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🔗 United States 🔗 Biography 🔗 Women's History 🔗 Wisconsin 🔗 United States/Massachusetts - Cape Cod and the Islands

Rose Marie "Rosemary" Kennedy (September 13, 1918 – January 7, 2005) was the eldest daughter born to Joseph P. Kennedy Sr. and Rose Fitzgerald Kennedy. She was a sister of President John F. Kennedy and Senators Robert F. and Ted Kennedy.

In her early young adult years, Rosemary Kennedy experienced seizures and violent mood swings. In response to these issues, her father arranged a prefrontal lobotomy for her in 1941 when she was 23 years of age; the procedure left her permanently incapacitated and rendered her unable to speak intelligibly.

Rosemary Kennedy spent most of the rest of her life being cared for at St. Coletta, an institution in Jefferson, Wisconsin. The truth about her situation and whereabouts was kept secret for decades. While she was initially isolated from her siblings and extended family following her lobotomy, Rosemary did go on to visit them during her later life.

🔗 Africa 🔗 Africa/Ghana 🔗 Food and drink 🔗 Africa/Ivory Coast 🔗 Africa/French Africa

Child labour is a recurring issue in cocoa production. Cote d’Ivoire (also known in English as Ivory Coast) and Ghana, together produce nearly 60% of the world's cocoa each year. During the 2018/19 cocoa-growing season, research commissioned by the U.S. Department of Labor was conducted by NORC at the University of Chicago in these two countries and found that 1.48 million children are engaged in hazardous work on cocoa farms including working with sharp tools and agricultural chemicals and carrying heavy loads. That number of children is significant, representing 43 percent of all children living in agricultural households in cocoa growing areas. During the same period cocoa production in Cote d’Ivoire and Ghana increased 62 percent while the prevalence of child labour in cocoa production among all agricultural households increased 14 percentage points. Attention on this subject has focused on West Africa, which collectively supplies 69% of the world's cocoa, and Côte d'Ivoire, supplying 35%, in particular. The 2016 Global Estimates of Child Labour indicate that one-fifth of all African children are involved in child labour. Nine percent of African children are in hazardous work. It is estimated that more than 1.8 million children in West Africa are involved in growing cocoa. A 2013–14 survey commissioned by the Department of Labor and conducted by Tulane University found that an estimated 1.4 million children aged 5 years old to 11 years old worked in agriculture in cocoa-growing areas, while approximately 800,000 of them were engaged in hazardous work, including working with sharp tools and agricultural chemicals and carrying heavy loads. According to the NORC study, methodological differences between the 2018/9 survey and earlier ones, together with errors in the administration of the 2013/4 survey have made it challenging to document changes in the number of children engaged in child labour over the past five years.

A major study of the issue, published in Fortune magazine in the U.S. in March 2016, concluded that approximately 2.1 million children in West Africa "still do the dangerous and physically taxing work of harvesting cocoa". The report was doubtful as to whether the situation can be improved significantly.

🔗 Canada 🔗 Minnesota 🔗 Canada/Geography of Canada 🔗 National Register of Historic Places

The northwesternmost point of the Lake of the Woods was a critical landmark for the boundary between U.S. territory and the British possessions to the north. This point was referred to in the Treaty of Paris in 1783 and in later treaties including the Treaty of 1818. This point lies at the corner of the Northwest Angle of Minnesota and is thus the northernmost point in the lower 48 United States. After Canadian Confederation, the point became the basis for the border between Manitoba and Ontario.

The "northwesternmost point" of the lake had not yet been identified when it was referenced in treaties defining the border between the US and Britain; it was simply an easily described abstraction based on a large landmark. The best maps at the time of the original negotiation depicted the lake as a simple oval. However, although the southern portion of the lake is easily mapped, to the north it becomes a complex tangle of bays, peninsulas, and islands, with many adjacent bodies of water separated or connected by narrow isthmuses or straits. An 1822 survey crew declared the referenced point impossible to determine. In 1824, British explorer David Thompson was hired to identify it. Thompson mapped the lake and found four possibilities, but did not conclusively declare one location.

In 1825, German astronomer in British service Dr. Johann Ludwig Tiarks surveyed the lake. Tiarks identified two possibilities for the northwesternmost point on the lake, based on Thompson's maps: the Angle Inlet and Rat Portage. To determine which point was the most northwestern, he drew a line from each point in the southwest-northeast direction. If the line intersected the lake at any point, it was not the most northwestern point, as shown in the example diagram here. Tiarks determined that the only such line that did not intersect the lake was at the edge of a pond on the Angle Inlet. (A 1940 academic study documents this point as being in the immediate vicinity of 49°23′51.324″N 95°9′12.20783″W (NAD83).)

Under the 1783 treaty, the international border would have run due west from this point to the Mississippi River. As this was determined to be geographically impossible (the Mississippi begins further south), under the 1818 treaty the international border instead ran from the point determined by Tiarks, to the 49th parallel. (It was not known at the time whether that was to the north or – in fact – the south.) From there it ran due west to the Rocky Mountains (and later, the Pacific coast).

Tiarks' point, however, created problems, because the 1818 treaty called for the border to run directly north–south from it. South of that point, the channel of the Northwest Angle Inlet meandered east and west, crossing the border five times, thereby creating two small enclaves of water areas totaling two and a half acres that belonged to the United States but were surrounded by Canadian waters. A 1925 treaty addressed this by adopting the southernmost of the points where the channel and the border intersected – approximately 5,000 ft (1,500 m) south of Tiarks' point – as the new "northwesternmost point". The new northwesternmost point thus became 49°23′4.14″N 95°9′11.34″W, based on the NAD27 datum, which is equivalent to 49°23′4.12373″N 95°9′12.20783″W under the modern NAD83 datum.

🔗 Philosophy 🔗 Classical Greece and Rome 🔗 Greece 🔗 Philosophy/Social and political philosophy 🔗 Women's History 🔗 Philosophy/Ancient philosophy

Aristotle's views on women influenced later Western thinkers, as well as Islamic thinkers, who quoted him as an authority until the end of the Middle Ages, influencing women's history.

In his Politics, Aristotle saw women as subject to men, but as higher than slaves, and lacking authority; he believed the husband should exert political rule over the wife. Among women's differences from men were that they were, in his view, more impulsive, more compassionate, more complaining, and more deceptive. He gave the same weight to women's happiness as to men's, and in his Rhetoric stated that society could not be happy unless women were happy too. Whereas Plato was open to the potential equality of men and women, stating both that women were not equal to men in terms of strength and virtue, but were equal to men in terms of rational and occupational capacity, and hence in the ideal Republic should be educated and allowed to work alongside men without differentiation, Aristotle appears to have disagreed.

In his theory of inheritance, Aristotle considered the mother to provide a passive material element to the child, while the father provided an active, ensouling element with the form of the human species.

🔗 Animals

Tardigrades (), known colloquially as water bears or moss piglets, are a phylum of water-dwelling eight-legged segmented micro-animals. They were first described by the German zoologist Johann August Ephraim Goeze in 1773, who called them little water bears. In 1777, the Italian biologist Lazzaro Spallanzani named them Tardigrada, which means "slow steppers".

They have been found everywhere, from mountaintops to the deep sea and mud volcanoes, and from tropical rainforests to the Antarctic. Tardigrades are among the most resilient animals known, with individual species able to survive extreme conditions—such as exposure to extreme temperatures, extreme pressures (both high and low), air deprivation, radiation, dehydration, and starvation—that would quickly kill most other known forms of life. Tardigrades have survived exposure to outer space. About 1,300 known species form the phylum Tardigrada, a part of the superphylum Ecdysozoa. The earliest known true members of the group are known from Cretaceous amber in North America, but are essentially modern forms, and therefore likely have a significantly earlier origin, as they diverged from their closest relatives in the Cambrian, over 500 million years ago.

Tardigrades are usually about 0.5 mm (0.02 in) long when fully grown. They are short and plump, with four pairs of legs, each ending in claws (usually four to eight) or sucking disks. Tardigrades are prevalent in mosses and lichens and feed on plant cells, algae, and small invertebrates. When collected, they may be viewed under a low-power microscope, making them accessible to students and amateur scientists.

🔗 Mathematics

Hilbert's twenty-fourth problem is a mathematical problem that was not published as part of the list of 23 problems known as Hilbert's problems but was included in David Hilbert's original notes. The problem asks for a criterion of simplicity in mathematical proofs and the development of a proof theory with the power to prove that a given proof is the simplest possible.

The 24th problem was rediscovered by German historian Rüdiger Thiele in 2000, noting that Hilbert did not include the 24th problem in the lecture presenting Hilbert's problems or any published texts. Hilbert's friends and fellow mathematicians Adolf Hurwitz and Hermann Minkowski were closely involved in the project but did not have any knowledge of this problem.

This is the full text from Hilbert's notes given in Rüdiger Thiele's paper. The section was translated by Rüdiger Thiele.

The 24th problem in my Paris lecture was to be: Criteria of simplicity, or proof of the greatest simplicity of certain proofs. Develop a theory of the method of proof in mathematics in general. Under a given set of conditions there can be but one simplest proof. Quite generally, if there are two proofs for a theorem, you must keep going until you have derived each from the other, or until it becomes quite evident what variant conditions (and aids) have been used in the two proofs. Given two routes, it is not right to take either of these two or to look for a third; it is necessary to investigate the area lying between the two routes. Attempts at judging the simplicity of a proof are in my examination of syzygies and syzygies [Hilbert misspelled the word syzygies] between syzygies (see Hilbert 42, lectures XXXII–XXXIX). The use or the knowledge of a syzygy simplifies in an essential way a proof that a certain identity is true. Because any process of addition [is] an application of the commutative law of addition etc. [and because] this always corresponds to geometric theorems or logical conclusions, one can count these [processes], and, for instance, in proving certain theorems of elementary geometry (the Pythagoras theorem, [theorems] on remarkable points of triangles), one can very well decide which of the proofs is the simplest. [Author's note: Part of the last sentence is not only barely legible in Hilbert's notebook but also grammatically incorrect. Corrections and insertions that Hilbert made in this entry show that he wrote down the problem in haste.]

🔗 Technology 🔗 Environment 🔗 Automobiles 🔗 Environment/Green vehicle

A compressed-air car is a compressed-air vehicle powered by pressure vessels filled with compressed air. It is propelled by the release and expansion of the air within a motor adapted to compressed air. The car might be powered solely by air, or combined (as in a hybrid electric vehicle) with other fuels such as gasoline, diesel, or an electric plant with regenerative braking.

Compressed-air cars use a thermodynamic process. Air cools when expanding and heats when compressed. Thermal energy losses in the compressor and tankage reduce the capacity factor of compressed air systems.

This technology might develop into an inexpensive, clean transportation technology. The energy, vehicles and compressors might be produced easily by decentralized methods, even circular industry. Using plastic might permit open source fabrication using numerical control, including additive manufacturing. The compressed air for such vehicles might be produced easily by common types of renewable energy. For example, multistage air compressors and intercoolers or hydraulic pumps might be attached directly to trompes, hydropower, VAWT wind turbines or stirling engines using a solar concentrator. Direct mechanical compression avoids the Carnot inefficiencies of heat engines. Insulated storage of compressed air avoids energy conversion and battery storage. Heat-based systems might use tankage of solar-heated molten salts driving a heat exchanger rather than an onboard heat recovery system. Electric energy, electric grids and their issues might be avoided.

🔗 France 🔗 Architecture 🔗 Catholicism

The Cathedral of Saint Peter of Beauvais (French: Cathédrale Saint-Pierre de Beauvais) is a Roman Catholic church in the northern town of Beauvais, Oise, France. It is the seat of the Bishop of Beauvais, Noyon and Senlis.

The cathedral is in the Gothic style, and consists of a 13th-century choir, with an apse and seven polygonal apsidal chapels reached by an ambulatory, joined to a 16th-century transept.

It has the highest Gothic choir in the world: (48.50 m) under vault. From 1569 to 1573 the cathedral of Beauvais was, with its tower of 153 meters, the highest human construction of the world. Its designers had the ambition to make it the largest gothic cathedral in France ahead of Amiens. Victim of two collapses, one in the 13th century, the other in the 16th century, it remains unfinished today; only the choir and the transept have been built.

The planned nave of the cathedral was never constructed. The remnant of the previous 10th-century Romanesque cathedral, known as the Basse Œuvre ("Lower Work"), still occupies the intended site of the nave.

🔗 Chemistry

Aqua regia (; from Latin, lit. "regal water" or "king's water") is a mixture of nitric acid and hydrochloric acid, optimally in a molar ratio of 1:3. Aqua regia is a yellow-orange (sometimes red) fuming liquid, so named by alchemists because it can dissolve the noble metals, gold and platinum, though not all metals.

🔗 Amateur radio 🔗 Michigan

Heathkit is the brand name of kits and other electronic products produced and marketed by the Heath Company. The products over the decades have included electronic test equipment, high fidelity home audio equipment, television receivers, amateur radio equipment, robots, electronic ignition conversion modules for early model cars with point style ignitions, and the influential Heath H-8, H-89, and H-11 hobbyist computers, which were sold in kit form for assembly by the purchaser.

Heathkit manufactured electronic kits from 1947 until 1992. After closing that business, the Heath Company continued with its products for education, and motion-sensor lighting controls. The lighting control business was sold around 2000. The company announced in 2011 that they were reentering the kit business after a 20-year hiatus but then filed for bankruptcy in 2012, and under new ownership began restructuring in 2013. As of 2019, the company has a live website with newly-designed products, services, vintage kits, and replacement parts for sale.