Extent and toxicity of contaminated marine sediments in Southeastern Florida

Thirty sites were sampled in southern Biscayne Bay and Manatee Bay in December 1999 to determine the extent of toxicity in sediments. Analyses and assays included: pesticides and phenols in seawater; chemical contaminants in sediment; amphipod mortality, HRGS P450, sea urchin sperm fertilization and embryology, MicrotoxTM, MutatoxTM, grass shrimp AChE and juvenile clam mortality assays; sea urchin sperm, amphipod and oyster DNA damage; and benthic community assessment. Sediment sites near the mouth of canals showed evidence of contamination. Contaminant plumes and associated toxicity do not appear to extend seaward of the mouth of the canals in an appreciable manner. Concentrations of contaminants in the sediments in open areas of Biscayne and Manatee Bays are generally low. (PDF contains 140 pages

Contaminant trends in US National Estuarine Research Reserves

Inputs of toxic chemicals provide one of the major types of anthropogenic stress threatening our Nation's coastal and estuarine waters. To assess this threat, the National Oceanic and Atmospheric Administration's (NOAA’s) National Status and Trends (NS&T) Program Mussel Watch Project monitors the concentrations of more than 70 toxic chemicals in sediments and on the whole soft-parts of mussels and oysters at over 300 sites around the U.S. Twenty of the 25 designated areas that comprise NOAA's National Estuarine Research Reserve System (NERRS) have one or more Mussel Watch monitoring sites. Trace elements and organic contaminants were quantified including As, Ag, Cd, Cu, Hg, Ni, Pb, Zn, ΣPCBs, ΣPAHs, DDT and its metabolites, and butyltins. The Mussel Watch sites located in or near the 20 Reserves provide for both status and trends. Generally the Reserves have trace element and organic contaminant concentrations that are at or below the median concentration determined for all NS&T Mussel Watch monitoring data. Trends were derived using the Spearman-rank correlation coefficient. It was possible to determine if trends exist for sites at which six or more years of data are available. Generally no trends were found for trace elements but when trends were found they were usually decreasing. The same general conclusion holds for organic contaminants but more decreasing trends were found than for trace elements. The greatest number of decreasing trends were found for tributyltin and its metabolites. (PDF contains 203 pages

Spatial distribution of Chlorpyrifos and Endosulfan in USA coastal waters and the Great Lakes

Between 1994 and 1997, 258 tissue and 178 sediment samples were analyzed for chlorpyrifos throughout the coastal United States and the Great Lakes. Subsequently, 95 of the 1997 tissue samples were reanalyzed for endosulfan. Tissue chlorpyrifos concentrations, which exceeded the 90th percentile, were found in coastal regions known to have high agricultural use rates but also strongly correlated with sites near high population. The highest concentrations of endosulfans in contrast, were generally limited to agricultural regions of the country. Detections of chlorpyrifos at several Alaskan sites suggest an atmospheric transport mechanism. Many Great Lakes sites had chlorpyrifos tissue concentrations above the 90th percentile which decreased with increasing distance from the Corn Belt region (Iowa, Indiana, Illinois, and Wisconsin) where most agriculturally applied chlorpyrifos is used. Correlation analysis suggests that fluvial discharge is the primary transport pathway on the Atlantic and Gulf of Mexico coasts for chlorpyrifos but not necessarily for endosulfans. (PDF contains 28 pages

El Sector Solar Fotovoltaico en el Caribe Colombiano: Análisis Técnico y de Mercado

El presente artículo es producto de la tesis de maestría plan de marketing de sistemas solares fotovoltaicos para electrificación urbana, y describe la situación actual de la demanda y oferta de energía solar fotovoltaica (ESF) en la región caribe colombiana, zona que reúne las mejores condiciones para el crecimiento de esta industria, utilizando las metodologías de revisión bibliográfica y técnica analítica. Se adiciona también, cual es el rendimiento eléctrico de los módulos solares fotovoltaicos más ofertados en la región, mediante el uso de los modelos matemáticos para cálculo de sistemas fotovoltaicos

Renal vasculitis in Colombia

A retrospective review of publications about primary vasculitis cases was performed from the Colombian medical literature, the clinical and pathological features are described.The Renal vasculitis occurred in 33.9% of cases of primary vasculitis reviewed and was more frequent in women. The main clinical, hematological, immunological variables and nephropathology and immunosuppressive treatments used findings are described

Angeitis necrotizante sistémica no supurativa

1. Se estudian 3 casos de angeítis necrotizante sistémica no supurativa: un hombre de 36 y una mujer de 58 años con granulomatosis de Wegener y un hombre de 30 años con granulomatosis alérgica del tipo descrito por Churg y Strauss. 2. Se prefiere el hombre de angeítis necrotizante sistémica no supurativa como lo ha hecho Paronetto cuando trata este capítulo desde el punto de vista inmunopatológico. 3. Consideran los autores que la lesión renal es la periglomerulitis granulomatosa parahiliar y que su presencia ya en la biopsia tiene gran valor diagnóstico. 4. Se subraya que el cuadro clínico, la marcada eosinofilia tisular y la presencia de imágenes micromultinodulares en el ganglio linfático, apoyan sólidamente un diagnóstico de granulomatosis alérgica de la forma descrita por Churg y Strauss. 5. Se hace una amplia revisión bibliográfica

Responsabilidad Social Empresarial (RSE) en las plantas de beneficio de palma de aceite: Caso: departamento de Bolívar

This article analyzes corporate social responsibility (CSR) in palm oil mills in order to establish economically viable, environmentally compatible and socially acceptable criteria in the different palm oil and palm kernel extraction processes in order to seek excellence of the company with all its interest groups. The investigation was of analytical-descriptive type, with a mixed approach; He used documentary analysis as an instrument, under the framework of the theory of Corporate Social Responsibility. After the theoretical analysis of the dimensions of social responsibility, the productive and administrative processes of the benefit plants are reviewed and finally contributions are made in terms of their business performance, in terms of their economic, social and environmental performance.Este artículo analizó la responsabilidad social empresarial (RSE) en las plantas de beneficio de palma de aceite con el fin de establecer criterios económicamente viables, ambientalmente compatibles y socialmente aceptables en los distintos procesos de extracción de aceite de palma y palmiste, para buscar la excelencia de la empresa con todos sus grupos de interés. La investigación fue de tipo analítico-descriptivo, con enfoque mixto; utilizó como instrumento el análisis documental, bajo el marco de la teoría de la Responsabilidad Social Empresarial. Luego del análisis teórico de las dimensiones de la responsabilidad social, se revisan los procesos productivos y administrativos de las plantas de beneficio y finalmente se realizan aportaciones en términos de su actuación empresarial, en cuanto a su desempeño económico, social y ambiental

Marketing strategies for the internationalization of commercial SMES of Riohacha

La investigación tuvo como objetivo analizar las estrategias de marketing para la internacionalización de PYMES comercializables de Riohacha, utilizando el paradigma cuantitativo, con investigación de tipo descriptiva, diseño no experimental, transversal de campo. La población fueron las PYMES comerciales de Riohacha, conformada por 119 empresas comerciales de bienes y servicios. Los resultados indican que las PYMES están aplicando estrategias con las cuales puedan posicionarse en el mercado local y llegar al internacional. Concluyendo que las estrategias de marketing utilizadas por las empresas contribuyen a potencializar sus productos o servicios, impulsándolas al crecimiento y a tener ventajas competitivas.The research aimed to analyze marketing strategies for the internationalization of commercial SMEs in Riohacha, using the quantitative paradigm, with descriptive research, non-experimental design, and cross-sectional field. The population was the commercial SMEs of Riohacha, conformed by 119 commercial companies of goods and services. The results indicate that SMEs are applying strategies with which they can position themselves in the local market and reach the international market. Concluding that the marketing strategies used by companies, contribute to potentiate their products or services, driving them to growth and to have competitive advantages

Contrasts between utility maximisation and regret minimisation in the presence of opt out alternatives

An increasing number of studies of choice behaviour are looking at Random Regret Minimisation (RRM) as an alternative to the well established Random Utility Maximisation (RUM) framework. Empirical evidence tends to show small differences in performance between the two approaches, with the implied preference between the models being dataset specific. In the present paper, we discuss how in the context of choice tasks involving an opt out alternative, the differences are potentially more clear cut. Specifically, we hypothesise that when opt out alternatives are framed as a rejection of all the available alternatives, this is likely to have a detrimental impact on the performance of RRM, while the performance of RUM suffers more than RRM when the opt out is framed as a respondent being indifferent between the alternatives on offer. We provide empirical support for these hypotheses through two case studies, using the two different types of opt out alternatives. Our findings suggest that analysts need to carefully evaluate their choice of model structure in the presence of opt out alternatives, while any a priori preference for a given model structure should be taken into account in survey framing