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🔗 Role-playing games

Tunnels & Trolls (abbreviated T&T) is a fantasy role-playing game designed by Ken St. Andre and first published in 1975 by Flying Buffalo. The second modern role-playing game published, it was written by Ken St. Andre to be a more accessible alternative to Dungeons & Dragons and is suitable for solitaire, group, and play-by-mail gameplay.

🔗 Russia 🔗 Physics 🔗 Physics/relativity 🔗 Russia/science and education in Russia

The Novikov self-consistency principle, also known as the Novikov self-consistency conjecture and Larry Niven's law of conservation of history, is a principle developed by Russian physicist Igor Dmitriyevich Novikov in the mid-1980s. Novikov intended it to solve the problem of paradoxes in time travel, which is theoretically permitted in certain solutions of general relativity that contain what are known as closed timelike curves. The principle asserts that if an event exists that would cause a paradox or any "change" to the past whatsoever, then the probability of that event is zero. It would thus be impossible to create time paradoxes.

🔗 United States 🔗 Numismatics 🔗 Numismatics/American currency 🔗 United States/Massachusetts

BerkShares is a local currency that circulates in The Berkshires region of Massachusetts. It was launched on September 29, 2006 by BerkShares Inc., with research and development assistance from the Schumacher Center for a New Economics. The BerkShares website lists around 400 businesses in Berkshire County that accept the currency. Since launch, over 10 million BerkShares have been issued from participating branch offices of local banks (as of February 2020, 9 branches of 3 different banks). The bills were designed by John Isaacs and were printed by Excelsior Printing on special paper with incorporated security features from Crane & Co.. BerkShares are pegged with an exchange rate to the US dollar, but the Schumacher Center has discussed the possibility of pegging its value to a basket of local goods in order to insulate the local economy against volatility in the US economy.

🔗 Philosophy 🔗 Philosophy/Logic 🔗 Philosophy/Metaphysics

Dialetheism (from Greek δι- di- 'twice' and ἀλήθεια alḗtheia 'truth') is the view that there are statements that are both true and false. More precisely, it is the belief that there can be a true statement whose negation is also true. Such statements are called "true contradictions", dialetheia, or nondualisms.

Dialetheism is not a system of formal logic; instead, it is a thesis about truth that influences the construction of a formal logic, often based on pre-existing systems. Introducing dialetheism has various consequences, depending on the theory into which it is introduced. A common mistake resulting from this is to reject dialetheism on the basis that, in traditional systems of logic (e.g., classical logic and intuitionistic logic), every statement becomes a theorem if a contradiction is true, trivialising such systems when dialetheism is included as an axiom. Other logical systems, however, do not explode in this manner when contradictions are introduced; such contradiction-tolerant systems are known as paraconsistent logics. Dialetheists who do not want to allow that every statement is true are free to favour these over traditional, explosive logics.

Graham Priest defines dialetheism as the view that there are true contradictions. Jc Beall is another advocate; his position differs from Priest's in advocating constructive (methodological) deflationism regarding the truth predicate.

🔗 Microbiology

Cable bacteria are filamentous bacteria that conduct electricity across distances over 1 cm in sediment and groundwater aquifers. Cable bacteria allow for long distance electron transport, which connects electron donors to electron acceptors, connecting previously separated oxidation and reduction reactions. Cable bacteria couple the reduction of oxygen or nitrate at the sediment's surface to the oxidation of sulfide in the deeper, anoxic, sediment layers.

🔗 United States 🔗 Companies 🔗 United States/Washington - Seattle 🔗 United States/Washington 🔗 Fashion

Nordstrom, Inc. () is an American luxury department store chain founded in 1901 by John W. Nordstrom and Carl F. Wallin. It originated as a shoe store, and evolved into a full-line retailer with departments for clothing, footwear, handbags, jewelry, accessories, cosmetics, and fragrances. Some stores feature home furnishings and wedding departments, and several have in-house cafes, restaurants, and espresso bars.

As of 2020, Nordstrom operates 117 stores in 40 U.S. states, three Canadian provinces, and Puerto Rico. The corporate headquarters and flagship store are located in the former Frederick & Nelson building in Seattle, Washington; a second flagship store is located near Columbus Circle in New York City. Its subsidiaries include the off-price department store chain Nordstrom Rack and the members-only online store HauteLook.

The cryotron is a switch that operates using superconductivity. The cryotron works on the principle that magnetic fields destroy superconductivity. This simple device consists of two superconducting wires (e.g. tantalum and niobium) with different critical temperature (Tc). The cryotron was invented by Dudley Allen Buck of the Massachusetts Institute of Technology Lincoln Laboratory.

As described by Buck, a straight wire of tantalum (having lower Tc) is wrapped around with a wire of niobium in a single layer coil. Both wires are electrically isolated from each other. When this device is immersed in a liquid helium bath both wires become superconducting and hence offer no resistance to the passage of electric current. Tantalum in superconducting state can carry large amount of current as compared to its normal state. Now when current is passed through the niobium coil (wrapped around tantalum) it produces a magnetic field, which in turn reduces (kills) the superconductivity of the tantalum wire and hence reduces the amount of the current that can flow through the tantalum wire. Hence one can control the amount of the current that can flow in the straight wire with the help of small current in the coiled wire. We can think of the tantalum straight wire as a "gate" and the coiled niobium as a "control".

The article by Buck includes descriptions of several logic circuits implemented using cryotrons, including: one stage of a binary adder, carry network, binary accumulator stage, and two stages of a cryotron stepping register.

A planar cryotron using thin films of lead and tin was developed in 1957 by John Bremer at General Electric's General Engineering Lab in Schenectady, New York. This was one of the first integrated circuits, although using superconductors rather than semiconductors. In the next few years, a demonstration computer was made and arrays with 2000 devices operated. A short history of this work is in the November 2007 newsletter of the IEEE History Center.

Juri Matisoo developed a version of the cryotron incorporating a Josephson junction switched by the magnetic field from a control wire. He also explained the shortcomings of traditional cryotrons in which the superconductive material must transition between superconducting and normal states to switch the device, and thus switch relatively slowly. Matisoo's cryotron switched between a conducting state in which 'pair tunneling' of electrons through the gate took place and a 'resistive' state where only single electrons were able to tunnel. The circuit was (like the traditional cryotron) capable of some amplification (i.e gain greater than unity) had a switching rate of less than 800 picoseconds. Although the requirement for cryogenic cooling limited its practicality, it wasn't until the late 2010s that commercial transistors came close to matching this performance.

There have been periods of renewed interest in various types of cryotron, IBM experimented with using them for limited applications in supercomputers during the 1980s and (as of 2020) there has been some investigation of their potential applications both to I/O and logic in prototype quantum computers.

🔗 North America

The Alcoa 50,000 ton forging press is a heavy press operated at Howmet Aerospace's Cleveland Operations. It was built as part of the Heavy Press Program by the United States Air Force. It was manufactured by Mesta Machinery of West Homestead, Pennsylvania, and began operation on May 5, 1955.

Alcoa ran the plant from the time of its construction, and purchased it outright in 1982. In 2008, cracks were discovered in the press, which had to be shut down for safety reasons. Repairs, originally estimated at a cost of $68 million (equivalent to $81.04 million in 2019), cost a total of $100 million, and were completed in early 2012.

🔗 Color

YInMn Blue (for yttrium, indium, manganese), also known as Oregon Blue, Mas Blue, or Yin Min Blue, is an inorganic blue pigment that was discovered accidentally by Professor Mas Subramanian and his then-graduate student Andrew E. Smith at Oregon State University in 2009. It is the first inorganic blue pigment discovered in 200 years, since cobalt blue was identified in 1802.

The compound has a unique trigonal bipyramidal structure, and further research has discovered it may be modified to create green, purple, and orange pigments.

🔗 United States/U.S. Government 🔗 United States 🔗 International relations 🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Terrorism 🔗 Military history/Cold War 🔗 Cold War 🔗 Military history/South American military history 🔗 Cuba

Operation Northwoods was a proposed false flag operation against the Cuban government that originated within the U.S. Department of Defense (DoD) and the Joint Chiefs of Staff (JCS) of the United States government in 1962. The proposals called for the Central Intelligence Agency (CIA) or other U.S. government operatives to both stage and actually commit acts of terrorism against American military and civilian targets, blaming them on the Cuban government, and using it to justify a war against Cuba. The possibilities detailed in the document included the possible assassination of Cuban immigrants, sinking boats of Cuban refugees on the high seas, hijacking planes to be shot down or given the appearance of being shot down, blowing up a U.S. ship, and orchestrating violent terrorism in U.S. cities. The proposals were rejected by President John F. Kennedy.

Communists led by Fidel Castro had taken power in Cuba in 1959, which aroused the concern of the U.S. military due to the Cold War. The operation proposed creating public support for a war against Cuba by blaming it for terrorist acts that would actually be perpetrated by the U.S. Government. To this end, Operation Northwoods proposals recommended hijackings and bombings followed by the introduction of phony evidence that would implicate the Cuban government. It stated:

The desired result from the execution of this plan would be to place the United States in the apparent position of suffering defensible grievances from a rash and irresponsible government of Cuba and to develop an international image of a Cuban threat to peace in the Western Hemisphere.

Several other proposals were included within Operation Northwoods, including real or simulated actions against various U.S. military and civilian targets. The operation recommended developing a "Communist Cuban terror campaign in the Miami area, in other Florida cities and even in Washington".

The plan was drafted by the Joint Chiefs of Staff, signed by Chairman Lyman Lemnitzer and sent to the Secretary of Defense. Although part of the U.S. government's anti-communist Cuban Project, Operation Northwoods was never officially accepted; it was authorized by the Joint Chiefs of Staff, but then rejected by President John F. Kennedy. According to currently released documentation, none of the operations became active under the auspices of the Operation Northwoods proposals.