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Search Results: 1 - 10 of 461786 matches for " A. Teller "
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Caracterización socio-educativa de una comunidad Warao: Estado Delta Amacuro
Tellería,Nelson;
Investigación y Postgrado , 2008,
Abstract: the main objectives of this descriptive and ethnographic field research are: to describe the present habitat of a warao community, determine the socio-economic and educational aspects of a sample population and to describe aspects such as: social organization, cosmovision, socio-cultural changes and perspectives for the future, in the framework of the bilingual intercultural education programme offered to the teachers of this ethnic group by the ipr ?el mácaro?. the warao?s are an indigenous community that lives in the orinoco delta. the 73 members of the group of students that are part of this programme were key informants. the data was triangulated by means of participating observation and in-depth interviews. the instruments used for data gathering were: video and photographic cameras, notebooks, gathering of samples of objects commonly used and self-response questionnaires. this project will contribute to the fulfillment of the mission of the university in this area of research as well as to improve the quality of intercultural education.
The effects of aerosols on precipitation and dimensions of subtropical clouds: a sensitivity study using a numerical cloud model
A. Teller ,Z. Levin
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2006,
Abstract: Numerical experiments were carried out using the Tel-Aviv University 2-D cloud model to investigate the effects of increased concentrations of Cloud Condensation Nuclei (CCN), giant CCN (GCCN) and Ice Nuclei (IN) on the development of precipitation and cloud structure in mixed-phase sub-tropical convective clouds. In order to differentiate between the contribution of the aerosols and the meteorology, all simulations were conducted with the same meteorological conditions. The results show that under the same meteorological conditions, polluted clouds (with high CCN concentrations) produce less precipitation than clean clouds (with low CCN concentrations), the initiation of precipitation is delayed and the lifetimes of the clouds are longer. GCCN enhance the total precipitation on the ground in polluted clouds but they have no noticeable effect on cleaner clouds. The increased rainfall due to GCCN is mainly a result of the increased graupel mass in the cloud, but it only partially offsets the decrease in rainfall due to pollution (increased CCN). The addition of more effective IN, such as mineral dust particles, reduces the total amount of precipitation on the ground. This reduction is more pronounced in clean clouds than in polluted ones. Polluted clouds reach higher altitudes and are wider than clean clouds and both produce wider clouds (anvils) when more IN are introduced. Since under the same vertical sounding the polluted clouds produce less rain, more water vapor is left aloft after the rain stops. In our simulations about 3.5 times more water evaporates after the rain stops from the polluted cloud as compared to the clean cloud. The implication is that much more water vapor is transported from lower levels to the mid troposphere under polluted conditions, something that should be considered in climate models. Final Revised Paper (PDF, 1879 KB) Discussion Paper (ACPD) Citation: Teller, A. and Levin, Z.: The effects of aerosols on precipitation and dimensions of subtropical clouds: a sensitivity study using a numerical cloud model, Atmos. Chem. Phys., 6, 67-80, doi:10.5194/acp-6-67-2006, 2006. Bibtex EndNote Reference Manager XML
Passerine bird communities of Iberian dehesas: a review
Tellería, J. L.
Animal Biodiversity and Conservation , 2001,
Abstract: The Iberian dehesas are a man-made habitat composed of scattered oaks (Quercus spp.) and extensive grass cover occupying three million ha in south-western Iberia. This paper compares the structure of the passerine bird communities in this region with other bird assemblages of Iberian woodlands. Although forest bird numbers in the southern half of the Iberian peninsula are decreasing, the dehesas show the highest richness in breeding birds, seemingly as the result of the increased presence of border and open-habitat birds. A low intra-habitat turnover of species was observed in the dehesas, with birds recorded at a sampling point accounting for a high percentage of the total richness of the community. This can be related to the low spatial patchiness of this habitat. In winter, the dehesas continued to maintain many bird species, but showed bird densities similar to other woodlands. This pattern, as well as the scarcity of some common forest passerines during the breeding period, could result from the removal of the shrub layer typical of Mediterranean woodlands.
La cestería indígena en la cultura artesanal Venezolana
Tellería,Nelson; Conde,Carmen;
Investigación y Postgrado , 2004,
Abstract: venezuelan popular handcrafts are heavily influenced by local aboriginal culture that can be seen in basketry, weaving and pottery. the cultural heritage is manifested in the production of popular artisans across the country. the objective of this particular research was to compile the various aborigine basketries commonly used in the different regions of the country. it is a descriptive research encompassing both documentation and field phases. the latter included a non structured, open interview to a sample of 55 artisans and 20 informants in 9 states. it also included expert opinions and bibliography on the taxonomy of the plants used to obtain the fibers. graphics and tables were done. results showed that popular basketry in venezuela has its roots in aboriginal basketry and it stands out for being utilitarian. one of the best known is the "catumare", a loading basket and another one, the "manare" that is use to prepare casabe. the techniques and raw material follow certain pattern with some variations that depends on the cultural group and region. we believe that here is a necessity to study ethno botanical to understand the plants that provide the fiber that are used in basketry and look for their preservation, also promoting popular handcrafts workshops to keep our cultural values for future generations.
Cooperación universitaria y conservación de la biodiversidad: perspectivas en Iberoamérica
J.L. Tellería
Ecosistemas , 2008,
Abstract: La cooperación universitaria al desarrollo está creciendo en Espa a por lo que la Conferencia de Rectores de Universidades de Espa a ha recomendado que se organice sobre la base de la continuidad de las actuaciones, la complementariedad de las iniciativas, la corresponsabilidad de las instituciones participantes y la naturaleza "no onerosa-no lucrativa" de los proyectos. Desde tales premisas, este artículo repasa el interés de la conservación de la biodiversidad como objeto específico de cooperación y comenta las posibilidades que brinda Iberoamérica en este campo. Esta región cuenta con una naturaleza espectacular que está siendo degradada rápidamente. Por fortuna alberga excelentes universidades e investigadores con los que es posible establecer planes conjuntos de educación e investigación dirigidos a la conservación en aquellas áreas más amenazadas. Dado que Iberoamérica es un escenario clave en la lucha mundial por la conservación de la biodiversidad, parece oportuno desarrollar proyectos inter-universitarios dirigidos a este objetivo
Una visión de género en el área de Recursos Naturales
Tellería Jorge, M. Teresa
Arbor : Ciencia, Pensamiento y Cultura , 2002,
Abstract: Not available Se me pide que escriba, dentro de este monográfico dedicado a una visión de género en el CSIC, acerca de la situación concreta en el área de Recursos Naturales. El encargo que se me hace es para mí doblemente complicado. Por un lado, he de escribir sobre algo de lo que únicamente tengo una vaga opinión personal, a buen seguro sesgada, fruto de mi particular experiencia y de mi trayectoria vital lo que, para el caso que nos ocupa, tampoco es tan importe pues es la opinión de una entre muchas. Por otro, es un tema sumamente complejo y abordarlo con el rigor metodológico suficiente, como para poder extraer conclusiones que tengan algún interés general, es algo que se escapa, desde todo punto de vista, a mis conocimientos y a los datos de los que dispongo. De tal modo que lo que a continuación viene es fruto de una opinión particular aunque, para emitirla, he procurado documentarme previamente. Los datos objetivos, relativos a la situación concreta de las investigadoras del CSIC, los he tomado, entre otras fuentes, del Estudio sobre mujeres investigadoras del CSIC [http://www.csic.es] y, los relativos al área, del último Plan de Actuación del CSIC, 2000-2004. He consultado, así mismo, otras fuentes relativas a la plantilla actual de personal investigador del Organismo.
Linking processes: effects of migratory routes on the distribution of abundance of wintering passerines
Galarza, A.,Tellería, J. L.
Animal Biodiversity and Conservation , 2003,
Abstract: Movements of migratory birds across the Western Paleartic concentrate populations along Atlantic and Mediterranean coasts, thus producing flows of migrants that converge at both extremes of the Pyrenees. Here we analyse the effect of these corridors on the winter distribution of some passerines (F. Motacillidae, F. Turdidae and F. Fringillidae). The number of ring recoveries of migrants at the edges of the Pyrenees was higher than expected, a pattern that was also observed in the case of winter recoveries. In addition, there was a significant decrease in the abundance and species richness of the bird assemblages of the three families analysed wintering in the coastal farmlands of northern Iberian peninsula as their location was further away from the western corridor of the Pyrenees. These results suggest the existence of links between the routes of migratory passerines and their winter densities in northern Iberia.
El polen de las mieles del valle de Río Negro, provincia fitogeográfica del monte (Argentina)
María C. Tellería,Alicia Forcone
Darwiniana , 2000,
Abstract: Tellería, M. C. & Forcone, A. 2000. El polen de las mieles del valle de Río Negro, provinciafitogeográfica del monte (Argentina). Darwiniana 38(3-4): 273-277.Se realizó el análisis palinológico de 41 muestras de miel del valle de Río Negro. El contenido polínicode las muestras fue acetolizado e identificado por comparación con una colección de polen de referencia.Del total de muestras examinadas, 26 fueron mixtas y las restantes monoflorales de: Tamarix gallica (8muestras), Eucalyptus sp. (2 muestras), Melilotus sp. (1 muestra), Centaurea sp. (1 muestra), Prosopissp. (1 muestra), Brassicaceae (1 muestra) y Monttea aphylla (1 muestra). Estas mieles pueden diferenciar-se de aquellas que se producen en el valle inferior del río Chubut, en la misma región fitogeográfica
Caracterización palinológica de las mieles de la llanura del río Senguerr (Chubut-Argentina)
Alicia Forcone,María C. Tellería
Darwiniana , 2000,
Abstract: Forcone, A. & Tellería, M. C. 2000. Caracterización palinológica de las mieles de la llanuradel río Senguerr (Chubut-Argentina). Darwiniana 38(3-4): 267-271.Con el fin de conocer las plantas melíferas de la llanura del río Senguerr, se realizó el análisispalinológico de 19 muestras de miel. El estudio permitió identificar 57 tipos morfológicos y demostrarque las principales fuentes de néctar pertenecen a las familias Fabaceae, Rosaceae, Brassicaceae yAsteraceae. Del total de muestras analizadas 9 resultaron mixtas y 10 monoflorales, de estas últimas, 8fueron de Melilotus sp. y 2 de Rosaceae. Las mieles estudiadas pueden ser caracterizadas por unaasociación polínica de Trifolieae, Brassicaceae, Rosaceae, Acaena sp., Glycyrrhiza astragalina Gillies exHook. & Arn. and Cyperaceae. En la mayoría de las muestras el contenido polínico fue inferior a 2000granos/gramo
Efectos geográficos y ambientales sobre la distribución de las aves forestales ibéricas
Ramírez, á.,Tellería, J. L.
Graellsia , 2003,
Abstract: The peninsular effect is a biogeographical rule according to which species richness decreases as a function from the distance to the mainland base of peninsulas. However, this pattern is frequently obscured by the effect of environmental variables. In this paper we study the relative effect of the geographic location and some environmental variables on the distribution of the richness of Iberian forest birds. Results suggest that both the geographic location and some environmental variables (temperature, precipitation, forest coverage…) affect the species richness. We have also explored if these results can change according to the particular features of the study areas. To approach this, we defined two corridors of a similar length. The Atlantic corridor was quite homogeneous in the study environmental variables while the Mediterranean showed a sharp gradient from moist northern to dry south. Results showed that in the Atlantic corridor, distance to continent and not environmental variables were the main correlates to species richness while in the Mediterranean corridor environmental variables were the best correlates to richness distributions. These results are used to discuss some methodological and biogeographical aspects of the forest bird distribution across the Iberian Peninsula. El efecto península es un patrón según el cual la riqueza de especies disminuye en función de la distancia al continente. Sin embargo, este patrón es frecuentemente enmascarado por la incidencia de variables ambientales. En este trabajo estudiamos el efecto relativo de la ubicación geográfica y de un conjunto de variables ambientales (temperatura, precipitación, cobertura forestal…) sobre la distribución de la riqueza de especies de aves forestales en Espa a peninsular. Los resultados sugieren que tanto la posición geográfica como las condiciones ambientales afectan a la distribución de la riqueza de aves. También se estudia si estos resultados varían en función de las características particulares de las áreas estudiadas. Para esta segunda aproximación se definieron dos corredores de similar longitud ubicados entre las costas atlánticas y mediterráneas y las monta as interiores. El corredor Atlántico mostró una elevada homogeneidad ambiental en toda su extensión, mientras el corredor Mediterráneo presentó un marcado gradiente desde las áreas más húmedas del norte a las condiciones más secas del sur. Los resultados muestran que en el corredor Atlántico la distancia al continente, no las condiciones ambientales, fue la principal predictora de la riqueza de especies, mientra
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