Random Articles (Page 54)

Have a deep view into what people are curious about.

🔗 Palmer Notation

🔗 Dentistry

Palmer notation (sometimes called the "Military System" and named for 19th-century American dentist Dr. Corydon Palmer from Warren, Ohio) is a dental notation (tooth numbering system). Despite the adoption of the FDI World Dental Federation notation (ISO 3950) in most of the world and by the World Health Organization, the Palmer notation continued to be the overwhelmingly preferred method used by orthodontists, dental students and practitioners in the United Kingdom as of 1998.

The notation was originally termed the Zsigmondy system after Hungarian dentist Adolf Zsigmondy, who developed the idea in 1861 using a Zsigmondy cross to record quadrants of tooth positions. Adult teeth were numbered 1 to 8, and the child primary dentition (also called deciduous, milk or baby teeth) were depicted with a quadrant grid using Roman numerals I, II, III, IV, V to number the teeth from the midline. Palmer changed this to A, B, C, D, E, which made it less confusing and less prone to errors in interpretation.

The Palmer notation consists of a symbol (⏌⎿ ⏋⎾) designating in which quadrant the tooth is found and a number indicating the position from the midline. Adult teeth are numbered 1 to 8, with deciduous (baby) teeth indicated by a letter A to E. Hence the left and right maxillary central incisor would have the same number, "1", but the right one would have the symbol "⏌" underneath it, while the left one would have "⎿".

Discussed on

🔗 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.

Discussed on

🔗 Reservoir computing

🔗 Computing

Reservoir computing is a framework for computation that may be viewed as an extension of neural networks. Typically an input signal is fed into a fixed (random) dynamical system called a reservoir and the dynamics of the reservoir map the input to a higher dimension. Then a simple readout mechanism is trained to read the state of the reservoir and map it to the desired output. The main benefit is that training is performed only at the readout stage and the reservoir is fixed. Liquid-state machines and echo state networks are two major types of reservoir computing. One important feature of this system is that it can use the computational power of naturally available systems which is different from the neural networks and it reduces the computational cost.

Discussed on

🔗 The Dreyfus affair

🔗 France 🔗 Military history 🔗 Politics 🔗 Military history/Intelligence 🔗 Judaism 🔗 Military history/French military history 🔗 Jewish history 🔗 European history 🔗 Military history/European military history

The Dreyfus Affair (French: l'affaire Dreyfus, pronounced [lafɛːʁ dʁɛfys]) was a political scandal that divided the Third French Republic from 1894 until its resolution in 1906. "The Affair", as it is known in French, has come to symbolise modern injustice in the Francophone world, and it remains one of the most notable examples of a complex miscarriage of justice and antisemitism. The role played by the press and public opinion proved influential in the conflict.

The scandal began in December 1894 when Captain Alfred Dreyfus was convicted of treason. Dreyfus was a 35-year-old Alsatian French artillery officer of Jewish descent. He was sentenced to life imprisonment for allegedly communicating French military secrets to the German Embassy in Paris, and was imprisoned on Devil's Island in French Guiana, where he spent nearly five years.

In 1896, evidence came to light—primarily through an investigation instigated by Georges Picquart, head of counter-espionage—which identified the real culprit as a French Army major named Ferdinand Walsin Esterhazy. When high-ranking military officials suppressed the new evidence, a military court unanimously acquitted Esterhazy after a trial lasting only two days. The Army laid additional charges against Dreyfus, based on forged documents. Subsequently, Émile Zola's open letter J'Accuse…!, stoked a growing movement of support for Dreyfus, putting pressure on the government to reopen the case.

In 1899, Dreyfus was returned to France for another trial. The intense political and judicial scandal that ensued divided French society between those who supported Dreyfus (now called "Dreyfusards"), such as Sarah Bernhardt, Anatole France, Henri Poincaré and Georges Clemenceau, and those who condemned him (the anti-Dreyfusards), such as Édouard Drumont, the director and publisher of the antisemitic newspaper La Libre Parole. The new trial resulted in another conviction and a 10-year sentence, but Dreyfus was pardoned and released. In 1906, Dreyfus was exonerated and reinstated as a major in the French Army. He served during the whole of World War I, ending his service with the rank of lieutenant-colonel. He died in 1935.

The affair from 1894 to 1906 divided France into pro-republican, anticlerical, Dreyfusards and pro-Army, mostly Catholic "anti-Dreyfusards". It embittered French politics and encouraged radicalisation.

Discussed on

🔗 Antarctic English

🔗 Linguistics 🔗 Antarctica 🔗 Languages 🔗 English Language

Antarctic English is a variety of the English language spoken by people living on the continent of Antarctica and within the subantarctic islands.: vii  Spoken primarily by scientists and workers in the Antarctic tourism industry, it consists of various unique words and is spoken with a unique accent. During the 19th and 20th centuries, Antarctic English was influenced by Spanish-speaking South Americans and Northern European explorers who introduced new words that continue to be used today.

Discussed on

🔗 Hebrew: the only language to revive from absolute 0 native speakers to Millions

🔗 Linguistics 🔗 Linguistics/Applied Linguistics 🔗 Judaism 🔗 Israel

The revival of the Hebrew language took place in Europe and Palestine toward the end of the 19th century and into the 20th century, through which the language's usage changed from the sacred language of Judaism to a spoken and written language used for daily life in Israel. The process began as a diversity of Jews started arriving and establishing themselves alongside the pre-existing Jewish community in the region of Palestine in the first half of the nineteenth century, when veteran Jews in Palestine (largely Arabic-speaking by that time) and the linguistically diverse newly arrived Jews all switched to use Hebrew as a lingua franca, the historical linguistic common denominator of all the Jewish groups. At the same time, a parallel development in Europe changed Hebrew from primarily a sacred liturgical language into a literary language which played a key role in the development of nationalist educational programs. Modern Hebrew was one of three official languages of Mandatory Palestine, and after the Israeli Declaration of Independence in 1948, one of two official languages of Israel, along with Modern Arabic. In July 2018, a new law made Hebrew the sole official language of the state of Israel, with Arabic having "special status". More than purely a linguistic process, the revival of Hebrew was utilized by Jewish modernization and political movements, and became a tenet of the ideology associated with settlement of the land, Zionism and Israeli policy.

The process of Hebrew's return to regular usage is unique; there are no other examples of a natural language without any native speakers subsequently acquiring several million native speakers, and no other examples of a sacred language becoming a national language with millions of "first language" speakers.

The language's revival eventually brought linguistic additions with it. While the initial leaders of the process insisted they were only continuing "from the place where Hebrew's vitality was ended", what was created represented a broader basis of language acceptance; it includes characteristics derived from all periods of Hebrew language, as well as from the non-Hebrew languages used by the long-established European, North African, and Middle Eastern Jewish communities, with Yiddish (the European variant) being predominant.

🔗 Bourbaki dangerous bend symbol

🔗 Mathematics

The dangerous bend or caution symbol ☡ (U+2621 ☡ CAUTION SIGN) was created by the Nicolas Bourbaki group of mathematicians and appears in the margins of mathematics books written by the group. It resembles a road sign that indicates a "dangerous bend" in the road ahead, and is used to mark passages tricky on a first reading or with an especially difficult argument.

Discussed on

🔗 Freedom to Roam

🔗 Environment 🔗 Law 🔗 Backpacking

The freedom to roam, or "everyman's right", is the general public's right to access certain public or privately owned land, lakes, and rivers for recreation and exercise. The right is sometimes called the right of public access to the wilderness or the "right to roam".

In Scotland, Finland, Iceland, Norway, Sweden, Estonia, Latvia, Lithuania, Austria, Czech Republic and Switzerland, the freedom to roam takes the form of general public rights which are sometimes codified in law. The access is ancient in parts of Northern Europe and has been regarded as sufficiently basic that it was not formalised in law until modern times. However, the right usually does not include any substantial economic exploitation, such as hunting or logging, or disruptive activities, such as making fires and driving offroad vehicles.

In England and Wales public access rights apply only to certain categories of mainly uncultivated land.

Discussed on

🔗 Gene Gun

🔗 Genetics 🔗 Molecular Biology/Molecular and Cell Biology

In genetic engineering, a gene gun or biolistic particle delivery system is a device used to deliver exogenous DNA (transgenes), RNA, or protein to cells. By coating particles of a heavy metal with a gene of interest and firing these micro-projectiles into cells using mechanical force, an integration of desired genetic information can be induced into cells. The technique involved with such micro-projectile delivery of DNA is often referred to as biolistics.

This device is able to transform almost any type of cell and is not limited to the transformation of the nucleus; it can also transform organelles, including plastids and mitochondria.

🔗 Alchian–Allen effect

🔗 Economics

The Alchian–Allen effect was described in 1964 by Armen Alchian and William R Allen in the book University Economics (now called Exchange and Production). It states that when the prices of two substitute goods, such as high and low grades of the same product, are both increased by a fixed per-unit amount such as a transportation cost or a lump-sum tax, consumption will shift toward the higher-grade product. This is because the added per-unit amount decreases the relative price of the higher-grade product.

Suppose, for example, that high-grade coffee beans are $3/pound and low-grade beans $1.50/pound; in this example, high-grade beans cost twice as much as low-grade beans. Now add a per-pound international shipping cost of $1. The effective prices are now $4 and $2.50; high-grade beans now cost only 1.6 times as much as low-grade beans. This reduced ratio of difference will induce distant coffee-buyers to now choose a higher ratio of high-to-low grade beans than local coffee-buyers.

The effect has been studied as it applies to illegal drugs and it has been shown that the potency of marijuana increased in response to higher enforcement budgets, and there was a similar effect for alcohol in the U.S. during Prohibition. This effect is called iron law of prohibition.

Another example is that Australians drink higher-quality Californian wine than Californians, and vice versa, because it is only worth the transportation costs for the most expensive wine.

Colloquially, the Alchian–Allen theorem is also known as the “shipping the good apples out” theorem (Thomas Borcherding), or as the “third law of demand.”

Discussed on