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Mostrando ítems 171-180 de 1414
Patrones de coloración en Hymenoptera: su origen, evolución y posible función en miras a la aplicación biomimética
(2020-04-28)
El presente estudio proporciona la primera caracterización física y funcional del patrón negro-naranja-negro (BOB) que se encuentra en avispas parasitoides de muy pequeño tamaño (3-10 mm). Aunque se había reportado previamente ...
Reduced activity of Arabidopsis chromosome-cohesion regulator gene CTF7/ECO1 alters cytosine methylation status and retrotransposon expression
(2015-05-01)
Multicellular organisms such as higher plants require timely regulation of DNA replication and cell division to grow and develop. Recent work in Arabidopsis has shown that chromosome segregation during meiosis and mitosis ...
Additions to the Genus Bactris (Arecaceae)of Mesoamerica
(2000)
Two new endemic species of Bactris, found in the understorey of humid forest on the Pacific Coast of Costa Rica, are described and illustrated. Bactris ana-juliae is 1.8-3.0 m tall, and B. herrerana is 2.0-3.0 m tall.
Effect of fragmentation on the Costa Rican dry forest avifauna
(2016)
Deforestation and changes in land use have reduced the tropical dry forest to isolated forest patches in northwestern Costa Rica. We examined the effect of patch area and length of the dry season on nestedness of the entire ...
A new species of Eurystyles (Orchidaceae: Spiranthinae) from Costa Rica
(2020)
Eurystyles comprises about 23 species ranging from Mexico to northernArgentina. Six species are recognized in Mexico and Central America and three in Costa Rica. A new species, named E. uxoris, is here described and ...
Evaluation of pharmacological therapies used in Costa Rica in patients with metastatic gastric cancer: a retrospective study
(2019-01-18)
Background: Gastric cancer is one of the leading causes of cancer death worldwide. Surgery is regarded as the best curative treatment option for gastric cancer; however, a high proportion of cases are diagnosed at advanced ...
Natural History and Larval Behavior of the parasitoid Zatypota petronae (Hymenoptera: Ichneumonidae)
(2007)
The koinobiont ectoparasitoid Zatypota petronae Gauld (Ichneumonidae) parasitizes medium-sized immatures of the cobweb spider Theridion evexum Keyserling (Theridiidae). Zatypota petronae apparently attacks the spider inside ...
Neutralization of proteolytic and hemorrhagic activities of Costa Rican snake venoms by a polyvalent antivenom
(1985)
The polyvalent antivenom produced at the Instituto Clodomiro Picado, Costa Rica, was tested for its capacity to neutralize proteolytic and hemorrhagic activities of ten Costa Rican crotaline venoms. In experiments with ...
Population and genetic structure of two dioecious timber species Virola surinamensis and Virola koschnyi (Myristicaceae) in southwestern Costa Rica
(2014)
Selective logging regulations generally fail to account for sex ratios, sex size distribution, spatial patterns and genetic structure in dioecious timber species. Furthermore, sympatric congeneric dioecious tropical species ...
Fungi in aquatic ecosystems
(2019-03)
Fungi are phylogenetically and functionally diverse ubiquitous components of almost all ecosystems on Earth, including aquatic environments stretching from high montane lakes down to the deep ocean. Aquatic ecosystems, ...