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    ABSTRACT: A historic analysis of the classification of Scarabaeoidea is presented. The analysis comprises a historic comparison of the type and number of characters of the genera and their grouping into higher-level taxa. The analysis is divided into three time periods, including a review of 70 publications on scarab systematics (beginning with Linnaeus). The first period (1735–1858) encompasses an era prior to the publication of Darwin's The Origin of Species, and it is, therefore, a classification process arguably free of any evolutionary influences. The second period (1859–1949) includes a comparative synthesis on the classification of the Scarabaeoidea based on faunistic and taxonomic works. The third period (1950–2006) summarizes and analyzes classifications influenced by phylogenetic theories and is based on monographs, faunal studies, keys for regional fauna, papers on comparative morphology, and studies specifically devoted to the understanding of evolutionary relationships and processes in the Scarabaeoidea. A large problem concerning the classification and phylogeny still remains because most studies do not consider all the diversity of the Scarabaeoidea in a single analysis.
    The Coleopterists Bulletin 01/2009;
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    ABSTRACT: This study is a qualitative exploratory analysis of the communities of Turrialba, Siquirres and Guácimo, which border the Parismina River of Costa Rica. The main purpose of this study is to identify the structural weaknesses that are present in the enterprises and the impact of these weaknesses on the capacity for raising the sustainable development competitiveness for the area. The study used semi-structured interviews and focal interviews as instruments of data collection. In addition, the study used the community of Los Santos, located in the Central Valley of Costa Rica, as a reference for comparison. The results indicate weaknesses related to the capacity of organization, financial knowledge, and low technological innovation that demonstrates that the enterprises have a greater direction towards spurious competitiveness.
    Ecological Engineering. 01/2008;
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    ABSTRACT: Recibido 18 de abril 2006. Aceptado 15 de agosto 2006. RESUMEN La digestión anaeróbica o biodigestión es considerada una herramienta efectiva en el manejo de desechos orgánicos y la producción de metano (CH 4) como una fuente de energía renovable. Sin embargo, su diseminación ha sido limitada por los altos costos de instalación de plantas de biogás convencionales. Una planta de biogás o biodigestor de polietileno es una alternativa para la producción de biogás a bajo costo; una tecnología que ofrece beneficios directos y funcionales. Como beneficios directos se han identificado el reemplazo de la combustión de combustibles fósiles gracias a la producción de CH 4 y disminución en el uso de fertilizantes sintéticos por el contenido de nutrientes del material digerido. La estimación de valores funcionales incluye el potencial del uso de biogás para reducir la emisión de gases causantes del efecto invernadero (calentamiento global) emitidos durante la combustión de combustibles fósiles. Este estudio estima los beneficios directos y funcionales que pueden derivarse de la instalación de un biodigestor de 7,2 metros cúbicos de volumen. Palabras claves: Análisis de ecosistema, producción de biogás a bajo costo, valoración monetaria. ABSTRACT Anaerobic digestion or biodigestion is considered a very effective tool for the management of organic wastes and for the production of the renewable energy source, methane (CH 4). However, the use of biodigestion has been limited by the high cost of conventional apparatus for biogas production. The polyethylene biodigester is a low-cost alternative for biogas production; a technology that offers direct and practical benefits. The direct benefits of using this technology include CH 4 gas production which can be used to replace fossil fuel combustion as an energy source, and nutrients in the effluent which can be used to replace synthetic chemical fertilizers in crop production. The estimation of practical benefits include the potential use of CH 4 gas to reduce the emission of greenhouse gases, a cause of global warming, which are released during the combustion of fossil fuels. In this study these benefits were estimated with the installation of a 7.2 cubic meter biodigester.
    01/2006; 2:15-25.

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5o Seminario Manejo y Utilización de Pastos y Forrajes en Sistemas de Producción Animal 1999: Barinas. Rony Tejos (Editor). Universidad Nacional Experimental de los Llanos Occident...
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Biological Control. 01/2008;
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