Biogeographical Analyses and Applications : The Study of Plant Distribution Patterns in West Africa

Studies and applications in biogeography aim at understanding the causes and determinants of past, current, and future diversity distribution patterns. In this context, niche models are currently important tools. They make use of species georeferenced locations and sets of environmental variables to determine the potential suitable habitats of species. The derived results are applied for the conservation of biodiversity but their reliability strongly relies on the quality of the spatial information contained in biological databases. Biodiversity conservation effectiveness strongly depends on the identification of congruent areas for a set of diversity indicators. For example, congruent areas of high species richness for different biological groups. In the first part of this thesis a methodological framework is developed to evaluate the quality of biological databases. As a case example, a database of vascular plants in Benin, Ivory Coast and Burkina Faso is analysed. It consists of a total of 4,587 species collected in 2,931 different localities. Main criteria to evaluate database quality are the spatial configuration of collection localities, their spatial and environmental bias, and their floristic inventory completeness. It was shown that collection localities are unevenly distributed, forming strong clustered patterns and concentrated in the vicinity to cities, the coast, rivers, roads and protected areas. Collection localities represent only a narrow range of the environmental conditions in the study area. A gap selection index was created integrating density of collection localities, environmental bias and inventory completeness to represent those areas in need of more information and to guide future research activities. According to the gap selection index, only the Sahelian zone and surroundings of Comin-Yanga city in Burkina Faso, areas close to the coast and in the border with Liberia in Ivory Coast, and the region of the eastern Guinean forest in Benin are good represented. Different niche models strategies are tested to compare model performance between commonly used approaches, and those that seek to minimize the influence of spatial bias present in the occurrence records. The maximum entropy technique (i.e., Maxent) is used to model species ranges based on biased occurrence records and three types of environmental background information sets. These are random locations (’random background’), the locations of all collection localities except those of the target species (’target background’), and random locations weighed as a function of the gap selection index (’index background’). In average, target background based models perform better than random and index background based models. A visual examination confirms that only target background based models are able to correct for spatial bias. Species richness patterns are estimated to qualitatively describe spatial variations as a result of the three approaches employed Richness patterns strongly vary across the three approaches, but those based on target background models are more accurate to the known positive north-south richness gradient in the study area. In the second part of this thesis, the most comprehensive databases of vascular plants, amphibians and bats in West Africa are used to estimate geographical patterns of species richness and the range size rarity index (as a surrogate of species richness and endemism) at a half degree resolution. The relationship between abiotic factors and these two aspects of diversity are examined through the use of spatial auto-regressive techniques, indicating that elevation heterogeneity and temperature are the main determinants of variation in species richness and range size rarity patterns of the three taxa. Pair-wise correlation comparisons between the three groups for species richness and the range size rarity showed generally high and significant correlations (i.e. > 0.9). However, weak and even negative corelations were found when the comparison was applied at small geographical extents. Hotspots of the range size rarity index for the three groups together occupy 9.3% (i.e. 583.7 km) of the study area. 39.2% of this area is still covered by natural vegetation and 8.5% is covered by protected areas. The main finding of this thesis is that despite the large amount of information available to carry out research in biogeography, analysis and application should not be done without an objective and sound analysis of data quality. Only in this way sources of error and uncertainty can be identified, and proper modeling techniques can be applied. These are crucial steps that need to be followed before drawing conclusions and making decisions for the conservation of biodiversity

Urnula rhytidia (Berk.) Cooke, un raro discomicete (Pezizales, Ascomycotina), hallado en las Villuercas (Cáceres)

Urnula rhytidia, a rare Discomycete (Pezizales, Ascomycotina), collected in Las Villuercas (Caceres, W Spain). A rare ascomycete, Urnula rhy tidia, typically (but not always) associated with Eucalyptus litter, is thoroughly described, illustrated and discussed; its distribution, which is here summarised, is confined to isolated areas in different countries. The latter was reported in Spain once again. The authors afford new information to their previous taxonomic treatments, mainly enlarging the synonimic list. Finally, the curious ornamentation pattern of the spores is showed at S. E. M.Se describe, iconografia y comenta Urnula rhytidia, un raro ascomicete, generalmente (pero no siempre) ligado al humus de Eucalyptus spp ., que sólo aparece en a puntos dispersos en diferentes continentes. Se realiza una síntesis de su distribución, que ahora se amplía por segunda vez en lo que a España se refiere, y de los tratamientos taxonómicos anteriores, con especial énfasis en la lista de sinónimos. Por último, se aporta un estudio detallado al M. E. B. de la curiosa ornamentación esporal

POBREZA Y VULNERABILIDAD EN EL MEDIO RURAL DE CAMPECHE: EL CASO DE LOS JÓVENES QUE NO ESTUDIAN NI TRABAJAN

Con el objetivo de conocer la magnitud del fenómeno nini en el medio rural, se realizó un estudio exploratorio en seis comunidades rurales de alta marginación del estado de Campeche, localizado en el sureste de México. Con base en una metodología que involucra técnicas cuantitativas (encuestas, n=110 hogares, 217 jóvenes) y cualitativas (grupos focales) se describe la situación educativa y laboral de los jóvenes así como sus perspectivas futuras. La proporción de jóvenes nini en las comunidades rurales (45%) es casi dos veces la media nacional (25%). Los jóvenes muestran un perfil de alta motivación por estudiar y superarse, pero el contexto socioeconómico está condenando a una porción significativa a vivir una vida que no desean, generando con ello altos niveles de frustración. Los resultados muestran una ventana de oportunidad para generar políticas públicas que faciliten la integración social y productiva de los jóvenes rurales

Urnula rhytidia (Berk.) Cooke, un raro discomicete (Pezizales, Ascomycotina), hallado en las Villuercas (Cáceres)

Urnula rhytidia, a rare Discomycete (Pezizales, Ascomycotina), collected in Las Villuercas (Caceres, W Spain). A rare ascomycete, Urnula rhy tidia, typically (but not always) associated with Eucalyptus litter, is thoroughly described, illustrated and discussed; its distribution, which is here summarised, is confined to isolated areas in different countries. The latter was reported in Spain once again. The authors afford new information to their previous taxonomic treatments, mainly enlarging the synonimic list. Finally, the curious ornamentation pattern of the spores is showed at S. E. M.Se describe, iconografia y comenta Urnula rhytidia, un raro ascomicete, generalmente (pero no siempre) ligado al humus de Eucalyptus spp ., que sólo aparece en a puntos dispersos en diferentes continentes. Se realiza una síntesis de su distribución, que ahora se amplía por segunda vez en lo que a España se refiere, y de los tratamientos taxonómicos anteriores, con especial énfasis en la lista de sinónimos. Por último, se aporta un estudio detallado al M. E. B. de la curiosa ornamentación esporal

Rheology of cream-like emulsions prepared with soybean milk and low trans vegetable fat

The objective of this work was to study the effect of fat globule size and fat content on the rheological behavior of oil-in-water emulsions prepared with soybean milk, sunflower oil and low trans vegetable fat (LTF). Emulsions were prepared with 40 % w/w lipid phase (containing different proportions of LTF) and three different homogenization methods were used in order to obtain different globule sizes. Emulsions were subjected to controlled magnetic shaking until an increase in thickness. Partial coalescence was observed in all systems containing solid fat, which gave a rheopectic behavior and an increase in the viscoelastic parameters of the emulsions. Smaller particle sizes required higher shaking times to produce an increase in thickness, even though this did not lead to different final values of the viscoelastic parameters. The highest partial coalescence degree was observed at 50 % LTF in lipid phase, but the highest final viscoelastic parameters after shaking were observed at 100 % LTF in the lipid phase. The rheological behavior of these emulsions indicates that they could be a potential vegetable substitute for traditional dairy creams.Fil: Márquez, Andrés Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; ArgentinaFil: Wagner, Jorge Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentin

Writing a Case Report: A Work of Art

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Rheology of double (w/o/w) emulsions prepared with soybean milk and fortified with calcium

The objective of this work was to study the rheological behavior of water-in-oil-in-water (w/o/w) emulsions prepared with soybean milk and sunflower oil, with different calcium solutions as the internal aqueous phase, in order to evaluate them as a vegetable substitute of whipped dairy cream. The obtained systems exhibited a creamy texture, which was attributed to the swelling of w/o droplets because of the osmotic gradient generated by the inclusion of soluble salts in the internal aqueous phase. A secondary factor could be the flocculation of w/o droplets due to the interaction of released calcium with soybean proteins at the interface. Consequently, the increase of calcium chloride content produced emulsions with higher consistency. A pasteurization produced flocculation and coalescence of w/o droplets only at high calcium chloride content. These double emulsions could be a potential alternative to the whipped dairy cream, because of their texture, reduced fat content and calcium contribution.Fil: Márquez, Andrés Leonardo. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; ArgentinaFil: Wagner, Jorge Ricardo. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Exercise addiction: an emergent behavioral disorder

relevante en el mantenimiento de la salud y en la prevención de la enfermedad. Sin embargo, el ejercicio en exceso puede generar efectos adversos tanto sobre la salud física como mental. Objetivos: sintetizar el estado actual de los conocimientos sobre la adicción al ejercicio, considerando su definición, síntomatología, diagnóstico, aspectos epidemiológicos, factores etiológicos y posibilidades de intervención. Método: se revisaron artículos relacionados con el tema en las bases de datos Pubmed, Sportdiscus, PsycINFO, Scopus y Web of Science, utilizando combinaciones de las siguientes palabras clave: “ejercicio”, “adicción” y “dependencia”. Resultados: el ejercicio regular practicado en exceso puede generar comportamientos adictivos con consecuencias adversas sobre la salud y pérdida de la calidad de vida. El diagnóstico de la adicción al ejercicio se apoya en la utilización de cuestionarios, siendo los más empleados la Escala de Dependencia del Ejercicio (EDS) y el Inventario de Adicción al Ejercicio (EAI). Mediante dichos instrumentos se ha estimado una prevalencia entre quienes practican habitualmente ejercicio en torno a un 3%. Las distintas hipótesis propuestas para explicar la etiología de este trastorno incluyen mecanismos tanto fisiológicos como psicológicos. El tratamiento se basa en aproximaciones cognitivo-conductuales, cuya eficacia requiere confirmación. Conclusiones: aunque existen distintas hipótesis para explicar la dependencia del ejercicio, aún son necesarios modelos integrativos. También se requiere una validación clínica de los instrumentos utilizados para el diagnóstico y la profundización en la relación con las alteraciones de la conducta alimentaria.Background: regular physical activity plays a relevant role in health maintenance and disease prevention. However, excess exercise may generate adverse effects both on physical and mental activity. Aims: to provide a state-of-the-art overview on exercise addiction, considering its concept, symptoms, diagnosis, epidemiological aspects, etiological factors, and potential interventions. Methods: articles related to the topic were reviewed through Pubmed, Sportdiscus, PsycINFO, Scopus and Web of Science databases, using combinations of the following keywords: “exercise”, “addiction” and “dependence”. Results: regular exercise taken into excess may result in adverse health consequences and quality of life impairment. Diagnosis of exercise addiction requires the employment of questionnaires such as the Exercise Dependence Scale (EDS) and the Exercise Addiction Inventory (EAI). These instruments have allowed the estimation of a 3% prevalence among exercise practitioners. Proposed hypotheses to explain the etiology of this disorder include both physiological and psychological mechanisms. Treatment is based on the cognitive-behavioral approach, but effectiveness needs to be evaluated. Conclusions: although different hypotheses have been proposed to explain exercise dependence, integrative models are still necessary. A clinical validation of diagnostic instruments and a deepening into the relationship with behavioral eating disorders are also required

La burocracia a discusión: del tamaño y la eficiencia a la democracia

Este ensayo parte de la premisa de que es necesario replantear la cuestión de la burocracia estatal, situando el debate en un contexto problemático más amplio. En su análisis se han privilegiado la redimensionalización del aparato estatal y la modernización de la administración pública. Sin dejar de lado estos temas, el autor propone replantear la cuestión en términos de las relaciones entre burocracia y democracia, en el marco del proceso de reforma del Estado

Epistemología y normativa crítica

A partir de diversos trabajos realizados por teóricos mexicanos, en particular Hugo Zemelman y Enrique de la Garza, en tomo a la producción e indagación epistemológica local y sus factores determinantes, el autor profundiza en el estado que guardan actualmente. Posteriormente, analiza los contenidos sustanciales de la propuesta epistemológica de Zemelman, que parte del concepto de totalidad, y propone elementos alternativos para el eventual desarrollo de la misma