Browsing Facultad de Ciencias Exactas y Naturales by Title
Now showing items 279-298 of 2529
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El bachillerato de matemática del 2003 un debate relevante
(Universidad Nacional (Costa Rica), 2003)El objetivo de este artículo es analizar el criterio de algunos intelectuales acerca de la prueba de Bachillerato de matemática, sobre todo la prueba del año 2003: las causas de los malos resultados y posibles soluciones. ... -
Bacterial multi-resistance to antibiotics in water from plant cavities (phytotelms) in a deep tropical forest from Costa Rica
(Universidad Estatal a Distancia (UNED) (Costa Rica), 2023)Introduction: The spread of antimicrobial resistance in natural environments continues to be reported throughout the world; nevertheless, there is no study about phytotelms (water in the natural cavities of plants) in the ... -
Bacterias luminiscentes: Alternativa para la evaluación de la contaminación marino costera en Costa Rica
(Colegio de Biólogos (Costa Rica), 2014-07-12)Se lograron aislar bacterias luminiscentes del Golfo de Nicoya, Costa Rica. Se discuten las aplicaciones actuales de estos microorganismos como bioindicadores de contaminación ambiental y su potencial como alternativa ... -
Base de datos geodésicos
(Universidad Nacional (Costa Rica), 1989)Este trabajo consistió en hacer una base de datos eficiente y amigable que facilite a los profesionales de la topografía, la geodesia y otros profesionales afines, la obtención de información geodésica en forma inmediata, ... -
Base de datos sobre la calidad del agua superficial en río Bermúdez
(Universidad Nacional (Costa Rica), 2021-06-21) -
Baseflow recession analysis in the inland Pacific Northwest of the United States
(Springer Nature, 2015)The storage-discharge relationships of 26 water sheds in the inland Pacific Northwest of the United States were analyzed. Four fitting methods were used to obtain the baseflow coefficients: lower envelope, organic corre ... -
Batalla jabonosa
(2020-10)Este cuento narra la historia de la general Derma y sus soldados, células que viven en el pequeño cuerpo de Harry, que día a día luchan por protegerlo. Este es un cuento fue escrito para niños o para todo aquel que quiera ... -
Batch fertility and larval parameters of the jaguar cichlid (Cichlasoma managuense) spawned in the laboratory
(Universidad Nacional (Costa Rica), 1994-05-06)Abstract: Batch fertility and larval parameters of 32 spawns of the jaguar guapote (Cichlasoma managuense) in the laboratory were analyzed. Batch fertility was positively correlated with the female weight with spawns between ... -
Bayesian estimates of the mean recharge elevations of water sources in the Central America region using stable water
(Elsevier, 2020)Study region: Central America. Study focus: Knowledge of the mean recharge elevation (MRE) of water resources is important where water resources are vulnerable. The purpose of this study was to develop and apply a Bayesian ... -
Behavioral plasticity mitigates risk across environments and predators during anuran metamorphosis
(Behavioral Ecology, 2013)Most animals metamorphose, changing morphology, physiology, behavior and ecological interactions. Size- and habitat-dependent mortality risk is thought to affect the evolution and plastic expression of metamorphic timing, ... -
Beta diversity and oligarchic dominance in the tropical forests of Southern Costa Rica
(Blackwell Publishing Ltd, 2019-03)Recent studies have reported a consistent pattern of strong dominance of a small subset of tree species in neotropical forests. These species have been called “hyperdominant” at large geographical scales and “oligarchs” ... -
Bioalfabetización en el desarrollo del currículum de Matemática, Español y Estudios Sociales [recurso electrónico]
(Universidad Nacional (Costa Rica), 2010)La presente investigación tiene como objetivo diagnosticar y generar una propuesta para poder incluir un proceso bioalfabetizador en los currículos de Matemática, Español y Estudios Sociales en el | trimestre de sétimo ... -
Biocomposite Films of Polylactic Acid Reinforced with Microcrystalline Cellulose from Pineapple Leaf Fibers
(Tech Science Press, 2019)Poly(lactic acid) (PLA) composite films reinforced with microcrystalline cellulose (MCC) extracted from pineapple leaf fibers (PALF) were prepared by a solution casting procedure. In an attempt to improve the interaction ... -
Biocomposites of Low-Density Polyethylene PlusWood Flour or Flax Straw: Biodegradation Kinetics across Three Environments
(MDPI journals, 2021-06-29)The purpose of this study was to assess the potential for biocomposite films to biodegrade in diverse climatic environments. Biocomposite films based on polyethylene and 30 wt.% of two lignocellulosic fillers (wood flour ... -
Biodegradable polyurethanes from sugar cane biowastes
(Cellulose chemistry and technology, 2011)In a previous work, it was demonstrated that 70% of the molasses isolated from the biowaste generated by the agro-industrialization of sugar cane allow obtaining composite materials with adequate mechanical properties ... -
Biodeterioration and biodegradation of Roman monuments: A comparison of the current status of 18th century paintings by the Canalettos
(2014)Worldwide there is an urgent need to monitor the conditions of monuments affected by biodeterioration and biodegradation, but no long term data exist for most of them. Here is an exception in the case of certain Roman ... -
Biofabrication of Gold Nanotriangles Using Liposomes as a Dual Functional Reductant and Stabilizer
(American Chemical Society, 2021-03-23)Negatively charged liposomes accomplished both functions as a reducing and stabilizing agent in the synthesis of gold nanotriangles (GNTs). Liposomes are based on a mixture of phospholipids phosphatidylcholine/phosphoglycerol, ... -
Biofertilización orgánica de almácigos de café (Coffea arabica L.) con compost producido a partir de residuos biomásicos locales, microorganismos de montaña y lodos digeridos de biodigestor en la región de Monteverde, Costa Rica
(Doctorado en Ciencias Naturales para el Desarrollo (DOCINADE), 2019)El presente trabajo aporta evidencia empírica sobre el rendimiento y calidad de un nuevo sistema de fertilización para la producción de almácigo de café orgánico que utiliza compost elaborado con residuos biomásicos locales, ... -
Biogardens as constructed wetlands in tropical climate: A case study in the Central Pacific Coast of Costa Rica
(Elsevier, 2019-03-25)In Costa Rica, <10% of wastewater is treated before its discharge. This generates a significant impact on the environment, public health, and tourism industry, which is one of the country's main economic activities. ... -
Biogenic silica-based microparticles obtained as a sub-product of the nanocellulose extraction process from pineapple peels
(Nature Publishing Group, 2018-07-10)Silica in plant tissues has been suggested as a component for enhancing mechanical properties, and as a physical barrier. Pineapples present in their shell and bracts rosette-like microparticles that could be associated ...