Browsing Artículos científicos by Title
Now showing items 332-351 of 555
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Induction of ovarian maturation and spawning by combined treatment of serotonin and a dopamine antagonist, spiperone in Litopenaeus stylirostris and Litopenaeus vannamei
(Universidad Nacional, Costa Rica, 2004)The study was designed to develop a reliable technique for inducing ovarian maturation and spawning in Litopenaeus stylirostris and Litopenaeus vannamei, as an alternative to the traditional and destructive eyestalk ... -
Induction of sperm activation in open and closed thelycum penaeoid shrimps
(Aquaculture vol.216 no.1-4 371-381 2003, 2003)A modified egg water (EW) technique for in vitro induction of sperm activation was applied to Trachypenaeus byrdi, Xiphopenaeus riveti (closed thelycum shrimps), and Litopenaeus occidentalis (open thelycum) from a tropical ... -
Influence of oceanographic conditions on nesting abundance, phenology and internesting periods of east Pacific green turtles
(Springer Verlag, 2019)Sea turtles are migratory animals that travel from foraging grounds to specifc nesting beaches every few years and that, therefore, can be infuenced by oceanographic conditions in several diferent habitats. We assessed ... -
Influencia de las competencias emocionales de docentes de Ciencias Naturales en la adquisición de las habilidades emocionales de los estudiante. El caso de un colegio secundario en Costa Rica
(Facultad de Psicología de la Universidad Michoacana de San Nicolás de Hidalgo, 2015)Este artículo socializa los resultados de una investigación sobre la influencia que tienen las competencias emocionales (conciencia, regulación y autonomía) de algunos docentes de física, química y biología, en la manifestación ... -
Influencia del pez León (Pterois miles y Pterois volitans) en la cadena de valor de la pesca artesanal, Caribe sur de Costa Rica
(Universidad Estatal a Distancia (Costa Rica), 2019-08-23)“Lionfish (Pterois miles and Pterois volitans) influence on the artisanal fishing value chain, Southern Caribbean of Costa Rica”. Introduction: The “Lionfish” are actually two invasive species that occur in several parts ... -
Infuence of soil characteristics on physiological and growth responses of Cytharexyllum myrianthum Cham. (Verbenaceae) to fooding
(Springer Science and Business Media Deutschland GmbH, 2020-10-27)The success of watershed riparian forest restoration programs can be afected by the selection of plant species tolerant to fooding and soil types that occur along water courses. We evaluated physiological and growth ... -
Los inicios y primeros logros de la red UNA STEM
(Universidad de la Laguna (España), 2022)La Red UNA STEM es una propuesta de varias personas académicas de la Facultad de Ciencias Exactas y Naturales y Facultad de Ciencias de la Tierra y el Mar de la Universidad Nacional (UNA), que tiene como objetivo permear ... -
Insecticidal activity of ethanolic plant extracts on Aedes aegypti larvae
(Universidad Nacional (Costa Rica), 2023-06-01)The objective of this study was to determine the larvicidal activity against A. aegypti of ethanolic extracts of plants commonly found in Costa Rica. [Methodology] Larvicidal activity of ethanolic extracts of plants was ... -
Intensive Rearing of Juveniles of cichlasoma managuense (Günther 1869) in recirculated systems
(Universidad Nacional, Costa Rica, 1991-01-01)The growth performance of guapote juveniles in recirculated systems from spawning to a mean weight of about 3 gramms is described. Culture began with a 15 days nursing phase with either first instar-nauplii or fresh ... -
Interaction of bacteria and male reproductive system blackening disease of captive Penaeus setiferus
(Elsevier, 1993)The genital apparatus of male penaeid shrimp, Penaeus sett’ferus, blackens with resulting detrimen tal effects ton mating for production of larvae when animals are kept in controlled maturation/repro duction situations. A ... -
Isolation and characterization of partial insulin-like androgenic gland hormone gene from distal terminal ampoules of three marine shrimp Penaeus species from the Eastern Pacific
(2018)The expansion of the shrimp industry depends on scientific advances related to the understanding of reproductive endocrinology that allows the development of aquaculture programs based on biotechnology. An insulin ... -
Isolation and partial purification of a hemolytic sphingomyelin-inhibitable fraction from the sea anemone Anthopleura nigrescens
(2014-03)Actinoporins are highly hemolytic pore-forming proteins with a molecular mass of around 20 kDa and high affinity for sphingomyelin-containing membranes. On the crude extract of the sea anemone Anthopleura nigrescens, the ... -
Isolation of ammonium- and nitrite-oxidizing bacterial strains from soil, and their potential use in the reduction of nitrogen in household waste water
(Universidad de Costa Rica, 2017-12-01)Currently, nitrogen has become the main element of water pollution, causing riverine, lacustrine and coastal eutrophication. The continuous contamination of aquifers and the absence of planned water resource utilization, ... -
Isolation on a remote island: genetic and morphological differentiation of a cosmopolitan odonate
(Nature Publishing Group, 2019-06-01)Although low levels of genetic structure are expected in highly widespread species, geographical and/or ecological factors can limit species distributions and promote population structure and morphological differentiation. ... -
Isotopic composition in precipitation and groundwater in the northern mountainous region of the Central Valley of Costa Rica
(Taylor & Francis, 2016)The linkage between precipitation and recharge is still poorlyunderstood in the Central America region. This study focuses onstable isotopic composition in precipitation and groundwater in the northern mountainous region ... -
Landscape analysis for the American crocodile Crocodylus acutus (Reptilia: Crocodilidae) in northwestern Costa Rica
(Instituto de Biología de la UNAM (México), 2022-10-18)Northwest Costa Rica has the largest crocodile population in the country, but it is also an important area of the human population growth, tourism, crops, and aquaculture, that have generated great changes in the region. ... -
Larvae of the Costa Rican Hetaerina (Odonata: Calopterygidae) with comments on distribution
(Royal Entomological Society, 1993)The larvae of seven of the nine Costa Rican species of Hetaerina (H.capitalis, H.cruentata, H. fuscogutfata, H. majuscula, H. miniata, H. occisa and H. titia) were identified by matching their Cellulose Acetate Gel ... -
Late onset autosomal dominant Charcot– Marie–Tooth 2 neuropathy in a Costa Rican family
(W.S. Maney & Son Ltd., 2009)Objective: To describe the clinical, electrophysiologic and morphologic features of a Costa Rican family with an autosomal dominant inherited Charcot–Marie–Tooth (CMT) neuropathy. Methods: The field study took place in ... -
Latitudinal regionalization of epibenthic macroinvertebrate communities on rocky reefs in the Gulf of California
(Marine Biology Research vol.12 no.4 389-401 2016, 2016-04-27)We report on a latitudinal pattern in the structure and species composition of epibenthic macroinvertebrate communities on rocky reefs along a gradient of eight degrees of latitude in the Gulf of California. We provide ... -
Leaf life span spectrum of tropical woody seedlings: effects of light and ontogeny and consequences for survival
(Oxford University Press, Annals of Botany Company, 2013-03-26)Background and AimsLeaf life span is widely recognized as a key life history trait associated with herbivory resistance, but rigorous comparative data are rare for seedlings. The goal of this study was to examine how light ...