissolve it.
References
Phosphides
Bismuth compounds
Semiconductors | Bismuth phosphide | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 149 | [
"Electrical resistance and conductance",
"Physical quantities",
"Semiconductors",
"Materials",
"Electronic engineering",
"Condensed matter physics",
"Solid state engineering",
"Matter"
] |
69,579,267 | https://en.wikipedia.org/wiki/Holmium%20phosphide | Holmium phosphide is a binary inorganic compound of holmium and phosphorus with the chemical formula HoP. The compound forms dark crystals, is stable in air, and does not dissolve in water.
Synthesis
Heating powdered holmium and red phosphorus in an inert atmosphere or vacuum:
Properties
HoP belongs to the large class of NaCl-structured rare earth monopnictides.
Ferromagnetic at low temperatures.
HoP actively reacts with nitric acid.
Uses
The compound is a semiconductor used in high power, high frequency applications and in laser diodes.
References
Phosphides
Holmium compounds
Semiconductors
Rock salt crystal structure | Holmium phosphide | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 130 | [
"Electrical resistance and conductance",
"Physical quantities",
"Semiconductors",
"Materials",
"Electronic engineering",
"Condensed matter physics",
"Solid state engineering",
"Matter"
] |
69,579,497 | https://en.wikipedia.org/wiki/Ivermectin%20during%20the%20COVID-19%20pandemic | Ivermectin is an antiparasitic drug that is well established for use in animals and people. The World Health Organization (WHO), the European Medicines Agency (EMA), the United States Food and Drug Administration (FDA), and the Infectious Diseases Society of America (IDSA) all advise against using ivermectin in an attempt to treat or prevent COVID-19.
Early in the COVID-19 pandemic, laboratory research suggested ivermectin might have a role in preventing or treating COVID-19. Online misinformation campaigns and advocacy boosted the drug's profile among the public. While scientists and physicians largely remained skeptical, some nations adopted ivermectin as part of their pandemic-control efforts. Some people, desperate to use ivermectin without a prescription, took veterinary preparations, which led to shortages of supplies of ivermectin for animal treatment. The FDA responded to this situation by saying "You are not a horse" in a tweet to draw attention to the issue, for which they were later sued by three ivermectin-prescribing doctors.
Subsequent research failed to confirm the utility of ivermectin for COVID-19, and in 2021 it emerged that many of the studies demonstrating benefit were faulty, misleading, or fraudulent. Nevertheless, misinformation about ivermectin continued to be propagated on social media and the drug remained a cause célèbre for anti-vaccinationists and conspiracy theorists.
Research
Some in vitro drug screening studies early in the pandemic showed that ivermectin has antiviral effects against several distinct positive-sense single-strand RNA viruses, including SARS-CoV-2. Subsequent studies found that ivermectin could inhibit replication of SARS-CoV-2 in monkey kidney cell culture with an IC50 of 2.2–2.8 μM.
However, doses much higher than the maximum approved or safely achievable for use in humans would be required for an antiviral effect while treating COVID-19. Aside from practical difficulties, such high doses are not covered by current human-use approvals of the drug and may be toxic, as the antiviral mechanism of action is believed to be via the suppression of a host cellular process, specifically the inhibition of nuclear transport by importin α/β1. Several other drugs which inhibit importin α/β1 at therapeutic doses have failed clinical trials due to systemic toxicity and a narrow therapeutic window.
To resolve uncertainties from previous small or poor-quality studies, , large scale trials were underway in the United States and the United Kingdom. A large randomised controlled trial ACTIV-6, published in October 2022, found ivermectin was not effective as a COVID-19 treatment.
Research limitations, ethics and fraud
Many studies on ivermectin for COVID‑19 have serious methodological limitations, resulting in very low evidence certainty. Several publications that supported the efficacy of ivermectin for COVID‑19 have been retracted due to errors, unverifiable data, and ethical concerns.
Several high-profile publications purporting to demonstrate reduced mortality in COVID-19 patients were later retracted due to suspected data falsification. This only added to confusion among the media and lay public, as these publications had been widely cited by ivermectin supporters and included in meta-analyses.
In January 2022, 22 inmates at the Washington County Detention Center in Arkansas filed a lawsuit over hundreds of ivermectin pills given to them as "vitamins" in 2020.
In February 2022, the American Journal of Therapeutics issued expressions of concern against two positive systematic reviews of ivermectin for COVID-19 which it had published in 2021, because of suspicions about the underlying data that would undermine these papers' findings of benefit.
In Mexico City the government distributed ivermectin widely as a COVID-19 treatment and published the observed results on the SocArXiv archive as a research paper. The paper was subsequently withdrawn by the archive citing concerns that it was unethical, as it effectively was an experiment carried out on people without gaining informed consent. Philip N. Cohen of the SocArXiv steering committee said "the article is of very poor quality or deliberately false and misleading" and that its removal was justified to prevent public harm.
Clinical guidance
In February 2021, Merck, the developer of the drug, issued a statement saying that there is no good evidence ivermectin is effective against COVID‑19 and that attempting such use may be unsafe.
After reviewing the evidence on ivermectin, the European Medicines Agency (EMA) advised against its use for prevention or treatment of COVID‑19 and that "the available data do not support its use for COVID‑19 outside well-designed clinical trials." Consequently, ivermectin is not authorized for use to treat COVID‑19 within the European Union.
Ivermectin is not approved by the U.S. Food and Drug Administration (FDA) for use in treating any viral illness, and the U.S. National Institutes of Health COVID‑19 Treatment Guidelines state that there is insufficient evidence for ivermectin to allow for a recommendation for or against its use.
In the United Kingdom, the national COVID‑19 Therapeutics Advisory Panel determined that the evidence base and plausibility of ivermectin as a COVID‑19 treatment were insufficient to pursue further investigations.
In November 2023, the WHO updated its treatment guidelines to recommend strongly against the use of ivermectin as a COVID-19 treatment, due to a lack of research evidence or biological plausibility.
The Brazilian Health Regulatory Agency, Brazilian Society of Infectious Diseases, and Brazilian Thoracic Society issued position statements advising against the use of ivermectin for prevention or treatment of early-stage COVID‑19.
COVID-19 and strongyloidiasis
There is one very specific circumstance in which ivermectin may be useful in the management of COVID-19. People infected with the Strongyloides stercoralis parasite are at risk for strongyloides hyperinfection syndrome (SHS) — a condition with a mortality rate as high as 90% — if given corticosteroids to treat COVID-19. Strongyloidiasis affects as many as 370 million people worldwide, and it is usually subclinical or even asymptomatic. However, it can become fatal in the setting of SHS, which can be triggered by the immunosuppression that results from the administration of corticosteroids. In fact, multiple cases of SHS have been reported after the use of corticosteroids in the management of COVID-19 pneumonia. For this reason, the World Health Organization (WHO), the European Centre for Disease Prevention and Control (ECDC), the Public Health Agency of Canada (PHAC) and the United States Centers for Disease Control and Prevention (CDC) all recommend presumptive treatment for strongyloidiasis with ivermectin in people at high or moderate risk of SHS before or in conjunction with corticosteroids in the management of COVID-19. People who were born, resided, or had long-term travel in Southeast Asia, Oceania, sub-Saharan Africa, South America, or the Caribbean are considered to be at high risk for SHS, while people from Central America, Eastern Europe, the Mediterranean, Mexico, Middle East, North Africa, and the Indian subcontinent are considered to be at moderate risk. In such cases, ivermectin is a treatment for strongyloidiasis, not for COVID-19.
Regulatory status and off-label use
Misinformation, lower degrees of trust, and a sense of despair over increasing case and death counts have led to an increase in ivermectin's use in Central and Eastern Europe, Latin America, and South Africa. A black market has also developed in many of these countries where official approval has not been granted.
The viral social media misinformation about ivermectin has gained particular attention in South Africa where an anti-vaccination group called "South Africa Has A Right To Ivermectin" has been lobbying for the drug to be made available for prescription. Another group, the "Ivermectin Interest Group" launched a court case against the South African Health Products Regulatory Authority (SAHPRA), and as a result a compassionate use exemption was granted. SAHPRA stated in April 2021 that "At present, there are no approved treatments for COVID-19 infections." In September 2021, SAHPRA repeated warnings against fake news and misinformation and took up the FDA's stance about ivermectin. Due to lacking evidence of efficacy and growing body of retracted pro-ivermectin papers, SAHPRA revoked the compassionate use program in May 2022.
Despite the absence of high-quality evidence to suggest any efficacy and advice to the contrary, some governments have allowed its off-label use for the prevention and treatment of COVID‑19. Countries that have granted such official approval for ivermectin include the Czech Republic, Slovakia, Mexico, Peru (later rescinded), India (later rescinded), and the Philippines. Cities that have launched campaigns of massive distribution of ivermectin include Cali, Colombia; and Itajai, Brazil.
In Arkansas in 2021, a prison doctor prescribed ivermectin for inmates without their consent. A legal action brought on the inmates' behalf by the American Civil Liberties Union (ACLU) was settled with the prison authorities paying compensation. The ACLU said the outcome was "victory for civil rights and medical ethics".
Ivermectin is not approved by the U.S. Food and Drug Administration (FDA) for use in treating any viral illness and is not authorized for use to treat COVID-19 within the European Union. After reviewing the evidence on ivermectin, the EMA said that "the available data do not support its use for COVID-19 outside well-designed clinical trials". The World Health Organization also said that ivermectin should not be used to treat COVID-19 except in a clinical trial. The Brazilian Health Regulatory Agency, Brazilian Society of Infectious Diseases, and Brazilian Thoracic Society issued position statements advising against the use of ivermectin for prevention or treatment of early-stage COVID-19.
Several Latin American government health organizations recommended ivermectin as a COVID-19 treatment based, in part, on preprints and anecdotal evidence; these recommendations were later denounced by the Pan American Health Organization.
In the United States, an analysis of prescribing data suggested the influence of political affiliation, as Republican-voting areas saw a pronounced surge in ivermectin (and hydroxychloroquine) prescription in 2020.
Human use of veterinary products
As people began using veterinary preparations of ivermectin for personal use stocks began to decline, requiring vendors to ration their sales and raise prices. In the United States supplies of horse dewormer paste began to run low as people used it for themselves; some vendors required their customers to show a picture of themselves and their horses together, to provide assurance they were purchasing the paste for animal use.
In August 2021 the CDC issued a health alert prompted by a sharp rise in calls to poison control centres about ivermectin poisoning. The CDC described two cases requiring hospitalization; in one, a person had drunk an injectable ivermectin product intended for use in cattle.
In August 2021, the FDA tweeted "You are not a horse. You are not a cow. Seriously, y'all. Stop it". Following a legal challenge from ivermectin-prescribing doctors, in August 2023 a US court found the FDA had exceeded its authority by posting the tweet, which they said amounted to medical advice, and that doctors could prescribe whatever they wanted. Remarks made during the legal proceedings were misrepresented on social media to claim that the FDA had somehow reversed its position on ivermectin and COVID-19, which in reality remained unchanged. In March 2024 the FDA settled outstanding litigation and removed all social media posts that could be construed as giving medical advice and thus exceeding its statutory authority, while re-iterating that its position remained unchanged and that "currently available clinical trial data do not demonstrate that ivermectin is effective against COVID-19".
Intellectual property and economics
As the patent on ivermectin has expired, generic drug manufacturers have been able to enjoy significantly increased revenue prompted by the spike in demand. One Brazilian company, Vitamedic Industria Farmaceutica, saw its annual revenue from ivermectin sales increase to $85 million in 2020, a more than fivefold increase.
In Australia in 2020 Thomas Borody, a professor and gastroenterologist, announced that he had discovered a "cure" for COVID-19: a combination of ivermectin, doxycycline and zinc. In a media interview Borody stated "The biggest thing about this is no one will make money from this". It later emerged that Topelia Australia, Borody's company, had filed a patent for the drug combination. Borody was accused of not adequately disclosing his conflict of interest.
In October 2021 a large network of companies selling hydroxychloroquine and ivermectin was disclosed in the US, targeting primarily right-wing and vaccine-hesitant groups through social media and conspiracy videos by anti-vaccine activists such as Simone Gold. The network had 72,000 customers who collectively paid $15 million for consultations and medications.
Misinformation and advocacy
Ivermectin became a cause célèbre for right-wing figures promoting it as a supposed COVID treatment. Misinformation about ivermectin's efficacy spread widely on social media, fueled by publications that have since been retracted, misleading "meta-analysis" websites with substandard methods, and conspiracy theories about efforts by governments and scientists to "suppress the evidence."
Social media advocacy
Ivermectin has been championed by a number of social media influencers.
American podcaster and author Bret Weinstein took ivermectin during a livestream video and said both he and his wife Heather Heying had not been vaccinated because of their fears concerning COVID-19 vaccines. In response, YouTube demonetized the channel.
In the United Kingdom, retired nurse educator and YouTuber John Campbell has posted videos carrying false claims about the use of ivermectin in Japan as a possible cause of a "miracle" decline in cases. In reality, there is no evidence of ivermectin use in Japan and it is not approved as a COVID-19 treatment. In February 2022, reports also appeared falsely claiming that the Japanese company Kowa had been able to evidence the efficacy of ivermectin in a phase III trial.
Misleading meta-analysis websites
During the pandemic, several misleading websites appeared purporting to show meta-analyses of clinical evidence in favor of ivermectin's use in treating COVID-19. The sites in question had anonymous owners, multiple domains which redirected to the same content, and used many colourful, but misleading, graphics to communicate their point. The web servers used for these sites are the same as those previously used to spread misinformation about hydroxychloroquine.
While these sites gained traction among many non-scientists on social media, they also violated many of the basic norms of meta-analysis methodology. Notably, many of these sites included studies with widely different dosages of the treatment, an open-label design (in which experimenters and participants both know who is in the control group), poor-quality control groups (such as another untested treatment which may worsen outcomes), or no control group at all. Another issue is the inclusion of multiple ad-hoc unpublished trials which did not undergo peer-review, and which had different incompatible outcome measures. Such methodological problems are known to distort the findings of meta-analyses and cause spurious or false findings. The misinformation communicated by these sites created confusion among the public and policymakers.
Fake endorsements
On Twitter, a tweet spread with a photograph of William C. Campbell, the co-inventor of ivermectin, alongside a fabricated quotation saying that he endorsed ivermectin as a COVID treatment. Campbell reacted by saying "I utterly despise and deny the remarks attributed to me on social media" adding that his field of expertise was not virology so he would never comment in such a way.
In February 2022 a report was broadcast by Australia's Nine Network about Queen Elizabeth II having COVID-19. The segment featured Mukesh Haikerwal and included an intercut image of a box of ivermectin tablets, leading antivaxxers to spread the idea via social media that ivermectin was being specially used, as a "treatment fit for a queen". Haikerwal stated that he rejected ivermectin as a COVID-19 treatment, and the network issued an apology to him, saying the ivermectin image has been included "as a result of human error".
Scientists targeted
In July 2021 Andrew Hill, a senior research fellow at Liverpool University, published a meta-analysis of ivermectin use for COVID which suggested it may be beneficial. However, as research fraud subsequently emerged in some studies included in the meta-analysis, Hill revised his analysis to discount the suspect evidence, and found the apparent success of ivermectin evaporated as a result. Writing for The Guardian, Hill recounted how the revision led to him being attacked on social media as being supposedly in the pay of Bill Gates, and how he was sent photos of coffins and hanged nazis.
Epidemiologist Gideon Meyerowitz-Katz has identified ivermectin as being one of the most politicized topics in the pandemic, alongside vaccination. Meyerowitz-Katz has used social media to publicize flaws in ivermectin research and as a result, he says, has received more death threats than for any other topic he has engaged with.
Front Line COVID-19 Critical Care Alliance
In December 2020, the chair of the US Senate Homeland Security Committee, Ron Johnson, used a Senate hearing to promote fringe theories about, and unproven treatments for, COVID-19, including ivermectin. Among the witnesses was Pierre Kory, a pulmonary and critical care doctor, who erroneously described ivermectin as "miraculous" and a "wonder drug" to be used against COVID-19. Video footage of his statements went viral on social media, receiving over one million views as of 11 December 2020.
In the United States, the use of ivermectin for COVID-19 is championed by an organization led by Kory called Front Line COVID-19 Critical Care Alliance (FLCCC), which promotes "the global movement to move #Ivermectin into the mainstream". The effort went viral on social media, where it was adopted by COVID deniers, anti-vaccination proponents, and conspiracy theorists. A review article by FLCCC members on the efficacy of ivermectin, which had been provisionally accepted by a Frontiers in Pharmacology, was subsequently rejected on account of what the publisher called "a series of strong, unsupported claims based on studies with insufficient statistical significance" meaning that the article did "not offer an objective [or] balanced scientific contribution to the evaluation of ivermectin as a potential treatment for COVID-19". David Gorski wrote that the narrative of ivermectin as a "miracle cure" for COVID-19 is a "metastasized" version of a similar conspiracy theory around the drug hydroxychloroquine, in which unspecified powers are thought to be suppressing news of the drug's effectiveness for their own profit.
Pfizer's drug development
Conspiracy theorists on the internet have claimed that Pfizer's anti-COVID-19 drug paxlovid is merely "repackaged ivermectin". Their claims are based on a narrative that Pfizer is suppressing the true benefits of ivermectin and rely on superficial correspondences between the drugs and a misunderstanding of their respective pharmokinetics. Paxlovid is a combination drug of two small-molecule antiviral compounds (nirmatrelvir and ritonavir) which have no connection to ivermectin.
Aftermath
The widespread misconduct found in ivermectin/COVID-19 research has prompted introspection within the scientific community.
Australian epidemiologist Gideon Meyerowitz-Katz wrote, "There are no two ways about it: Science is flawed". Meyerowitz-Katz estimates that as of December 2021, credence in flawed research had led to ivermectin being perhaps the most used medication worldwide during the pandemic and that the scale of the problem suggested a radical rethink was needed of how medical research was assessed.
See also
Big Pharma conspiracy theories
COVID-19 drug repurposing research
COVID-19 misinformation
Chloroquine and hydroxychloroquine during the COVID-19 pandemic
References
Communication of falsehoods
Conspiracy theories
COVID-19 misinformation
Fake news
Impact of the COVID-19 pandemic on journalism
Health-related conspiracy theories
Misinformation
Pseudoscience
Vaccine hesitancy
fr:Développement et recherche de médicaments contre la Covid-19#Ivermectine | Ivermectin during the COVID-19 pandemic | [
"Technology"
] | 4,635 | [
"Health-related conspiracy theories",
"Science and technology-related conspiracy theories"
] |
69,583,525 | https://en.wikipedia.org/wiki/Niesslia%20peltigerae | Niesslia peltigerae is a species of lichenicolous fungus in the family Niessliaceae. It was described as a new species in 2020 by lichenologist Sergio Pérez-Ortega. The type specimen was collected in the Hoonah-Angoon Census Area of Glacier Bay National Park, in muskeg and forest. The fungus was growing parasitically on the lichen Peltigera kristinssonii, which itself was growing on mountain hemlock (Tsuga mertensiana). The specific epithet peltigerae alludes to the genus of its host. Infection by the fungus bleaches the thallus of the host lichen.
References
Niessliaceae
Fungi described in 2020
Fungi of the United States
Lichenicolous fungi
Fungi without expected TNC conservation status
Fungus species | Niesslia peltigerae | [
"Biology"
] | 166 | [
"Fungi",
"Fungus species"
] |
69,585,294 | https://en.wikipedia.org/wiki/Amaurodon%20caeruleocaseus | Amaurodon caeruleocaseus is a species of fungus in the family Thelephoraceae. It was described by Sten Svantesson and Tom W. May in 2021. It is unique within its genus in that its basidiome is stipitate. The specific epithet is Latin (a compound of 'blue' and 'cheese'), named for the basidiome's resemblance to blue cheese. The type locality is Denmark, Western Australia.
See also
Fungi of Australia
References
External links
Thelephorales
Fungi described in 2021
Fungi of Australia
Taxa named by Tom May (mycologist)
Fungus species | Amaurodon caeruleocaseus | [
"Biology"
] | 131 | [
"Fungi",
"Fungus species"
] |
69,585,537 | https://en.wikipedia.org/wiki/FK962 | FK962 is a compound which acts as an enhancer of somatostatin release. It stimulates nerve growth and neurite elongation, and has been researched in animal models for potential applications in the treatment of conditions such as Alzheimer's disease and retinal neuropathy.
See also
Octreotide
Pasireotide
Sunifiram (structural similarity)
References
Pharmacology
Acetamides
Benzamides
Piperidines
4-Fluorophenyl compounds | FK962 | [
"Chemistry"
] | 102 | [
"Pharmacology",
"Medicinal chemistry"
] |
69,585,566 | https://en.wikipedia.org/wiki/Cristina%20Sernadas | Maria Cristina De Sales Viana Serôdio Sernadas (born 1951) is a Portuguese mathematical logician whose research topics have included object-oriented specification languages and logics for information systems, and the use of category theory in the combination ("fibring") of multiple types of logic. She is Professor for Logic and Computation in the Department of Mathematics of the Technical University of Lisbon.
Education and career
Sernadas studied mathematics at the University of Lisbon, graduating in 1973, and earned a Ph.D. in mathematics in 1980 from the University of London. Her doctoral dissertation, Multivariate Branching Processes, concerned branching processes in probability theory, and was supervised by statistician D. J. Bartholomew.
In 1988 she completed a habilitation (agregação) at the Technical University of Lisbon, and became a full professor there in 1993.
Books
Sernadas's books include:
Introdução à Teoria da Computação (Introduction to the Theory of Computing, Editorial Presença, 1993)
Introdução à Programação em Mathematica (Introduction to Programming in Mathematica, with J. Carmo, A. Sernadas, F. M. Dionísio, and C. Caleiro, IST Press, 1999; 2nd ed., 2004; 3rd ed., 2014)
Foundations of Logic and Theory of Computation (with A. Sernadas, College Publications, 2008; 2nd ed., 2012)
Analysis and Synthesis of Logics: How To Cut And Paste Reasoning Systems (with W. A. Carnielli, M. E. Coniglio, D. Gabbay, and P. Gouveia, Springer, 2008)
A Mathematical Primer on Computability (with A. Sernadas, J. Rasga and J. Ramos, College Publications, 2018)
A Mathematical Primer on Linear Optimization (with D. Gomes, A. Sernadas, J. Rasga and P. Mateus, College Publications, 2019)
Decidability of Logical Theories and Their Combination (with J. Rasga, Springer, 2020)
References
External links
1951 births
Living people
20th-century Portuguese mathematicians
Mathematical logicians
Women logicians
Women mathematicians
University of Lisbon alumni
Alumni of the University of London
Academic staff of the Technical University of Lisbon
21st-century Portuguese mathematicians | Cristina Sernadas | [
"Mathematics"
] | 478 | [
"Mathematical logic",
"Mathematical logicians"
] |
69,586,295 | https://en.wikipedia.org/wiki/Process%20tracing%20in%20psychology | Process tracing methods in psychology are defined as observations which are made before the participant has come to a decision. These observations are used to present us with information regarding the psychological processes occurring within a participant, while they are weighing their choices. More specifically, process tracing methods examine participant's information acquisition process, how much information or content they've acquired, for how long this process occurred etc. Process tracing methods can also test the subtleties of decision making, since how the information is presented can change decisions, which can shed more light in what influences decisions and how people process information. Most of these methods are considered to be particularly unobtrusive, since the processes that they study are generally natural (i.e. eye gazing), and do not interfere with the decision process. Process-tracing in psychology can consist of various methods, namely observational, experimental, physiological, or neuroscientific.
There are two criteria that process tracing methods which study psychological processes should fit. Primarily, there has to be some measurable cognitive changes during the process, and secondarily, the data being collected must test the hypothesis made.
Methods
What differentiates process tracing methods from other methods that study decision making, is that they usually aim to study the processes which are occurring before or during the time a decision is made. For example, the measurement of reaction time cannot be considered a process-tracing method, since although they study the amount of time it takes for a participant to make a decision, they do not shed light on the cognitive processes underlying it.
There are many different ways underlying cognitive decision making can be studied, but there are three main methods in which process-tracing techniques are divided. Movement-based measures provide data on information research patterns. Subject reports measures observe decision strategies usually through having the participants verbalize their thought processes. Peripheral psychophysiological measures quantify arousal and cognitive effort.
Method 1 - Movement-based methods
Movement-based methods are used for tracing information acquisition. Some specific ones are eye tracking (Eyegaze), mouse tracing (Mouselab), or other active information search methods. These methods avoid participant self report and various other process interruptions. Furthermore, they are less expensive, and have a wider outreach than other methods, which makes them highly attractive to study various cognitive processes.
The methods, however, can have differences between each other. For example, it has been reported that computerized tools such as mouse tracing take longer to assess information than do methods such as eye gaze. There is further research to be done regarding the complete consequences of the difference between these methods.
Method 2 - Subject reports
Methods for tracing information integration are used after the participant has presumably formed a perception of the information presented to her. These methods aim to study how the information is integrated after it has been introduced, and how that integration leads to a choice. A popular model to study information integration is verbalized thoughts. Unlike movement-based methods, verbal methods are more direct, they aim to measure the internal process and not the behavior of the participant.
Method 3 - Peripheral psychophysiological processes
Psychophysiological processes focus primarily on studying how different brain regions are activated during decision making. The techniques of this method include electrodermal activity, pupil dilation, or fMRI. Such methods are now being used to shed light in organizational neuroscience, specifically decision making
Advantages
Before process-tracing, the study of cognitive processes relied on participants reporting experienced difficulties during or after the experiment, which would potentially result in the participant justifying their process, participant anticipating the questions and therefore providing a biased description, and participant having difficulties recalling process and therefore misreporting it. As mentioned above, current process-tracing methods allow us to infer cognitive processes without interrupting natural cognitive procedures. Methods such as measuring heart rate have shed light in choices related to risk aversion. Methods such as fMRI and EEG shed light on the neural circuits involved in decision making and how they interact with each other. Methods such as TMS allow research to observe behavioral change by intervening in neural circuits. Additionally, computational neuroscience is developing in a way that allows us to replicate these mechanisms and further analyze them through data.
Limitations
There are a few limitations that come with process-tracing methods, primarily because some methods are more intrusive then others, and with intrusive methods one should be cautious with the results they produce. Distortion risks could be presented when using methods such as cameras or microphones for observation, or when presenting information to participants in different ways. We can also not discount the potential risks of these experiments happening in unnatural environments, especially when involving such methods as fMRI scans
As mentioned above, different process tracing methods require different levels of effort in order to analyze data. It is still a question whether the usage of different process tracing methods changes the decision-making process, and therefore provides us with different results. It is also a question how each process tracing method could potentially change the results, and how can we control for this interruption in validity?. For example, Russo (1977) changed supermarket shopper's choices by pushing them towards purchasing products with lower unit prices.
References
Behavioral concepts
Experimental psychology | Process tracing in psychology | [
"Biology"
] | 1,044 | [
"Behavior",
"Behavioral concepts",
"Behaviorism"
] |
69,591,470 | https://en.wikipedia.org/wiki/Tengiz%20Beridze | Tengiz Beridze (Georgian: თენგიზ გიორგის ძე ბერიძე; 26 October 1939 – 3 December 2024) was a Georgian biochemist.
Life and career
In 1967 Beridze discovered satellite DNA in plants. Through his research from 1972 to 1975, it was found that closely related species of one genus differ in satellite DNA content. In 1986 he published the monograph Satellite DNA in Springer Edition. In 2013 this monograph was edited as an eBOOK.
In 2011-17 he established a complete nucleotide sequence of four Georgian grape varieties, nuclear, chloroplast and mitochondria.
In 2015–21 he established a complete chloroplast DNA sequence of Georgian wheat species.
In 1967, he defended his Candidate's Dissertation. In 1980, he defended his doctoral dissertation in the Bakh Institute of Biochemistry, Moscow. He was elected a corresponding member of the Academy of Sciences of Georgia in 1987 and a full member in 1993.
Beridze held various positions in Soviet and Georgian institutions since 1960s.
Beridze died on 3 December 2024, at the age of 85.
Positions
1968–2008 – Institute of Biochemistry and Biotechnology, Georgian Academy of Sciences
1968–1999 – Professor at Tbilisi State University, Georgia
2008–2010 – Professor at Ilia State University, Tbilisi, Georgia
2010–2011 – Professor at Free University of Tbilisi, Georgia
2012–2021 – Director of Institute of Molecular Genetics, Agricultural University of Georgia
2012–20?? – Professor at Agricultural University of Georgia, Tbilisi, Georgia
Awards
Beridze was awarded the Order of Honour of Georgia in 1999. He was awarded the Serge Durmishidze prize in Biochemistry in 2009.
Selected publications
Beridze TG, Odintsova MS, Sissakian NM (1967) Distribution of bean leaf DNA components in the cell organelle fractions. Molek.Biol.USSR. 1,142-153
Beridze TG (1972) DNA nuclear satellites of the genus Phaseolus. Biochim. Biophys. Acta 262,393-396
Beridze TG (1975) DNA nuclear satellites of the genus Brassica: variation between species. Biochim.Biophys.Acta. 395,274-279
Beridze T. Satellite DNA, 1986, Springer-Verlag, Berlin, Heidelberg, New York, Tokio
Beridze T, Pipia I, Beck J., Hsu S.-CT, Gamkrelidze M, Gogniashvili M, Tabidze V, This R,Bacilieri P, Gotsiridze V, Glonti M, Schaal B (2011). Plastid DNA sequence diversity in a worldwide set of grapevine cultivars (Vitis vinifera L. subsp. vinifera). Bulletin of the Georgian National Academy of Sciences. 5, 2011, 98–103.
Pipia I, Gogniashvili M, Tabidze V, Beridze T, Gamkrelidze M, Gotsiridze V, Melyan G, Musayev M, Salimov V, Beck J, Schaal B (2012) Plastid DNA sequence diversity in wild grapevine samples (Vitis vinifera subsp. sylvestris) from the Caucasus region. Vitis 51 (3), 119–124
Tabidze V, Baramidze G, Pipia I, Gogniashvili M, Ujmajuridze L, Beridze T, Hernandez AG, Schaal B (2014) The Complete Chloroplast DNA Sequence of Eleven Grape Cultivars. Simultaneous Resequencing Methodology. Journal International des Sciences de la Vigne et du Vin J Int Sci Vigne Vin. 48, 99-109
Tabidze V, Pipia I, Gogniashvili M, Kunelauri N, Ujmajuridze L, Pirtskhalava M, Vishnepolsky B, Hernandez AG, Fields CJ, BeridzeT (2017) Whole genome comparative analysis of four Georgian grape cultivars. Molecular Genetics and Genomics. 292, 1377-1389
Gogniashvili M., Naskidashvili P., Bedoshvili D., Kotorashvili A., Kotaria N., Beridze T. (2015) Complete chloroplast DNA sequences of Zanduri wheat (Triticum spp.) Genet Resour Crop Evol
Gogniashvili M, Jinjikhadze T, Maisaia M, Akhalkatsi M, Kotorashvili A, Kotaria N, Beridze T, Dudnikov AJ (2016) Complete chloroplast genomes of Aegilops tauschii Coss. and Ae.cylindrica Host sheds light on plasmon D evolution. Current Genetics.
Gogniashvili M, Maisaia I, Kotorashvili A, Kotaria N, Beridze T (2018) Complete chloroplast DNA sequences of Georgian indigenous polyploid wheats (Triticum spp.) and B plasmon evolution. Genet Resour Crop Evol 65:1995–2002
References
1939 births
2024 deaths
Georgian Soviet Socialist Republic people
Scientists from Tbilisi
Biochemists
Academic staff of Tbilisi State University
Academic staff of Ilia State University
Free University of Tbilisi people
Recipients of the Order of Honor (Georgia) | Tengiz Beridze | [
"Chemistry",
"Biology"
] | 1,133 | [
"Biochemistry",
"Biochemists"
] |
69,591,893 | https://en.wikipedia.org/wiki/GLPG-0492 | GLPG-0492 (DT-200) is a drug which acts as a selective androgen receptor modulator (SARM). It has been investigated for the treatment of cachexia and muscular dystrophy.
See also
ACP-105
Enobosarm
JNJ-28330835
Ligandrol
References
Selective androgen receptor modulators
Trifluoromethyl compounds
Hydantoins
Nitriles
Hydroxymethyl compounds
Benzonitriles | GLPG-0492 | [
"Chemistry"
] | 100 | [
"Nitriles",
"Functional groups"
] |
69,592,341 | https://en.wikipedia.org/wiki/Trimethylolpropane%20ethoxylate | Trimethylolpropane ethoxylate (TPEG) is a trifunctional polyether compound derived from trimethylolpropane.
Production
TPEG is produced by ethoxylation of trimethylolpropane.
Applications
TPEG is used in the production of polyurethane foams, elastomers, and sealants.
References
Polyethers
Polymers | Trimethylolpropane ethoxylate | [
"Chemistry",
"Materials_science"
] | 89 | [
"Polymers",
"Polymer chemistry"
] |
69,593,647 | https://en.wikipedia.org/wiki/LUCAS%20device | The Lund University Cardiopulmonary Assist System (LUCAS) device provides mechanical chest compressions to patients in cardiac arrest. It is mostly used in emergency medicine as an alternative to manual CPR because it provides consistent compressions at a fixed rate through difficult transport conditions and eliminates the physical strain on the person performing CPR. The first generation of the LUCAS device (released in 2003) was pneumatic, while the second and third generations are battery-operated.
Development
After watching paramedics struggling to perform manual CPR on a patient while in the back of a speeding ambulance, Norwegian inventor Willy Vistung came up with the idea for a pneumatic system that could provide automatic, mechanical chest compressions. Cardiothoracic surgeon Stig Steen supported Vistung's idea, and after Vistung's death, Swedish entrepreneur Lars Sunnanväder and Steen developed the final prototype. Steen and his research team did studies at Lund University Hospital, and in 2000, Steen began using it clinically.
In 2003, Swedish ambulances began using the first generation of the LUCAS device, which was driven pneumatically. In 2009, the second generation LUCAS, which had both pneumatic and battery-driven configurations, was released worldwide. In 2016, the most recent generation, LUCAS 3, became commercially available.
Use
The LUCAS can be used both in and out of the hospital setting. The 2015 European Resuscitation Council Guidelines for Resuscitation does not recommend using mechanical chest compression on a routine basis, but are good alternative for situations where it may be difficult or to maintain continuous high-quality compressions, or when it may be too strenuous on the medic to do so. However, more ambulance services have integrated it into their ACLS protocols, usually recommending the application of the LUCAS after roughly 15 minutes of CPR by First Responders without success.
To place the device on the patient, the medic first places the back plate under the patient. This eliminates the "mattress effect" and ensures the device stays in place. Next, the medic attaches the upper part of the device by locking the support legs onto the sides of the back board. Once everything is lined up correctly, the medic can place the suction cup over the patient's chest and turn it on. Finally, the medic will buckle the stabilization strap around the back of the patient's neck and secure their wrists to the device to make transport easier.
The LUCAS can be set to different rates and compression modes depending on what the patient's situation requires.
Effectiveness
When in transport via ground ambulance, even experienced resuscitators can struggle to maintain effective compressions with minimal interruptions. The LUCAS device delivers high-quality compressions at a continuous rate, while up to a third of manual compressions can be incorrect. In 2013, a 68-year-old male made a complete recovery, including no intellectual or neurological deficits, after an out-of-hospital cardiac arrest after 59 minutes of mechanical compressions on a LUCAS device.
Patients who experience an out-of-hospital cardiac arrest do not have a significantly higher chance of return of spontaneous circulation (ROSC) with a LUCAS device (33.3%) versus manual CPR (33.0%). There is not a significant difference in those who survive to hospital admission, either: 22.7% survival rate for the LUCAS group versus 24.3% for the manual group
References
Medical devices
Emergency medical equipment
Swedish inventions | LUCAS device | [
"Biology"
] | 718 | [
"Medical devices",
"Medical technology"
] |
69,593,652 | https://en.wikipedia.org/wiki/Bartolomeo%20Beretta | Bartolomeo Beretta (c. 1490 – c. 1565), known as maestro di canne (master gun-barrel maker), was an Italian artisan from Lombardy who, by 1526, had established the arms manufacturing enterprise Beretta.
Beretta worked at Gardone in Val Trompia, then in the Republic of Venice, where he was the village ironmaster. He became known for his attention to detail and was a prolific maker of gun barrels. In 1526, the Venetian Arsenal paid him 296 ducats for 185 arquebus barrels.
The iron foundry and arms business was continued and developed by Beretta's son Jacopo and grandson Giovannino, and the Beretta family remains in control of the business in the 21st century. Encyclopedia Britannica calls Beretta “one of the world’s oldest industrial enterprises”.
References
16th-century Venetian businesspeople
Italian artisans
Firearm designers
Ironmasters
1490s births
1560s deaths
Beretta
Company founders | Bartolomeo Beretta | [
"Chemistry"
] | 209 | [
"Metallurgists",
"Ironmasters"
] |
77,087,779 | https://en.wikipedia.org/wiki/PKS%200226-559 | PKS 0226-559 known as PMN J0228-5546 is a quasar located in the constellation Horologium. At the redshift of 2.464, the object is roughly 10.6 billion light-years from Earth.
Characteristics
PKS 0226-559 contains a flat-spectrum radio source found brighter than S4.8 GHz=65 mJy. It is classified as a blazar, a type of powerful extragalactic object shooting out an astrophysical jet towards Earth's direction with a jet axis of ≲20° with strong variability across electro-magnetic spectrum. Such blazars like PKS 0226-559 have a rapid broad-band flux density and polarisation variability, with fast superluminal motion, and a high degree of polarisation. There are two classifications based on the presence of emission lines. The first classification are BL Lacertae objects with weak or emission lines absent. The second classification are flat-spectrum radio quasars (FSRQs) with strong emission lines, whom PKS 0226-559 belongs to.
The quasar is known to have a non-thermal emission in which from the jets, accessible bands of the electromagnetic spectrum can be seen, right up to high energy (HE; >100 MeV) and very high energy reaching up to (VHE; >100 MeV) in γ-ray bands. The broad-band spectral energy distribution (SED) in PKS 0226-559 shows two broad humps features, in which the synchrotron peak frequency (ν S peak) in PKS 0226-559 is positioned between 1012.5 and 1014.5 Hz.
According to observations conducted from the Large Area Telescope, one of the instruments has found that PKS 0226-559 shows an increasing gamma-ray emission from a source. It is believed that the accretion of matter is responsible for powering emission into the supermassive black hole in PKS 0226–559.
PKS 0226-559 has a power-law index of p = 1.56 ± 0.064; this signifies a flux variation, which in the 0.3–10 keV band, the weakest sources tend to exhibit fluxes on the order of (1.06 ± 0.32) × 10−13 erg cm−2s−1, while the brighter source reaches up to (2.96 ± 0.02) × 10−11 erg cm−2s−1, while majority of the sources exhibits a soft photon index.
The bolometric luminosity of PKS 0226-559 is found to exceed 1048 erg s−1 with γ-ray flux ranging between 4.84 × 10−10 to 1.50 × 10−7 photon cm-2 s-1. This allows it to be observed even located at very high redshift. Distant blazars like PKS 0226–559, are particularly interesting, as since the study offers insights how supermassive black holes form and evolve overtime, as well as proving insight to relativistic jets, and the connections between accretion discs and jets. Moreover, their γ-ray emission is important for probing the early universe given γ-ray emission from distant blazars undergoes attenuation via γγ absorption when they interact with extragalactic background light (EBL) photons, that enables observations constraining the EBL's density.
References
Quasars
Blazars
Horologium (constellation)
Active galaxies | PKS 0226-559 | [
"Astronomy"
] | 751 | [
"Constellations",
"Horologium (constellation)"
] |
77,088,159 | https://en.wikipedia.org/wiki/Jurusania | Jurusania is a genus of fossil stromatolite-forming cyanobacteria from the late Riphean to Vendian stages of the Neoproterozoic era.
See also
List of fossil stromatolites
References
Proterozoic life
Prehistoric bacteria
Cyanobacteria genera
Fossil taxa described in 1963 | Jurusania | [
"Biology"
] | 70 | [
"Prehistoric bacteria",
"Bacteria"
] |
77,088,374 | https://en.wikipedia.org/wiki/Conophyton | Conophyton is a genus of stromatolite-forming cyanobacteria from the Neoproterozoic era. Fossils have been found in many countries, including Australia, India, China and Russia.
See also
List of fossil stromatolites
References
Proterozoic life
Prehistoric bacteria
Cyanobacteria genera
Fossil taxa described in 1937 | Conophyton | [
"Biology"
] | 76 | [
"Prehistoric bacteria",
"Bacteria"
] |
77,088,844 | https://en.wikipedia.org/wiki/Bryan%20Adey | Bryan Tyrone Adey (born 20 December 1972 in Berwick, Nova Scotia, Canada) is a Swiss - Canadian civil engineer, full professor at the ETH Zurich, deputy head of the Department of Civil, Environmental and Geomatic Engineering (D-BAUG) at ETH Zurich, and co-founder of Carmentae Infrastructure Management.
Early life and education
Adey obtained his Doctorate in Civil Engineering from the EPF Lausanne in 2002, his Master of Science in Structural Engineering from the University of Alberta, Edmonton, Canada in 1997, his Bachelor of Engineering from Dalhousie University, Halifax, Canada in 1995, and his Certificate of Applied Science from Acadia University, Wolfville, Canada in 1992. He has been living in Switzerland since 1998.
Academic career
Adey joined the Institute for Construction and Infrastructure Management in the D-BAUG on Jan 1, 2010, as an associate professor. He was appointed full professor on Jan 1, 2018.
Between 2010 and 2023, Adey was the head or deputy head of the Institute for Construction and Infrastructure Management (IBI) at ETH Zurich.
Between 2020 and 2022, he was Director of Studies for the Curriculum Spatial Development & Infrastructure Systems (MSc) of D-BAUG at ETH Zurich and since 2022 he is the Deputy Head of D-BAUG at ETH Zurich. He is also a Principal Investigator for the Module Adaptive Mobility, Infrastructure, and Landscape (AMIL) in the ETH-Hub for the Future Cities Lab Global (FCL-Global) at the Singapore-ETH Centre.
Adey is also on the editorial board of the Journal of Infrastructure Asset Management and the Journal of Infrastructure Systems.
Research contributions
Adey's research is focused on improving the effectiveness and efficiency of infrastructure management. This includes the definition and standardization of the infrastructure management process, from setting goals to determining optimal monitoring and intervention programs and evaluating the performance of infrastructure management organizations. It also includes the automation of parts of the infrastructure management process, e.g., the determination of optimal intervention strategies for single infrastructure objects and the development of algorithms to generate network intervention plans that maximize net benefit. Other themes of his research are estimating the risk related to infrastructure, including estimating infrastructure behavior when subject to extreme events, estimating the resilience of the infrastructure systems including consideration of the infrastructure, the environment in which it is embedded and the responsible managing organizations, and estimating the optimal ways to restore infrastructure following extreme events. Adey works on infrastructure management issues related to many types of infrastructure, including road networks, rail networks, water distribution networks, sewer networks and building portfolios.
Adey regularly participates as a speaker at conferences, symposiums, and workshops on infrastructure management issues, such as the International Symposium for Infrastructure Asset Management and the International Forum on Engineering Decision Making and contributes to UN and OECD events .
Adey has been actively involved in writing international and national codes and guidelines.
This includes leading:
The writing of the United Nations Stress Test Framework through the Economic Commission for Europe, Inland Transport Committee, Working Party on Transport Trends and Economics, Group of Experts on Assessment of Climate Change, Impacts and Adaptation for Inland Transport ECE/TRANS/WP.5/GE.3/2023/3, which was published in 2024.
The revision of Swiss Code: SN 640 900 Maintenance management: Base code, as the president of the code and research committee 4.3 of the Swiss Association of Road and Transportation Experts, which was published in 2022.
The writing of the CEN pre-code CEN/CLC/WS 018 "Guidelines for the assessment of the resilience of transport infrastructure to potentially disruptive events", which was published in 2021.
Teaching
Adey's teaching is focused on developing infrastructure managers that are equipped to both professionally management infrastructure and to enable automation of parts of it in the organizations in which they will work. His lectures include Systems Engineering; Infrastructure Management 1: Process; Infrastructure Management 2: Evaluation tools; Infrastructure Management 3: Optimization tools; Project Management and Infrastructure Planning.
Consulting activity
After leaving the EPF Lausanne in 2002, Adey co-founded the company Infrastructure Management Consultants with Rade Hajdin and worked as its vice president from 2003 to 2009. In 2016, he co-founded Carmentae Infrastructure Management with Jürgen Hackl and Clemens Kielhauser.The consulting company principally focuses on transforming infrastructure asset management within organisations who manage large amounts of public infrastructure, including road networks, rail networks, water distribution networks, sewer networks and building portfolios. The company is mainly active in Switzerland and the United Kingdom, with notable work on the Sustainable Investment Decision Making transformation of Scottish Water.
Publications (selected)
Adey, B.T., Martani, C., Hackl, J., (2022), Investing in water supply resilience considering uncertainty and management flexibility, Smart Infrastructure and Construction, 175(3), pp. 104–115, DOI: 10.1680/jsmic.21.00005.
Burkhalter, M., Adey, B.T., (2022), Assessing the effects of closure free periods on railway intervention costs and service, Infrastructure Systems 8(3), 04022015-1, DOI 10.1061/(ASCE)IS.1943-555X.0000692.
Burkhalter, M., Adey, B.T., (2022), Digitalising the determination of railway infrastructure intervention programs: A network optimisation model, Infrastructure Systems, 8(2), 04022012-1-15 DOI: 10.1061/(ASCE)IS.1943-555X.0000681.
Adey, B.T., Martani, C., Kielhauser, C., Robles Urqulijo, I., Papathanasiou, N., Burkhalter M., (2021), Estimating, and setting targets for, the resilience of transport infrastructure, Special Issue: Resilient infrastructure for improved disaster management, Infrastructure Asset Management, 8(4), 167-190, DOI: 10.1680/jinam.20.00011.
Kerwin, S., Adey, B.T., (2020), Optimal Intervention Planning: A Bottom-Up Approach to Renewing Aging Water Infrastructure, Water Resources Planning and Management, 146(7): 04020044, DOI: 10.1061/(ASCE)WR.1943-5452.0001217.
Kielhauser, C., Adey, B.T., (2020), Determination of intervention programs for multiple municipal infrastructure networks: Considering network operator and service costs, Sustainable and Resilient Infrastructure, 5(1-2), 49-61, DOI 10.1080/23789689.2018.1497879.
Adey, B.T., Martani, C., Papathanasiou, N., Burkhalter, M., (2019), Principles of estimating and communicating the risk of neglecting maintenance, Infrastructure Asset Management, 6(2), pp. 109–128; DOI: 10.1680/jinam.18.00027.
Adey, B.T., (2019), A road infrastructure asset management process: Gains in efficiency and effectiveness, Infrastructure Asset Management, 6(1), March 2019, pp. 2-14, DOI: 10.1680/jinam.17.00018.
Hackl, J., Lam, J.C., Heitzler, M., Adey, B.T., Hurni, L., (2018), Estimating network related risks: a methodology and an application for roads, Natural Hazards and Earth System Sciences, 18, 2273–2293 DOI: 10.5194/nhess-18-2273-2018.
Kielhauser, C., Martani, C., Adey, B.T., (2018), Development of intervention programs for inland waterway networks using genetic algorithms, Structure and Infrastructure Engineering 14(5), 550-564, DOI: 10.1080/15732479.2017.1373299.
External links
Bryan Adey profile at the Chair of Infrastructure Management, ETH Zurich
Bryan Adey publications indexed by Google Scholar
References
Academic staff of ETH Zurich
Civil engineers
Living people
1972 births | Bryan Adey | [
"Engineering"
] | 1,755 | [
"Civil engineering",
"Civil engineers"
] |
77,088,884 | https://en.wikipedia.org/wiki/Kyosti%20Vilho%20Sarkanen | Kyösti Vilho Sarkanen (1921–1990) was a Finnish-American organic chemist and wood scientist, who served as a Professor at the University of Washington in Seattle. He was the honorary recipient of the Anselme Payen Award in 1979 from the American Chemical Society, and an elected fellow of the International Academy of Wood Science.
Sarkanen was born and grew up in Helsinki. He did his undergraduate studies in chemistry at the University of Helsinki. Later in the years 1947–1951, he was employed at the Finnish Pulp and Paper Research Institute.
He afterwards left for the US and completed his MSc degree in 1952, followed by the Doctor of Philosophy (PhD) degree in the field of organic (lignin) chemistry in 1956. Both degrees were granted from the State University of New York, College of Forestry at Syracuse University, under the direction of Professor Conrad Schuerch. Following that, Sarkanen assumed an academic position at the College of Forestry at the University of Washington in 1959, where he dedicated his efforts to both pedagogy and scholarly research until his retirement in 1988.
His research contributions in wood chemistry, particularly lignin chemistry, have been recorded and widely acclaimed. During his career, Sarkanen authored many publications on the subject of wood chemistry, and his contributions earned him several awards in recognition of his scholarly achievements. In addition to the Anselme Payen Award, Sarkanen received the Gadolin Medal Award from the Society of Finnish Chemists in 1988, and also (posthumously) the Paul W. Magnabosco Outstanding Member Award of the TAPPI in 1991. He has held more than 1,700 citations for his research works in Scopus.
Selected works
Lignins: Occurrence, formation, structure and reactions; edited by K. V. Sarkanen and C. H. Ludwig, John Wiley & Sons, Inc., New York, 1971
References
External links
Scopus
1921 births
1990 deaths
Wood scientists
Fellows of the International Academy of Wood Science
Finnish emigrants to the United States
Scientists from Helsinki
State University of New York College of Environmental Science and Forestry alumni
University of Washington faculty | Kyosti Vilho Sarkanen | [
"Materials_science"
] | 434 | [
"Wood sciences",
"Wood scientists"
] |
77,089,548 | https://en.wikipedia.org/wiki/N-Propylmagnesium%20bromide | n-Propylmagnesium bromide, often referred to as simply propylmagnesium bromide, is an organomagnesium compound with the chemical formula . As the Grignard reagent derived from 1-bromopropane, it is used for the n-propylation of electrophiles in organic synthesis.
Properties
Like all Grignard reagents, propylmagnesium bromide is a strong electrophile, sensitive to both water and air.
The propylmagnesium halides are the simplest Grignard reagents to exhibit isomerism. Isopropylmagnesium chloride is the primary synthetic equivalent of the isopropyl group.
n-Propylmagnesium bromide is soluble in ether, tetrahydrofuran, and toluene.
Synthesis
Synthesis is analogous to other saturated alkyl Grignard reagents. A solution of 1-bromopropane in ether - typically diethyl ether or tetrahydrofuran - is treated with magnesium, which inserts itself into the organohalogen bond. As both the magnesium metal and the product are sensitive to water, the reaction must take place in anhydrous conditions.
While the product is often portrayed as simply , in reality it will quickly form a tetrahedral coordination complex with the Lewis basic solvent, centred on the magnesium atom:
Applications
Propylmagnesium bromide is used in the Grignard reaction to introduce propyl groups to nucleophiles.
References
Organomagnesium compounds | N-Propylmagnesium bromide | [
"Chemistry"
] | 332 | [
"Organomagnesium compounds",
"Reagents for organic chemistry"
] |
77,090,277 | https://en.wikipedia.org/wiki/NGC%202935 | NGC 2935 is a large intermediate spiral galaxy located in the constellation Hydra. Its speed relative to the cosmic microwave background is 2,601 ± 23 km/s, which corresponds to a Hubble distance of 38.4 ± 2.7 Mpc (~125 million ly). It was discovered by German-British astronomer William Herschel on 20 March 1786.
NGC 2935 was used by Gérard de Vaucouleurs as a galaxy of morphological type (R2')SAB(s)b in his galaxy atlas. The luminosity class of NGC 2935 is II and it has a broad HI line. In addition, it is a star-forming burst galaxy.
To date, 29 studies and measurements based on redshift give a distance of 27.890 ± 3.962 Mpc (~91 million ly), which is outside the Hubble distance values. Note that it is with the average value of independent measurements, when they exist, that the NASA/IPAC database calculates the diameter of a galaxy and that consequently the diameter of NGC 2935 could be approximately 78, 1 kpc (~255,000 ly) if we used the Hubble distance to calculate it.
Nuclei disk
Observations from the Hubble Space Telescope have concluded that a star-forming disk is present around the core of NGC 2935. The size of its semi-major axis is estimated at 530 pc (~1730 light years) at the estimated distance of this galaxy.
Supernovae
Four supernovae have been discovered in NGC 2935:
SN 1975F (type unknown, mag. 15) was discovered on 11 June 1975, by Yvonne Dunlap and Justus R. Dunlap of the Corralitos Observatory at Northwestern University.
SN 1996Z (type Ia, mag. 16) was discovered on 16 May 1996 by Wayne Johnson.
SN 2021mwj (type II, mag. 17.7) was discovered on 21 May 2021 by ATLAS.
SN 2021aczp (type II, mag. 18.9) was discovered on 1 November 2021 by ATLAS.
NGC 2935 Group
NGC 2935 is part of a small group of three galaxies named after it. The other two galaxies in the NGC 2935 group are NGC 2983 and NGC 2986.
See also
List of NGC objects (2001–3000)
New General Catalogue
List of spiral galaxies
External links
NGC 2935 at NASA/IPAC
NGC 2935 at SIMBAD
NGC_2935 at LEDA
References
2935
Spiral galaxies
Hydra (constellation)
Galaxies
17860320
Discoveries by William Herschel
027351
565-23
-03-25-011
09344-2054 | NGC 2935 | [
"Astronomy"
] | 557 | [
"Hydra (constellation)",
"Constellations"
] |
77,090,495 | https://en.wikipedia.org/wiki/NGC%202792 | NGC 2792 is a planetary nebula located in the constellation Vela. NGC 2792 was discovered by British astronomer John Herschel in 1835.
Observation
With an apparent visual magnitude of 11.6, you must use a telescope with an aperture of at least 200 mm to observe it.
Characteristics
Distance, size and speed
Two very similar distances are indicated on the SIMBAD database: 3.086 ± 0.617 kpc (~10,100 ly) and approximately 3050 pc (~9,950 ly).
The apparent size of the nebula is 0.350 × 0.315, which, given the distance of 3,086 ± 617 pc and through simple calculation, equates to an actual size of 1.02 ± 0.20 al × 0 .92 ± 0.18 ly.
Two identical speed values are also indicated on SIMBAD, i.e. 14.0 ± 5.0 km/s. According to a more recent publication (2023) the speed of the nebula is 12.7 ± 8 km/s.
Age
The kinematic age of a planetary nebula can be estimated from its expansion speed. According to González-Santamaría and his colleagues, the expansion speed of NGC 2792 is 20 km/s, which gives it a kinematic age of 3.5 thousand years. According to a more recent publication, its expansion speed is 20.2 km/s.
According to González-Santamaría, it has been approximately 50,860 years since the star left the asymptotic giant branch and the nebula enveloping it reached 1% of the mass of the progenitor.
Central star
The visual magnitude of this star is equal to 16.74 and its mass is estimated at 1.163 solar masses. The radius of the nebula is estimated at 0.108 pc.
See also
List of planetary nebulae
List of NGC objects (2001–3000)
New General Catalogue
External links
NGC 2792 at NASA/IPAC
NGC 2792 at SIMBAD
NGC 2792 at LEDA
NGC 2792 at SEDS
References
Planetary nebulae
Vela (constellation)
2792
Discoveries by John Herschel | NGC 2792 | [
"Astronomy"
] | 445 | [
"Vela (constellation)",
"Constellations"
] |
77,090,743 | https://en.wikipedia.org/wiki/UNCOVER-z12 | UNCOVER-z12 is a high-redshift Lyman-break galaxy discovered by the James Webb Space Telescope (JWST) during NIRCam imaging for the JWST Ultradeep NIRSpec and NIRCam Observations before the Epoch of Reionization (UNCOVER) project in November 2023. UNCOVER-z12 is within the Abell 2744 supercluster in the constellation Sculptor. It is the 5th-most distant object ever discovered as of 2024, and is estimated to be 32.21 giga-lightyears from Earth.
Morphology
UNCOVER-z12 is a Lyman-Break galaxy. Due to the recent discovery date, not much more is known about the galaxy itself.
Discovery
UNCOVER-z12 was first observed when large amounts of gravitational lensing from Abell 2744 made the galaxy visible. Abell 2744 is around 3.5 billion light-years away from the Milky Way.
The gravity of Abell 2744 warps the fabric of space-time sufficiently to magnify the light of more faraway galaxies. The James Webb Space Telescope used the gravitational lensing to discover UNCOVER-z12, and further studies of deep galaxies located within Abell 2744 are currently ongoing.
UNCOVER-z13
UNCOVER-z13 is a second, more far-away galaxy that was located on November 14, 2023, using the same systems. It has a redshift of 13, making it the 3rd most distant object ever discovered in the observable universe.
See also
List of the most distant astronomical objects
Maisie's Galaxy, another extremely distant galaxy
GLASS-z12, an extremely distant galaxy with a similar redshift
References
Galaxies
Sculptor (constellation)
Discoveries by the James Webb Space Telescope | UNCOVER-z12 | [
"Astronomy"
] | 357 | [
"Galaxies",
"Astronomical objects",
"Constellations",
"Sculptor (constellation)"
] |
77,091,094 | https://en.wikipedia.org/wiki/2%2C4%2C6-Tris%28dimethylaminomethyl%29phenol | 2,4,6-Tris(dimethylaminomethyl)phenol is an aromatic organic chemical that has tertiary amine and phenolic hydroxyl functionality in the same molecule. The formula is C15H27N3O and the CAS Registry Number is 90-72-2. It is REACH registered and the European Community Number is 202-013-9.
Uses
A key use is as a catalyst for epoxy resin chemistry. It can be used as a homopolymerization catalyst for epoxy resins and also as an accelerator with epoxy resin curing agents. It is then further used in coatings, sealants, composites, adhesives and elastomers. It has been stated that it is probably the most widely used room temperature accelerator for two-component epoxy resin systems. The kinetics of curing with and without this accelerator have been extensively studied. It is the usual benchmark or control used when other catalysts and accelerators are being developed and tested.
In addition to its use in epoxy chemistry, it is also used in polyurethane chemistry for example by grafting the molecule into the polymer backbone. It is also used as a trimerization catalyst with polymeric MDI.
Polyether ether ketones may also be grafted with the molecule which then finds use in lithium batteries.
The high functionality of the molecule means it can be used to complex some transition metals and this has also been studied.
Often cited weaknesses are yellowing and odor.
Manufacture
The material is a Mannich base and is manufactured by reacting phenol, formaldehyde and dimethylamine in a reactor under vacuum and removing the water produced.
Toxicity
It is classed as a high volume chemical and as such, its toxicity profile has been extensively studied.
References
Further reading
Tertiary amines
Phenols
Catalysts
Dimethylamino compounds | 2,4,6-Tris(dimethylaminomethyl)phenol | [
"Chemistry"
] | 392 | [
"Catalysis",
"Catalysts",
"Chemical kinetics"
] |
77,091,437 | https://en.wikipedia.org/wiki/Alkylidene%20group | In organic chemistry, alkylidene is a general term for divalent functional groups of the form , where each R is an alkane or hydrogen. They can be considered the functional group corresponding to mono- or disubstituted divalent carbenes (known as alkylidenes), or as the result of removing two hydrogen atoms from the same carbon atom in an alkane.
The simplest alkylidene group is the methylidene group, . This is also known by the common name methylene, which can also refer to the methylene bridge group or the diradical carbene .
In organometallic chemistry, divalent ligands are referred to as carbenes, with the term "alkylidene" referring specifically to the narrower class of Schrock carbenes.
Nomenclature
In standard IUPAC nomenclature, alkylidene groups are named by replacing the -yl in the corresponding alkyl group with -ylidene. This practice is also often extended to common names. For example, the isopropyl group (IUPAC: prop-2-yl) corresponds to the isopropylidene group (IUPAC: prop-2-ylidene).
The group is not typically used in common names of branched alkenes - e.g. 3-methylenepentane, the simplest compound that systematically includes an alkylidene group, is commonly known as 2-ethyl-1-butene. Some authors define the primary chain of an alkene as the one containing the double bond(s), and thus alkylidene groups are only named in branched polyenes. The alkylidene substituent is always named explicitly in cyclic compounds, of which the simplest is methylenecyclopropane.
Conversely, common names of many classes of compounds use alkylidenes in their nomenclature, even though many of them do not formally contain the alkylidene group , instead containing a substituted methylene bridge .
Examples include geminal disubstituted alkanes, such as 1,1-dichloroethane being known as ethylidene dichloride (compare 1,2-dichloroethane's common name of ethylene dichloride); and cyclic ketals such as solketal and Meldrum's acid, also known respectively as isopropylidene glycerol and isopropylidene malonate. The latter two are both examples of acetonides, collectively also known as isopropylidene ketals.
Compounds
Ketenes are compounds of alkylidene and carbonyl. Alkylidene ketenes are, as the name suggests, further composition of alkylidenes and ketenes, containing multiple consecutive bonds.
In organometallic chemistry, double bonded carbons are the defining characteristic of transition metal carbene complexes, where they are typically referred to as carbene ligands. In this context, "alkylidene" refers specifically to Schrock carbenes, in which both the metal and carbon atoms are in the triplet state and form a true double bond (contrast Fischer carbenes, in which the atoms are in the singlet state).
Reactions
The distinction between alkylidenes and alkenes (or alkenyl groups) is semantic in organic chemistry. The compounds are isomeric, defined by the presence of a carbon-carbon double bond, and undergo similar reactions; thus, reactions involving alkylidene groups are typically described using the broader class of alkenes, even those which directly introduce a substituent (e.g. the Wittig reaction).
Isomerization of alkylidenes yields alkenes and alkenyls, and vice versa, through relocation of the double bond. Isomerization of alkenyl compounds is one route to alkylidene compounds, such as the production of ethylidene norbornene from vinyl norbornene.
In organometallic chemistry, alkylidenes (as Schrock carbenes) possess nucleophilic carbon atoms. They thus form adducts with Lewis acids, and undergo a Wittig-like reaction with carbonyls to yield alkenes (the archetypal example being the alkylidene intermediate yielded by Tebbe's reagent).
Notes
References
Organic chemistry | Alkylidene group | [
"Chemistry"
] | 928 | [
"nan"
] |
77,091,723 | https://en.wikipedia.org/wiki/Siren%20Tour | A Siren Tour was a night-time mission by the RAF Bomber Command, mostly in northern Cambridgeshire, involving three or four two-engined fast bomber aircraft, to set the German air-raid sirens off in the middle of the night, so waking up the whole German town at three o'clock in the morning. The purpose was to cause nuisance, and sleep deprivation.
History
The raids were carried out by RAF bases in Cambridgeshire and Huntingdonshire, from the Light Night Striking Force. These were small bombing raids, often in the middle of the night, to get the population in the German town out of bed, on the sound of a Fliegeralarm, to intentionally upset the nocturnal rhythm by false alarms of the German factory workers; night shift workers would have to go to the shelters, and day shift workers had their sleep disturbed. It was to make German citizens mentally unfit for work.
Although these were small raids, the raids were quite irritating for German people. The two-engined bomber aircraft were largely invincible from any attack; for the first six hundred Mosquito missions over Germany, only one was shot down.
Once the bomb was dropped, the twin-engined bomber could return to Cambridgeshire at 400 mph, being invisible to radar.
Operation
The raids apparently began on 30 November 1943, or thereabouts. There were around three aircraft in each raid, but with three or four targets. Each target would receive a 500 lb bomb from the aircraft.
Siren tours would continue throughout early 1945. The aircraft took off from RAF Upwood, RAF Graveley, RAF Little Staughton
RAF Gransden Lodge, RAF Oakington,
and RAF Wyton, all part of 8 Group (PFF).
See also
de Havilland Mosquito operational history
References
De Havilland Mosquito
Military history of Cambridgeshire
Military history of Huntingdonshire
Night flying
Sleeplessness and sleep deprivation
Sirens
World War II strategic bombing of Germany | Siren Tour | [
"Biology"
] | 380 | [
"Behavior",
"Sleep",
"Sleeplessness and sleep deprivation"
] |
77,092,886 | https://en.wikipedia.org/wiki/Squaramide%20catalysis | Within the area of organocatalysis, squaramide catalysis describes the use of squaramides to accelerate and stereochemically alter organic transformations. The effects arise through hydrogen-bonding interactions between the substrate and the squaramide, unlike classic catalysts, and is thus a type of hydrogen-bond catalyst. The scope of these small-molecule H-bond donors termed squaramide organocatalysis covers both non-stereoselective and stereoselective applications.
Structure
A squaramide organocatalyst typically contains the squaramide group and a hydrogen bond donor which is usually a tertiary amine group. The 3,5-bis(trifluoromethyl)phenyl-group is commonly used for the R group. For enantioselective squaramide catalysis, chirality is induced via the tertiary amine group. There are cases where both sides of the squaramide are tertiary amines.
Catalyst-substrate interactions
The interaction between the substrate and the catalyst can be seen in the image above, with the electrophile being bound to the squaramide part and the protonated nucleophile to the amine part (which increases nucleophilicity). However, it must be noted that the position of the nucleophile and electrophile switch when the electrophile can only form one hydrogen bond, as in the case of most imines.
Advantages of squaramide organocatalysts
Squaramide catalysts are easily prepared from starting materials like methyl squarate, possess high activities under low catalyst loadings. Squaramide catalysis can be a replacement for thiourea organocatalysis in some scenarios. Squaramides have higher affinity for halide ions than thiourea.Aqueous mediums can be used.
Scope
H-bond accepting substrates include carbonyl compounds imines, Michael acceptors, and epoxides. The nucleophile can be nitroalkanes, enolates, and even phenols (resulting in electrophilic aromatic substitution). Subsequent cascade reactions are possible.
History
Squaramides have been synthesized in 1966. Squaramide catalysts are developed in 2008 by Jeremiah P. Malerich, Koji Hagihara, and Viresh H. Rawal.
Catalysts
From the general structure of squaramide catalysts, a number of catalysts have been developed, most with the aim to enable chiral catalysis.
See also
Organocatalysis
Hydrogen-bond catalysis
Thiourea catalysis
Squaramide
References
Catalysis
Organic chemistry | Squaramide catalysis | [
"Chemistry"
] | 560 | [
"Catalysis",
"Chemical kinetics",
"nan"
] |
77,093,106 | https://en.wikipedia.org/wiki/List%20of%20fossil%20stromatolite%20taxa | This is a list of all extinct cyanobacteria genera that formed stromatolites.
References
Proterozoic life
Prehistoric bacteria
Cyanobacteria genera | List of fossil stromatolite taxa | [
"Biology"
] | 37 | [
"Prehistoric bacteria",
"Bacteria"
] |
77,093,520 | https://en.wikipedia.org/wiki/NGC%203290 | NGC 3290 (also known as Arp 53) is a large and relatively distant intermediate spiral galaxy located in the constellation Hydra. Its speed relative to the cosmic microwave background is 10,937 ± 27 km/s, which corresponds to a Hubble distance of 161 ± 11 Mpc (~525 million ly). NGC 3290 was discovered by American astronomer Francis Leavenworth in 1886.
NGC 3290 is cataloged in the Arp catalog as Arp 53. Halton Arp divided his catalog of unusual galaxies into groups based on purely morphological criteria. This galaxy belongs to the class of spiral galaxies with a small, high-surface-brightness companion on one arm.
The luminosity class of NGC 3280 is II-III and it has a broad HI line. It also contains regions of ionized hydrogen. Moreover, NGC 3290 has an apparent magnitude of 13.5.
See also
List of NGC objects (3001–4000)
New General Catalogue
External links
NGC 3290 at NASA/IPAC
NGC 3290 at SIMBAD
References
Hydra (constellation)
3290
Spiral galaxies | NGC 3290 | [
"Astronomy"
] | 224 | [
"Hydra (constellation)",
"Constellations"
] |
77,093,617 | https://en.wikipedia.org/wiki/IC%201296 | IC 1296 is an extremely faint barred spiral galaxy of Hubble-type SBbc in the constellation Lyra in the northern sky. It is estimated to be 238 million light-years from the Milky Way and about 120,000 light-years in diameter.
IC 1296 is only 4 arc minutes away from the well-known Ring Nebula in the night sky. Planetary nebulae and galaxies are rarely observed together because planetary nebulae are galactic objects and are concentrated toward our galactic center, where extragalactic objects – such as distant galaxies – are rarely observed due to absorption by gas and dust.
The astronomical object was discovered on October 2, 1893, by Edward Emerson Barnard. In August 2013, supernova SN2013ev was discovered in the southern spiral arm of IC 1296.
See also
List of spiral galaxies
External links
IC 1296 at SIMBAD
References
Spiral galaxies
Barred spiral galaxies
Spitzer Space Telescope
Lyra | IC 1296 | [
"Astronomy"
] | 186 | [
"Lyra",
"Space telescopes",
"Constellations",
"Spitzer Space Telescope"
] |
77,093,779 | https://en.wikipedia.org/wiki/NGC%204712 | NGC 4712 is a spiral galaxy located in the constellation Coma Berenices. Its speed relative to the cosmic microwave background is 4,664 ± 20 km/s, which corresponds to a Hubble distance of 68.8 ± 4.8 Mpc (~224 million ly). NGC 4712 was discovered by German-British astronomer John Herschel in 1832.
The luminosity class of NGC 4712 is II-III and it has a broad HI line. It also contains regions of ionized hydrogen.
To date, around ten measurements not based on redshift give a distance of 63.640 ± 16.932 Mpc (~208 million ly), which is within the distance values of Hubble. Note, however, that it is with the average value of independent measurements, when they exist, that the NASA/IPAC database calculates the diameter of a galaxy and that consequently the diameter of NGC 4712 could be approximately 51 .4 kpc (~168,000 ly) if we used the Hubble distance to calculate it.
According to Vaucouleur and Harold Corwin, NGC 4712 and NGC 4725 form a pair of galaxies. However, like several others mentioned in this article, these two galaxies are not an actual pair, because NGC 4725's radial velocity is 1,209 ± 1 km/s and is therefore much closer to the Milky Way. It is therefore an optical pair.
See also
List of spiral galaxies
List of NGC objects (4001–5000)
External links
NGC 4712 at NASA/IPAC
NGC 4712 at SIMBAD
NGC 4712 at LEDA
References
Coma Berenices
4712
Spiral galaxies | NGC 4712 | [
"Astronomy"
] | 346 | [
"Coma Berenices",
"Constellations"
] |
77,094,171 | https://en.wikipedia.org/wiki/PKS%200451-28 | PKS 0451-28 (full name PKS 0451-282), also known as MRC 0451-282, is a quasar located in the constellation of Caelum. Its redshift is 2.55, estimating the object to be located nearly 10.8 billion light-years away from Earth.
Characteristics
Observed by the 20-GHz Australia Telescope Compact Array radio survey, PKS 0451-28 is classified as a blazar. It is a type of an active extragalactic object launching out a relativistic astrophysical jet towards the direction of Earth with the observer's line of sight.
The emitted radiation from PKS 0451-28 shows a strong variability across its entire electro-magnetic spectrum. As a source of non-thermal emission, from radio to high energy (HE; >100 MeV) or very high energy (VHE; >100 GeV) γ-ray bands, the jets of PKS 0451-28 are known to cover the entire spectrum. This tend to vary in a short time-scales such as in minute scales within the γ-ray band causing an increase in luminosity. The flux variation in PKS 0451–28, the observed superluminal motion, high degrees of polarization, and other features observed are explained by the relativistic beaming effects.
Moreover, PKS 0451-28 is a flat-spectrum radio quasar (FSRQ). It has a strong emission lines (EW >5 Å) and contains a powerful radio source observed by NuSTAR, with a visual magnitude of 16.7 and redshift of 0.9, which its radio fluxes have been catalogued at 1.8 Jy at 5 GHz and 3 Jy at 31 GHz respectively.
Observations of PKS 0451-28
According to researchers, the γ-ray luminosity in PKS 0451-28 is found to exceed 1048 erg s−1 with the highest γ-ray luminosity of (5.54 ± 0.06) × 1048 erg s−1, that is estimated for another blazar, B3 1343+451. Naturally, compared to the distribution of all BL Lacs and FSRQs that are considered γ-ray-emitting, in the Γγ−Lγ plane, the blazars observed, are considered to occupy the highest luminosity range.
Interestingly, PKS 0451-28 appears as a bright X-ray emitter, but however does not have signs of distinguishable features in the X-ray band, only having a flux and photon index similar to those of the other considered sources in blazars. Along with other studied blazars like PKS 0537-286, PKS 1351-108, PKS 0438-43, PKS 0834-20 and TXS 0222+185, a thermal blue-bump component is found in PKS 0451–28, suggesting emission directly from its disc.
Researchers also noted the X-ray flux in PKS 0451-28 is known to be consistent, remaining at (9.52 ± 1.21) × 10−14 erg cm−2 s−1 compared to a few blazars like PKS 0438−43, whose X-ray flux was in a bright X-ray state on December 15, 2016, with a flux of (1.09 ± 0.16) × 10−11 erg cm−2 s−1 as compared with the flux of (1.30 ± 0.31) × 10−11 erg cm−2 s−1 in the quiescent state.
Moreover, the adaptively binned light curves for PKS 0451-28 shows show several episodes of γ-rays brightening, whereas the γ-ray flux increase within day scales is observed. The peak γ-ray flux of (2.20 ± 0.50) × 10−7 photon cm−2 s−1 in PKS 0451-28 is found to be above 163.2 MeV. During the observation, it has a MJD of 56968.60 ± 0.79 with 9.64σ, corresponding to a flux of (3.70 ± 0.84) × 10−7 photon cm−2 s−1 above 100 MeV. During this period, Γγ was 2.06 ± 0.19. This shows only the photon index of PKS 0451-28 varies in time; the variation is highly significant in which the blazar shows a value of P(χ2) ≤ 10−5.
Disc luminosity
The disc luminosity of PKS 0451-28 is estimated to be Ld ≃ (1.09−10.94) × 1046 erg s−1 according to researchers calculating the energetics of the considered source for the blazar by using modelling results.
Supermassive black hole and jet luminosity
The supermassive black hole in PKS 0451-28 has a solar mass of within (1.69−5.35) × 109 M⊙ as calculated by researchers through a traditional virial method. Around 5–16 percent is contributed by the Eddington luminosity.
As for jet power in PKS 0451–28, it is in the form of the magnetic field (LB) and relativistic electrons (Le). Researchers calculated the jet power as L = πR2c Γ2Ui, where Ui is either electron (Ue) or magnetic field (UB) energy density. Furthermore, the jet luminosity (defined as L = Le + LB) is ≤1.41 × 1046 erg s−1 for PKS 0451–28. It is found to be lower compared to the disc Ld ≃ (1.09−10.94) × 1046 erg s−1 although it has a significant correlation with the broad-line luminosity in the blazar, hence supporting the theory of jet power having a closer bond with accretion.
The jet power is found to have an approximate value of logLBLR ~ (0.98 ± 0.07)logPjet for all blazars including PKS 0451–28. The values are consistent with the theoretical predicted coefficient of logLBLR-logLjet relation. Results do support the jets in blazars like PKS 0451–28, are powered by energy extraction from both accretion and black hole spin as observed by Fermi. This finds PKS 0451-28 is a powerful blazar with high luminosity and of the same order calculated for other blazars studied both distant and nearby since the jet power do not differ substantially and those that are usually estimated for bright FSRQs.
References
Blazars
Quasars
Caelum
2824135
Active galaxies | PKS 0451-28 | [
"Astronomy"
] | 1,427 | [
"Caelum",
"Constellations"
] |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.