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🔗 Ondol

🔗 Korea 🔗 Architecture

Ondol (ON-dol; , Korean: 온돌; Hanja: 溫突/溫堗; Korean pronunciation: [on.dol]) or gudeul (구들; [ku.dɯl]) in Korean traditional architecture is underfloor heating that uses direct heat transfer from wood smoke to heat the underside of a thick masonry floor. In modern usage, it refers to any type of underfloor heating, or to a hotel or a sleeping room in Korean (as opposed to Western) style.

The main components of the traditional ondol are an agungi (아궁이; [a.guŋ.i]), a firebox or stove, accessible from an adjoining room (typically kitchen or master bedroom), a raised masonry floor underlain by horizontal smoke passages, and a vertical, freestanding chimney on the opposite exterior wall providing a draft. The heated floor, supported by stone piers or baffles to distribute the smoke, is covered by stone slabs, clay and an impervious layer such as oiled paper.

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  • "Ondol" | 2025-10-26 | 12 Upvotes 1 Comments

🔗 History of Slavery in the Muslim World

🔗 International relations 🔗 Human rights 🔗 History 🔗 Islam 🔗 International relations/International law 🔗 Sociology 🔗 Discrimination 🔗 International relations/United Nations

The history of slavery in the Muslim world began with institutions inherited from pre-Islamic Arabia; and the practice of keeping slaves subsequently developed in radically different ways, depending on social-political factors such as the Arab slave trade. Any non-Muslim could be enslaved. Throughout Islamic history, slaves served in various social and economic roles, from powerful emirs to harshly treated manual laborers. Early on in Muslim history slaves provided plantation labor similar to that in the early-modern Americas, but this practice was abandoned after harsh treatment led to destructive slave revolts, the most notable being the Zanj Rebellion of 869–883. Slaves were widely employed in irrigation, mining, and animal husbandry, but most commonly as soldiers, guards, domestic workers, concubines and sex slaves. Many rulers relied on military slaves (often in huge standing armies) and on slaves in administration - to such a degree that the slaves could sometimes seize power. Among black slaves, there were roughly two females to every one male. Two rough estimates by scholars of the numbers of just one group - black slaves held over twelve centuries in the Muslim world - are 11.5 million and 14 million, while other estimates indicate a number between 12 and 15 million African slaves prior to the 20th century.

Islam encouraged the manumission of Muslim slaves as a way of expiating sins. Many early converts to Islam, such as Bilal, were former slaves. In theory, slavery in Islamic law does not have a racial or color basis, although this has not always been the case in practice. In 1990 the Cairo Declaration on Human Rights in Islam declared that "no one has the right to enslave" another human being. Many slaves were imported from outside the Muslim world.

The Arab slave trade was most active in West Asia, North Africa, and Southeast Africa. The Ottoman slave trade exploited the human resources of eastern and central Europe and the Caucasus; the Barbary Coast slave traders raided the Mediterranean coasts of Europe and as far afield as the British Isles and Iceland. In the early 20th century (post-World War I), authorities gradually outlawed and suppressed slavery in Muslim lands, largely due to pressure exerted by Western nations such as Britain and France. Slavery in the Ottoman Empire was abolished in 1924 when the new Turkish Constitution disbanded the Imperial Harem and made the last concubines and eunuchs free citizens of the newly proclaimed republic. Slavery in Iran was abolished in 1929. Mauritania became the last state to abolish slavery - in 1905, 1981, and again in August 2007. Oman abolished slavery in 1970, and Saudi Arabia and Yemen abolished slavery in 1962 under pressure from Britain. However, slavery claiming the sanction of Islam is documented at present in the predominantly Islamic countries of the Sahel, and is also practiced by ISIS and Boko Haram. It is also practiced in countries like Libya and Mauritania - despite being outlawed.

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🔗 Chatbot Psychosis

🔗 Technology 🔗 Medicine 🔗 Psychology 🔗 Medicine/Psychiatry 🔗 Artificial Intelligence

Chatbot psychosis, also called AI psychosis, is a phenomenon wherein individuals reportedly develop or experience worsening psychosis, such as paranoia and delusions, in connection with their use of chatbots. The term was first suggested in a 2023 editorial by Danish psychiatrist Søren Dinesen Østergaard. It is not a recognized clinical diagnosis.

Journalistic accounts describe individuals who have developed strong beliefs that chatbots are sentient, are channeling spirits, or are revealing conspiracies, sometimes leading to personal crises or criminal acts. Proposed causes include the tendency of chatbots to provide inaccurate information ("hallucinate") and to affirm or validate users' beliefs, or their ability to mimic an intimacy that users do not experience with other humans.

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🔗 LK-99

🔗 Korea 🔗 Physics 🔗 Chemicals 🔗 Electrical engineering 🔗 Materials

LK-99 is a proposed ambient pressure and room-temperature superconductor with a gray‒black appearance.: 8  LK-99 has a hexagonal structure slightly modified from lead‒apatite and is claimed to function as a superconductor below 400 K (127 °C; 260 °F).: 1  The material was investigated by a team of Sukbae Lee et al. from the Korea Institute of Science and Technology (KIST).: 1  As of 26 July 2023 the discovery of LK-99 has not been peer reviewed or independently replicated.

The chemical composition of LK-99 is approximately Pb9Cu(PO4)6O such that—compared to pure lead-apatite (Pb10(PO4)6O): 5 —approximately one quarter of Pb(2) ions are replaced by Cu(II) ions.: 9  This partial replacement of Pb2+ ions (measuring 133 picometre) with Cu2+ ions (measuring 87 picometre) is said to cause a 0.48% reduction in volume, creating internal stress inside the material.: 8 

The internal stress is claimed to cause a heterojunction quantum well between the Pb(1) and oxygen within the phosphate ([PO4]3−) generating a superconducting quantum well (SQW).: 10  Lee et al claim to show LK-99 exhibits a response to a magnetic field (Meissner effect) when chemical vapor deposition is used to apply LK-99 to a non-magnetic copper sample.: 4  Pure lead-apatite is an insulator, but Lee et al claim copper-doped lead-apatite forming LK-99 is a superconductor, or at higher temperatures, a metal.: 5 

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  • "LK-99" | 2023-07-27 | 101 Upvotes 58 Comments

🔗 Organopónicos

🔗 Cuba

Organopónicos or organoponics is a system of urban agriculture using organic gardens. It originated in Cuba and is still mostly focused there. It often consists of low-level concrete walls filled with organic matter and soil, with lines of drip irrigation laid on the surface of the growing media. Organopónicos is a labour-intensive form of local agriculture.

Organopónico farmers employ a wide variety of agroecological techniques including integrated pest management, polyculture, and crop rotation. Most organic materials are also produced within the gardens through composting. This allows production to take place with few petroleum-based inputs.

Organopónicos first arose as a community response to lack of food security during the Special Period after the collapse of the Soviet Union. It is publicly functioning in terms of ownership, access, and management, but heavily subsidized and supported by the Cuban government.

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🔗 Atomic gardening

🔗 Agriculture 🔗 Food and drink 🔗 Plants 🔗 Horticulture and Gardening 🔗 Genetics

Atomic gardening is a form of mutation breeding where plants are exposed to radioactive sources, typically cobalt-60, in order to generate mutations, some of which have turned out to be useful.

The practice of plant irradiation has resulted in the development of over 2000 new varieties of plants, most of which are now used in agricultural production. One example is the resistance to verticillium wilt of the "Todd's Mitcham" cultivar of peppermint which was produced from a breeding and test program at Brookhaven National Laboratory from the mid-1950s. Additionally, the Rio Star Grapefruit, developed at the Texas A&M Citrus Center in the 1970s, now accounts for over three quarters of the grapefruit produced in Texas.

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🔗 Icon (programming language)

🔗 Computing

Icon is a very high-level programming language featuring goal-directed execution and many facilities for managing strings and textual patterns. It is related to SNOBOL and SL5, string processing languages. Icon is not object-oriented, but an object-oriented extension called Idol was developed in 1996 which eventually became Unicon.

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🔗 Floral formula

🔗 Plants

A floral formula is a notation for representing the structure of particular types of flowers. Such notations use numbers, letters and various symbols to convey significant information in a compact form. They may represent the floral form of a particular species, or may be generalized to characterize higher taxa, usually giving ranges of numbers of organs. Floral formulae are one of the two ways of describing flower structure developed during the 19th century, the other being floral diagrams. The format of floral formulae differs according to the tastes of particular authors and periods, yet they tend to convey the same information.

A floral formula is often used along with a floral diagram.

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🔗 Nika Riots (532 C.E.)

🔗 Classical Greece and Rome 🔗 Greece 🔗 Middle Ages 🔗 Middle Ages/History 🔗 Sociology 🔗 Sports 🔗 Greece/Byzantine world

The Nika riots (Greek: Στάσις τοῦ Νίκα, romanized: Stásis toû Níka), Nika revolt or Nika sedition took place against Byzantine emperor Justinian I in Constantinople over the course of a week in 532 C.E. They are often regarded as the most violent riots in the city's history, with nearly half of Constantinople being burned or destroyed and tens of thousands of people killed.

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🔗 Fairfax, California B-17 Crash in 1946

🔗 California

Early on the morning of May 16, 1946, a U.S. Army B-17 Flying Fortress aircraft crashed into White's Hill (also known locally as "White Hill") near Fairfax, California. Two men were killed and six seriously injured. There were reports that the B-17 was carrying nuclear weapons materials for the Operation Crossroads tests at Bikini atoll, but these reports were not confirmed. However, due to the behavior and activities of the military authorities at the crash site and the reports of several credible witnesses, including several of the crewmembers, questions about the plane's cargo remain.

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