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🔗 Germany 🔗 Bridges and Tunnels

The Magdeburg Water Bridge (German: Kanalbrücke Magdeburg) is a large navigable aqueduct in central Germany, located near Magdeburg. The largest canal underbridge in Europe, it spans the river Elbe and directly connects the Mittellandkanal to the west and Elbe-Havel Canal to the east of the river, allowing large commercial ships to pass between the Rhineland and Berlin without having to descend into and then climb out of the Elbe itself.

🔗 Human rights 🔗 Soviet Union 🔗 Russia 🔗 Military history 🔗 Crime 🔗 Death 🔗 Socialism 🔗 Poland 🔗 Military history/World War II 🔗 Military history/Russian, Soviet and CIS military history 🔗 Russia/history of Russia 🔗 Military history/Polish military history 🔗 Military history/European military history

The Katyn massacre (Polish: zbrodnia katyńska, "Katyń crime"; Russian: Катынская резня Katynskaya reznya, "Katyn massacre", or Russian: Катынский расстрел, "Katyn execution by shooting") was a series of mass executions of about 22,000 Polish military officers and intelligentsia carried out by the Soviet Union, specifically the NKVD ("People's Commissariat for Internal Affairs", the Soviet secret police) in April and May 1940. Though the killings also occurred in the Kalinin and Kharkiv prisons and elsewhere, the massacre is named after the Katyn Forest, where some of the mass graves were first discovered.

The massacre was initiated in NKVD chief Lavrentiy Beria's proposal of 5 March 1940 to execute all captive members of the Polish officer corps, approved by the Soviet Politburo led by Joseph Stalin. Of the total killed, about 8,000 were officers imprisoned during the 1939 Soviet invasion of Poland, another 6,000 were police officers, and the remaining 8,000 were Polish intelligentsia the Soviets deemed to be "intelligence agents, gendarmes, landowners, saboteurs, factory owners, lawyers, officials, and priests". The Polish Army officer class was representative of the multi-ethnic Polish state; the murdered included ethnic Poles, Polish Ukrainians, Belarusians, and Polish Jews including the Chief Rabbi of the Polish Army, Baruch Steinberg.

The government of Nazi Germany announced the discovery of mass graves in the Katyn Forest in April 1943. Stalin severed diplomatic relations with the London-based Polish government-in-exile when it asked for an investigation by the International Committee of the Red Cross. The USSR claimed the Nazis had killed the victims, and it continued to deny responsibility for the massacres until 1990, when it officially acknowledged and condemned the killings by the NKVD, as well as the subsequent cover-up by the Soviet government.

An investigation conducted by the office of the Prosecutors General of the Soviet Union (1990–1991) and the Russian Federation (1991–2004) confirmed Soviet responsibility for the massacres, but refused to classify this action as a war crime or as an act of mass murder. The investigation was closed on the grounds the perpetrators were dead, and since the Russian government would not classify the dead as victims of the Great Purge, formal posthumous rehabilitation was deemed inapplicable.

In November 2010, the Russian State Duma approved a declaration blaming Stalin and other Soviet officials for ordering the massacre.

🔗 Computer science

In computer science, a skip list is a data structure that allows ${\displaystyle {\mathcal {O}}(\log n)}$ search complexity as well as ${\displaystyle {\mathcal {O}}(\log n)}$ insertion complexity within an ordered sequence of ${\displaystyle n}$ elements. Thus it can get the best features of an array (for searching) while maintaining a linked list-like structure that allows insertion, which is not possible in an array. Fast search is made possible by maintaining a linked hierarchy of subsequences, with each successive subsequence skipping over fewer elements than the previous one (see the picture below on the right). Searching starts in the sparsest subsequence until two consecutive elements have been found, one smaller and one larger than or equal to the element searched for. Via the linked hierarchy, these two elements link to elements of the next sparsest subsequence, where searching is continued until finally we are searching in the full sequence. The elements that are skipped over may be chosen probabilistically or deterministically, with the former being more common.

🔗 United States 🔗 United States/Texas 🔗 U.S. Roads/U.S. Route 66

Cadillac Ranch is a public art installation and sculpture in Amarillo, Texas, US. It was created in 1974 by Chip Lord, Hudson Marquez and Doug Michels, who were a part of the art group Ant Farm.

The installation consists of ten Cadillacs (1949–1963) buried nose-first in the ground. Installed in 1974, the cars were either older running, used or junk cars — together spanning the successive generations of the car line — and the defining evolution of their tailfins. The cars are inclined at the same angle as the pyramids at Giza.

🔗 Georgia (U.S. state) 🔗 Caves

Ellison's Cave is a pit cave located in Walker County, on Pigeon Mountain in the Appalachian Plateaus of Northwest Georgia. It is the 12th deepest cave in the United States and features the deepest, unobstructed pit in the continental US named Fantastic Pit. The cave is over 12 miles long and extends 1063 feet vertically.

🔗 Human rights

🔗 Business 🔗 Game theory

A Keynesian beauty contest is a concept developed by John Maynard Keynes and introduced in Chapter 12 of his work, The General Theory of Employment, Interest and Money (1936), to explain price fluctuations in equity markets.

🔗 Law Enforcement 🔗 Chicago

A police riot is a riot carried out by the police; a riot that the police are responsible for instigating, escalating or sustaining as a violent confrontation; an event characterized by widespread police brutality; a mass police action that is violently undertaken against civilians for the purpose of political repression. The term "police riot" was popularized after its use in the Walker Report, which investigated the events surrounding the 1968 Democratic National Convention in Chicago to describe the "unrestrained and indiscriminate" violence that the police "inflicted upon persons who had broken no law, disobeyed no order, made no threat." In this sense a police riot refers to rioting carried out by the police (or those acting in a police capacity) rather than a riot carried out by people who may be motivated to a greater or lesser degree by grievances with the police (see the 1981 Toxteth riots or the 1992 Los Angeles Riots for examples of riots over policing rather than police riots).

🔗 China 🔗 Economics

Made in China 2025 (Chinese: 中国制造2025; pinyin: Zhōngguózhìzào èrlíng'èrwǔ) (MIC25, MIC 2025, or MIC2025) is a national strategic plan and industrial policy of the Chinese Communist Party (CCP) to further develop the manufacturing sector of China, issued by CCP general secretary Xi Jinping and Chinese Premier Li Keqiang's cabinet in May 2015. As part of the Thirteenth and Fourteenth Five-year Plans, China aims to move away from being the "world's factory"—a producer of cheap low-tech goods facilitated by lower labour costs and supply chain advantages. The industrial policy aims to upgrade the manufacturing capabilities of Chinese industries, growing from labor-intensive workshops into a more technology-intensive powerhouse.

Made in China 2025's goals include increasing the Chinese-domestic content of core materials to 40 percent by 2020 and 70 percent by 2025. To help achieve independence from foreign suppliers, the initiative encourages increased production in high-tech products and services, with its semiconductor industry central to the industrial plan, partly because advances in chip technology may "lead to breakthroughs in other areas of technology, handing the advantage to whoever has the best chips – an advantage that currently is out of Beijing’s reach."

Since 2018, following a backlash from the U.S., Europe, and elsewhere, the phrase "MIC 2025" has been de-emphasized in government and other official communications, while the program remains in place. The Chinese government continues to invest heavily in identified technologies. In 2018, the Chinese government committed to investing roughly US$300 billion into achieving the industrial plan. In the wake of the COVID-19 pandemic, at least an additional $1.4 trillion was also invested into MIC 2025 initiatives. Given China's current middle income country status, the practicality of its disproportionate expenditure on pioneering new technologies has been called into question.

🔗 United States 🔗 African diaspora 🔗 Holidays 🔗 United States/Texas 🔗 United States/U.S. history 🔗 Black Lives Matter 🔗 Project-independent assessment 🔗 Houston

Juneteenth is a federal holiday in the United States. It is celebrated annually on June 19 to commemorate the ending of slavery in the United States. The holiday's name, first used in the 1890s, is a portmanteau of the words "June" and "nineteenth", referring to June 19, 1865, the day when Major General Gordon Granger ordered the final enforcement of the Emancipation Proclamation in Texas at the end of the American Civil War. In the Civil War period, slavery came to an end in various areas of the United States at different times. Many enslaved Southerners escaped, demanded wages, stopped work, or took up arms against the Confederacy of slave states. In January 1865, Congress finally proposed the Thirteenth Amendment to the United States Constitution for the national abolition of slavery. By June 1865, almost all enslaved persons had been freed by the victorious Union Army or by state abolition laws. When the national abolition amendment was ratified in December, the remaining enslaved people in Delaware and in Kentucky were freed.

Early Juneteenth celebrations date back to 1866, at first involving church-centered community gatherings in Texas. They spread across the South among newly freed African-Americans and their descendants and became more commercialized in the 1920s and 1930s, often centering on a food festival. Participants in the Great Migration brought these celebrations to the rest of the country. During the Civil Rights Movement of the 1960s, these celebrations were eclipsed by the nonviolent determination to achieve civil rights, but grew in popularity again in the 1970s with a focus on African-American freedom and African-American arts. Beginning with Texas by proclamation in 1938, and by legislation in 1979, every U.S. state and the District of Columbia has formally recognized the holiday in some way.

Juneteenth is also celebrated by the Mascogos, descendants of Black Seminoles who escaped from slavery in 1852 and settled in Coahuila, Mexico.

The day was recognized as a federal holiday in 2021, when the 117th U.S. Congress enacted and President Joe Biden signed the Juneteenth National Independence Day Act into law. Juneteenth became the first new federal holiday since Martin Luther King Jr. Day was adopted in 1983.