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🔗 United States 🔗 Numismatics 🔗 Numismatics/American currency 🔗 U.S. Congress

The United States Gold Reserve Act of January 30, 1934 required that all gold and gold certificates held by the Federal Reserve be surrendered and vested in the sole title of the United States Department of the Treasury. It also prohibited the Treasury and financial institutions from redeeming dollar bills for gold, established the Exchange Stabilization Fund under control of the Treasury to control the dollar’s value without the assistance (or approval) of the Federal Reserve, and authorized the president to establish the gold value of the dollar by proclamation.

Immediately following passage of the Act, the President, Franklin D. Roosevelt, changed the statutory price of gold from $20.67 per troy ounce to $35. This price change incentivized gold miners globally to expand production and foreigners to export their gold to the United States, while simultaneously devaluing the U.S. dollar by increasing inflation. The increase in gold reserves due to the price change resulted in a large accumulation of gold in the Federal Reserve and U.S. Treasury, much of which was stored in the United States Bullion Depository at Fort Knox and other locations. The increase in gold reserves increased the money supply, lowering real interest rates which in turn increased investment in durable goods.

A year earlier, in 1933, Executive Order 6102 had made it a criminal offense for U.S. citizens to own or trade gold anywhere in the world, with exceptions for some jewelry and collector's coins. These prohibitions were relaxed starting in 1964 – gold certificates were again allowed for private investors on April 24, 1964, although the obligation to pay the certificate holder on demand in gold specie would not be honored. By 1975 Americans could again freely own and trade gold.

🔗 Languages 🔗 Deaf 🔗 Nicaragua

Nicaraguan Sign Language (ISN; Spanish: Idioma de Señas de Nicaragua) is a sign language that was largely spontaneously developed by deaf children in a number of schools in western Nicaragua in the 1970s and 1980s. It is of particular interest to the linguists who study it because it offers a unique opportunity to study what they believe to be the birth of a new language.

🔗 Philosophy 🔗 Philosophy/Logic 🔗 Linguistics 🔗 Philosophy/Philosophy of language 🔗 Linguistics/Philosophy of language

Colorless green ideas sleep furiously is a sentence composed by Noam Chomsky in his 1957 book Syntactic Structures as an example of a sentence that is grammatically correct, but semantically nonsensical. The sentence was originally used in his 1955 thesis The Logical Structure of Linguistic Theory and in his 1956 paper "Three Models for the Description of Language". Although the sentence is grammatically correct, no obvious understandable meaning can be derived from it, and thus it demonstrates the distinction between syntax and semantics. As an example of a category mistake, it was used to show the inadequacy of certain probabilistic models of grammar, and the need for more structured models.

🔗 Computer science

The man or boy test was proposed by computer scientist Donald Knuth as a means of evaluating implementations of the ALGOL 60 programming language. The aim of the test was to distinguish compilers that correctly implemented "recursion and non-local references" from those that did not.

There are quite a few ALGOL60 translators in existence which have been designed to handle recursion and non-local references properly, and I thought perhaps a little test-program may be of value. Hence I have written the following simple routine, which may separate the man-compilers from the boy-compilers.

🔗 Telecommunications

The Better Approach to Mobile Ad-hoc Networking (B.A.T.M.A.N.) is a routing protocol for multi-hop mobile ad hoc networks which is under development by the German "Freifunk" community and intended to replace the Optimized Link State Routing Protocol (OLSR).

B.A.T.M.A.N.'s crucial point is the decentralization of knowledge about the best route through the network — no single node has all the data. This technique eliminates the need to spread information about network changes to every node in the network. The individual node only saves information about the "direction" it received data from and sends its data accordingly. The data gets passed from node to node, and packets get individual, dynamically created routes. A network of collective intelligence is created.

In early 2007, the B.A.T.M.A.N. developers started experimenting with the idea of routing on layer 2 (Ethernet layer) instead of layer 3. To differentiate from the layer 3 routing daemon, the suffix "adv" (for: advanced) was chosen. Instead of manipulating routing tables based on information exchanged via UDP/IP, it provides a virtual network interface and transparently transports Ethernet packets on its own. The batman-adv kernel module has been part of the official Linux kernel since 2.6.38.

🔗 Physics

Separation of isotopes by laser excitation (SILEX) is a process for isotope separation that is being investigated to produce enriched uranium on an industrial scale using lasers. It was developed in the 1990s and is a variant of molecular laser isotope separation (MLIS). For uranium, it uses a cold molecular beam with UF₆ in a carrier cas, in which the ²³⁵UF₆ is selectively excited by an infrared laser near 16 µm. But in contrast to earlier MLIS techniques developed since the 1970s, it does not dissociate the molecule.

🔗 Canada 🔗 Appalachia 🔗 Canada/British Columbia

Anvil firing (also known as anvil launching or anvil shooting) is the practice of firing an anvil into the air with gunpowder.

In the UK, the term refers to a method of testing anvils. Black powder was poured onto the top of the anvil and ignited. If the anvil did not shatter it was deemed safe to use.

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Some of the many ways to read Wikipedia while offline:

• Kiwix: (§ Kiwix) – index of images (2024)
• XOWA: (§ XOWA) – index of images (2015)
• WikiTaxi: § WikiTaxi (for Windows)
• aarddict: § Aard Dictionary / Aard 2
• BzReader: § BzReader and MzReader (for Windows)
• WikiFilter: § WikiFilter
• Wikipedia on rockbox: § Wikiviewer for Rockbox
• Selected Wikipedia articles as a printed document: Help:Printing

Some of them are mobile applications – see "List of Wikipedia mobile applications".

🔗 Medicine 🔗 Psychology

Posttraumatic Embitterment Disorder (PTED) is defined as a pathological reaction to a negative life event, which those affected experienced as a grave insult, humiliation, betrayal, or injustice. Prevalent emotions of PTED are embitterment, anger, fury, and hatred, especially against the triggering stressor, often accompanied by fantasies of revenge. The disorder commences immediately and without time delay at the moment of the triggering event. If left untreated, the prognosis of PTED presents as rather unfavorable, since patients find themselves trapped in a vicious circle of strong negative emotions constantly intensifying one another and eventually leading into a self-destructive downward spiral. People affected by PTED are more likely to put fantasies of revenge into action, making them a serious threat to the stressor.

The concept of PTED as a distinct clinical disorder has been first described by the German psychiatrist and psychologist Michael Linden in 2003, who remains its most involved researcher. Even though it has been backed up by empirical research in the past years, it remains disputed as to whether embitterment should be included among psychological disorders. Therefore, PTED currently does not hold its own category in the ICD-10 but is categorized under F43.8 “Other reactions to severe stress”. It cannot be categorized as an adjustment disorder under F43.2, since “ordinary” adjustment disorders normally subside within six months, while PTED is much more likely to become chronical and last for much longer. A condition similar to PTED has already been described by Emil Kraepelin as early as 1915 by the name querulous paranoia as a form of traumatic neuroses, explicitly demarcating it from personality disorders.

🔗 Mathematics

Legendre's constant is a mathematical constant occurring in a formula conjectured by Adrien-Marie Legendre to capture the asymptotic behavior of the prime-counting function ${\displaystyle \pi (x)}$. Its value is now known to be exactly 1.

Examination of available numerical evidence for known primes led Legendre to suspect that ${\displaystyle \pi (x)}$ satisfies an approximate formula.

Legendre conjectured in 1808 that

${\displaystyle \pi (x)={\frac {x}{\ln(x)-B(x)}}}$

where ${\displaystyle \lim _{x\to \infty }B(x)=1.08366}$....OEIS: A228211

Or similarly,

${\displaystyle \lim _{n\to \infty }\left(\ln(n)-{n \over \pi (n)}\right)=B}$

where B is Legendre's constant. He guessed B to be about 1.08366, but regardless of its exact value, the existence of B implies the prime number theorem.

Pafnuty Chebyshev proved in 1849 that if the limit B exists, it must be equal to 1. An easier proof was given by Pintz in 1980.

It is an immediate consequence of the prime number theorem, under the precise form with an explicit estimate of the error term

${\displaystyle \pi (x)={\rm {Li}}(x)+O\left(xe^{-a{\sqrt {\ln x}}}\right)\quad {\text{as }}x\to \infty }$

(for some positive constant a, where O(…) is the big O notation), as proved in 1899 by Charles de La Vallée Poussin, that B indeed is equal to 1. (The prime number theorem had been proved in 1896, independently by Jacques Hadamard and La Vallée Poussin, but without any estimate of the involved error term).

Being evaluated to such a simple number has made the term Legendre's constant mostly only of historical value, with it often (technically incorrectly) being used to refer to Legendre's first guess 1.08366... instead.

Pierre Dusart proved in 2010

${\displaystyle {\frac {x}{\ln x-1}}<\pi (x)}$ for ${\displaystyle x\geq 5393}$, and

${\displaystyle \pi (x)<{\frac {x}{\ln x-1.1}}}$ for ${\displaystyle x\geq 60184}$. This is of the same form as

${\displaystyle \pi (x)={\frac {x}{\ln(x)-B(x)}}}$ with ${\displaystyle 1<B(x)<1.1}$.