86 research outputs found

    Reduced reproductive fitness of an endemic insular juniper population: an eco-genetic mediation hypothesis

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    The mutual reinforcement of multiple drivers of global change erodes ecosystem services and accelerates plant population decline worldwide. This is particularly the case for island ecosystems where anthropogenic activity has imperilled insular floras for centuries. Different hypotheses have put forward the combined effects of environmental shifts and genetic factors in driving fecundity decline in threatened populations. In this study, we combined population genetics tools and structural equation models to test the eco-genetic mediation hypothesis, that the environmental conditions influence genetic variation, which in turn affects plant fitness. Our study species is Juniperus cedrus, an endangered juniper species endemic to the Canary Islands. Juniper woodlands have been depleted since the arrival of human inhabitants confined extant populations to marginal lands. More recently, long-distance dispersers have been extirpated from the study area, potentially eliminating connectivity among fragmented populations. We expected strong intrapopulation subdivision and high levels of inbreeding and kinship that should negatively affect individual fitness. We found evidence of population subdivision into several mating neighbourhoods (K=13), some of them highly inbred. However, contrary to our expectations, neither inbreeding nor mean kinship mediated a population response to environmental factors. Our results suggest three remedial actions to reverse the declining demographic trends: (i) re-establish native vegetation to ameliorate local environmental conditions; (ii) restore dispersal services to increase connectivity; and (iii) monitor fitness decline to identify lagged effects associated with deforestation. Overall, this study shows that structural equation models combined with population genetics techniques are suitable tools to identify high-order effects among multiple drivers of global change that underlie forest decline

    caracterizacion etologica de la raza camellar canaria

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    El interés creciente en la aplicación de las ciencias del comportamiento a la producción animal ha posibilitado el desarrollo progresivo de técnicas para el mejoramiento y ajuste de los sistemas de manejo con vistas a obtener rendimientos productivos elevados en el marco de la sostenibilidad. La reproducción selectiva y diferencial para rasgos conductuales específicos y deseables en la raza camellar canaria (Camelus dromedarius), previa caracterización etofuncional, puede aplicarse a lograr un incremento del valor adaptativo de los animales a las presiones de los sistemas de producción pecuaria en que se encuentran. Esta iniciativa se enmarca en un plan estratégico de conservación, mejora y fomento de una raza autóctona amenazada a través de vías alternativas de rentabilidad y utilización sostenibles de la raza y sus productos. La cualificación del equipo humano implicado, así como la optimización técnica y mecánica de las infraestructuras en los sistemas de producción camellar, se convierten en objetivos de consideración prioritaria en etología aplicada

    caracterizacion zoometrica y evaluacion de la condicion corporal en la raza camellar canaria

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    La conservación, mejora y uso racional de los recursos genéticos animales locales y su diversidad son propósitos prioritarios a nivel nacional e internacional de evidente carácter legítimo. Reconocida en situación de amenaza, la raza camellar canaria (Camelus dromedarius) se encuentra marginalmente reducida a las islas orientales del archipiélago. Su uso queda restringido fundamentalmente a la explotación turística y, de forma esporádica, a labores variadas en el ámbito agropecuario. La caracterización morfoestructural y zoométrica del camello canario es una tarea clave que permitirá la identificación de aquellos caracteres o rasgos fenotípicos implicados en la actividad productivo-económica de estos animales con el fin de recuperar posibles nuevos nichos funcionales. La presente propuesta metodológica se enmarca en un contexto de oportunidad y resurgimiento de una potencial industria de producción con el asentamiento de las bases para un programa de recuperación y cría selectiva de esta raza camellar a través de su sustentabilidad funcional

    Revista del Consejo Superior de Investigaciones Científicas

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    Alimentación del meloncillo Herpestes ichneumon y de la gineta Genetta genetta en la Reserva Biológica de Doñana, S.O. de la Península Ibérica.Determinación de la edad en Rana perezi Seoane, 1885. Aplicación al análisis del crecimiento somático de poblaciones.Influencias ambientales en la variación del tamaño, forma y peso de los huevos de la collalba rubia (Oenanthe hispanica L.)Características de un coro de sapos corredores (Bufo calamita) en el sureste de España.Estrategias alimentarias del ciervo (Cervus elaphus L.) en Montes de ToledoDistribución de los quirópteros de la provincia de Orense (Noroeste de España).Ecología trófica del lince ibérico en Doñana durante un periodo secoDesarrollo larvario de la rana común (Rana perezi) (anura: ranidae) en charcas temporales del noroeste de la Península Ibérica.Régimen alimenticio del mirlo común (Turdus merula) en el sureste de la Península Ibérica durante el periodo otoño-invierno.Reproducción del gorrión molinero (Passer montanus) en las Islas Canarias.Relación entre la cobertura vegetal y la distribución de nidos en las colonias de pagaza piconegraPeer reviewe

    In-doped gallium oxide micro- and nanostructures: morphology, structure, and luminescence properties

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    The influence of indium doping on morphology, structural, and luminescence properties of gallium oxide micro- and nanostructures is reported. Indium-doped gallium oxide micro- and nanostructures have been grown by thermal oxidation of metallic gallium in the presence of indium oxide. The dominant morphologies are beltlike structures, which in many cases are twisted leading to springlike structures, showing that In diffusion in Ga2O3 influences the microstructure shapes. High-resolution transmission electron microscopy has revealed the presence of twins in the belts, and energy-dispersive X-ray spectroscopy in the scanning electron microscopy (SEM) has detected a segregation of indium impurities at the edges of planar structures. These results suggest that indium plays a major role in the observed morphologies and support the assumption of a layer by layer model as growth mechanism. An additional assessment of indium influence on the defect structure has been performed by cathodoluminescence in the SEM, X-ray photoelectron microscopy, and spatially resolved Raman spectroscopy

    Regulation of cell death receptor S-nitrosylation and apoptotic signaling by Sorafenib in hepatoblastoma cells

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    Nitric oxide (NO) plays a relevant role during cell death regulation in tumor cells. The overexpression of nitric oxide synthase type III (NOS-3) induces oxidative and nitrosative stress, p53 and cell death receptor expression and apoptosis in hepatoblastoma cells. S-nitrosylation of cell death receptor modulates apoptosis. Sorafenib is the unique recommended molecular-targeted drug for the treatment of patients with advanced hepatocellular carcinoma. The present study was addressed to elucidate the potential role of NO during Sorafenib-induced cell death in HepG2 cells. We determined the intra- and extracellular NO concentration, cell death receptor expression and their S-nitrosylation modifications, and apoptotic signaling in Sorafenib-treated HepG2 cells. The effect of NO donors on above parameters has also been determined. Sorafenib induced apoptosis in HepG2 cells. However, low concentration of the drug (10nM) increased cell death receptor expression, as well as caspase-8 and -9 activation, but without activation of downstream apoptotic markers. In contrast, Sorafenib (10 µM) reduced upstream apoptotic parameters but increased caspase-3 activation and DNA fragmentation in HepG2 cells. The shift of cell death signaling pathway was associated with a reduction of S-nitrosylation of cell death receptors in Sorafenib-treated cells. The administration of NO donors increased S-nitrosylation of cell death receptors and overall induction of cell death markers in control and Sorafenib-treated cells. In conclusion, Sorafenib induced alteration of cell death receptor S-nitrosylation status which may have a relevant repercussion on cell death signaling in hepatoblastoma cells.Instituto de Salud Carlos III PI13/00021Ministerio de Economía y Competitividad BFU2012-32056Consejería de Economía, Innovación, Ciencia y Empleo, Junta de Andalucía BIO-0216Consejería de Economía, Innovación, Ciencia y Empleo, Junta de Andalucía CTS-6264Consejería de Salud, Junta de Andalucía PI13/ 0002

    Modifiable risk factors associated with prediabetes in men and women: A cross-sectional analysis of the cohort study in primary health care on the evolution of patients with prediabetes

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    Background: Prediabetes is a high-risk state for diabetes development, but little is known about the factors associated with this state. The aim of the study was to identify modifiable risk factors associated with the presence of prediabetes in men and women. Methods: Cohort Study in Primary Health Care on the Evolution of Patients with Prediabetes (PREDAPS-Study) is a prospective study on a cohort of 1184 subjects with prediabetes and another cohort of 838 subjects without glucose metabolism disorders. It is being conducted by 125 general practitioners in Spain. Data for this analysis were collected during the baseline stage in 2012. The modifiable risk factors included were: smoking habit, alcohol consumption, low physical activity, inadequate diet, hypertension, dyslipidemia, and obesity. To assess independent association between each factor and prediabetes, odds ratios (ORs) were estimated using logistic regression models. Results: Abdominal obesity, low plasma levels of high-density lipoprotein cholesterol (HDL-cholesterol), and hypertension were independently associated with the presence of prediabetes in both men and women. After adjusting for all factors, the respective ORs (95% Confidence Intervals) were 1.98 (1.41-2.79), 1.88 (1.23-2.88) and 1.86 (1.39-2.51) for men, and 1.89 (1.36-2.62), 1.58 (1.12-2.23) and 1.44 (1.07-1.92) for women. Also, general obesity was a risk factor in both sexes but did not reach statistical significance among men, after adjusting for all factors. Risky alcohol consumption was a risk factor for prediabetes in men, OR 1.49 (1.00-2.24). Conclusions: Obesity, low HDL-cholesterol levels, and hypertension were modifiable risk factors independently related to the presence of prediabetes in both sexes. The magnitudes of the associations were stronger for men than women. Abdominal obesity in both men and women displayed the strongest association with prediabetes. The findings suggest that there are some differences between men and women, which should be taken into account when implementing specific recommendations to prevent or delay the onset of diabetes in adult population
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