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🔗 Computing 🔗 Computing/Software 🔗 Computing/Free and open-source software

netcat (often abbreviated to nc) is a computer networking utility for reading from and writing to network connections using TCP or UDP. The command is designed to be a dependable back-end that can be used directly or easily driven by other programs and scripts. At the same time, it is a feature-rich network debugging and investigation tool, since it can produce almost any kind of connection its user could need and has a number of built-in capabilities.

Its list of features includes port scanning, transferring files, and port listening, and it can be used as a backdoor.

🔗 Numbers

The number 6174 is known as Kaprekar's constant after the Indian mathematician D. R. Kaprekar. This number is renowned for the following rule:

1. Take any four-digit number, using at least two different digits (leading zeros are allowed).
2. Arrange the digits in descending and then in ascending order to get two four-digit numbers, adding leading zeros if necessary.
3. Subtract the smaller number from the bigger number.
4. Go back to step 2 and repeat.

The above process, known as Kaprekar's routine, will always reach its fixed point, 6174, in at most 7 iterations. Once 6174 is reached, the process will continue yielding 7641 – 1467 = 6174. For example, choose 1459:

The only four-digit numbers for which Kaprekar's routine does not reach 6174 are repdigits such as 1111, which give the result 0000 after a single iteration. All other four-digit numbers eventually reach 6174 if leading zeros are used to keep the number of digits at 4. For numbers with three identical numbers and a fourth number that is one number higher or lower (such as 2111), it is essential to treat 3-digit numbers with a leading zero; for example: 2111 – 1112 = 0999; 9990 – 999 = 8991; 9981 – 1899 = 8082; 8820 – 288 = 8532; 8532 – 2358 = 6174.

🔗 Biography 🔗 Military history 🔗 Politics 🔗 Military history/Military biography 🔗 Biography/military biography 🔗 Military history/Cold War 🔗 Biography/politics and government 🔗 Military history/South American military history 🔗 Uruguay

José Alberto "Pepe" Mujica Cordano (Spanish: [xoˈse muˈxika]; born 20 May 1935) is a Uruguayan politician and farmer who served as the 40th President of Uruguay from 2010 to 2015. A former guerrilla with the Tupamaros, he was tortured and imprisoned for 14 years during the military dictatorship in the 1970s and 1980s. A member of the Broad Front coalition of left-wing parties, Mujica was Minister of Livestock, Agriculture, and Fisheries from 2005 to 2008 and a Senator afterwards. As the candidate of the Broad Front, he won the 2009 presidential election and took office as President on 1 March 2010.

He has been described as "the world's humblest head of state" due to his austere lifestyle and his donation of around 90 percent of his $12,000 monthly salary to charities that benefit poor people and small entrepreneurs. An outspoken critic of capitalism’s focus on stockpiling material possessions which do not contribute to human happiness, Pepe is often seen riding his 60-year-old bicycle. The Times Higher Education called him the "philosopher president" in 2015, a play on words of Plato's conception of the philosopher king.

🔗 Time 🔗 Writing

Kairos (Ancient Greek: καιρός) is an Ancient Greek word meaning the right, critical, or opportune moment. The ancient Greeks had two words for time: chronos (χρόνος) and kairos. The former refers to chronological or sequential time, while the latter signifies a proper or opportune time for action. While chronos is quantitative, kairos has a qualitative, permanent nature. Kairos also means weather in Modern Greek. The plural, καιροί (kairoi (Ancient and Modern Greek)) means the times. Kairos is a term, idea, and practice that has been applied in several fields including classical rhetoric, modern rhetoric, digital media, Christian theology, and science.

🔗 Technology 🔗 Computing 🔗 Medicine 🔗 Molecular and Cell Biology 🔗 Medicine/Medical genetics

DNA digital data storage is the process of encoding and decoding binary data to and from synthesized strands of DNA.

While DNA as a storage medium has enormous potential because of its high storage density, its practical use is currently severely limited because of its high cost and very slow read and write times.

In June 2019, scientists reported that all 16 GB of text from Wikipedia's English-language version have been encoded into synthetic DNA.

🔗 Mathematics

A sequence of six 9's occurs in the decimal representation of the number pi (π), starting at the 762nd decimal place. It has become famous because of the mathematical coincidence and because of the idea that one could memorize the digits of π up to that point, recite them and end with "nine nine nine nine nine nine and so on", which seems to suggest that π is rational. The earliest known mention of this idea occurs in Douglas Hofstadter's 1985 book Metamagical Themas, where Hofstadter states

I myself once learned 380 digits of π, when I was a crazy high-school kid. My never-attained ambition was to reach the spot, 762 digits out in the decimal expansion, where it goes "999999", so that I could recite it out loud, come to those six 9's, and then impishly say, "and so on!"

This sequence of six nines is sometimes called the "Feynman point", after physicist Richard Feynman, who allegedly stated this same idea in a lecture. It is not clear when, or even if, Feynman made such a statement, however; it is not mentioned in published biographies or in his autobiographies, and is unknown to his biographer, James Gleick.

🔗 Internet 🔗 Computing 🔗 Computing/Computer hardware 🔗 Finance & Investment 🔗 Economics 🔗 Law 🔗 Computing/Software 🔗 Computing/Free and open-source software 🔗 Computing/Computer science 🔗 Cryptography 🔗 Cryptography/Computer science 🔗 Numismatics 🔗 Guild of Copy Editors 🔗 Numismatics/Cryptocurrency 🔗 Cryptocurrency 🔗 Open 🔗 Computing/Computer Security

Bitcoin (₿) is a cryptocurrency. It is a decentralized digital currency without a central bank or single administrator that can be sent from user to user on the peer-to-peer bitcoin network without the need for intermediaries.

Transactions are verified by network nodes through cryptography and recorded in a public distributed ledger called a blockchain. Bitcoin was invented in 2008 by an unknown person or group of people using the name Satoshi Nakamoto and started in 2009 when its source code was released as open-source software. Bitcoins are created as a reward for a process known as mining. They can be exchanged for other currencies, products, and services. Research produced by University of Cambridge estimates that in 2017, there were 2.9 to 5.8 million unique users using a cryptocurrency wallet, most of them using bitcoin.

Bitcoin has been criticized for its use in illegal transactions, its high electricity consumption, price volatility, and thefts from exchanges. Some economists, including several Nobel laureates, have characterized it as a speculative bubble. Bitcoin has also been used as an investment, although several regulatory agencies have issued investor alerts about bitcoin.

🔗 Canada 🔗 Indigenous peoples of North America 🔗 Canada/Education in Canada 🔗 Canada/The 10,000 Challenge

In Canada, the Indian residential school system was a network of boarding schools for Indigenous peoples which amounted to cultural genocide. The network was funded by the Canadian government's Department of Indian Affairs and administered by Christian churches. The school system was created to isolate Indigenous children from the influence of their own native culture and religion in order to assimilate them into the dominant Canadian culture.^: 42 Over the course of the system's more than hundred-year existence, around 150,000 children were placed in residential schools nationally.^: 2–3 By the 1930s about 30 percent of Indigenous children were believed to be attending residential schools. The number of school-related deaths remains unknown due to incomplete records. Estimates range from 3,200 to over 30,000.

The system had its origins in laws enacted before Confederation, but it was primarily active from the passage of the Indian Act in 1876, under Prime Minister Alexander MacKenzie. Under Prime Minister John A. Macdonald, the government adopted the residential industrial school system of the United States, a partnership between the government and various church organizations. An amendment to the Indian Act in 1894, under Prime Minister Mackenzie Bowell, made attendance at day schools, industrial schools, or residential schools compulsory for First Nations children. Due to the remote nature of many communities, school locations meant that for some families, residential schools were the only way to comply. The schools were intentionally located at substantial distances from Indigenous communities to minimize contact between families and their children. Indian Commissioner Hayter Reed argued for schools at greater distances to reduce family visits, which he thought counteracted efforts to assimilate Indigenous children. Parental visits were further restricted by the use of a pass system designed to confine Indigenous peoples to reserves. The last federally-funded residential school, Kivalliq Hall in Rankin Inlet, closed in 1997. Schools operated in every province and territory with the exception of New Brunswick and Prince Edward Island.

The residential school system harmed Indigenous children significantly by removing them from their families, depriving them of their ancestral languages, and exposing many of them to physical and sexual abuse. Conditions in the schools led to student malnutrition, starvation, and disease. Students were also subjected to forced enfranchisement as "assimilated" citizens that removed their legal identity as Indians. Disconnected from their families and culture and forced to speak English or French, students who attended the residential school system often graduated being unable to fit into their communities but remaining subject to racist attitudes in mainstream Canadian society. The system ultimately proved successful in disrupting the transmission of Indigenous practices and beliefs across generations. The legacy of the system has been linked to an increased prevalence of post-traumatic stress, alcoholism, substance abuse, suicide, and intergenerational trauma which persist within Indigenous communities today.

Starting in the late 2000s, the Canadian government and religious communities have begun to recognize, and issue apologies for, their respective roles in the residential school system. Prime Minister Stephen Harper offered a public apology on his behalf and that of the other federal political party leaders. Nine days prior, on June 1, 2008, the Truth and Reconciliation Commission (TRC) was established to uncover the truth about the schools. The commission gathered about 7,000 statements from residential school survivors through public and private meetings at various local, regional and national events across Canada. Seven national events held between 2008 and 2013 commemorated the experience of former students of residential schools. In 2015, the TRC concluded with the establishment of the National Centre for Truth and Reconciliation and the publication of a multi-volume report detailing the testimonies of survivors and historical documents from the time. The TRC report concluded that the school system amounted to cultural genocide. Ongoing efforts since 2021 have identified thousands of probable unmarked graves on the grounds of former residential schools, though no human remains have yet to be exhumed. During a penitential pilgrimage to Canada in July 2022, Pope Francis reiterated the apologies of the Catholic Church for its role in administering many of the residential schools, also acknowledging the system as genocide. In October 2022, the House of Commons unanimously passed a motion calling on the federal Canadian government to recognize residential schools as genocide.

🔗 United States 🔗 International relations 🔗 Soviet Union 🔗 Agriculture 🔗 Trade 🔗 Soviet Union/economy of Russia

The great grain robbery was the July 1972 purchase of 10 million tons of grain (mainly wheat and corn) from the United States by the Soviet Union at subsidized prices, which caused global grain prices to soar. Crop shortfalls in 1971 and 1972 forced the Soviet Union to look abroad for grain, hoping to prevent famine or crisis. Soviet negotiators worked out a deal to buy grain on credit, but quickly exceeded their credit limit. The American negotiators did not realize that both the Soviets and the world grain market had suffered shortfalls, and thus chose to subsidize the purchase. The strategy backfired and intensified the crisis with global food prices rose at least 30%, and grain stockpiles were decimated.