Capacidad predictiva de las relaciones estadísticas entre los volúmenes de precipitación de las cuencas de la Península Ibérica y las temperaturas de la superficie de los océanos Atlántico y Pacífico del periodo 1946-1994

Ponencia presentada en: V Simposio Nacional de Predicción, celebrado en 2001 en Madrid.El objetivo del trabajo es buscar relaciones entre anomalías atmosféricas y anomalías de las temperaturas superficiales del agua del mar (SST) con distintas estaciones de retardo. Para ello se utiliza el Análisis de Correlación Canónica (ACC) entre las anomalías de SST del Atlántico y del Pacífico y las anomalías de los volúmenes de precipitación de cada una de las cuencas de la Península Ibérica en el periodo 1946-1994. Las correlaciones significativas son utilizadas para predecir. La medida de la bondad de las predicciones, se obtiene calculando las curvas ROC y el valor económico para los terciles seco, normal y húmedo. Los resultados obtenidos indican que, existe una capacidad predictiva, respecto a las SST del Atlántico para la misma estación, en la cuencas de la vertiente atlántica en invierno y en el Segura en primavera. Con respecto a las SST del Pacífico, se muestra capacidad predictiva para la cuenca Sur con dos estaciones de retardo a principios de la primavera y simultanea para el Levante a finales del verano

Características del poder y la rentabilidad en las empresas familiares jiennenses: teoría de agencia versus dirección estratégica

El objetivo de este trabajo es el análisis, bajo los argumentos de la Teoría de Agencia y la Dirección Estratégica, del tipo de estructura de poder que es más ventajoso para la empresa familiar andaluza; esto es, aquella independiente que permite controlar y vigilar el comportamiento oportunista desarrollado por los directivos, o por el contrario, la de naturaleza dual que otorga discreción y poder al propietario de la empresa familiar. Para ello, tras revisar la literatura correspondiente, se plantean tres hipótesis cuyo contraste se efectúa sobre una muestra de 856 empresas familiares jiennenses.The main purpose of this paper is to analyze, under the arguments of Agency Theory and Strategic Management, what type of power structure is more advantageous for the family business and its proprietors, one independent that allows to control the manager´s opportunist behavior, or other dual that grants discretion and power to the president of the family business. For it, after revising the corresponding literature, three hypotheses are formulated and tested on a sample of 856 family business

Statistical and dynamical downscaling of precipitation over Spain from DEMETER seasonal forecasts

Statistical and dynamical downscaling methods are tested and compared for downscaling seasonal precipitation forecasts over Spain from two DEMETER models: the European Centre for Medium-Range Weather Forecasts (ECMWF) and the UK Meteorological Office (UKMO). The statistical method considered is a particular implementation of the standard analogue technique, based on close neighbours of the predicted atmospheric geopotential and humidity fields. Dynamical downscaling is performed using the Rossby Centre Climate Atmospheric model, which has been nested to the ECMWF model output, and run in climate mode for six months. We first check the performance of the direct output models in the period 1986–1997 and compare it with the results obtained applying the analogue method. We have found that the direct outputs underestimate the precipitation amount and that the statistical downscaling method improves the results as the skill of the direct forecast increases. The highest skills – relative operating characteristic skill areas (RSAs) above 0.6 – are associated with early and late spring, summer and autumn seasons at zero- and one-month lead times. On the other hand, models have poor skill during winter with the exception of the El Niño period (1986–1988), especially in the south of Spain. In this case, high RSAs and economic values have been found. We also compare statistical and dynamical downscaling during four seasons, obtaining no concluding result. Both methods outperform direct output from DEMETER models, but depending on the season and on the region of Spain one method is better than the other. Moreover, we have seen that dynamical and statistical methods can be used in combination, yielding the best skill scores in some cases of the study

Sistema de vigilància de vacunes de Barcelona, VigiVacBcn

Promoció de la salu

The Origin of The Acheulean: The 1.7 Million-Year-Old Site of FLK West, Olduvai Gorge (Tanzania)

The appearance of the acheulean is one of the hallmarks of human evolution. It represents the emergence of a complex behavior, expressed in the recurrent manufacture of large-sized tools, with standardized forms, implying more advance forethought and planning by hominins than those required by the precedent Oldowan technology. The earliest known evidence of this technology dates back to c. 1.7 Ma. and is limited to two sites (Kokiselei [Kenya] and Konso [Ethiopia]), both of which lack functionally-associated fauna. The functionality of these earliest Acheulean assemblages remains unknown. Here we present the discovery of another early Acheulean site also dating to c. 1.7 Ma from Olduvai Gorge. This site provides evidence of the earliest steps in developing the Acheulean technology and is the oldest acheulean site in which stone tools occur spatially and functionally associated with the exploitation of fauna. Simple and elaborate large-cutting tools (LCT) and bifacial handaxes co-exist at FLK West, showing that complex cognition was present from the earliest stages of the acheulean. Here we provide a detailed technological study and evidence of the use of these tools on the butchery and consumption of fauna, probably by early Homo erectus sensu lato