Transverse Structure of Wind-Driven Flow at the Entrance to an Estuary: Nansemond River

Observations of current velocity profiles were combined with an analytical solution to study the transverse partition of the wind-driven flow in an estuary, the Nansemond River, which is a tributary of the James River in the Chesapeake Bay. Observations spanned two periods of nearly 3 months in autumn-winter of 2003-2004 and spring-summer 2004. The wind-driven circulation consisted of downwind flow over the shoal and upwind flow in the channel at the entrance to the estuary. This pattern developed mainly with landward winds and provided observational evidence that sustains analytical and numerical model results. The transverse structure of the flow showed synoptic temporal variability (3-7 days), which corresponded to the variability of winds and sea level. Synoptic variability seemed to be more influential in autumn-winter than in spring-summer. However, variability of 1-2 days was persistent in both periods of observation. Also, the transverse structure of the wind-driven flows was linked to a counterclockwise recirculation pattern previously observed with survey data. Part of the flow going into the tributary over the shoal might recirculate and form or enhance the outflow in the channel. As suggested by the temporal scale of the wind, the recirculation might weaken or even reverse direction every 3-7 days at the entrance to the estuary. Further detailed studies are needed to better define the extent of this recirculation

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Determinación de la aptitud de suelo para el cultivo de café (coffea arábica), en el municipio de Neiva – Huila, con el uso de los sistemas de información geográfica SIG

En el municipio de Neiva Huila la caficultura tiene una proyección de incremento de nuevas plantaciones en café, así como también el aprovechamiento completo de los recursos suelo y agua, por tal razón se hace necesario Diseñar y construir un modelo lógico que exponga la problemática y las posibles soluciones; mediante la identificación de posibilidades áreas de siembra que no estén en zonas de protección ambiental y de restricciones técnicas para la producción agropecuaria estableciendo delimitaciones en las zonas de estudio, quedando plasmadas en este documento de investigación. En ese sentido el municipio de Neiva por la ubicación geográfica y geoespacial cuenta con gran parte de las aptitudes en los ámbitos ambientales y edafológico permitiendo que el productor desconozca las restricciones técnicas y ambientales que se rigen en el territorio nacional, por ende con la elaboración de esta investigación haciendo uso de las herramientas técnicas y tecnológicas como QGIS, podrá servir como instrumento para la identificación y zonificación de zonas que se pueden implementar cultivos sin que se infrinjan las normas ambientales.In the municipality of Neiva Huila, coffee farming has a projection of increasing new coffee plantations, as well as the complete use of soil and water resources, for this reason it is necessary to design and build a logical model that exposes the problems and the possible solutions; by identifying possible planting areas that are not in environmental protection zones and technical restrictions for agricultural production, establishing delimitations in the study areas, which are reflected in this research document. In this sense, the municipality of Neiva, due to its geographical and geospatial location, has a large part of the aptitudes in the environmental and soil fields, allowing the producer to be unaware of the technical and environmental restrictions that are governed in the national territory, therefore with the preparation of This research, making use of technical and technological tools such as QGIS, may serve as an instrument for the identification and zoning of areas where crops can be implemented without violating environmental regulations

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Caldas como territorio ha presentado una serie de transformaciones, propias de una región en construcción. Marcada históricamente por la huella que dejaron los colonizadores antioqueños en el siglo XIX, se insertó a la economía mundial gracias al cultivo del café. En su historia de construcción de identidad, las luchas sociales se desataron por el acceso a la tierra, más aún cuando los empresarios de la colonización utilizaron los colonos para valorizar sus tierras, para luego intentar vendérselas a precios de usura. En el siglo XX, exceptuando la denominada época de la violencia, los caficultores de Caldas no registran acciones sociales que demuestren confrontación hacia el Estado, el statu quo, o la Federación Nacional de Cafeteros, institución que por su poder político y económico, reemplazaba en gran medida al Estado; sólo hasta la década del ochenta vuelve a surgir el interés organizarse, esta vez para enfrentar la grave crisis económica a que los ha conducido la caída vertiginosa de los precios del grano, con hondas repercusiones sociales.In the last two decades, the emergence of social protests in the coffee-producing zone have awaken various questionings in the understanding of a region, that has been seen, excluding the bipartisan violent period, as being economically well - off due to the wealth derived from the coffee production, and socially harmonious as an effect of the social organization installed by the Federación Nacional de Cafeteros (National Federation Of Coffee-Growers). This image of harmony and prosperity has become weak due to the crisis which the coffee industry is experiencing at the moment and to the incapability of the government and the Federation to solve this crisis. Therefore, the emergence of social movements and organizational figures, different from that of the Federation, is an approach that the coffee-growers have taken to counterattack the threat of losing the way of life that has been passed on from generation to generation

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Caldas como territorio ha presentado una serie de transformaciones, propias de una región en construcción. Marcada históricamente por la huella que dejaron los colonizadores antioqueños en el siglo XIX, se insertó a la economía mundial gracias al cultivo del café. En su historia de construcción de identidad, las luchas sociales se desataron por el acceso a la tierra, más aún cuando los empresarios de la colonización utilizaron los colonos para valorizar sus tierras, para luego intentar vendérselas a precios de usura. En el siglo XX, exceptuando la denominada época de la violencia, los caficultores de Caldas no registran acciones sociales que demuestren confrontación hacia el Estado, el statu quo, o la Federación Nacional de Cafeteros, institución que por su poder político y económico, reemplazaba en gran medida al Estado; sólo hasta la década del ochenta vuelve a surgir el interés organizarse, esta vez para enfrentar la grave crisis económica a que los ha conducido la caída vertiginosa de los precios del grano, con hondas repercusiones sociales.In the last two decades, the emergence of social protests in the coffee-producing zone have awaken various questionings in the understanding of a region, that has been seen, excluding the bipartisan violent period, as being economically well - off due to the wealth derived from the coffee production, and socially harmonious as an effect of the social organization installed by the Federación Nacional de Cafeteros (National Federation Of Coffee-Growers). This image of harmony and prosperity has become weak due to the crisis which the coffee industry is experiencing at the moment and to the incapability of the government and the Federation to solve this crisis. Therefore, the emergence of social movements and organizational figures, different from that of the Federation, is an approach that the coffee-growers have taken to counterattack the threat of losing the way of life that has been passed on from generation to generation

Computational modeling of the mechanical modulation of the growth plate by sustained loading

This paper presents a computational model that describes the growth of the bone as a function of the proliferation and hypertrophy of chondrocytes in the growth plate. We have included the effects of the mechanical loads on the sizes of the proliferative and hypertrophic areas, the number of proliferative chondrocytes and the final size of the hypertrophic chondrocytes. The validation of the model was performed with experimental data published on other investigations about proximal tibia of rats, subjected to sustained axial stresses of 0.1 MPa, 0.0 MPa, -0.1 MPa and −0.2 MPa. Growth was simulated during 23 days, obtaining numerical errors between 2.77% and 3.73% with respect to experimental growth rates. The results obtained show that the model adequately simulates the behavior of the growth plate and the effect of mechanical loads over its cellular activity