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🔗 Last universal ancestor

🔗 Biology 🔗 Genetics 🔗 Computational Biology 🔗 Evolutionary biology 🔗 Human Genetic History

The last universal common ancestor (LUCA), also called the last universal ancestor (LUA), or concestor, is the most recent population of organisms from which all organisms now living on Earth have a common descent, the most recent common ancestor of all current life on Earth. (A related concept is that of progenote.) LUCA is not thought to be the first life on Earth but only one of many early organisms, all the others becoming extinct.

While there is no specific fossil evidence of LUCA, it can be studied by comparing the genomes of all modern organisms, its descendants. By this means, a 2016 study identified a set of 355 genes most likely to have been present in LUCA. (However, some of those genes could have developed later, then spread universally by horizontal gene transfer between archaea and bacteria.) The genes describe a complex life form with many co-adapted features, including transcription and translation mechanisms to convert information from DNA to RNA to proteins. The study concluded that the LUCA probably lived in the high-temperature water of deep sea vents near ocean-floor magma flows.

Studies from 2000 to 2018 have suggested an increasingly ancient time for LUCA. In 2000, estimations suggested LUCA existed 3.5 to 3.8 billion years ago in the Paleoarchean era, a few hundred million years after the earliest fossil evidence of life, for which there are several candidates ranging in age from 3.48 to 4.28 billion years ago. A 2018 study from the University of Bristol, applying a molecular clock model, places the LUCA shortly after 4.5 billion years ago, within the Hadean.

Charles Darwin first proposed the theory of universal common descent through an evolutionary process in his book On the Origin of Species in 1859: "Therefore I should infer from analogy that probably all the organic beings which have ever lived on this earth have descended from some one primordial form, into which life was first breathed." Later biologists have separated the problem of the origin of life from that of the LUCA.

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🔗 Scottish Café

🔗 Mathematics 🔗 Books 🔗 Food and drink 🔗 Poland 🔗 Food and drink/Foodservice 🔗 Ukraine

The Scottish Café (Polish: Kawiarnia Szkocka) was a café in Lwów, Poland (now Lviv, Ukraine) where, in the 1930s and 1940s, mathematicians from the Lwów School of Mathematics collaboratively discussed research problems, particularly in functional analysis and topology.

Stanislaw Ulam recounts that the tables of the café had marble tops, so they could write in pencil, directly on the table, during their discussions. To keep the results from being lost, and after becoming annoyed with their writing directly on the table tops, Stefan Banach's wife provided the mathematicians with a large notebook, which was used for writing the problems and answers and eventually became known as the Scottish Book. The book—a collection of solved, unsolved, and even probably unsolvable problems—could be borrowed by any of the guests of the café. Solving any of the problems was rewarded with prizes, with the most difficult and challenging problems having expensive prizes (during the Great Depression and on the eve of World War II), such as a bottle of fine brandy.

For problem 153, which was later recognized as being closely related to Stefan Banach's "basis problem", Stanisław Mazur offered the prize of a live goose. This problem was solved only in 1972 by Per Enflo, who was presented with the live goose in a ceremony that was broadcast throughout Poland.

The café building now houses the Szkocka Restaurant & Bar (named for the original Scottish Café) and the Atlas Deluxe hotel at the street address of 27 Taras Shevchenko Prospekt.

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🔗 Organ harvesting from Falun Gong practitioners in China

🔗 Human rights 🔗 Medicine 🔗 Religion 🔗 Death 🔗 China 🔗 Religion/New religious movements 🔗 Religion/Falun Gong

Reports of forced organ harvesting from Falun Gong practitioners and other political prisoners in China have raised increasing concern within the international community. According to a report by former lawmaker David Kilgour, human rights campaigner David Matas and Victims of Communism Memorial Foundation researcher Ethan Gutmann, political prisoners, mainly Falun Gong practitioners, may be executed "on demand" in order to provide organs for transplant to recipients.

Reports on systematic organ harvesting from Falun Gong prisoners first emerged in 2006, though the practice is thought by some to have started six years earlier. Several researchers—most notably Matas, Kilgour and Gutmann—estimate that tens of thousands of Falun Gong prisoners of conscience have been killed to supply a lucrative trade in human organs and cadavers and that these abuses may be ongoing. These conclusions are based on a combination of statistical analysis; interviews with former prisoners, medical authorities and public security agents; and circumstantial evidence, such as the large number of Falun Gong practitioners detained extrajudicially in China and the profits to be made from selling organs.

The Chinese government long denied all accusations of organ harvesting. However, the failure of Chinese authorities to effectively address or refute the charges has drawn attention and public condemnation from some governments, international organizations and medical societies. The parliaments of Canada and the European Union, as well as the U.S. Senate and House of Representatives, have adopted resolutions condemning the forced organ harvesting from Falun Gong prisoners of conscience. United Nations Special Rapporteurs have called on the Chinese government to account for the sources of organs used in transplant practices, and the World Medical Association, the American Society of Transplantation and the Transplantation Society have called for sanctions on Chinese medical authorities. Several countries have also taken or considered measures to deter their citizens from travelling to China for the purpose of obtaining organs. A documentary on organ harvesting from Falun Gong practitioners, Human Harvest, received a 2014 Peabody Award recognizing excellence in broadcast journalism. China eventually admitted that it had engaged in systematic organ harvesting from death row prisoners, though it denies that such an organ harvesting program is ongoing.

🔗 TRIZ – Theory of Inventive Problem Solving

🔗 Education

TRIZ (; Russian: теория решения изобретательских задач, teoriya resheniya izobretatelskikh zadatch, literally: "theory of the resolution of invention-related tasks") is "a problem-solving, analysis and forecasting tool derived from the study of patterns of invention in the global patent literature". It was developed by the Soviet inventor and science-fiction author Genrich Altshuller (1926-1998) and his colleagues, beginning in 1946. In English the name is typically rendered as "the theory of inventive problem solving", and occasionally goes by the English acronym TIPS.

Following Altshuller's insight, the theory developed on a foundation of extensive research covering hundreds of thousands of inventions across many different fields to produce a theory which defines generalisable patterns in the nature of inventive solutions and the distinguishing characteristics of the problems that these inventions have overcome.

An important part of the theory has been devoted to revealing patterns of evolution and one of the objectives which has been pursued by leading practitioners of TRIZ has been the development of an algorithmic approach to the invention of new systems, and to the refinement of existing ones.

TRIZ includes a practical methodology, tool sets, a knowledge base, and model-based technology for generating innovative solutions for problem solving. It is useful for problem formulation, system analysis, failure analysis, and patterns of system evolution. There is a general similarity of purposes and methods with the field of pattern language, a cross discipline practice for explicitly describing and sharing holistic patterns of design.

The research has produced three primary findings:

  1. problems and solutions are repeated across industries and sciences
  2. patterns of technical evolution are also repeated across industries and sciences
  3. the innovations used scientific effects outside the field in which they were developed

TRIZ practitioners apply all these findings in order to create and to improve products, services, and systems.

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🔗 Muntzing

🔗 Technology 🔗 Electronics 🔗 Engineering 🔗 Industrial design

Muntzing is the practice and technique of reducing the components inside an electronic appliance to the minimum required for it to sufficiently function in most operating conditions, reducing design margins above minimum requirements toward zero. The term is named after the man who invented it, Earl "Madman" Muntz, a car and electronics salesman, who was not formally educated or trained in any science or engineering discipline.

In the 1940s and 1950s, television receivers were relatively new to the consumer market, and were more complex pieces of equipment than the radios which were then in popular use. TVs often contained upwards of 30 vacuum tubes, as well as transformers, rheostats, and other electronics. The consequence of high cost was high sales pricing, limiting potential for high-volume sales. Muntz expressed suspicion of complexity in circuit designs, and determined through simple trial and error that he could remove a significant number of electronic components from a circuit design and still end up with a monochrome TV that worked sufficiently well in urban areas, close to transmission towers where the broadcast signal was strong. He carried a pair of wire clippers, and when he felt that one of his builders was overengineering a circuit, he would begin snipping out some of the electronics components. When the TV stopped functioning, he would have the technician reinsert the last removed part. He would repeat the snipping in other portions of the circuit until he was satisfied in his simplification efforts, and then leave the TV as it was without further testing in more adverse conditions for signal reception.

As a result, he reduced his costs and increased his profits at the expense of poorer performance at locations more distant from urban centers. He reasoned that population density was higher in and near the urban centers where the TVs would work, and lower further out where the TVs would not work, so the Muntz TVs were adequate for a very large fraction of his customers. And for those further out, where the Muntz TVs did not work, those could be returned at the customer's additional effort and expense, and not Muntz's. He focused less resources in the product, intentionally accepting bare minimum performance quality, and focused more resources on advertising and sales promotions.

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🔗 Flocken Elektrowagen

🔗 Environment 🔗 Automobiles 🔗 Environment/Green vehicle

The Flocken Elektrowagen is a four-wheeled electric car designed by Andreas Flocken (1845–1913), manufactured in 1888 by Maschinenfabrik A. Flocken in Coburg. It is regarded as the first real electric car.

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🔗 Whipping Boy

🔗 European history

A whipping boy was a boy educated alongside a prince (or boy monarch) in early modern Europe, who received corporal punishment for the prince's transgressions in his presence. The prince was not punished himself because his royal status exceeded that of his tutor; seeing a friend punished would provide an equivalent motivation not to repeat the offence. An archaic proverb which captures a similar idea is "to beat a dog before a lion." Whipping was a common punishment of tutors at that time. There is little contemporary evidence for the existence of whipping boys, and evidence that some princes were indeed whipped by their tutors, although Nicholas Orme suggests that nobles might have been beaten less often than other pupils. Some historians regard whipping boys as entirely mythical; others suggest they applied only in the case of a boy king, protected by divine right, and not to mere princes.

In Renaissance humanism, Erasmus' treatises "The Education of a Christian Prince" (1516) and "Declamatio de pueris statim ac liberaliter instituendis" (1530) mention the inappropriateness of physical chastisement of princes, but do not mention proxy punishment. Hartley Coleridge wrote in 1852, "to be flogged by proxy was the exclusive privilege of royal blood. ... It was much coveted for the children of the poorer gentry, as the first step in the ladder of preferment." John Gough Nichols wrote in 1857, "the whole matter is somewhat legendary, and though certain vicarious or rather minatory punishments may have been occasionally adopted, it does not seem likely that any one individual among the King's schoolfellows should have been uniformly selected, whether he were in fault or not, as the victim or scape-goat of the royal misdemeanours". In current English, a "whipping boy" is a metaphor which may have a similar meaning to scapegoat, fall guy, or sacrificial lamb; alternatively it may mean a perennial loser or a victim of group bullying.

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🔗 What five simple habits can do over 35 years

🔗 Medicine 🔗 Medicine/Cardiology 🔗 Wales

The Caerphilly Heart Disease Study, also known as the Caerphilly Prospective Study (CaPS), is an epidemiological prospective cohort, set up in 1979 in a representative population sample drawn from Caerphilly, a typical small town in South Wales, UK.

The initial aim was to examine relationships between a wide range of social, lifestyle, dietary and other factors with incident vascular disease. Opportunity was also taken, in collaboration with a range of clinical and laboratory colleagues, to collect data on a wide range of factors with possible relevance to diseases other than vascular, and at the same time to collect clinical information on incident disease events. The study was initiated by Professor Peter Elwood, Director of the Medical Research Council (MRC) Epidemiology Unit for South Wales. The work has so far led to over 400 publications in the medical press.

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🔗 Information cascade

🔗 Economics

An Information cascade or informational cascade is a phenomenon described in behavioral economics and network theory in which a number of people make the same decision in a sequential fashion. It is similar to, but distinct from herd behavior.

An information cascade is generally accepted as a two-step process. For a cascade to begin an individual must encounter a scenario with a decision, typically a binary one. Second, outside factors can influence this decision (typically, through the observation of actions and their outcomes of other individuals in similar scenarios).

The two-step process of an informational cascade can be broken down into five basic components:

1. There is a decision to be made – for example; whether to adopt a new technology, wear a new style of clothing, eat in a new restaurant, or support a particular political position

2. A limited action space exists (e.g. an adopt/reject decision)

3. People make the decision sequentially, and each person can observe the choices made by those who acted earlier

4. Each person has some information aside from their own that helps guide their decision

5. A person can't directly observe the outside information that other people know, but he or she can make inferences about this information from what they do

Social perspectives of cascades, which suggest that agents may act irrationally (e.g., against what they think is optimal) when social pressures are great, exist as complements to the concept of information cascades. More often the problem is that the concept of an information cascade is confused with ideas that do not match the two key conditions of the process, such as social proof, information diffusion, and social influence. Indeed, the term information cascade has even been used to refer to such processes.

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🔗 Duenos Inscription

🔗 Classical Greece and Rome 🔗 Latin 🔗 Rome

The Duenos inscription is one of the earliest known Old Latin texts, variously dated from the 7th to the 5th century BC. It is inscribed on the sides of a kernos, in this case a trio of small globular vases adjoined by three clay struts. It was found by Heinrich Dressel in 1880 on the Quirinal Hill in Rome. The kernos is part of the collection of the Staatliche Museen in Berlin (inventory no. 30894,3).

The inscription is written right to left in three units, without spaces to separate words. It is difficult to translate, as some letters are hard to distinguish, particularly since they cannot always be deduced by context. The absence of spaces causes additional difficulty in assigning the letters to the respective words.

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