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🔗 Computing 🔗 Computing/Software 🔗 Linux

The x32 ABI is an application binary interface (ABI) and one of the interfaces of the Linux kernel. It allows programs to take advantage of the benefits of x86-64 instruction set (larger number of CPU registers, better floating-point performance, faster position-independent code, shared libraries, function parameters passed via registers, faster syscall instruction) while using 32-bit pointers and thus avoiding the overhead of 64-bit pointers.

🔗 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.

🔗 Ships

A sea anchor (also known as a parachute anchor, drift anchor, drift sock, para-anchor or boat brake) is a device that is streamed from a boat in heavy weather. Its purpose is to stabilize the vessel and to limit progress through the water. Rather than tethering the boat to the seabed with a conventional anchor, a sea anchor provides hydrodynamic drag, thereby acting as a brake. Normally attached to a vessel's bows, a sea anchor can prevent the vessel from turning broadside to the waves and being overwhelmed by them.

Early sea anchors were crude devices, but today most take the form of a marine drogue parachute. These are so efficient that they need a tripping line to collapse the parachute for retrieval. Being made of fabric, a sea parachute may be bagged and easily stowed when not in use.

A similar device to the sea anchor is the much smaller drogue, which is streamed from a vessel's stern in strong winds so as to slow the boat to prevent pitchpoling or broaching in an overtaking sea. The fundamental difference between the sea anchor and the drogue is that the drogue will slow the boat while keeping the heading steady, and is intended to be launched from the stern. The parachute anchor is designed to be launched from the bow and effectively stop the boat's progress relative to the current in an open sea.

🔗 Geography 🔗 Mountains

A gravity hill, also known as a magnetic hill, mystery hill, mystery spot, gravity road, or anti-gravity hill, is a place where the layout of the surrounding land produces an optical illusion, making a slight downhill slope appear to be an uphill slope. Thus, a car left out of gear will appear to be rolling uphill against gravity. There are hundreds of recognized gravity hills around the world.

The slope of gravity hills is an optical illusion, although sites are often accompanied by claims that magnetic or supernatural forces are at work. The most important factor contributing to the illusion is a completely or mostly obstructed horizon. Without a horizon, it becomes difficult to judge the slope of a surface as a reliable reference is missing. Objects which one would normally assume to be more or less perpendicular to the ground, such as trees, may actually be leaning, offsetting the visual reference.

A 2003 study looked into how the absence of a horizon can skew the perspective on gravity hills by recreating a number of antigravity places in the lab to see how volunteers would react. As a conclusion, researchers from Universities of Padova and Pavia in Italy found that without a true horizon in sight, landmarks such as trees and signs actually played these tricks on the human brain.

The illusion is similar to the Ames room, in which objects can also appear to roll against gravity.

The opposite phenomenon—an uphill road that appears flat—is known in bicycle racing as a "false flat".

🔗 Books 🔗 Middle Ages 🔗 Middle Ages/History 🔗 Visual arts

The Black Hours, MS M.493 (or the Morgan Black Hours) is an illuminated book of hours completed in Bruges between 1460 and 1475. It consists of 121 pages (leaves), with Latin text written in Gothic minuscule script. The words are arranged in rows of fourteen lines and follow the Roman version of the texts. The lettering is inscribed in silver and gold and placed within borders ornamented with flowers, foliage and grotesques, on pages dyed a deep blueish black. It contains fourteen full-page miniatures and opens with the months of the liturgical calendar (folios 3 verso – 14 recto), followed by the Hours of the Virgin, and ends with the Office of the Dead (folio 121v).

MS M.493 has been in the collection of the Morgan Library & Museum, New York, since 1912. It is one of seven surviving black books of hours, all originating from Bruges and dated to the mid-to-late 15th century. They are so named for their unusual dark blueish appearance, a colourisation achieved through the expensive process of dyeing the vellum with iron gall ink. This dye is very corrosive and the surviving examples are mostly badly decomposed; MS M.493 is in relatively good condition due to its very thick parchment.

The book is a masterpiece of Late Gothic manuscript illumination. However, no records survive of its commission, but its uniquely dark tone, expense of production, quality and rarity suggest ownership by privileged and sophisticated members of the Burgundian court. The book is often attributed, on stylistic grounds, to a follower of Willem Vrelant, a leading and influential Flemish illuminator.

🔗 Lists 🔗 Libraries

This is a list of other articles that are lists of list articles on the English Wikipedia. In other words, each of the articles linked here is an index to multiple lists on a topic. Some of the linked articles are themselves lists of lists of lists. This article is also a list of lists, and also a list itself.

🔗 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.

🔗 Books 🔗 Women's History

Around the World in Seventy-Two Days is an 1890 book by journalist Elizabeth Jane Cochrane, writing under her pseudonym, Nellie Bly. The chronicle details her 72-day trip around the world, which was inspired by the book, Around the World in Eighty Days by Jules Verne. She carried out the journey for Joseph Pulitzer's tabloid newspaper, the New York World.

🔗 Urban studies and planning

The Lewis–Mogridge position, named after David Lewis and Martin J. H. Mogridge, was formulated in 1990 and observes that as more roads are built, more traffic consequently fills these roads. Speed gains from some new roads can disappear within months, if not weeks. Sometimes, new roads help to reduce traffic jams, but in most cases, the congestion is only shifted to another junction.

The position reads traffic expands to meet the available road space (Mogridge, 1990). It is generally referred to as induced demand in the transport literature, and was posited as the "Iron Law of Congestion" by Anthony Downs. It is a special case of Jevons paradox (where the resource in question is traffic capacity), and relates to the Marchetti's constant (average commute times are similar in widely varying conditions).

Following the position, it is not generally concluded that new roads are never justified but that their development needs to consider the whole traffic system, which means understanding the movement of goods and people in detail as well as the motivation behind the movement.

The position is often used to understand problems caused by private transport such as congested roads in cities and on motorways. It can also be used to explain the success of schemes such as the London congestion charge.

The position, however, is not confined to private transport. Mogridge, a British transport researcher, concluded also that all road investment in a congested urban area will have the effect of reducing the average speed of the transport system as a whole: road and public transport. The relationship and overall equilibria are also known as the "Downs–Thomson paradox". However, according to Downs, the link between average speeds on public transport and private transport applies only "to regions in which the vast majority of peak-hour commuting is done on rapid transit systems with separate rights of way. Central London is an example, since in 2001 around 85 percent of all morning peak-period commuters into that area used public transit (including 77 percent on separate rights of way) and only 11 percent used private cars. When peak-hour travel equilibrium has been reached between the subway system and the major commuting roads, then the travel time required for any given trip is roughly equal on both modes."