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๐Ÿ”— Floral formula

๐Ÿ”— Plants

A floral formula is a notation for representing the structure of particular types of flowers. Such notations use numbers, letters and various symbols to convey significant information in a compact form. They may represent the floral form of a particular species, or may be generalized to characterize higher taxa, usually giving ranges of numbers of organs. Floral formulae are one of the two ways of describing flower structure developed during the 19th century, the other being floral diagrams. The format of floral formulae differs according to the tastes of particular authors and periods, yet they tend to convey the same information.

A floral formula is often used along with a floral diagram.

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๐Ÿ”— Motion Camouflage

๐Ÿ”— Evolutionary biology ๐Ÿ”— Ecology ๐Ÿ”— Project-independent assessment

Motion camouflage is camouflage which provides a degree of concealment for a moving object, given that motion makes objects easy to detect however well their coloration matches their background or breaks up their outlines.

The principal form of motion camouflage, and the type generally meant by the term, involves an attacker's mimicking the optic flow of the background as seen by its target. This enables the attacker to approach the target while appearing to remain stationary from the target's perspective, unlike in classical pursuit (where the attacker moves straight towards the target at all times, and often appears to the target to move sideways). The attacker chooses its flight path so as to remain on the line between the target and some landmark point. The target therefore does not see the attacker move from the landmark point. The only visible evidence that the attacker is moving is its looming, the change in size as the attacker approaches.

Camouflage is sometimes facilitated by motion, as in the leafy sea dragon and some stick insects. These animals complement their passive camouflage by swaying like plants in the wind or ocean currents, delaying their recognition by predators.

First discovered in hoverflies in 1995, motion camouflage by minimizing optic flow has been demonstrated in another insect order, dragonflies, as well as in two groups of vertebrates, falcons and echolocating bats. Since bats hunt at night, they cannot use camouflage. Instead they use an efficient homing strategy called constant absolute target direction. It has been suggested that anti-aircraft missiles could benefit from similar techniques.

๐Ÿ”— Animal Welfare in Nazi Germany

๐Ÿ”— History ๐Ÿ”— Germany ๐Ÿ”— Politics ๐Ÿ”— Austria ๐Ÿ”— European history ๐Ÿ”— Animal rights ๐Ÿ”— Former countries

There was widespread support for animal welfare in Nazi Germany (German: Tierschutz im nationalsozialistischen Deutschland) among the country's leadership. Adolf Hitler and his top officials took a variety of measures to ensure animals were protected.

Several Nazis were environmentalists, and species protection and animal welfare were significant issues in the Nazi regime. Heinrich Himmler made an effort to ban the hunting of animals. Hermann Gรถring was a professed animal lover and conservationist, who, on instructions from Hitler, committed Germans who violated Nazi animal welfare laws to concentration camps. In his private diaries, Nazi Propaganda Minister Joseph Goebbels described Hitler as a vegetarian whose hatred of the Jewish religion in large part stemmed from the ethical distinction this faith drew between the value of humans and the value of other animals; Goebbels also mentions that Hitler planned to ban slaughterhouses in the German Reich following the conclusion of World War II. Nevertheless, animal testing was common in Nazi Germany.

The current animal welfare laws in Germany were initially introduced by the Nazis.

๐Ÿ”— List of music considered the worst

๐Ÿ”— Lists ๐Ÿ”— Songs ๐Ÿ”— Albums

This list consists of albums or songs that have been considered the worst music ever made by various combinations of music critics, television broadcasters (such as MTV), radio stations, composers, and public polls.

Individual tastes can vary widely such that very little consensus can be achieved. For example, the winning song in a CNN email poll received less than 5 percent of the total votes cast.

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๐Ÿ”— Rossum's Universal Robots

๐Ÿ”— Science Fiction ๐Ÿ”— Robotics ๐Ÿ”— Theatre ๐Ÿ”— Czech Republic

R.U.R. is a 1920 science-fiction play by the Czech writer Karel ฤŒapek. "R.U.R." stands for Rossumovi Univerzรกlnรญ Roboti (Rossum's Universal Robots, a phrase that has been used as a subtitle in English versions). The play had its world premiere on 2 January 1921 in Hradec Krรกlovรฉ; it introduced the word "robot" to the English language and to science fiction as a whole. R.U.R. soon became influential after its publication. By 1923 it had been translated into thirty languages. R.U.R. was successful in its time in Europe and North America. ฤŒapek later took a different approach to the same theme in his 1936 novel War with the Newts, in which non-humans become a servant-class in human society.

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๐Ÿ”— Commonplace Book

๐Ÿ”— Literature ๐Ÿ”— Education ๐Ÿ”— Reference works

Commonplace books (or commonplaces) are a way to compile knowledge, usually by writing information into books. They have been kept from antiquity, and were kept particularly during the Renaissance and in the nineteenth century. Such books are essentially scrapbooks filled with items of every kind: recipes, quotes, letters, poems, tables of weights and measures, proverbs, prayers, legal formulas. Commonplaces are used by readers, writers, students, and scholars as an aid for remembering useful concepts or facts. Each one is unique to its creator's particular interests but they almost always include passages found in other texts, sometimes accompanied by the compiler's responses. They became significant in Early Modern Europe.

"Commonplace" is a translation of the Latin term locus communis (from Greek tรณpos koinรณs, see literary topos) which means "a general or common topic", such as a statement of proverbial wisdom. In this original sense, commonplace books were collections of such sayings, such as John Milton's example. Scholars now understand them to include manuscripts in which an individual collects material which have a common theme, such as ethics, or exploring several themes in one volume. Commonplace books are private collections of information, but they are not diaries or travelogues.

In 1685 the English Enlightenment philosopher John Locke wrote a treatise in French on commonplace books, translated into English in 1706 as A New Method of Making Common-Place-Books, "in which techniques for entering proverbs, quotations, ideas, speeches were formulated. Locke gave specific advice on how to arrange material by subject and category, using such key topics as love, politics, or religion. Commonplace books, it must be stressed, are not journals, which are chronological and introspective."

By the early eighteenth century they had become an information management device in which a note-taker stored quotations, observations and definitions. They were used in private households to collate ethical or informative texts, sometimes alongside recipes or medical formulae. For women, who were excluded from formal higher education, the commonplace book could be a repository of intellectual references. The gentlewoman Elizabeth Lyttelton kept one from the 1670s to 1713 and a typical example was published by Mrs Anna Jameson in 1855, including headings such as Ethical Fragments; Theological; Literature and Art. Commonplace books were used by scientists and other thinkers in the same way that a database might now be used: Carl Linnaeus, for instance, used commonplacing techniques to invent and arrange the nomenclature of his Systema Naturae (which is the basis for the system used by scientists today). The commonplace book was often a lifelong habit: for example the English-Australian artist Georgina McCrae kept a commonplace book from 1828-1865.

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๐Ÿ”— Dimetrodon

๐Ÿ”— Palaeontology ๐Ÿ”— Amphibians and Reptiles ๐Ÿ”— Mammals

Dimetrodon ( (listen) or , meaning "two measures of teeth") is an extinct genus of non-mammalian synapsids that lived during the Cisuralian (Early Permian), around 295โ€“272ย million years ago (Ma). It is a member of the family Sphenacodontidae. The most prominent feature of Dimetrodon is the large neural spine sail on its back formed by elongated spines extending from the vertebrae. It walked on four legs and had a tall, curved skull with large teeth of different sizes set along the jaws. Most fossils have been found in the southwestern United States, the majority coming from a geological deposit called the Red Beds of Texas and Oklahoma. More recently, fossils have been found in Germany. Over a dozen species have been named since the genus was first described in 1878.

Dimetrodon is often mistaken for a dinosaur or as a contemporary of dinosaurs in popular culture, but it became extinct some 40ย million years before the first appearance of dinosaurs. Reptile-like in appearance and physiology, Dimetrodon is nevertheless more closely related to mammals than to modern reptiles, though it is not a direct ancestor of mammals. Dimetrodon is assigned to the "non-mammalian synapsids", a group traditionally called "mammal-like reptiles". This groups Dimetrodon together with mammals in a clade (evolutionary group) called Synapsida, while placing dinosaurs, reptiles and birds in a separate clade, Sauropsida. Single openings in the skull behind each eye, known as temporal fenestrae, and other skull features distinguish Dimetrodon and mammals from most of the earliest sauropsids.

Dimetrodon was probably one of the apex predators of the Cisuralian ecosystems, feeding on fish and tetrapods, including reptiles and amphibians. Smaller Dimetrodon species may have had different ecological roles. The sail of Dimetrodon may have been used to stabilize its spine or to heat and cool its body as a form of thermoregulation. Some recent studies argue that the sail would have been ineffective at removing heat from the body due to large species being discovered with small sails and small species being discovered with large sails, essentially ruling out heat regulation as its main purpose. The sail was most likely used in courtship display with methods such as threatening rivals or showing off to potential mates.

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๐Ÿ”— Biefeldโ€“Brown effect

๐Ÿ”— Physics ๐Ÿ”— Alternative Views

The Biefeldโ€“Brown effect is an electrical phenomenon that produces an ionic wind that transfers its momentum to surrounding neutral particles. It describes a force observed on an asymmetric capacitor when high voltage is applied to the capacitor's electrodes. Once suitably charged up to high DC potentials, a thrust at the negative terminal, pushing it away from the positive terminal, is generated. The effect was named by inventor Thomas Townsend Brown who claimed that he did a series of experiments with professor of astronomy Paul Alfred Biefeld, a former teacher of Brown whom Brown claimed was his mentor and co-experimenter at Denison University in Ohio.

The use of an asymmetric capacitor, with the negative electrode being larger than the positive electrode, allowed for more thrust to be produced in the direction from the low-flux to the high-flux region compared to a conventional capacitor. These asymmetric capacitors became known as Asymmetrical Capacitor Thrusters (ACT). The Biefeldโ€“Brown effect can be observed in ionocrafts and lifters, which utilize the effect to produce thrust in the air without requiring any combustion or moving parts.

In his 1960 patent titled "Electrokinetic Apparatus," Brown refers to electrokinesis to describe the Biefeldโ€“Brown effect, linking the phenomenon to the field of electrohydrodynamics (EHD). Brown also believed the Biefeldโ€“Brown effect could produce an anti-gravity force, referred to as "electrogravitics" based on it being an electricity/gravity phenomenon. However, there is little evidence that supports Brown's claim on the effect's anti-gravity properties.

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๐Ÿ”— Gini coefficient

๐Ÿ”— Mathematics ๐Ÿ”— Economics ๐Ÿ”— Statistics ๐Ÿ”— Sociology ๐Ÿ”— Globalization

In economics, the Gini coefficient ( JEE-nee), sometimes called the Gini index or Gini ratio, is a measure of statistical dispersion intended to represent the income or wealth distribution of a nation's residents, and is the most commonly used measurement of inequality. It was developed by the Italian statistician and sociologist Corrado Gini and published in his 1912 paper Variability and Mutability (Italian: Variabilitร  e mutabilitร ).

The Gini coefficient measures the inequality among values of a frequency distribution (for example, levels of income). A Gini coefficient of zero expresses perfect equality, where all values are the same (for example, where everyone has the same income). A Gini coefficient of one (or 100%) expresses maximal inequality among values (e.g., for a large number of people, where only one person has all the income or consumption, and all others have none, the Gini coefficient will be very nearly one). For larger groups, values close to one are very unlikely in practice. Given the normalization of both the cumulative population and the cumulative share of income used to calculate the Gini coefficient, the measure is not overly sensitive to the specifics of the income distribution, but rather only on how incomes vary relative to the other members of a population. The exception to this is in the redistribution of income resulting in a minimum income for all people. When the population is sorted, if their income distribution were to approximate a well-known function, then some representative values could be calculated.

The Gini coefficient was proposed by Gini as a measure of inequality of income or wealth. For OECD countries, in the late 20th century, considering the effect of taxes and transfer payments, the income Gini coefficient ranged between 0.24 and 0.49, with Slovenia being the lowest and Mexico the highest. African countries had the highest pre-tax Gini coefficients in 2008โ€“2009, with South Africa the world's highest, variously estimated to be 0.63 to 0.7, although this figure drops to 0.52 after social assistance is taken into account, and drops again to 0.47 after taxation. The global income Gini coefficient in 2005 has been estimated to be between 0.61 and 0.68 by various sources.

There are some issues in interpreting a Gini coefficient. The same value may result from many different distribution curves. The demographic structure should be taken into account. Countries with an aging population, or with a baby boom, experience an increasing pre-tax Gini coefficient even if real income distribution for working adults remains constant. Scholars have devised over a dozen variants of the Gini coefficient.

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๐Ÿ”— Sony BMG Rootkit Scandal

๐Ÿ”— Computing ๐Ÿ”— Crime ๐Ÿ”— Computer Security ๐Ÿ”— Computer Security/Computing ๐Ÿ”— Business ๐Ÿ”— Computing/Software

A scandal erupted in 2005 regarding Sony BMG's implementation of copy protection measures on about 22 million CDs. When inserted into a computer, the CDs installed one of two pieces of software that provided a form of digital rights management (DRM) by modifying the operating system to interfere with CD copying. Neither program could easily be uninstalled, and they created vulnerabilities that were exploited by unrelated malware. One of the programs would install and "phone home" with reports on the user's private listening habits, even if the user refused its end-user license agreement (EULA), while the other was not mentioned in the EULA at all. Both programs contained code from several pieces of copylefted free software in an apparent infringement of copyright, and configured the operating system to hide the software's existence, leading to both programs being classified as rootkits.

Sony BMG initially denied that the rootkits were harmful. It then released an uninstaller for one of the programs that merely made the program's files visible while also installing additional software that could not be easily removed, collected an email address from the user and introduced further security vulnerabilities.

Following public outcry, government investigations and class-action lawsuits in 2005 and 2006, Sony BMG partially addressed the scandal with consumer settlements, a recall of about 10% of the affected CDs and the suspension of CD copy-protection efforts in early 2007.

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