All articles starting with R
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Rethmann
Rethmann, also known as the Rethmann Group, is a German family-owned holding company founded in Selm in 1934, parent of REMONDIS, Rhenus, SARIA, and Transdev.
Rethmann family
The Rethmann family is a German business family that wholly owns Rethmann SE & Co. KG in Selm, with recycling, logistics, animal by-products, and mobility divisions.
Réti Opening
Réti Opening (Zukertort Opening), chess opening starting 1.Nf3, often 1.Nf3 d5 2.c4 (Réti Gambit), ECO A04–A09; hypermodern flank opening named after Richard Réti, famous for beating Capablanca at New York 1924.
Reticle
A reticle is a patterned glass or quartz master plate used in photolithography to print one layer of an integrated circuit onto a wafer, broadly interchangeable with the term photomask.
Reticular cell
Reticular cell (reticulum cell), Cell Ontology CL:0000432: a fibroblast that synthesizes collagen to make reticular fibers (mainly type III collagen), providing stromal support in spleen, lymph nodes, kidney, and bone marrow; includes fibroblastic reticular cells that build immune-cell conduits.
Reticular chemistry
Reticular chemistry, coined by Omar Yaghi in 2003, is the linking of molecular building blocks by strong bonds into crystalline frameworks such as MOFs and COFs.
Reticular dysgenesis
Reticular dysgenesis, also called AK2 deficiency or De Vaal disease, is the most severe form of severe combined immunodeficiency: autosomal recessive AK2 mutations cause agranulocytosis, T and NK lymphocytopenia, and sensorineural deafness, fatal without stem cell transplantation.
Reticular dystrophy of the retinal pigment epithelium
Reticular dystrophy of the retinal pigment epithelium (dystrophia reticularis laminae pigmentosae retinae, Sjögren 1950) is a rare inherited pattern macular dystrophy with a bilateral fishnet RPE pigment pattern, adult onset, good visual prognosis, PRPH2 linkage.
Reticular erythematous mucinosis
Reticular erythematous mucinosis (REM syndrome, midline mucinosis) is a rare chronic skin mucinosis causing reticulated red papules and plaques on the midline chest and upper back of middle-aged women, treated with antimalarials.
Reticular formation
Reticular formation (formatio reticularis): brainstem neuron network from midbrain to medulla regulating arousal, consciousness, sleep-wake cycles, and autonomic functions; source of the ascending reticular activating system (RAS) identified by Moruzzi and Magoun in 1949.
Reticular pseudodrusen
Reticular pseudodrusen, or subretinal drusenoid deposits, are yellowish subretinal lesions above the retinal pigment epithelium in age-related macular degeneration, strongly predicting progression to geographic atrophy and detectable only with multimodal imaging.
Reticularia
Reticularia names two accepted genera: a slime mold genus (Reticularia Bull. 1788, type R. lycoperdon, family Reticulariaceae) and an extinct Carboniferous brachiopod genus (Reticularia M'Coy 1844, family Reticulariidae), a homonymy case across nomenclatural codes.
Reticulate acropigmentation of Kitamura
Reticulate acropigmentation of Kitamura (RAK, RAPK) is a rare autosomal dominant skin hyperpigmentation disorder caused by ADAM10 loss-of-function mutations, producing reticulate, depressed brown macules on the hands and feet without hypopigmentation.
Reticulated python
Reticulated python, Malayopython reticulatus (formerly Python reticulatus), ular sawa batik: the longest snake species, reaching 8-10 m, native from India to the Philippines and Indonesia, CITES Appendix II, IUCN Least Concern.
Reticulocyte
Reticulocyte: an immature anucleate red blood cell that matures in about 1-2 days; also called proerythrocyte. Its count (normal ~0.8-0.9%, ARC 25,000-75,000/µL) gauges marrow erythropoietic activity in anemia, with IRF and CHr parameters.
Reticulocyte Count
Reticulocyte count (retic count) is a blood test measuring immature red blood cells to gauge bone marrow erythropoietic activity; used in anemia workup, with manual microscopy and automated flow cytometry methods and RPI correction.
Reticulon
Reticulons (RTNs, RTN1–RTN4 in mammals; RTN4 also called Nogo) are eukaryotic membrane proteins with a C-terminal reticulon homology domain that shape and stabilize curved endoplasmic reticulum tubules and are implicated in neurodegenerative disease and viral replication.
Reticulosa
Reticulosa (Reid, 1958) is an extinct order of thin-walled, hexactin-built Paleozoic sponges placed in Hexactinellida but now considered paraphyletic; it dominated Cambrian–Silurian offshore communities, with Dictyospongiidae persisting into the Carboniferous.
Reticulum II
Reticulum II, or Ret II, is an ultra-faint dwarf galaxy orbiting the Milky Way, discovered in 2015 in Dark Energy Survey imaging and about 98,000 light-years from Earth.
ReTIDES trial
ReTIDES (Regional Expansion of TIDES), NCT00119028, was a VA implementation project spreading the TIDES collaborative care model for depression to new VA networks, later marked withdrawn with zero enrollment.
Retief party massacre
The Retief party massacre (Ukubulwa kweVuzani) was the killing of Voortrekker leader Piet Retief and about 100 companions at the Zulu royal stronghold uMgungundlovu in 1838.
Retief–Dingane treaty
The Retief–Dingane treaty is an 1838 deed recording Zulu king Dingane's cession of Natal to Piet Retief and his Voortrekkers, who were killed days later.
Retifanlimab
Retifanlimab (Zynyz, INCMGA00012) is a humanized IgG4 anti-PD-1 checkpoint inhibitor by Incyte, FDA-approved for Merkel cell carcinoma (2023) and anal canal squamous cell carcinoma (2025).
Retiform hemangioendothelioma
Retiform hemangioendothelioma (RH), a rare intermediate-malignancy vascular tumor first delineated by Calonje in 1994, forms slow-growing hobnail-lined arborizing skin lesions of the distal extremities; it recurs locally in about 50-60% of cases but rarely metastasizes.
Retiming (digital circuits)
Retiming is a sequential circuit optimization technique that relocates registers across combinational logic, reducing clock period or register count while preserving the circuit's functional behavior.
Retina
The retina is the light-sensitive neural tissue lining the back of the eye, containing rods and cones plus bipolar, horizontal, amacrine, and ganglion cells; the fovea is rod-free with peak cone density, and OCT imaging and AAV gene therapy are central clinical advances.
Retina bipolar cell
Retinal bipolar cells are retinal interneurons relaying photoreceptor input to ganglion cells; about 12 primate and 13+ mouse types, split into ON (mGluR6) and OFF pathways.
Retina display
Retina display, Apple's marketing term for screens whose pixels are too small to see individually at typical viewing distance, was introduced with the iPhone 4 in June 2010.
Retina horizontal cell
Retina horizontal cells are inhibitory interneurons in the inner nuclear layer that feed back to photoreceptors and forward to bipolar cells, creating center-surround receptive fields; primates have H1 and H2 types, mice one, zebrafish four.
Retinal
Retinal (11-cis-retinal), the aldehyde of vitamin A, is the universal light-absorbing chromophore of rhodopsin and cone pigments; photoisomerized to all-trans and regenerated by the RPE65 visual cycle and a Müller-cell cone cycle.