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🔗 United States/U.S. Government 🔗 United States 🔗 Law 🔗 Open

Patentleft (also patent left, copyleft-style patent license or open patent) is the practice of licensing patents (especially biological patents) for royalty-free use, on the condition that adopters license related improvements they develop under the same terms. Copyleft-style licensors seek "continuous growth of a universally accessible technology commons" from which they, and others, will benefit.

Patentleft is analogous to copyleft, a license which allows distribution of a copyrighted work and derived works, but only under the same or equivalent terms.

🔗 Soviet Union 🔗 Russia 🔗 History 🔗 Germany 🔗 Politics 🔗 Cold War 🔗 European history

The Stalin Note, also known as the March Note, was a document delivered to the representatives of the Western Allies (the United Kingdom, France, and the United States) from the Soviet Union in Germany on 10 March 1952. Soviet general secretary and premier Joseph Stalin put forth a proposal for a German reunification and neutralisation with no conditions on economic policies and with guarantees for "the rights of man and basic freedoms, including freedom of speech, press, religious persuasion, political conviction, and assembly" and free activity of democratic parties and organizations.

James Warburg, a member of the United States Senate Committee on Foreign Relations, testified before the committee on 28 March 1952 and observed that the Soviet proposal might be a bluff, but he thought that it seemed "that our government is afraid to call the bluff for the fear that it may not be a bluff at all" and might lead to "a free, neutral, and demilitarised Germany", which might be "subverted into Soviet orbit". That led to an exchange of notes between the West and the Soviet Union, which eventually ended after the West had insistence for a unified Germany to be free to join the European Defence Community and to be rearmed, demands that Stalin rejected.

West German Chancellor Konrad Adenauer and the Western Allies characterised Stalin's move as an aggressive action that attempted to stall the reintegration of West Germany. However, there was later a debate on whether a chance for reunification had been missed. Six years after the exchange, two West German ministers, Thomas Dehler and Gustav Heinemann, blamed Adenauer for not having explored the chance of reunification.

🔗 Mathematics

The 15-puzzle (also called Gem Puzzle, Boss Puzzle, Game of Fifteen, Mystic Square and many others) is a sliding puzzle that consists of a frame of numbered square tiles in random order with one tile missing. The puzzle also exists in other sizes, particularly the smaller 8-puzzle. If the size is 3×3 tiles, the puzzle is called the 8-puzzle or 9-puzzle, and if 4×4 tiles, the puzzle is called the 15-puzzle or 16-puzzle named, respectively, for the number of tiles and the number of spaces. The object of the puzzle is to place the tiles in order by making sliding moves that use the empty space.

The n-puzzle is a classical problem for modelling algorithms involving heuristics. Commonly used heuristics for this problem include counting the number of misplaced tiles and finding the sum of the taxicab distances between each block and its position in the goal configuration. Note that both are admissible, i.e. they never overestimate the number of moves left, which ensures optimality for certain search algorithms such as A*.

🔗 Physics 🔗 History of Science

The ultraviolet catastrophe, also called the Rayleigh–Jeans catastrophe, was the prediction of late 19th century to early 20th century classical physics that an ideal black body at thermal equilibrium would emit an unbounded quantity of energy as wavelength decreased into the ultraviolet range.^: 6–7 The term "ultraviolet catastrophe" was first used in 1911 by Paul Ehrenfest, but the concept originated with the 1900 statistical derivation of the Rayleigh–Jeans law.

The phrase refers to the fact that the empirically derived Rayleigh–Jeans law, which accurately predicted experimental results at large wavelengths, failed to do so for short wavelengths. (See the image for further elaboration.) As the theory diverged from empirical observations when these frequencies reached the ultraviolet region of the electromagnetic spectrum, there was a problem. This problem was later found to be due to a property of quanta as proposed by Max Planck: There could be no fraction of a discrete energy package already carrying minimal energy.

Since the first use of this term, it has also been used for other predictions of a similar nature, as in quantum electrodynamics and such cases as ultraviolet divergence.

🔗 Australia 🔗 Australia/Western Australia 🔗 Australia/Australian biota 🔗 Spiders

Number 16 (c. 1974 – 2016), also known as #16, was a wild female trapdoor spider (Gaius villosus, family Idiopidae) that lived in North Bungulla Reserve near Tammin, Western Australia. She lived an estimated 43 years and became the longest-lived spider on record, beating a 28-year-old tarantula who previously held the title. When Number 16 finally died in 2016, it was not of old age but from a parasitic wasp sting.

🔗 Songs

"Hitler Has Only Got One Ball", sometimes known as "The River Kwai March", is a World War II British song, the lyrics of which, sung to the tune of the World War I-era "Colonel Bogey March", impugn the masculinity of Nazi leaders by alleging they had missing, deformed, or undersized testicles. Multiple variant lyrics exist, but the most common version refers to rumours that Adolf Hitler had monorchism ("one ball"), and accuses Hermann Göring and Heinrich Himmler of microorchidism ("two but very small") and Joseph Goebbels of anorchia ("no balls at all"). An alternative version suggests Hitler's missing testicle is displayed as a war trophy in the Royal Albert Hall.

The author of the lyrics is unknown, though several claims have been made. The song first appeared among British soldiers in 1939 and was quickly taken up by Allied military and civilians. Its familiarity increased after its use in a scene in the 1957 film The Bridge on the River Kwai. The song has been cited as an example of morally-correct disrespect that used political mockery to boost morale in wartime.

🔗 Computer science

In information theory, linguistics and computer science, the Levenshtein distance is a string metric for measuring the difference between two sequences. Informally, the Levenshtein distance between two words is the minimum number of single-character edits (insertions, deletions or substitutions) required to change one word into the other. It is named after the Soviet mathematician Vladimir Levenshtein, who considered this distance in 1965.

Levenshtein distance may also be referred to as edit distance, although that term may also denote a larger family of distance metrics known collectively as edit distance. It is closely related to pairwise string alignments.

🔗 Economics

Eagle Cash (stylized as EagleCash), and sister program EZpay, are cash management applications that use stored-value card technology to process financial transactions in "closed-loop" operating environments. The United States Department of the Treasury sponsors the programs for the U.S. Armed Forces. The Federal Reserve Bank of Boston administers the programs for the Treasury, and they are in use at approved U.S. military facilities inside and outside the continental United States. The systems use a plastic payment card, similar to a credit or debit card, which has an embedded microchip that tracks the card's balance and interfaces with encrypted card readers. This method allows soldiers to purchase goods and services at U.S. military posts and canteens, without carrying cash, or manage their personal bank accounts while on deployment or in training. The program reduces the amount of American currency required overseas, reduces theft, saves thousands of man-hours in labor, helps reduce the risk of transporting cash in combat environments, and increases security and convenience for service members. It helped reduce or eliminate the need for cash and money orders.

🔗 United States 🔗 International relations 🔗 Disaster management 🔗 Medicine 🔗 Viruses 🔗 Death

The 2009 flu pandemic in the United States was a novel strain of the Influenza A/H1N1 virus, commonly referred to as "swine flu", that began in the spring of 2009. The virus had spread to the US from an outbreak in Mexico.

The U.S. Centers for Disease Control and Prevention (CDC) estimates that from April 12, 2009 to April 10, 2010, there were 60.8 million cases, 274,000 hospitalizations, and 12,469 deaths (0.02% infection fatality rate/Mortality rate) in the United States due to the virus.

🔗 California 🔗 California/San Francisco Bay Area 🔗 Education 🔗 Museums

The Exploratorium is a museum of science, technology, and arts in San Francisco. Its mission is to create inquiry-based experiences that transform learning worldwide. It has been described by the New York Times as the most important science museum to have opened since the mid-20th century, an achievement attributed to "the nature of its exhibits, its wide-ranging influence and its sophisticated teacher training program". Characterized as "a mad scientist's penny arcade, a scientific funhouse, and an experimental laboratory all rolled into one", the participatory nature of its exhibits and its self-identification as a center for informal learning has led to it being cited as the prototype for participatory museums around the world.

The Exploratorium was founded by physicist and educator Frank Oppenheimer and opened in 1969 at the Palace of Fine Arts, its home until January 2, 2013. On April 17, 2013, the Exploratorium reopened at Piers 15 and 17 on San Francisco's Embarcadero. The historic interior and exterior of Pier 15 was renovated extensively prior to the move, and is divided into several galleries mainly separated by content, including the physics of seeing and listening (Light and Sound), Human Behavior, Living Systems, Tinkering (including electricity and magnetism), the Outdoor Gallery, and the Bay Observatory Gallery, which focuses on local environment, weather, and landscape.

Since the museum's founding, over 1,000 participatory exhibits have been created, approximately 600 of which are on the floor at any given time. The exhibit-building workshop space is contained within the museum and is open to view. In addition to the public exhibition space, the Exploratorium has been engaged in the professional development of teachers, science education reform, and the promotion of museums as informal education centers since its founding. Since Oppenheimer's death in 1985, the Exploratorium has expanded into other domains, including its 50,000-page website and two iPad apps on sound and color. It has also inspired an international network of participatory museums working to engage the public with general science education. The new Exploratorium building is also working to showcase environmental sustainability efforts as part of its goal to become the largest net-zero museum in the country.

The Exploratorium offers visitors a variety of ways—including exhibits, webcasts, websites and events—for visitors to explore and understand the world around them. In 2011, the Exploratorium received the National Science Board 2011 Public Service Science Award for its contributions to public understanding of science and engineering.