Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

Se determinó la composición química del agua de lluvia y de niebla en tres sitios en la Reserva Biológica Monteverde, Puntarenas; entre octubre 2009 y enero 2010. Debido a su estado de conservación y a su ubicación geográfica sobre la deriva continental, la Reserva Biológica Monteverde ofrece un sitio de estudio ideal, para el estudio de la composición de las aguas atmosféricas (agua de lluvia y de niebla). Las muestras de agua de niebla se recolectaron al utilizar muestreadores de niebla con líneas de teflón, mientras que las de agua de lluvia se recogieron al emplear muestreadores de lluvia simples y uno de cascada. En ambos tipos de agua se analizaron las especies iónicas más relevantes: H3O+, NH4 +, Ca2+, Mg2+, K+, Na+, Cl-, NO3 - y SO4 2-, al utilizar cromatografía de iones y detección por conductividad eléctrica. Las concentraciones promedio de estas especies en el agua de lluvia estuvieron entre 0,54 ± 0,02 μeq L-1 y 101± 3 μeq L-1, mientras que en el agua de niebla variaron entre 1,00 ± 0,02 μeq L-1 y 93 ± 4 μeq L-1. Además, se presentan el balance iónico y los factores de enriquecimiento con respecto al mar y el suelo de ambos tipos de muestras.

This article describes the purpose and activities of the project Promoting Mathematics Education in Rural Areas of Costa Rica. The activity has focused on two objectives. First, supporting and monitoring students who have expressed interest in studying a mathematics teacher. To achieve this, it has been working with students who have an ideal profile for the career, mainly from rural areas. The second objective is to conduct training workshops for high school in-service teachers, to strengthen and improve their knowledge in the area of mathematics. Among the results of the project, it can be highlighted a significant increase in the enrollment of students in the career of Mathematics Education in 2010 and 2011, and the training processes in the field of Real Functions of Real Variable and Geometry at different regional areas mostly rural as Aguirre, Sarapiquí, Coto, Buenos Aires, Limón, Cañas, Pérez Zeledón, Nicoya, Los Santos, Turrialba, Puriscal, Desamparados, San Carlos, Puntarenas, Limón, Liberia, Santa Cruz y Upala.

Los desechos lignocelulósicos de la producción de piña son una materia prima muy útil para la producción de xilosa por medio de hidrólisis, que a su vez, puede convertirse a xilitol. El objetivo de este trabajo fue estudiar la hidrólisis de la cáscara de piña con concentración de ácido sulfúrico y tiempo de reacción variable  (2-6% y 0-350 min respectivamente) y temperatura de 98˚C. Se determinó la concentración de xilosa, glucosa y los productos de degradación como ácido acético y furfural. Las condiciones óptimas encontradas para la hidrólisis fueron 6% H2SO4 a 98 ˚C por 83 min con un rendimiento de 26,9 g xilosa/L, 2,61 g glucosa/L, 7,71 g ácido ácetico/L y 0,29 g furfural/L.

Sediments of Tamarindo estuary and its tributaries were evaluated in order to determine the effect of anthropogenic activities of the surrounding communities. The evaluation relied on texture, total phosphorus, organic matter, and heavy metal (Pb, Cu, Ni and Cr) analyses. The study spanned four sampling campaigns between October 2007 and April 2008, including four climatic seasons: rainy season, rainy-dry transition, dry season and dryrainy transition. Five sampling points were selected at Tamarindo estuary and three additional sites were set at Matapalo, Lomas and Lajas rivers. Ontario Ministry of the Environment regulation was used to evaluate sediment quality. It was determined that theanthropogenic activities of the surrounding communities exert a negative impact over the sediment quality; the pollution effect caused by such activities was rated as lower effect.

This article shows a general way to implement recursive functions calculation by linear tail recursion. It emphasizes the use of tail recursion to perform computations efficiently.

This paper offers a description of the methods, techniques and resources of teaching used by a sample of teachers from I and II Cycle of Basic General Education in the Dirección Regional Educativa de Heredia to teach Probability and Statistics. Regarding the methods, the most relevant results are the following: it was found a preference for traditional teaching strategies (methods most frequently used: deductive, expository, study of text, and collective). On the other hand, the teaching techniques identified with frequent use were brainstorming, entertainment´s activities, and work in groups, which are good tools to promote process of teaching and learning in which students interact with problem situations but also be used in traditional lessons. The technique called preparation of projects was rarely used. Moreover, among the main teaching resources chosen by teachers to teach Probability and Statistics are blackboards and photocopied materials, also mentioned the entertainment´s activities and concrete materials.

This article describes the design and implementation of computer-aided tool called Relational Algebra Translator (RAT) in data base courses, for the teaching of relational algebra. There was a problem when introducing the relational algebra topic in the course EIF 211 Design and Implementation of Databases, which belongs to the career of Engineering in Information Systems of the National University of Costa Rica, because students attending this course were lacking profound mathematical knowledge, which led to a learning problem, being this an important subject to understand what the data bases search and request do RAT comes along to enhance the teaching-learning process.It introduces the architectural and design principles required for its implementation, such as: the language symbol table, the gramatical rules and the basic algorithms that RAT uses to translate from relational algebra to SQL language. This tool has been used for one periods and has demonstrated to be effective in the learning-teaching process.  This urged investigators to publish it in the web site: www.slinfo.una.ac.cr in order for this tool to be used in other university courses.

This paper presents the conceptualization and use of a virtual classroom in the course EIF-200 Fundamentos de Informática, first course in the Information Systems Engineering career of the Universidad Nacional of Costa Rica. The virtual classroom is seen as a complement to the class and is conceived as a space that allows to centralize teaching resources, thereby promoting the  democratization of knowledge among students and teachers. Furthermore, this concept of virtual classroom helps to reduce the culture of individualism, present many times in university teaching practices, and contributes to create new opportunities to learn from other colleagues within a culture of reflection, analysis and respectful dialogue aimed to improve the teaching practices.

En base a la comparación de los Códigos Procesal Civil español y peruano, y partiendo de la concepción constitucional de la garantía procesal de la prueba, el autor deja de lado la concepción del derecho de la prueba, como un subsistema procesal de aplicación acrítica e intertemporal de normas procesales. Por el contrario, afirma que el derecho de la prueba se construye en torno a un sistema de garantías procesales que actúan con autonomía y sustantividad propias como derecho de la Garantía Probatoria. Todo ello, con la finalidad de alcanzar el derecho a un proceso justo. En ese sentido, para lograr su objetivo nos comenta y describe temas relacionados a la institución de la “carga de la prueba”, por ejemplo: “la prueba diabólica”, “la causa petendi”, “la modificación”, “exoneración” e “inversión” de la carga de la prueba. Based on a comparison of the Spanish and Peruvian codes of Civil Procedure and proceeding from the constitutional conception of procedural guarantees of standards of proof, the author eschews the conception of Law of Proof as a procedural subsystem of the accritical and intertemporal application of procedural norms. On the contrary, Lorca Navarrete affirms that the Law of Proof is constructed on the basis of a system of procedural guarantees that function with their own autonomy and substantivity such as the Law of Evidentiary Guarantee. The goal here is to achieve the right to a fair process. In order to explain his argument, the author discusses and describes questions related to the concept of “burden of proof,” for example, “the diabolic proof,” “the causa petendi,” “the modification,” “exoneration” and “investment” of the burden of proof.

En razón al surgimiento de necesidades procesales distintas, y dejando de lado el modelo clásico conforme al cual toda decisión jurisdiccional consagra una parte vencedora y otra vencida, es decir, resoluciones estimatorias y desestimatorias; han surgido nuevos tipos de resoluciones con distintas finalidades que no se enmarcaban dentro del modelo clásico. Esto revela, una vez más que el Derecho Procesal Civil ha dejado de ser el mecanismo tosco y carente de refinamiento. En el presente artículo el autor, realiza una enumeración y descripción de esta tipología diferente de resoluciones judiciales: anticipatorias, determinativas, docentes, exhortativas e inhibitorias. As a result of the development of different procedural necessities and leaving behind the classic model according to which all court rulings establish a winning party and a losing party (that is, rulings are either positive or negative), new types of rulings have been developed with different goals that do not fit within the classic model. This reveals, once again, that Civil Procedure Law has stopped being a mechanism that is crude and lacking in refinement. In this article, Peyrano enumerates and describes this distinct typology of court decisions: anticipatory, determinative, didactic, admonishing and inhibitory.