Browsing Facultad de Ciencias Exactas y Naturales by Title
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Green Solvents in Carbohydrate Chemistry: From Raw Materials to Fine Chemicals
(American Chemical Society, 2015)In recent decades, there has been an increasing effort to reduce the use of fossil fuels and oil derivatives, to decrease environmental pollution, and to counteract global warming. The use of biomass as raw material is ... -
Green Synthesis of Gold and Silver Nanoparticles from Plant Extracts and Their Possible Applications as Antimicrobial Agents in the Agricultural Area
(MDPI AG, 2020-09-07)Currently, metal nanoparticles have varied uses for different medical, pharmaceutical, and agricultural applications. Nanobiotechnology, combined with green chemistry, has great potential for the development of novel and ... -
Groundwater age and recharge processes in a tropical volcanic aquifer
(Universidad Nacional (Costa Rica), 2019)La recarga de agua subterránea en acuíferos volcánicos altamente fracturados sigue siendo poco conocida en los trópicos húmedos. El rápido crecimiento demográfico y los cambios no regulados en el uso de la tierra dieron ... -
Groundwater and surface water connectivity within the recharge area of Guarani aquifer system during El Niño 2014–2016
(Wiley & Sons, 2018)Recharge areas of the Guarani Aquifer System (GAS) are particularly sensitive and vulnerable to climate variability; therefore, the understanding of infiltration mechanisms for aquifer recharge and surface run‐off generation ... -
Groundwater flow modeling using iMOD for Barva and Colima aquifers in the Central Valley of Costa Rica: validation of a conceptual model using tracer data
(Universidad Nacional de Salta, 2018)A stationary numerical model of groundwater flow was developed using iMOD to better understand the recharge processes within Barva and Colima aquifers (BCS), located in the northwestern region of the Central Valley of Costa ... -
Groundwater recharge mechanisms inferred from isoscapes in a complex tropical mountainous region
(AGU Publications, 2016-05-23)Stable isotope variations and groundwater recharge mechanisms remain poorly understood across the tropics, particularly in Central America. Here stable isotopes (δ18O and δ2H) in groundwater, surface water, and rainfall ... -
Growth and alkaline digestive proteases activity of Parachromis dovii larvae fed live prey and formulated diets with different protein sources
(Universidad Técnica de Manabí (Ecuador), 2022-07-16)Parachromis dovii is a carnivorous cichlid fish from Central America, which easily accepts formulated feeds since exogenous feeding starts; however, its larval growth is lower than that obtained using live food. For this ... -
Growth and feed utilization of Dow cichlid (Cichlasoma dovii) larvae fed Artemia nauplii
(Universidad de Costa Rica (Costa Rica), 1995-12-01)Growth and feed utilization of Dow cichlid larvae (Cichlasoma dovii) fed with Artemia nauplii during the [lISt 12 days are assessed and compared with the growth of the larvae of the jaguar cichlid (Cichlasoma managuense). Growth ... -
Growth and fillet yield in recirculation systems of Lobotes pacificus (Perciformes: Lobotidae), a species with aquaculture potential
(Universidad Nacional (Costa Rica), 2019-07)The genus Lobotes extends across tropical and subtropical areas of oceans such as the Atlantic and the Pacific; it is extracted in artisanal fisheries, and its aquaculture production technology is still under investigation. ... -
Growth and hydrogen production by three Chlamydomonas strains cultivated in a commercial fertilizer
(Elsevier Ltd, 2019-04-19)In the present investigation, we report the growth and hydrogen production of two wild type Chlamydomonas reinhardtii strains isolated from a tropical oxidation pond in Costa Rica. The performance of these two new isolates ... -
Growth and photosynthetic performance of five tree seedlings species in response to natural light regimes from the Central Pacific of Costa Rica
(Universidad de Costa Rica, 2013)Growth and photosynthetic performance of five seedlings of tree species in response to natural light regimes in the Central Pacific of Costa Rica. Environmental heterogeneity mostly dominated by differing light regimes ... -
Growth of Jaguar Cichlid (Cichlasoma managuense) juveniles at different oxygen levels
(Universidad Nacional, Costa Rica, 1992-01-01)The dependence of growth on the dissolved oxygen level was analyzed un juveniles of the guapote tigre, Cichlasoma managuense, in a recirculated system. The guapote tigre is relatively tolerant to low oxygen levels, averaging ... -
Growth of Oreochromis aureus fed with diets containing graded levels of coffee pulp and reared in two culture systems
(Aquaculture vol.217 no.1-4 275-283 2003, 2003)A study was conducted to compare growth and feed utilization of Oreochromis aureus fed graded levels of coffee pulp (CoP) and reared in aquaria or in pens. Diets contained 0, 130, 260 and 390 g kg 1 of oven-dried CoP. ... -
Growth of pacific snook (Centropomus nigrescens) juveniles at different salinities
(Universidad Nacional (Costa Rica), 1995-09-21)Se evaluó el crecimiento de juveniles del róbalo del Pacífico, Centropomus nigrescens con salinidades de 0, 18 y 36 ppt. No hubo diferencias estadísticas significativas ni en el crecimiento ni en el factor de conversión. ... -
Growth performance of Colossoma macropomum (Cuvier) juveniles at different feed rations
(Wiley & Sons, 1992)Growth performance, feed utilization and changes in body composition of Colossoma macropomum (Cuvier) juveniles — in the weight range 2 to 200 g — fed an artificial high protein diet, have been analysed against feed ... -
Growth, feed utilization and nutrient digestibility in tilapia fingerlings (Oreochromis aureus Steindachner) fed diets containing bacteria-treated coffee pulp
(Universidad Nacional, Costa Rica, 2002)The effectiveness of bacteria treated-coffee pulp (BT-CoP) in fish diets was evaluated in a feeding trial with Oreochromis aureus (Steindachner) fingerlings. Five diets were formulated to contain 0%, 6%, 12%, 18% and 24% ... -
Guía de identificación de plántulas y semillas para las especies forestales más utilizadas en viveros de Costa Rica
(Universidad Nacional (Costa Rica), 2004)En nuestro país la explotación sin ninguna mediada o medio de motivación ha venido en aumento durante los últimos años, muchas especies se encuentran en peligro de extinción debido a esto (Jiménez 1999). Se ha venido ... -
Guía para la Automatización del Plan de Pensiones del Fondo de Ahorro de Recope
(Universidad Nacional (Costa Rica), 1999)La investigación se realizó en la Sección de Cómputo del Fondo de Ahorro de Recope. Se implementó una Guía para la automatización del Plan de Pensiones, tomando como base las metodologías Análisis Estructurado, Prototipos ... -
Guía Rápida para Elaborar Planes de Preparativos y Respuesta ante Emergencias por Tsunamis para Hoteles y Cabinas
(Comisión Nacional de Prevención de Riesgos y Atención de Emergencias (CNE), 2020-05)Este documento se enfoca en tsunamis, buscar facilitar a hoteles y cabinas la aplicación de la Norma de Planes de Preparativos y Respuesta ante Emergencias para Centros Laborales o de Ocupación Pública. Requisitos. ... -
Habilidades blandas y científicas que se potencian en los estudiantes que participan de los procesos de entrenamiento en las Olimpiadas Costarricenses de Ciencias Biológicas (2015-2021)
(Universidad Nacional (Costa Rica), 2022)Esta investigación tuvo como objetivo analizar las habilidades blandas (esenciales o transversales) y científicas que se potencian en estudiantes que participan de los procesos de entrenamiento en las Olimpiadas ...