Browsing Facultad de Ciencias Exactas y Naturales by Title
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Key drivers controlling stable isotope variations in daily precipitation of Costa Rica: Caribbean Sea versus Eastern Pacific Ocean moisture sources
(Elsevier, 2016)Costa Rica is located on the Central American Isthmus, which receives moisture inputs directly from the Caribbean Sea and the Eastern Pacific Ocean. This location includes unique mountainous and lowland microclimates, but ... -
Key hydrological processes in the Del Azul Creek basin, sub-humid Pampean Plain
(Elsevier B.V., 2021-02)Groundwater plays an important role in the economic development of the Chaco-Pampean Plain (Argentina), where industry, agriculture and cattle farming are the main economic activities. The 66% of the country's population ... -
Kinetics of anaerobic degradation of screened dairy manure by upflow fixed bed digesters: Effect of natural zeolite addition
(Taylor & Francis, 2009)The effect of the hydraulic retention time (HRT) on the performance of two up-flow anaerobic fixed bed digesters (UFAFBDs) packed with waste tire rubber (D1) and waste tire rubber and zeolite (D2) as micro-organism ... -
Kinetics of Isothermal Degradation Studies in Adhesives by Thermogra vimetric Data: Effect of Hydrophilic Nanosilica Fillers on the Thermal Properties of Thermoplastic Polyurethane-Silica Nanocomposites
(Recent Patents on Nanotechnology, 2008)The kinetics of thermal degradation process on thermoplastic polyurethanes (TPUs) adhesives with hydrophilic nanosilicas was studied using isothermal thermogravimetric analysis within the temperature range from 360 °C ... -
Knowledge Evidenced by Prospective Mathematics Teachers when Performing a Task Involving Geometry, Teaching and the Use of Technology
(Lutheran University of Brazil, 2019)The types of knowledge that prospective mathematics teachers use when faced with tasks involving technology are interesting because this knowledge can be used as a basis for analyzing the relevance of these types of ... -
Knowledge of mathematics teachers in initial training regarding mathematical proofs: Logic-mathematical aspects in the evaluation of arguments
(Universidad Nacional, Costa Rica, 2022-01-31)The objective of this study is to characterize the knowledge of mathematics teachers in initial training (MTITs) at the Universidad Nacional (Costa Rica) on the logic-syntactic and mathematical aspects ... -
La noción de idoneidad didáctica como herramienta para la reflexión de la clase de matemática
Poder realizar una reflexión de lo que ocurre en la clase de matemática es una competencia que debe poseer el profesor en servicio. Esta actividad de reflexión es compleja y más si no se cuenta con una estructura que permita ... -
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. ... -
LANGUAGE AND A PHYSICAL ORGANIZATION TECHNIQUE FOR SUMMARY TABLES.
(Proceedings of ACM-SIGMOD 1985 International Conference on Management of Data, 2004)A summary table is a tabular representation of summary data, and is a useful data structure for statistical databases. Primitive summary tables are basic building blocks of summary tables, and can be represented as relations ... -
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 ... -
Lead acid battery recycling in Costa Rica: A case study
(WIT Transactions on Ecology and the Environment, 2012)This work describes the production of secondary lead in a smelter located in Costa Rica. The only input of the plant is scrap automotive batteries. We describe the environmental management strategies used for waste ... -
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 ... -
Learning by making: A framework to revisit practices in a constructionist learning environment
(Blackwell Publishing Ltd, 2021)Makerspaces are collaborative workspaces where people construct their ideas using a variety of ma terials and tools ranging from no tech to high tech, where components can be moulded and transformed into different ... -
Lepidochelys olivacea status and its relationship with nest management on the eastern coast in the Pacifico of Guatemala
(Universidad Nacional (Costa Rica), 2021)Marine turtles are reptiles that have lived in the Earth’s oceans and nested on the beaches starting several million years ago and also have coexisted with coastal communities since humans colonized beach areas across the ... -
Levantamiento topográfico y catastral de la zona marítimo terrestre
(Universidad Nacional (Costa Rica), 1992)El objetivo de este trabajo es aportar una metodología general que brinde una base apropiada a las instituciones encargadas de la administración de la zona marítimo terrestre que permita facilitar y regular los procesos ... -
Liberación de juveniles de pargo manchado Lutjanus guttatus (Steindachner, 1869), como estrategia para la conservación de la especie y educación ambiental marino costera
(Universidad Nacional de Colombia, 2019)La percepción ambiental como herramienta de educación y sensibilización a la conservación de los recursos marinos, fue implementada en la liberación de 102.000 juveniles de Lutjanus guttatus con la participación activa ... -
Lichen community structure and richness in three mid-elevation secondary forests in Costa Rica
(Universidad de Costa Rica (Costa Rica), 2021-06-21)Introduction: Lichen diversity, community structure, composition and species abundance have been used as indicators of the integrity and ecological continuity of tropical forest ecosystems. Objectives: To assess ... -
Life zone and habitat disturbance do not explain the coexistence in Sturnira bat species
(Springer (Alemania), 2022-06-23)One of the key questions in ecology is to understand the mechanisms that modulate the coexistence between syntopic species. Climate and habitat perturbation gradients have been proposed as moderators of species coexistence. ...