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Chemistry

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Valery Legasov

Valery Alekseyevich Legasov was a Soviet inorganic chemist and a member of the Academy of Sciences of the USSR. He is now mainly remembered for his work as the chief of the commission investigating the Chernobyl disaster.

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Cannabidiol

Cannabidiol (CBD) is a naturally occurring cannabinoid constituent of cannabis. It was discovered in 1940 and initially thought not to be pharmaceutically active. It is one of at least 113 cannabinoids identified in hemp plants, accounting for up to 40% of the plant's extract. As of 2018 in the United States, Food and Drug Administration approval of cannabidiol as a prescription drug for medical uses has been limited to two rare forms of childhood epilepsy.

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Helium

Helium is a chemical element with symbol He and atomic number 2. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas, the first in the noble gas group in the periodic table. Its boiling point is the lowest among all the elements. After hydrogen, helium is the second lightest and second most abundant element in the observable universe, being present at about 24% of the total elemental mass, which is more than 12 times the mass of all the heavier elements combined. Its abundance is similar to this figure in the Sun and in Jupiter. This is due to the very high nuclear binding energy of helium-4 with respect to the next three elements after helium. This helium-4 binding energy also accounts for why it is a product of both nuclear fusion and radioactive decay. Most helium in the universe is helium-4, the vast majority of which was formed during the Big Bang. Large amounts of new helium are being created by nuclear fusion of hydrogen in stars.

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MDMA

3,4-Methyl​enedioxy​methamphetamine (MDMA), commonly known as ecstasy (E), is a psychoactive drug primarily used as a recreational drug. The desired effects include altered sensations and increased energy, empathy, and pleasure. When taken by mouth, effects begin after 30–45 minutes and last 3–6 hours. As of 2018, MDMA has no approved medical uses.

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Cocaine

Cocaine, also known as coke, is a strong stimulant mostly used as a recreational drug. It is commonly snorted, inhaled as smoke, or dissolved and injected into a vein. Mental effects may include loss of contact with reality, an intense feeling of happiness, or agitation. Physical symptoms may include a fast heart rate, sweating, and large pupils. High doses can result in very high blood pressure or body temperature. Effects begin within seconds to minutes of use and last between five and ninety minutes. Cocaine has a small number of accepted medical uses such as numbing and decreasing bleeding during nasal surgery.

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Fentanyl

Fentanyl is an opioid used as a pain medication and together with other medications for anesthesia. Fentanyl is also made illegally and used as a recreational drug, often mixed with heroin or cocaine. It has a rapid onset and effects generally last less than an hour or two. Medically, fentanyl is used by injection, as a patch on the skin, as a nasal spray, or in the mouth.

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Gabapentin

Gabapentin is a medication which is used to treat partial seizures, neuropathic pain, hot flashes, and restless legs syndrome. It is recommended as one of a number of first-line medications for the treatment of neuropathic pain caused by diabetic neuropathy, postherpetic neuralgia, and central neuropathic pain. About 15% of those given gabapentin for diabetic neuropathy or postherpetic neuralgia have a measurable benefit. Gabapentin is taken by mouth.

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Cannabis (drug)

Cannabis, also known as marijuana among other names, is a psychoactive drug from the Cannabis plant used for medical or recreational purposes. The main psychoactive part of cannabis is tetrahydrocannabinol (THC), one of 483 known compounds in the plant, including at least 65 other cannabinoids. Cannabis can be used by smoking, vaporizing, within food, or as an extract.

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Lysergic acid diethylamide

Lysergic acid diethylamide (LSD), also known as acid, is a hallucinogenic drug. Effects typically include altered thoughts, feelings, and awareness of one's surroundings. Many users see or hear things that do not exist. Dilated pupils, increased blood pressure, and increased body temperature are typical. Effects typically begin within half an hour and can last for up to 12 hours. It is used mainly as a recreational drug and for spiritual reasons.

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Tramadol

Tramadol, sold under the brand name Ultram among others, is an opioid pain medication used to treat moderate to moderately severe pain. When taken by mouth in an immediate-release formulation, the onset of pain relief usually occurs within an hour. It is often combined with paracetamol (acetaminophen) as this is known to improve the efficacy of tramadol in relieving pain.

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Adderall

Adderall, Adderall XR, and Mydayis are combination drugs containing four salts of the two enantiomers of amphetamine, a central nervous system (CNS) stimulant of the phenethylamine class. Adderall is used in the treatment of attention deficit hyperactivity disorder (ADHD) and narcolepsy. It is also used as an athletic performance enhancer and cognitive enhancer, and recreationally as an aphrodisiac and euphoriant. By salt content, the active ingredients of Adderall, Adderall XR, and Mydayis are 25% levoamphetamine salts and 75% dextroamphetamine salts.

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Paracetamol

Paracetamol, also known as acetaminophen or APAP, is a medicine used to treat pain and fever. It is typically used for mild to moderate pain relief. Evidence for its use to relieve fever in children is mixed. It is often sold in combination with other medications, such as in many cold medications. In combination with opioid pain medication, paracetamol is also used for severe pain such as cancer pain and pain after surgery. It is typically used either by mouth or rectally but is also available intravenously. Effects last between two and four hours.

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Methamphetamine

Methamphetamine is a potent central nervous system (CNS) stimulant that is mainly used as a recreational drug and less commonly as a second-line treatment for attention deficit hyperactivity disorder and obesity. Methamphetamine was discovered in 1893 and exists as two enantiomers: levo-methamphetamine and dextro-methamphetamine. Methamphetamine properly refers to a specific chemical, the racemic free base, which is an equal mixture of levomethamphetamine and dextromethamphetamine in their pure amine forms. It is rarely prescribed over concerns involving human neurotoxicity and potential for recreational use as an aphrodisiac and euphoriant, among other concerns, as well as the availability of safer substitute drugs with comparable treatment efficacy. Dextromethamphetamine is a much stronger CNS stimulant than levomethamphetamine.

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Diazepam

Diazepam, first marketed as Valium, is a medicine of the benzodiazepine family that typically produces a calming effect. It is commonly used to treat a range of conditions including anxiety, alcohol withdrawal syndrome, benzodiazepine withdrawal syndrome, muscle spasms, seizures, trouble sleeping, and restless legs syndrome. It may also be used to cause memory loss during certain medical procedures. It can be taken by mouth, inserted into the rectum, injected into muscle, or injected into a vein. When given into a vein, effects begin in one to five minutes and last up to an hour. By mouth, effects may take 40 minutes to begin.

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Dopamine

Dopamine is an organic chemical of the catecholamine and phenethylamine families that plays several important roles in the brain and body. It is an amine synthesized by removing a carboxyl group from a molecule of its precursor chemical L-DOPA, which is synthesized in the brain and kidneys. Dopamine is also synthesized in plants and most animals. In the brain, dopamine functions as a neurotransmitter—a chemical released by neurons to send signals to other nerve cells. The brain includes several distinct dopamine pathways, one of which plays a major role in the motivational component of reward-motivated behavior. The anticipation of most types of rewards increases the level of dopamine in the brain, and many addictive drugs increase dopamine release or block its reuptake into neurons following release. Other brain dopamine pathways are involved in motor control and in controlling the release of various hormones. These pathways and cell groups form a dopamine system which is neuromodulatory.