472 research outputs found

    Primera demostración paleontológica del Kimmeridgiense en el Garraf (Barcelona)

    Get PDF
    El hallazgo de Pagiophyllum cirinicum (SAPORTA), (Cofiferales), en la parte inferior de las dolomias de Garraf confirma la cronostratigrafia  kimmeridgiense de la mayor parte de tales dolomias Se ofrece además una visión estratigráfica de todo el conjunto

    Una visión de la obra y el herbario de Rouy a través del género Carex L.

    Get PDF
    Se analiza la obra de Georges Rouy, célebre botánico francés, mediante el estudio de sus materiales así como del tratamiento del género Carex (Cyperaceae) en la Flore de France. Se valora favorablemente el conocimiento que el autor demuestra sobre este género, puesto de manifi esto al incluir subgéneros en la clasifi cación taxonómica. Asimismo la sinonimia que propone para cada nombre y las descripciones de los taxones son muy completas. Al contrario, se valora negativamente la excesiva fragmentación que estableció, pues incluyó demasiadas secciones y subsecciones. Finalmente, su rechazo a utilizar las normas nomenclaturales establecidas por el Código de Nomenclatura Botánica conduce a la confusión e impide que la mayoría de sus nombres sean válidos.The George Rouy’s work, a famous French botanist, is studied by means of his material and literature of the genus Carex (Cyperaceae). We assess positively the knowledge that he demonstrated of this genus; because of the subgenera differentiated in his treatment, besides the complete synonymy presented for each name and the taxa descriptions. But he splitted excessively the infrageneric classifi cation including too many sections and subsections. Finally, most of the names he proposed are invalid because of his rejection of the International Code of Botanical Nomenclature recommendations and rules

    Bitter taste receptor polymorphisms and human aging.

    Get PDF
    Several studies have shown that genetic factors account for 25% of the variation in human life span. On the basis of published molecular, genetic and epidemiological data, we hypothesized that genetic polymorphisms of taste receptors, which modulate food preferences but are also expressed in a number of organs and regulate food absorption processing and metabolism, could modulate the aging process. Using a tagging approach, we investigated the possible associations between longevity and the common genetic variation at the three bitter taste receptor gene clusters on chromosomes 5, 7 and 12 in a population of 941 individuals ranging in age from 20 to 106 years from the South of Italy. We found that one polymorphism, rs978739, situated 212 bp upstream of the TAS2R16 gene, shows a statistically significant association (p = 0.001) with longevity. In particular, the frequency of A/A homozygotes increases gradually from 35% in subjects aged 20 to 70 up to 55% in centenarians. These data provide suggestive evidence on the possible correlation between human longevity and taste genetics
    • …
    corecore