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En los llanos occidentales de Venezuela se presentan planicies aluviales donde la dinámica geomorfológica origina una alta variabilidad textural en los suelos. El objetivo de este trabajo fue conocer la influencia de estas variaciones edáficas sobre la composición florística del sotobosque. Se identificaron sitios de “banco” (arenosos) y de “bajío” (arcillosos) y, en cada uno de ellos, se evaluaron sub-parcelas de sotobosque de 100 m2. El levantamiento incluyó las formas de vida de espermatofitas. Los resultados muestran que algunas especies se pueden considerar “indicadoras” en ciertas condiciones edáficas. En banco son Cyperus sp., Gouania poligama, Hybanthus prunifolius, Xiphidium coeruleum y Zanthoxyllum sp. y en bajío son Asclepias curassavica, Heliconia sp., Inga oerstediana, Luehea seemanii, Piper sp. y Triplaris americana. Los índices de diversidad (riqueza y H´) señalan que no hay diferencias significativas entre banco y bajío, y tampoco entre todos los patios y la vegetación potencial. Ambas condiciones edáficas parecen ofrecer las mismas ventajas para el establecimiento de especies. Por otro lado, en la actual etapa sucesional, se estima que las condiciones microclimáticas en el sotobosque son similares a las existentes en la vegetación potencial. Geomorphological dynamics of the western Venezuelan alluvial plains produce a high textural variability in the soils. The objective of this work was to understand the influence of these edaphic variations on the floristic composition of the understory. “Levee” (sand) and “depression” (clay) sites were identified and, in each one of them, the understory was evaluated on 100 m2 sub-plots. The survey included the spermatophyta life forms. The results show that some species may be considered “indicative” under certain edaphic conditions. In levee are Cyperus sp., Gouania poligama, Hybanthus prunifolius, Xiphidium coeruleum and Zanthoxyllum sp.; in depression are Asclepias curassavica, Heliconia sp., Inga oerstediana, Luehea seemanii, Piper sp. and Triplaris americana. The diversity indexes (richness and H´) point out to neither significant differences between sand and clay soil, nor between all the log landings and the potential vegetation. Both edaphic conditions seem to offer the same advantages for the establishment of species. On the other hand, in the current successional stage, it is considered that the understory microclimatic conditions are similar to the existent ones in the potential vegetation. 36-56 jolozada@ula.ve

The Guayana Shield is one of the oldest territories in the planet and has millions of years subjected to leaching and erosion processes that produce oligotrophic soils. This scarcity of nutrients has not avoided the development of high, diverse and magnificent forests, where plants have adaptations to survive these difficult conditions. The aim of this work was to characterize the physical and chemical parameters of the soils in different forest communities of the Imataca Forest Reserve (IFR), to establish some interpretations on their origin, and some relationships between the edaphic components and the inhabitant species. Terrestrial journeys were carried out and two pathways were traced for the interpretation of forest communities. In each community, three plots (100m x 100m) for the ecological survey were established. In each plot, all trees, palms, and lianas were measured (dbh≥10cm; dbh: diameter at breast height); four 10m x 10m understory sub-plots were evaluated, and a census of all the spermatophyta species (dbh

El aprovechamiento selectivo de maderas es una perturbación que genera una sucesión vegetal. En este proceso algunas especies, adaptadas a la luz, pueden resultar favorecidas y aumentan su importancia. Por su parte, las especies adaptadas a la sombra pueden resultar perjudicadas y disminuyen. El objetivo de este trabajo fue evaluar, mediante parcelas permanentes, los cambios en la composición florística en comunidades forestales con diferentes intensidades de aprovechamiento. Se ejecutó un diseño estadístico de bloques completos al azar, donde se evaluaron los árboles y palmas en parcelas de 1 ha. En estos bosques de bajío, las parcelas testigo están dominadas por Attalea butyracea, Pouteria reticulata, Spondias mombin y Trichantera gigantea. En las parcelas con bajo impacto, no hay cambios significativos en la composición florística. En medio impacto, hay un ligero aumento de pioneras. En alto impacto, las pioneras Cecropia peltata e Inga sp. llegan a tener una importancia conjunta de 20%, a los 11-13 años, pero ya se observa su declive. Selective logging is an interference that generates a forest succession. In this process, some species, adapted to the light, can be favored and they increase their importance. On the other hand, the species adapted to the shade can be injured and they diminish. The objective of this work was to evaluate, by means of permanent plots, the changes in the floristic composition in forest communities with different logging intensities. A statistical design of random complete blocks was executed, where the trees and palms were evaluated in 1 ha plots. In these clay soil forests, the control plots are dominated by Attalea butyracea, Pouteria reticulata, Spondias mombin and Trichantera gigantea. In low impact plots, there are not significant changes in the floristic composition. In medium impact, there is a slight increase of pioneers. On high impact, the pioneers Cecropia peltata and Inga sp. reach a combined importance of 20%, to the 11-13 years, but their decline is already observed. 35-50 jolozada@ula.ve

Los bosques dominados por Mora excelsa forman comunidades casi puras. El objetivo de este trabajo fue caracterizar la estructura, composición florística y suelos, con el fin de evaluar las posibilidades de aprovechamiento sostenible en estos territorios. Se levantaron tres parcelas en bosques primarios y cuatro parcelas en bosques intervenidos. El tamaño de las parcelas fue 100 m x 100 m (individuos con dap = 10 cm, dap: “diámetro a la altura del pecho”). En cada parcela se evaluaron cuatro sub-parcelas de sotobosque de 10 m x 10 m (individuos con dap < 10 cm). Se calculó la densidad, área basal e índice de importancia de cada especie. Los resultados muestran que los bosques de mora (BM) poseen 382 ind/ha, el área basal es de 30 m2/ha. La diversidad es 2 en H´, 11 en a, 40 especies/ha (dap = 10 cm). La especie M. excelsa posee un 34% del índice de importancia y esto es casi nueve veces más alto que la segunda especie más importante (Carapa guianensis). Los BM aprovechados (después de 6-9 años) poseen más de 100 ind/ha (dap = 10 cm) de especies comerciales. Se concluye que en los BM el aprovechamiento puede ser sustentable, porque favorece la recuperación de especies con demanda en el mercado; pero es necesario determinar el turno y el método silvicultural más apropiado para este ecosistema. Forests dominated by Mora excelsa form almost pure communities. The aim of this work was to characterize the structure, floristic composition and edaphic features, with the purpose of evaluating the possibilities for a sustainable logging of these territories. Three plots in primary forests and four plots in logged forests were measured. The plot size was 100 m x 100 m (individuals with dbh = 10 cm, dbh: “diameter at breast height”). In each plot four understory sub-plots of 10 m x 10 m (individuals with dbh

El objetivo de este trabajo es investigar, en la Eurozona, la relación existente entre los mercados de bonos y acciones, conocer y cuantificar dicha relación es de vital importancia en la gestión de riesgos. Con este objetivo se estima la correlación dinámica condicionada, con el modelo DCC-AGARCH (dynamic conditional correlation model with an asymmetric GARCH), entre dos indicadores representativos de dichos mercados: el S&P Eurozone Govermment Bond Index y el Eurostoxx 50. Una vez estimada la correlación dinámica, se analiza cómo el entorno económico condiciona su comportamiento. Para ello se consideran indicadores y variables macroeconómicas y se utiliza el modelo lineal para explicar la relación. Finalmente se estudia la existencia de contagio entre los mercados de bonos y acciones de la Eurozona durante la Crisis Subprime y la Crisis Global Financiera.

La Reserva Forestal Imataca (RFI) es un extenso territorio cubierto, en general, por bosques siempreverdes, con altura superior a 15 m. Como muchas otras zonas del Escudo Guayanés, tiene muy escasos estudios ecológicos e inclusive posee sectores que representan vacíos de información florística. El objetivo de este trabajo fue identificar diferentes comunidades boscosas en la zona central de la RFI, evaluar su estructura y composición florística. Como metodología, se levantaron parcelas de 1 ha y allí se evaluaron los individuos mayores a 10 cm dap; adicionalmente, se realizaron estudios del sotobosque donde se efectuaron censos de los individuos inferiores a 10 cm dap. Con toda esa información se calculó, para cada especie, un Índice de Importancia Ampliado que incluye el IVI y los parámetros del sotobosque. Los resultados indican que todas las parcelas pertenecen a una unidad de vegetación conformada por bosques medios y densos, dominados por los árboles Alexa imperatricis y Pentaclethra macroloba. Otras especies muy importantes son Rinorea riana (arbusto), Bactris maraja (palma pequeña), Ischnosiphon arouma (hierba) y Cheiloclinium hippocrateoides (trepadora). Se concluye que los resultados coinciden con los inventarios realizados por algunas empresas concesionarias, aunque algunos parámetros de diversidad son inferiores a los obtenidos en otros ecosistemas neotropicales. The Imataca Forest Reserve (RFI) is an over 15 m height, broad territory covered, in general, by evergreen forests. Like many other areas of the Guiana Shield, its ecology has been very scarcely studied and inclusive it has sectors that represent lacks of floristic information. The objective of this work was to identify different forest communities in the central area of the RFI, to evaluate its structure and its floristic composition. As a methodology, trees = 10 cm dbh on 1 ha plots were surveyed. Additionally, studies of the understorey were carried out, where censuses were made from the < 10 cm dap individuals. With all that information an Enlarged Index of Importance was calculated, for each species, that includes the IVI and the understorey parameters. The results indicate that all the plots belong to a unit of vegetation conformed by medium and dense forests, dominated by the trees Alexa imperatricis and Pentaclethra macroloba. Other very important species are Rinorea riana (bush), Bactris maraja (small palm), Ischnosiphon arouma (herb) and Cheiloclinium hippocrateoides (climber). We conclude that the results coincide with the inventories carried out by some logging companies, although some diversity parameters are inferior to those obtained in other neotropical ecosystems. 105-131 jolozada@ula.ve remigio@ula.ve semestral

CUORE is a Heart Failure (HF) Disease Assessment System that makes use of innovative approaches, based on Information Technologies (IT) and portable monitoring devices, for the continuous assessment of HF progression and cardiovascular risk stratification. The system valuates the cardiac condition integrating patient data from different sources with special emphasis in the information obtained for ECG processing. Rather than just evaluate the cardiovascular status, the system also aims to motivate patients to have an active role in their health management and to improve their cardiac condition by promotion of an active lifestyle. In order to make the system usable the methodology adopted to create the final solution is iterative and it involves users in all stages. This paper presents the conceptualization of CUORE as a solution to self care for heart failure out of hospital patients.

Poster presentado en The Third International Meeting on Environmental Biotechnology and Engineering celebrado del 21 al 25 de septiembre de 2008, SALTIRSOIL (SALTs in IRrigated SOILs) is a capacity-type, steady-state model developed to predict average major ion content (sodium, calcium, magnesium, chloride, sulfate) in the medium to long term in productive well drained soils. Once the algorithm verification was done the objective of our study was to calibrate SALTIRSOIL under one of several water quality and management scenarios in Mediterranean agriculture. Given that drip and basin are the irrigation methods most representative of irrigated agriculture in Valencia (Spain), this calibration is being performed with climate, soil, irrigation water (composition and management) and crop (species and management) information from an experimental plot drip irrigated with well water and cropped to water melon that has been monitored since late spring 2007. To carry out the calibration, firstly we have performed a sensitivity analysis. That is to change an input variable at a time within a range while maintaining the other variables unchanged and measuring the variability in the model output. Secondly, we have compared simulated saturation soil extract composition against measured data. According to the sensitivity analysis SALTIRSOIL calculations seem to be most affected by climate (rainfall) and water quality and less by soil physical characteristics. According to the first predicted-measured comparisons SALTIRSOIL does not seem to be affected by any systematic error and as a consequence, parameterization would not be needed at least under drip irrigation. On the other hand we have observed that i) the longer the climate data record used for the simulations the closer calculated and measured data are and ii) calculated results are closer to space-averaged measured data than to whichever single point measured data. More comparisons under different water quality and irrigation management practices are needed in order to calibrate SALTIRSOIL in the study area.

Poster presentado en EUROSOIL 2008 celebrado en Viena (Austria) del 25 al 29 de agosto de 2008, The GIS-SALTIRSOIL model is being developed in the framework of a project for soil salinity state and risk appraisal in Mediterranean agricultural areas. SALTIRSOIL calculates the composition of the soil solution, mainly saturation extract, given an irrigation water composition and amount, crop type, climate features and basic physical and chemical soil data. The lower Palancia river basin, in the limit between València and Castelló provinces in Spain, was selected as study area in order to test the model. This agricultural area is interesting because several factors that cause soil salinization, such as high evapotranspiration to rainfall ratios and high salinity irrigation waters, meet. Five experimental plots have been monitored in this area since late spring 2007. The plots were selected in order to test SALTIRSOIL under the four combinations resulting from the following two factors: irrigation water salinity: low or high, and irrigation technique: drip or basin. Soil sampling in different places within the plots, four depths down to 90 cm and throughout the year has been performed, and saturated soil pastes prepared and analysed, in order to have a representative soil salinity dataset from each plot. Irrigation waters have also been sampled and analysed regularly. Furthermore, soil solution ceramic vacuum extractors have been installed at three depths (30, 60 and 90cm) at the water inlet and outlet in basin irrigated plots and close to selected drip emitters in those drip irrigated. Soil solution from these vacuum extractors has been sampled and analysed every time an irrigation or rainfall event has occurred. In addition to this, a broad soil survey has been performed in the whole basin using a salinity sensor based on frequency-domain reflectometry in order to upscale SALTIRSOIL from the plot to the basin scale, that is to test the GISSALTIRSOIL model once is linked.

Màster de Direcció d'Entitats Asseguradores i Financeres, Universitat de Barcelona, Facultat d'Economia i Empresa, Curs: 2003-2004, Tutor: Josep Montañés Navarro, En el presente documento se realiza un análisis de la gestión que se desarrolla actualmente de las pólizas colectivas de vida en el mercado asegurador español, tanto por parte de la entidad aseguradora como de los mediadores. El objeto de dicho análisis es elaborar una propuesta de cambio en dicho proceso de gestión, mediante el uso de tecnologías de información que permitan mejorar la comunicación entre la compañía y el mediador y entre los diferentes departamentos de la compañía, considerando que estamos trabajando con productos que no son estándar y que los procedimientos actuales incorporan una considerable carga administrativa. Con esta propuesta se espera conseguir un aumento de la satisfacción del cliente-mediador y en consecuencia del cliente final (tomador y asegurados).