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Khat

Khat or qat, Catha edulis (ጫት ch’at; Oromo: Jimaa, qaad, jaat, khaad or khat, القات al-qāt, Swahili: miraa, muguka, jaba, veve or aluta) is a flowering plant native to eastern and southeastern Africa. It has a history of cultivation originating in the Harar area (present day eastern Ethiopia) and subsequently introduced at different times to countries nearby in East Africa and Southern Arabia, most notably Yemen. Cultivated by farmers, its leaves are sold on the market to be chewed as a recreational stimulant. The world's largest consumers are Eastern Africans, particularly Somalis, and nearby Yemen; with the largest producers/exporters being Ethiopia and Kenya,

Khat contains the alkaloid cathinone, a stimulant which causes greater sociability, excitement, mild loss of appetite and mild euphoria. Among communities from the areas where the plant is native, khat-chewing has historical relevance (as a social custom, especially among men) dating back thousands of years, analogous—but slightly different—to the use of coca leaves in South America's Andes Mountains or the betel nut preparations in South Asia.

Since 1980, the World Health Organization (WHO) classifies khat as a “drug of abuse” that can produce psychological dependence, although the WHO does not consider khat addiction to be a serious global problem.

The legality of khat varies by region and country; in many territories, khat might pass “under-the-radar” as a botanical species (thus not be a specifically controlled substance), but its recreational use may, nevertheless, be illegal under more general laws. It is strictly a controlled substance in many regions, often at the highest degree, including in Australia, Canada, the European Union, India, Jordan, New Zealand, Saudi Arabia, the United Arab Emirates (UAE) and the United Kingdom (UK). In the United States (US) and Turkey, the botanical specimen (plant) Catha edulis is not outrightly banned, but the consumption and distribution of harvested leaves or possession for recreational use is illegal in some countries. In the UAE, the punishment for possession, use, or distribution of khat can include life imprisonment. By contrast, its production, sale, and consumption are all fully legal—or not mentioned in a legal context at all—in the nations where its use is culturally significant, including Djibouti, Ethiopia, Kenya, Somalia, Sudan, Uganda and Yemen. In Israel, which hosts a population of Yemenite Jews, only the consumption of the plant's leaves in its natural state is permitted, “khat extract” are illegal, because they became a street drug and were popularly abused in the 2000s.

Nomenclature
The genus name Catha is a Latinization of the Arabic name قات, which is regularly romanized as qāt. Other romanizations include kat, quatt, qaad, qhat, ghat, and chat.

The khat plant is known by a variety of names, such as qat and gat in Yemeni Arabic, qaat and jaad in Somali, and chat in Harari and Amharic. It is also known as jimaa in the Oromo language, mayirungi in Luganda, and as miraa in Swahili. In the African Great Lakes region, where Catha edulis is (in some areas) cultivated, it is known as miraa, muhulo, muguka and muirungi.

It also goes by various descriptive names, such as Abyssinian tea, Arabian tea, kafta, jimaa, and Somalian tea in its endemic regions of the Horn of Africa and the Arabian peninsula. In South Africa, the plant is known as bushman's tea. The plant is also known as chat tree and flower of paradise.

Description

Khat is a slow-growing shrub or tree that typically attains a height of 1-5 m. However, it can reach heights of up to 10 m in equatorial areas. The plant usually grows in arid environments, at a temperature range of 5 - 35 C. It has evergreen leaves, which are 5–10 cm long and 1-4 cm broad.

It takes seven to eight years for the khat plant to reach its full height. Other than access to sun and water, khat requires little maintenance. Ground water is often pumped from deep wells by diesel engines to irrigate the crops, or brought in by water trucks. The plants are watered heavily starting around a month before they are harvested to make the leaves and stems soft and moist. A good khat plant can be harvested four times a year, providing a year-long source of income for the farmer.

The shrub's flowers are produced on short axillary cymes that are 4-8 cm in length. Each flower is small, with five white petals.

The samara fruit is an oblong, three-valved capsule, which contains one to three seeds.

Cultivation and uses
Khat has been grown for use as a stimulant for centuries in the Horn of Africa and the Arabian peninsula. There, chewing khat predates the use of coffee and is used in a similar social context. Its fresh leaves and tops are chewed or, less frequently, dried and consumed as tea, to achieve a state of euphoria and stimulation. The leaves or the soft part of the stem can be chewed with either chewing gum or fried peanuts to make it easier to chew.

In Uganda, it is grown in the central region, especially in Kasenge (Wakiso), Butambala District, Mabira Forest, and in some parts of the western region of the country. In Kenya, it is grown in Meru County and Embu County.

Although the practice of khat-chewing is still primarily restricted to its original area of cultivation in the Red Sea area, the khat plant has, over the years, found its way to southern Africa as well as tropical areas, where it grows on rocky outcrops and in woodlands. The shrub is, today, scattered but still found wild in the KwaZulu-Natal, Eastern Cape, Western Cape and Mpumalanga provinces of South Africa, in addition to Eswatini and Mozambique. In recent years, however, improved roads, off-road motor vehicles, and air transportation have increased the global distribution of this perishable commodity and, as a result, the plant has been found in places such Australia, Amsterdam, Canada, England, the Levant, Rome (Italy), New Zealand, and Wales. and the United States. In the US, freshly-packed khat leaves are sold in the African and Middle Eastern markets of Boston, Dallas, Los Angeles, and New York City, where the demand is highest.

Traditionally, khat is used as a socialising drug as in Yemen, where khat-chewing is predominantly a male habit combined with conversation, hookah smoking, and tea drinking. Khat is so popular in Yemen that its cultivation consumes much of the country's agricultural resources. An estimated 40% of Yemen's water supply goes towards irrigating it, with production increasing by about 10% to 15% every year. One "daily bag" of khat requires an estimated 500 L of water to produce. Water consumption is high and groundwater levels in the Sana'a basin are diminishing, so government officials have proposed relocating large portions of the population of the city to the Red Sea coastal areas.

One reason for the widespread cultivation of khat in Yemen is the high income that it provides for farmers. Some studies done in 2001 estimated that the income from cultivating khat was about 2.5 million Yemeni rials per hectare, while fruits brought only 0.57 million rials per hectare. Between 1970 and 2000, the area on which khat was cultivated was estimated to have grown from 8,000 to 103,000 hectares. In 2000, according to a World Bank estimate, khat accounted for 30% of Yemen's economy.

In countries outside the core area of growth and consumption, khat is sometimes chewed at parties or social functions. It may also be used by farmers and labourers for reducing physical fatigue or hunger, and by drivers and students for improving attention.

More recently, in 2019, reports indicate that child soldiers in Yemen have been chewing khat in order to remain alert on the battlefield.

Effects
Khat consumption induces mild euphoria and excitement, similar to that conferred by strong coffee. Individuals become very talkative under the influence of the plant. Animal testing has shown that khat causes an increase in motoric activity. The effects of oral administration of cathinone occur more rapidly than the effects of amphetamine pills; roughly 15 minutes as compared to 30 minutes in amphetamine. Khat can induce manic behaviours and hyperactivity, similar in effects to those produced by amphetamine.

The use of khat results in constipation. Dilated pupils (mydriasis) are prominent during khat consumption, reflecting the sympathomimetic effects of the drug, which are also reflected in increased heart rate and blood pressure. Long-term use can precipitate permanent tooth darkening (of a greenish tinge), susceptibility to ulcers, and diminished sex drive. Khat is an effective anorectic, causing loss of appetite.

It is unclear if the consumption of khat directly affects the mental health of the user or not. Occasionally, a psychotic episode can result, resembling a hypomanic state in presentation. In humans, its prolonged consumption creates an uplifted mood and a sense of release from time and space.

Khat is mainly chewed by men, but there are cases of its use by women, and in particular it has been associated with increased likelihood of adverse outcomes during pregnancy.

Effects by timeframe
Immediate
 * alertness
 * arousal
 * concentration
 * confidence
 * constipation
 * dilated pupils
 * euphoria
 * friendliness
 * increased blood pressure
 * increased heart rate
 * insomnia
 * mania
 * psychosis
 * suppressed appetite
 * talkativeness
 * thought disorder
 * verbosity

Long-term
 * depression
 * infrequent hallucinations
 * impaired inhibition (similar to alcohol)
 * increased risk of myocardial infarction (heart attack)
 * oral cancer
 * psychosis in extreme cases in the genetically predisposed
 * weight loss

Indeterminate
 * death
 * stroke following acute coronary syndrome (clogging of the artery)

Chemistry and pharmacology
The stimulant effect of the plant was originally attributed to "katin", cathine, a phenethylamine-type substance isolated from the plant. However, the attribution was disputed by reports showing the plant extracts from fresh leaves contained another substance more behaviourally active than cathine. In 1975, the related alkaloid cathinone was isolated, and its absolute configuration, (S)-2-Amino-1-phenylpropan-1-one, was established in 1978. Cathinone is not very stable and breaks down to produce cathine and norephedrine. These chemicals belong to the PPA (phenylpropanolamine) family, a subset of the phenethylamines related to amphetamines and the catecholamines epinephrine and norepinephrine. In fact, cathinone and cathine have a very similar molecular structure to amphetamine. Khat is sometimes confused with methcathinone (also known as cat), a Schedule I substance that possesses a similar chemical structure to the khat plant's cathinone active component. However, both the side effects and the addictive properties of methcathinone are much stronger than those associated with khat use.

When khat leaves dry, the more potent chemical, cathinone, decomposes within 48 hours, leaving behind the milder chemical, cathine. Thus, harvesters transport khat by packaging the fresh leaves and stems in plastic bags or wrapping them in banana leaves to preserve their moisture and keep the cathinone potent. It is also common for them to sprinkle the plant with water frequently or use refrigeration during transportation.

When the khat leaves are chewed, cathine and cathinone are released and absorbed through the mucous membranes of the mouth as well as the lining of the stomach. The action of cathine and cathinone on the reuptake of epinephrine and norepinephrine has been demonstrated in lab animals, showing that one or both of these chemicals cause(s) the body to recycle these neurotransmitters more slowly, resulting in the wakefulness and insomnia associated with khat use.

Receptors for serotonin show a high affinity for cathinone, suggesting this chemical is responsible for feelings of euphoria associated with chewing khat. In mice, cathinone produces the same types of nervous pacing or repetitive scratching behaviours associated with amphetamines. The effects of cathinone peak after 15 to 30 minutes, with nearly 98% of the substance metabolised into norephedrine by the liver.

Cathine is somewhat less understood, being believed to act upon the adrenergic receptors causing the release of epinephrine and norepinephrine. It has a half-life of about three hours in humans. The medication bromocriptine can reduce cravings and withdrawal symptoms within 24 hours.

Demographics
An estimated 5 to 10 million people globally use khat on a daily basis. It is grown principally by communities in the Horn of Africa and the Arabian peninsula, where khat-chewing has a long history as a social custom dating back thousands of years.

The traditional form of khat chewing in Yemen involves only male users; khat chewing by females is less formal and less frequent. Researchers estimate about 70–80% of Yemenis between 16 and 50 years old chew khat, at least on occasion. Approximately 60–90% of male and 35% of female Yemenis chew khat daily. Before Yemeni unification in 1990, khat chewing was largely confined to the north-west mountains of the country, where khat grows. Yemenis spend an estimated 14.6 million man-hours per day chewing khat. Researchers have also estimated that families spend about 17% of their income on khat.

History

The inhabitants of Ifat Sultanate were the first to be recorded using khat in the 14th century by Arab historian Ibn Fadlallah al-Umari. The khat plant likely originated in the Horn of Africa specifically Ethiopia-Somali area, from there it spread to Kenya and the Arabian Peninsula. According to nineteenth century British explorer Richard Burton, khat originated in the Emirate of Harar.

Muslim Sufis in the surrounding areas also used it to intensify their mystical experience and to facilitate a sense of union with God.

The earliest known documented description of khat is found in the Kitab al-Saidala fi al-Tibb كتاب الصيدلة في الطب, an 11th-century work on pharmacy and materia medica written by Abū Rayhān al-Bīrūnī, a Persian scientist and biologist. Unaware of its origins, al-Bīrūnī wrote that khat is:

"[A] commodity from Turkestan. It is sour to taste and slenderly made in the manner of batan-alu. But khat is reddish with a slight blackish tinge. It is believed that batan-alu is red, coolant, relieves biliousness, and is a refrigerant for the stomach and the liver."

It is mentioned again in a 13th-century publication by the physician Naguib Ad-Din.

In 1854, Malay author Abdullah bin Abdul Kadir noted that the custom of chewing khat was prevalent in Al Hudaydah in Yemen:

"You observed a new peculiarity in this city – everyone chewed leaves as goats chew the cud. There is a type of leaf, rather wide and about two fingers in length, which is widely sold, as people would consume these leaves just as they are; unlike betel leaves, which need certain condiments to go with them, these leaves were just stuffed fully into the mouth and munched. Thus when people gathered around, the remnants from these leaves would pile up in front of them. When they spat, their saliva was green. I then queried them on this matter: ‘What benefits are there to be gained from eating these leaves?’ To which they replied, ‘None whatsoever, it’s just another expense for us as we’ve grown accustomed to it’. Those who consume these leaves have to eat lots of ghee and honey, for they would fall ill otherwise. The leaves are known as Kad.'"

In 1856, English writer Charles Dickens also described the custom of khat chewing in the Horn region and the adjacent Gulf territories, likening it to drinking strong green tea:

"And one may sleep well if, during the day, too much kat has not been chewed. The leaves of the drug called kat are the chief source of pleasurable excitement in these districts of East Africa. Botanists, taking the native name for the plant, turn it into Catha edulis, eatable kat. It is much used by the Arabs, to whom it is sent in camel loads, consisting of a number of small parcels, each containing about forty slender twigs, with the leaves attached, carefully, wrapped so as to avoid exposure to the air. These leaves are chewed, and act upon the spirits of those using them, much as a strong dose of green tea acts upon us in Europe, when it acts agreeably. Europeans used to stronger stimulants, are little affected by the use of kat, but among the more temperate Arabs it is so welcome a provocative to good humour, that about two hundred and eighty camel-loads of it are used every year in Aden only."

Nowadays khat consumption is limited to East Africa and South Western Arabia. These countries include Djibouti, Ethiopia, Kenya, Somalia (includes Somaliland), Uganda, and Yemen. The author Yousif Al Zarouni writes in his book:

"The plant is native to the Arabian Peninsula and the Horn of Africa, despite its native grounds it is only legal in one of the several countries of the Arabian Peninsula, Yemen. The plant however is widely available and legal in East Africa, some African nations on the other hand such as South Africa consider it as a protected species.

The plant is mostly used by East Africans and South West Arabians, rarely by people from other places."

Following a ban on khat in the British-governed Aden Protectorate, the Qāt Commission of Inquiry in Aden concluded: "Qāt does not create an addiction, like opium or hashish, in that those who are suddenly deprived of it, do not suffer physical consequences."

Regulation
In 1965, the World Health Organization (WHO) Expert Committee on Dependence-producing Drugs' Fourteenth Report noted, "The Committee was pleased to note the resolution of the Economic and Social Council with respect to khat, confirming the view that the abuse of this substance is a regional problem and may best be controlled at that level." For this reason, khat was not scheduled under the Single Convention on Narcotic Drugs. In 1980, the WHO classified the plant as a drug of abuse that can produce mild to moderate psychological dependence (less than tobacco or alcohol), although the WHO does not consider khat to be seriously addictive. It is a controlled or illegal substance in some countries, but is legal for sale and production in others.

Morocco
Khat is illegal in Morocco.

Ethiopia
Khat is legal in Ethiopia.

Somalia
Khat is legal in Somalia.

Djibouti
Khat is legal in Djibouti.

Kenya
Khat is legal in Kenya. However, two of its active components, cathinone and cathine, are classed as Class C substances.

South Africa
In South Africa, Catha edulis is a protected tree.

The use of khat is illegal.

Uganda
Miraa is legal in Uganda but efforts are underway (as of October 2015) to ban it. Khat has now been banned in Uganda.

Bangladesh
Khat is illegal in Bangladesh.

China
Khat is illegal in China.

Hong Kong
Khat is regarded as a dangerous drug in Hong Kong. Traffickers can face a penalty up to HK$5 million as well as life imprisonment.

Taiwan
In Taiwan, khat is illegal. It is classified as a narcotic drug.

Israel
Khat, called "Gat" in Israel, is consumed mainly by Yemenite Jews and Beta Israel. The activity of chewing its leaves is called "lekhazen" (לכזן). The process of chewing the Gat can take up to several hours. Some chew the Gat in a gathering which is called "takhazina" (תכזינה). The Gat is grown traditionally in private gardens, but it may be found in some markets.

Gat is legal in Israel as long as it is consumed in its natural form, but the distillation of its components is illegal. Some use the plant as a hedge since it is an evergreen.

In 2003, Hagigat, a pill based on extracted cathinone, began to be sold in kiosks in Israel. Following several cases of hospitalisation, the Israeli Ministry of Health classified cathinone as a dangerous drug, and Hagigat was outlawed. The plant itself is allowed to be chewed and sold in its natural state, as no harm was found in normal quantities.

As of June 2012, the Israeli anti-drug authority announced that beverages containing Khat are considered illegal as per the dangerous drug ordinance of the state of Israel.

Indonesia
Khat is illegal in Indonesia.

Saudi Arabia
Khat is illegal in Saudi Arabia.

Singapore
Khat is prohibited in Singapore by the Central Narcotics Bureau (CNB).

United Arab Emirates
Khat is illegal in the United Arab Emirates under federal law number 14 of 1995 on the Countermeasures against Narcotic Drugs and Psychotropic Substances. Schedule No. 4, Part 2(5), provides for the prohibition of the cultivation and possession of khat. The possession and selling of khat may lead to life imprisonment.

Vietnam
Khat is classified as a narcotic drug in Vietnam. The illegal cultivation, possession and distribution of khat are criminally prosecuted. The use of khat may lead to mandatory rehabilitation.

Yemen
Khat is legal in Yemen. However, cultivation of the crop and the selling of its leaves are governed by a series of regulations. In 2007, the Yemeni government passed a law that restricted the cultivation of khat in a number of agricultural flatlands and basins with high water stress. The Law Concerning the General Sales Tax in 2005 also set the tax rate on khat at 20% of its retail price.

The widespread cultivation of khat in Yemen has exacerbated a severe water shortage. Khat is much more water-intensive to grow than other crops. It has also played a major role in a famine in the country.

Belgium
Khat has been illegal in Belgium since 2006.

Denmark
Khat has been illegal in Denmark since 1993. In 2009, the Danish Health Authority investigated khat use among Somalis in Denmark. A questionnaire with 848 respondents was used. The responses indicated that 48% of Somali males and 16% of females used the narcotic on a monthly basis and that 29% of males and 6% of females used it two times or more a week. Half the respondents had never used khat. The responses indicated that Somalis constituted the great majority of users in Denmark.

The report also investigated attitudes towards khat use among Somalis in Denmark. In total, two out of three respondents stated that khat is a problem for social integration into Danish society, while one in three users stated the same. Responses indicated that two out of three considered khat to be part of Somali culture, although two in three also stated that they agree that khat should be banned in Denmark.

Finland
Khat is classified as an illegal drug in Finland, and possession, use and sale of the substance is prohibited and punishable. As with all illegal drugs, operating a motor vehicle with detectable levels of Khat or its metabolites in one's system can also lead to a conviction for driving under the influence, even if the driver does not appear intoxicated.

France
Khat is prohibited in France as a stimulant since 1957.

Germany
In Germany, cathinone is listed as a "non-trafficable substance", which makes the possession, sale and purchase of fresh khat illegal. The derivative cathine, with "norpseudoephedrine" listed as an alternate name, is only available on prescription.

In 2017, 5815 kg of khat was discovered by customs officials in Frankfurt. In June 2018, 324 kg of khat was discovered in packages from East Africa.

Iceland
In August 2010 the Icelandic police intercepted khat smuggling for the first time. 37 kg were confiscated. The drugs were most likely intended for sale in Canada. Again in May 2011 the police intercepted around 60 kg.

Ireland
Khat is a controlled drug for the purpose of the Misuse of Drugs Act 1977 and Schedule 1 of the Misuse of Drugs Regulations 1988. As such its possession and supply is prohibited.

Italy
Khat is inserted in the Table I of the Italian official list of psychoactive drugs under the name "Catha edulis pianta" (English: "Catha edulis plant") and thus possession is forbidden.

Netherlands
In the Netherlands, the active ingredients of khat, cathine and cathinone, are qualified as hard drugs and forbidden. Use is mostly limited to the Somali community. In 2008 health minister Ab Klink decided against qualifying the unprocessed plant as drugs after consultation with experts. However, on 9 January 2012 the Dutch government announced a ban on khat.

Norway
In Norway, khat is classified as a narcotic drug and is illegal to use, sell and possess. Most users are Somali immigrants and khat is smuggled from the Netherlands and the United Kingdom.

Norwegian Customs seized 10 metric tons of khat in 2010, an increase from less than 4 in 2006.

In 2016, Oslo municipality estimated 50–70% of Somali immigrant males to be habitual users.

Poland
In Poland, khat is a classified narcotic drug, and is illegal to use, sell and possess.

Slovenia
Khat is classified as an illegal drug in Slovenia.

Sweden
The drug was prohibited in Sweden in 1989, without research. In 2007, it was estimated that 30% of Somali males in Sweden were using khat. Smuggling seizures by police amounted to about 9 tonnes annually.

Switzerland
In Switzerland, khat is illegal. It is classified as a narcotic drug.

United Kingdom
Khat was made illegal in the UK on 24 June 2014. Concerns had been expressed by commentators, health professionals and community members about the use of khat in the UK, particularly by immigrants from Somalia, Yemen and Ethiopia. Studies of the effects of khat use by immigrants on their mental health suggested that there was a need for better research on khat-chewing and its possible link with psychiatric disorders; it also suggested that public discourse on the issue displayed elements of a moral panic. Some Somali community organisations also campaigned for khat to be banned. As a result of these concerns, the Home Office commissioned successive research studies to look into the matter, and in 2005, presented the question of khat's legal status before the Advisory Council on the Misuse of Drugs. The study concluded that most of the participants who were using khat were using it moderately in terms of both the quantity used and the frequency and duration of chewing sessions, and that khat use was typically a social activity. Only a small minority of the study participants' khat use was judged to be excessive. After a careful review of the evidence, the Advisory Council on the Misuse of Drugs recommended in January 2006 that the status of khat as a legal substance should remain for the time being.

In 2008, Conservative politician Sayeeda Warsi stated that a future Conservative government would ban khat. The website of the Conservative Party, which in 2010 became the larger party in a UK coalition government, previously stated that a Conservative government would "Tackle unacceptable cultural practices by", amongst other measures, "classifying Khat". In 2009, the Home Office commissioned two new studies in the effects of khat use and in June 2010, a Home Office spokesperson stated: "The Government is committed to addressing any form of substance misuse and will keep the issue of khat use under close scrutiny".

During a parliamentary debate on the legality issue on 11 January 2012, Mark Lancaster, the Conservative Member of Parliament for Milton Keynes, stated that the importation of Khat into the UK stands at 10 tonnes every week.

On 23 January 2013, the Advisory Council on the Misuse of Drugs (ACMD) said there was "insufficient evidence" that khat caused health problems. The ACMD said there was "no evidence" khat was directly linked with serious or organised crime, and was chewed to obtain a "mild stimulant effect much less potent than stimulant drugs, such as amphetamine".

On 3 July 2013, the British Home Secretary Theresa May announced that khat was to be banned in Britain, designating it a Class C substance under the Misuse of Drugs Act 1971.

Alex Miller, a journalist from the Montreal, Canada-based magazine and television channel Vice, looked into the use of the substance and the potential impact of the ban for BBC nightly current affairs programme Newsnight and for a Vice documentary.

Kenyan MPs appealed to the UK not to "condemn people" by banning the herbal stimulant khat

In March 2014, the United Kingdom House of Commons' Home Affairs Select Committee announced that it would continue to lobby for the UK government not to go through with its intended ban on khat. The committee had shortly before also completed an inquiry and a report recommending that the British authorities refrain from banning the plant.

On 12 May 2014, the House of Lords passed a Motion to Approve the Misuse of Drugs Act 1971 (Designation)(Amendment) (No. 2)(England, Wales and Scotland) Order 2014, in order to control Catha edulis as a Class C drug. An amendment was proposed stating that, "this House regrets that Her Majesty’s Government’s plans for the introduction of the Order do not include provisions for a 12-month review of the impact of the reclassification of khat in view of the highly unusual community focus of its use, for putting a detailed policing strategy in place before a ban takes effect, or for a health strategy to prevent a transfer of addiction to other substances; and do not commit the Department for International Development to do more work with the government of Kenya to alleviate the effect of the reclassification on the Kenyan economy." However, the amendment was defeated by vote. The prohibition came into effect on 24 June 2014.

In January 2015, the Bristol Post reported that most khat houses in the city had closed down, "forcing users to take the drug in their homes instead". The local police had initially not sought to enforce the ban, giving users a grace period, but according to the Bristol Post had recently started to take action against khat use and had issued three warnings and a caution. Additionally, in September 2014 the police had seized 24 bags of dried khat from a property in Easton, but no arrests were made. Additionally, the Somali Resource Centre indicated that the ban seemed to have been effective, and that the prohibition had all but destroyed the import market since the plant has to be fresh in order to be consumed. A consultation with Somalis in Glasgow undertaken by the national voluntary organisation Fast Forward at the request of the Somali Association in Glasgow in October 2014 suggested that khat continues to be used in both fresh and dried forms by some Somalis in the city, and that the ban has also led some users to seek out other substances. The ban has reportedly served to increase the price of khat in the UK. Channel 4 News reported in September 2014 that before the ban, 20 tonnes of khat arrived at Heathrow Airport daily, and it would sell for £3 per bundle. After the ban, it was reportedly selling at £30 per bundle.

Canada
In Canada, khat is a controlled substance under Schedule IV of the Controlled Drugs and Substances Act (CDSA), meaning it is illegal to seek or obtain unless approved by a medical practitioner. Possession of khat for personal use is not an arraignable offence in Canada. The maximum punishment for trafficking or possession with the intent of trafficking is ten years in prison.

In 2008, Canadian authorities reported that khat is the most common illegal drug being smuggled at airports.

However, in 2012 the Ontario Court of Appeal upheld a 2011 absolute discharge of a young woman who brought 34 kilograms of khat into Canada in 2009. According to the defence, the ruling recognises that there is no empirical evidence that khat is harmful. The courts in Quebec and Ontario continued to discharge the accused for bringing khat into Canada for the same reason (no evidence of harmfulness of khat) in 2014 and 2016.

United States
In the United States, cathinone is a Schedule I drug, according to the US Controlled Substance Act. The 1993 DEA rule placing cathinone in Schedule I noted that it was effectively also banning khat:

"'Cathinone is the major psychoactive component of the plant Catha edulis (khat). The young leaves of khat are chewed for a stimulant effect. Enactment of this rule results in the placement of any material that contains cathinone into Schedule I.'"

Catha edulis (khat) is a stimulant similar to that of amphetamine and its congeners, not a drug as categorised by US FDA (United States Food & Drug Administration) and FDA import Alert #66-23 (published date 03/18/2011) states that "Districts may detain, without physical examination, all entries of khat", based on section 801(a) (3) of the Federal Food, Drug, and Cosmetic Act on the grounds that "its labeling fails to bear adequate directions for use."

As federal and local khat raids have often targeted immigrants from countries where khat is legal, issues of cultural misunderstanding have sometimes been raised.

The plant itself is specifically banned in Missouri: "'Khat, to include all parts of the plant presently classified botanically as catha edulis, whether growing or not; the seeds thereof; any extract from any part of such plant; and every compound, manufacture, salt, derivative, mixture, or preparation of the plant, its seed or extracts.'"

In California, both the plant itself as well as cathinone, its active component, are illegal.

Australia
In Australia, the importation of khat is controlled under the Customs (Prohibited Imports) Regulations 1956. It is illegal to import khat into Australia for personal use. Khat can be imported only for medical or scientific use.

Importing khat without a permit is subject to fines or prosecution. In 2003, the total number of khat annual permits was 294 and the total number of individual khat permits was 202 however as of 1 December 2013, permits for the use of khat by individuals for recreational/cultural purposes are no longer issued. There are currently no plans by the Australian Government to amend the regulations to allow the importation of khat for personal use.

Khat is listed as a Schedule 2 dangerous drug in Queensland, in the same category as cannabis. Legality in New South Wales is not clear.

The importation of Khat (Catha edulis) material (includes material that is fresh, dried, powdered, capsules or tablets) is prohibited under the Customs (Prohibited Import) Regulations 1956 unless the person importing the material is the holder of both a license to import and a permit to import granted by the Therapeutic Goods Administration (TGA). Biosecurity Act 2015

New Zealand
In New Zealand, khat is listed as a Class C drug, in the same category as cannabis and codeine.

South America
In South America, there is no legislation regarding khat; the active ingredients in the plant can be found in several weight control compounds sold in the continent.

Research programs
In 2009, the University of Minnesota launched the Khat Research Program (KRP), a multidisciplinary research and training program focusing on the neurobehavioral and health effects of khat, led by Prof. Dr. Mustafa al'Absi. The program was funded by the National Institutes of Health and the National Institute for Drug Abuse of the United States. The inaugural event for the KRP was held in Sharm El-Sheik, Egypt, in December, 2009 in collaboration with the International Brain Research Organization (IBRO) and its local affiliates.

title: Khat


text:
Qat

Qat may refer to:

 * Qaumi Awami Tahreek a Political party in Pakistan
 * Khat or qat, a flowering plant
 * Qat (deity), a deity of northern Vanuatu
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Necromancy

Necromancy  is the practice of magic involving communication with the dead by summoning their spirits as apparitions or visions for the purpose of divination; imparting the means to foretell future events and discover hidden knowledge. Sometimes categorized under death magic, the term is occasionally also used in a more general sense to refer to black magic or witchcraft as a whole.

Etymology
The word necromancy is adapted from Late Latin necromantia: a loan word from the post-Classical Greek νεκρομαντεία (nekromanteía, or 'divination through a dead body'), a compound of Ancient Greek νεκρός (nekrós, or 'dead body') and μαντεία (manteía, or 'divination').

The Koine Greek compound form was first documented in the writings of Origen of Alexandria in the 3rd century AD. The Classical Greek term was ἡ νέκυια (nekyia), from the episode of the Odyssey in which Odysseus visits the realm of the dead souls, and νεκρομαντεία in Hellenistic Greek; necromantīa in Latin, and necromancy in 17th-century English.

Antiquity
Early necromancy was related to – and most likely evolved from –forms of shamanism or prehistoric ritual magic that calls upon spirits such as the ghosts of deceased forebears. Classical necromancers addressed the dead in "a mixture of high-pitch squeaking and low droning", comparable to the trance-state mutterings of shamans. Necromancy was prevalent throughout antiquity with records of its practice in ancient Egypt, Babylonia, Greece, ancient Etruria, Rome, and China. In his Geographica, Strabo refers to νεκρομαντία (nekromantia), or "diviners by the dead", as the foremost practitioners of divination among the people of Persia, and it is believed to have also been widespread among the peoples of Chaldea (particularly the Hermeticists, or "star-worshipers") and Babylonia. The Babylonian necromancers were called manzazuu or sha'etemmu, and the spirits they raised were called etemmu. Traditional Chinese folk religion involves necromancy in seeking blessing from dead ancestors through ritual displays of filial piety.

The oldest literary account of necromancy is found in Homer's Odyssey. Under the direction of Circe, a powerful sorceress, Odysseus travels to the underworld (katabasis) in order to gain insight about his impending voyage home by raising the spirits of the dead through the use of spells which Circe has taught him. He wishes to invoke and question the shade of Tiresias in particular; however, he is unable to summon the seer's spirit without the assistance of others. The Odyssey's passages contain many descriptive references to necromantic rituals: rites must be performed around a pit with fire during nocturnal hours, and Odysseus has to follow a specific recipe, which includes the blood of sacrificial animals, to concoct a libation for the ghosts to drink while he recites prayers to both the ghosts and gods of the underworld.

Practices such as these, varying from the mundane to the grotesque, were commonly associated with necromancy. Rituals could be quite elaborate, involving magic circles, wands, talismans, and incantations. The necromancer might also surround himself with morbid aspects of death, which often included wearing the deceased's clothing and consuming foods that symbolized lifelessness and decay such as unleavened black bread and unfermented grape juice. Some necromancers even went so far as to take part in the mutilation and consumption of corpses. These ceremonies could carry on for hours, days, or even weeks, leading up to the eventual summoning of spirits. Frequently they were performed in places of interment or other melancholy venues that suited specific guidelines of the necromancer. Additionally, necromancers preferred to summon the recently departed based on the premise that their revelations were spoken more clearly. This timeframe was usually limited to the twelve months following the death of the physical body; once this period elapsed, necromancers would evoke the deceased's ghostly spirit instead.

While some cultures considered the knowledge of the dead to be unlimited, ancient Greeks and Romans believed that individual shades knew only certain things. The apparent value of their counsel may have been based on things they knew in life or knowledge they acquired after death. Ovid writes in his Metamorphoses of a marketplace in the underworld where the dead convene to exchange news and gossip.

Prohibited among Israelites
There are also several references to necromancers – called "bone-conjurers" among Jews of the later Hellenistic period – in the Bible. The Book of Deuteronomy (18:9–12 ) explicitly warns the Israelites against engaging in the Canaanite practice of divination from the dead: "9When thou art come into the land which the LORD thy God giveth thee, thou shalt not learn to do according to the abominations of those nations. 10There shall not be found among you any one who maketh his son or his daughter to pass through the fire, or who useth divination, or an observer of times, or an enchanter, or a witch, 11or a charmer, or a consulter with familiar spirits, or a wizard, or a necromancer. 12For all who do these things are an abomination unto the LORD, and because of these abominations the LORD thy God doth drive them out from before thee (KJV)." Though Mosaic Law prescribed the death penalty to practitioners of necromancy (Leviticus 20:27 ), this warning was not always heeded. One of the foremost examples is when King Saul had the Witch of Endor invoke the spirit of Samuel, a judge and prophet, from Sheol to divine the outcome of a coming battle (1 Samuel 28:3–25 ). However, the so-called witch was shocked at the presence of a familiar spirit in the image of Samuel for in I Sam 28:7 states "Behold, there is a woman that hath a familiar spirit at Endor" and in I Sam 28:12 says, "when the woman saw Samuel, she cried out in a loud voice." and the familiar spirit questioned his reawakening asking as if he were Samuel the Prophet, "Why hast thou disquieted me?" Saul died the next day in combat, with Chronicles 10:13 implying this was due to the prohibition against necromancy.

Early and High Middle Age
Many medieval writers believed that actual resurrection required the assistance of God. They saw the practice of necromancy as conjuring demons who took the appearance of spirits. The practice became known explicitly as maleficium, and the Catholic Church condemned it. Though the practitioners of necromancy were linked by many common threads, there is no evidence that these necromancers ever organized as a group. One noted commonality among practitioners of necromancy was usually the utilization of certain toxic and hallucinogenic plants from the nightshade family such as black henbane, jimson weed, belladonna or mandrake, usually in magic salves or potions.

Medieval necromancy is believed to be a synthesis of astral magic derived from Arabic influences and exorcism derived from Christian and Jewish teachings. Arabic influences are evident in rituals that involve moon phases, sun placement, day and time. Fumigation and the act of burying images are also found in both astral magic and necromancy. Christian and Jewish influences appear in the symbols and in the conjuration formulas used in summoning rituals.

Practitioners were often members of the Christian clergy, though some nonclerical practitioners are recorded. In some instances, mere apprentices or those ordained to lower orders dabbled in the practice. They were connected by a belief in the manipulation of spiritual beings – especially demons – and magical practices. These practitioners were almost always literate and well educated. Most possessed basic knowledge of exorcism and had access to texts of astrology and of demonology. Clerical training was informal and university-based education rare. Most were trained under apprenticeships and were expected to have a basic knowledge of Latin, ritual and doctrine. This education was not always linked to spiritual guidance and seminaries were almost non-existent. This situation allowed some aspiring clerics to combine Christian rites with occult practices despite its condemnation in Christian doctrine.

Medieval practitioners believed they could accomplish three things with necromancy: will manipulation, illusions, and knowledge:
 * Will manipulation affects the mind and will of another person, animal, or spirit. Demons are summoned to cause various afflictions on others, "to drive them mad, to inflame them to love or hatred, to gain their favor, or to constrain them to do or not do some deed."
 * Illusions involve reanimation of the dead or conjuring food, entertainment, or a mode of transportation.
 * Knowledge is allegedly discovered when demons provide information about various things. This might involve identifying criminals, finding items, or revealing future events.

The act of performing medieval necromancy usually involved magic circles, conjurations, and sacrifices such as those shown in the Munich Manual of Demonic Magic:
 * Circles were usually traced on the ground, though cloth and parchment were sometimes used. Various objects, shapes, symbols, and letters may be drawn or placed within that represent a mixture of Christian and occult ideas. Circles were usually believed to empower and protect what was contained within, including protecting the necromancer from the conjured demons. A text known as the Heptameron explain the function of the circle thusly: "But because the greatest power is attributed to the Circles; (For they are certain fortresses to defend the operators safe from the evil Spirits;)..."
 * Conjuration is the method of communicating with the demons to have them enter the physical world. It usually employs the power of special words and stances to call out the demons and often incorporated the use of Christian prayers or biblical verses. These conjurations may be repeated in succession or repeated to different directions until the summoning is complete.
 * Sacrifice was the payment for summoning; though it may involve the flesh of a human being or animal, it could sometimes be as simple as offering a certain object. Instructions for obtaining these items were usually specific. The time, location, and method of gathering items for sacrifice could also play an important role in the ritual.

The rare confessions of those accused of necromancy suggest that there was a range of spell casting and related magical experimentation. It is difficult to determine if these details were due to their practices, as opposed to the whims of their interrogators. John of Salisbury is one of the first examples related by Richard Kieckhefer, but as a Parisian ecclesiastical court record of 1323 shows, a "group who were plotting to invoke the demon Berich from inside a circle made from strips of cat skin" were obviously participating in what the Church would define as "necromancy".

Herbert Stanley Redgrove claims necromancy as one of three chief branches of medieval ceremonial magic, alongside black magic and white magic. This does not correspond to contemporary classifications, which often conflate "nigromancy" ("black-knowledge") with "necromancy" ("death-knowledge").

Late Middle Ages to Renaissance
In the wake of inconsistencies of judgment, necromancers and other practitioners of the magic arts were able to utilize spells featuring holy names with impunity, as any biblical references in such rituals could be construed as prayers rather than spells. As a consequence, the necromancy that appears in the Munich Manual is an evolution of these theoretical understandings. It has been suggested that the authors of the Manual knowingly designed the book to be in discord with ecclesiastical law. The main recipe employed throughout the Manual used the same religious language and names of power alongside demonic names. An understanding of the names of God derived from apocryphal texts and the Hebrew Torah required that the author of such rites have at least a casual familiarity with these sources.

Within the tales related in occult manuals are found connections with stories from other cultures' literary traditions. For instance, the ceremony for conjuring a horse closely relates to the Arabic One Thousand and One Nights and French romances; Chaucer's The Squire's Tale also bears marked similarities. This becomes a parallel evolution of spells to foreign gods or demons that were once acceptable, and frames them into a new Christian context, albeit demonic and forbidden. As the material for these manuals was apparently derived from scholarly magical and religious texts from a variety of sources in many languages, the scholars who studied these texts likely manufactured their own aggregate sourcebook and manual with which to work spells or magic.

In the notebooks of Leonardo da Vinci, it is stated that "Of all human opinions that is to be reputed the most foolish which deals with the belief in Necromancy, the sister of Alchemy, which gives birth to simple and natural things."

Modern era
In the present day, necromancy is more generally used as a term to describe manipulation of death and the dead, or the pretense thereof, often facilitated through the use of ritual magic or some other kind of occult ceremony. Contemporary séances, channeling and Spiritualism verge on necromancy when supposedly invoked spirits are asked to reveal future events or secret information. Necromancy may also be presented as sciomancy, a branch of theurgic magic.

As to the practice of necromancy having endured in one form or another throughout the millennia, An Encyclopædia of Occultism states: "The art is of almost universal usage. Considerable difference of opinion exists among modern adepts as to the exact methods to be properly pursued in the necromantic art, and it must be borne in mind that necromancy, which in the Middle Ages was called sorcery, shades into modern spiritualistic practice. There is no doubt, however, that necromancy is the touch-stone of occultism, for if, after careful preparation the adept can carry through to a successful issue, the raising of the soul from the other world, he has proved the value of his art."

Contemporary pop-culture
The archvillain in J.R.R. Tolkien's Lord of the Rings fantasy, Sauron, first reappears in the environs of Middle Earth as 'the Necromancer of Dol Guldor' in Tolkien's standalone prologue to the trilogy the Hobbit. In fictional settings such as Dungeons & Dragons, or fantasy video games, necromancy is associated with the reanimation of corpses often meant to be used as weapons. This tradition appears to combine associations of conjuring the dead from European and Mediterranean traditions with elements involving Zombies that seem to derive from Caribbean folklore and practice.

title: Necromancy


text:
Root

In vascular plants, the roots are the organs of a plant that are modified to provide anchorage for the plant and take in water and nutrients into the plant body, which allows plants to grow taller and faster. They are most often below the surface of the soil, but roots can also be aerial or aerating, that is, growing up above the ground or especially above water.

Function
The major functions of roots are absorption of water, plant nutrition and anchoring of the plant body to the ground.

Anatomy
Root morphology is divided into four zones: the root cap, the apical meristem, the elongation zone, and the hair. The root cap of new roots helps the root penetrate the soil. These root caps are sloughed off as the root goes deeper creating a slimy surface that provides lubrication. The apical meristem behind the root cap produces new root cells that elongate. Then, root hairs form that absorb water and mineral nutrients from the soil. The first root in seed producing plants is the radicle, which expands from the plant embryo after seed germination.

When dissected, the arrangement of the cells in a root is root hair, epidermis, epiblem, cortex, endodermis, pericycle and, lastly, the vascular tissue in the centre of a root to transport the water absorbed by the root to other places of the plant.

Perhaps the most striking characteristic of roots that distinguishes them from other plant organs such as stem-branches and leaves is that roots have an endogenous origin, i.e., they originate and develop from an inner layer of the mother axis, such as pericycle. In contrast, stem-branches and leaves are exogenous, i.e., they start to develop from the cortex, an outer layer.

In response to the concentration of nutrients, roots also synthesise cytokinin, which acts as a signal as to how fast the shoots can grow. Roots often function in storage of food and nutrients. The roots of most vascular plant species enter into symbiosis with certain fungi to form mycorrhizae, and a large range of other organisms including bacteria also closely associate with roots.

Definition
In its simplest form, the term root system architecture (RSA) refers to the spatial configuration of a plant's root system. This system can be extremely complex and is dependent upon multiple factors such as the species of the plant itself, the composition of the soil and the availability of nutrients. Root architecture plays the important role of providing a secure supply of nutrients and water as well as anchorage and support.

The configuration of root systems serves to structurally support the plant, compete with other plants and for uptake of nutrients from the soil. Roots grow to specific conditions, which, if changed, can impede a plant's growth. For example, a root system that has developed in dry soil may not be as efficient in flooded soil, yet plants are able to adapt to other changes in the environment, such as seasonal changes.

Terms and components
The main terms used to classify the architecture of a root system are:

All components of the root architecture are regulated through a complex interaction between genetic responses and responses due to environmental stimuli. These developmental stimuli are categorised as intrinsic, the genetic and nutritional influences, or extrinsic, the environmental influences and are interpreted by signal transduction pathways.

Extrinsic factors affecting root architecture include gravity, light exposure, water and oxygen, as well as the availability or lack of nitrogen, phosphorus, sulphur, aluminium and sodium chloride. The main hormones (intrinsic stimuli) and respective pathways responsible for root architecture development include:

Growth
Early root growth is one of the functions of the apical meristem located near the tip of the root. The meristem cells more or less continuously divide, producing more meristem, root cap cells (these are sacrificed to protect the meristem), and undifferentiated root cells. The latter become the primary tissues of the root, first undergoing elongation, a process that pushes the root tip forward in the growing medium. Gradually these cells differentiate and mature into specialized cells of the root tissues.

Growth from apical meristems is known as primary growth, which encompasses all elongation. Secondary growth encompasses all growth in diameter, a major component of woody plant tissues and many nonwoody plants. For example, storage roots of sweet potato have secondary growth but are not woody. Secondary growth occurs at the lateral meristems, namely the vascular cambium and cork cambium. The former forms secondary xylem and secondary phloem, while the latter forms the periderm.

In plants with secondary growth, the vascular cambium, originating between the xylem and the phloem, forms a cylinder of tissue along the stem and root. The vascular cambium forms new cells on both the inside and outside of the cambium cylinder, with those on the inside forming secondary xylem cells, and those on the outside forming secondary phloem cells. As secondary xylem accumulates, the "girth" (lateral dimensions) of the stem and root increases. As a result, tissues beyond the secondary phloem including the epidermis and cortex, in many cases tend to be pushed outward and are eventually "sloughed off" (shed).

At this point, the cork cambium begins to form the periderm, consisting of protective cork cells. The walls of cork cells contains suberin thickenings, which is an extra cellular complex biopolymer. The suberin thickenings functions by providing a physical barrier, protection against pathogens and by preventing water loss from the surrounding tissues. In addition, it also aids the process of wound healing in plants. It is also postulated that suberin could be a component of the apoplastic barrier (present at the outer cell layers of roots) which prevents toxic compounds from entering the root and reduces radial oxygen loss (ROL) from the aerenchyma during waterlogging. In roots, the cork cambium originates in the pericycle, a component of the vascular cylinder.

The vascular cambium produces new layers of secondary xylem annually. The xylem vessels are dead at maturity (in some) but are responsible for most water transport through the vascular tissue in stems and roots. Tree roots usually grow to three times the diameter of the branch spread, only half of which lie underneath the trunk and canopy. The roots from one side of a tree usually supply nutrients to the foliage on the same side. Some families however, such as Sapindaceae (the maple family), show no correlation between root location and where the root supplies nutrients on the plant.

Regulation
There is a correlation of roots using the process of plant perception to sense their physical environment to grow, including the sensing of light, and physical barriers. Plants also sense gravity and respond through auxin pathways, resulting in gravitropism. Over time, roots can crack foundations, snap water lines, and lift sidewalks. Research has shown that roots have ability to recognize 'self' and 'non-self' roots in same soil environment.

The correct environment of air, mineral nutrients and water directs plant roots to grow in any direction to meet the plant's needs. Roots will shy or shrink away from dry or other poor soil conditions.

Gravitropism directs roots to grow downward at germination, the growth mechanism of plants that also causes the shoot to grow upward. Different types of roots such as primary, seminal, lateral and crown are maintained at different gravitropic setpoint angles i.e. the direction in which they grow. Recent research show that root angle in cereal crops such as barley and wheat is regulated by a novel gene called Enhanced Gravitropism 1 (EGT1).

Research indicates that plant roots growing in search of productive nutrition can sense and avoid soil compaction through diffusion of the gas ethylene.

Shade avoidance response
In order to avoid shade, plants utilize a shade avoidance response. When a plant is under dense vegetation, the presence of other vegetation nearby will cause the plant to avoid lateral growth and experience an increase in upward shoot, as well as downward root growth. In order to escape shade, plants adjust their root architecture, most notably by decreasing the length and amount of lateral roots emerging from the primary root. Experimentation of mutant variants of Arabidopsis thaliana found that plants sense the Red to Far Red light ratio that enters the plant through photoreceptors known as phytochromes. Nearby plant leaves will absorb red light and reflect far-red light, which will cause the ratio red to far red light to lower. The phytochrome PhyA that senses this Red to Far Red light ratio is localized in both the root system as well as the shoot system of plants, but through knockout mutant experimentation, it was found that root localized PhyA does not sense the light ratio, whether directly or axially, that leads to changes in the lateral root architecture. Research instead found that shoot localized PhyA is the phytochrome responsible for causing these architectural changes of the lateral root. Research has also found that phytochrome completes these architectural changes through the manipulation of auxin distribution in the root of the plant. When a low enough Red to Far Red ratio is sensed by PhyA, the phyA in the shoot will be mostly in its active form. In this form, PhyA stabilize the transcription factor HY5 causing it to no longer be degraded as it is when phyA is in its inactive form. This stabilized transcription factor is then able to be transported to the roots of the plant through the phloem, where it proceeds to induce its own transcription as a way to amplify its signal. In the roots of the plant HY5 functions to inhibit an auxin response factor known as ARF19, a response factor responsible for the translation of PIN3 and LAX3, two well known auxin transporting proteins. Thus, through manipulation of ARF19, the level and activity of auxin transporters PIN3 and LAX3 is inhibited. Once inhibited, auxin levels will be low in areas where lateral root emergence normally occurs, resulting in a failure for the plant to have the emergence of the lateral root primordium through the root pericycle. With this complex manipulation of Auxin transport in the roots, lateral root emergence will be inhibited in the roots and the root will instead elongate downwards, promoting vertical plant growth in an attempt to avoid shade.

Research of Arabidopsis has led to the discovery of how this auxin mediated root response works. In an attempt to discover the role that phytochrome plays in lateral root development, Salisbury et al. (2007) worked with Arabidopsis thaliana grown on agar plates. Salisbury et al. used wild type plants along with varying protein knockout and gene knockout Arabidopsis mutants to observe the results these mutations had on the root architecture, protein presence, and gene expression. To do this, Salisbury et al. used GFP fluorescence along with other forms of both macro and microscopic imagery to observe any changes various mutations caused. From these research, Salisbury et al. were able to theorize that shoot located phytochromes alter auxin levels in roots, controlling lateral root development and overall root architecture. In the experiments of van Gelderen et al. (2018), they wanted to see if and how it is that the shoot of A. thaliana alters and affects root development and root architecture. To do this, they took Arabidopsis plants, grew them in agar gel, and exposed the roots and shoots to separate sources of light. From here, they altered the different wavelengths of light the shoot and root of the plants were receiving and recorded the lateral root density, amount of lateral roots, and the general architecture of the lateral roots. To identify the function of specific photoreceptors, proteins, genes, and hormones, they utilized various Arabidopsis knockout mutants and observed the resulting changes in lateral roots architecture. Through their observations and various experiments, van Gelderen et al. were able to develop a mechanism for how root detection of Red to Far-red light ratios alter lateral root development.

Types
A true root system consists of a primary root and secondary roots (or lateral roots).
 * the diffuse root system: the primary root is not dominant; the whole root system is fibrous and branches in all directions. Most common in monocots. The main function of the fibrous root is to anchor the plant.

Specialized

The roots, or parts of roots, of many plant species have become specialized to serve adaptive purposes besides the two primary functions, described in the introduction.
 * Adventitious roots arise out-of-sequence from the more usual root formation of branches of a primary root, and instead originate from the stem, branches, leaves, or old woody roots. They commonly occur in monocots and pteridophytes, but also in many dicots, such as clover (Trifolium), ivy (Hedera), strawberry (Fragaria) and willow (Salix). Most aerial roots and stilt roots are adventitious. In some conifers adventitious roots can form the largest part of the root system. Adventitious root formation is enhanced in many plant species during (partial) submergence, to increase gas exchange and storage of gases like oxygen. Distinct types of adventitious roots can be classified and are dependent on morphology, growth dynamics and function.
 * Aerating roots (or knee root or knee or pneumatophores): roots rising above the ground, especially above water such as in some mangrove genera (Avicennia, Sonneratia). In some plants like Avicennia the erect roots have a large number of breathing pores for exchange of gases.
 * Aerial roots: roots entirely above the ground, such as in ivy (Hedera) or in epiphytic orchids. Many aerial roots are used to receive water and nutrient intake directly from the air – from fogs, dew or humidity in the air. Some rely on leaf systems to gather rain or humidity and even store it in scales or pockets. Other aerial roots, such as mangrove aerial roots, are used for aeration and not for water absorption. Other aerial roots are used mainly for structure, functioning as prop roots, as in maize or anchor roots or as the trunk in strangler fig. In some Epiphytes – plants living above the surface on other plants, aerial roots serve for reaching to water sources or reaching the surface, and then functioning as regular surface roots.
 * Canopy roots/arboreal roots: roots that form when tree branches support mats of epiphytes and detritus, which hold water and nutrients in the canopy. They grow out into these mats, likely to utilize the available nutrients and moisture.
 * Contractile roots: roots that pull bulbs or corms of monocots, such as hyacinth and lily, and some taproots, such as dandelion, deeper in the soil through expanding radially and contracting longitudinally. They have a wrinkled surface.
 * Coarse roots: roots that have undergone secondary thickening and have a woody structure. These roots have some ability to absorb water and nutrients, but their main function is transport and to provide a structure to connect the smaller diameter, fine roots to the rest of the plant.
 * Dimorphic root systems: roots with two distinctive forms for two separate functions
 * Fine roots: typically primary roots <2 mm diameter that have the function of water and nutrient uptake. They are often heavily branched and support mycorrhizas. These roots may be short lived, but are replaced by the plant in an ongoing process of root 'turnover'.
 * Haustorial roots: roots of parasitic plants that can absorb water and nutrients from another plant, such as in mistletoe (Viscum album) and dodder.
 * Propagative roots: roots that form adventitious buds that develop into aboveground shoots, termed suckers, which form new plants, as in Canada thistle, cherry and many others.
 * Proteoid roots or cluster roots: dense clusters of rootlets of limited growth that develop under low phosphate or low iron conditions in Proteaceae and some plants from the following families Betulaceae, Casuarinaceae, Elaeagnaceae, Moraceae, Fabaceae and Myricaceae.
 * Stilt roots: adventitious support roots, common among mangroves. They grow down from lateral branches, branching in the soil.
 * Storage roots: roots modified for storage of food or water, such as carrots and beets. They include some taproots and tuberous roots.
 * Structural roots: large roots that have undergone considerable secondary thickening and provide mechanical support to woody plants and trees.
 * Surface roots: roots that proliferate close below the soil surface, exploiting water and easily available nutrients. Where conditions are close to optimum in the surface layers of soil, the growth of surface roots is encouraged and they commonly become the dominant roots.
 * Tuberous roots: fleshy and enlarged lateral roots for food or water storage, e.g. sweet potato. A type of storage root distinct from taproot.
 * Photosynthetic roots: roots that are green and photosynthesize, providing sugar to the plant. They are similar to phylloclades. Several orchids have these, such as Dendrophylax and Taeniophyllum.
 * Root nodules: roots that harbor nitrogen-fixing soil bacteria. These are often very short and rounded. Root nodules are found in virtually all legumes.
 * Coralloid roots: similar to root nodules, these provide nitrogen to the plant. They are often larger than nodules, branched, and located at or near the soil surface, and harbor nitrogen-fixing cyanobacteria. They are only found in cycads.

Depths
The distribution of vascular plant roots within soil depends on plant form, the spatial and temporal availability of water and nutrients, and the physical properties of the soil. The deepest roots are generally found in deserts and temperate coniferous forests; the shallowest in tundra, boreal forest and temperate grasslands. The deepest observed living root, at least 60 m below the ground surface, was observed during the excavation of an open-pit mine in Arizona, US. Some roots can grow as deep as the tree is high. The majority of roots on most plants are however found relatively close to the surface where nutrient availability and aeration are more favourable for growth. Rooting depth may be physically restricted by rock or compacted soil close below the surface, or by anaerobic soil conditions.

Evolutionary history
The fossil record of roots—or rather, infilled voids where roots rotted after death—spans back to the late Silurian, about 430 million years ago. Their identification is difficult, because casts and molds of roots are so similar in appearance to animal burrows. They can be discriminated using a range of features. The evolutionary development of roots likely happened from the modification of shallow rhizomes (modified horizontal stems) which anchored primitive vascular plants combined with the development of filamentous outgrowths (called rhizoids) which anchored the plants and conducted water to the plant from the soil.

Environmental interactions
Light has been shown to have some impact on roots, but its not been studied as much as the effect of light on other plant systems. Early research in the 1930s found that light decreased the effectiveness of Indole-3-acetic acid on adventitious root initiation. Studies of the pea in the 1950s shows that lateral root formation was inhibited by light, and in the early 1960s researchers found that light could induce positive gravitropic responses in some situations. The effects of light on root elongation has been studied for monocotyledonous and dicotyledonous plants, with the majority of studies finding that light inhibited root elongation, whether pulsed or continuous. Studies of Arabidopsis in the 1990s showed negative phototropism and inhibition of the elongation of root hairs in light sensed by phyB.

Certain plants, namely Fabaceae, form root nodules in order to associate and form a symbiotic relationship with nitrogen-fixing bacteria called rhizobia. Owing to the high energy required to fix nitrogen from the atmosphere, the bacteria take carbon compounds from the plant to fuel the process. In return, the plant takes nitrogen compounds produced from ammonia by the bacteria.

Soil temperature is a factor that effects root initiation and length. Root length is usually impacted more dramatically by temperature than overall mass, where cooler temperatures tend to cause more lateral growth because downward extension is limited by cooler temperatures at subsoil levels. Needs vary by plant species, but in temperate regions cool temperatures may limit root systems. Cool temperature species like oats, rapeseed, rye, wheat fare better in lower temperatures than summer annuals like maize and cotton. Researchers have found that plants like cotton develop wider and shorter taproots in cooler temperatures. The first root originating from the seed usually has a wider diameter than root branches, so smaller root diameters are expected if temperatures increase root initiation. Root diameter also decreases when the root elongates.

Plant interactions
Plants can interact with one another in their environment through their root systems. Studies have demonstrated that plant-plant interaction occurs among root systems via the soil as a medium. Researchers have tested whether plants growing in ambient conditions would change their behavior if a nearby plant was exposed to drought conditions. Since nearby plants showed no changes in stomatal aperture researchers believe the drought signal spread through the roots and soil, not through the air as a volatile chemical signal.

Soil interactions
Soil microbiota can suppress both disease and beneficial root symbionts (mycorrhizal fungi are easier to establish in sterile soil). Inoculation with soil bacteria can increase internode extension, yield and quicken flowering. The migration of bacteria along the root varies with natural soil conditions. For example, research has found that the root systems of wheat seeds inoculated with Azotobacter showed higher populations in soils favorable to Azotobacter growth. Some studies have been unsuccessful in increasing the levels of certain microbes (such as P. fluorescens) in natural soil without prior sterilization.

Grass root systems are beneficial at reducing soil erosion by holding the soil together. Perennial grasses that grow wild in rangelands contribute organic matter to the soil when their old roots decay after attacks by beneficial fungi, protozoa, bacteria, insects and worms release nutrients.

Scientists have observed significant diversity of the microbial cover of roots at around 10 percent of three week old root segments covered. On younger roots there was even low coverage, but even on 3-month-old roots the coverage was only around 37%. Before the 1970s, scientists believed that the majority of the root surface was covered by microorganisms.

Nutrient absorption
Researchers studying maize seedlings found that calcium absorption was greatest in the apical root segment, and potassium at the base of the root. Along other root segments absorption was similar. Absorbed potassium is transported to the root tip, and to a lesser extent other parts of the root, then also to the shoot and grain. Calcium transport from the apical segment is slower, mostly transported upward and accumulated in stem and shoot.

Researchers found that partial deficiencies of K or P did not change the fatty acid composition of phosphatidyl choline in Brassica napus L. plants. Calcium deficiency did, on the other hand, lead to a marked decline of polyunsaturated compounds that would be expected to have negative impacts for integrity of the plant membrane, that could effect some properties like its permeability, and is needed for the ion uptake activity of the root membranes.

Economic importance
The term root crops refers to any edible underground plant structure, but many root crops are actually stems, such as potato tubers. Edible roots include cassava, sweet potato, beet, carrot, rutabaga, turnip, parsnip, radish, yam and horseradish. Spices obtained from roots include sassafras, angelica, sarsaparilla and licorice.

Sugar beet is an important source of sugar. Yam roots are a source of estrogen compounds used in birth control pills. The fish poison and insecticide rotenone is obtained from roots of Lonchocarpus spp. Important medicines from roots are ginseng, aconite, ipecac, gentian and reserpine. Several legumes that have nitrogen-fixing root nodules are used as green manure crops, which provide nitrogen fertilizer for other crops when plowed under. Specialized bald cypress roots, termed knees, are sold as souvenirs, lamp bases and carved into folk art. Native Americans used the flexible roots of white spruce for basketry.

Tree roots can heave and destroy concrete sidewalks and crush or clog buried pipes. The aerial roots of strangler fig have damaged ancient Mayan temples in Central America and the temple of Angkor Wat in Cambodia.

Trees stabilize soil on a slope prone to landslides. The root hairs work as an anchor on the soil.

Vegetative propagation of plants via cuttings depends on adventitious root formation. Hundreds of millions of plants are propagated via cuttings annually including chrysanthemum, poinsettia, carnation, ornamental shrubs and many houseplants.

Roots can also protect the environment by holding the soil to reduce soil erosion. This is especially important in areas such as sand dunes.

title: Root


text:
List of neurological conditions and disorders

This is a list of major and frequently observed neurological disorders (e.g., Alzheimer's disease), symptoms (e.g., back pain), signs (e.g., aphasia) and syndromes (e.g., Aicardi syndrome). There is disagreement over the definitions and criteria used to delineate various disorders and whether some of these conditions should be classified as mental disorders or in other ways.

#

 * 22q13 deletion syndrome

A

 * Abulia
 * Achromatopsia

 * Acquired brain injury
 * Agraphia
 * Agnosia
 * Aicardi syndrome
 * AIDS – neurological manifestations
 * Akinetopsia
 * Alexander Disease
 * Alien hand syndrome
 * Allan–Herndon–Dudley syndrome
 * Alternating hemiplegia of childhood
 * Alzheimer's disease
 * Amaurosis fugax
 * Amnesia
 * Amyotrophic lateral sclerosis
 * Anencephaly
 * Aneurysm
 * Angelman syndrome
 * Anosognosia
 * Aphasia
 * Aphantasia
 * Apraxia
 * Arachnoiditis
 * Arnold–Chiari malformation
 * Asomatognosia
 * Asperger syndrome
 * Ataxia
 * ATR-16 syndrome
 * Attention deficit hyperactivity disorder
 * Attention deficit hyperactivity disorder predominately inattentive
 * Auditory processing disorder
 * Autism spectrum disorder

B

 * Back pain
 * Behçet's disease
 * Bell's palsy
 * Bipolar disorder
 * Blindsight
 * Blindness
 * Blurred vision
 * Brain damage
 * Brachial plexus injury
 * Brain death
 * Brain injury
 * Brain infarction
 * Brain tumor
 * Brody myopathy

C

 * Canavan disease
 * Capgras delusion
 * Carpal tunnel syndrome
 * Causalgia
 * Central pain syndrome
 * Central pontine myelinolysis
 * Centronuclear myopathy
 * Cephalic disorder
 * Cerebral aneurysm
 * Cerebral arteriosclerosis
 * Cerebral atrophy
 * Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy
 * Cerebral dysgenesis–neuropathy–ichthyosis–keratoderma syndrome
 * Cerebral gigantism
 * Cerebral palsy
 * Cerebral vasculitis
 * Cerebrospinal fluid leak
 * Cervical spinal stenosis
 * Charcot–Marie–Tooth disease
 * Chiari malformation
 * Chorea
 * Chronic fatigue syndrome
 * Chronic inflammatory demyelinating polyneuropathy
 * Charles bonnet syndrome
 * Chronic pain
 * Cluster headache
 * Cockayne syndrome
 * Coffin–Lowry syndrome
 * Coma
 * Complex post-traumatic stress disorder
 * Complex regional pain syndrome
 * Compression neuropathy
 * Congenital distal spinal muscular atrophy
 * Congenital facial diplegia
 * Color blindness
 * Cornelia de Lange syndrome
 * Corticobasal degeneration
 * Cotard delusion
 * Cranial arteritis
 * Craniosynostosis
 * Creutzfeldt–Jakob disease
 * Cumulative trauma disorders
 * Cushing's syndrome
 * Cyclic vomiting syndrome
 * Cyclothymic disorder
 * Cytomegalic inclusion body disease
 * Cytomegalovirus Infection

D

 * Dandy–Walker syndrome
 * Dawson disease
 * De Morsier's syndrome
 * Dejerine–Klumpke palsy
 * Dejerine–Sottas disease
 * Delayed sleep phase disorder or syndrome
 * Dementia
 * Dermatillomania
 * Dermatomyositis
 * Developmental coordination disorder
 * Diabetic neuropathy
 * Disc herniation
 * Diffuse sclerosis
 * Diplopia
 * Disorders of consciousness
 * Distal hereditary motor neuropathy type V
 * Distal spinal muscular atrophy type 1
 * Distal spinal muscular atrophy type 2
 * Dizziness
 * Down syndrome
 * Dravet syndrome
 * Duchenne muscular dystrophy
 * Dysarthria
 * Dysautonomia
 * Dyscalculia
 * Dysphagia
 * Dysgraphia
 * Dyskinesia
 * Dyslexia
 * Dystonia

E

 * Empty sella syndrome
 * Encephalitis
 * Encephalocele
 * Encephalopathy
 * Encephalotrigeminal angiomatosis
 * Encopresis
 * Enuresis
 * Epilepsy
 * Epilepsy-intellectual disability in females
 * Erb's palsy
 * Erythromelalgia
 * Essential tremor
 * Exploding head syndrome

F

 * Fabry's disease
 * Fahr's syndrome
 * Fainting
 * Familial spastic paralysis
 * Fetal alcohol syndrome
 * Febrile seizures
 * Fisher syndrome
 * Fibromyalgia
 * Foville's syndrome
 * Fragile X syndrome
 * Fragile X-associated tremor/ataxia syndrome
 * Friedreich's ataxia
 * Frontotemporal dementia
 * Functional neurological symptom disorder

G

 * Gaucher's disease
 * Generalized anxiety disorder
 * Generalized epilepsy with febrile seizures plus
 * Gerstmann's syndrome
 * Giant cell arteritis
 * Giant cell inclusion disease
 * Globoid cell leukodystrophy
 * Gray matter heterotopia
 * Guillain–Barré syndrome

H

 * Head injury
 * Headache
 * Hemicrania Continua
 * Hemifacial spasm
 * Hemispatial neglect
 * Hereditary motor neuropathies
 * Hereditary spastic paraplegia
 * Heredopathia atactica polyneuritiformis
 * Herpes zoster
 * Herpes zoster oticus
 * Hirayama syndrome
 * Hirschsprung's disease
 * Holmes–Adie syndrome
 * Holoprosencephaly
 * HTLV-1 associated myelopathy
 * Huntington's disease
 * Hydrocephalia
 * Hydranencephaly
 * Hydrocephalus
 * Hypercortisolism
 * Hypoalgesia
 * Hypoesthesia
 * Hypoxia

I

 * Immune-mediated encephalomyelitis
 * Inclusion body myositis
 * Incontinentia pigmenti
 * Infantile spasms
 * Inflammatory myopathy
 * Intellectual disability
 * Intracranial cyst
 * Intracranial hypertension
 * Isodicentric 15

J

 * Joubert syndrome

K

 * Karak syndrome
 * Kearns–Sayre syndrome
 * Kinsbourne syndrome
 * Kleine–Levin syndrome
 * Klippel Feil syndrome
 * Krabbe disease
 * Korsakoff Syndrome
 * Kufor–Rakeb syndrome
 * Kugelberg–Welander disease – see Spinal muscular atrophy

L

 * Lafora disease
 * Lambert–Eaton myasthenic syndrome
 * Landau–Kleffner syndrome
 * Lateral medullary (Wallenberg) syndrome
 * Learning disabilities
 * Leigh's disease
 * Lennox–Gastaut syndrome
 * Lesch–Nyhan syndrome
 * Leukodystrophy
 * Leukoencephalopathy with vanishing white matter
 * Lewy body dementia
 * Lissencephaly
 * Locked-in syndrome
 * Lou Gehrig's disease – see Amyotrophic lateral sclerosis
 * Lumbar disc disease
 * Lumbar hernia
 * Lumbar spinal stenosis
 * Lupus erythematosus – neurological sequelae
 * Lyme disease

M

 * Machado–Joseph disease
 * Macrencephaly
 * Macrocephalia
 * Macropsia
 * Mal de debarquement
 * Megalencephalic leukoencephalopathy with subcortical cysts
 * Megalencephaly
 * Melkersson–Rosenthal syndrome
 * Menieres disease
 * Meningitis
 * Menkes disease
 * Metachromatic leukodystrophy
 * Microcephaly
 * Micropsia
 * Migraine
 * Mild brain injury
 * Miller Fisher syndrome
 * Mini-stroke (transient ischemic attack)
 * Misophonia
 * Mitochondrial myopathy
 * Mobius syndrome
 * Monomelic amyotrophy
 * Morvan syndrome
 * Motor neurone disease – see Amyotrophic lateral sclerosis
 * Motor skills disorder
 * Moyamoya disease
 * Mucopolysaccharidoses
 * Multifocal motor neuropathy
 * Multi-infarct dementia
 * Multiple sclerosis
 * Multiple system atrophy
 * Muscular dystrophy
 * Myalgic encephalomyelitis
 * Myasthenia gravis
 * Myelinoclastic diffuse sclerosis
 * Myoclonic Encephalopathy of infants
 * Myoclonus
 * Myopathy
 * Myotonia congenita
 * Myotubular myopathy

N

 * Narcolepsy
 * Neuralgia
 * Neuro-Behçet's disease
 * Neurofibromatosis
 * Neuroleptic malignant syndrome
 * Neuromyotonia
 * Neuronal ceroid lipofuscinosis
 * Neuronal migration disorders
 * Neuropathy
 * Neurosis
 * Niemann–Pick disease
 * Non-24-hour sleep–wake disorder
 * Nonverbal learning disorder

O

 * Occipital Neuralgia
 * Occult spinal dysraphism sequence
 * Ohtahara syndrome
 * Olivopontocerebellar atrophy
 * Opsoclonus myoclonus syndrome
 * Optic neuritis
 * Orthostatic hypotension
 * O'Sullivan–McLeod syndrome
 * Otosclerosis
 * Overuse syndrome

P

 * Palinopsia
 * PANDAS
 * Pantothenate kinase-associated neurodegeneration
 * Paraplegia
 * Paralysis
 * Paramyotonia congenita
 * Paresthesia
 * Paresis
 * Parkinson('s) disease
 * Paraneoplastic diseases
 * Paroxysmal attacks
 * Parry–Romberg syndrome
 * Pelizaeus–Merzbacher disease
 * Periodic paralyses
 * Peripheral neuropathy
 * Pervasive developmental disorders
 * Phantom limb / Phantom pain
 * Photic sneeze reflex
 * Phytanic acid storage disease
 * Pick's disease
 * Pinched nerve
 * Pituitary tumors
 * Polyneuropathy
 * PMG
 * Polio
 * Polymicrogyria
 * Polymyositis
 * Porencephaly
 * Post-polio syndrome
 * Postherpetic neuralgia
 * Posttraumatic stress disorder
 * Postural hypotension
 * Postural orthostatic tachycardia syndrome
 * Prader–Willi syndrome
 * Primary lateral sclerosis
 * Prion diseases
 * Progressive hemifacial atrophy
 * Progressive multifocal leukoencephalopathy
 * Progressive supranuclear palsy
 * Prosopagnosia
 * Pseudotumor cerebri

Q

 * Quadrantanopia
 * Quadriplegia

R

 * Rabies
 * Radiculopathy
 * Ramsay Hunt syndrome type I
 * Ramsay Hunt syndrome type II
 * Ramsay Hunt syndrome type III – see Ramsay–Hunt syndrome
 * Rasmussen encephalitis
 * Reflex neurovascular dystrophy
 * Refsum disease
 * REM sleep behavior disorder
 * Repetitive stress injury
 * Restless legs syndrome
 * Retrovirus-associated myelopathy
 * Rett syndrome
 * Reye's syndrome
 * Rhythmic movement disorder
 * Romberg syndrome

S

 * Savant syndrome
 * Saint Vitus dance
 * Sandhoff disease
 * Sanfilippo syndrome
 * Schilder's disease (two distinct conditions)
 * Schizencephaly
 * Sclerosis
 * Seizures
 * Sensory processing disorder
 * Septo-optic dysplasia
 * Shaken baby syndrome
 * Shingles
 * Shy–Drager syndrome
 * Sjögren's syndrome
 * Sleep apnea
 * Sleeping sickness
 * Slurred speech
 * Snatiation
 * Sotos syndrome
 * Spasticity
 * Spina bifida
 * Spinal and bulbar muscular atrophy
 * Spinal cord injury
 * Spinal cord tumors
 * Spinal muscular atrophy
 * Spinal muscular atrophy with respiratory distress type 1 – see Distal spinal muscular atrophy type 1
 * Spinocerebellar ataxia
 * Split-brain
 * Steele–Richardson–Olszewski syndrome – see Progressive supranuclear palsy
 * Stiff-person syndrome
 * Stroke
 * Sturge–Weber syndrome
 * Stuttering
 * Subacute sclerosing panencephalitis
 * Subcortical arteriosclerotic encephalopathy
 * Superficial siderosis
 * Sydenham's chorea
 * Syncope
 * Synesthesia
 * Syringomyelia
 * Substance use disorder

T

 * Traumatic encephalopathy
 * Tardive dyskinesia
 * Tarlov cyst
 * Tarsal tunnel syndrome
 * Tay–Sachs disease
 * Temporal arteritis
 * Temporal lobe epilepsy
 * Tetanus
 * Tethered spinal cord syndrome
 * Thalamocortical dysrhythmia
 * Thomsen disease
 * Thoracic outlet syndrome
 * Tic Douloureux
 * Tinnitus
 * Todd's paralysis
 * Tourette syndrome
 * Toxic encephalopathy
 * Transient ischemic attack
 * Transmissible spongiform encephalopathies
 * Transverse myelitis
 * Traumatic brain injury
 * Tremor
 * Trichotillomania
 * Trigeminal neuralgia
 * Tropical spastic paraparesis
 * Trypanosomiasis
 * Tuberous sclerosis

U

 * Unconsciousness
 * Unverricht–Lundborg disease

V

 * Vestibular schwannoma
 * Vertigo
 * Viliuisk encephalomyelitis
 * Visual Snow
 * Von Hippel–Lindau disease
 * Vulpian-Bernhardt Syndrome

W

 * Wallenberg's syndrome
 * Werdnig–Hoffmann disease – see Spinal muscular atrophy
 * Wernicke's encephalopathy
 * Wernicke Korsakoff syndrome
 * West syndrome
 * Whiplash
 * Williams syndrome
 * Wilson's disease

Y

 * Y-Linked hearing impairment

Z

 * Zellweger syndrome


text:
Talk:Apneist

This is certainly a valid first attempt at a definition, but it seems paradoxical that you would even want to define a word that you never heard of. By doing so, you are the one who "invents" the word. --Eclecticology, Wednesday, June 12, 2002

-

Well, it does seem to be used in at least one place in that sense: http://www.jp-petit.com/dangers/danger_eng/apnea_eng/apnea.htm

It also appears to be the name of a make of dive computer.

Oh, and Elba links to Apneist. -- Anon

Which is where I found it. I made the link to Apneist from Elba, looked up the guy's name, and guessed what the word means. -phma

http://www.iafdusa.com/ofrec.htm list apnea diving as one form of free diving but I couldn't find an explanation for what it meant. --rmhermen

I was more humored by the entry than anything; notwithstanding the "Wikipedia is not a dictionary rule. I was also piqued by the paradox.  I'm sure somebody will be interested enough to make the article into something more than a mere dictionary  type definition.  The magazine site at apnea.fr looks interesting.  I'd always considered apnea to be a medical condition, but as they say, "Different strokes for different folks."  --Éclecticologie.

Today I came across the term Apnoeist on the website http://www.ioua.de/iuoa.htm (which seems to be some kind of maybe sexistic insider joke) and due to I never heard about that word before (I was looking for pictograms at Google), I looked first for a Wikipedia entry and with Googles  feature, but without success. It then took me a while to find the appropriate Wikipedia entry (Apnea) with help of Googles "do you mean" feature, so I also added Apnoeist as an redirect to Apnea as well as two other redirects for the american and british spelling of some of the related term apneic (resp. apnoeic) used in the article itself. --XTaran | Talk 17:58, 24 Mar 2004 (UTC)

title: Talk:Apneist


text:
Talk:Lares (Roman deities)

Wrong link target
The link to Mani appears to have nothing to do with Romans. --rmhermen

title: Talk:Lares (Roman deities)