All articles starting with O
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Orchestra in the Agora of Athens
Orchestra in the Agora of Athens: the 6th-century BC performance area, also called Agora orchestra, at the center of the Athenian Agora, with a circular platform and wooden ikria stands, abandoned after their early 5th-century BC collapse in favor of the Theater of Dionysus.
Orchestra Super Mazembe
Orchestra Super Mazembe was a Congolese rumba band formed in Zaire in the late 1960s and based in Nairobi, whose 1977 hit "Kassongo" became a regional anthem.
Orchestral Manoeuvres in the Dark
Orchestral Manoeuvres in the Dark (OMD), English synthpop band formed 1978 on the Wirral by Andy McCluskey and Paul Humphreys; Kraftwerk-influenced, 14 albums from 1980 debut to Bauhaus Staircase (2023), hits Enola Gay and If You Leave.
Orchestrated objective reduction
Orchestrated objective reduction (Orch OR) is Penrose and Hameroff's quantum consciousness theory, proposing gravity-induced wavefunction collapse (Diósi–Penrose scheme) in neuronal microtubules; contested by Tegmark's decoherence calculations and not widely accepted.
Orchestre Kiam
Orchestre Kiam was a Congolese dance orchestra of the 1970s in Kinshasa, Zaire, named after its patron Verckys Kiamuangana and known for the 1976 hit "Kamiki".
Orchha (ओरछा)
Orchha (ओरछा), a historic town in Niwari district, Madhya Pradesh, on the Betwa River, was the Bundela dynasty capital 1531-1783, famed for Jahangir Mahal, Ram Raja Temple, and cenotaphs, and on India's UNESCO Tentative List since 2019.
Orchha State
Orchha State (ओरछा राज्य) was a Bundela Rajput princely state on the Betwa river in Bundelkhand, Madhya Pradesh, founded by Rudra Pratap Singh in the sixteenth century.
Orchid
Orchid (Orchidaceae): one of the largest flowering-plant families, over 700 genera and roughly 30,000 species on all continents except Antarctica; defined by bilateral flowers, dust-like mycorrhiza-dependent seeds, deceptive pollination, CITES protection, and major horticultural trade.
Orchid and Butterfly Valley
Orchid and Butterfly Valley (蝶谷幽兰) is a 7,208-square-meter orchid and butterfly garden in Fairy Lake Botanical Garden, Shenzhen, opened in 2009, with three sections conserving over 300 orchid species and attracting live butterflies.
Orchid Asia
Orchid Asia is a Hong Kong-based private equity and growth capital firm founded in 1993 that invests in expanding private companies in China and the wider Asia-Pacific region.
Orchid cultivation
Orchid cultivation is the horticultural practice of growing orchids, most of which are epiphytes or terrestrials, so they need chunky bark or moss instead of soil.
Orchid ecology and biogeography
Orchid ecology and biogeography is the study of where the orchid family grows and what threatens it; most of its 30,000 species are tropical epiphytes.
Orchid fleck dichorhavirus
Orchid fleck dichorhavirus (orchid fleck virus, OFV, Dichorhavirus orchidaceae) is a bipartite negative-sense RNA rhabdovirus causing chlorotic or necrotic spots in orchids worldwide, transmitted and replicated in Brevipalpus false spider mites.
Orchid mycorrhiza
Orchid mycorrhiza is the symbiosis between orchids and orchid mycorrhizal fungi (OMF), mainly rhizoctonias such as Tulasnella and Ceratobasidium, required by all orchids for seed germination, forming pelotons, and supporting autotrophic, mycoheterotrophic, and mixotrophic adult nutrition.
Orchid nothogenera and intergeneric hybrid genera
Orchid nothogenera are single-word names for hybrids between two or more orchid genera, such as × Doritaenopsis, governed by the ICN and registered with the RHS.
Orchid Pavilion Collection
The Orchid Pavilion Collection (蘭亭集, Lanting ji) is an anthology of poems from a 353 CE gathering hosted by calligrapher Wang Xizhi at the Orchid Pavilion in Shaoxing.
Orchid phytochemistry
Orchid phytochemistry is the study of the chemical compounds produced by orchids, including phenanthrenes, alkaloids, and vanillin; orchids are the plant kingdom's richest source of phenanthrenes.
Orchid pollination
Orchid pollination is the study of how the more than 29,000 orchid species transfer pollen in packaged pollinia, often deceiving pollinators instead of offering nectar rewards.
Orchid propagation
Orchid propagation is the human-managed reproduction of orchids by sterile seed culture, clonal micropropagation, and vegetative division, back-bulbs, and keikis, replacing natural germination that depends on mycorrhizal fungi.
Orchid Resort Dogashima
Orchid Resort Dogashima (らんの里堂ヶ島, Ran no Sato Dogashima) was an orchid garden in Nishiizu, Shizuoka, founded 1968 as Dogashima Western Orchid Center, reopened 2006, closed July 31, 2013; not the Dogashima onsen hotels.
Orchidaceae
Orchidaceae (orchids), one of the two largest flowering plant families with about 760 genera and 26,000 species, cosmopolitan except Antarctica, over 75% epiphytic, defined by resupinate zygomorphic flowers, a labellum, fused column, pollinia, and fungus-dependent microseeds.
Orchidland Surf
Orchidland Surf (Orchid Land Surf Shop) is a surf shop at 262 Kamehameha Ave in downtown Hilo, Hawaii, open since 1972, run by surfer-shaper Stan Lawrence, selling and renting boards, apparel, and gear.
Orchidopexy
Orchidopexy (or orchiopexy) is a surgical operation that moves an undescended testicle into the scrotum and fixes it there, the standard treatment for cryptorchidism in pediatric urology, ideally performed between 6 and 18 months of age.
Orchids of Africa
The orchids of Africa are the orchid species of continental sub-Saharan Africa and Madagascar, totaling over 2,000 species, with Central Africa richest and the chikanda tuber trade threatening many.
Orchids of Australia
The orchids of Australia are a native flora of roughly 1,700 to 2,000 species in about 116 genera, with 90 to 95% endemic and richest in the country's south-west.
Orchids of Europe
The orchids of Europe comprise about 1,000 species, subspecies, and varieties of Orchidaceae, concentrated in the Mediterranean, with high endemism, recent rapid speciation, and a quarter of assessed species threatened.
Orchids of Madagascar
The orchids of Madagascar are a highly endemic flora of about 1,000 species in 53 genera, famous for Darwin's 1862 prediction of a long-tongued hawkmoth pollinator.
Orchids of New Zealand
The orchids of New Zealand comprise about 117 species in 24 to 27 genera, mostly small terrestrial ground orchids, with greenhoods (Pterostylis) the largest genus.
Orchids of North America
The orchids of North America are the roughly 210 orchid species native north of Mexico plus about 2,670 Mesoamerican species, with richness rising steeply toward the tropics.
Orchids of South America
Orchids of South America covers the continent's orchid diversity: Colombia, Ecuador, and Brazil lead with thousands of species each, concentrated in the Andes and Atlantic Forest.