All articles starting with L
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Long-beaked echidna
Long-beaked echidnas (Zaglossus) are three egg-laying monotreme species of New Guinea: Z. bruijnii, Z. bartoni, and Z. attenboroughi. Larger than the short-beaked echidna, they eat earthworms and larvae and are critically endangered except Z. bartoni.
Long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency
LCHAD deficiency, also called long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency, is a rare autosomal recessive HADHA-related fatty acid oxidation disorder causing hypoketotic hypoglycemia, cardiomyopathy, retinopathy, neuropathy, and maternal AFLP/HELLP, treated with fasting avoidance and MCT diet.
Long-chain alkylphenols
Long-chain alkylphenols are man-made, estrogen-like phenols bearing long alkyl chains, chiefly octylphenol and nonylphenol, which make up over 95 percent of the alkylphenol market and are used mainly as surfactant intermediates.
Long-chain specific acyl-CoA dehydrogenase
Long-chain specific acyl-CoA dehydrogenase (LCAD), encoded by ACADL at 2q34, is a mitochondrial enzyme of fatty acid beta-oxidation; no confirmed human LCAD deficiency exists, patients once labeled LCAD-deficient have VLCAD deficiency.
Long-chain-fatty-acid—CoA ligase
Long-chain-fatty-acid—CoA ligase (ACSL, long-chain acyl-CoA synthetase) activates C12-C20 fatty acids to acyl-CoA via ATP and CoA. Five mammalian isoforms (ACSL1, 3, 4, 5, 6) differ in substrate preference, location, and roles in ferroptosis and cancer.
Long-context LLMs
Long-context LLMs are large language models trained to process very large context windows, which grew from 4K-8K tokens in 2022-2023 to 1M-2M tokens by 2026.
Long-course chemoradiotherapy
Long-course chemoradiotherapy, also called long-course chemoradiation, is a neoadjuvant treatment for locally advanced rectal cancer combining about five to six weeks of pelvic radiotherapy with fluoropyrimidine chemotherapy before surgery.
Long-distance calling
Long-distance calling is telephone communication between exchanges or countries outside the caller's local calling area, once billed per minute by distance and later folded into internet-based phone service.
Long-distance relationship
Long-distance relationship (LDR): a romantic partnership between geographically separated partners, also called non-proximal relationship; distinguished from geographically close relationships by mediated communication, visits, similar satisfaction but equal breakup rates.
Long-distance running
Long-distance running covers athletics events over 3000 m: 5000 m, 10,000 m, half marathon, and the 42.195 km marathon. Key facts include Sawe's 1:59:30 first official sub-2-hour marathon, injury rates, and mortality benefits.
Long-distance swimming
Long-distance swimming, or marathon swimming, is open water swimming of 10 km or longer, shore to shore with no supportive contact; governed by WOWSA and World Aquatics rules, with thermal risk and ratified courses like the English and Catalina channels.
Long-exposure photography
Long-exposure photography is a technique that holds the shutter open for seconds to hours, recording motion as blur or light trails, first a necessity of slow early films and now a creative tool.
Long-haul trucking
Long-haul trucking is the segment of road freight in which drivers move cargo long distances in tractor-trailers, sleeping away from home most nights under federal hours-of-service rules.
Long-Horned Antelope
Long-horned antelope is a descriptive name for antelope with very long horns, chiefly the scimitar-horned oryx (Oryx dammah) of the Sahara, also applied to the saola, nilgai, and eland.
Long-legged buzzard
Long-legged buzzard (Buteo rufinus, Cretzschmar 1829), also called Buse feroce, is a large Accipitridae raptor of arid steppes from SE Europe to Central Asia, 50-65 cm, wingspan 126-155 cm, IUCN Least Concern, with disputed cirtensis taxonomy.
Long-lived particles
Long-lived particles (LLPs) are particles that are stable or live long enough for their decays to be experimentally distinguishable in time or position from where they were produced.
Long-nosed horned frog
Long-nosed horned frog (Pelobatrachus nasutus, formerly Megophrys nasuta), also called Malayan horned frog: a large leaf-mimicking megophryid frog of Sumatra, Borneo, Singapore, and peninsular Malaysia-Thailand; females to 120 mm, IUCN Least Concern but Critically Endangered in Singapore.
Long-period radio pulsars
Long-period radio pulsars are compact stars, neutron stars or white dwarfs, that emit radio pulses every tens of seconds to hours, beyond the classical pulsar range.
Long-period radio transient
A long-period radio transient is a Galactic source of repeating, strongly polarized radio bursts on periods of minutes to hours, identified in 2022 with about a dozen members known.
Long-period variable
A long-period variable is a pulsating red giant or supergiant star, mostly on the asymptotic giant branch, whose brightness changes over periods of tens to more than a thousand days.
Long-Qing Chen
Long-Qing Chen is a materials scientist at Pennsylvania State University known for developing the phase-field method, a computational approach for predicting the microstructure and properties of engineering materials.
Long-Range Hypersonic Weapon
The Long-Range Hypersonic Weapon, known as Dark Eagle and abbreviated LRHW, is a US Army ground-launched hypersonic boost-glide missile with a reported range of 1,725 miles.
Long-range reconnaissance patrol
Long-range reconnaissance patrol (LRRP), also called LRP: small US Army teams infiltrating deep enemy territory for intelligence, shaped in 1950s Europe, prominent in Vietnam 1966-72, later becoming Ranger companies, LRS detachments, and today's MFRCs.
Long-range Wi-Fi
Long-range Wi-Fi extends wireless networking well beyond indoor range, through the sub-1 GHz Wi-Fi HaLow standard (IEEE 802.11ah) for IoT, or directional 2.4 and 5 GHz point-to-point links.
Long-read sequencing
Long-read sequencing reads individual DNA or RNA molecules over kilobases to megabases, unlike 100–300 bp short reads, and enabled the first complete human genome assembly.
Long-run average cost curve
The long-run average cost curve shows the lowest attainable cost per unit at each output when all inputs can be varied, drawn as the envelope of short-run curves.
Long-slit spectroscopy
Long-slit spectroscopy is an astronomical observing technique that disperses light from a narrow strip of sky, recording a separate spectrum for each point along the slit.
Long-tailed tit
The long-tailed tit (Aegithalos caudatus) is a tiny Eurasian songbird weighing about 7.8 grams, with a tail longer than its body and a domed nest of moss, spider silk, and feathers.
Long-tailed weasel
Long-tailed weasel (Neogale frenata, formerly Mustela frenata): a small mustelid carnivore with the largest distribution of any Western Hemisphere mustelid, from southern Canada to northern South America; white winter coat in the north, black-tipped tail over 44% of head-body length, Least Concern but declining regionally.
Long-Term Capital Management
Long-Term Capital Management (LTCM) was a Greenwich, Connecticut hedge fund founded by John Meriwether in 1994, whose 1998 collapse forced a $3.625 billion bank rescue.