19 research outputs found

    Estudio preliminar de la estructura interna del subtipo fitoclimático VI (IV)1 de Allué (1990). Aplicaciones fitoclimáticas

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    In this paper we try to establish a preliminary methodology for analyzing vegetation structures included in Allué´s (1990) phytoclimatic subtypes, and their phytoclimatic implications. One of the most geographically extensive subtypes (VI(IV)1) has been chosen, which comprises a considerable number of syntaxa.En este trabajo se pretende establecer una metodología preliminar para analizar en profundidad las estructuras de vegetación que están presentes en los subtipos fitoclimáticos de Allué (1990), así como sus implicaciones fitoclimáticas. Se ha elegido para este estudio uno de los subtipos más extensos territorialmente (VI(IV)1), en el que están representados un número considerable de sintáxones

    Can environmental constraints determine random patterns of plant species co-occurrence?

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    Plant community ecologists use the null model approach to infer assembly processes from observed patterns of species co-occurrence. In about a third of published studies, the null hypothesis of random assembly cannot be rejected. When this occurs, plant ecologists interpret that the observed random pattern is not environmentally constrained – but probably generated by stochastic processes. The null model approach (using the C-score and the discrepancy index) was used to test for random assembly under two simulation algorithms. Logistic regression, distance-based redundancy analysis, and constrained ordination were used to test for environmental determinism (species segregation along environmental gradients or turnover and species aggregation). This article introduces an environmentally determined community of alpine hydrophytes that presents itself as randomly assembled. The pathway through which the random pattern arises in this community is suggested to be as follows: Two simultaneous environmental processes, one leading to species aggregation and the other leading to species segregation, concurrently generate the observed pattern, which results to be neither aggregated nor segregated – but random. A simulation study supports this suggestion. Although apparently simple, the null model approach seems to assume that a single ecological factor prevails or that if several factors decisively influence the community, then they all exert their influence in the same direction, generating either aggregation or segregation. As these assumptions are unlikely to hold in most cases and assembly processes cannot be inferred from random patterns, we would like to propose plant ecologists to investigate specifically the ecological processes responsible for observed random patterns, instead of trying to infer processes from patternsThis research and publication was possible thanks to a postdoctoral fellowship at The Open University (UK) and the project “Development of the recovery plan for A. rioxana in la Rioja. Measures of research, monitoring and control (University of Salamanca)”, both funded by the Regional Government of La Rioja (Spain

    The adolescent onset anorexia nervosa study (ANABEL): Design and baseline results

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    The anorexia nervosa adolescent longitudinal biomarker assessment study (ANABEL) is a 2‐year longitudinal study. [Objective]: Evaluate several clinical, biochemical, immunological, psychological, and family variables and their interactions in adolescent onset eating disorders (EDs) patients and their 2‐year clinical and biological outcome. This article illustrates the framework and the methodology behind the research questions, as well as describing general features of the sample. [Methods]: A longitudinal study of 114 adolescents with EDs seeking treatment was performed. Only adolescents were selected during 4 years (2009–2013). The variables were collected at different times: baseline, 6, 12, 18, and 24 months of the start of treatment. Diagnoses were completed through the semi‐structured Kiddie‐Schedule for Affective Disorders and Schizophrenia interview. [Results]: At baseline, the mean age was 15.11 (SD = 1.36). The mean ED duration was 10 months (SD = 5.75). The mean body mass index was 16.1 (SD = 1.8). The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition diagnosis at baseline for restrictive anorexia nervosa was 69.6%, 17.4% for purgative anorexia nervosa, and 24.3% for other specified feeding disorder. At 12 months, 19.4% were in partial remission, whereas at 24 months, 13.8% had fully recovered and 29.2% had partially recovered. [Conclusions]: There was an acceptable physical and psychopathological improvement during the first year of treatment, with recovery being more evident during the first 6 months.This project received grants from the Instituto de Salud Carlos III. Fondo Investigación (FIS PI08/1832) and Alicia Koplowitz Foundation (2009).Peer reviewe
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