All articles starting with N
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Nicotinamide riboside
Nicotinamide riboside (NR), a vitamin B3 form and NAD+ precursor discovered by Charles Brenner in 2004, raises blood NAD+ when taken orally but showed no clinical benefit in the 2026 NOPARK Parkinson trial.
Nicotinate
Nicotinate is the anion formed when nicotinic acid, best known as niacin or vitamin B3, loses its carboxyl proton, and is the compound's major form at physiological pH.
Nicotine
Nicotine (C10H14N2) is the addictive alkaloid of tobacco acting on nicotinic acetylcholine receptors; found in cigarettes, vapes, and pouches, harmful to adolescent brain development, and used medicinally as replacement therapy.
Nicotine Chewing Gum
Nicotine chewing gum (nicotine polacrilex, brand Nicorette) is the first nicotine replacement therapy, developed in Sweden by Ove Fernö, FDA-approved 1984, OTC 1996; 2 mg and 4 mg doses roughly double quit odds versus control.
Nicotine dependence
Nicotine dependence, also called tobacco use disorder, is a chronic relapsing disorder of nicotine regulation involving craving, tolerance, and withdrawal, driven by nicotinic acetylcholine receptor effects on dopamine circuits, and treated with NRT, varenicline, bupropion, or cytisine.
Nicotine intoxication
Nicotine intoxication (ICD-11 6C4A.3), also called tobacco intoxication, is a transient toxic condition from nicotine exposure, with early stimulation then depression, vomiting, seizures, and possible cardiovascular collapse; no specific antidote exists.
Nicotine poisoning
Nicotine poisoning: toxic effects of nicotine swallowed, inhaled, or absorbed through skin or eyes, mainly from e-liquids; two-phase vomiting-to-paralysis syndrome, no antidote, children under 6 most affected.
Nicotine pouch
Nicotine pouch (oral nicotine pouch): tobacco-free fiber pouch of nicotine powder or salts, flavorings, and cellulose, placed between gum and lip. Entered US market 2016; first FDA authorization (ZYN) January 2025; not FDA-approved for cessation.
Nicotine replacement therapy
Nicotine replacement therapy (NRT) is a smoking cessation treatment supplying nicotine through gum, patches, lozenges, inhalers, or sprays; trials show it raises quitting rates by 50% to 60%.
Nicotine withdrawal
Nicotine withdrawal: physical and psychological symptoms (cravings, irritability, insomnia, poor concentration) after stopping nicotine; begins 4-24 hours after last dose, peaks days 2-3, fades within 3-4 weeks; treated with NRT, varenicline, cytisine, bupropion, e-cigarettes, and counseling.
Nicotinic acetylcholine receptor
Nicotinic acetylcholine receptor (nAChR): pentameric Cys-loop ligand-gated cation channel activated by acetylcholine and nicotine; 16 human subunit genes; α4β2 most abundant CNS subtype; identified biochemically in 1970 via α-bungarotoxin.
Nicotinic acid
Nicotinic acid (niacin, vitamin B3, pyridine-3-carboxylic acid) is a vitamin whose deficiency causes pellagra and a lipid-lowering drug that raises HDL and lowers triglycerides, LDL, and lipoprotein(a), but adds no cardiovascular benefit to statins.
Nicoya
Nicoya is a town and canton in Guanacaste province, Costa Rica, named for a Chorotega chief and the region's largest indigenous chiefdom at Spanish contact in 1519.
Nicoya Peninsula
Nicoya Peninsula (Península de Nicoya), Costa Rica's largest peninsula on the Pacific coast across the Gulf of Nicoya; built of the Jurassic-Cretaceous Nicoya Complex ophiolite, sits above the Middle America Trench subduction zone, and is a validated blue zone of exceptional longevity.
Nicoya Sinus
Nicoya Sinus: bay-shaped dark feature (sinus) on Titan, 130 km wide at 74.8N, 251.2W, IAU-approved January 19, 2015, named after the Gulf of Nicoya, Costa Rica.
Nictitating membrane
Nictitating membrane, or third eyelid (plica semilunaris in humans), a conjunctival fold hidden in the medial canthus that sweeps over the cornea of birds, reptiles, sharks, and many mammals to protect the eye, spread tears, and secrete IgA.
Nicu Ceaușescu
Nicu Ceaușescu (Nicolae Ceaușescu, 1951–1996), youngest son of Romania's dictator, held youth-league, ministerial, and Sibiu county party posts; tried after 1989, died in Vienna of cirrhosis.
Nicu Sebe
Nicu Sebe (Niculae Sebe) is a computer scientist in computer vision and machine learning, a full professor at the University of Trento and head of AI at Humans.ai.
Nicu Vlad
Nicu Vlad (Nicolae Vlad), Romanian weightlifter born 1963: 1984 Olympic gold, 1988 silver, 1996 bronze, three world titles, and the lifter behind the Romanian deadlift exercise.
Nicușor Dan
Nicușor Dan (Nicușor-Daniel Dan), Romanian mathematician and politician, president of Romania since 26 May 2025; former Bucharest mayor, USR founder, two-time IMO gold medalist, won the 2025 rerun runoff with 53.6% against George Simion.
Nida Fazli
Nida Fazli (Urdu: ندا فاضلی), born Muqtada Hasan Fazli, was an Indian poet and songwriter who wrote in Urdu and Hindi and gave Urdu poetry a colloquial tone.
Nida Senff
Nida Senff (Dina Willemina Jacoba Senff, 1920-1995), Dutch backstroke swimmer; won 1936 Berlin Olympic 100 m backstroke gold in 1:18.9 after missing the turn, and set five backstroke world records; ISHOF inductee 1983.
Nidaba (crater on Ganymede)
Nidaba is a 199-km-diameter impact crater and palimpsest on Jupiter's moon Ganymede at 17.75N, 123.43W, IAU-named in 1985 for a Sumerian grain goddess, dominated by undulating plains.
Nidal Čelik
Nidal Čelik (born 2006, Sarajevo) is a Bosnian center-back, 192 cm, at RC Lens since a February 2025 transfer from FK Sarajevo; Bosnia senior debut May 2026, 2 caps, 2026 World Cup squad member.
Nidal Hasan
Nidal Malik Hasan, born 1970, former U.S. Army major and psychiatrist who killed 13 people in the November 5, 2009 Fort Hood shooting; sentenced to death in 2013, scheduled for firing-squad execution December 3, 2026, the first U.S. military execution since 1961.
Nidaros Cathedral
Nidaros Cathedral (Nidarosdomen), also known as Trondheim Cathedral, is a medieval Gothic cathedral in Trondheim, Norway, built over the tomb of St. Olav, where Norwegian monarchs are consecrated.
Nidderau
Nidderau, a town in Hesse's Main-Kinzig-Kreis with five districts (Ostheim, Eichen, Erbstadt, Heldenbergen, Windecken), known for Neolithic Linear Pottery settlements, Roman earth camps and Limes evidence, and Celtic graves.
Nidec Corporation
Nidec Corporation (ニデック株式会社) is a Japanese motor manufacturer headquartered in Kyoto, founded in 1973 by Shigenobu Nagamori, supplying precision motors for hard disk drives, cars, and appliances.
Nidhal Guessoum
Nidhal Guessoum is an Algerian astrophysicist and professor at the American University of Sharjah, known for gamma-ray astrophysics research and his 2010 book Islam's Quantum Question.
Nidhanpur copperplates of Bhaskaravarman
The Nidhanpur copperplates (निधानपुर ताम्रपत्र) are a 7th-century Sanskrit charter issued by Bhaskaravarman, king of Kamarupa in Assam, regranting the Mayurasalmal estate to Brahmanas; the plates were found at Nidhanpur in Sylhet, Bangladesh.