Browsing Artículos científicos by Title
Now showing items 190-209 of 226
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Potent CYP3A4 Inhibitors Derived from Dillapiol and Sesamol
(American Chemical Society 4, 6, 10915–10920 2019, 2019)Synthesis of 50 analogues of the natural insecticide synergists, dillapiol and sesamol, is reported. These were evaluated as potential insecticide synergists based on their inhibition of human CYP3A4. The most potent ... -
Preface to Stable isotopes in hydrological studies in the tropics: ecohydrological perspectives in a changing climate
(Wiley & Sons, 2019)Tropical regions (comprised between the Tropics of Cancer and Capricorn, 23.5°N to 23.5°S) cover approximately 36% of the Earth's landmass. They are home to 40% of the world's population, which is projected to increase ... -
Preliminary inventory of atmospheric emissions (SO2, NOx and TSP) from different industrial sectors in Costa Rica
(Universidad Nacional (Costa Rica), 2021-07-31)El uso de diversos combustibles, el incremento de la urbanización, y el desarrollo económico, han influido en la generación de contaminantes atmosféricos, tales como los NOx (óxidos de nitrógeno), el SO2 (dióxido de azufre) ... -
Producción de pescado seco-salado utilizando secadores solares
(Universidad Nacional (Costa Rica), 1986-01-01)La técnica de seco-salado de pescado es un método de preservación efectivo, rápido y barato que se ha utilizado durante cientos de años controlando la temperatura y la concentración de sal en proteínas como el pescado por ... -
Química y actividad fisiológica de metabolitos secundarios presentes en el género Amyris (Rutaceae)
(Universidad Nacional [Costa Rica], 1986-01-01)La familia Rutaceae comprende 1.600 especies agrupadas en 150 géneros, que viven en zonas templadas y tropicales del mundo, siendo numerosas en el sur de África y en Australia (Engler, 1964). La mayoría son plantas ... -
Rainfall, groundwater, and surface water isotope data from extreme tropical cyclones (2016-2019) within the Caribbean Sea and Atlantic Ocean basins
(Elsevier, 2020-06)Under a changing climate, projections estimate that over the next thirty years, extreme Tropical Cyclones (TCs) will increase in frequency, with two to three times more Category 4 and 5 hurricanes in the Atlantic basin ... -
Recovery of acetate by anion exchange with consecutive CO2-expanded methanol desorption: A model-based approach
(Elsevier BV, 2018-04-07)Production of bio-based acetate is commonly hindered by the high costs of the downstream processing. In this paper, a model is developed to describe a new method that recovers acetate salts using anion exchange resins, and ... -
Remote Piloting UAS in Extreme Environments with Challanging Climatic Conditions - An Overview of Modern UAS Capabilities in the Field of Volcanology, Geosciences, Atmospheric Chemistry and Interplanetary Exploration
(ADVANCED ENGINEERING DAYS (AED), 2022-09)Unmanned Aerial Systems have recently had advanced payloads configured by engineers for various atmospheric sampling experiments and have been proven a successful and innovative technology. Climatic stability in volcanic ... -
Renewable fatty acid ester production in Clostridium
(Nature Communications, 2021-07-16)Bioproduction of renewable chemicals is considered as an urgent solution for fossil energy crisis. However, despite tremendous efforts, it is still challenging to generate microbial strains that can produce target biochemical ... -
Residual nitrite in processed meat products in Costa Rica: Method validation, long-term survey and intake estimations
(Elsevier Ltd, 2021-05-12)Ingestion of high amounts of nitrite due processed meat consumption could produce negative effects in human health. Here, we investigate long-term residual sodium nitrite content in processed meat products in Costa Rica ... -
Revisiting the fundamentals of p-nitrophenol analysis for its application in the quantification of lipases activity. A graphical update
(Universidad Nacional (Costa Rica), 2020-07-31)p-Nitrophenol (pNP) is a widely used compound for analytical determinations of several esterases (EC. 3.1.1.X), including lipases (E.C. 3.1.1.3). Most enzymatic measurements employ pNP derivatives such as ... -
Saneamiento de aguas residuales mediante humedales artificiales en el Museo de Cultura Popular de la Universidad Nacional
(Universidad Nacional (Costa Rica), 2013-06)El cumplimiento de los Objetivos de Desarrollo del Milenio en términos de acceso sostenible al saneamiento requiere incrementar el desarrollo de programas de investigación que promuevan opciones tecnológicas simples y de ... -
Scattering of light by colloidal aluminosilicate particles Produces the unusual sky-blue color of Río Celeste (Tenorio Volcano Complex, Costa Rica)
(2013-09-18)Río Celeste (Sky-Blue River) in Tenorio National Park (Costa Rica), a river that derives from the confluence and mixing of two colorless streams-Río Buenavista (Buenavista River) and Quebrada Agria (Sour Creek)-is renowned ... -
Self-assembly study of type I collagen extracted from male Wistar Hannover rat tail tendons
(BioMed Central Ltd, 2020-11-23)Background: Collagen, the most abundant protein in the animal kingdom, represents a promising biomaterial for regenerative medicine applications due to its structural diversity and self-assembling complexity. Despite ... -
Síntesis de precursores tipo 1,8-naftilimida: propiedades y usos potenciales para la detección selectiva de metales en agua
(Universidad Nacional (Costa Rica), 2019)El objetivo del presente trabajo fue sintetizar moléculas (cromóforos) que tuviesen la capacidad de combinarse con sustancias macrocíclicas para preparar macromoléculas (quimiosensores) que pudiesen utilizarse para la ... -
Síntesis, propiedades y aplicaciones de puntos cuánticos a base de carbono
(Revistes Catalanes amb Accés Obert, 2022)Los puntos cuánticos a base de carbono muestran propiedades ópticas y electrónicas de interés tecno-lógico debido a su confinamiento cuántico y el efecto de los grupos funcionales en sus bordes. Pueden ... -
Spatial and Temporal Variation of Stable Isotopes in Precipitation across Costa Rica: An Analysis of Historic GNIP Records
(2013-11-27)The location of Costa Rica on the Central American Isthmus creates unique microclimate systems that receive moisture inputs directly from the Caribbean Sea and the Pacific Ocean. In Costa Rica, stable isotope monitoring ... -
Stable isotopes reveal groundwater to river connectivity in a mesoscale subtropical watershed
(Taylor and Francis Ltd., 2021)The Corumbataí River basin (São Paulo, Brazil) has a critical situation regarding water availability due to the intensive use to support agriculture and urbanization, requiring scientific information to face water demand. ... -
Stable isotopic characterizacion of nitrate wet deposition in the tropical urban atmosphere of Costa Rica
(Springer, 2021-07-13)Increasing energy consumption and food production worldwide results in anthropogenic emissions of reactive nitrogen into the atmosphere. To date, however, little information is available on tropical urban environments where ... -
Student Camps to Promote Scientific Vocations in STEM: The Quimi Camp Case
(Universidad Nacional (Costa Rica), 2023-06-01)[Objetivo] Desde el año 1988 y hasta el año 2018, el estudiantado de secundaria en Costa Rica debía aprobar un examen final para graduarse de la escuela secundaria, y ser elegible para una educación universitaria pública. ...