All articles starting with L
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Leptomeningeal carcinomatosis
Leptomeningeal carcinomatosis, also called leptomeningeal metastasis or neoplastic meningitis, is spread of cancer cells within the leptomeninges and subarachnoid space, affecting about 5% of cancer patients, most often from breast, lung cancer, or melanoma, diagnosed by CSF cytology and MRI.
Lepton
A lepton is an elementary particle of matter that does not feel the strong nuclear force; the six leptons include the electron, muon, tau, and their neutrinos.
Lepton AI
Lepton AI was a U.S.-based AI-inference cloud startup founded in 2023 by former Meta AI researchers Yangqing Jia and Junjie Bai, acquired by NVIDIA in April 2025.
Lepton universality
Lepton universality, or lepton flavor universality (LFU), is a Standard Model principle that the electron, muon, and tau couple identically to electroweak gauge bosons, differing only in mass.
Leptonic emission
Leptonic emission is high-energy radiation produced directly by relativistic leptons, chiefly electrons and positrons, through synchrotron radiation, bremsstrahlung, and inverse Compton scattering, contrasted with hadronic emission from pion decay.
Leptonychotes
Leptonychotes (Weddell seal genus) is a monotypic phocid seal genus, Leptonychotes weddellii, tribe Lobodontini, the southernmost living mammal, breeding on Antarctic fast ice, diving over 600 m, IUCN Least Concern.
Leptonycteris
Leptonycteris is a genus of three migratory, nectar-feeding bat species in the leaf-nosed bat family, native to arid North America from Arizona to Central America.
Leptopelis
Leptopelis (forest treefrogs, leaf-frogs) is a genus of about 56 arboreal frog species in Arthroleptidae, subfamily Leptopelinae, endemic to sub-Saharan Africa; axillary amplexus, eggs in burrows near water, cryptic species in the Albertine Rift and Ethiopia.
Leptophlebiidae
Leptophlebiidae, the prong-gilled mayflies, is a cosmopolitan Ephemeroptera family with about 140 genera and 640 species, forked nymphal gills lacking costal and anal ribs, and a contested internal classification now divided into eight subfamilies.
Leptoquark
A leptoquark is a hypothetical particle that couples to both a quark and a lepton, allowing the two to transform into each other; none has been observed.
Leptospermum
Leptospermum (tea trees) is a Myrtaceae genus of shrubs and small trees native from Indo-China to New Zealand, most diverse in Australia; type species mānuka (L. scoparium), split into five genera by 2023 revision.
Leptosphaeria
Leptosphaeria is a genus of dothideomycete fungi in Leptosphaeriaceae (Pleosporales), type species L. doliolum, established 1863; includes L. maculans, cause of blackleg stem canker of oilseed rape.
Leptospira
Leptospira, genus of aerobic spirochete bacteria (35 species; pathogenic, intermediate, saprophytic clades; over 250 serovars), causes leptospirosis, the most widespread zoonosis, about 1 million cases and 60,000 deaths yearly.
Leptospira interrogans
Leptospira interrogans, the pathogenic spirochete causing leptospirosis and Weil's disease; question-mark-shaped bacterium with 300+ serovars, spread via animal urine in contaminated water, about 1.03 million human cases yearly.
Leptospirosis
Leptospirosis, or Weil's disease in its severe icteric form, is a zoonotic spirochete infection caused by Leptospira, spread via animal urine in contaminated water; over 1 million cases and about 59,000 deaths occur yearly.
Leptosporangiate fern
Leptosporangiate ferns (Polypodiopsida) are ferns whose sporangia develop from a single cell with a one-layer wall and spore-flinging annulus; about 10,323 species in 44 families, homosporous except Salviniales, with a Cenozoic radiation.
Leptosporangium development
Leptosporangium development is the mode defining leptosporangiate ferns: a single superficial cell forms a stalked, one-cell-thick capsule with few spores and an annulus that flings them out.
Leptosynapta dolabrifera
Leptosynapta dolabrifera (Stimpson, 1855), the Snot Sea Cucumber, is a small synaptid sea cucumber from southern Australia, about 15 cm long, covered in sticky mucus, burrowing in soft sediments and feeding on sand and mud.
Leptothrix
Leptothrix (Kützing 1843) is a genus of gram-negative, sheathed, iron- and manganese-oxidizing bacteria in the order Burkholderiales; type species Leptothrix ochracea; distinct from the spider genus Leptothrix Menge 1869.
Leptotyphlops
Leptotyphlops (threadsnakes, slender blind snakes) is a genus of tiny burrowing African snakes in Leptotyphlopidae, Fitzinger 1843, type species Typhlops nigricans; once held nearly the whole family, reduced to 23 eastern and southern African species after the 2009 molecular revision.
Lepu Biopharma
Lepu Biopharma (乐普生物) is a Shanghai biopharmaceutical company founded by Dr. Pu Zhongjie in 2018 and listed on the Hong Kong Stock Exchange since 2022, focused on antibody-drug conjugates for cancer.
Lepus (constellation)
Lepus, meaning the Hare in Latin, is a constellation south of the celestial equator just below Orion's feet, cataloged by Ptolemy in the 2nd century.
LeQuint Allen
LeQuint Allen Jr. (born 2004) is an NFL running back for the Jacksonville Jaguars, drafted 236th overall in 2025. Syracuse record-holder for receptions by a running back (119) with 2,359 career rushing yards.
Lera Abova
Lera Abova (Лера Абова), born Valeria Smirnova, 1992, Slavgorod, Siberia, is a Russian-German model and actress: David Sims discovery, Vogue covers, film debut as Maude in Anna (2019), and Nico Robin in Netflix's One Piece season 2.
Lera Boroditsky
Lera Boroditsky is a cognitive psychologist and professor at the University of California, San Diego, known for experiments on how language shapes habitual thought about time and color.
Leray spectral sequence
The Leray spectral sequence is a spectral sequence, introduced by Jean Leray in 1945 alongside sheaf theory, that computes the cohomology of a space from a continuous map's fibers.
Lercanidipine
Lercanidipine (Zanidip) is a lipophilic third-generation dihydropyridine calcium channel blocker for mild to moderate hypertension, dosed 10–20 mg once daily; approved in Europe and many countries but never FDA approved in the United States.
Lercoul
Lercoul is a commune and archaeological site in the Ariège department of the French Pyrenees, known for an ancient iron-smelting workshop excavated in the Forêt-Royale.
Lerdelimumab
Lerdelimumab (CAT-152, Trabio) is a human IgG4 monoclonal antibody neutralizing TGF-β2, developed by Cambridge Antibody Technology and Genzyme to prevent scarring after trabeculectomy; phase III trials showed no benefit over placebo and development was discontinued.
Lerer Hippeau
Lerer Hippeau is a New York-based early-stage venture capital firm founded in 2010 by Ben Lerer, Kenneth Lerer, and Eric Hippeau, investing at pre-seed and seed stages.