All articles starting with U

Urdu Ki Aakhri Kitab

Urdu Ki Aakhri Kitab (اردو کی آخری کتاب, "The Last Book of Urdu") is a 1971 work of Urdu satire by Ibn-e-Insha, written as a parody school textbook.

Urdu literary criticism

Urdu literary criticism (اردو تنقید, Urdu tanqeed) evaluates and theorizes Urdu poetry and prose; it took modern organized form with Altaf Hussain Hali's Muqaddama of 1893.

Urdu poetry (اردو شاعری) is South Asian verse in Urdu, born in the Deccan and Delhi from the 13th century. Key forms are the ghazal, nazm, masnavi, qasida, and marsiya; masters include Khusrau, Mir, Ghalib, Iqbal, and Faiz.

Urdu prose

Urdu prose (اردو نثر) is the body of non-verse literature in the Urdu language, spanning novels, tales, essays, and journalism; it matured after Fort William College was founded in Calcutta in 1800.

Urdu script reform

Urdu script reform covers recurring attempts, from the late nineteenth century to today, to change how Urdu is written, including Romanization and orthographic standardization efforts in India and Pakistan.

Urdu translations of the Quran

Urdu translations of the Quran are complete renderings of the Arabic Quran into Urdu, a tradition that began in Delhi in the late eighteenth century.

Sep 19, 2026

Urdukuga

Urdukuga of Isin was the thirteenth king of the First Dynasty of Isin in southern Mesopotamia, reigning four years around 1831–1828 BC between Iter-piša and Sîn-māgir.

Urea

Urea, also called carbamide, is an organic compound and the principal end product of protein catabolism in mammals, produced industrially from ammonia and carbon dioxide as a major nitrogen fertilizer.

Urea breath test

The urea breath test (UBT) is a noninvasive diagnostic test in which swallowed labeled urea reveals active Helicobacter pylori infection, and it confirms cure after eradication therapy.

Oct 20, 2026

Urea carboxylase

Urea carboxylase (UC), the biotin- and ATP-dependent enzyme carboxylating urea to allophanate in the two-step urea amidolyase pathway of bacteria, fungi, and green algae; distinct from urease, and functionally independent of allophanate hydrolase.

Urea cycle

Urea cycle (Krebs-Henseleit cycle, ornithine cycle): five-enzyme liver pathway converting ammonia and bicarbonate to urea using three ATP; defects cause urea cycle disorders such as OTC deficiency.

Urea electrolysis

Urea electrolysis is an electrochemical process in which urea is oxidized at the anode rather than water, lowering the voltage needed for hydrogen production from the 1.23 V of water electrolysis to 0.37 V.

Urea electrooxidation

Urea electrooxidation is the electrochemical oxidation of urea at an anode, a six-electron reaction used to produce hydrogen with about 30% less energy than water electrolysis.

Oct 15, 2026

Urea nitrate

Urea nitrate, also called uronium nitrate, is a white crystalline explosive salt made from urea and nitric acid, used as the main charge in the 1993 World Trade Center bombing.

Urea oxidation reaction

The urea oxidation reaction is the electrochemical oxidation of urea, usually on nickel catalysts in alkaline solution, studied for low-voltage hydrogen production and treating urine wastewater.

Urea transporter

Urea transporters (UT-A/SLC14A2, UT-B/SLC14A1) are facilitated urea channels concentrated in the kidney medulla, where they enable urine concentration; targets of experimental sodium-sparing diuretics called urearetics.

Urea-cycle intermediates in animals

Urea-cycle intermediates in animals are the soluble metabolites, chiefly ornithine, citrulline, argininosuccinate, and arginine, that carry nitrogen through the ornithine–urea cycle, which converts toxic ammonia into urea.

Urea-formaldehyde

Urea-formaldehyde, also called urea-methanal, is a thermosetting resin made by condensing urea with formaldehyde, used mainly as a low-cost adhesive for particleboard and other wood panels, though it can emit formaldehyde.

Oct 15, 2026

Urea-thickened grease

Urea-thickened grease, also called polyurea grease, is an ashless lubricating grease with high dropping points above 260 °C, first reported in 1954 and used in sealed electric-motor bearings and constant-velocity joints.

Oct 21, 2026

Ureaplasma

Ureaplasma: genus of cell-wall-less urease-producing bacteria (U. parvum, U. urealyticum) colonizing the human urogenital tract; common commensals, occasional urethritis and preterm-birth associations, rising macrolide resistance.

Ureaplasma parvum

Ureaplasma parvum, formerly U. urealyticum biovar 1, is a cell-wall-less human urogenital bacterium with serovars 1, 3, 6, 14, a 0.75–0.78 Mbp genome, and debated roles in preterm birth and neonatal lung disease.

Ureaplasma urealyticum

Ureaplasma urealyticum, a cell-wall-less urea-hydrolyzing bacterium of the human urogenital tract (split from U. parvum in 2002), common commensal in 40–80% of healthy women, studied as a possible cause of NGU, preterm birth, and neonatal bronchopulmonary dysplasia.

Urease

Urease (urea amidohydrolase) is a nickel-dependent enzyme hydrolyzing urea to ammonia and carbamate; first enzyme crystallized (Sumner, 1926, jack bean) and first nickel enzyme (1975), with a di-nickel active site.

Urease test

The urease test is a microbiological assay that detects urease activity by a pH color change when urea breaks down to ammonia, identifying urease-producing bacteria and yeasts.

Oct 21, 2026

URECA study

URECA (Urban Environment and Childhood Asthma) is an NIAID-sponsored US birth cohort of 560 high-risk inner-city children in Baltimore, Boston, New York City, and St. Louis, following immune development, urban exposures, and asthma through age 7 and beyond.

Urechis unicinctus

Urechis unicinctus, the fat innkeeper worm or penis fish, is an East Asian echiuran spoon worm (Annelida, Urechidae) that filter-feeds via mucus nets in U-shaped burrows, hosts commensal crabs, tolerates sulfide, and is eaten in Korea, China, and Japan.