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Kellogg–Briand Pact
The Kellogg–Briand Pact or Pact of Paris – officially the General Treaty for Renunciation of War as an Instrument of National Policy – is a 1928 international agreement on peace in which signatory states promised not to use war to resolve "disputes or conflicts of whatever nature or of whatever origin they may be, which may arise among them". The pact was signed by Germany, France, and the United States on 27 August 1928, and by most other states soon after. Sponsored by France and the U.S., the Pact is named after its authors, United States Secretary of State Frank B. Kellogg and French foreign minister Aristide Briand. The pact was concluded outside the League of Nations and remains in effect. A common criticism is that the Kellogg–Briand Pact did not live up to all of its aims, but it has arguably had some success. It was unable to prevent the Second World War, but it was the base for trial and execution of Nazi leaders in 1946. Furthermore declared wars became very rare after 1945. However, it has also been ridiculed for its moralism, legalism and lack of influence on foreign policy. The pact had no mechanism for enforcement, and many historians and political scientists see it as mostly irrelevant and ineffective. However, the pact did serve as the legal basis for the concept of a crime against peace, for which the Nuremberg Tribunal and Tokyo Tribunal tried and executed the top leaders responsible for starting World War II. With the signing of the Litvinov Protocol in Moscow on February 9, 1929, the Soviet Union and its western neighbors, including Romania, agreed to put the Kellogg–Briand Pact in effect without waiting for other western signatories to ratify. The Bessarabian Question had made agreement between Romania and the Soviet Union challenging and dispute between the nations over Bessarabia continued. Similar provisions to those in the Kellogg-Briand Pact were later incorporated into the Charter of the United Nations and other treaties, which gave rise to a more activist American foreign policy which began with the signing of the pact.
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  • 24 Nov 2022
Topic Review
Free Basics
Internet.org is a partnership between social networking services company Facebook and six companies (Samsung, Ericsson, MediaTek, Opera Software, Nokia and Qualcomm) that plans to bring affordable access to selected Internet services to less developed countries by increasing efficiency, and facilitating the development of new business models around the provision of Internet access. The app delivering these services was renamed Free Basics in September 2015. As of November 2016, 40 million people are using internet.org. It has been criticized for violating net neutrality, and by handpicking internet services that are included, for discriminating against companies not in the list, including Facebook's rivals. In February 2016, regulators banned the Free Basics service in India based on "Prohibition of Discriminatory Tariffs for Data Services Regulations". The Telecom Regulatory Authority of India (TRAI) accused Facebook of failing to pass on the four questions in the regulator's consultation paper and also blocking access to TRAI's designated email for feedback on Free Basics. On February 11, 2016, Facebook withdrew the Free Basics platform from India.
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  • 24 Nov 2022
Topic Review
JPL Mars Helicopter Scout
The Mars Helicopter Scout (MHS) is a planned robotic helicopter that will test the technology to scout interesting targets for study on Mars, and help plan the best driving route for future Mars rovers. The small drone helicopter will be deployed in 2021 from the planned Mars 2020 rover. It is expected to fly up to five times during its 30-day test campaign, early in the rover's mission, as it is primarily a technology demonstration. Each flight will take no more than 3 minutes, at altitudes ranging from 3 m to 10 m above the ground, but it could potentially cover a maximum distance of about 600 m (2,000 ft) per flight. It will use autonomous control and communicate with the Mars 2020 rover directly after each landing. If it works as expected, NASA will be able to build on the design for future Mars missions. MiMi Aung is the project lead. Other team members are AeroVironment Inc., NASA Ames Research Center, and NASA Langley Research Center.
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  • 24 Nov 2022
Topic Review
Long-Term Memory
Long-term memory (LTM) is the stage of the Atkinson–Shiffrin memory model in which informative knowledge is held indefinitely. It is defined in contrast to short-term and working memory, which persist for only about 18 to 30 seconds. Long-term memory is commonly labelled as explicit memory (declarative), as well as episodic memory, semantic memory, autobiographical memory, and implicit memory (procedural memory).
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  • 24 Nov 2022
Topic Review
Read
In DNA sequencing, a read is an inferred sequence of base pairs (or base pair probabilities) corresponding to all or part of a single DNA fragment. A typical sequencing experiment involves fragmentation of the genome into millions of molecules, which are size-selected and ligated to adapters. The set of fragments is referred to as a sequencing library, which is sequenced to produce a set of reads.
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  • 24 Nov 2022
Topic Review
Goalkeeper CIWS
Goalkeeper is a Dutch close-in weapon system (CIWS) introduced in 1979. It is an autonomous and completely automatic weapon system for short-range defence of ships against highly manoeuvrable missiles, aircraft and fast-manoeuvering surface vessels. Once activated the system automatically undertakes the entire air defence process from surveillance and detection to destruction, including the selection of the next priority target.
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  • 24 Nov 2022
Topic Review
Drinking Bird
Drinking birds, also known as insatiable birdies, dunking birds, drinky birds, water birds, dipping birds, and “Sippy Chickens” are toy heat engines that mimic the motions of a bird drinking from a water source. They are sometimes incorrectly considered examples of a perpetual motion device.
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  • 25 Nov 2022
Topic Review
Tropospheric Ozone
Ozone (O3) is a trace gas of the troposphere, with an average concentration of 20–30 parts per billion by volume (ppbv), with close to 100 ppbv in polluted areas. Ozone is also an important constituent of the stratosphere, where the ozone layer exists which is located between 10 and 50 kilometers above the earths surface. The troposphere is the lowest layer of the Earth's atmosphere. It extends from the ground up to a variable height of approximately 14 kilometers above sea level. Ozone is least concentrated in the ground layer (or planetary boundary layer) of the troposphere. Ground level or tropospheric ozone is created by chemical reactions between oxides of nitrogen (NOx gases) and volatile organic compounds (VOCs). The combination of these chemicals in the presence of sunlight form ozone. Its concentration increases as height above sea level increases, with a maximum concentration at the tropopause. About 90% of total ozone in the atmosphere is in the stratosphere, and 10% is in the troposphere. Although tropospheric ozone is less concentrated than stratospheric ozone, it is of concern because of its health effects. Ozone in the troposphere is considered a greenhouse gas, and may contribute to global warming. Photochemical and chemical reactions involving ozone drive many of the chemical processes that occur in the troposphere by day and by night. At abnormally high concentrations (the largest source being emissions from combustion of fossil fuels), it is a pollutant, and a constituent of smog. Its levels have increased significantly since the industrial revolution, as NOx gasses & VOCs are some of the byproducts of combustion. With more heat and sunlight in the summer months, more ozone is formed which is why regions often experience higher levels of pollution in the summer months. Although the same molecule, ground level ozone can be harmful to our health, unlike stratospheric ozone that protects the earth from excess UV radiation. Photolysis of ozone occurs at wavelengths below approximately 310–320 nanometres. This reaction initiates the chain of chemical reactions that remove carbon monoxide, methane, and other hydrocarbons from the atmosphere via oxidation. Therefore, the concentration of tropospheric ozone affects how long these compounds remain in the air. If the oxidation of carbon monoxide or methane occur in the presence of nitrogen monoxide (NO), this chain of reactions has a net product of ozone added to the system.
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  • 24 Nov 2022
Topic Review
Geodetic Datum
A geodetic datum or geodetic system (also: geodetic reference datum or geodetic reference system) is a coordinate system, and a set of reference points, used for locating places on the Earth (or similar objects). An approximate definition of sea level is the datum WGS 84, an ellipsoid, whereas a more accurate definition is Earth Gravitational Model 2008 (EGM2008), using at least 2,159 spherical harmonics. Other datums are defined for other areas or at other times; ED50 was defined in 1950 over Europe and differs from WGS 84 by a few hundred meters depending on where in Europe you look. Mars has no oceans and so no sea level, but at least two martian datums have been used to locate places there. Datums are used in geodesy, navigation, and surveying by cartographers and satellite navigation systems to translate positions indicated on maps (paper or digital) to their real position on Earth. Each starts with an ellipsoid (stretched sphere), and then defines latitude, longitude and altitude coordinates. One or more locations on the Earth's surface are chosen as anchor "base-points". The difference in co-ordinates between datums is commonly referred to as datum shift. The datum shift between two particular datums can vary from one place to another within one country or region, and can be anything from zero to hundreds of meters (or several kilometers for some remote islands). The North Pole, South Pole and Equator will be in different positions on different datums, so True North will be slightly different. Different datums use different interpolations for the precise shape and size of the Earth (reference ellipsoids). Because the Earth is an imperfect ellipsoid, localised datums can give a more accurate representation of the area of coverage than WGS 84. OSGB36, for example, is a better approximation to the geoid covering the British Isles than the global WGS 84 ellipsoid. However, as the benefits of a global system outweigh the greater accuracy, the global WGS 84 datum is becoming increasingly adopted. Horizontal datums are used for describing a point on the Earth's surface, in latitude and longitude or another coordinate system. Vertical datums measure elevations or depths.
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  • 24 Nov 2022
Topic Review
Westinghouse Lamp Plant
Coordinates: 40°46′53″N 74°11′45″W / 40.78137°N 74.19592°W / 40.78137; -74.19592 The Westinghouse Lamp Plant located in Bloomfield, New Jersey, was one of the lamp manufacturing plants of Westinghouse Electric Corporation. The plant had a major involvement in supplying uranium metal for the world's first self-sustaining chain reaction in Chicago (Chicago Pile-1) in the early phase of the Manhattan Project to create the first atomic bomb.
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  • 24 Nov 2022
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