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🔗 Operation Serenata de Amor – An AI project to analyze public spending in Brazil
Operation Serenata de Amor is an artificial intelligence project to analyze public spending in Brazil. The project has been funded by a recurrent financing campaign since September 7, 2016, and came in the wake of major scandals of misappropriation of public funds in Brazil, such as the Mensalão scandal and what was revealed in the Operation Car Wash investigations.
The analysis began with data from the National Congress and then expanded to other types of budget and other instances of government, such as the Federal Senate. The project is built through collaboration on GitHub and using a public group with more than 600 participants on Telegram.
The name "Serenata de Amor," which means "serenade of love," was taken from a popular cashew cream bonbon produced by Chocolates Garoto in Brazil.
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- "Operation Serenata de Amor – An AI project to analyze public spending in Brazil" | 2018-03-06 | 342 Upvotes 110 Comments
🔗 B. Traven
B. Traven (German: [ˈbeː ˈtʁaːvn̩]; Bruno Traven in some accounts) was the pen name of a presumably German novelist, whose real name, nationality, date and place of birth and details of biography are all subject to dispute. One of the few certainties about Traven's life is that he lived for years in Mexico, where the majority of his fiction is also set—including The Treasure of the Sierra Madre (1927). The film adaptation of the same name won three Academy Awards in 1948.
Virtually every detail of Traven's life has been disputed and hotly debated. There were many hypotheses on the true identity of B. Traven, some of them wildly fantastic. The person most commonly identified as Traven is Ret Marut, a German stage actor and anarchist who supposedly left Europe for Mexico around 1924 and who had edited an anarchist newspaper in Germany called Der Ziegelbrenner (The Brick Burner). Marut is thought to have operated under the "B. Traven" pseudonym, although no details are known about Marut's life before 1912, and many hold that "Ret Marut" was in fact also a pseudonym.
Some researchers further argue that Marut/Traven's original name was Otto Feige and that he was born in Schwiebus in Brandenburg, modern-day Świebodzin in Poland. This theory is not universally accepted. B. Traven in Mexico is also connected with the names of Berick Traven Torsvan and Hal Croves, both of whom appeared and acted in different periods of the writer's life. Both, however, denied being Traven and claimed that they were his literary agents only, representing him in contacts with his publishers.
B. Traven is the author of twelve novels, one book of reportage and several short stories, in which the sensational and adventure subjects combine with a critical attitude towards capitalism. B. Traven's best known works include the novels The Death Ship from 1926, The Treasure of the Sierra Madre from 1927 (filmed in 1948 by John Huston), and the so-called "Jungle Novels", also known as the Caoba cyclus (from the Spanish word caoba, meaning mahogany). The Jungle Novels are a group of six novels (including The Carreta and Government), published in the years 1930–1939 and set among Mexican Indians just before and during the Mexican Revolution in the early 20th century. B. Traven's novels and short stories became very popular as early as the interwar period and retained this popularity after the Second World War; they were also translated into many languages. Most of B. Traven's books were published in German first, with their English editions appearing later; nevertheless, the author always claimed that the English versions were the original ones and that the German versions were only their translations. This claim is mostly treated by Traven scholars as a diversion or a joke, although there are those who accept it.
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- "B. Traven" | 2021-04-17 | 107 Upvotes 36 Comments
🔗 Hybridogenesis in water frogs
The fertile hybrids of European water frogs (genus Pelophylax) reproduce by hybridogenesis (hemiclonally). This means that during gametogenesis, they discard the genome of one of the parental species and produce gametes of the other parental species (containing a genome not recombined with the genome of the first parental species). The first parental genome is restored by fertilization of these gametes with gametes from the first species (sexual host). In all-hybrid populations of the edible frog Pelophylax kl. esculentus, however, triploid hybrids provide this missing genome.
Because half of the genome is transmitted to the next generation clonally (not excluded unrecombined intact genome), and only the other half sexually (recombined genome of the sexual host), the hybridogenesis is a hemiclonal mode of reproduction.
For example, the edible frog Pelophylax kl. esculentus (mostly RL genome), which is a hybridogenetic hybrid of the marsh frog P. ridibundus (RR) and the pool frog P. lessonae (LL), usually excludes the lessonae genome (L) and generates gametes of the P. ridibundus (R). In other words, edible frogs produce gametes of marsh frogs.
The hybrid populations are propagated, however, not by the above primary hybridisations, but predominantly by backcrosses with one of the parental species they coexist (live in sympatry) with (see below in the middle).
Since the hybridogenetic hybrids require another taxon as sexual host to reproduce, usually one of the parental species, they are called kleptons (with "kl." in scientific names).
There are three known hybridogenetic hybrids of the European water frogs:
- edible frog Pelophylax kl. esculentus (usually genotype RL):
pool frog P. lessonae (LL) × P. ridibundus (RR) - Graf's hybrid frog Pelophylax kl. grafi (PR):
Perez's frog P. perezi (PP) × P. ridibundus (RR) or
Perez's frog P. perezi (PP) × edible frog P. kl. esculentus (RE)
(it is unclear which one crossing was the primary hybridisation) - Italian edible frog Pelophylax kl. hispanicus (RB):
Italian pool frog P. bergeri (BB) × P. ridibundus (RR)
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- "Hybridogenesis in water frogs" | 2019-05-26 | 21 Upvotes 1 Comments
🔗 Anne Morelli: The Basic Principles of War Propaganda
The basic principles of war propaganda (Principes élémentaires de propagande de guerre) is a monograph by Anne Morelli published in 2001. It has not been translated into English. The subtitle recommends its "usability in case of cold war, hot war and lukewarm war" (Utilisables en cas de guerre froide, chaude ou tiède).
The ten "commandments" of propaganda which Anne Morelli elaborates in this work are, above all, an analytical framework for pedagogical purposes and for media analysis. Morelli does not want to take sides or defend "dictators", but show the regularity of use of the ten principles in the media and in society:
- "I will not put to test the purity of one or the other's intentions. I am not going to find out who is lying and who is telling the truth, who is believing what he says, and who does not. My only intention is to illustrate the principles of propaganda that are used and to describe their functioning." (P. 6)
Nonetheless, it seems undeniable to the author that after the wars that characterize our epoch (Kosovo, Second Gulf War, Afghanistan War, Iraq War), Western democracies and their media must be discussed.
As Rudolph Walter in his review in Die Zeit shows, Morelli in this work adapts the typical forms of various contents of propaganda to news of her time. She takes up Arthur Ponsonby's Falsehood in War-Time and George Demartial's La mobilisation des consciences. La guerre de 1914 about propaganda in the First World War, systematizes them in the form of ten principles, and applies them to both world wars, the war in the Balkan, and the war in Afghanistan. Four of the following principles, according to Walter just emanate directly from the principle of friend or foe, "we and them" mindset and simplistic thinking in terms of black and white.
🔗 Shortt–Synchronome free pendulum clock
The Shortt–Synchronome free pendulum clock was a complex precision electromechanical pendulum clock invented in 1921 by British railway engineer William Hamilton Shortt in collaboration with horologist Frank Hope-Jones, and manufactured by the Synchronome Co., Ltd. of London, UK. They were the most accurate pendulum clocks ever commercially produced, and became the highest standard for timekeeping between the 1920s and the 1940s, after which mechanical clocks were superseded by quartz time standards. They were used worldwide in astronomical observatories, naval observatories, in scientific research, and as a primary standard for national time dissemination services. The Shortt was the first clock to be a more accurate timekeeper than the Earth itself; it was used in 1926 to detect tiny seasonal changes in the Earth's rotation rate. Shortt clocks achieved accuracy of around a second per year, although a recent measurement indicated they were even more accurate. About 100 were produced between 1922 and 1956.
Shortt clocks kept time with two pendulums, a master pendulum swinging in a vacuum tank and a slave pendulum in a separate clock, which was synchronized to the master by an electric circuit and electromagnets. The slave pendulum was attached to the timekeeping mechanisms of the clock, leaving the master pendulum virtually free of external disturbances.
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- "Shortt–Synchronome free pendulum clock" | 2020-09-17 | 62 Upvotes 18 Comments
🔗 Ōmoto
Oomoto (大本, Ōmoto, Great Source, or Great Origin), also known as Oomoto-kyo (大本教, Ōmoto-kyō), is a religion founded in 1892 by Deguchi Nao (1836–1918), often categorised as a new Japanese religion originated from Shinto. The spiritual leaders of the movement have predominantly been women; however, Deguchi Onisaburō (1871–1948) has been considered an important figure in Omoto as a seishi (spiritual teacher). Since 2001, the movement has been guided by its fifth leader, Kurenai Deguchi.
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- "Ōmoto" | 2018-02-05 | 47 Upvotes 4 Comments
🔗 Crinkle Crankle Wall
A crinkle crankle wall, also known as a crinkum crankum, serpentine, ribbon or wavy wall, is an unusual type of garden wall built in a serpentine pattern with alternating curves.
The crinkle crankle wall economizes on bricks, despite its sinuous configuration, because it can be made just one brick thin. If a wall this thin were to be made in a straight line, without buttresses, it would easily topple over. The alternate convex and concave curves in the wall provide stability and help it to resist lateral forces.
"Crinkle crankle" is an ablaut reduplication, defined as something with bends and turns, first attested in 1598 (though "crinkle" and "crankle" have somewhat longer histories). However, it was not until the 18th century that the term began to be applied to wavy walls. At that time these garden walls were usually aligned east-west, so that one side faced south to catch the warming sun and were historically used for growing fruit.
Many crinkle crankle walls are found in the East Anglia region of England where the marshes of The Fens were drained by Dutch engineers starting in the mid-1600s. The walls' construction is attributed to these engineers who called them slangenmuur, meaning snake wall. The county of Suffolk claims at least 50 examples, twice as many as in the whole of the rest of the country, and where crinkle crankle is said to derive from a local dialect. In the estate village of Easton the noted crinkle crankle wall running from the former manor house to All Saints' Church is supposed to be the longest existing example. In Lymington, Hampshire, there are at least two examples of crinkle crankle walls. The oldest is thought to have been constructed at the time of the Napoleonic Wars (1803–1815) by exiled Hanoverian soldiers living in the adjacent house.
As a minor part of a larger system of fortification, such a wall may have been used to force oncoming troops to break ranks from closed to open ranks, and further expose them to defensive assault.
Thomas Jefferson (1743–1826) incorporated so-called serpentine walls into the architecture of the University of Virginia, which he founded. Flanking both sides of its landmark rotunda and extending down the length of the lawn are ten pavilions, each with its own walled garden separated by crinkle crankle walls. Although some authorities claim Jefferson invented this design, he was merely adapting a well-established English style of construction. A university document in his own hand shows how he calculated the savings and combined aesthetics with utility.
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- "Crinkle Crankle Wall" | 2019-11-16 | 214 Upvotes 56 Comments
🔗 Bernoulli number
In mathematics, the Bernoulli numbers Bn are a sequence of rational numbers which occur frequently in number theory. The Bernoulli numbers appear in (and can be defined by) the Taylor series expansions of the tangent and hyperbolic tangent functions, in Faulhaber's formula for the sum of m-th powers of the first n positive integers, in the Euler–Maclaurin formula, and in expressions for certain values of the Riemann zeta function.
The values of the first 20 Bernoulli numbers are given in the adjacent table. Two conventions are used in the literature, denoted here by and ; they differ only for n = 1, where and . For every odd n > 1, Bn = 0. For every even n > 0, Bn is negative if n is divisible by 4 and positive otherwise. The Bernoulli numbers are special values of the Bernoulli polynomials , with and (Weisstein 2016).
The Bernoulli numbers were discovered around the same time by the Swiss mathematician Jacob Bernoulli, after whom they are named, and independently by Japanese mathematician Seki Kōwa. Seki's discovery was posthumously published in 1712 (Selin 1997, p. 891; Smith & Mikami 1914, p. 108) in his work Katsuyo Sampo; Bernoulli's, also posthumously, in his Ars Conjectandi of 1713. Ada Lovelace's note G on the Analytical Engine from 1842 describes an algorithm for generating Bernoulli numbers with Babbage's machine (Menabrea 1842, Note G). As a result, the Bernoulli numbers have the distinction of being the subject of the first published complex computer program.
🔗 Photon Sieve
A photon sieve is a device for focusing light using diffraction and interference. It consists of a flat sheet of material full of pinholes that are arranged in a pattern which is similar to the rings in a Fresnel zone plate, but a sieve brings light to much sharper focus than a zone plate. The sieve concept, first developed in 2001, is versatile because the characteristics of the focusing behaviour can be altered to suit the application by manufacturing a sieve containing holes of several different sizes and different arrangement of the pattern of holes.
Photon sieves have applications to photolithography. and are an alternative to lenses or mirrors in telescopes and terahertz lenses and antennas.
When the size of sieves is smaller than one wavelength of operating light, the traditional method mentioned above to describe the diffraction patterns is not valid. The vectorial theory must be used to approximate the diffraction of light from nanosieves. In this theory, the combination of coupled-mode theory and multiple expansion method is used to give an analytical model, which can facilitate the demonstration of traditional devices such as lenses and holograms.
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- "Photon Sieve" | 2022-04-25 | 11 Upvotes 1 Comments
🔗 Friendship Paradox
The friendship paradox is the phenomenon first observed by the sociologist Scott L. Feld in 1991 that most people have fewer friends than their friends have, on average. It can be explained as a form of sampling bias in which people with greater numbers of friends have an increased likelihood of being observed among one's own friends. In contradiction to this, most people believe that they have more friends than their friends have.
The same observation can be applied more generally to social networks defined by other relations than friendship: for instance, most people's sexual partners have had (on the average) a greater number of sexual partners than they have.
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- "The Friendship Paradox" | 2021-07-04 | 27 Upvotes 4 Comments
- "Friendship Paradox" | 2014-08-04 | 288 Upvotes 69 Comments
- "The Friendship Paradox: Why People's Friends Have More Friends Than They Do" | 2010-04-12 | 41 Upvotes 15 Comments